Skocz do pozycji: 1.

Tytuł:

Electrokinetic and flotation behavior of rutile in the presence of lead ions and aluminium ions

Autorzy:

Cheng, Hongwei
Liu, Changmiao
Guo, Zhenxu
Feng, Ansheng
Wei, Min
Lv, Zihu
Wu, Dongyin
Zhao, Dengkui

Powiązania:

https://bibliotekanauki.pl/articles/110558.pdf

Data publikacji:

2019

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

lead ions
aluminium ions
rutile
flotation

Opis:

The effects of Pb(II) ions and Al(III) ions on the electro kinetic and flotation behavior of rutile were investigated by micro-flotation tests, zeta potential measurements and solution chemistry analysis. Micro-flotation results indicate that the Pb(II) ions can effectively improve the flotation recovery of rutile while the Al(III) ions significantly inhibit the flotation of rutile. Zeta potential measurements reveal that a collector styrene phosphoric acid (SPA) can adsorb on the rutile surface after the addition of Pb(II) ions, but hardly adsorb on the rutile surface after the addition of Al(III) ions. Pb(II) ions adsorb on the rutile surface in the form of Pb(OH)+ and Pb(OH)2(s), and the latter one is the main reason that activates rutile flotation. Al(III) ions adsorb on the rutile surface mainly in the form of Al(OH)3(s), which prevent the direct interaction between the rutile and the collector, resulting in a decrease of rutile flotation recovery.

Źródło:

Physicochemical Problems of Mineral Processing; 2019, 55, 2; 458-466
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 2.

Tytuł:

Application of instruments of nuclear physics to the calculation of theoretical dose distributions in various organs of the human body for beams used in hadrontherapy

Autorzy:

Maliszewska, W.
Sękowski, P.
Skwira-Chalot, I.

Powiązania:

https://bibliotekanauki.pl/articles/146972.pdf

Data publikacji:

2016

Wydawca:

Instytut Chemii i Techniki Jądrowej

Tematy:

carbon ions
hadrontherapy
hydrogen ions
SRIM
Xeloss

Opis:

The area of interests of nuclear physics are studies of reactions, wherein atomic nuclei of projectile collide with target nuclei. An amount of energy lost by projectile nucleus during its passing through the target is a major issue – it is important to know how charged particles interact with matter. It is possible to afford this knowledge by using theoretical programs that calculate energy loss applying the Bethe-Bloch equation. Hadrontherapy, which is a field of still growing interest, is based on the interactions of charged particles with matter. Therefore, there exists a need of creating a simple model that could be used to the calculation of dose distributions in biological matter. Two programs (SRIM, Xeloss), used to the calculation of energy loss by nuclear physicist, have been adapted to determine the dose distributions in analogues of human tissues. Results of the calculations with those programs for beams used in hadrontherapy (e.g. 1H, 12C) will be compared with experimental data available in references.

Źródło:

Nukleonika; 2016, 61, 1; 19-22
0029-5922
1508-5791

Pojawia się w:

Nukleonika

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 3.

Tytuł:

Influence of diaphragms on measurements of ions emitted from dense magnetized plasmas

Autorzy:

Skladnik-Sadowska, E.
Sadowski, M.

Powiązania:

https://bibliotekanauki.pl/articles/146562.pdf

Data publikacji:

2001

Wydawca:

Instytut Chemii i Techniki Jądrowej

Tematy:

diagnostic of ions
energy distribution
plasma discharges
separate ions

Opis:

The paper concerns the diagnostics of ions escaping from dense magnetized plasma (DMP) discharges. Particular attention is paid to the basic problem of the separation of such ions from the investigated plasma, under the condition that this process should not disturb the velocity (and energy) distribution functions of the measured ions.

Źródło:

Nukleonika; 2001, 46, suppl. 1; 57-60
0029-5922
1508-5791

Pojawia się w:

Nukleonika

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 4.

Tytuł:

Adsorption kinetic, equilibrium and thermodynamic investigations of Zn(II) and Ni(II) ions removal by poly(azomethinethioamide) resin with pendent chlorobenzylidine ring

Autorzy:

Kumar, P. S.
Ethiraj, H.
Venkat, A.
Deepika, N.
Nivedha, S.
Vidhyadevi, T.
Ravikumar, L.
Sivanesan, S.

Powiązania:

https://bibliotekanauki.pl/articles/780002.pdf

Data publikacji:

2015

Wydawca:

Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie

Tematy:

adsorption
models
Ni(II) ions
poly(azomethinethioamide)
Zn(II) ions

Opis:

This paper reports the application of poly(azomethinethioamide) (PATA) resin having the pendent chlorobenzylidine ring for the removal of heavy metal ions such as Zn(II) and Ni(II) ions from the aqueous solutions by adsorption technology. Kinetic, equilibrium and thermodynamic models for Zn(II) and Ni(II) ions adsorption were applied by considering the effect of contact time, initial metal ion concentration and temperature data, respectively. The adsorption influencing parameters for the maximum removal of metal ions were optimized. Adsorption kinetic results followed the pseudo-second order kinetic model based on the correlation coefficient (R2) values and closed approach of experimental and calculated equilibrium adsorption capacity values. The removal mechanism of metal ions by PATA was explained with the Boyd kinetic model, Weber and Morris intraparticle diffusion model and Shrinking Core Model (SCM). Adsorption equilibrium results followed the Freundlich model based on the R2 values and error functions. The maximum monolayer adsorption capacity of PATA for Zn(II) and Ni(II) ions removal were found to be 105.4 mg/g and 97.3 mg/g, respectively. Thermodynamic study showed the adsorption process was feasible, spontaneous, and exothermic in nature.

Źródło:

Polish Journal of Chemical Technology; 2015, 17, 3; 100-109
1509-8117
1899-4741

Pojawia się w:

Polish Journal of Chemical Technology

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 5.

Tytuł:

Investigation on different behavior and mechanism of Ca(II) and Fe(III) adsorption on spodumene surface

Autorzy:

Yu, F.
Wang, Y.
Wang, J.
Xie, Z.

Powiązania:

https://bibliotekanauki.pl/articles/110230.pdf

Data publikacji:

2014

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

spodumene surface
calcium ions
iron ions
adsorption mechanism
DFT calculation

Opis:

Behavior and mechanism of Ca2+ and Fe3+ adsorption on spodumene surface were investigated by micro flotation tests, zeta potential measurements, and density functional theory (DFT) calculation methods. The micro flotation tests showed that Ca2+ and Fe3+ activated the flotation of spodumene remarkably. However, the effect of Fe3+ was more significant than that of Ca2+. Additionally, Fe3+ significantly changed the zeta potential of spodumene while Ca2+ showed a little change. Meanwhile, the calculated adsorption energy of Fe3+ on spodumene surface was much greater than that of Ca2+ indicating that Fe3+ is more apt to be adsorbed on spodumene surface than Ca2+. The value of bond population in Ca-O illustrated that the bond of Ca-O consists of partial covalent proportion and some ionic component. On the contrary, the bond of Fe-O showed a relatively strong covalent property. The partial density of states (PDOS) of free Ca/Fe and the reacted O atom on spodumene (110) surface before and after the adsorption showed that Fe 3d orbital and O 2p orbital formed hybridization. The density of states (DOS) near the Fermi level of spodumene surface after adsorption with Fe3+ was much stronger than that with Ca2+.

Źródło:

Physicochemical Problems of Mineral Processing; 2014, 50, 2; 535-550
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 6.

Tytuł:

Study of process water effect on the activation of sphalerite during differential flotation of Pb-Cu-Zn

Autorzy:

Gutiérrez Pérez, Victor Hugo
Olvera Vázquez, Seydy Lizbeth
Santos Madrid, Rocio
Regino Piña, Rafael
Cruz Ramírez, Alejandro
Rivera Salinas, Jorge Enrique
Alaniz Hernández, Daniel Israel

Powiązania:

https://bibliotekanauki.pl/articles/2146897.pdf

Data publikacji:

2022

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

sphalerite activation
process water
differential flotation
copper ions
lead ions

Opis:

This work was aimed to analyze the effect of concentration of Cu.2+ and Pb.2+ ions in flotation process water with sphalerite activation, the analysis was performed at Cozamin Mining flotation circuit. This analysis demonstrated that (i) it was possible to determine the relationship between Sodium Cyanide and Ammonium Bisulfite used as depressants and Cu.2+ and Pb.2+ contents in the process water. (ii) It also proved the relationship between lead and iron content in the head with the Pb.2+ ions in process water. According to the data gathered and analysis performed, (iii) it was also determined that it was possible to reuse process water as long as the use of Ammonium Bisulfite was reduced and recommended replacing the use of Sodium Cyanide with Zinc Sulfate (ZnSO4) as a depressant of Sphalerite. Additionally, the concentration of Cu.2+ and Pb.2+ ions in the water should be controlled in a range of 10 to 20 ppm and 0.10 to 0.20 ppm, respectively.

Źródło:

Physicochemical Problems of Mineral Processing; 2022, 58, 3; art. no. 146906
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 7.

Tytuł:

On the nature of silver ions in complex media

Autorzy:

Loza, K.
Diendorf, J.
Sengstock, C.
Koller, M.
Epple, M.

Powiązania:

https://bibliotekanauki.pl/articles/286036.pdf

Data publikacji:

2014

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Polskie Towarzystwo Biominerałów

Tematy:

silver ions
biocides
biomaterials

Opis:

