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Wyszukujesz frazę "calcite" wg kryterium: Temat


Wyświetlanie 1-62 z 62
Tytuł:
Dolomite and calcite enhancement of whey protein isolate hydrogels
Autorzy:
Norris, K.
Tsang, S. C.
Kerns, J. G.
Kłosek-Wawrzyn, E.
Jaegermann, Z.
Douglas, T. E. L.
Powiązania:
https://bibliotekanauki.pl/articles/285345.pdf
Data publikacji:
2018
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Polskie Towarzystwo Biominerałów
Tematy:
hydrogels
dolomite
calcite
Źródło:
Engineering of Biomaterials; 2018, 21, 148; 98
1429-7248
Pojawia się w:
Engineering of Biomaterials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Changes of surface properties of calcite particles with calcium stearate using conventional experimental design and properties of coated calcite
Autorzy:
Ucurum, M.
Bayram, O.
Toraman, O. Y,
Kılıc, H.
Yalcın, S.
Powiązania:
https://bibliotekanauki.pl/articles/109347.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
calcite
surface modification
mechano-chemical
calcium stearate
properties of modified calcite
Opis:
Calcite is utilized as a filler mineral in the industries such as plastics, rubber, and paint, to gain products with a variety of features. In order to use a calcite ore as a filler, some specific physical and physico-chemical properties are required such as ultra-fine sizes and conversion of hydrophilic to hydrophobic structure. In the present study, for these purposes, surfaces of the ultra-fine calcite powder (d50=2.94 μm) were coated by a mechano-chemical process with calcium stearate [Ca(C17H35COO)2] in a stirred ball mill. The influence of operating parameters such as calcite filling-ratio, ball-filling ratio, operation speed, grinding time and chemical dosage on the active ratio (%) was systematically examined. Then, the properties of modified calcite product were measured and evaluated by contact angle, TGA, DTA, FTIR, and SEM. The results showed that the mechano-chemical technology is very effective for modifying the surface of micronized calcite products using calcium stearate chemical.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 3; 688-700
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Separation of magnesite and calcite based on flotation solution chemistry
Autorzy:
Yao, Jin
Gong, Xiufeng
Sun, Haoran
He, Ruofan
Yin, Wanzhong
Powiązania:
https://bibliotekanauki.pl/articles/2146910.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
magnesite
calcite
reverse flotation
Opis:
The dissolution characteristics of minerals, dissolution of flotation agents in solutions, and equilibrium of dissociations and associations serve as the basis for determining the optimal conditions for the effective components of flotation agents and for evaluating the interaction between flotation agents and minerals. This basis provided the theoretical support for the flotation separation of minerals. Based on this, the flotation separation of magnesite and calcite was realized using sodium dihydrogen phosphate, also known as monosodium phosphate (MSP), as a regulator and dodecylamine (DDA) as a collector. When MSP was used in the DDA system, single-mineral and binary mixed-ore flotation tests revealed that the floatability of calcite was significantly greater than that of magnesite and the separation of magnesite and calcite was more effective, respectively. Zeta potential measurements showed that MSP-containing negative groups could selectively reduce the zeta potential of calcite and promote the adsorption of DDA-containing positive groups on the surface of the calcite. However, this effect was negligible on the zeta potential of magnesite. Due to the stronger affinity of MSP to Ca2+ than that to Mg2+, as demonstrated by Fourier transform infrared and X-ray photoelectron spectroscopy analyses, the MSP was adsorbed onto the surface of calcite primarily by hydrogen bonds rather than magnesite, which promoted the stronger adsorption of DDA-containing positive groups on the surface of the calcite. As a result, the differences in the floatability of magnesite and calcite were enlarged by MSP. Thus, MSP can be utilized an effective regulator for the efficient separation of magnesite from calcite via reverse flotation.
Źródło:
Physicochemical Problems of Mineral Processing; 2022, 58, 4; art. no. 149398
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Żyłowe złoża kalcytów
Vein calcite deposits
Autorzy:
Bąk, B.
Kuć, P.
Nieć, M.
Powiązania:
https://bibliotekanauki.pl/articles/170852.pdf
Data publikacji:
2016
Wydawca:
Poltegor-Instytut Instytut Górnictwa Odkrywkowego
Tematy:
kalcyt
żyły kalcytowe
różanka
wapienie
dolomity
calcite
vein of calcite
limestone
dolomite
Opis:
Żyły kalcytów cechujące się znaczną grubością, od kilku do kilkunastu, rzadziej kilkudziesięciu metrów, występują w obszarze kielecko-chęcińskim oraz w rejonie Krzeszowic koło Krakowa. Niektóre z nich są udokumentowane i wykazywane w krajowym bilansie zasobów. Obecnie nie mają znaczenia gospodarczego i nie są eksploatowane. Miały one znaczenie w przeszłości. Wydobywano z nich kalcyt żyłowy, zwany „różanką”, ceniony z uwagi na jego walory dekoracyjne. Wykorzystywane były głównie w budownictwie sakralnym. Żyły kalcytu występujące w strefie zaburzeń tektonicznych, przez co cechuje je złożona budowa o zróżnicowanych teksturach. Poszczególne generacje kalcytu różnią się barwą i strukturą skupień kalcytu. Kalcyt zazwyczaj jest grubokrystaliczny, często jego agregaty mają budowę pręcikową. Żyły mają budowę złożoną, krystyfikacyjną i brekcjową. W drugiej połowie XX w. żyły kalcytowe, z przyczyn ekonomicznych i względów ochrony środowiska, straciły znaczenie gospodarcze. Ich eksploatacja na niewielką, rzemieślniczą skalę, powinna być nadal możliwa jako źródło kamienia do rekonstrukcji starych zabytków architektonicznych.
Pure calcite veins of considerable thickness up to teens of meters, that occurs in the western part of Holy Cross Mts., and to the West of Kraków, were economically important in the past. Their coarse crystalline varied: banded, cockade or breccia structure and varied rose coloration, make theme unique decorative, ornamental stone. Recently, they lost importance due to small size and environment protection exigencies, however they are listed in governmental mineral resources inventory. Their small scale, artisanal quarrying is still possible, as a source of ornamental stone for reconstruction of old architectural monuments.
Źródło:
Górnictwo Odkrywkowe; 2016, 57, 5; 34-41
0043-2075
Pojawia się w:
Górnictwo Odkrywkowe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Applicability of statistical process control for surface modification plant and properties of coated calcite
Autorzy:
Ucurum, M.
Malgir, E.
Deligezen, H.
Karaer, N.
Avsar, M.
Powiązania:
https://bibliotekanauki.pl/articles/110501.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
calcite
surface modification
pin mill plant
statistical process control
coated calcite properties
Opis:
Due to its low surface energy, easy dispersion, high homogeneity and whiteness, coated (modified) calcite has increasingly been used in many industries, particularly in the plastics. The demand for this product will most likely increase in the years to come. Surface modification of calcite with a fatty acid would lead to a great expansion of industrial applications. The color values of coated calcite products are the first quality parameter. Therefore, it is very important to monitor the variations in the color characteristics of the coated calcite products. It is well known that statistical process control (SPC) techniques have been widely used in the many industries. In the present study, the surface of micronized calcite was coated with stearic acid by a pin mill. X-R control graphics and process capability index were applied for monitoring variations in quality control based on color parameters (L*, a* and b*) for the pin mill plant. In addition, active ratio, particle size distribution, whiteness parameters, BET, FTIR, TGA-DTA and SEM were then determined on a coated calcite sample. The results show that the pin mill plant seems under control and the coating technology is very effective in modifying the surface of micronized calcite products.
Źródło:
Physicochemical Problems of Mineral Processing; 2016, 52, 2; 803-820
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Evaluation Potential as Micronized Calcite of White Marble Waste
Ocena potencjału pozyskania zmikronizowanego kalcytu z odpadów z białego marmuru
Autorzy:
Deniz, Vedat
Polat, Ercan
Powiązania:
https://bibliotekanauki.pl/articles/318935.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Przeróbki Kopalin
Tematy:
calcite
marble wastes
micronized calcite
physical properties of micronized calcite
chemical properties of micronized calcite
physicochemical properties of micronized calcite
mineralogical properties of micronized calcite
kalcyt
odpady marmuru
kalcyt mikronizowany
właściwości fizyczne mikronizowanego kalcytu
właściwości chemiczne mikronizowanego kalcytu
właściwości fizykochemiczne mikronizowanego kalcytu
właściwości mineralogiczne mikronizowanego kalcytu
Opis:
Natural calcium carbonates have a great importance in the world’s economy due to their numerous applications areas such as calcium carbonate in the paper and paint industries. The final calcite products have rigorous quality specifications which are currently difficult to meet for local producers in Turkey. Therefore, large quantities of high white marble wastes have been transported long distances inside the country to supply the different industrial plants for using calcite. Marble wastes, located in Afyon and Kutahya regions, Turkey’s mid-west, are used generally for concrete and highway purposes. Evaluations of marble wastes are very important for the economic development of any country or region. This study aims at developing new perspective for evaluation of marble wastes as domestic calcite resources and serves as a guide for investment and decision making for the Turkey calcite industry. This paper presents applied research work to determining the product quality for evaluation as micronized calcite of marble wastes and gives an overview of the market situation for the regional producers. The aim of the work is to characterize four different marble wastes and to determine the potential for production of the required quality for the Turkey calcite market;- to control the quality of the products by application tests, including the measurement some tests.
Naturalne węglany wapnia mają ogromne znaczenie w światowej gospodarce ze względu na ich liczne zastosowania, takie jak węglan wapnia w przemyśle papierniczym i malarskim. Produkty handlowe kalcytu muszą spełniać rygorystyczne wymagania jakościowe, które obecnie są trudne do osiągnięcia przez lokalnych producentów w Turcji. Dlatego duże ilości odpadów z przeróbki białego marmuru zostały przetransportowane do zakładów przemysłowych które wykorzystują kalcyt. Odpady marmurowe, znajdujące się w regionach Afyon i Kutahya, w środkowo-zachodniej Turcji, są ogólnie wykorzystywane do betonu i budowy autostrad. Możliwość wykorzystania odpadów marmurowych jest bardzo ważna dla rozwoju gospodarczego każdego kraju lub regionu. W artykule przedstawiono nową metodę oceny odpadów marmurowych jako krajowych zasobów kalcytu. Metoda służy jako przewodnik dla inwestorów i do podejmowania decyzji w branży kalcytu w Turcji. W artykule przedstawiono prace badawcze prowadzone w celu określenia jakości produktu - zmikronizowanego kalcytu z odpadów marmurowych oraz przegląd sytuacji rynkowej producentów regionalnych. Celem artykułu jest scharakteryzowanie czterech różnych odpadów marmurowych i określenie potencjału produkcji kalcytu o wymaganej jakości w Turcji. Zaproponowano kontrolę jakości produktów poprzez testy aplikacyjne, w tym pomiary niektórych parametrów.
Źródło:
Inżynieria Mineralna; 2020, 2, 1; 21-28
1640-4920
Pojawia się w:
Inżynieria Mineralna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of depressants in the selective flotation of smithsonite and calcite using potassium lauryl phosphate as collector
Autorzy:
Sun, Qing
Feng, Qiming
Shi, Qing
Powiązania:
https://bibliotekanauki.pl/articles/110635.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
smithsonite
calcite
flotation
depressant
separation
Opis:
In order to selectively separate smithsonite and calcite using potassium lauryl phosphate as collector and reveal the depression mechanism, the approaches of micro-flotation and zeta potential measurements were adopted. The effects of sodium hexametaphosphate (SHMP), water glass (WG), carboxymethyl cellulose (CMC) and lignosulfonate calcium (LSC) as depressants on smithsonite and calcite have been studied through micro-flotation. The single mineral flotation tests show that LSC can depress calcite, but it has little effect on smithsonite flotation. Flotation separation of a mixture of smithsonite and calcite can be completed to obtain a zinc concentrate grade up to 33.85% Zn with a recovery of 70.06%. The zeta potential results illustrate that LSC has higher tendency to be adsorbed on the surface of calcite. However, there is little adsorption of LSC on smithsonite.
Źródło:
Physicochemical Problems of Mineral Processing; 2019, 55, 1; 89-96
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of depressants in the selective flotation of smithsonite and calcite using cationic collector
Autorzy:
Liu, Hongjiang
Zhang, Guofan
Luo, Yuanjia
Powiązania:
https://bibliotekanauki.pl/articles/1449481.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
smithsonite
calcite
selective separation
depressant
Opis:
This work studied the effects of sodium hexametaphosphate (SHMP), tanning extract, water glass (WG) and calcium lignosulfonate (CLS) as depressants for the separation of smithsonite from calcite by using a cationic collector called octadecylamine acetate (ODA). Micro-flotation experimental tests showed that CLS can greatly and selectively depress calcite. When the dosages of CLS used were 20 and 40 mg/L, a concentrate with Zn grades of 42.54% and 49.32% and Zn recoveries of 81.66% and 68.00% was achieved in the flotation separation of mixed mineral (1:1 smithsonite:calcite). Zeta potential and adsorption measurements revealed that the adsorption of CLS on calcite’s surface was greater than that on smithsonite’s surface. When CLS was added, the adsorption of ODA was hindered greatly on the calcite’s surface but slightly on the smithsonite’s surface.
Źródło:
Physicochemical Problems of Mineral Processing; 2020, 56, 1; 1-10
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Calcium carbonate mineralization. Part II: effect of poly(ethylene glycol) and block copolymers molecular weight on formation of precipitate
Autorzy:
Polowczyk, I.
Bastrzyk, A.
Kozlecki, T.
Grzadka, E.
Sadowski, Z.
Powiązania:
https://bibliotekanauki.pl/articles/110696.pdf
Data publikacji:
2015
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
mineralization
block copolymers
PEG
calcite
Opis:
In this study the role of PEG and PEO-PPO-PEO block copolymers molecular weight in precipitation of calcium carbonate was examined. The CaCO3 particles were characterized by FTIR spectroscopy, X-ray, SEM and particle size distribution analysis. In absence and presence of modifiers, mixing of the reagents led to the formation of calcite crystals. The calcium carbonate obtained with poly(ethylene glycol) and block copolymers was characterized by smaller diameter in comparison with the one without modifiers. It was observed that using compounds with different molecular weights has no obvious effect on the form and properties of precipitated calcium carbonate particles.
