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Tytuł:
Application of chromatographic plate theory on the weathered crust elution-deposited rare earth ore with carboxylate
Autorzy:
Zhang, Zhenyue
Wang, Guangshuai
Li, Chunhua
Chi, Ruan
Long, Fei
Chen, Zhuo
Chi, Xiao Wang
Liu, Defeng
Powiązania:
https://bibliotekanauki.pl/articles/1446022.pdf
Data publikacji:
2021
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
weathered crust elution-deposited rare earth ore
carboxylate ammonium
mass transfer
theory plate
rare earth
Opis:
To improve the leaching process of rare earth and reduce the impurities in the leachate, the carboxylate ammonium, such as ammonium acetate, ammonium citrate and ammonium tartrate, were selected as lixiviant to compare the effects of concentration, flow rate, pH and temperature on leaching mass process of rare earth and aluminum. Meanwhile, the leaching behaviors of rare earth and aluminum leached by three kinds of carboxylate ammonium were analyzed by chromatographic plate theory. The relationship between the flow rate and height equivalent (HETP) could fit well with the Van Deemter equation and there was an optimal flow rate (uopt) for the leaching of the rare earth and aluminum. Besides, the conditions of carboxylate ammonium lixiviant were optimized. The optimum concentrations of ammonium acetate, ammonium tartrate and ammonium citrate were 15 g/L, 25 g/L and 5 g/L respectively, the leaching flow rate was 0.50 mL/min, the pH value was approximatively 7.00 and the leaching temperature was 293 K to 303 K. At these conditions, the mass transfer efficiencies of three ammonium carboxylates for rare earth and aluminum was in the order of ammonium acetate > ammonium tartrate > ammonium citrate. Moreover, the ammonium acetate could commendably inhibit aluminum ions entering the lixivium.
Źródło:
Physicochemical Problems of Mineral Processing; 2021, 57, 4; 48-62
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bivariate distribution characteristics of spatial structure in five different Pinus massoniana forests
Autorzy:
Zhang, Ren-bo
Ding, Gui-jie
Luo, Xiao-man
Chen, Mo-fang
Powiązania:
https://bibliotekanauki.pl/articles/956829.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
uniform angle index
mingling
dominance
structure-based forest management
Opis:
Bivariate distribution is an effective approach to spatial structure analysis. Combined with two of the three structure parameters (uniform angle index (W), dominance (U) and mingling (M)), the structural bivariate characteristics of five different Pinus massoniana forests were explored in this study. Our objective was to provide a theoretical direction for structure-based and detailed management in P. massoniana forests. The bivariate traits showed that mixed artificial or secondary forests predominated by P. massoniana trees do not typically achieve the highest mingling level. Trees under extreme mingling conditions were rare and typically comprised of non-dominant species instead of dominant ones in P. massoniana forests; these trees were generally overtopped and randomly distributed. Management implications can be extracted comparing the bivariate traits between all species and dominant species. The original community structure, development stage, and mixed-tree species number affect the univariate M and, furthermore, the two bivariate U-M and W-M distributions in mixed forests. Forest type has little effect on all-species W-U traits compared to those of the dominant species. U-M traits should be adjusted first if the random frequency values are highest in W-U and W-M bivariate distribution, and it is necessary to determine whether these two bivariate traits shade the W univariate. Adjustments made based on bivariate distribution can reveal poor frequency combinations for foresters to target; this allows the simultaneous adjustment of dual aspects of forest structure based on one bivariate index. Our results show that bivariate distribution may provide very useful information for the management of P. massoniana and other forests.