Antimicrobial biocides are commonly used to present the growth of bacteria on surfaces and within materials. They are typically added in small quantities to many applications to prevent bacterial growth on the treated object. Silver is increasingly used in many applications due to the aim to replace organic chemical agents by inorganic additives. Examples of applications are bacteriostatic water filters for household use or swimming pool algaecides and numerous devices, ranging from consumer commodities like mobile phones, refrigerators, and clothes to medical devices like catheters, implant surfaces, and plasters. To meet the diversity of application types, many different forms of silver compounds have been developed to serve this market. In particular, there is little information on the types of transformations that silver nanoparticles will undoubtedly undergo in real, complex environments during long-term aging, and the impact of these transformations on their distribution in the environment, bioavailability, and toxicity potential. The biocidal action results from the interaction of silver ions with bacteria. The most potent compounds for a high silver release are soluble silver salts like silver nitrate or silver acetate. These are fully water soluble with a high silver ion release rate. Therefore they are often used as control in cell experiments to elucidate the biological effect of silver nanoparticles. However, in the case of free silver nanoparticles the interactions can be more complex and catalytic reactions on the particle surface which depend on the size and shape of the nanoparticles can render the system very complex. If AgNO3 is used as control, it is tacitly assumed, that the free silver ion concentration is the same as that in the added AgNO3. This obviously cannot be true because of the presence of a whole set of proteins, biomolecules and inorganic ions like Cl- and H2PO4- in the biological medium. These will react with the silver ions in one or the other way. We report on experiments on the behaviour of silver ions in biologically relevant concentrations in different media, from physiological salt solution over phosphate-buffered saline solution to cell culture media. For dissolution and immersion experiments PVP-coated silver nanoparticles were synthesized by reduction with glucose in the presence of PVP. The final silver concentration in all dispersions was determined by atomic absorption spectroscopy. The dissolution of silver nanoparticles was followed in long-term experiments out of a dialysis tube which was permeable only for silver ions. In case of immersion experiments, the nanoparticles and all precipitates were isolated by ultracentrifugation, redispersed in pure water and again subjected to ultracentrifugation. The particles were analyzed by scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray powder diffraction. The dissolution requires the presence of dissolved oxygen. If no oxygen is present, only a very small fraction of silver is dissolved, possibly by traces of oxygen in the experimental setup. An oxidizing agent like H2O2 clearly enhances the dissolution. The presence of NaCl, either in pure form or as PBS, strongly slows down the dissolution, probably due to silver chloride formation. Cysteine has a clearly inhibiting effect with almost no dissolution of the silver nanoparticles whereas glucose has a decelerating effect but leads to a similar final dissolved fraction. This suggests that cysteine adsorbs onto the silver nanoparticle surface with its thiol group and prevents the oxidation. In contrast, glucose slows down the dissolution, but clearly did not prevent the oxidation on a longer time scale. We have extended the studies by mixing silver nanoparticle dispersions with different media of increasingly biological nature. The solutions/dispersions were stirred for equilibration and then subjected to ultracentrifugation. All precipitates and nanoparticles were isolated by this way and then analyzed. The results show that both initially present silver ions and released silver ions are mainly precipitated as AgCl if chloride is present. Only in the absence of chloride, glucose is able to reduce Ag+ to Ag0. The initially present silver nanoparticles were recovered in all cases. Silver phosphate was not observed in any case, probably due to the moderate pH (around 7) at which phosphate is mostly protonated to hydrogen phosphate and dihydrogen phosphate. We can conclude that released silver ions precipitate mostly as AgCl in biological media, and that most cell culture studies where silver ions are used as control are in fact studying the effect of colloidal silver chloride on the cells. To prove this assumption, human mesenchymal stem cells (hMSC) were cultured in the presence of silver chloride nanoparticles (diameter 120 nm), and the viability of the cells was analyzed by fluorescence microscopy. In general, we clearly observed that pure silver nanoparticles have lower toxicity to hMSC compared to silver chloride nanoparticles with a comparable total silver dose. Silver acetate in the biological medium had a comparable toxicity to hMSC compared to silver chloride nanoparticles with the same total silver dose.

Źródło:

Engineering of Biomaterials; 2014, 17, no. 128-129; 80
1429-7248

Pojawia się w:

Engineering of Biomaterials

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 8.

Tytuł:

Biosorption Capacity of Activated Sludge Sand Bed for Removal of Copper from Treated Wastewater

Autorzy:

Trybułowski, Łukasz
Rogowska, Weronika
Zakrzewski, Jakub

Powiązania:

https://bibliotekanauki.pl/articles/2027810.pdf

Data publikacji:

2022

Wydawca:

Polskie Towarzystwo Inżynierii Ekologicznej

Tematy:

copper ions
biosorption
wastewater

Opis:

In this paper, the biosorption capacity of activated sludge sand bed was investigated for copper removal from wastewater. A sand bed consisting of three layers was used for the study: (1) filter gravel with a diameter of 2 to 3 mm, (2) a biological part inoculated with 200 ml of flocculent activated sludge with a dry weight of 5 kg/$m^3$, (3) filter sand with a grain diameter of about 3 mm. The filter was fed with model wastewater prepared with sodium acetate, potassium nitrate, ammonium chloride, and potassium dihydrogen phosphate I and II basic. The source of Cu ions in the wastewater was $CuSO_4$. The model wastewater used in this study was collected every 24 hours. The experiment was terminated when the concentration of Cu in the treated wastewater sample was equal to that in the treated wastewater. Such a phenomenon was indicative of the depletion of the sorption capacity of the tested bed, which was observed after 26 days. The concentration of copper in raw and effluent from the bed was studied using atomic absorption spectroscopy (ASA) in samples mineralized in nitric acid ($HNO_3$) with the addition of perhydrol ($H_2O_2$). Two equilibrium models, Langmuir and Freudlich, were analyzed to study the absorption isotherms.

Źródło:

Journal of Ecological Engineering; 2022, 23, 2; 61-69
2299-8993

Pojawia się w:

Journal of Ecological Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 9.

Tytuł:

A Superconducting Cyclotron as a primary accelerator for exotic beam facilities

Autorzy:

Maggiore, M.
Rifuggiato, D.
Calabretta, L.

Powiązania:

https://bibliotekanauki.pl/articles/146203.pdf

Data publikacji:

2003

Wydawca:

Instytut Chemii i Techniki Jądrowej

Tematy:

cyclotron
ions
medical
superconducting

Opis:

A four sector compact superconducting cyclotron for light ion beams with a maximum energy of 250 MeV/amu has been studied. This cyclotron is mainly designed to accelerate H2 + ions to be extracted by stripping. Ions like C, O or Ne can also be accelerated and extracted by stripping. Extraction by stripping allows to overcome many problems, especially if a certain beam intensity is requested. The preliminary design model of the magnet circuit has been accomplished with the 3D electromagnetic code OPERA [4]. The design of the main coils and of the cryostat has been investigated, too. The features of beam dynamics of this cyclotron, including extraction trajectories, will be presented. Several fields of application have been envisaged for this cyclotron, namely nuclear physics, therapy treatment, interdisciplinary research and radioisotope production using low or medium intensity beams.

Źródło:

Nukleonika; 2003, 48,suppl.2; 165-167
0029-5922
1508-5791

Pojawia się w:

Nukleonika

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 10.

Tytuł:

Various ionic substitutions in hydroxyapatites - physicochemical studies

Autorzy:

Kolmas, J.
Laskus, A.
Szurkowska, K.
Pajor, K.
Pajchel, Ł.

Powiązania:

https://bibliotekanauki.pl/articles/285828.pdf

Data publikacji:

2018

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Polskie Towarzystwo Biominerałów

Tematy:

hydroxyapatite
ions
physicochemical analysis

Źródło:

Engineering of Biomaterials; 2018, 21, 148; 45
1429-7248

Pojawia się w:

Engineering of Biomaterials

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 11.

Tytuł:

Environmentally and Economically Feasibility Manufacturing Process of Potassium Nitrate for Small Scale Industries: A Review

Autorzy:

Joshi, C. S.
Shukla, M. R.
Patel, K.
Joshi, J. S.
Sahu, O.

Powiązania:

https://bibliotekanauki.pl/articles/411997.pdf

Data publikacji:

2015

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

Chemical
discharge
ions
Salts
Waste

Opis:

Potassium Nitrate (PN) is of the basic need of chemical industry. With increase of demand in different production section of fertilizer, pharmaceutical, explosive, food industry etc, potassium nitrate the production becoming non economical to industry. The operating conditions and parameters are the main factors, which responsible for maximised the profits. The main aim of this study is to compared the production potassium nitrate in profitable as well as environmentally suitability way. From the literature different manufacturing process has been summarized for concluding this study.

Źródło:

International Letters of Chemistry, Physics and Astronomy; 2015, 41; 88-99
2299-3843

Pojawia się w:

International Letters of Chemistry, Physics and Astronomy

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 12.

Tytuł:

Application of polymer inclusion membranes doped with 1-hexyl-4-methylimidazole for pertraction of zinc(II) and other transition metal ions

Autorzy:

Ulewicz, M.
Radzyminska-Lenarcik, E.

Powiązania:

https://bibliotekanauki.pl/articles/110567.pdf

Data publikacji:

2015

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

polymer inclusion membrane
PIM
metal ions separation
zinc(II)
transition metal ions
imidazole derivatives

Opis:

Transport of Zn(II) from unary aqueous chloride solutions and from solutions which contain mixtures of Cd(II), Co(II) and Ni(II) ions in source phases (cMe = 0.001 mol/dm3, pH = 6.0) across polymer inclusion membranes (PIMs) doped with 1-hexyl-4-methylimidazole as ion carrier was studied. The use of 1-hexyl-4-methylimidazole enables the separation of 98.5% Zn(II) from a unary solution and 96.9% from a quaternary solution of Zn(II)-Cd(II)-Co(II)-Ni(II) after running the process for 24 hours. Using that ion carrier, the metals are transported in the following order: Zn(II) > Cd(II) > Ni(II) > Co(II), and the selectivity coefficients of Zn(II)/Cd(II), Zn(II)/Ni(II), and Zn(II)/Co(II) are 12.9, 23.4 and 40.8, respectively. Findings of atomic force microscopy (AFM) examinations as well as thermograms of a polymer inclusion membrane containing 1-hexyl-4-methylimidazole are also presented. A membrane with 1.0 mol/dm3 of carrier has a porosity of 15.8%, and roughness of 6.6 nm. The membranes remain thermally stable at temperatures up to 200oC. The findings were compared with earlier-reported results for 1-hexylimidazole.

Źródło:

Physicochemical Problems of Mineral Processing; 2015, 51, 2; 447-460
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 13.

Tytuł:

Germanate glasses co-doped with Ce3+/Ln3+ (Ln = Pr, Tb, Dy) for white light emitting diodes

Autorzy:

Górny, Agata
Sołtys, Marta
Pisarska, Joanna
Pisarski, Wojciech A.

Powiązania:

https://bibliotekanauki.pl/articles/173993.pdf

Data publikacji:

2019

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

glasses
rare earth ions
white luminescence

Opis:

Glasses doped with lanthanides ions may be good white light emitters due to their interesting physical and spectroscopic properties. In this paper, the optical spectroscopy of rare earths doped glasses with a special emphasis on application as white LED were presented. The luminescent glass materials containing Ln³⁺ (Ln = Pr, Tb, Dy) and Ce³⁺ ions were obtained. The glasses samples were prepared by a traditional melt-quenching technique. The optical properties of glasses containing various concentrations of rare earth ions were analyzed. It was observed that luminescence bands corresponding to characteristic transitions of Ln³⁺ and cerium ions are present on spectra measured under direct excitation of Ce³⁺. Therefore, it indicates that the energy transfer process between Ce³⁺ /Pr³⁺, Ce³⁺ /Tb³⁺, Ce³⁺ / Dy³⁺ ions in glasses occurs. Some parameters such as correlated color temperature (CCT) and chromaticity coordinates (CIE) that characterize white LEDs were analyzed and discussed in detail.

Źródło:

Optica Applicata; 2019, 49, 3; 383-391
0078-5466
1899-7015

Pojawia się w:

Optica Applicata

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 14.

Tytuł:

Analiza struktury chemicznej hydroksyapatytu wzbogaconego jonami Mn 2+ wygrzewanego w wysokiej temperaturze
Structural characterization of thermally processed hydroxyapatite enriched in Mn2+ ions

Autorzy:

Kolmas, J.
Jabłoński, M.
Ślósarczyk, A.
Kołodziejski, W.