Źródło:
Physicochemical Problems of Mineral Processing; 2015, 51, 2; 587-600
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Diagenetic alteration in low-Mg calcite from macrofossils : a review
Autorzy:
Ullmann, C. V.
Korte, C.
Powiązania:
https://bibliotekanauki.pl/articles/2059799.pdf
Data publikacji:
2015
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
diagenetic alteration
macrofossil calcite
isotopes
palaeoenvironment
Opis:
The quality of palaeoenvironmental reconstructions based on macrofossil carbonate critically depends on preservation of the shell material because post-depositional processes can modify its structural, chemical and isotopic composition, potentially overprinting or completely erasing palaeoenvironmental information. A suite of methods can be employed to evaluate the impact of diagenetic processes on the primary geochemical signatures of samples. Here we review the benefits and shortcomings of the most commonly employed optical (optical microscopy, cathodoluminescence microscopy, scanning electron microscopy) and chemical (trace element abundances, isotopic ratios) screening techniques used to assess the alteration degree of low-Mg calcite macrofossils and summarize the findings on diagenetic trends observed for elemental and isotopic systems in such materials. For a robust evaluation of the preservation state of biogenic calcite, it is advisable to combine a set of complementary techniques. Absolute limiting values of element and isotope ratios for discarding diagenetically altered materials cannot be universally applied, but should rather be evaluated on a case to case basis. The evaluation can be improved by analyses of diagenetic carbonate and altered fossil materials, which help constraining the diagenetic trajectories in the sampled specimens. Quantification of post-depositional alteration is possible, but in most cases the complexity of diagenetic systems hampers the possibility of retrieving original proxy values for palaeoenvironmental reconstructions from partially altered materials.
Źródło:
Geological Quarterly; 2015, 59, 1; 3--20
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Calcium carbonate mineralization. Part 1, The effect of poly(ethylene glycol) concentration on the formation of precipitate
Autorzy:
Polowczyk, I.
Bastrzyk, A.
Kozlecki, T.
Sadowski, Z.
Powiązania:
https://bibliotekanauki.pl/articles/110925.pdf
Data publikacji:
2013
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
calcium carbonate
calcite
vaterite
mineralization
PEG
Opis:
In this study, the role of polymer in precipitation has been examined by studying the effect of poly(ethylene glycol) (PEG) on the formation of calcium carbonate particles. The CaCO3 particles were characterized by several techniques, such as FTIR, XRD, SEM, and particle size distribution analysis. In the absence of polymer, the mixing of reagents in an aqueous solution led to the formation of calcite crystals. Introduction of poly(ethylene glycol) molecules reduced the rate of crystallization process, and the effect was concentration dependent. In the presence of 0.05, 0.1, and 0.5 % of PEG, after 5 minutes of precipitation initiation, vaterite microspheres appeared in the system and which were transformed into calcite crystals after 24 hours. The calcium carbonate obtained with PEG was characterized by smaller sized particles in comparison with the ones without polymer.
Źródło:
Physicochemical Problems of Mineral Processing; 2013, 49, 2; 631-639
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
High Porous Ceramic for Oil/Water Separation: Calcite as a Sintering Aid
Autorzy:
Abdulhameed, Mohammed Abdulmunem
Rahman, Mokdad Hayawi
Azziz, Haider Nadhom
Powiązania:
https://bibliotekanauki.pl/articles/27323841.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
porous ceramic membrane
sintering aid
calcite
Opis:
The effects of calcite (CaCO3) as sintering aid on the preparation of local aluminum silicate microfiltration membranes were characterized in terms of morphology, thermal shrinkage behavior, porosity, permeation performance, and pure water permeate flux for the membrane. Material selection is based on availability and formability. In order to create a suspension, an organic solvent (N-methyl-2-pyrrolidone) and a polymer binder were added to a mixture of aluminum silicate and calcium carbonate. The coagulant bath consisted of water, and the suspension was extruded into a hollow fiber using a spinneret. The membrane precursor is subjected to high temperatures up to 1250 °C and this process called the sintering process gets strong hollow fiber with high mechanical stability. The addition of the CaCO3 to the dispersion altered the structure of the resulting sintered membranes. The obtained finding demonstrates that carbon calcium addition to aluminum silicate has an affirmative on overall porosity in contrast to those made from purely natural aluminum silicate, as a result the aluminum silicate calcite ceramic microfiltration membrane, which had a high porosity of above 50%, shows the highest permeability of 35.8 ml m-2•s-1 and above 97% oil rejection when operating at 0.15 MPa trans-membrane pressure in oil-in-water separation experiments. The results show that low-cost aluminum silicate-calcite component of ceramic membranes and the manufactured ceramic microfiltration membrane can handle emulsified oily wastewater.
Źródło:
Journal of Ecological Engineering; 2023, 24, 7; 88--95
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The effect of the main component ratios in the joint filling on the product quality
Autorzy:
Rizaoğlu, Tamer
Karataş, Muhammed Ziya
Çoşkun, Canberk
Powiązania:
https://bibliotekanauki.pl/articles/27324350.pdf
Data publikacji:
2022
Wydawca:
Instytut Techniki Górniczej KOMAG
Tematy:
cement
joint filling
calcite
building materials
Opis:
When building materials are exposed to environmental and natural factors such as temperature differences, humidity, strong wind and earthquake in the areas where they are applied, irreversible damages such as separation, cracking and level difference occur in structures and building materials. In order to prevent these damages, the joints are left between the building materials and the gaps are filled with filling materials. The composition of the materials filling the joint gaps is also very important. The most important problems encountered in joint fillings are rupture, cracking and therefore permeability. In this study, it is aimed to compare the joint filling materials produced from different proportions of aggregate and white cement against rupture and cracking, and to determine the mixture ratio that exhibits the best performance. Five different recipes were prepared by using calcite powder as aggregate, white Portland cement as binder and water-repellent, volumizing and thickening chemical additives as auxiliary materials. On the prepared test samples; Capillary water absorption, water absorption by weight and volume, unit volume weight, saturated unit volume weight, porosity, compressive strength, bending strength, surface hardness and abrasion resistance tests were carried out. Considering the cost and environmental damage of cement, which is one of the main components in joint filler material, DD2 [Calcite (71.50%)] + White Cement (26.50%) + [Polymer + Cellulose + Plasticizer + Silicone] 2% has been detected as the most appropriate recipe.
Źródło:
Mining Machines; 2022, 40, 4; 180--190
2719-3306
Pojawia się w:
Mining Machines
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effective flotation separation of scheelite and calcite by applying methylene phosphonic acid sodium as a novel and green depressant
Autorzy:
Zhou, Hepeng
Wu, Handan
Guo, Jiangfeng
Tang, Xuekun
Huang, Wen
Luo, Xianping
Powiązania:
https://bibliotekanauki.pl/articles/24086193.pdf
Data publikacji:
2023
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
scheelite
calcite
inhibition mechanism
flotation separation
Opis:
It is known that the flotation separation of scheelite and calcite is quite difficult due to their similar surface properites. To slove the problem, ethylenediaminetetra (methylene phosphonic acid) sodium (EDTMPS), an environmentally friendly reagent, was employed as an efficient depressant for flotation separation of calcite for the first time. In flotation experiments, it demonstrates that EDTMPS could strongly inhibit the flotation of calcite but barely affect the flotaiton behavior of scheelite, showing excellent dpress ability and selectivity. Based on a series of measurements including contact angle analysis, zeta potential, and XPS analysis, it was found that large amout of EDTMPS could be absorbed on the surface of calcite through strong chemical chelation reaction and thus inhibiting the further adsorption of NaOL. On the contrary, little EDTMPS was absorbed on that of scheelite owing to the negatively charged tungstate ions on the surface in relative terms. All in all, these results exhibit EDTMPS has excellent selective inhibition ability on calcite, which can be potentially applied in actual scheelite and calcite flotation separation process.
Źródło:
Physicochemical Problems of Mineral Processing; 2023, 59, 3; art. no. 168517
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The effect of polyacrylic acid on the surface properties of calcite and fluorite aiming at their selective flotation
Autorzy:
Zhang, C.
Gao, Z.
Hu, Y.
Sun, W.
Tang, H.
Yin, Z.
He, J.
Guan, Q.
Zhu, Y.
Powiązania:
https://bibliotekanauki.pl/articles/110577.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
calcite
fluorite
selective flotation
polyacrylic acid
Opis:
In this study, the polyacrylic acid (PAA) was studied as a selective depressant for calcite in the selective flotation of fluorite and calcite, and the implications of this process for the separation of fluorite ore were studied using micro-flotation tests, and the results were analyzed with Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) analyses. The flotation tests indicated that the preferential adsorption of PAA onto calcite rather than sodium oleate (NaOl) could selectively depress the flotation of calcite, allowing its separation from fluorite at pH 7. The zeta potential of calcite became more negative with the addition of PAA rather than with NaOl. However, the characteristic features of PAA adsorption were not observed for fluorite, suggesting that NaOl preferentially adsorbed on the surface of fluorite, or that PAA could be replaced by NaOl on the fluorite surface. FT-IR and XPS analysis were utilized to obtain a better understanding of the mechanism by which PAA was more strongly adsorbed on the calcite surface than NaOl. This was revealed to occur through chemical bonding between the carboxyl group of PAA and the hydroxyl groups of the Ca species on the calcite surface, modifying the structure of the adsorbed layer. A possible adsorption mechanism, along with a postulated adsorption mode for the surface interaction between PAA and calcite, is proposed.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 3; 868-877
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental investigations of preparation of calcite particles by ultrasonic treatment
Autorzy:
Toraman, O. Y.
Powiązania:
https://bibliotekanauki.pl/articles/110407.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
calcite
fine particles
ultrasonic treatment
product size
Opis:
This paper investigates breakage of calcite powder (d50 = 25.23 μm) to fine particle sizes using an ultrasonic generator (400 W, 24 kHz). The present study focuses on comminution of calcite powder in water media by ultrasonic treatment and the effect of some operational parameters such as treatment time (5–30 min), ultrasonic power (30-100% as amplitude), solid ratio (5-30% w/w), probe positions (0.5-2 cm) and cycle on the product size. Experimental results were evaluated on the basis of average particle size (d50). Sonication of calcite produced a drastic particle-size reduction (d50=12.89 μm) under optimal conditions.
Źródło:
Physicochemical Problems of Mineral Processing; 2017, 53, 2; 859-868
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Flotation separation of scheelite from calcite using sodium polyacrylate as depressant
Autorzy:
Zhang, Y.
Chen, R.
Li, Y.
Wang, Y.
Luo, X.
Powiązania:
https://bibliotekanauki.pl/articles/110896.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
scheelite
calcite
flotation
sodium polyacrylate
selective depression
Opis:
The depressing properties of sodium polyacrylate (PA-Na) for calcite from scheelite were studied by microflotation experiments, zeta potentials, X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculation. Flotation results revealed that the selective depression effect of PA-Na was better than that of sodium silicate (Na2SiO3), and PA-Na can depress calcite more effectively than scheelite. The flotation recovery of scheelite and calcite kept at about 75% and 15% respectively at the pulp pH 9.3~9.6 and PA-Na concentration from 37.5 mg/dm3 to 50 mg/dm3. The zeta potentials of the minerals were significantly altered and the zeta potential of calcite became more negative than scheelite. XPS analysis deduced the occurrence of chemisorption between PA-Na and mineral surfaces, and the chemisorption of PA-Na on calcite was stronger than on scheelite. The results from DFT calculation demonstrated that the absolute value of the adsorption energy in the presence of PA-Na on the surface of calcite {104} was larger than on the surface of scheelite {111}. With the combination of the analysis, it could be concluded that calcite was more easily depressed than scheelite, and this finding remarkably matched with the microflotation experimental results. Furthermore, by using PA-Na as depressant, the flotation separation of scheelite from calcite can be achieved by controlling the flotation pH and PA-Na dosage.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 2; 505-516
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Studies on the carbonation of Czatkowice limestone in Calcium Looping process
Autorzy:
Tomaszewicz, G.
Kotyczka-Morańska, M.
Plis, A.
Powiązania:
https://bibliotekanauki.pl/articles/778245.pdf
Data publikacji:
2016
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
calcite
limestone
calcium looping
CO2
sorbent
Opis:
The growing demand for the reduction of anthropogenic CO2 emissions has stimulated the development of CO2 capture methods. One of the best capture methods comprises the calcium looping process, which incorporates calcium-based sorbents during the calcination and carbonation cycles. Czatkowice limestone may be considered to be a prospective chemical sorbent for the calcium looping process because of its formation characteristics. This paper addresses the thermogravimetric studies conducted under varying conditions of temperature and various concentrations of CO2 during the carbonation cycles. Moreover, a kinetic analysis of the carbonation stage was performed for the calcined sample at varying temperatures. The kinetic parameters for calcination and diffusion were determined. In addition, there was an increase in the concentration of CO2 with an increased carbonation conversion. The research results demonstrate that in further cycles of carbonation/calcination, the calcium sorbent reaches a higher rate of carbonation conversion with increased levels of CO2
Źródło:
Polish Journal of Chemical Technology; 2016, 18, 2; 53-58
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Enrichment of wollastonite with high calcite content
Autorzy:
Şavran, Ceyda
Türk, Tülay
Kangal, Murat Olgaç
Irgasheva, Ganjinakhon
Powiązania:
https://bibliotekanauki.pl/articles/2146878.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
wollastonite
calcite
flotation
magnetic separation
lankropol OPA
Opis:
Wollastonite plays a significant role as an industrial raw material in many fields; its exclusive properties mean that it is used in ceramics, paint, metallurgy and coatings. In nature, wollastonite mostly occurs with calcite. While the most common method for separating wollastonite from calcite is calcination, flotation is one of the methods for separating two minerals in a more economic, environmentally friendly way. In this study, the ore contains a large amount of calcite and augite, which is an iron bearing mineral that is subjected to magnetic separation, followed by flotation in order to obtain wollastonite and calcite concentrations individually. The SiO2, CaO and Fe2O3 contents in the ore are 28.00%, 48.20% and 0.45%, respectively. After magnetic separation has reduced the iron content, flotation experiments are carried out to find the optimum conditions. For the flotation process, the effect of particle size, pH and collector dosage are investigated. A wollastonite concentration of 84% purity is successfully achieved, with a 0.17% iron concentration under the optimal conditions of 100 micron particle size, pH 8 and 500 g/t collector dosage. The purity of the calcite is raised to 95% with the application of a cleaning stage.