Źródło:
Dendrobiology; 2017, 78; 75-84
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A novel laccase from fresh fruiting bodies of the wild medicinal mushroom Tricholoma matsutake
Autorzy:
Xu, Lijing
Zhu, Mengjuan
Chen, Xiao
Wang, Hexiang
Zhang, Guoqing
Powiązania:
https://bibliotekanauki.pl/articles/1039125.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
Tricholoma matsutake
wild mushroom
isolation
laccase
decolorization
Opis:
The knowledge about biological activities of constituents from medicinal mushrooms belonging to the genus Tricholoma is limited. A 59-kDa laccase has now been purified from fresh fruiting bodies of the mushroom Tricholoma matsutake. The purification protocol entailed ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, ion exchange chromatography on CM-cellulose, affinity chromatography on ConA-Sepharose, and gel filtration by fast protein liquid chromatography on Superdex 75. Of the various affinity and ion exchange chromatographic media employed, the laccase bound only on Con A-Sepharose. The activity of the laccase did not undergo major changes over the temperature range 20-80°C. However, all activity vanished following exposure to 100°C for 10 minutes. The enzyme activity varied only slightly over the pH range 3-5, with the optimal pH of 5, but exhibited a precipitous decline when the pH was increased to 6, and was undetectable at pH 8 and 9. The laccase showed activity in the decolorization of azo dyes without a mediator. Its N-terminal sequence demonstrated only slight resemblance to those of other mushroom laccases. The newly described laccase is distinctive from the previously isolated Tricholoma mushroom laccases in a number of aspects.
Źródło:
Acta Biochimica Polonica; 2015, 62, 1; 35-40
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characterized Microstructure and Electrical Properties of Hydrogenated Nanocrystalline Silicon Films by Raman and Electrical Conductivity Spectra
Autorzy:
Xiao-Yong, Gao
Jian-Tao, Zhao
Yu-Fen, Liu
Qing-Geng, Lin
Yong-Sheng, Chen
Jin-Hua, Gu
Shi-E, Yang
Jing-Xiao, Lu
Powiązania:
https://bibliotekanauki.pl/articles/1808127.pdf
Data publikacji:
2009-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
71.23.Cq
73.61.-r
Opis:
Microstructure and electrical properties of hydrogenated nanocrystalline silicon (nc-Si:H) film deposited on glass substrate at low temperature were characterized by average grain size, crystallinity, and dark electrical conductivity data obtained from the Raman and electrical conductivity spectroscopy, respectively. The average grain size, crystallinity and electrical conductivity have a similar change with substrate temperature. A threshold substrate temperature determined by silane concentration appears in their corresponding spectroscopy vs. substrate temperature. The dependence of crystallinity, average grain size and electrical conductivity on substrate temperature were accounted for by surface diffusion model and heterojunction quantum dot model, respectively.
Źródło:
Acta Physica Polonica A; 2009, 115, 3; 738-741
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Digital watermarking scheme based on curvelet transform and multiple chaotic maps
Autorzy:
Xiao, Yi
Xu, Ya-Chen
Zhou, Nan-Run
Lin, Zhen-Rong
Powiązania:
https://bibliotekanauki.pl/articles/27310097.pdf
Data publikacji:
2023
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
digital watermarking
curvelet transform
multiple chaotic map
Opis:
The rapid development of digital products brings security issues. Digital watermarking technology is an important means to handle these problems. To enhance the imperceptibility of watermark and locate the possible tampering as well, a digital watermarking scheme based on curvelet transform is presented by combining with multiple chaotic maps. The host image is decomposed into three parts, i.e., coarse layer, detail layer and fine layer, with curvelet transform, and a robust watermark is embedded into the coarse layer for copyright protection of digital products. In addition, an authentication watermark is embedded into the fine layer to detect and locate the illegal changes. Simulation results show that the proposed digital watermarking scheme possesses acceptable robustness and security.
Źródło:
Optica Applicata; 2023, 53, 2; 291--305
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on optimal design of vibration reduction of centrifugal air conditioning chiller based on particle damping
Autorzy:
Xiao, Wangqiang
Shi, Jinsong
Chen, Hui
Liu, Hua
Powiązania:
https://bibliotekanauki.pl/articles/2200880.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
centrifugal air-conditioning chiller
particle damping
DEM
vibration reduction
optimal scheme
Opis:
Considering vibration of centrifugal air-conditioning chillers at working conditions of 300Hz and 386Hz, a vibration reduction method for centrifugal air-conditioning chillers based on particle damping is proposed. Firstly, the vibration transfer path of the chillers is determined based on dynamic characteristics analysis of the chillers. Secondly, the vibration sensitive area of the compressor is determined by finite element analysis. Then the energy dissipation is calculated by the discrete element method (DEM) to determine the optimal installation scheme of the damper. Finally, the vibration reduction effect of the chillers after arranging the damper is verified by experiments.