Powiązania:

https://bibliotekanauki.pl/articles/286145.pdf

Data publikacji:

2014

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Polskie Towarzystwo Biominerałów

Tematy:

hydroksyapatyty
biokompatybilność
apatyt
hydroxyapatite
biocompatibility
ions

Opis:

Syntetyczne hydroksyapatyty (HAs), ze względu na wysoką biokompatybilność z ludzkimi tkankami zmineralizowanymi, są szeroko stosowane jako biomateriały w ortopedii oraz stomatologii. Struktura hydroksyapatytu Ca10(PO4)6(OH)2 pozwala na szereg jonowych podstawień, które mogą zachodzić zarówno w pozycji kationów wapnia jak i ortofosforanów oraz strukturalnych grup hydroksylowych. Wprowadzenie dodatkowych jonów do struktury hydroksyapatytu może wpływać na jego właściwości biologiczne i fizykochemiczne. Mangan jest śladowym pierwiastkiem wchodzącym w skład biologicznego apatytu (mineralnego składnika kości oraz zębów). Odgrywa on kluczową rolę w powstawaniu matrycy organicznej. Dodatkowo indukuje integryny, grupę receptorów umożliwiających adhezję komórek. Ostatnio przeprowadzone badania potwierdziły, że hydroksyapatyt wzbogacony jonami manganu Mn2+ wykazuje łatwiejszą osteointegrację niż czysty hydroksyapatyt, dlatego też może być z powodzeniem stosowany jako pokrycie implantów metalicznych. W powyższej pracy wykorzystano standardową metodę mokrą do syntezy hydroksyapatytów zawierających niewielkie ilości jonów Mn2+. Otrzymane próbki wygrzewano następnie w dwóch różnych temperaturach: 800 oraz 1250°C. Głównym celem tej pracy było zbadanie wpływu procesu termicznego na strukturę chemiczną hydroksyapatytuwzbogaconego jonami manganowymi. Do badań fizykochemicznych wykorzystano: proszkową dyfraktometrię rentgenowską (PXRD), mikroskopię elektronową (SEM oraz TEM), spektroskopię w podczerwieni (FT-IR) oraz spektroskopię magnetycznego rezonansu jądrowego w ciele stałym (ssNMR). Wprowadzenie jonów Mn2+ do struktury hydroksyapatytu zostało potwierdzone dzięki zastosowaniu metod PXRD oraz ssNMR. Wykazano także, że obecność manganu ułatwia termiczny rozkład hydroksyapatytu do oksyhydroksyapatytu. Próbki wygrzewane w wyższej temperaturze (1250°) okazały się niehomogeniczne. Zawierały, oprócz fazy hydroksyapatytu, dodatkowe fazy krystaliczne: oksyhydroksyapatyt, oksyapatyt, dziewięciotlenek dwufosforu i czterowapnia (TTCP) oraz α-ortofosforan wapnia (αTCP). Użyte metody fizykochemiczne pozwoliły stwierdzić, że w próbkach kalcynowanych (wygrzewanych w temperaturze 800°C) jony manganowe zajmują przede wszystkim pozycje wapnia Ca(I) w komórce elementarnej hydroksyapatytu. Podczas wygrzewania w wyższej temperaturze dochodzi do częściowego przemieszczenia jonów manganu w pozycje Ca(II).
Synthetic hydroxyapatites (HAs), due to their high compatibility with human mineralized tissues are widely used in implant materials for orthopaedic and dental applications. Hydroxyapatite structure Ca10(PO4)6(OH)2 is tolerant to several ionic substitutions. They can occur in HA for calcium cations, for orthophosphates and structural hydroxyl ions. The incorporation of additional ions into the apatite crystals may change their biological or physicochemical properties. Manganese appears in biological apatite (bone and teeth) and plays a key role in the development of organic matrix. It also induces integrins, receptors mediating cellular interactions with extracellular matrix and cell surface ligands. Manganese-doped HA exhibits better osseointegration than pure HA, thus it may be used as a coating of metallic implants. In this paper, hydroxyapatites enriched in small amounts of manganese ions Mn2+ were synthesized by standard wet method. The obtained samples were heated at two different temperatures: 800 and 1250ºC. The main aim of this study was to determine the influence of thermal processing of hydroxyapatite enriched in Mn2+ ions on its chemical structure. For profound physicochemical studies powder X-ray diffractometry (PXRD), electron microscopy (SEM and TEM), infrared spectroscopy (FT-IR) and solid-state nuclear magnetic resonance (ssNMR) were applied. The incorporation of manganese ions was confirmed using PXRD and ssNMR methods. It was found that the presence of manganese facilitates hydroxyapatite dehydration and decomposition to oxyhydroxyapatite. The samples heated at 1250ºC are not homogenous and contain, apart from hydroxyapatite other crystalline phases: oxyhydroxyapatite, oxyapatite, tetracalcium phosphate (TTCP) and α-tricalcium phosphate (αTCP). In the calcined sample (heated at 800ºC), manganese ions preferentially occupy the Ca(I) position in the hydroxyapatite crystallographic unit cell. During heat treatment at the higher temperature, some Mn2+ ions move to the Ca(II) position.

Źródło:

Engineering of Biomaterials; 2014, 17, no. 128-129; 10-11
1429-7248

Pojawia się w:

Engineering of Biomaterials

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 15.

Tytuł:

Reduction of chromium(VI) ions from aqueous solutions by using the solvent impregnated resin

Autorzy:

Wójcik, G.
Hubicki, Z.

Powiązania:

https://bibliotekanauki.pl/articles/115625.pdf

Data publikacji:

2011

Wydawca:

Fundacja na Rzecz Młodych Naukowców

Tematy:

sorption of chromium(VI) ions
reduction

Opis:

The solvent impregnated resins enables effective recovery of microquantities of chromium(VI) ions from wastewaters. The solvent impregnated resin (SIR) Amberlite XAD 7 HP as polymer matrix has been prepared by the wet-impregnation technique. Aliquat 336 was employed as the extractant and acetone as the solvents for impregnation. Sorption of chromium(VI) was investigated in the batch process . Sorption of chromium(VI) was studied in the pH range from 1.5 to 7. It was stated that sorption of chromium(VI) ions depends on acidity of solution. The values of recovery factors of chromium(VI) are higher at low pH than in neutral solution. The speciation of chromium was investigated in the studied pH range. Reduction of chromium(VI) to chromium(III) under acidic conditions was observed. Chromium was determined by using the spectrophotometric and atomic absorption spectroscopy methods. Both methods permit to observe changing of valence of chromium(III) and (VI) oxidation states. The prepared SIR is a new sorbent used for recovery of chromium ions from wastewaters.

Źródło:

Challenges of Modern Technology; 2011, 2, 3; 41-43
2082-2863
2353-4419

Pojawia się w:

Challenges of Modern Technology

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 16.

Tytuł:

Production of negative hydrogen ions using a low-pressure reflex discharge source

Autorzy:

Toader, E.

Powiązania:

https://bibliotekanauki.pl/articles/147442.pdf

Data publikacji:

2006

Wydawca:

Instytut Chemii i Techniki Jądrowej

Tematy:

magnetized plasma
negative ions
plasma sources

Opis:

In this paper we analyze the possibility to use the reflex discharge plasma as a volume source of negative hydrogen ions. The basic internal parameters like the temperature Te and the density ne of the electrons, the density ni of the positive hydrogen ions, the density n- of the negative hydrogen ions, and the negative ion fraction n-/ne are measured and discussed. The operating conditions are optimized within the pressure range 0.1-10 Pa, the discharge power 20-140 watt, and the magnetic field 0-150 gauss. The experiment shows that the enhanced magnetic ionization is the most effective within the pressure range from 0.7 to 4.0 Pa. When p ť 1 Pa the cold electron temperature Te is 0.77 eV, the cold electron density ne is 4.2 ´ 10 18 m-3 and the negative ion density n- is as high as 0.8 x 10 17 m-3. The negative ion fraction n-/ne increases from 1.4% for p = 0.1 Pa to almost 2.2% within the pressure range 1-4 Pa. The positive ion density scales with the power, while the negative ion density and the negative ion fraction seems to saturate at higher power levels.

Źródło:

Nukleonika; 2006, 51, 1; 29-35
0029-5922
1508-5791

Pojawia się w:

Nukleonika

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 17.

Tytuł:

Supramolecular complexes of cobalt(II), manganese(II) and cadmium(II) with bis(terpyridine) ligand as novel luminescent materials

Autorzy:

Wałęsa-Chorab, M.
Gorczyński, A.
Marcinkowski, D.
Hnatejko, Z.
Patroniak, V.

Powiązania:

https://bibliotekanauki.pl/articles/779935.pdf

Data publikacji:

2013

Wydawca:

Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie

Tematy:

luminescence
supramolecular complexes
transition metal ions

Opis:

Self-assembly of N6-donor bis(terpyridine) ligand L with transition metal ions: Co(II), Mn(II) and Cd(II) leads to a formation of three kinds of supramolecular complexes. In the electronic absorption and emission spectra of supramolecular complexes additional bands were observed what was ascribed to the coordination of ligand molecules to metal ions. Luminescence properties of these complexes strongly depend on the kind of metal ions and counter ions. The effective blue luminescence was observed in the case of Mn(II) and Cd(II) complexes in which all N-donor atoms of ligand molecules coordinate with the metal center.

Źródło:

Polish Journal of Chemical Technology; 2013, 15, 3; 91-95
1509-8117
1899-4741

Pojawia się w:

Polish Journal of Chemical Technology

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 18.

Tytuł:

Metody usuwania jonów kadmu i ołowiu z roztworów wodnych
Methods of cadmium and lead ions removal from aqueous solutions

Autorzy:

Kasprzyk, P.
Sanak-Rydlewska, S.

Powiązania:

https://bibliotekanauki.pl/articles/394659.pdf

Data publikacji:

2016

Wydawca:

Polska Akademia Nauk. Instytut Gospodarki Surowcami Mineralnymi i Energią PAN

Tematy:

wymiana jonowa
jony kadmu
jony ołowiu
Purolite C160
ion exchange process
cadmium ions
lead ions

Opis:

W pracy zostaną przedstawione metody eliminacji jonów kadmu i ołowiu z roztworów wodnych. Wśród nich wymiana jonowa staje się coraz popularniejszą metodą usuwania zanieczyszczeń ze ścieków przemysłowych. Za tą metodą przemawiają: prostota procesu, niska energochłonność oraz możliwość selektywnego rozdziału zanieczyszczeń. Wymieniacz jonowy używany w procesie można wielokrotnie stosować, bowiem można go poddawać regeneracji. Stosowanie kolumn jonowymiennych umożliwia także budowę modułową linii technologicznej oczyszczania ścieków oraz szybką wymianę modułów według potrzeb technologicznych i składu ścieków. Wymianę jonową można rozpatrywać jako proces membranowy, gdzie membraną jest powierzchnia ziarna – będąca selektywnie przepuszczalną dla wymienianych jonów. W artykule przedstawiono badania laboratoryjne dotyczące wpływu wybranych parametrów procesu na wydajność wymiany jonowej dla jonów kadmu i ołowiu. Pierwiastki te według polskiego prawodawstwa uznane są za substancje szczególnie szkodliwe i mają działanie kancero- i mutagenne. Najwyższa koncentracja tych pierwiastków występuje na terenach uprzemysłowionych oraz na terenach miejskich. Mogą one pochodzić z przemysłu metalurgicznego, produkcji baterii i akumulatorów, ze spalania paliw kopalnych lub produkcji tworzyw sztucznych. Emisja kadmu i ołowiu do środowiska wodnego odbywa się poprzez odprowadzanie wód kopalnianych czy ścieków z przemysłu hydrometalurgicznego lub z galwanizerni. Badania własne wskazują, że eliminacja jonów Pb i Cd najkorzystniej zachodzi w roztworach o pH około 4 i utrzymuje się na wysokim poziomie w zakresie kwaśnego środowiska. Jonit Purolite C-160 umożliwia osiągnięcie współczynnika wydzielania (X) około 99% dla kadmu – tabela 1, natomiast współczynnik ten dla jonów ołowiu nie przekracza 97% – tabela 2.
This article presents the methods of cadmium and lead ions removal from aqueous solutions. The ion exchange method is becoming a more and more popular method of removing impurities from wastewater. The main advantages of this method are: process simplicity, low energy consumption and the possibility of the selective separation of pollutants. The ion exchanger used in the process could be regenerated, therefore, it could be used repeatedly. The use of ion-exchange columns also allows for the modular construction of the process line and the rapid replacement of modules according to the technological needs and composition of the wastewater. Ion exchange can be seen as a membrane process in which the grain surface acts as a membrane – which is selectively permeable to the exchanged ions. The article presents laboratory studies on the influence of the ion exchange process parameters on the efficiency of cadmium and lead ion exchange. These elements are suspected of carcinogenicity and teratogenicity, and according to Polish Legislation, are considered to be harmful substances. The highest concentration of these elements occurs in industrialized areas and in urban areas. They may come from the hydrometallurgical industry, the production of batteries and accumulators from the burning of fossil fuels and the production of plastics. The emission of cadmium and lead into the aquatic environment is done through the discharge the mine water and wastewater from the hydrometallurgical industry and from electroplating. Experiments show that the elimination of Pb and Cd ions preferably occurs in aqueous solutions with a pH around 4. Ion exchange resin Purolite C-160 allows a removal coefficient (X) in the range of about 99% for cadmium to be achieved – Table 5.1, while the same coefficient for lead ions does not exceed 97% – Table 5.2.

Źródło:

Zeszyty Naukowe Instytutu Gospodarki Surowcami Mineralnymi i Energią PAN; 2016, 94; 205-215
2080-0819

Pojawia się w:

Zeszyty Naukowe Instytutu Gospodarki Surowcami Mineralnymi i Energią PAN

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 19.

Tytuł:

Generation of ·OH initiated by interaction of Fe2+ and Cu+ with dioxygen; comparison with the Fenton chemistry.

Autorzy:

Urbański, Norbert
Beręsewicz, Andrzej

Powiązania:

https://bibliotekanauki.pl/articles/1044216.pdf

Data publikacji:

2000

Wydawca:

Polskie Towarzystwo Biochemiczne

Tematy:

superoxide dismutase
autoxidation
catalase
free radical
Fenton reaction
hydroxyl radical
iron ions
copper ions
desferrioxamine

Opis:

Iron and copper toxicity has been presumed to involve the formation of hydroxyl radical (·OH) from H2O2 in the Fenton reaction. The aim of this study was to verify that Fe2+-O2 and Cu+-O2 chemistry is capable of generating ·OH in the quasi physiological environment of Krebs-Henseleit buffer (KH), and to compare the ability of the Fe2+-O2 system and of the Fenton system (Fe2+ + H2O2) to produce ·OH. The addition of Fe2+ and Cu+ (0-20 μM) to KH resulted in a concentration-dependent increase in ·OH formation, as measured by the salicylate method. While Fe3+ and Cu2+ (0-20 μM) did not result in ·OH formation, these ions mediated significant ·OH production in the presence of a number of reducing agents. The ·OH yield from the reaction mediated by Fe2+ was increased by exogenous Fe3+ and Cu2+ and was prevented by the deoxygenation of the buffer and reduced by superoxide dismutase, catalase, and desferrioxamine. Addition of 1 μM, 5 μM or 10 μM Fe2+ to a range of H2O2 concentrations (the Fenton system) resulted in a H2O2-concentration-dependent rise in ·OH formation. For each Fe2+ concentration tested, the ·OH yield doubled when the ratio [H2O2]:[Fe2+] was raised from zero to one. In conclusion: (i) Fe2+-O2 and Cu+-O2 chemistry is capable of promoting ·OH generation in the environment of oxygenated KH, in the absence of pre-existing superoxide and/or H2O2, and possibly through a mechanism initiated by the metal autoxidation; (ii) The process is enhanced by contaminating Fe3+ and Cu2+; (iii) In the presence of reducing agents also Fe3+ and Cu2+ promote the ·OH formation; (iv) Depending on the actual [H2O2]:[Fe2+] ratio, the efficiency of the Fe2+-O2 chemistry to generate ·OH is greater than or, at best, equal to that of the Fe2+-driven Fenton reaction.

Źródło:

Acta Biochimica Polonica; 2000, 47, 4; 951-962
0001-527X

Pojawia się w:

Acta Biochimica Polonica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 20.

Tytuł:

Bioaccumulation of uranium from waste water using different strains of Saccharomyces cerevisiae

Autorzy:

Tykva, R.
Novák, J.
Podracká, E.
Popa, K.

Powiązania:

https://bibliotekanauki.pl/articles/148088.pdf

Data publikacji:

2009

Wydawca:

Instytut Chemii i Techniki Jądrowej

Tematy:

bioaccumulation
uranium
Saccharomyces cerevisiae
competitive ions

Opis:

Five different strains of Saccharomyces cerevisiae were tested for their abilities to accumulate uranium from waste water containing competitive ions. Samples of water passing out from a previous uranium mill were used. The strains tested possess different abilities to accumulate uranium. The kinetics of bioaccumulation, the leaching degree, the influence of cell density and their origin were investigated. Under the applied experimental conditions, more than a half of the total activity (uranium and the decay products) could be accumulated after 60 min contact time of 1 mL S. cerevisiae suspension and 5 mL of water. The other cations present in solution effectively competed for the uranium accumulation. 226Ra and its decay products were completely retained using all tested strains.

Źródło:

Nukleonika; 2009, 54, 2; 143-148
0029-5922
1508-5791

Pojawia się w:

Nukleonika

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 21.

Tytuł:

Electron capture negative ion mass spectra of some freon derivatives

Autorzy:

Asfandiarov, N.
Pshenichnyuk, S.
Fal’ko, V.
Wnorowska, J.
Wnorowski, K.
Szamrej-Foryś, I.

Powiązania:

https://bibliotekanauki.pl/articles/148517.pdf

Data publikacji:

2003

Wydawca:

Instytut Chemii i Techniki Jądrowej

Tematy:

negative ions
electron capture
freon derivatives

Opis:

The temperature dependence of dissociative attachment has been investigated in the temperature range 350-575 K for two freon derivatives 1,1,1-C2H3F2Cl and C2F5Cl using Electron Capture Negative Ion Mass Spectra (ECNI MS). The temperature dependence for 1,1,1-C2H3F2Cl is similar to that observed in the case of CF3Cl reported by Illenberger et al. In contrast, C2F5Cl exhibits quite a different spectrum and its temperature behavior. It has been suggested that sigma*C-Cl delocalization onto two empty orbital leads to Cl- ion formation in two different resonance states.

Źródło:

Nukleonika; 2003, 48, 2; 83-88
0029-5922
1508-5791

Pojawia się w:

Nukleonika

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 22.

Tytuł:

Determination of the effective diffusivity of cadmium(II) in calcium alginate beads

Autorzy:

Kwiatkowska-Marks, S.
Wójcik, M.
Kopiński, L.

Powiązania:

https://bibliotekanauki.pl/articles/347047.pdf

Data publikacji:

2011

Wydawca:

Politechnika Bydgoska im. Jana i Jędrzeja Śniadeckich. Wydział Technologii i Inżynierii Chemicznej

Tematy:

cadmium ions
alginate beads
effective diffusivity

Opis:

Effective diffusivity (De) of cadmium compounds was calculated in the beads. The study was carried out using two methods: a shrinking core model (SCM) method and a newly developed method named conductometric. It turned out to be a simple and effective method for the calculation of effective diffusivity of Cd(II) in alginate sorbents. The De values obtained by the two methods depended on the alginate content in the beads. However, SCM, in contrast to the conductometric method, gave De values increasing with increasing alginate levels in the beads and lower than the molecular diffusivity of Cd(II), this being inconsistent with the mechanism of diffusion in porous carriers. Hence, the conductometric method can be considered as one giving more reliable results, compared with the SCM method. Moreover, diffusion retardation coefficients for the alginate beads were calculated. Enhanced content of the biopolymer in the beads caused retardation of Cd(II) diffusion in the beads due to the decreasing calculated retardation coefficients with the increasing alginate contents in the beads.

Źródło:

Ars Separatoria Acta; 2011, 8; 11-23
1731-6340

Pojawia się w:

Ars Separatoria Acta

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 23.

Tytuł:

Effect of divalent metal ions on annexin-mediated aggregation of asolectin liposomes.

Autorzy:

Mel'gunov, Vladimir
Akimova, Elena
Krasavchenko, Kirill

Powiązania:

https://bibliotekanauki.pl/articles/1044309.pdf

Data publikacji:

2000

Wydawca:

Polskie Towarzystwo Biochemiczne

Tematy:

aggregation
liposome
annexin
divalent metal ions

Opis:

Annexins belong to a family of Ca2+- and phospholipid-binding proteins that can mediate the aggregation of granules and vesicles in the presence of Ca2+. We have studied the effects of different divalent metal ions on annexin-mediated aggregation of liposomes using annexins isolated from rabbit liver and large unilamellar vesicles prepared from soybean asolectin II-S. In the course of these studies, we have found that annexin-mediated aggregation of liposomes can be driven by various earth and transition metal ions other than Ca2+. The ability of metal ions to induce annexin-mediated aggregation decreases in the order: Cd2+>Ba2+, Sr2+>Ca2+>>Mn2+>Ni2+>>Co2+. Annexin-mediated aggregation of vesicles is more selective to metal ions than the binding of annexins to membranes. We speculate that not every type of divalent metal ion can induce conformational change sufficient to promote the interaction of annexins either with two opposing membranes or with opposing protein molecules. Relative concentration ratios of metal ions in the intimate environment may be crucial for the functioning of annexins within specialized tissues and after treatment with toxic metal ions.

Źródło:

Acta Biochimica Polonica; 2000, 47, 3; 675-683
0001-527X

Pojawia się w:

Acta Biochimica Polonica

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 24.

Tytuł:

Non-destructive viscometric studies of enzymic milk coagulation III. The effect of pH, temperature and Ca-ions concentration on the secondary phase of milk coagulation
Nie niszczące badania wiskozymetryczne enzymatycznego procesu krzepnięcia mleka III. Wpływ stężenia jonów wapniowych, pH i temperatury na wtórną fazę enzymatycznego krzepnięcia mleka

Autorzy:

Bachman, S.
Klimczak, B.
Gasyna, Z.