Źródło:
Physicochemical Problems of Mineral Processing; 2022, 58, 5; art. no. 153058
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Quinic acid as a novel depressant for efficient flotation separation of scheelite from calcite
Autorzy:
Huang, Zheyu
Kuang, Jingzhong
Yu, Mingming
Ding, Dan
Powiązania:
https://bibliotekanauki.pl/articles/24085979.pdf
Data publikacji:
2023
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
quinic acid
scheelite
calcite
depression
selective adsorption
Opis:
There are difficulties to the conventional depressant for achieving separation of scheelite from calcite for the sake of their similar surface properties. The paper reported that a new depressant quinic acid (QA) was used for separating scheelite from calcite. The adsorption experiments, zeta potential experiment, contact angle, FTIR, XPS analysis and crystal chemistry analysis were utilized to known the depression mechanism of selectivity. The results showed that the recovery of calcite decreased drastically after QA added, whereas hardly influenced on scheelite. The tungsten concentrate could reach 66.24% WO3 grade and 89.46% recovery with 1.5×10-4 mol•L-1 QA at pH=9. The surface adsorption quantity of the QA on calcite was much greater than scheelite, which enhanced significantly the hydrophilicity of calcite surface. Due to its negative charge, QA could be adsorbed on the surface of calcite which had positive charge instead of that of scheelite with negative charge. Subsequently, free carboxyl groups of QA could chelated with Ca2+ species on the calcite surface to form stable chemical adsorption in order to prevent the Pb-BHA to form further adsorption on that, so there was no increase significantly on hydrophobicity. However, QA was obviously weak for adsorbing while Pb-BHA which could still be chemically adsorbed on scheelite surface of pre-treated with QA.
Źródło:
Physicochemical Problems of Mineral Processing; 2023, 59, 2; art. no. 166008
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence and mechanism of Zn2+ on fluorite/calcite in sodium hexametaphosphate flotation system
Autorzy:
Ruitao, Liu
Dan, Liu
Ruofan, Sun
Daqian, Wang
Wenkang, Zhang
Yuebing, Liu
Shuming, Wen
Powiązania:
https://bibliotekanauki.pl/articles/2175451.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
fluorite
calcite
sodium hexametaphosphate
flotation
metal ions
Opis:
Fluorite and calcite have similar surface properties and natural floatability, so their flotation separation has always been a problem faced by the beneficiation industry. The key to flotation separation is the choice of depressants. Sodium hexametaphosphate (SHMP) has a good effect on fluorite calcite selective inhibition. In this paper, the effects of Zn2+ on the selective inhibition of SHMP in the flotation process of fluorite and calcite were studied through single mineral and artificial mixed mineral flotation experiments. Solution chemical calculation, X-ray photoelectron spectroscopy (XPS), Fourier Transform Infrared spectroscopy (FT-IR) and Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS) analyses investigated the mechanism of action of Zn2+, which had the most significant negative effect on the selective inhibition of SHMP. The results show that the main components of SHMP inhibiting minerals are HPO42- and H2PO4-, which can react with Ca active sites on the mineral surface to form hydrophilic Ca(H22PO4)2 and CaHPO4, while Zn2+ The presence of HPO42- in solution resulted in the formation of stable ZnHPO4 complexes, thereby weakening the inhibitory effect of SHMP on minerals.
Źródło:
Physicochemical Problems of Mineral Processing; 2022, 58, 6; art. no. 151676
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multifrequency EPR study on radiation induced centers in calcium carbonates labeled with 13C
Autorzy:
Sadło, J.
Bugaj, A.
Strzelczak, G.
Sterniczuk, M.
Jaegermann, Z.
Powiązania:
https://bibliotekanauki.pl/articles/146101.pdf
Data publikacji:
2015
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
aragonite
calcite
dosimetry
EPR spectroscopy
γ-irradiation
radicals
Opis:
In calcite and aragonite, γ-irradiated at 77 K, several paramagnetic centers were generated and detected by EPR spectroscopy; in calcite, CO3 – (orthorhombic symmetry, bulk and bonded to surface), CO3 3–, NO3 2–, O3 –, and in aragonite CO2 – (isotropic and orthorhombic symmetry) depending on the type of calcium carbonate used. For calcium carbonates enriched with 13C more detailed information about the formed radicals was possible to be obtained. In both natural (white coral) and synthetic aragonite the same radicals were identifi ed with main differences in the properties of CO2 – radicals. An application of Q-band EPR allowed to avoid the signals overlap giving the characteristics of radical anisotropy.
Źródło:
Nukleonika; 2015, 60, No. 3, part 1; 429-434
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wstępne badania kalcytowej ceramiki porowatej metodą mikrotomografii komputerowej
Microcomputed tomography for evaluation of 3D calcite porous ceramics - preliminary report
Autorzy:
Jaegermann, Z.
Turżańska, K.
Michałowski, S.
Jabłoński, M.
Powiązania:
https://bibliotekanauki.pl/articles/284083.pdf
Data publikacji:
2007
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Polskie Towarzystwo Biominerałów
Tematy:
ceramika kalcytowa
struktury porowate
calcite ceramics
porous structures
Źródło:
Engineering of Biomaterials; 2007, 10, no. 65-66; 45-47
1429-7248
Pojawia się w:
Engineering of Biomaterials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Selective flotation of witherite from calcite using potassium chromate as a depressant
Autorzy:
Qiu, Yangshuai
Zhang, Lingyan
Jiao, Xuan
Guan, Junfang
Li, Ye
Qian, Yupeng
Powiązania:
https://bibliotekanauki.pl/articles/110784.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
witherite
calcite
selective flotation
sodium oleate
potassium chromate
Opis:
Witherite has been widely used as an industrial and environmental source of barium, with calcite being the primary associated carbonate mineral. However, few studies have been conducted to effectively concentrate witherite from barium ores. In this work, with the treatment of potassium chromate (K2CrO4) and sodium oleate (NaOL), witherite was selectively separated from calcite through selective flotation at different pH conditions. In addition, contact angle, Zeta potential, adsorption and X-ray photoelectron spectroscopy measurements were performed to characterize the separation mechanisms. The results demonstrated that NaOL had a strong collecting ability for both witherite and calcite; nevertheless, witherite could be effectively selected from calcite with the highest recovery at pH 9 in the presence of K2CrO4. From the XPS measurements, NaOL and K2CrO4 were found to be primarily attached to the surfaces of witherite and calcite through chemisorption. The presence of K2CrO4 on the surface of calcite adversely influenced the NaOL adsorption, which could make the flotation separation efficient and successful.
Źródło:
Physicochemical Problems of Mineral Processing; 2019, 55, 2; 565-574
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Homogenization phenomena of surface components of fluorite and calcite
Autorzy:
Sun, Ruofan
Liu, Dan
Zhang, Benyue
Lai, Hao
Wen, Shuming
Powiązania:
https://bibliotekanauki.pl/articles/1448969.pdf
Data publikacji:
2021
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
homogenization phenomena
surface composition
fluorite
calcite
mixed grinding
Opis:
The flotation separation of fluorite and calcite poses one of the most difficult problems in the mineral processing industry. In particular, the surface homogenization of fluorite and calcite worsens the result of fluorite flotation. In this paper, time of flight secondary ion mass spectrometry and principal component analysis are used to study the surface homogenization of fluorite and calcite during grinding and in solution using X-ray photoelectron spectroscopy, infrared spectroscopy, and solution chemical calculations. The results show that the surface composition of calcite converts to fluorite after mixed grinding and that the surface composition of fluorite also converts to calcite in clarified calcite solution.
Źródło:
Physicochemical Problems of Mineral Processing; 2021, 57, 1; 250-258
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of calcite and mica contents in nepheline syenite samples on the ceramic body sintering behaviours and surface roughness
Autorzy:
Durgut, Emrah
Cinar, Mustafa
Ozdemir, Orhan
Powiązania:
https://bibliotekanauki.pl/articles/2146930.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
nepheline syenite
calcite
mica
ceramic
sintering
surface roughness
Opis:
In this study, the effects of calcite and mica contents in nepheline syenite (NS) samples beneficiated by high intensity dry magnetic separation and flotation methods on ceramic bodies were investigated in detail. The NS samples were, first, sintered to observe the physical and surface roughness properties, and characterized based on the change of NS samples such as color, shrinkage, water absorption, and surface roughness after the sintering process. L-a-b color and Ra, Rz, Rt values for the NS samples were determined. The decrease in calcite and mica contents affected the surface of sintered specimens positively by reducing roughness values. Additionally, the water absorption values were found to be directly proportional to Ra values for unglazed surfaces. In conclusion, calcite and mica minerals in NS samples negatively affected surface quality by forming pinholes due to dehydroxylation and outgassing reactions in the sintering process.
Źródło:
Physicochemical Problems of Mineral Processing; 2022, 58, 5; art. no 149179
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of diethylenetriaminepenta pentasodium salt as an eco-friendly depressant to effectively improve the flotation separation of scheelite and calcite
Autorzy:
Zhou, Hepeng
Wu, Handan
Guo, Jiangfeng
Tang, Xuekun
Huang, Wen
Luo, Xianping
Powiązania:
https://bibliotekanauki.pl/articles/27323649.pdf
Data publikacji:
2023
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
flotation
scheelite
calcite
diethylenetriaminepenta pentasodium salt
depressant
adsorption
Opis:
Diethylenetriaminepenta (methylene-phosphonic acid) pentasodium salt (DTPMPA), an eco-friendly reagent, was tried for the first time as a depressant for flotation separation of scheelite from calcite. Micro-flotation tests show that DTPMPA can selectively depress the floatability of calcite. In contrast, DTPMPA barely affects the flotation behavior of scheelite. Based on the selective depress effect, floatation separation of scheelite and calcite can be effectively achieved by using DTPMPA as depressant in artificially mixed minerals flotation tests. Based on a series of measurements, it found the surface of calcite was positively charged due to the existence of Ca ion site, which can be chelated with –PO3H- functional group on the surface of DTPMPA. In the flotation process, DTPMPA can be chemically absorbed on the surface of calcite to inhibit further collector adsorption. On contrast, little DTPMPA was adsorbed on the surface of scheelite due to the spatial site resistance and electrostatic repulsion induced by surface WO42+. All in all, these results exhibit DTPMPA has excellent selective depression ability on calcite, which can be potentially applied in the actual scheelite flotation process.
Źródło:
Physicochemical Problems of Mineral Processing; 2023, 59, 6; art. no. 174718
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ordovician seawater composition : evidence from fluid inclusions in halite
Autorzy:
Meng, F.
Zhang, Y.
Galamay, A. R.
Bukowski, K.
Ni, P.
Xing, E.
Ji, L.
Powiązania:
https://bibliotekanauki.pl/articles/2059770.pdf
Data publikacji:
2018
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Ordovician
fluid inclusions
halite
seawater composition
calcite sea
Opis:
Fluid inclusions in halite can directly record the major composition of evaporated seawater; however, Ordovician halite is very rare. The Ordovician is a key time during the evolution history because profound changes occurred in the planet’s ecosystems. Marine life was characterized by a major diversification, the Great Ordovician Biodiversification Event and the Late Ordovician Mass Extinction, the first of the “big five” mass extinctions. However, so far there is no data on the Ordovician seawater. Data from the Ordovician-Silurian boundary were available only. In this study, we report the major compositions from Middle Ordovician halite in China to give the exact composition of Ordovician seawater. The basic ion composition (K+, Mg2+, Ca2+, and SO42-) of inclusion brines was established with the use of ultramicrochemical analysis. The data on the chemical composition of the brines in the primary inclusions indicated that the brines were of Na-K-Mg-Ca-Cl (Ca-rich) type, and cover a huge gap in the evolution of seawater chemistry. The chemical composition of the primary inclusion brine in halite confirmed the earlier results for the Cambrian and Silurian halite originating from other salt basins and the previous speculation of “calcite sea” during the Ordovician, indicating a higher potassium content in the Lower Paleozoic seawater than in the seawater of other periods of the Phanerozoic.
Źródło:
Geological Quarterly; 2018, 62, 2; 344--352
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Acidified water glass in the selective flotation of scheelite from calcite, Part I: performance and impact of the acid type
Autorzy:
Kupka, Nathalie
Möckel, Robert
Rudolph, Martin
Powiązania:
https://bibliotekanauki.pl/articles/109345.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
acidified water glass
scheelite calcite separation
froth flotation
Opis:
To improve the performance of sodium silicate in scheelite flotation and allow the selective separation of scheelite from other semi-soluble salt-type minerals such as calcite, three acids, sulfuric, oxalic and for the first time hydrochloric are used to acidify sodium silicate (also called water glass). A literature review of previous usage of acidified water glass shows that no comparison between acids was made before, that comparisons with alkaline water glass were limited and that the idea that acidified water glass is more efficient at lower dosages has not been proven in scheelite flotation. As a consequence, the impact of the acid type, the ratio between acid and sodium silicate and acid dosage is tested in single mineral flotation and batch flotation experiments. All three acids allow a higher performance of acidified water glass compared to alkaline water glass at lower dosages and with little addition of acid: the tungsten recovery and grade are improved while silicates and to a lesser extent calcium-bearing minerals float less. The dosage of acid is less determining than the mass ratio of the acid to sodium silicate, except in the case of hydrochloric acid. Overall, the acid type does not matter as all three acids perform well in flotation, whereby oxalic and hydrochloric acid are better.
Źródło:
Physicochemical Problems of Mineral Processing; 2020, 56, 2; 238-251
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The flotation separation of barite-calcite using sodium silicate as depressant in the presence of sodium dodecyl sulfate
Autorzy:
Chen, Xiong
Gu, Guohua
Liu, Donghui
Zhu, Renfeng
Powiązania:
https://bibliotekanauki.pl/articles/110272.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
flotation
calcite
barite
sodium dodecyl sulfate
sodium silicate
Opis:
The flotation separation of barite from calcite using sodium dodecyl sulfate (SDS) as the collector and sodium silicate (SS) as the depressant has been concretely studied in this paper. The results show that SDS has high collecting ability for both barite and calcite and that the flotation separation of barite from calcite cannot be achieved by using SDS alone. The depressant sodium silicate has a selective depression effect on calcite by the control of the pulp pH at 9.0 in the presence of SDS. Through locked cycle tests, a concentrate containing 95.54% BaSO4 can be obtained from an actual ore containing 24.5% BaSO4, with a recovery of 86.11%. The zeta potential measurements, adsorption analysis and infrared spectrum studies reveal that the pre-adsorption of sodium silicate strongly favors the adsorption of SDS on the calcite surface and adversely affects SDS adsorption on the barite surface. This property is the reason for the selective depression of SS on calcite.