Źródło:
Journal of Theoretical and Applied Mechanics; 2023, 61, 1; 189--201
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Complete Diagonalization Calculation of the Optical and EPR Data for the Tetragonal $Cu^{2+}$ Center in $Cu^{2+}$-Doped ZnSe Nanocrystals
Autorzy:
Wu, Xiao-Xuan
Zheng, Wen-Chen
Powiązania:
https://bibliotekanauki.pl/articles/1399131.pdf
Data publikacji:
2015-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
76.30.Fc
71.70.Ch
78.40.Fy
75.10.Dg
Opis:
By using the complete diagonalization (of energy matrix) method based on the cluster approach (where the admixture between the d orbitals of $d^{n}$ ion and p orbitals of ligands due to covalence effect is considered), the optical and electron paramagnetic resonance data (three optical band positions and four EPR parameters $g_{∥}$, $g_{⊥}$, $A_{∥}$, $A_{⊥}$) are calculated for the tetragonal $Cu^{2+}$ center in $Cu^{2+}$-doped poly vinyl alcohol (PVA) passivated ZnSe nanocrystals with the defect model of $Cu^{2+}$ in the interstitial octahedral site in ZnSe. The calculated results are near the experimental values. The tetragonal elongation of the $Cu^{2+}$ octahedral cluster in ZnSe nanocrystals is obtained. The results are discussed.
Źródło:
Acta Physica Polonica A; 2015, 127, 3; 795-798
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on the Optical and EPR Spectral Data and the Local Structure for the Tetragonal $Nb^{4+}$ Center in Glasses
Autorzy:
Wu, Xiao-Xuan
Yu, Xin-Peng
Zheng, Wen-Chen
Powiązania:
https://bibliotekanauki.pl/articles/1402323.pdf
Data publikacji:
2015-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
76.30.He
71.70.Ch
78.40.Pg
78.55.Qr
Opis:
Two optical bands and four EPR (or spin-Hamiltonian) parameters (g factors $g_{∥}$, $g_{⊥}$ and hyperfine structure constants $A_{∥}$, $A_{⊥}$) of the tetragonally-compressed $Nb^{4+}$ octahedral center in glasses are calculated from two methods, the complete diagonalization (of energy matrix) method and the perturbation theory method. Both methods are founded on the two-spin-orbit-parameter model where both the contribution to the spectral data from the spin-orbit parameter of central $d^{n}$ ion and that of ligand ion via covalence effect are considered. The calculated results from both the complete diagonalization (of energy matrix) method and perturbation theory method show reasonable agreement with the experimental values. The signs and possible misprint for the observed hyperfine structure constants $A_{∥}$ and $A_{⊥}$ are suggested, and the local structure of the tetragonal $Nb^{4+}$ center in glasses due to the Jahn-Teller effect is gained from the calculations. The results are discussed.