Powiązania:

https://bibliotekanauki.pl/articles/1398347.pdf

Data publikacji:

1980

Wydawca:

Instytut Rozrodu Zwierząt i Badań Żywności Polskiej Akademii Nauk w Olsztynie

Tematy:

milk coagulation
immobilized rennin
Ca-ions

Opis:

It was observed that within the pH range between 5.57 and 6.37 the time of development of the secondary phase of the rennet milk coagulation is independent from temperatures between 25° and 35°C. Increased concentration of Ca-ions between 0.66 and 1.1 mg CaCl₂ /ml milk accelerates the formation of the secondary phase.
Kontynuując wcześniej prowadzone prace na temat enzymatycznego procesu krzepnięcia mleka [l, 2] w tej części przedstawiono badania wpływu pH oraz stężenia jonów wapniowych we współdziałaniu z temperaturą na wtórną fazę enzymatycznego krzepnięcia mleka. Do badań zastosowano unieruchomioną renninę. Stwierdzono, że dla wartości pH od 5,57 do 6,37 czas wystąpienia fazy wtórnej jest niezależny od temperatury w zakresie 25-35°C. W miarę zwiększenia wartości pH następował spadek szybkości zmiany lepkości mleka w okresie wtórnej fazy. Wyznaczono zależność stałej szybkości zmian lepkości od stężenia jonów wodorowych: k = k'(H+)0,5. Określono zależność odwrotności czasu wystąpienia fazy wtórnej od stężenia jonów wapniowych w granicach 0,66-1,1 mg CaCl₂ /ml mleka dla temperatur w zakresie 25-35°C. Stwierdzono przyspieszenie wystąpienia fazy wtórnej w miarę wzrostu stężenia jonów wapniowych w mleku.

Źródło:

Acta Alimentaria Polonica; 1980, 06, 3; 135-143
0137-1495

Pojawia się w:

Acta Alimentaria Polonica

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 25.

Tytuł:

The mechanical aspect of titanium ion release after posterior instrumentation for early onset scoliosis

Autorzy:

Danielewicz, Anna
Fatyga, Marek
Wójciak-Kosior, Magdalena
Sawicki, Jan
Różańska-Boczula, Monika
Sowa, Ireneusz
Latalski, Michał

Powiązania:

https://bibliotekanauki.pl/articles/109528.pdf

Data publikacji:

2019

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

scoliosis
metal ions
implant
titanium
mineralization

Opis:

Surgical treatment of early onset scoliosis (EOS) is connected with the risk of early and late complications. The aim of the study is to assess influence of the rod fracture on the titanium ion release (TIR) in traditional growing rods instrumentation for EOS.56 patients treated surgically due to EOS were divided into three groups: 1) a control-patients newly operated due to scoliosis, patients treated with the traditional growing rod (TGR) and TGR who had rod fracture (FGR) and required a surgical revision. Titanium quantification in blood sample, skin fragment (CT –clean tissue) andmacrosco-pically contaminated tissue located near the implant (DT –dirty tissue) was performed using high-resolution emission spectrometry with excitation in inductively coupled plasma.The mean serum titanium level in control, TGR, and FGR groups were 1.93 ± 0.8, 5.61 ± 0.23, and 4.43 ± 0.1 μg/dm³, respectively. The mean CT titanium level in control, TGR, and FGR groups were 0.0045 ± 0.001, 0.0035 ± 0.001and 0.0065 ± 6.8 mg/g, respectively. The mean DT titanium level in TGR and FGR groups was 0.59 ± 0.02, and 1.022 ± 0.03 mg/g, respectively.Implant leadsto the TIR into tissues and blood. Increasing the number of anchors increases the titanium content inthe CT TGR group. Mechanical damage to the implant has no significant effect on the increase of TIR

Źródło:

Physicochemical Problems of Mineral Processing; 2019, 55, 6; 1442-1449
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 26.

Tytuł:

Study of flotation behavior and mechanism of cervantite activation by copper ions

Autorzy:

Wang, J.
Wang, Y.
Fu, K.
Xu, L.
Wang, Z.
Sun, H.
Xiao, J.

Powiązania:

https://bibliotekanauki.pl/articles/110228.pdf

Data publikacji:

2018

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

flotation
cervantite
copper ions
activation mechanism

Opis:

Copper-ion activation plays a highly important role in cervantite (Sb2O4) flotation. Without metal-ion activation, cervantite cannot be floated by sodium oleate. In this study, flotation tests were conducted to study the effect of Cu2+ on the flotation behaviours of cervantite and quartz (SiO2) as the main gangue mineral. Metal-ion adsorption capacities, zeta potentials, solution chemistry and X-ray photoelectron spectra were analyzed to study the adsorption behavior and mechanism of copper ions and sodium oleate interaction with the minerals surfaces. The results demonstrate that under weakly acidic conditions, cervantite can be flotated and separated from quartz by the addition of copper ions. The reason is that copper ions can be selectively adsorbed on the cervantite surface under weakly acidic conditions, thereby promoting the adsorption of sodium oleate onto the cervantite surface by chemical adsorption. Conversely, copper ions are weakly adsorbed on quartz surfaces below pH 6.1, and sodium oleate cannot be adsorbed on quartz surfaces by chemical adsorption. The hydroxy copper species are integral to the selective activation of cervantite over quartz.

Źródło:

Physicochemical Problems of Mineral Processing; 2018, 54, 3; 814-825
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 27.

Tytuł:

Application of modified maize hull for removal of Cu(II) ions from aqueous solutions

Autorzy:

Ghasemi, S. M.
Mohseni-Bandpei, A.
Ghaderpoori, M.
Fakhri, Y.
Keramati, H.
Taghavi, M.
Moradi, B.
Karimyan, K.

Powiązania:

https://bibliotekanauki.pl/articles/208248.pdf

Data publikacji:

2017

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

heavy metal ions
waste water
Cu(II)
ions
adsorption
biomass
jony metali ciężkich
ścieki
biomasa
adsorpcja

Opis:

Discharge of industrial waste containing heavy metals to the environment is a main concern because of their toxicity to many life forms. Adsorption process is one of the conventional methods in order to adsorb heavy metals from wastewater effluents. Therefore, the removal of Cu(II) from aquatic solutions using modified maize hull was investigated. All experiments were performed in batch conditions. The residual Cu(II) concentration was measured by AAS. Upon increasing the adsorbent dosage, pH, and contact time and decreasing Cu(II) concentration, the removal efficiency of Cu(II) ions increased. In optimum conditions, 50% of copper was removed by modified maize hull. The experimental data were best fitted by the Langmuir type 2 model and the adsorption kinetic model followed a pseudo-second order type 1 model. It seems that the use of the modified maize hull to remove Cu(II) ions is very suitable, low-cost, and efficient.

Źródło:

Environment Protection Engineering; 2017, 43, 4; 93-103
0324-8828

Pojawia się w:

Environment Protection Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 28.

Tytuł:

Removal of Zinc Ions from Aqueous Solutions with the Use of Lignin and Biomass. Part II

Autorzy:

Miros-Kudra, P.
Sobczak, P.
Gzyra-Jagieła, K.
Ciepliński, M.

Powiązania:

https://bibliotekanauki.pl/articles/24200965.pdf

Data publikacji:

2023

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych

Tematy:

lignin
sorption
biomass
zinc ions
water treatment

Opis:

In response to the trend toward sustainable management of by-products from the pulp and paper industry as well as plant waste, practical and economical methods are being developed to use them in a way that does not pose a threat to the environment. The main aim of the research was to study the possibility of using lignin and plant biomass as biosorbents for the removal of zinc ions from aqueous solutions. The secondary aim was to build an optimal multilayer system made of biosorbents selected during the research in order to obtain the highest sorption efficiency and to determine the best conditions of the sorption process. The effectiveness of zinc ion sorption was assessed using an appropriate combination of sorbents such as lignin, oat bran, rice husk, chitosan, pectin, sodium alginate, pine bark, coconut fiber and activated carbon, selected on the basis of literature data and the preliminary results of tests carried out using FTIR and AAS. The main component of the sorption system was lignin separated from black liquor. Results indicate that the best Zn sorption system was based on coconut fiber, lignin, and pine bark, for which the maximum sorption efficiency was 95%. The research also showed that the increase in the process temperature, the mass of biosorbents used and the alkaline pH are the factors that increase the efficiency of the sorption. It can be concluded that lignin and plant biomass can be used as ecological sorbents of zinc ions from water solutions. They are safe for the environment, produced from renewable sources, and are by-products or waste materials, which is part of the sustainable development and circular economy currently promoted in the EU.

Źródło:

Fibres & Textiles in Eastern Europe; 2023, 31, 2; 11--25
1230-3666
2300-7354

Pojawia się w:

Fibres & Textiles in Eastern Europe

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 29.

Tytuł:

Poly(2-acrylamido-2-methyl-1-propane sulfonic acid-co-1-vinyl-2-pyrrolidone) Hydrogel and its use in the Removal of Cd(II), Pb(II) and Cu(II)

Autorzy:

Çavuş, S.
Çakal, E.

Powiązania:

https://bibliotekanauki.pl/articles/1031592.pdf

Data publikacji:

2017-09

Wydawca:

Polska Akademia Nauk. Instytut Fizyki PAN

Tematy:

sorption
heavy metal ions
hydrogels
sulfonic acid

Opis:

Poly(2-acrylamido-2-methyl-1-propanesulfonic acid-co-1-vinyl-2-pyrrolidone), P(AMPS-co-VP), hydrogel was prepared by free radical cross-linking polymerization method. Prepared hydrogel was used in the competitive removal of Cd(II), Pb(II) and Cu(II) ions from aqueous solution. The characterization of P(AMPS-co-VP) before and after sorption was carried out by the Fourier transform infrared spectroscopy, thermogravimetric analysis and scanning electron microscopy. Atomic absorption spectrometer was used to found the concentration of metal ions in the aqueous solution. The selectivity of P(AMPS-co-VP) was as follows: Cd(II)>Pb(II)>Cu(II). Kinetic study showed that competitive removal of heavy metal ions on poly(AMPS-co-VP) was in accordance with a pseudo-second-order model.

Źródło:

Acta Physica Polonica A; 2017, 132, 3; 505-508
0587-4246
1898-794X

Pojawia się w:

Acta Physica Polonica A

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 30.

Tytuł:

Study of Gold, Copper and Nickel Adsorption, from their Acidic Chloride Solutions, Onto Activated Carbon

Autorzy:

Wojnicki, M.
Socha, R. P.
Luty-Błocho, M.
Partyka, B.
Polański, M.
Deszcz, P.
Kołczyk, K.
Żabiński, P.

Powiązania:

https://bibliotekanauki.pl/articles/356223.pdf

Data publikacji:

2018

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

adsorption
gold(III) chloride ions
recovery
recycling

Opis:

In this paper, a simple and effective method for gold recovery is described. The paper describes a way to recover gold onto activated carbon from a synthetic solution of gold(III) chloride. The method can also be used on nickel(II) as well as copper(II) chloride of where the metal ion ratios are comparable to the metal ratios found in some electronic waste. With the use of activated carbon in the process of electrolyte purification it is possible to selectively remove gold in metallic form from the solution. XPS studies have confirmed that metallic gold is present on the carbon surface. A spectrophotometric method was used to determine the concentration of Au(III) in the solution. Different concentration of nickel(II) as well as copper(II) were investigated. In all cases, adsorption and reduction of Au(III) to the metallic form was observed.

Źródło:

Archives of Metallurgy and Materials; 2018, 63, 1; 73-81
1733-3490

Pojawia się w:

Archives of Metallurgy and Materials

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 31.

Tytuł:

Selected methods of electronand ion-diagnostics in tokamak scrape-off-layer

Autorzy:

Sadowski, M. J.