Źródło:
Physicochemical Problems of Mineral Processing; 2019, 55, 2; 346-355
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Origin of calcite-cemented Holocene slope breccias from the Długa Valley (the Western Tatra Mountains
Autorzy:
Gradziński, M.
Jach, R.
Stworzewicz, E.
Powiązania:
https://bibliotekanauki.pl/articles/191437.pdf
Data publikacji:
2001
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
slope breccias
calcite cements
radiocarbon dating
Holocene
Tatra Mts.
Opis:
New locality of slope breccias was found in the Western Tatra Mts. It occures in the Długa Valley on a steep slope of ravine beneath the belt of Jurassic radiolarite cliffs. The brecccia consists of angular clasts of radiolarite bound with calcite cements. Void spaces between the clasts contain shells of Holocene snails. The cements are built of columnar crystals composed of acicular subcrystals and of skeletal crystals. The crystals grew rapidly from supersaturated solution due to CO2 degassing. Cementation occurred in vadose conditions in the Atlantcic Phase soon after the scree formation.
Źródło:
Annales Societatis Geologorum Poloniae; 2001, 71, No 2; 105-113
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Identification of sandstone-related rocks composition using the X-ray analysis
Autorzy:
Kosuth, M.
Powiązania:
https://bibliotekanauki.pl/articles/344037.pdf
Data publikacji:
2013
Wydawca:
nakł. Maciej Pawlikowski
Tematy:
X-ray analysis
mineral composition
sandstones
siltstones
calcite
dolomite
Opis:
The article presents knowledge based on investigation of sandstones or siltstones composition from the Paleogene flysch terrains in North-East Slovakia. Samples of frequently crumbling clastic rocks were commonly considered to be close to sandstones, composed by predominant quartz. The set of such samples, belonging to Dukla Unit Sandstones were analyzed using the XRD analyses. Beside of quartz the diffraction patterns gave the evidence in significant carbonate share with some minor to minute feldspars, mica and chlorite contents. Among majority of analyzed samples we distinguish three groups of sandstones: (1) with the abundant calcite admixture, (2) the sandstones which contain meaning dolomite portion. The group (3) is representing the samples is formed the same by quartz as by both of carbonates, each of them could form important up to prevailed mineral component. Comparison of analyzed samples mineral composition shows remarkable trend of higher calcite and dolomite contents in younger clastic sediments.
Źródło:
Auxiliary Sciences in Archaeology, Preservation of Relics and Environmental Engineering; 2013, 16; 1-7
1689-6742
Pojawia się w:
Auxiliary Sciences in Archaeology, Preservation of Relics and Environmental Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Celestite upgrading by jigs in presence of steel balls as ragging material
Autorzy:
Sobhy, Ahmed
El-Midany, Ayman A.
Ibrahim, Susan S.
Powiązania:
https://bibliotekanauki.pl/articles/1447020.pdf
Data publikacji:
2021
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
celestite
calcite
jigging
ragging material
gravity separation
statistical analysis
Opis:
Gravity separation using jigs is widely used for coarse particle sizes separation. However, fine sizes reduce jig performance. In this study, the upgrading of celestite ore by jig was investigated at different size fractions in the presence of ragging material. Three size fractions, i.e., -15+2 mm, - 2.0 + 0.50 mm and - 0.50 + 0.08 mm were used. The steel balls were used, as ragging material, to improve the separation of fines as well as to improve the concentrate quality. The statistical design was used to correlate celestite grade and recovery with studied operating variables, i.e., the ragging number of layers, ragging balls diameter, and separation time, at a fixed water flow rate and stroke length. The design results indicated that the ragging balls diameter and their number of layers play an important role. The smaller the ragging balls diameter and the higher the ragging number of layers are the better the concentrate grade but the longer the separation time. A celestite concentrate of (> 95% SrSO4) with 74.5% recovery was obtained for - 2.0 + 0.50 mm size fraction at the optimum conditions; i.e., 3.1 mm ragging balls diameter, one ragging layers, and 15 minutes separation time.
Źródło:
Physicochemical Problems of Mineral Processing; 2021, 57, 5; 118-128
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mineral carbonation of metallurgical slags
Autorzy:
Kasina, Monika
Kowalski, Piotr
Michalik, Marek
Powiązania:
https://bibliotekanauki.pl/articles/127572.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Mineralogiczne
Tematy:
blast furnace slag
steel making slag
mineral carbonation
calcite
Opis:
Due to increasing emissions of greenhouse gases into the atmosphere number of methods are being proposed to mitigate the risk of climate change. One of them is mineral carbonation. Blast furnace and steel making slags are co-products of metallurgical processes composed of minerals which represent appropriate source of cations required for mineral carbonation. Experimental studies were performed to determine the potential use of slags in this process. Obtained results indicate that steel making slag can be a useful material in CO2 capture procedures. Slag components dissolved in water are bonded as stable carbonates in the reaction with CO2 from ambient air. In case of blast furnace slag, the reaction is very slow and minerals are resistant to chemical changes. More time is needed for minerals dissolution and release of cations essential for carbonate crystallisation and thus makes blast furnace slags less favourable in comparison with steel making slag.
Źródło:
Mineralogia; 2014, 45, 1/2; 27-45
1899-8291
1899-8526
Pojawia się w:
Mineralogia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Acidified water glass in the selective flotation of scheelite from calcite, part II: species in solution and related mechanism of the depressant
Autorzy:
Kupka, Nathalie
Kaden, Peter
Jantschke, Anne
Schach, Edgar
Rudolph, Martin
Powiązania:
https://bibliotekanauki.pl/articles/1845224.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
acidified water glass
scheelite calcite separation
froth flotation
mechanism
Opis:
Sodium silicate is one of the main depressants against calcite and fluorite in the scheelite flotation industry. In the first part of this article, the authors acidified sodium silicate (AWG) with three acids (sulfuric, oxalic and hydrochloric) to improve its performance. Results showed that acidified water glass outperforms alkaline water glass in terms of selectivity: it increases mainly the grade by further depressing silicates and calcium-bearing minerals. In most cases, AWG requires lower dosages to do so. The effect of acidified water glass is evaluated through Mineral Liberation Analysis (MLA), froth analysis, Raman and Nuclear Magnetic Resonance (NMR) spectroscopy in order to hypothesize its mechanism. MLA shows that AWG affects silicates and sulfides more intensely than semi-soluble salttype minerals. Froth observations indicate other species in solution associated to the acid having an impact on the flotation results. Raman spectroscopy and NMR measurements indicate that the solution undergoes deep depolymerization when water glass is acidified. Lower molecular weight silica species, specifically Si-O monomers such as SiO(OH)3- will be responsible for the depression of the gangue minerals and are the drivers of the selectivity of AWG, more than orthosilicic acid. Depolymerization is more or less effective depending on the mass ratio of the acid to water glass and depending on the acid.
Źródło:
Physicochemical Problems of Mineral Processing; 2020, 56, 5; 797-817
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Value added industrial minerals production from calcite-rich wollastonite
Wartość dodana produkcji surowców przemysłowych ze złóż kalcytu i wollastonitu
Autorzy:
Bulut, Gülay
Akçin, Elif Suna
Kangal, Murat Olgaç
Powiązania:
https://bibliotekanauki.pl/articles/216790.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Instytut Gospodarki Surowcami Mineralnymi i Energią PAN
Tematy:
wollastonite
calcite
flotation
industrial minerals
wollastonit
kalcyt
flotacja
surowce przemysłowe
Opis:
The worldwide consumption of wollastonite has been increasing from day to day. It is a calcium metasilicate with the chemical formula CaSiO3. Wollastonite is the only naturally occurring, nonmetallic, white mineral that is needle-shaped in a crystal habit. Due to its high chemical and thermal resistance and nontoxic properties, wollastonite replaces asbestos. Apart from this, the acicular property of wollastonite allow it to compete with other acicular materials where improvements in dimensional stability, flexural modulus and heat deflection are sought. Due to its unique properties such as: its high brightness and whiteness, low moisture and oil absorption, low volatile content, and acicular properties, it is used also as a filling material for ceramics, plastics and paints, thermal and electrical insulator, wetting agent and smelter for glaze. Three methods are used for the beneficiation of wollastonite: mechanical sorting, dry or wet magnetic separation and flotation. Magnetic separation and flotation can be applied together in some cases. In this study, flotation has been investigated for the selective separation of calcite-rich wollastonite ores from the Buzlukdağ deposit, in the Kırşehir-Akpınar region, in the middle of Anatolia. The mineralogical analysis of the sample used in the study shows that the ore sample contains 60–62% wollastonite (CaSiO3), 4–5% augite (Ca,Na)(Mg,Fe,Al)(Si,Al)2O6, 30–32% calcite (CaCO3) and minor amount of other minerals. As a result of this study, the wollastonite concentrate which contains 0.44% Fe2O3, 52.71% SiO2, 87.85% wollastonite with 0.60% loss on ignition (using 1500 g/t potassium oleate) was obtained. The ultimate grade concentrates of calcite that can also be obtained as by-products are with 99.80% calcite content and 85.4% recovery.
Światowe zużycie wollastonitu ciągle wzrasta. Wollastonit jest metakrzemianem wapnia o wzorze chemicznym CaSiO3. Jest jedynym naturalnie występującym, niemetalicznym, białym minerałem, który ma kształt igieł o pokroju kryształu. Wollastonit ze względu na wysoką odporność chemiczną i termiczną oraz właściwości nietoksyczne zastępuje azbest. Poza tym igiełkowa właściwość wollastonitu umożliwia konkurencję z innymi igiełkowymi materiałami, w zakresie poprawy stabilności wymiarowej, modułu zginania i ugięcia pod wpływem ciepła. Ze względu na swoje unikalne właściwości, takie jak: wysoka jasność i biel, niska wilgotność i absorpcja oleju, niska zawartość części lotnych i właściwości igiełkowe, umożliwia zastosowanie jego jako: materiału wypełniającego do ceramiki, tworzyw sztucznych i farb, izolatora termicznego i elektrycznego, środka zwilżającego i pieca do glazury. Do wzbogacania wollastonitu stosowane są trzy metody: sortowanie mechaniczne, separacja magnetyczna na sucho lub mokro oraz flotacja. W niektórych przypadkach można zastosować zarówno separację magnetyczną, jak i flotację. W tym artykule zastosowano flotację w celu selektywnego oddzielania rud kalcytu i wollastonitu ze złoża Buzlukdağ w regionie Kırşehir-Akpınar w centrum Anatolii. Analiza mineralogiczna próbki użytej w badaniu pokazuje, że próba rudy zawiera 60–62% wollastonitu (CaSiO3), 4–5% augitu (Ca, Na)(Mg, Fe, Al)(Si, Al)2O6, 30–32% kalcytu (CaCO3) i niewielką ilość innych minerałów. W wyniku tych badań uzyskano koncentrat wollastonitu, który zawiera 0,44% ‒ Fe2O3, 52,71% ‒ SiO2, 87,85% wolastonitu przy stratach wynoszących 0,60% (przy użyciu 1500 g/Mg oleinianu potasu). Końcowe koncentraty kalcytu, które można również otrzymać jako produkty uboczne, zawierają 99,80% kalcytu i 85,4% odzysku.
Źródło:
Gospodarka Surowcami Mineralnymi; 2019, 35, 1; 43-58
0860-0953
Pojawia się w:
Gospodarka Surowcami Mineralnymi
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Temperature and isotopic relations in the Middle Miocene sandstones from the Ukrainian Carpathian Foredeep Basin - a reconnaissance study
Autorzy:
Jarmołowicz-Szulc, K.
Kozłowska, A.
Kuberska, M.
Powiązania:
https://bibliotekanauki.pl/articles/191662.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
isotopes
fluid systems
sandstones
calcite cement
Middle Miocene
Carpathian Foredeep
Ukraine
Opis:
Studies of the Middle Miocene sandstones in selected wells from the western Ukraine concerned calcite cements, both from isotopic and fluid inclusion aspects. The aim of the reconnaissance study was to find out inclusion – isotopic constraints for the calcite cements in the sandstones. The studied sandstones are subarkosic, sporadically sublithic arenites. The delta1318
Źródło:
Annales Societatis Geologorum Poloniae; 2011, 81, No 1; 79-86
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evidence of amorphous Ca-phosphate precipitate caused by bio mineralisation in 4-5th CE lime plasters of the previously submerged east coastal monument of Salvankuppam
Autorzy:
Singh, Manager R.
Kumar, S. Vinodh
Ganaraj, Kuntikana
Powiązania:
https://bibliotekanauki.pl/articles/2086560.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Mineralogiczne
Tematy:
Amorphous Ca-phosphate
16S rRNA
Bio-mineralization
calcite
lime plasters
Opis:
The lime plasters of the excavated monument of Salvankuppam, previously submerged and exposed by the Tsunami occurred in the Indian Ocean on 26th December 2004 was studied with different analytical techniques. The temple is dated 4-5th century CE. The XRF, XRD, FTIR, NMR, SEM-EDX analysis of the lime plasters evidenced particular occurrence of phosphatised bacterial remains in saline conditions. The formation of amorphous Ca-phosphate by bio mineralization was identified in the plasters by the analyses. The plasters are made of air-lime with coarse aggregates and seashells inclusion as confirmed by the thermal and chemical analysis. The microstructure and morphological investigations of mineralized microbial structures by SEM-EDX indicated the formation of amorphous Ca-phosphate. The unordered and fibrous spherulites have hardened and reduced porosity of the plaster by bio mineralization as observed through MIP analysis. The 16S rRNA sequencing has identified the Pseudomonas strains mainly responsible for the clustering of amorphous Ca-phosphate particles around the bacterial colony.
Źródło:
Mineralogia; 2021, 52, 1; 19--30
1899-8291
1899-8526
Pojawia się w:
Mineralogia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Tectonics of the Chęciny Anticline (Holy Cross Mts., Central Poland) in the light of new cartographic data and calcite vein analysis
Autorzy:
Jurewicz, E.
Stępień, U.