Źródło:
Acta Physica Polonica A; 2015, 128, 1; 72-75
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The separation of microscale HA in aqueous solution by foam separation technique
Autorzy:
Wenyao, Shao
Xiao, Gong
Shuming, Cui
Ying, Lin
Yinghua, Lu
Yuqing, Chen
Powiązania:
https://bibliotekanauki.pl/articles/949357.pdf
Data publikacji:
2019
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
Foam Separation
Hyaluronic Acid
Enrichment Ratio
Recovery Rate
Opis:
Hyaluronic acid (HA) has important applications in fields of health care products, cosmetics and clinical medical. However, the unique physiological properties of HA make cost of its traditional separation and extraction process relatively high. Foam separation technique has simple, gentle and efficient advantages on the separation of substances with surface activity by using bubbles as the separation medium. In this paper, natural surfactant CocamideBetaine (CAPB) was used as a foaming agent to explore the technology of microscale HA in aqueous solution by foam separation. The optimum process conditions were determined based on the recovery rate and enrichment ratio of HA by single factor and orthogonal experiment: at room temperature, pH = 7, separating air velocity (v) = 350 mL/min, HA concentration (CHA) = 50 mg/L, adding liquid volume (V) = 200 mL, collecting time (tcol) = 10 min, CAPB concentration (CCAPB) = 0.035 g/L. Under these conditions, HA enrichment ratio (E) equals 6.821 and HA recovery rate (R) equals 66.425%.
Źródło:
Polish Journal of Chemical Technology; 2019, 21, 4; 66-71
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An alternative ballistic limit equation for the Whipple shield in the shatter regime, based on characteristics of the large central fragment
Alternatywne równanie do kalkulacji balistycznych granic tarczy Whipplea w „trybie roztrzaskania”, oparte na charakterystyce dużego odłamka centralnego
Autorzy:
Wen, Ken
Di, De-ning
Chen, Xiao-wei
Powiązania:
https://bibliotekanauki.pl/articles/36440242.pdf
Data publikacji:
2021
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Lotnictwa
Tematy:
Whipple shield
debris cloud
ballistic limit equation
large central fragment
fragment identification
tarcza Whipple'a
chmura odłamków
balistyczne równanie graniczne
fragment centralny
identyfikacja fragmentów
Opis:
In the shatter regime of a Whipple shield, a large central fragment makes a significant contribution to the damage-causing capacity of the debris cloud. Herein we present a feasibleschemefor theidentification and measurement of this large central fragment and propose an alternative approach to the ballistic limit equation (BLE) for the Whipple shield, deducing an alternative ballistic limit in the shatter regime based on the large central fragment’s characteristics. This alternative BLE is compared with the phenomenological Whipple BLE, the JSC Whipple BLE and the Ryan curve. Our alternative BLE, modified at the incipient fragmentation and completed fragmentation point, is shown to agree well with experimental results.
W tzw. trybie „roztrzaskania” tarczy Whipple'a, duży centralny fragment obiektu zderzeniowego odpowiada za znaczną część ogólnej zdolności chmury odłamków do powodowania zniszczeń. W niniejszym opracowaniu przedstawiono realny schemat identyfikacji i pomiaru tego dużego centralnego fragmentu i na tej podstawie zaproponowano alternatywne podejście do balistycznego równania granicznego (BLE) dla tarczy Whipple'a. Wyznaczono alternatywną graniczną wartość balistyczną w reżimie roztrzaskania na podstawie charakterystyki centralnego fragmentu.Takie alternatywne podejście jest porównane z fenomenologicznym równaniem dla tarczy Whipple'a, z równaniem JSC Whipple oraz i z tzw. krzywą Ryana. Proponowane alternatywne równanie BLE, zmodyfikowane w punkcie początkowej i końcowej fragmentacji, wykazuje dobry poziom spójności z wynikami eksperymentalnymi.