Powiązania:

https://bibliotekanauki.pl/articles/146123.pdf

Data publikacji:

2015

Wydawca:

Instytut Chemii i Techniki Jądrowej

Tematy:

diagnostics
electrons
ions
fusion products
probes
tokamak

Opis:

This invited paper considers reasons why exact measurements of fast electron and ion losses in tokamaks, and particularly i n a scrape-off-layer and near a divertor region, are necessary in order to master nuclear fusion energy production. Attention is also paid to direct measurements of escaping fusion products from D-D and D-T reactions, and in particular of fast alphas which might be used for plasma heating. The second part describes the generation of so-called runaway and ripple-born electrons which might induce high energy losses and cause severe damages of internal walls in fusion facilities. Advantages and disadvantages of different diagnostic methods applied for studies of such fast electrons are discussed. Particular attention is paid to development of a direct measuring technique based on the Cherenkov effect which might be induced by fast electrons in appropriate radiators. There are presented various versions of Cherenkov-type probes which have been developed by the NCBJ team and applied in different tokamak experiments. The third part is devoted to direct measurements of fast ions (including those produced by the nuclear fusion reactions) which can escape from a high-temperature plasma region. Investigation of fast fusion-produced protons from tokamak discharges is reported. New ion probes, which were developed by the NCBJ team, are also presented. For the fi rst time there is given a detailed description of an ion pinhole camera, which enables irradiation of several nuclear track detectors during a single tokamak discharge, and a miniature Thomson-type mass-spectrometer, which can be used for ion measurements at plasma borders.

Źródło:

Nukleonika; 2015, 60, 2; 199-206
0029-5922
1508-5791

Pojawia się w:

Nukleonika

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 32.

Tytuł:

Position of Fe ions in MgO crystalline structure

Autorzy:

Szczerba, J.
Prorok, R.
Stoch, P.
Śnieżek, E.
Jastrzębska, I.

Powiązania:

https://bibliotekanauki.pl/articles/146372.pdf

Data publikacji:

2015

Wydawca:

Instytut Chemii i Techniki Jądrowej

Tematy:

Mössbauer spectroscopy
MgO
Fe ions
crystal structure

Opis:

Magnesium oxide (MgO) is one of the most important raw materials in many branches of industry. Magnesium oxide is a popular refractory raw material because of its high refractoriness and high resistance to basic slags and environment. In many cases, use of MgO is limited by its properties, especially the presence of secondary phases like iron oxides. The amount and distribution of iron oxides can strongly infl uence the technological properties of MgO and depend on the manufacturing method, particularly the heat-treatment process. The aim of the study was to evaluate the infl uence of the heat-treatment process on amount and distribution of iron ions in a magnesium oxide lattice. The 57Fe Mössbauer effect measurements of fused and sintered magnesium oxide samples doped by the iron oxide were conducted. Investigation reveals in both cases the presence of Fe2+ as well as Fe3+ ions. Fe2+ ions occupy Mg2+ octahedral sites in the MgO lattice, whereas the Fe3+ ions are located in highly distorted octahedral coordination. The amount of Fe2+ varies from around 66% for fused samples to 30% for sintered samples.

Źródło:

Nukleonika; 2015, 60, 1; 143-145
0029-5922
1508-5791

Pojawia się w:

Nukleonika

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 33.

Tytuł:

Phase-locking of 19-core Yb3+ - doped optical fibre

Autorzy:

Kochanowicz, M.
Dorosz, D.
Zając, A.

Powiązania:

https://bibliotekanauki.pl/articles/200141.pdf

Data publikacji:

2011

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

multicore optical fibre
fibre lasers
ytterbium ions

Opis:

The supermode generation in a multicore optical fibre laser can be realised by phase-locking of radiation inside of the fibre. The model proposed by authors implies the achievement of supermode generation by exchanging radiation between the cores during the development of the laser action. The analysis of the impact of coupling value between the cores on phase radiation of particular emitters was considered. In the paper the phase-locking of 19-core optical fibre doped with Yb3+ ions is presented. The analysis of material and geometrical parameters of the active 19 -core optical fibre and phase deviation on the beam quality factor of the laser beam in the far-field diffraction region has been analysed. The beam quality factor of the manufactured multicore fibre equals BQF = 0.71, V = 2.4, d = 18 ěm. As a result of the conducted analysis a double-clad 19 – cores optical fibre doped with ytterbium ions has been designed and fabricated and its luminescence spectra and far-field diffraction pattern have been measured. Registered in the experiment in MOFPA system far-field pattern showed centrally located peak of relatively high radiation intensity together with smaller side-lobes, and as such was similar to the pattern which had been obtained numerically.

Źródło:

Bulletin of the Polish Academy of Sciences. Technical Sciences; 2011, 59, 4; 371-379
0239-7528

Pojawia się w:

Bulletin of the Polish Academy of Sciences. Technical Sciences

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 34.

Tytuł:

Influence of active admixtures onto tellurite glass refractive index

Autorzy:

Reben, M.
Wasylak, J.
Jaglarz, J.

Powiązania:

https://bibliotekanauki.pl/articles/200746.pdf

Data publikacji:

2010

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

tellurite glass
rare earth ions
refractive index

Opis:

The goal of this work was to investigate the influence of rare earth ions such as Tm3+, Yb3+ on physico-chemical properies of tellurite glass from the TeO2-WO3-PbO-PbF2-Na2O system. The thermal characteristic of tellurite glass Tm3+, Yb3+ doped have been presented. The effect of the glass crystallization on thermal stability of the glass and crystallizing phases formed upon heat treatment were investigated by DTA/DSC/, XRD methods. The spectral dependence of ellipsometric angles of the tellurite glass samples, have been studied. The influence of ions of rare earth elements, i.e. Tm 3+ and Yb3+, onto changes of refractive index of glass P1 (without RE admixture) were examined. The optical measurements were conducted on Woollam M2000 spectroscopic ellipsometer, in spectral range of 190–1700 nm.

Źródło:

Bulletin of the Polish Academy of Sciences. Technical Sciences; 2010, 58, 4; 519-522
0239-7528

Pojawia się w:

Bulletin of the Polish Academy of Sciences. Technical Sciences

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 35.

Tytuł:

Adsorption behavior of calcium ions and its effect on cassiterite flotation

Autorzy:

Chen, Yumeng
Feng, Dongxia
Tong, Xiong

Powiązania:

https://bibliotekanauki.pl/articles/110731.pdf

Data publikacji:

2019

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

cassiterite
calcium ions
adsorption
flotation
salicylhydroxamic acid

Opis:

Naturally, most of the cassiterite co-exists with sparingly soluble calcite, which makes it difficult to be fully utilized. Due to the adsorption of calcium ions dissolved from calcite, surface properties of cassiterite and its floatability can be influenced. Adsorption tests show calcium ions can adsorb on cassiterite surface. In the presence of Ca2+, the zeta potentials of cassiterite shift to more positive values and the isoelectric point of cassiterite increases from pH 4.4 to pH 4.9. XPS results show that after calcium ions treatment, a strong calcium spectral peak at 347.65 eV is detected on the cassiterite surface and the chemical circumstance of oxygen atoms is changed. The presence of Ca2+ can significantly depressed the flotation behavior of cassiterite with salicylhydroxamic acid (SHA) as collector. Its recovery is decreased by 26.03% compared to that without Ca2+ at SHA dosage of 8.0×10-4 mol/dm3. When increasing SHA concentration to 9.0×10-4 mol/dm3 and above, the depression effect is partly compensated and the recovery rises by about 20%. Contact angle values of cassiterite measured by the bubble method correspond well to the flotation performance. Hence the depression mechanism of Ca2+ in cassiterite flotation can be interpreted in two aspects: 1) the consumption of SHA due to complexation reactions in pulp; 2) a decrease of effective adsorption site for SHA on cassiterite because of the adsorption of Ca2+.

Źródło:

Physicochemical Problems of Mineral Processing; 2019, 55, 1; 258-267
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 36.

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

/5

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Skocz do pozycji: 37.

Tytuł:

Wyznaczanie współczynnika dyfuzji chlorków w betonie na podstawie badań migracji jonów w polu elektrycznym
Determination of the diffusion coefficient of chlorides in concrete based on tests of the migration of ions in an electric field

Autorzy:

Szweda, Z.
Zybura, A.

Powiązania:

https://bibliotekanauki.pl/articles/163453.pdf

Data publikacji:

2012

Wydawca:

Polski Związek Inżynierów i Techników Budownictwa

Tematy:

beton
korozja chlorkowa
migracja jonów chlorkowych
współczynnik dyfuzji chlorków
badanie w polu elektrycznym
concrete
chloride ions corrosion
chloride ions migration
chloride ions diffusion coefficient
testing in electric field

Opis:

Na podstawie uzyskanego eksperymentalnie pod wpływem sił pola elektrycznego rozkładu stężenia chlorków w betonie oraz rozwiązania teoretycznego, wyznaczono wartości współczynników dyfuzji. Wartości te zweryfikowano, porównując obliczony rozkład chlorków z uzyskanym w badaniach dyfuzyjnych.
Based on a distribution of chloride concentration in concrete, obtained experimentally under the forces of an electrical field, as well as theoretical considerations, values of diffusion coefficients were determined. These values were verified by comparing the calculated chloride distribution with that obtained in diffusion tests.

Źródło:

Przegląd Budowlany; 2012, R. 83, nr 6, 6; 60-62
0033-2038

Pojawia się w:

Przegląd Budowlany

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 38.

Tytuł:

Signalling: basics and evolution.

Autorzy:

Williams, Robert

Powiązania:

https://bibliotekanauki.pl/articles/1043264.pdf

Data publikacji:

2004

Wydawca:

Polskie Towarzystwo Biochemiczne

Tematy:

pumps
signalling
metal ions
receptors
donors
substrates

Opis:

Signalling concerns the transfer of information from one body, a source, to another, a receiver in order to stimulate activity. The problem arises with the word information. It is defined as what is transferred in a sequence of things, say between people, e.g. words or signs. The idea of signalling between people is then obvious but it is not clear in cell biology. Information transfer, signalling, is required for the organisation of all cellular activity but we must ask what is transferred and how is it transmitted and received? Sometimes it is assumed that all information, i.e. organisation in a cell, is represented in the DNA sequence. This is incorrect. We shall show that the environment is a second source of information concerning material and energy. The receiving party from both DNA and the environment is general metabolism. The metabolism then signals back and sends information to both DNA and uptake from the environment. Even then energy is needed with machinery to send out all signals. This paper examines the way signalling evolved from prokaryotes through to man. In this process the environmental information received increased to the extent that finally the brain is a phenotypic as much as a genotypic organ within a whole organism. By phenotypic we mean it is organised by and interactive with information from the environment.

Źródło:

Acta Biochimica Polonica; 2004, 51, 2; 281-298
0001-527X

Pojawia się w:

Acta Biochimica Polonica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 39.