Powiązania:
https://bibliotekanauki.pl/articles/2058973.pdf
Data publikacji:
2012
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Holy Cross Mountains
Variscan folding
calcite veins
extensional fractures
faults
tectonic breccia
Opis:
The Variscan orogeny of NE–SW compression has folded the Paleozoic core of the Holy Cross Mountains (Central Poland). The Chęciny Anticline, formed during this tectonic event, is located in the southwestern part of the Kielce Unit. This paper presents structural data from two newly found outcrops of Cambrian rocks that modify the geometric reconstruction of the Chęciny Anticline, especially within its southern limb that is subdivided into two second-order structures: the Rzepka Syncline and the Wrzosy Anticline. The eastern part of the Chęciny Anticline has been reconstructed, pinpointing its fragmentation into a series of blocks (horsts and grabens) separated by faults semi-perpendicular to the anticline axis. New mapping data reveals deep, pre-Triassic erosion of folded Variscan basement, uncovering Cambrian rocks outcropping in the hinge of the Wrzosy Anticline. In the Chęciny Anticline, folding-related shortening has been accompanied by along-strike extension and the formation of syn-tectonic calcite veins, which filled fractures oriented perpendicular to the fold axis. The magnitude of extension has been estimated along a 215 m long main quarry wall of Rzepka Hill, approximately parallel to the Variscan structures and located within the southern limb of the Chęciny Anticline. The total thicknesses of veins filling extension fractures and spaces between clasts in tectonic breccia were summed and indicate 8.4% of strike-parallel extension (~120o) in the Chęciny area. This value was compared to ca. 30% of folding-induced shortening, related to NE–SW late Variscan compression. We hence obtain a strain ratio of 30:8.4 = 3.5. This high value of strain ratio indicates that longitudinal extension was a significant component contributing to the late Variscan deformation in the Kielce Unit.
Źródło:
Geological Quarterly; 2012, 56, 1; 95-106
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Strącanie cząstek węglanu wapnia w układzie gaz-ciecz w obecności wybranych sacharydów
Precipitation of calcium carbonate particles in a gas-liquid system in the presence of selected saccharides
Autorzy:
Konopacka-Łyskawa, D.
Czaplicka, N.
Powiązania:
https://bibliotekanauki.pl/articles/2073353.pdf
Data publikacji:
2018
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
węglan wapnia
kalcyt
wateryt
precypitacja
karbonatyzacja
calcium carbonate
calcite
vaterite
precipitation
carbonation
Opis:
Węglan wapnia strącano podczas karbonatyzacji roztworów zawierającego chlorku wapnia i amoniak. Procesy prowadzono w roztworach o pH powyżej 9. Jako dodatki wpływające na przebieg precypitacji stosowano glukozę lub sacharozę o stężeniach 15, 30 i 60 mM. Najwolniej precypitacja przebiegała, gdy roztwór zawierał najniższe stężenie glukozy. Wzrost stężenia badanych sacharydów skutkował skróceniem czasu precypitacji. Otrzymane cząstki CaCO3 były mieszaniną waterytu i kalcytu, a dodatek sacharydów spowodował zwiększenie zawartości kalcytu w produktach.
Calcium carbonate was precipitated during carbonation of solutions containing calcium chloride and ammonia. The processes were carried out at pH above 9. Glucose or sucrose at concentrations of 15, 30 and 60 mM were used as additives intluencing the course of precipitation. The slowest precipitation was observed in the solution containing the lowest glucose concentration. The increase of saccharides concentration resulted in a shorter precipitation time. The CaCO3 particles consisted of a mixture of vaterite and calcite, and the saccharides addition increased the calcite content in products.
Źródło:
Inżynieria i Aparatura Chemiczna; 2018, 3; 65--66
0368-0827
Pojawia się w:
Inżynieria i Aparatura Chemiczna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Selective Flotation of Barite and Associated Minerals: A Comparative Study
Flotacja barytu i minerałów towarzyszących: analiza porównawcza
Autorzy:
Kecir, M.
Kecir, A.
Powiązania:
https://bibliotekanauki.pl/articles/318431.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Przeróbki Kopalin
Tematy:
baryt
fluoryt
flotacja
odczynniki flotacyjne
pH
flotation
barite
fluorite
calcite
quartz
collector
Opis:
In the present socio-economical difficult context and with the oil prices fall, Algeria aims to develop its economy. For this purpose, it has to research, work and valorize not only its hydrocarbons resources, but also mineral ones, among which barite and fluorite, two industrial minerals of great importance. Because Algeria is a producer of gas and oil and a member of the OPEC, it needs important quantities of barite. This mineral plays a leading role in the oil industry, where it’s a major ingredient of the drilling muds. As for fluorite, it is essentially used as flux in metallurgy, especially as the country has a huge iron deposit in Gara Djebilet, with a potential of 2,5 billions tons, that will support the steel platform of Algeria. Particularly interesting areas with reserves of almost 300 000 tonnes of fluorite have been highlighted in the Hoggar in Sahara. In order to answer the requirements of the mentioned uses, barite and fluorite ores have to undergo an appropriate processing. The method here applied is flotation, during which different reagents, both anionic and cationic, have been tested in order to choose those who give the best results. The aim of our study is, in a first step, a systematic flotation behaviour of barite and associated minerals, during which various collectors, combined with modifiers have been tested. Then, an artificial mixtures flotation was carried out and all the optimal conditions of flotation were applied to barite and fluorite-barite ores. Definitive choice of optimal flotation requirements focused on Petronate L (1000 g/t ; pH 6.5) for barite flotation and on Flotbel R171A (100 g/t; pH 9) for fluorite, combined with potassium dichromate as depressing agent for quartz and barite. The final flotation treatment has led to the obtention of a barite concentrate with a 93,4% BaSO4 grade and a fluorite concentrate with 93,6% CaF2,both answering the users’ requirements.
W obecnej trudnej sytuacji socjoekonomicznej, w połączeniu ze spadkiem ceny ropy, Algieria jest nastawiona na rozwój ekonomiczny. W tym celu należy przeprowadzić badania, prace i waloryzację zasobów nie tylko surowców węglowodorowych, lecz również mineralnych, do których można zaliczyć baryt i fluoryt – dwa istotne minerały przemysłowe. Z racji tego, że Algieria prowadzi wydobycie gazu i ropy oraz jest członkiem OPEC, ma wysokie zapotrzebowanie na baryt. Minerał ten ma kluczowe znaczenie w przemyśle naftowym jako główny składnik iłowych płuczek wiertniczych. Fluoryt jest używany jako substancja zmiękczająca w metalurgii. Jest to istotne z powodu dużego złoża znajdującego się w tym kraju w GaraDjebilet, której zasoby sięgają 2,5 miliardy ton. Szczególnie interesujące tereny z zasobami fluorytu dochodzącymi do 300 000 ton mieszczą się w Hoggar na Saharze. W odpowiedzi na zapotrzebowanie przemysłu rudy barytu i fluorytu muszą być poddawane wzbogacaniu. Zastosowano flotację, podczas której badano odczynniki, zarówno anionowe jak i kationowe. Celem badań, w pierwszym etapie, było określenie wyników (efektów) flotacji barytu i minerałów towarzyszących, podczas której testowano różne kolektory wraz z ich modyfikatorami. Następnie przeprowadzono flotację sztucznych mieszanek oraz określono optymalne warunki flotacji rud barytu i fluorytu. Ostateczny wybór najlepszych parametrów technologicznych flotacji, został oparty na odczynniku zbierającym Petronate L (1000 g/t; pH=6,5) dla flotacji barytu oraz na Flotbel R171A (100 g/t; pH=9) dla fluorytu, w połączeniu z dichromianem potasu, jako czynnika depresyjnego dla kwarcu i barytu. Optymalny proces flotacji doprowadził do otrzymania koncentratu barytu z BaS04 na poziomie 93,4% i koncentratu fluorytu zawierającego 93,6% CaF2. Oba spełniają wymogi użytkowników.
Źródło:
Inżynieria Mineralna; 2015, R. 16, nr 2, 2; 117-124
1640-4920
Pojawia się w:
Inżynieria Mineralna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Preparation and characterization of calcite for tannic acid adsorption: Optimization by response surface methodology coupled by Box-Cox transformation procedure
Autorzy:
Tangarfa, Mariam
Hassani, Naoul Semlali Aouragh
Alaoui, Abdallah
Powiązania:
https://bibliotekanauki.pl/articles/1447160.pdf
Data publikacji:
2021
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
calcite
tannic acid
adsorption parameters
optimization
Response Surface Methodology
Box-Cox transformation
Opis:
Calcite depression is the most effective physicochemical process to valorize fluorine mineral. This process is achieved by adsorption of tannic acid, as the commonly used reagent, onto calcite. Adsorption investigation is very important in mineral processing. The present work focuses on optimization of physicochemical parameters of tannic acid adsorption onto calcite. Experimental study is carried out by a response surface methodology based on Box-Behnken design. Obtained results are exploited to develop a statistical model. Analysis of variance and residuals are performed to check the significance of tested models. Among these models, Cox-Box model predicts very well the obtained experimental data. This model shows that initial tannic acid concentration and solution pH as well as their interactions are the most significant parameters. Optimal conditions are achieved using the obtained statistical model. The present investigation is an important preliminary step to better understand calcite flotation behavior using tannic acid as a depressant.
Źródło:
Physicochemical Problems of Mineral Processing; 2021, 57, 3; 36-45
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Middle to Late Jurassic carbonate-biosiliceous sedimentation and palaeoenvironment in the Tethyan Fatricum Domain, Krížna Nappe, Tatra Mts, Western Carpathians
Autorzy:
Jach, Renata
Reháková, Daniela
Powiązania:
https://bibliotekanauki.pl/articles/191204.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
radiolarite
nodular limestone
Fleckenmergel facies
carbonate production crisis
calcite compensation depth
Tethys
Opis:
The Jurassic of the Alpine-Mediterranean Tethys was characterized by the formation of several interconnected basins, which underwent gradual deepening and oceanization. Sedimentation in each basin was influenced by a specific set of interrelated factors, such as tectonic activity, seawater circulation, climate, chemistry and trophic state of seawater as well as evolutionary changes of the marine biota. This paper deals with the Fatricum Domain (Central Carpathians, Poland and Slovakia), which in the Jurassic was a pull-apart basin on a thinned continental crust. The sedimentation history of this domain during the Bajocian-Tithonian and its governing factors have been revealed. Facies analysis of the Bajocian-Oxfordian deposits evidences considerable relief of the basin-floor topography. Deposits in the Western Tatra Mts represent sedimentation on a submarine intrabasinal high, whereas the coeval deposits of the eastern part of the Tatra Mts accumulated in a deeper basin. The basin succession began with Bajocian bioturbated “spotted” limestones and siliciclastic mudstones (Fleckenmergel facies). These were succeeded by uppermost Bajocian - middle Bathonian grey nodular limestones, affected by synsedimentary gravitational bulk creep. The coeval deposits of the intrabasinal high are represented by well-washed Bositra-crinoidal limestones with condensed horizons. Uniform radiolarite sedimentation commenced in the late Bathonian and persisted until the early late Kimmeridgian. The basal ribbon radiolarites (upper Bathonian - lower Oxfordian), which consist of alternating chert beds and shale partings, are a record of seawater eutrophication, a related crisis in carbonate production and the rise of the CCD, which collectively resulted in biosiliceous sedimentation. The overlying calcareous radiolarites (middle Oxfordian - lowermost upper Kimmeridgian) marked a gradual return to carbonate sedimentation. The return of conditions that were favourable for carbonate sedimentation took place in the late Kimmeridgian, when the red nodular limestones were deposited. They are partly replaced by basinal platy limestones (uppermost Kimmeridgian - Tithonian) in the Western Tatra Mts. This lateral variation in facies reflects a change in the sedimentary conditions governed by a bathymetric reversal of the seafloor configuration, attributed to a further stage in the pull-apart transcurrent tectonics of the Fatricum Domain.
Źródło:
Annales Societatis Geologorum Poloniae; 2019, 89, 1; 1-46
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Water contact angle on corresponding surfaces of freshly fractured fluorite, calcite and mica
Autorzy:
Kowalczuk, P. B.
Akkaya, C.
Ergun, M.
Janicki, M.
Sahbaz, O.
Drzymala, J.
Powiązania:
https://bibliotekanauki.pl/articles/110595.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
contact angle
surface properties
cleaving plane
surface composition
corresponding halves
fluorite
calcite
mica
Opis:
Advancing and receding contact angles of water with corresponding surfaces of freshly fractured calcite, fluorite and mica were measured. The corresponding surfaces were obtained by mechanical splitting of a small lump of each mineral into two pieces. Theoretical considerations revealed that depending on the mineral cleaving plane, surfaces created by splitting into halves can be either identical or entirely different as far as their surface chemical composition is concerned. It was experimentally established that receding and advancing contact angles measured on the corresponding surfaces of fluorite, calcite and mica were identical for the sessile drop method. When the contact angle was measured by the captive bubble approach, there were small differences in the contact angles measured on the corresponding surfaces of fluorite. It was most probably due to surface irregularities and roughness, and therefore different times needed to rupture the liquid film between the bubble and solid surface.
Źródło:
Physicochemical Problems of Mineral Processing; 2017, 53, 1; 192-201
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Właściwości i zastosowanie kalcytu w przemyśle
Properties and industrial uses of calcite
Autorzy:
Bartczak, Martyna
Powiązania:
https://bibliotekanauki.pl/articles/24085341.pdf
Data publikacji:
2023
Wydawca:
Stowarzyszenie Menedżerów Jakości i Produkcji
Tematy:
kalcyt
węglan wapnia
zastosowanie w przemyśle
ceramika
szpat
calcite
calcium carbonate
industrial uses
ceramics
Opis:
Kalcyt jest pospolitym minerałem skałotwórczym z grupy węglanów o składzie chemicznym węglanu wapnia (zwany również kalcytem lub podwójnym drzewcem i alternatywnie pisany kalcytem). Należy do ogólnej kategorii minerałów węglanów i azotanów. Swoją nazwę zawdzięcza połączeniu dwóch słów – greckiego chalix i łacińskiego calx, co oznacza wapno. Minerał ten jest jednym z najczęstszych składników kamieniotwórczych, którego kryształy tworzą m.in. wapienia, marmury i oolity. Występuje w wielu kolorach na całym świecie i stanowi ponad 4% światowej gleby. Kalcyty w czystej postaci są kolorowe i przezroczyste. Aragonit i dolomit są pod wieloma względami bardzo podobne do środowiska geologicznego kalcytu. Minerał ten znajduje zastosowanie w wielu dziedzinach naszego życia a jego wydobycie sięga już początku XX wieku (na Wyżynie Krakowsko-Częstochowskiej). Artykuł ma na celu przedstawienie wybranych zastosowań kalcytu oraz opisanie jego właściwości.