Źródło:
Transactions on Aerospace Research; 2021, 2 (263); 12-29
0509-6669
2545-2835
Pojawia się w:
Transactions on Aerospace Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An adaptive k nearest neighbour method for imputation of missing traffic data based on two similarity metrics
Autorzy:
Wang, Yang
Xiao, Yu
Lai, Jianhui
Chen, Yanyan
Powiązania:
https://bibliotekanauki.pl/articles/949848.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
missing traffic data
similarity metrics
K-nearest neighbour method
stochastic characteristics
metoda porównywania danych
metryki podobieństwa
metoda najbliższego sąsiada
cechy stochastyczne
Opis:
Traffic flow is one of the fundamental parameters for traffic analysis and planning. With the rapid development of intelligent transportation systems, a large number of various detectors have been deployed in urban roads and, consequently, huge amount of data relating to the traffic flow are accumulatively available now. However, the traffic flow data detected through various detectors are often degraded due to the presence of a number of missing data, which can even lead to erroneous analysis and decision if no appropriate process is carried out. To remedy this issue, great research efforts have been made and subsequently various imputation techniques have been successively proposed in recent years, among which the k nearest neighbour algorithm (kNN) has received a great popularity as it is easy to implement and impute the missing data effectively. In the work presented in this paper, we firstly analyse the stochastic effect of traffic flow, to which the suffering of the kNN algorithm can be attributed. This motivates us to make an improvement, while eliminating the requirement to predefine parameters. Such a parameter-free algorithm has been realized by introducing a new similarity metric which is combined with the conventional metric so as to avoid the parameter setting, which is often determined with the requirement of adequate domain knowledge. Unlike the conventional version of the kNN algorithm, the proposed algorithm employs the multivariate linear regression model to estimate the weights for the final output, based on a set of data, which is smoothed by a Wavelet technique. A series of experiments have been performed, based on a set of traffic flow data reported from serval different countries, to examine the adaptive determination of parameters and the smoothing effect. Additional experiments have been conducted to evaluate the competent performance for the proposed algorithm by comparing to a number of widely-used imputing algorithms.
Źródło:
Archives of Transport; 2020, 54, 2; 59-73
0866-9546
2300-8830
Pojawia się w:
Archives of Transport
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Vps41, a protein involved in lysosomal trafficking, interacts with caspase-8
Autorzy:
Wang, Lu
Pan, Xiao
He, Liangqiang
Zhang, Rong
Chen, Wei
Zhang, Jing
Lu, Min
Hua, Zi-Chun
Powiązania:
https://bibliotekanauki.pl/articles/1039602.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
caspase-8
yeast two-hybrid
Vps41
protein interaction
apoptosis
Opis:
Caspase-8 is a member of the cysteine-aspartic acid protease (caspase) family which plays a central role in apoptosis and development. We screened caspase-8 interacting proteins from mouse T-cell lymphoma and 7.5-day embryo cDNA libraries by yeast two-hybrid system and obtained eleven positive clones, including Vacuolar protein sorting 41 (Vps41), a protein involved in trafficking of proteins from the late Golgi to the vacuole. The interaction of Vps41 with caspase-8 was confirmed by co-immunoprecipitation (co-IP) and co-localization studies in HEK293T cells. Co-IP experiments also showed that Vps41 binds to the p18 subunit of caspase-8 through its WD40 region and RING-finger motif. Furthermore, we found that overexpression of Vps41 promotes Fas-induced apoptosis in A549 human lung adenocarcinoma cells. The cleavage of caspase-3, a caspase-8 downstream effector, was increased when cells were transfected with Vps41-overexpressing plasmid. Together, these results suggest a novel interaction of caspase-8 with Vps41 and provide a potential role of Vps41 beyond lysosomal trafficking.
Źródło:
Acta Biochimica Polonica; 2013, 60, 1; 37-42
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Preliminary results of spatial distribution of uranium and thorium in soil profi les near a uranium industrial site, Guangdong province, China
Autorzy:
Wang, J.
Liu, J.
Chen, Y.
Song, G.
Chen, D.
Xiao, T.
Li, H.
Wang, C.
Jiang, F.