Tytuł:

Soft Ion Divalent Metals toward Adsorption on Zn/Al-POM Layered Double Hydroxide

Autorzy:

Silaen, Luna
Elfita, -
Mohadi, Risfidian
Normah, -
Juleanti, Novie
Palapa, Neza Rahayu
Lesbani, Aldes

Powiązania:

https://bibliotekanauki.pl/articles/2027762.pdf

Data publikacji:

2021

Wydawca:

Polskie Towarzystwo Inżynierii Ekologicznej

Tematy:

soft divalent metal ions
adsorption
polyoxometalate
regeneration

Opis:

Development of Zn/Al layered double hydroxide by intercalation using polyoxometalate (POM) $K_4 [α-SiW_12O_40]$ to Zn/Al-POM was investigated. The success of the modification is evidenced by the XRD, FT-IR, and BET characterization data. XRD characterization showed an increase in the interlayer distance from 8.59 Å in Zn/Al LDHs to 10.26 Å in Zn/Al-POM. This success is also supported by the FT-IR data with the appearance of vibrations around $779–979 cm^{-1}$ which indicates the vibration of the polyoxometalate compound in Zn/Al-POM. Other supporting data in the form of BET also prove an increase in surface area from 1.968 $m^2$/g in Zn/Al LDHs to 14.042 $m^2$/g Zn/Al-POM. The ability of Zn/Al-POM as an adsorbent is proven through several parameters such as kinetics, isotherm, thermodynamics, and regeneration for $Cd^{2+}$, $Pb^{2+}$, $Ni^{2+}$, and $Co^{2+}$. Adsorption kinetics showed that Zn/Al-POM was more likely to follow the pseudo-second-order adsorption kinetics model for $Cd^{2+}$, $Pb^{2+}$, $Ni^{2+}$, and $Co^{2+}$. The results of determining the adsorption isotherm parameters of Zn/Al-POM tend to follow the Freundlich isotherm model with a maximum adsorption capacity of 74.13 mg/g on $Pb^{2+}$. The regeneration process showed that Zn/Al-POM was more resistant than Zn/Al LDHs up to 3 cycles. It was proven that Zn/Al-POM was able to survive in the last cycle up to 69.19% on $Ni^{2+}$.

Źródło:

Journal of Ecological Engineering; 2021, 22, 10; 109-120
2299-8993

Pojawia się w:

Journal of Ecological Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 40.

Tytuł:

The use of ion exchangers for removing cobalt and nickel ions from water solutions
Wykorzystanie wymieniaczy jonowych do usuwania jonów kobaltu i niklu z roztworów wodnych

Autorzy:

Bożęcka, A. M.
Sanak-Rydlewska, S.

Powiązania:

https://bibliotekanauki.pl/articles/219593.pdf

Data publikacji:

2018

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

żywice jonowymienne
jony kobaltu i niklu
kinetyka wymiany jonowej
ion exchange resins
cobalt ions
nickel ions
ion exchange kinetics

Opis:

The paper presents results of research on cobalt and nickel ions removal from monocomponent solutions using Purolite ion exchange resins. It has been shown that C 160 ion exchange resin has the best sorption properties for both ions (Qe - 72.5 mg Co/g and 88.2 mg Ni/g). Regeneration process of this ion exchanger has high efficiency, achieving about 93% for cobalt ions and about 84% in case of nickel ions. It has been shown that the use of ion exchange method with suitable ion exchange resins guarantees effective removal of cobalt and nickel ions from solutions with very high concentrations corresponding to contents of these metals in industrial wastewaters (e.g. galvanic). In case of C 160 ion exchange resin, after the sorption process is carried out in one 50 minute cycle, the cobalt concentration decreased from about 30 000 mg/L to about 9 500 mg/L (approx. 68%), whereas nickel concentration reached about 6 300 mg/L (approx. 79%). Studied chelating resins don’t have such high sorption capacities. In their case, it is required to convert cobalt and nickel ions into complex forms. The kinetics of studied processes were described by pseudo-second order equations.
Rozwój przemysłu znacznie wpływa na stan środowiska naturalnego. Zanieczyszczenia emitowane do wód, gleb i powietrza na skutek działalności człowieka stanową zagrożenie dla zdrowia i życia organizmów żywych. Wśród tych substancji, jako szczególnie niebezpieczne wymienia się metale toksyczne. W ich grupie znajduje się również kobalt i nikiel, których głównym źródeł emisji do środowiska jest przemysł elektrochemiczny i metalurgiczny. Pierwiastki te są stosunkowo rzadkimi i cennymi metalami, dlatego ważne jest poszukiwanie dodatkowych źródeł i metod ich odzysku. Przedmiotem badań były żywice jonowymienne firmy Purolite, które zastosowano do usuwania jonów kobaltu i niklu z roztworów monoskładnikowych o stężeniach odpowiadających zawartościom tych metali w ściekach galwanicznych (ok. 30 000 mg/dm3). W oparciu o wyniki badań można stwierdzić, że najlepsze właściwości sorpcyjne zarówno w stosunku do jonów kobaltu jak i niklu wykazuje kationit C 160. Zdolności sorpcyjne pozostałych jonitów maleją w szeregu S 950 > S 930 > S 910 > S 920. W kolejnym etapie sprawdzono możliwość regeneracji badanych jonitów za pomocą 10% roztworów kwasu azotowego(V) lub kwasu solnego. Proces regeneracji jonów kobaltu zachodzi z większą wydajnością w porównaniu do jonów niklu. Wykazano, że metodą wymiany jonowej z użyciem odpowiednich żywic jonowymiennych można skutecznie usuwać jony kobaltu i niklu z roztworów o bardzo wysokich stężeniach, odpowiadających zawartościom tych metali w ściekach przemysłowych (m.in. galwanicznych). W przypadku jonitu C 160, po procesie sorpcji wykonanym w jednym, 50 minutowym cyklu, stężenie kobaltu obniżyło się z ok. 30 000 mg/dm3 do wartości ok. 9500 mg/dm3 (ok. 68%), natomiast stężenie niklu osiągnęło wartość ok. 6300 mg/dm3 (ok. 79%) (Tab. 2 i 3). Badane jonity chelatujące nie osiągają tak wysokich pojemności sorpcyjnych. W ich przypadku wymagane jest przeprowadzenie jonów kobaltu i niklu w formy kompleksowe.

Źródło:

Archives of Mining Sciences; 2018, 63, 3; 633-646
0860-7001

Pojawia się w:

Archives of Mining Sciences

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 41.

Tytuł:

Analiza regresji izoterm sorpcji jonów miedzi i kadmu na iłach smektytowych
Regression analysis for the sorption isotherms of copper and cadmium ions on smectite clays

Autorzy:

Kyzioł-Komosińska, J.
Pająk, M.

Powiązania:

https://bibliotekanauki.pl/articles/2062911.pdf

Data publikacji:

2009

Wydawca:

Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy

Tematy:

sorpcja
analiza regresji
jony kadmu
jony miedzi
iły smektytowe
sorption
regression analysis
cadmium ions
copper ions
smectite clays

Opis:

Przeprowadzono badania sorpcji jonów Cd(II) i Cu(II) na cząstkach iłu smektytowego. Do interpretacji wyników zastosowano izotermę Langmuira i Freundlicha. Parametry w równaniach oszacowano stosując metodę regresji liniowej i nieliniowej oraz metodę regresji liniowej dla dwóch zakresów stężeń początkowych jonów metali w roztworze. Najlepsze wyniki osiągnięto stosując metodę regresji nieliniowej lub metodę regresji liniowej dla dwóch zakresów stężeń początkowych jonów metali.
The sorption of Cd(II) and Cu(II) ions onto smectite clays was studied. Equilibrium isotherms were analyzed using the Langmuir and Freundlich isotherms. A comparison between a linear and non-linear method of estimating the isotherm parameters was made. The results show that the non-linear and linear methods in two ranges of initial metal concentrations could be the best way to obtain the parameters.

Źródło:

Biuletyn Państwowego Instytutu Geologicznego; 2009, 436, z. 9/2; 309-316
0867-6143

Pojawia się w:

Biuletyn Państwowego Instytutu Geologicznego

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 42.

Tytuł:

Activation of quartz flotation by Cu2+, Ni2+ in the sodium ethylxanthogenate (EX) system

Autorzy:

Liu, Yang
Tong, Xiong
Xie, Rui-Qi
Xie, Xian
Song, Qiang
Fan, Pei-Qiang

Powiązania:

https://bibliotekanauki.pl/articles/24085981.pdf

Data publikacji:

2023

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

quartz
flotation
ions activation
sodium ethylxanthogenate
adsorption mechanism

Opis:

During the flotation of metal sulfide minerals, due to the interference of unavoidable ions, the quartz also partially floats in some cases. The studies on the mechanism of quartz being activated and floating up are still insufficient. In this study, the influence of the Cu2+ and Ni2+ unavoidable ions on the floatation of quartz was studied by micro-flotation experiments, adsorption detection, zeta potential measurement, solution composition calculation, infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) analyses, and atomic force microscopy (AFM) observation. This provides a theoretical reference for further understanding the mechanism of sodium ethylxanthogenate and quartz surface, as well as the development of a new quartz depressant. The results of flotation showed that after activation by Cu2+ (1×10-4 mol/dm3) and Ni2+ (5×10-5 mol/dm3), the quartz was captured by sodium ethylxanthogenate (EX: 1.4×10-4 mol/dm3) under alkaline conditions (pH=10), while the best recoveries were obtained as 80% and 43%, respectively. The results of adsorption and zeta potential measurements showed that the precipitation rate of Cu2+ was greater than that of Ni2+ under alkaline conditions. Additionally, both Cu2+ and Ni2+ electrostatically adsorbed on the quartz surface and changed the zeta potential of quartz. The solution composition calculation further showed that Cu(OH)+, Cu(OH)2(s), and Ni(OH)+, Ni(OH)2(s) were the main components in the solution under alkaline conditions. The FT-IR and XPS analyses and AFM observations demonstrated that Cu and Ni species adsorbed on O atoms on the quartz surface, providing active sites for EX adsorption, and EX combines with Cu and Ni species on the quartz surface to generate -O-Cu-EX and -O-Ni-EX complexes. Finally, the quartz floated up due to the formation of hydrophobic products and firm adsorption.

Źródło:

Physicochemical Problems of Mineral Processing; 2023, 59, 2; art. no. 166368
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 43.

Tytuł:

Influence of Fluoride Ions in Artificial Saliva Solution to Corrosion Behavior of Ti-6Al-4V and Ti-10Mo-4Zr Titanium Alloys

Autorzy:

Loch, J.
Krawiec, H.

Powiązania:

https://bibliotekanauki.pl/articles/106985.pdf

Data publikacji:

2018

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

titanium alloys
artificial saliva solution
fluoride ions
corrosion

Opis:

Titanium alloys used in medical applications (especially dentistry) are exposed to the actions of various compounds that appear periodically in the mouth. Fluorine compounds are dangerous for the surface of titanium alloys, because they generate a dissolution of the passive layer. In this way, they destroy the surface of dental implants and cause the absorption of metal ions into the human body. The presented work was aimed to describe the effect of fluoride ions on the corrosive behavior of the commercial Ti-6Al-4V and new Ti-10Mo-4Zr alloys that can be used in stomatology. Electrochemical measurements such as open circuit potential (OCP), linear sweet voltamperometry (LSV) and impedance spectroscopy (EIS) were performed to get information on the corrosive behavior of titanium in artificial saliva solutions (MAS) with different concentrations of NaF. It has been revealed that a high concentration of fluoride ions enhance the current density in the anodic domain, especially for the Ti-10Mo-4Zr alloy. EIS measurements performed at a potential of 0.5 V vs. AgCl (3 M KCl) show that the Ti-10Mo-4Zr alloy has a typical two-layer structure of its passive film. This passive film consists of the outer and inner layers, respectively. The resistance of the outer layer is significantly lower than the resistance of the inner layer.