Calcite is a common rock-forming mineral from the carbonate group with the chemical composition of calcium carbonate. It belongs to the general category of carbonate and nitrate minerals. It owes its name to a combination of two words - the Greek chalix and the Latin calx, which means lime. This mineral is one of the most common stone-forming ingredients, whose crystals form e.g. limestones, marbles and oolites. It comes in many colors around the world and makes up over 4% of the world's soil. Pure calcites are colored and transparent. Aragonite and dolomite are in many respects very similar to the geological environment of calcite. This mineral is used in many areas of our lives and its extraction dates back to the beginning of the 20th century (in the Kraków-Częstochowa Upland). The article aims to present selected applications of calcite and describe its properties.
Źródło:
Archiwum Wiedzy Inżynierskiej; 2023, 8, 1; 15--17
2544-2449
Pojawia się w:
Archiwum Wiedzy Inżynierskiej
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Biomateriały implantacyjne dotowane srebrem – próby wstępne. Cz.2 – Materiały kalcytowe
Silver containing biomaterials – preliminary studies. Part 2 – Calcite implants
Autorzy:
Jaegerman, Z.
Michałowski, S.
Ciołek, L.
Wiśniewski, Z.
Powiązania:
https://bibliotekanauki.pl/articles/392272.pdf
Data publikacji:
2015
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Ceramiki i Materiałów Budowlanych
Tematy:
implant
biomateriał
węglan wapnia
kalcyt
bakteriobójczość
nanosrebro
biomaterial
calcium carbonate
calcite
antimicrobial activity
nanosilver
Opis:
Niniejszy artykuł jest kontynuacją opisu badań biomateriałów dotowanych srebrem, który został zamieszczony w poprzednim (22) numerze „Prac Instytutu Ceramiki i Materiałów Budowlanych”. Głównym celem prac badawczych było opracowanie wstępnych założeń otrzymywania wszczepialnych materiałów kalcytowych wykazujących działanie przeciwbakteryjne. Do przygotowania materiałów kalcytowych wykorzystano tworzywo ceramiczne na bazie węglanu wapnia, a jako źródła nanosrebra użyto dwóch rodzajów bioszkieł ze srebrem, opracowanych w Instytucie Ceramiki i Materiałów Budowlanych. Do badań przygotowano 8 próbek tworzyw kalcytowych zawierających różne ilości bioszkieł. Oznaczono ich gęstość pozorną, porowatość całkowitą i wytrzymałość na ściskanie. Wykonano badania mikrostruktury przy użyciu skaningowego mikroskopu elektronowego oraz badania działania przeciwbakteryjnego z wykorzystaniem bakterii Pseudomonas aeruginosa oraz Staphylococcus aureus. Przeprowadzone badania pokazały, że zarówno ilość, jak i rodzaj dodawanego bioszkła mają wpływ na właściwości fizyczne materiałów. Obserwacje mikrostruktury materiałów zawierających bioszkła wykazały, że ziarna bioszkieł w temperaturze spiekania materiału kalcytowego (510°C) nie łączą się z ziarnami kalcytowymi. Zjawisko to może być jedną z przyczyn obniżania wytrzymałości na ściskanie ze wzrostem zawartości bioszkła w materiale. Wyniki badania bakteriobójczości wskazały na zdecydowane obniżenie ilości bakterii dla obu materiałów kalcytowych w stosunku do hodowli kontrolnej w każdym okresie inkubacji. Przeprowadzone badania wykazały, że zastosowana metoda dotowania materiałów kalcytowych srebrem pozwala na otrzymanie materiałów wykazujących działanie przeciwbakteryjne.
The article is the continuation of description of research on silver containing biomaterials, published in the previous issue of „Prace ICiMB”. The main objective of the research was to develop initial assumptions on the production of calcite implants showing antibacterial activity. Ceramic material based on calcium carbonate, as well as two types of silver containing bioglasses developed in ICiMB were used in the preparation of calcite materials. Eight test calcite samples containing different amounts of bioglasses were prepared. Apparent density, total porosity and compressive strength were determined. Analysis of materials microstructure using scanning electron microscopy and study of antimicrobial activity using Pseudomonas aeruginosa and Staphylococcus aureus bacteria were performed. The studies showed that both the content and type of bioglass affect the physical properties of the materials. Microscopic observations showed that grains of bioglass do not sinter in the temperature of 510°C, that corresponds to the sintering temperature of calcite material. This phenomenon can be one of the reasons that compressive strength decreases with the increase of the content of bioglass in the material. Analysis of bactericidal effect showed a significant reduction of the bacteria count for both calcite materials in comparison to the control culture, at all periods of incubation. The results of the study have shown that the method of silver doping of calcite materials allows to obtain implants with antibacterial activity.
Źródło:
Prace Instytutu Ceramiki i Materiałów Budowlanych; 2015, R. 8, nr 23, 23; 28-38
1899-3230
Pojawia się w:
Prace Instytutu Ceramiki i Materiałów Budowlanych
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Kalcyty blokowe ze szczelin tektonicznych w piaskowcach płaszczowiny magurskiej (Karpaty Zewnętrzne) - wstępne wyniki badań
Blocky calcites from tectonic fractures hosted in sandstones of the Magura Nappe (Outer Carpathians) - preliminary results
Autorzy:
Duś-Picheta, A.
Powiązania:
https://bibliotekanauki.pl/articles/183956.pdf
Data publikacji:
2008
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
żyły kalcytu blokowego
cementacja piaskowców
płaszczowina magurska
blocky calcite veins
sandstone cementation
Magura Nappe
Opis:
Badano żyły kalcytu blokowego wypełniające szczeliny ciosowe. Opróbowano piaskowce oraz żyły kalcytowe w strefie raczańskiej (Gruszowiec) oraz w strefie Siar (Ropica Górna 1, Ropica Górna 2) płaszczowiny magurskiej. Celem badań było określenie relacji pomiędzy kalcytem blokowym z żył i stopniem utwardzenia piaskowców otaczających. Badania petrograficzne płytek cienkich uzupełniono badaniami chemicznymi oraz obserwacjami w katodoluminescencji. Badane kalcyty blokowe charakteryzują się różnym stopniem żelazistości. Intensywność ich luminescencji pozytywnie koreluje się z zawartością Mn2+. Na podstawie wyników analizy kontaktów międzyziarnowych w piaskowcach oraz relacji żył do cementów i ziaren w piaskowcach stwierdzono, że żyły kalcytu blokowego powstawały na różnym etapie utwardzenia skał płaszczowiny magurskiej. Mikrostruktury oraz różny stopień żelazistości kalcytów blokowych mogą być użyte jako wskaźniki kierunku cementacji szczelin tektonicznych.
Blocky calcite veins filling joints have been studied in sandstones. Calcite veins and host sandstones were sampled in Raca Unit (exposure Gruszowiec) and in Siary Unit (exposures Ropica Górna 1 and Ropica Górna 2). The aim of these studies was to define relationship between blocky calcite in veins and progress of sandstone induration. In the paper, petrographic study was supplemented by chemical analyses and cathodoluminescence observations. Studied blocky calcites show different Fe contents. Intensity of blocky calcite luminescence shows a good correlation with Mn2+ contents. Based on results of grain-contact analysis in sandstones and on relationship between veins and cement in sandstones as well as framework grains, it is concluded that blocky calcite veins were formed in rocks showing different stage of induration. Microstructures and differentiation in Fe contents in blocky calcite may be used as indicators of direction filling in tectonic fractures.
Źródło:
Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie; 2008, 34, 3; 561-571
0138-0974
Pojawia się w:
Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Badania procesu spiekania aragonitu i kalcytu w obecności fluorku litu
Research on the sintering process of aragonite and calcite in the presence of lithium fluoride
Autorzy:
Jaegermann, Z.
Szterner, P.
Tymowicz-Grzyb, P.
Piątek, M.
Powiązania:
https://bibliotekanauki.pl/articles/168974.pdf
Data publikacji:
2018
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Ceramiki i Materiałów Budowlanych
Tematy:
aragonit
kalcyt
fluorek litu
spiekanie
badania termiczne
aragonite
calcite
lithium fluoride
sintering
thermal analysis
Opis:
W pracy przedstawiono wyniki badań nad spiekaniem dwóch odmian krystalograficznych węglanu wapnia: aragonitu i kalcytu, z dodatkiem fluorku litu. Aby prześledzić zjawiska termiczne zachodzące podczas ogrzewania, wykonano badania jednoczesnej analizy termicznej TG/DTA próbek modelowych. Oznaczenie zmian wymiarów liniowych próbek przeprowadzono wykonując badania dylatometryczne, a obrazy morfologii proszków i mikrostruktury materiałów wykonano przy użyciu mikroskopu skaningowego. Wyniki wykonanych badań wykazały, że procesy spiekania aragonitu i kalcytu przebiegają w zbliżony sposób. Podstawową różnicę stanowi zjawisko rozszerzania próbki aragonitu w temp. ok. 330°C, związane prawdopodobnie z przemianą fazową aragonit/kalcyt, co nie ma widocznego wpływu na temperaturę maksymalnej szybkości zmian wymiarów liniowych, ani na poziom zagęszczenia materiałów po wypaleniu.
The paper presents results of study of sintering process of two crystallographic forms of calcium carbonate: aragonite and calcite, doped with lithium fluoride. To investigate the thermal phenomena occurring during heating, simultaneous thermal analysis of model samples were carried out. Determination of changes in linear dimensions of the samples was made by dilatometric tests. Microstructure images were taken using the scanning microscope. The results of the tests showed that sintering processes of aragonite and calcite run in a similar manner. The main difference is the phenomenon of aragonite expansion at approx. 330°C, probably related to aragonite/calcite phase transformation, which has no effect on temperature of the maximum rate of change in linear dimensions, nor on the densification degree after firing.
Źródło:
Szkło i Ceramika; 2018, R. 69, nr 4, 4; 15-19
0039-8144
Pojawia się w:
Szkło i Ceramika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Miocene transpression effects at the boundary of Central Carpathian Paleogene Basin and Pieniny Klippen Belt - examples from Polish-Slovakian borderland
Autorzy:
Ludwiniak, M.
Powiązania:
https://bibliotekanauki.pl/articles/184548.pdf
Data publikacji:
2018
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
structural geology
tectonics
Western Central Carpathians
Podhale basin
Spišska Magura
faults
folds
joints
calcite veins
Opis:
A geological structural study has been conducted along the tectonic contact zone of the Central Carpathian Paleogene Basin (CCPB) and Pieniny Klippen Belt (PKB) in the eastern Podhale and western Spišska Magura areas. It concerned mostly the Central Carpathian Paleogene flysch strata and, to a lesser degree, the Upper Cretaceous rocks of the PKB. Tectonic deformation structures genetically related to the important tectonic boundary in question occur within a c. 1.5–2 km-wide strip of the Paleogene flysch rocks adjacent from the south to the PKB. Two parallel structural domains have been distinguished within this strip: the contact zone proper in the north and the peri-Pieniny monocline in the south. Most of the minor faults documented in the Paleogene flysch bear a record of dextral motion parallel to the contact zone. Some dextral-reverse oblique slip faults of NE-SW and W-E trends have also been recognized. Discrepancies in the orientation and sense of movement on strike-slip faults in the Paleogene flysch rocks and those in marlstones of the “klippen envelope” of the PKB were encountered. They probably reflect differences in the structural history of both the adjacent rock complexes, as the Upper Cretaceous deposits of the PKB must have experienced more deformation events and, in general, were affected by much more intense strain than those of the CCPB. Contractional structures, such as south-vergent reverse faults and recumbent folds which point to ca N-S tectonic shortening, have also been found in the Paleogene rocks. The entirety of the structural features found in the CCPB is characteristic of a transpressional regime. The regionally consistent coexistence of structures resulting from strike-slip movements and tectonic shortening, as well as features pointing directly to a transpressional regime, prove the transpressional dextral nature of the contact between the CCPB and PKB.
Źródło:
Geology, Geophysics and Environment; 2018, 44, 1; 91-100
2299-8004
2353-0790
Pojawia się w:
Geology, Geophysics and Environment
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Surface Characterization of Oleic Acid Coated Marble Dust
Charakterystyka powierzchni pyłu marmurowego pokrytego kwasem oleinowym
Autorzy:
Polat, Ercan
Guler, Taki
Celep, Oktay
Akturk, Selçuk
Powiązania:
https://bibliotekanauki.pl/articles/318754.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Przeróbki Kopalin
Tematy:
surface modification
oleic acid
marble waste
micronized calcite
modyfikacja powierzchni
kwas olejowy
odpady marmurowe
mikronizowany kalcyt
Opis:
Calcite, being the most abundant mineral on earth crust, have wide application areas especially in polymer industry as a micronized functional filler material. It is hydrophilic in natural form, and made hydrophobic after surface modification to meet the requirements of polymer industry: the incompatibility between high energetic hydrophilic surface of calcite and the low-energy surface of hydrophobic polymers is a major problem. Treatment of micronized calcite with fatty acids is one of the most common method to obtain modified mineral surface. In present study, oleic acid (OA), fatty acid type surface modifying agent was used for the surface characterization of OA coated marble dust. Fine tailings of slab cutting unit of a marble processing plant was supplied. The sample was subjected to wet classification process to obtain micronized calcite fraction for experimental works. Surface modification of finely sized fraction was performed in a laboratory type flotation unit. Thermogravimetric analysis (TGA) and Transmission Electron Microscopy (TEM) were used as characterization techniques.
Kalcyt, będący najczęściej występującym minerałem w skorupie ziemskiej, ma szerokie obszary zastosowań, szczególnie w przemyśle polimerowym, jako mikronizowany funkcjonalny materiał wypełniający. Jest hydrofilowy w naturalnej postaci, a po modyfikacji powierzchni stał się hydrofobowy, aby spełnić wymagania przemysłu polimerów: niekompatybilność między wysokoenergetyczną hydrofilową powierzchnią kalcytu a niskoenergetyczną powierzchnią hydrofobowych polimerów jest poważnym problemem. Obróbka mikronizowanego kalcytu kwasami tłuszczowymi jest jedną z najczęstszych metod uzyskiwania modyfikowanej powierzchni mineralnej. W niniejszym badaniu do charakteryzowania powierzchni pyłu marmurowego pokrytego OA - kwasem oleinowym (OA), jako środek modyfikujący powierzchnię użyto kwasu tłuszczowego. Do badań wykorzystano drobne odpady z urządzenia do cięcia płyt w zakładzie przeróbki marmuru. Próbkę poddano procesowi mokrej klasyfikacji w celu uzyskania mikronizowanej frakcji kalcytu do prac eksperymentalnych. Modyfikację powierzchni frakcji drobnej wielkości przeprowadzono w laboratoryjnej jednostce flotacyjnej. Jako do scharakteryzowana próbek zastosowano analizę termograwimetryczną (TGA) i transmisyjną mikroskopię elektronową (TEM).