Powiązania:
https://bibliotekanauki.pl/articles/146530.pdf
Data publikacji:
2016
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
spatial distribution
thorium
uranium
U/Th ratio
Opis:
Four soil profiles were collected from locations with different distances (5, 50, 250 and 1000 m) from a uranium mill tailings dam, Guangdong province, China, to investigate the pollution status of the soil in mining/ milling-related areas based on the contents of uranium (U) and thorium (Th), thus to understand the impacts of uranium industrial activities to the surroundings. The U and Th concentrations were determined by inductively coupled plasma mass spectrometry (ICP-MS) after conventional HF-HNO3-HClO4 digestion procedures. The results indicate that the soils within 50 m from uranium tailing were severely contaminated; those in 250 and 1000 m soil samples were observed to be with local background level even though these in 250 m had slightly higher U/Th ratios. Uranium concentrations varied from 5.50 ± 0.27 to 160.55 ± 8.03 mg/kg, with maximum values recorded in an intermediate layer of the 5-m distance soil profile. In comparison, the concentration of Th ranged from 6.02 ± 0.30 to 84.71 ± 4.24 mg/kg, with maximum values observed in the top layer of the 1000-m distance soil profile. The U/Th ratio varied from 0.15 to 11.99 compared with 0.20, 0.22 and 0.26 of the average for Guangdong province, national China and the world, respectively. The mean U/Th of four soil profiles showed a reduction with distance from the uranium mill tailing dam, suggesting the relatively large magnitude of uranium elevation in soils within limited distances.
Źródło:
Nukleonika; 2016, 61, 3; 367-371
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental study of the strip coal pillar models failure with different roof and floor conditions
Autorzy:
Qu, Xiao
Chen, Shaojie
Yin, Dawei
Liu, Shiqi
Powiązania:
https://bibliotekanauki.pl/articles/2073871.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
kopalnia
filar węglowy
górnictwo odkrywkowe
“roof-strip coal pillar-floor” combined specimen
failure characteristics
acoustic emission
laboratory experiment
Opis:
In order to study the failure mechanism and characteristics for strip coal pillars, a monitoring device for strip coal pillar uniaxial compression testing was developed. Compression tests of simulated strip coal pillars with different roof and floor rock types were conducted. Test results show that, with increasing roof and floor strength, compressive strength and elastic modulus of “roof-strip coal pillar-floor” combined specimens increase gradually. Strip coal pillar sample destruction occurs gradually from edge to the interior. First macroscopic failure occurs at the edge of the middle upper portion of the specimen, and then develops towards the corner. Energy accumulation and release cause discontinuous damage in the heterogeneous coal-mass, and the lateral displacement of strip coal pillar shows step and mutation characters. The brittleness and burst tendency of strip coal pillar under hard surrounding rocks are more obvious, stress growth rate decreases, and the rapid growth acoustic emission (AE) signal period can be regarded as a precursor for instability in the strip coal pillar. The above results have certain theoretical value for understanding the failure law and long-term stability of strip coal pillars.
Źródło:
Archives of Mining Sciences; 2021, 66, 3; 475--490
0860-7001
Pojawia się w:
Archives of Mining Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study on separation of fine-particle ilmenite and mechanism using flocculation flotation with sodium oleate and polyacrylamide
Autorzy:
Peng, Yang
Xiao, Junhui
Deng, Bing
Wang, Zhen
Liu, Nengyun
Yang, Daoguang
Ding, Wei
Chen, Tao
Wu, Qiang
Powiązania:
https://bibliotekanauki.pl/articles/1450088.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
sodium oleate
polyacrylamide
synergistic effect
ilmenite
flocculation flotation
Opis:
In this paper, sodium oleate, polyacrylamide, soluble starch and sodium carboxymethyl cellulose were used as flocculants to study the flocculation and sedimentation behavior of microfine ilmenite. Sedimentation test shows that sodium oleate and polyacrylamide have good flocculation effect on ultrafine ilmenite. The flocculation rate of ilmenite can be further improved by the combination of sodium oleate and polyacrylamide. It was found that both flocculants could generate chemical adsorption with ilmenite surface, and they all react with $Fe^{3+}$ on ilmenite surface. However, sodium oleate reacts with $Fe^{3+}$ to form a water-insoluble iron oleate precipitate which coats the surface of the ilmenite and hinders the action of polyacrylamide and the remaining $Fe^{3+}$. This problem can be avoided by adding polyacrylamide followed by sodium oleate, and the flotation recovery can be increased significantly.
Źródło:
Physicochemical Problems of Mineral Processing; 2020, 56, 1; 161-172
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
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