Źródło:
Inżynieria Mineralna; 2020, 1, 1; 125-129
1640-4920
Pojawia się w:
Inżynieria Mineralna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
High-resolution Campanian-Maastrichtian carbon and oxygen stable isotopes of bulk-rock and skeletal components: palaeoceanographic and palaeoenviron-mental implications for the Boreal shelf sea
Autorzy:
Wilmsen, M.
Niebuhr, B.
Powiązania:
https://bibliotekanauki.pl/articles/139424.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Cretaceous
northern Germany
stable isotopes
low-magnesium calcite
palaeoceanography
kreda
Niemcy Północne
izotopy stabilne
kalcyt
paleoceanografia
Opis:
A high-resolution latest Early Campanian to Early Maastrichtian carbon and oxygen stable isotope record from the northern German Boreal shelf sea based on 537 analyses of co-occurring belemnites, brachiopods, inoceramids, oysters, and bulk rock samples is presented. All samples are precisely related to their stratigraphic, systematic and facies backgrounds and form an integrated, nearly 10-myr-long dataset with considerable palaeoenvironmental and palaeoceanographical implications. Petrographic studies indicate that low-magnesium calcitic coccoliths and calcispheres (i.e., planktic carbonate) predominate the bulk-rock data (marl-limestone rhythmites and chalks), thus representing a sea-surface water signal, and that only minor diagenetic alteration of the carbonate muds took place. Based on TL and CL microscopy, the investigated belemnites are extraordinarily well preserved, which may in part be explained by their early diagenetic surficial silicification (container effect), while the other macroinvertebrate groups are all less well preserved. The (plankton-dominated) δ13C values of the marl-limestone rhythmites and chalks (+1.1 to +2.5‰), recording a surface water signal, compare well with the δ13C data of inoceramids while δ13C brach.values (+1.5 to +3.0‰) are heavier than the bulk rock data. The large variation in the δ13Cbel. (-0.1 to +3.6‰) is attributed to isotopic disequilibrium of the biogenic carbonate formed by the belemnite animal. The bulk rock δ18O values show a remarkable low scatter, supporting petrographic observation of only minor diagenetic stabilisation/cementation, and can be approximated with northern German shelf sea-surface temperatures of ca. 20°C for the Late Campanian (ca. -2‰ δ18O), being slightly cooler during the Early Maastrichtian. The δ18O values of the belemnite rostra are even less variable and quite rich in heavier 18O (-0.7 to +0.6 with a mean of -0.1‰ δ18Obel.) in comparison to bulk rock and other skeletal components. Based on their excellent microstructural preservation and non-luminescence, we conclude that the belemnite rostra are diagenetically unaltered and have preserved the primary δ18O signal of ambient seawater (12±2°C). In the absence of any indication for migration from cooler water masses and evidence for authochtonous populations we assume that the belemnites of the genera Belemnitella and Belemnella lived as nektobenthos near the sea-floor and thus record the temperature of the bottom mixed layer of the seasonally weakly stratified north German shelf sea at water depths of 100 to 150 m; the temperature gradient was thus 12.5–18.75 m/1°C. A conspicuous latest Campanian cooling event is evident in both sea-surface and bottom-water temperatures. The δ18O values of nearly all investigated benthic fossils lie between the isotope values of pristine belemnites and bulk rock, and, therefore, should be used for palaeotemperature reconstructions only with great care.
Źródło:
Acta Geologica Polonica; 2017, 67, 1; 47-74
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Odmiany polimorficzne CaCO3 jako produkt karbonatyzacji zaczynów cementowych
Polymorphic varieties of CaCO3 as a product of cement grout carbonization
Autorzy:
Uliasz-Bocheńczyk, A.
Gawlicki, M.
Mokrzycki, E.
Pyzalski, M.
Powiązania:
https://bibliotekanauki.pl/articles/216610.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Instytut Gospodarki Surowcami Mineralnymi i Energią PAN
Tematy:
zaczyn cementowy
karbonatyzacja
korozja węglanowa
kalcyt
aragonit
vateryt
cement grout
carbonization
carbonate corrosion
calcite
aragonite
vaterite
Opis:
Zaczyny cementowe stosowane w technologiach wiertniczych wykorzystywanych w geologicznym składowaniu CO2 będą ulegać intensywnej karbonatyzacji. Ditlenek węgla powodujący korozję węglanową lub kwasowo-węglanową zaczynu cementowego reaguje przede wszystkim z portlandytem Ca(OH)2, stanowiącym obok uwodnionych krzemianów wapnia C-S-H główny produkt reakcji z wodą podstawowych składników cementu, alitu i belitu. Węglan wapnia powstający w wyniku reakcji CO2 z Ca(OH)2 może występować we wszystkich trzech odmianach polimorficznych CaCO3, jako kalcyt, aragonit i vateryt. Potwierdziły to badania próbek pobranych z otworów wykonanych w celu intensyfikacji wydobycia ropy naftowej przy użyciu CO2 (Carem i in. 2006, 2007; Scherer, Huet 2009). Prawdopodobnie jako pierwszy powstaje vateryt, który następnie przechodzi w kalcyt. Aragonit pojawia się zazwyczaj jako faza przejściowa (Kurdowski 2010). W artykule przedstawiono wyniki badań składów fazowych zaczynów cementowych, które mogą być użyte w pracach wiertniczych wykonywanych w celu geologicznego składowania CO2. W zaczynach stwierdzono równoczesne występowanie obok siebie różnych odmian polimorficznych węglanu wapnia. Zaczyny pozostające w kontakcie z solanką i ditlenkiem węgla wykazywały oprócz kalcytu, aragonitu i vaterytu, również obecność faz będących produktami korozji chlorkowej zaczynu cementowego.
Cement grouts used in drilling technologies applied in the geological storage of CO2 undergo intense carbonization. Carbon dioxide, which causes carbonate or acid-carbonate corrosion of a cement grout, reacts mainly with portlandite Ca(OH)2 which is, along with hydrate calcium silicate C-S-H, a main product of basic cement components’ (alite and belite) reactions with water. Calcium carbonate formed as a result of the CO2 and Ca(OH)2 reaction may occur in the three polymorphic varieties of CaCO3 – calcite, aragonite, and vaterite. This has been proven by testing on samples taken from drilling holes made to intensify the output of rock oil through the use of CO2 (Carem et al. 2006, 2007; Scherer, Huet 2009). It is probable that the vaterite is formed in the first plate and then transforms into calcite. Aragonite is usually a transitional phase (Kurdowski 2010). The article shows the results of research on cement grouts’ phase compositions which may be applied to drilling works for the geological storage of CO2. It has been proven that different polymorphic varieties of calcium carbonate occur simultaneously in cement grouts. The grout coming into contact with leach and carbon dioxide reveals not only the presence of calcite, aragonite, and vaterite but also some phases which are the products of cement grout chloride corrosion.
Źródło:
Gospodarka Surowcami Mineralnymi; 2013, 29, 2; 79-88
0860-0953
Pojawia się w:
Gospodarka Surowcami Mineralnymi
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Masywna mineralizacja siarczkami miedzi w dolomitach z kopalni Lubin (monoklina przedsudecka)
Massive copper sulphide mineralization in dolomites from the Lubin mine (Fore-Sudetic Monocline)
Autorzy:
Król, P.
Sawłowicz, Z.
Powiązania:
https://bibliotekanauki.pl/articles/2061771.pdf
Data publikacji:
2017
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
siarczki miedzi
ruda masywna
dolomity
kalcyt
katodoluminescencja
łupek miedzionośny
copper sulphides
massive ore
dolomites
calcite
cathodoluminescence
Kupferschiefer
Opis:
Masywna mineralizacja kruszcowa występująca w dolomitach z przedsudeckiego złoża miedzi została opisana szczegółowo po raz pierwszy. W badaniach trzech profili z kopalni Lubin wykorzystano metody mikroskopii optycznej i elektronowej mikroskopii skanningowej z analizą chemiczną w mikroobszarze, katodoluminescencji oraz dyfraktometrii rentgenowskiej. Mineralizacja masywna, składająca się głównie z chalkozynu z domieszką kalcytu, występuje w skałach węglanowych (dolomitach i dedolomitach) w formie poziomej pseudożyły, podścielonej lokalnie brekcją ilasto-węglanową i łupkiem. Niżejległe dolomity uległy częściowej kalcytyzacji (dedolomityzacji). Różne generacje kalcytu szczegółowo scharakteryzowano. Zaproponowano model powstania mineralizacji masywnej. Początkowo mezotektoniczne ruchy międzywarstwowe spowodowały powstanie rozwarstwień i brekcji. Następnie proces kalcytyzacji doprowadził do dedolomityzacji oraz częściowego wypełnienia spękania. Całkowite wypełnienie spękań oraz częściowe zastąpienie w nich kalcytu oraz skał otaczających nastąpiły w wyniku działalności roztworów kruszconośnych.
Massive ore mineralization in dolomites is described for the first time from the Fore-Sudetic copper deposits. Three cross- -sections from the Lubin Mine were studied using polarized optical (PLM) and scanning electron (SEM-EDS) microscopy, also cathodoluminescence (CL) and XRD. Massive mineralization, composed mainly of chalcocite with calcite admixture, occurs in dolomites as horizontal pseudovein, locally underlain by clay-carbonate breccia and shale. Underlying dolomites were partly calcitized (dedolomitized). Various calcite generations are characterized in detail. A model of the formation of massive mineralization is proposed. Mesotectonic intralayer movements caused the cracking of dolomite layers and the formation of breccia. Calcitization led to both dedolomitization and the partial infilling of cracks. Mineralizing fluids infilled the cracks completely, partly replacing calcite and adjacent rocks.
Źródło:
Biuletyn Państwowego Instytutu Geologicznego; 2017, 468; 29--47
0867-6143
Pojawia się w:
Biuletyn Państwowego Instytutu Geologicznego
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Aglomeracja olejowa skały magnezytowej z udziałem mieszaniny jonowych surfaktantów
The oil agglomeration of magnesite rock with participation of ionic surfactants mixtures
Autorzy:
Bastrzyk, A.
Polowczyk, I.
Sadowski, Z.
Powiązania:
https://bibliotekanauki.pl/articles/1819093.pdf
Data publikacji:
2013
Wydawca:
Politechnika Koszalińska. Wydawnictwo Uczelniane
Tematy:
aglomeracja olejowa
mieszaniny jonowe
fines cleaning wastes
coal recovery
adsorption
dolomite
calcite
oleate
suspensions
flotation
mechanism
tension
Opis:
In this study, the adsorption of surfactant onto the magensite rock and the oil agglomeration of this mineral in aqueous suspension were investigated. The various concentration ratios of cationic and anionic surfactant were used. The results were evaluated by the recovery of carbonates in agglomerates. It was found that the process selectivity was highly dependent on the surfactants concentration ratio, pH, and the amount of salt added. The best separation of quartz from magnesite rock was observed at pH 9. The addition of larger quantity of sodium oleate (15.2 mg/gsolid) led to the increase of carbonates content in agglomerates up to 32.4%. However, the largest carbonates recovery was in the presence of 6.0 mg/gsolid of NaOl.
Źródło:
Rocznik Ochrona Środowiska; 2013, Tom 15, cz. 2; 1441-1459
1506-218X
Pojawia się w:
Rocznik Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synfolding calcite veins in the Holy Cross Mountains Fold Belt, central Poland
Autorzy:
Rybak-Ostrowska, B.
Konon, A.
Nejbert, K.
Kozłowski, A.
Powiązania:
https://bibliotekanauki.pl/articles/2059976.pdf
Data publikacji:
2014
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
bedding-parallel calcite veins kinematic indicators
flexural slip
Late Paleozoic buckle folding
Holy Cross Mountains Fold Belt
Opis:
Bedding-parallel calcite veins in Devonian rocks from the southern part of the Holy Cross Mountains Fold Belt in central Poland occur as tabular bodies on shallow dipping as well as vertical Late Paleozoic map-scale and mesoscopic fold limbs. The syntaxial and antitaxial bedding parallel veins contain kinematic indicators such as rotated blocks, fibre boundary steps, boudin trains, beef-like structures and congruous steps. These structures show a sense of movement consistent with the flexural slip typical of folding resulting from buckling during layer-parallel shortening. We propose the mechanism of the gradual formation of the veins and the progression of fabric development which is mostly consistent with an increasing dip angle of the fold limbs and their gradual deformation. Textures of the veins and kinematic indicators within the veins point to the syntectonic growth of calcite during the Late Paleozoic buckle folding in the Holy Cross Mountains Fold Belt.
Źródło:
Geological Quarterly; 2014, 58, 1; 99--116
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nanostructural and geochemical features of the Jurassic isocrinid columnal ossicles
Autorzy:
Stolarski, J
Gorzelak, P.
Mazur, M.
Marrocchi, Y.
Meibom, A.
Powiązania:
https://bibliotekanauki.pl/articles/22326.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
isocrinid columnal ossicle
geochemistry
Polska
Gnaszyn Dolny
ossiculum zob.ossicle
paleontology
Echinodermata
Crinoidea
Jurassic
ossicle
calcite
nanostructure
Opis:
Calcite isocrinid ossicles from the Middle Jurassic (Bathonian) clays in Gnaszyn (central Poland) show perfectly preserved micro− and nanostructural details typical of diagenetically unaltered echinoderm skeleton. Stereom pores are filled with ferroan calcite cements that sealed off the skeleton from diagenetic fluids and prevented structural and geochemical alteration. In contrast with high−Mg calcite skeleton of modern, tropical echinoderms, the fossil crinoid ossicles from Gnaszyn contain only 5.0–5.3 mole% of MgCO₃. This low Mg content can be a result of either a low temperature environment (ca. 10℃) and/or low Mg/Ca seawater ratio. Both conditions have been proposed for the Middle Jurassic marine environment. Occurrence of Mg−enriched central region of stereom bars of Jurassic columnal ossicle of Chariocrinus andreae is consistent with the concept of magnesium ions involvement in earliest growth phases of calcium carbonate biominerals.
Źródło:
Acta Palaeontologica Polonica; 2009, 54, 1; 69-75
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Badanie możliwości przygotowania past do drukowania przestrzennego (3D) z wybranych biomateriałów ceramicznych
Preliminary study on pastes of selected ceramic biomaterials for use in 3D printing
Autorzy:
Wiśniewski, Z.
Jaegermann, Z.
Tymowicz-Grzyb, P.
Biernat, M.
Pęczkowski, P.
Powiązania:
https://bibliotekanauki.pl/articles/168175.pdf
Data publikacji:
2016
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Ceramiki i Materiałów Budowlanych
Tematy:
biomateriały ceramiczne
kalcyt
aragonit
hydroksyapatyt
β-TCP
drukowanie 3D
ceramic biomaterials
calcite
aragonite
hydroxyapatite
3D printing
Opis:
Celem niniejszej pracy było przygotowanie past do drukowania przestrzennego z wybranych biomateriałów oraz wykonanie próby wyciskania past przez ustnik o średnicy wewnętrznej 0,45 mm. W ramach pracy wytypowano proszki biomateriałów i przeprowadzono badanie ich uziarnienia i morfologii. Wykonano zestawy past o różnych zawartościach substancji uplastyczniających z czterech rodzajów biomateriałów stosowanych w chirurgii kości: z kalcytu, aragonitu, hydroksyapatytu i trójfosforanu wapnia – β-TCP. Z użyciem specjalistycznej przystawki do maszyny wytrzymałościowej testowano sposób wyciskania past z jednoczesnym pomiarem siły potrzebnej do formowania pasma. Ocenę jakości uzyskanych pasm (jednorodności masy, morfologii powierzchni pasma, zdolności do wzajemnego zespolenia pasm pomiędzy sobą oraz podatności na odkształcenie) prowadzono metodą obserwacji obrazów w mikroskopie stereoskopowym i skaningowym. Następnie wytypowano receptury past, które po dopracowaniu szczegółów technologicznych będą mogły być zastosowane w docelowym urządzeniu drukującym. Doświadczenia wynikłe z realizacji pracy będą wykorzystywane przy opracowaniu receptur past i formowaniu ceramicznych struktur przestrzennych w drukarkach 3D.
The aim of this work was to prepare pastes for 3D printing made of selected biomaterials and to attempt an extrusion of pastes through the nozzle with an inside diameter of 0,45 mm. For the aim of the study powders of biomaterials were selected, their particle size was measured and powders’ morphology was observed. Pastes with different contents of plasticizing substances made of four types of biomaterials used in bone surgery: the calcite, aragonite, hydroxyapatite and tricalcium phosphate – β-TCP were prepared. The method of pastes extrusion process with simultaneous measurement of the force needed to form the bands was determined using a special adapter for testing machine. Evaluation of the quality of the bands (microstructure uniformity, surface morphology of bands, capacity to form a junction between bands and the deformability) was performed by observations in the stereomicroscope and scanning electron microscope. Then the most suitable pastes recipes were selected. Technological details of their preparation have to be optimized for their application in selected printing device. The experience resulting from this work will be used in designing ceramic pastes systems for application in 3D printers.
Źródło:
Szkło i Ceramika; 2016, R. 67, nr 4, 4; 10-15
0039-8144
Pojawia się w:
Szkło i Ceramika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Krążenie płynów w skałach okruchowych : studium przypadku piaskowców krośnieńskich z rejonu Bereżek (Bieszczady Wysokie)
Fluid circulation in clastic rocks : a case study of the Krosno sandstones from the Bereżki region (The High Bieszczady Mountains)
Autorzy:
Solecki, Marek L.
Waliczek, Marta M.
Powiązania:
https://bibliotekanauki.pl/articles/20242174.pdf
Data publikacji:
2023
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
materia organiczna
refleksyjność witrynitu
kalcyt
płaszczowina Śląska
Karpaty Zewnętrzne
organic matter
vitrinite reflectance
calcite
Silesian Nappe
Outer Carpathians
Opis:
In this study, microscopic analysis was applied to investigate fluid flow in the Oligocene shale and sandstone samples from the Krosno Beds (Silesian Nappe, Outer Carpathians) in the Bere¿ki outcrop. Analysis of calcite generation in veins and reflectance of organic matter measurements were done. Three generations of calcite were observed, indicating three stages of fluid migration along the veins in sandstones. Moreover, oil droplets and solid bitumen migration were seen during microscopic analyses. Thermal maturity based on vitrinite reflectance measurements indicates mature organic matter to hydrocarbon generation.
Źródło:
Przegląd Geologiczny; 2023, 71, 4; 227-230
0033-2151
Pojawia się w:
Przegląd Geologiczny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The economic effects of foliar fertilization of sugar beet with marine calcite
Efekty ekonomiczne dokarmiania dolistnego buraka cukrowego kalcytem morskim
Autorzy:
Litwinczuk-Bis, M.
Siuda, A.
Artyszak, A.
Powiązania:
https://bibliotekanauki.pl/articles/1790485.pdf
Data publikacji:
2019
Wydawca:
The Polish Association of Agricultural and Agribusiness Economists
Tematy:
foliar fertilization
marine calcite
profitability of production
silicon
sugar beet
kalcyt morski
krzem
dokarmianie dolistne
burak cukrowy
opłacalność produkcji
Opis:
In 2010-2012, in Sahryń (Lubelskie Voivodeship), a field experiment was carried out, the aim of which was to assess the cost-effectiveness of foliar nutrition of sugar beet with marine calcite Herbagreen Basic containing silicon. The fertilizer was applied in two variants: 1) 1 kg/ha at the 4-6 leaf stage of sugar beet (BBCH 14-16) + 2 kg/ha 21 days later; 2) 2 kg/ha at the 4-6 leaf stage of sugar beet (BBCH 14-16) + 2 kg/ha 21 days later; the effects were compared with the control (without foliar nutrition with marine calcite). Additionally, in the years 2011-2012, an identical experiment was carried out with another sugar beet cultivar. For each combination, the gross production value, foliar nutrition costs, the net production value and profitability index were calculated. The total cost of application of foliar calcite was 190 and 240 PLN/ha. The gross production value of sugar beet in experiment 1, on average over three years of research, increased in combination 1 by 24.8% and in combination 2 by 25.6% compared to the control; in experiment 2, on average for 2 years of research, in combination 1 by 15.7%, and in combination 2 by 15.0%. The increase in the net production value in experiment 1 amounted to 22.8 and 23.2% respectively, and in experiment 2 - 13.9 and 12.8%. The indicator of the profitability of foliar nutrition with marine calcite in experiment 1, on average, for the period 2010-2012, amounted to 12.6 in combination 1 and 10.3 in combination 2. In experiment 2, the index of profitability of foliar nutrition, on average, for the period 2011-2012, reached the value of 8.96 for object 1 and 6.77 for object 2.
W latach 2010-2012 w Sahryniu (woj. lubelskie) prowadzono doświadczenie, którego celem była ocena opłacalności dokarmiania dolistnego buraka cukrowego kalcytem morskim Herbagreen Basic zawierającym krzem. Nawóz stosowano w dwóch wariantach: (1) 1 kg/ha w stadium 4-6 liści buraka cukrowego (BBCH 14-16) + 2 kg/ha 21 dni później; (2) 2 kg/ha w stadium 4-6 liści buraka cukrowego (BBCH 14-16) + 2 kg/ha 21 dni później, a efekty porównywano z kontrolą (bez dokarmiania dolistnego kalcytem morskim). Dodatkowo, w latach 2011-2012 wykonano identyczne doświadczenie na innej odmianie buraka cukrowego. Dla każdej kombinacji wyliczono wartość produkcji brutto, koszty dokarmiania dolistnego, wartość produkcji netto oraz wskaźnik opłacalności. Łączne koszty aplikacji dolistnej kalcytu morskiego wynosiły 190 i 240 zł/ha. Wartość produkcji brutto buraka cukrowego w doświadczeniu 1. średnio za 3 lata badań zwiększyła się w kombinacji (1) o 24,8%, a w kombinacji (2) o 25,6% w stosunku do kontroli, a w doświadczeniu 2. średnio za 2 lata badań w kombinacji (1) o 15,7%, a w kombinacji (2) o 15,0%. Wzrost wartości produkcji netto w doświadczeniu 1. wyniósł odpowiednio 22,8 i 23,2%, a w doświadczeniu 2. – 13,9 i 12,8%. Wskaźnik opłacalności dokarmiania dolistnego kalcytem morskim w doświadczeniu 1. średnio za okres 2010-2012 wyniósł 12,6 w kombinacji 1. i 10,3 w kombinacji 2. W doświadczeniu 2. wskaźnik opłacalności dokarmiania dolistnego średnio za okres 2011-2012 osiągnął wartość 8,96 na obiekcie 1. i 6,77 na obiekcie 2.
Źródło:
Annals of The Polish Association of Agricultural and Agribusiness Economists; 2019, 21, 2; 188-195
2657-781X
2657-7828
Pojawia się w:
Annals of The Polish Association of Agricultural and Agribusiness Economists
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Calcite cements and the stratigraphical significance of the marine [delta^13]C carbonate reference curve for the Upper Cretaceous Chalk of England
Autorzy:
Jeans, C.
Hu, X.
Mortimore, R.
Powiązania:
https://bibliotekanauki.pl/articles/139078.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
cement kalcytowy
chemostratygrafia
izotopy
korelacja
kreda
krzywa referencyjna
ograniczenia
calcite cement
chemostratigraphy
correlation
Cretaceous
[delta^13]C reference curve
isotope events
limitations
Opis:
The hypothesis of Jarvis et al. (2006) that a [delta^13]C (calcite) reference curve based upon bulk samples from the Upper Cretaceous Chalk of England can be used as a primary criterion for trans-continental correlation is reviewed in the light of new stable isotope data from the Upper Albian and Cenomanian chalks of eastern England and from the Cenomanian to Campanian chalks of southern England. Evidence demonstrates that in the coloured chalks of eastern England the cements invariably have positive [delta^13]C values (up to 3.5[per mil]) except where they have been affected by hardground development when the cements have negative [delta^13]C values down to -6.5[per mil]. in contrast, the White Chalk of southern England may have cements with [delta^13]C values as negative as -8[per mil]. Modelling indicates that the coloured chalks may preserve a truer record of the primary palaeo-oceanographic [delta^13]C signal than the white and grey chalks of southern England. it is suggested that (1) many of the 72 isotope events described from the [delta^13]C (calcite) reference curve and proposed for correlation may reflect the effects of variations in the type and extent of calcite cementation; and (2) until much more is known about the patterns of calcite cementation in the Upper Cretaceous Chalk the use of minor isotope events for trans-continental stratigraphic correlation can only be applied with the utmost caution.
Źródło:
Acta Geologica Polonica; 2012, 62, 2; 173-196
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Aragonitic rostra of the Turonian belemnitid Goniacamax: arguments from diagenesis
Autorzy:
Dauphin, Y
Williams, C.T.
Barskov, I.S.
Powiązania:
https://bibliotekanauki.pl/articles/20211.pdf
Data publikacji:
2007
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Turonian
sea shell
Cephalopoda
belemnite
calcite
Goniocamax
rostrum
skeleton
sea cephalopod
diagenesis
paleoenvironment
freshwater shell
Belemnitida
aragonite
Siberia
belemnitid rostrum
Piasina River
paleontology
Opis:
The hypothesis that belemnitid rostra are formed by primary biogenic low−Mg calcite is widespread. However, the coexistence in the same rostrum of both aragonitic and calcitic components has been reported in true belemnites (Goniocamax, Turonian). A combined microstructural and chemical composition study of the comparison of shells with undisputed mineralogy from the same site as the Turonian Goniocamax, shows that these aragonitic shells display the effects of diagenetic alteration. These observations favour the hypothesis that belemnite rostra are composed of primary aragonite, rather than low−Mg calcite, and are consistent with all other cephalopod shells. Calcitic and aragonitic rostra are also known in other Dibranchiata such as Triassic Aulacocerida and Eocene Belopterina. Diagenetic changes such as shown here may clearly affect palaeo−environmental interpretations based on carbonate shells.
Źródło:
Acta Palaeontologica Polonica; 2007, 52, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Geochemical and stable isotope patterns of calcite cementation in the Upper Cretaceous Chalk, UK: Direct evidence from calcite-filled vugs in brachiopods
Autorzy:
Hu, X.
Jeans, C.
Dickson, T.
Powiązania:
https://bibliotekanauki.pl/articles/139259.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
cement kalcytowy
diageneza
historia
izotopy stabilne
kreda
pierwiastki śladowe
wpływ drobnoustrojów
anoxia
calcite cement
chalk
diagenesis
history
Microbial influence
oxia
stable isotopes
suboxia
trace elements
Opis:
The history of research into the cementation of the Upper Cretaceous Chalk of the UK is reviewed. Calcite-filled vugs within the shell cavities of terebratulid brachiopods from the Cenomanian Chalk of eastern england have been investigated by cathodoluminesence imaging, staining, electron microprobe and stable isotope analysis. This has provided the first detailed analysis of the geochemistry of the Chalk.s cement. two cement series, suboxic and anoxic, are recognized. Both start with a Mg-rich calcite with positive [delta^13]C values considered to have been precipitated under oxic conditions influenced by aerobic ammonification. The suboxic series is characterized by positive [delta^13]C values that became increasingly so as cementation progressed, reaching values of 3.5[per mil]. Manganese is the dominant trace element in the earlier cement, iron in the later cement. Mn-and Fe-reducing microbes influenced cement precipitation and the trace element and [delta^13]C patterns. The anoxic series is characterized by [delta^13]C values that became increasingly negative as cementation progressed, reaching values of .6.5[per mil]. Trace elements are dominated by iron and manganese. Sulphate-reducing microbes influenced cement precipitation and the trace element and [delta^13]C patterns. Both cement series are related closely to lithofacies and early lithification pre-dating the regional hardening of the Chalk. The suboxic series occurs in chalk which was continuously deposited and contained hematite pigment and limited organic matter. The anoxic series was associated with slow to nil deposition and hardground development inc halks that originally contained hematite pigment but no longer do so, and an enhanced supply of organic matter.
Źródło:
Acta Geologica Polonica; 2012, 62, 2; 143-172
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-62 z 62

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