Źródło:

Journal of Casting & Materials Engineering; 2018, 2, 3; 57-62
2543-9901

Pojawia się w:

Journal of Casting & Materials Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 44.

Tytuł:

Hydroksyapatyt modyfikowany jonami selenianowymi (IV) – nowy materiał o potencjalnym znaczeniu biomedycznym
Hydroxyapatite doped with selenite ions – a new material for potential biomedical applications

Autorzy:

Kolmas, J.
Olędzka, E.
Sobczak, M.
Nałęcz-Jawecki, G.

Powiązania:

https://bibliotekanauki.pl/articles/284754.pdf

Data publikacji:

2013

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Polskie Towarzystwo Biominerałów

Tematy:

hydroksyapatyty
jony selenianowe
biomateriały
hydroxyapatite
selenite ions
biomaterials

Źródło:

Engineering of Biomaterials; 2013, 16, no. 122-123 spec. iss.; 10-11
1429-7248

Pojawia się w:

Engineering of Biomaterials

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 45.

Tytuł:

Magnetic system of the heavy ion cyclotron for track membranes production

Autorzy:

Alenitsky, Y.
Zaplatin, N.
Onischenko, L.
Samsonov, E.
Chesnov, A.

Powiązania:

https://bibliotekanauki.pl/articles/148719.pdf

Data publikacji:

2003

Wydawca:

Instytut Chemii i Techniki Jądrowej

Tematy:

cyclotron
magnetic system
sector shim
heavy ions beam

Opis:

A heavy ion fixed energy cyclotron based on a conventional magnet with a pole diameter of 1.6 m is designed and constructed in JINR. Ions with A/Z = 5 are accelerated up to the energy E = 2.4 MeV/nucleon. The isochronous magnetic field is formed by four pairs of sector shims. The beam phase shift in formed field is less than š15°RF, and the first harmonic of magnetic field is less than 3 G for all radii of the beam acceleration. Power consumption of magnet is 25 kW. The ECR source with an intensity of 3.5 × 1012 ions/s is used as an ion source. The extracted beam (~1011 ions/s) is intended for the track membrane production.

Źródło:

Nukleonika; 2003, 48,suppl.2; 55-57
0029-5922
1508-5791

Pojawia się w:

Nukleonika

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 46.

Tytuł:

XAFS in the tracking of reactions in aqueous solution: a case of redox reaction between [AuCl4]- complex ions and ethanol
Metoda XAFS w badaniach reakcji zachodzących w roztworach wodnych: przykład reakcji redoks pomiędzy jonami kompleksowymi [AuCl4]- i alkoholem etylowym

Autorzy:

Pacławski, K.
Sikora, M.

Powiązania:

https://bibliotekanauki.pl/articles/355830.pdf

Data publikacji:

2012

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

XAFS
XANES
redox reaction
gold complex ions
ethanol

Opis:

In this work the potential application of synchrotron radiation in the studies of reaction kinetics in aqueous phase were presented. After short introduction describing principles of technique and potential application of XAFS for the structural studies of reacting species, the experimental results of kinetic measurements of reaction between gold(III) chloride complex ions and ethanol were presented. Analyzing the changes of absorption intensity in the XANES spectra registered at Au-L &sub3; edge during the reaction, the change of the valence state of Au central atom (form 3+to 0) of reacting complex ion was determined. Moreover, empirical XANES data gave the chance to register the kinetic curve and to determine the rate constant of the studied reaction. It was found that reaction is relatively slow (second-order rate constant k = 3.66 · 10 &sup-5; M ;sup-1;s) and lead to the gold metallic phase formation in the system. Applying the continuous-flow method, within the first 600 ms of reaction the changes in XANES spectra were registered. From the obtained results, supported with numerical calculations, two intermediate forms of adducts appearing prior the electron transfer were suggested. It was concluded that when the classic methods, e.g. UV-Vis spectrophotometry, cannot be applied to studies of kinetics of reactions in aqueous solution, the XAFS technique can be a valuable and substitutive (or supplementary) tool for such measurements.
W pracy przedstawiono potencjalne możliwości zastosowania promieniowania synchrotronowego w badaniach nad kinetyka reakcji przebiegających w roztworach wodnych. We wstępie, omówiono podstawy techniki rentgenowskiej analizy struktury nadsubtelnej (XAFS) i jej możliwości zastosowania w badaniach strukturalnych związków chemicznych w fazie ciekłej. Zaprezentowano również dane eksperymentalne z pomiarów XAFS dotyczące kinetyki reakcji pomiędzy chlorkowymi kompleksami złota(III) i alkoholem etylowym. Z analizy zmian intensywności absorpcji widm XANES rejestrowanych przy krawędzi L &sub3; złota określono zmianę stopnia utlenienia atomu centralnego Au (z 3+ do 0) reagującego kompleksu. Ponadto, dane empiryczne pozwoliły na wyznaczenie krzywej kinetycznej oraz określenie drugorzędowej wartości stałej szybkości reakcji (k = 3.66 ·10 &sup-5; M &sup-1;s). W wyniku analizy widm XANES potwierdzono powstawanie faza metalicznej złota w układzie. Stosując metodę ciągłego przepływu reagentów, zarejestrowano zmiany w widmie XANES w ciągu 600 ms od rozpoczęcia reakcji.Na podstawie zarejestrowanych widm oraz przeprowadzonych obliczeń numerycznych zasugerowano dwie możliwe struktury adduktu tworzącego się przed właściwym transferem elektronu w reakcji redoks. Z przeprowadzonych eksperymentów wynika, ze w układach, w których nie jest możliwe stosowanie spektrofotometrii UV-Vis, metoda XAFS może być zastępczym i obiecującym narzędziem do badań kinetyki reakcji.

Źródło:

Archives of Metallurgy and Materials; 2012, 57, 4; 1011-1020
1733-3490

Pojawia się w:

Archives of Metallurgy and Materials

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 47.

Tytuł:

Studies on the production of glucose isomerase by Bacillus licheniformis

Autorzy:

Nwokoro, O.

Powiązania:

https://bibliotekanauki.pl/articles/778827.pdf

Data publikacji:

2015

Wydawca:

Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie

Tematy:

glucose isomerase
carbon sources
nitrogen sources
metal ions

Opis:

This work reports the effects of some culture conditions on the production of glucose isomerase by Bacillus licheniformis. The bacterium was selected based on the release of 3.62 mg/mL fructose from the fermentation of glucose. Enzyme was produced using a variety of carbon substrates but the highest enzyme activity was detected in a medium containing 0.5% xylose and 1% glycerol (specific activity = 6.88 U/mg protein). Media containing only xylose or glucose gave lower enzyme productivies (specific activities= 4.60 and 2.35 U/mg protein respectively). The effects of nitrogen substrates on glucose isomerase production showed that yeast extract supported maximum enzyme activity (specific activity = 5.24 U/mg protein). Lowest enzyme activity was observed with sodium trioxonitrate (specific activity = 2.44 U/mg protein). In general, organic nitrogen substrates supported higher enzyme productivity than inorganic nitrogen substrates. Best enzyme activity was observed in the presence of Mg2+ (specific activity = 6.85 U/mg protein) while Hg2+ was inhibitory (specific activity = 1.02 U/mg protein). The optimum pH for best enzyme activity was 6.0 while optimum temperature for enzyme production was 50oC.

Źródło:

Polish Journal of Chemical Technology; 2015, 17, 3; 84-88
1509-8117
1899-4741

Pojawia się w:

Polish Journal of Chemical Technology

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 48.

Tytuł:

DFT and TOF-SIMS study of the interaction between hydrogen sulfide ion and malachite (–201) surface

Autorzy:

Mao, Yingbo
Wu, Dandan
Huang, Lingyun

Powiązania:

https://bibliotekanauki.pl/articles/1447053.pdf

Data publikacji:

2021

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

malachite
hydrogen sulfide ions
sulfidation
DFT
TOF-SIMS

Opis:

In this paper, the mechanism of interaction between hydrogen sulfide ions and malachite was investigated using density functional theory (DFT) calculations and time of flight secondary ion mass spectrometry (TOF-SIMS). The DFT calculations showed that HS− adsorption on the malachite (−201) surface was stronger than that of S adsorption resulting from the higher number of electron transfers in the solution which accelerated the sulfidation reaction rate. Density of states (DOS) analysis showed that the near Fermi level was jointly contributed to by the Cu 3d, O 2p, O 2S, and S 3P orbits after adsorption of HS− on the malachite (–201)surface. It was found that the 2p orbital of O and the 3p orbital of S overlapped, indicating that S not only reacted with Cu, but also with O. The TOF-SIMS detected S− and CuS2− fragment ion peaks in the 0−150 m/z negative segment of mass spectra. TOF-SIMS also showed that copper sulfide films of certain thicknesses were formed, demonstrating the effectiveness of hydrogen sulfide sulfidation in flotation processes.

Źródło:

Physicochemical Problems of Mineral Processing; 2021, 57, 5; 71-79
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 49.

Tytuł:

Wpływ zjonizowanego powietrza na organizm ludzki
Impact of ionized air upon human body

Autorzy:

Moga, M.
Małecka, I.

Powiązania:

https://bibliotekanauki.pl/articles/407560.pdf

Data publikacji:

2011

Wydawca:

Instytut Badawczo-Rozwojowy Inżynierii Lądowej i Wodnej Euroexbud

Tematy:

jony ujemne
jony dodatnie
organizm ludzki
zagrożenia mikrobiologiczne
dezynfekcja powietrza
negative ions
positive ions
human body
microbiological hazards
air disinfection

Opis:

Wpływ zjonizowanego powietrza na organizm ludzki zależy od wielkości jonów i ich biegunowości oraz koncentracji ich w powietrzu, a także od właściwości fizykochemicznych nośników jonów (aerozole, bakterie). Głównym źródłem energii jonizującej atomy i molekuły gazów wchodzących w skład powietrza atmosferycznego jest promieniowanie emitowane przez pierwiastki radioaktywne znajdujące się w powietrzu i skorupie ziemskiej. Z dużą dozą ostrożności należy podchodzić do sztucznej jonizacji w pomieszczeniach, w których nie dokonano liczbowo pomiarów ich koncentracji. W celu wyeliminowania zagrożeń mikrobiologicznych w układach instalacji wentylacyjnej należy poddać powietrze skutecznej dezynfekcji. Jony ujemne powietrza przyspieszają reakcje biologiczne, a mianowicie poprawiają zdolność koncentracji, przyspieszają gojenie się ran, zmniejszają uczucie bólu, ale z kolei przyspieszają wzrost komórek nowotworowych. Natomiast jony dodatnie powodują osłabienie, ból głowy, otępienie, zwiększone zapotrzebowanie na tlen oraz występujące także nierzadko objawy suchości w ustach i jamie nosowej.
The impact of ionized air upon the human body depends on the size of ions, their polarity and concentration in the air as well as physicochemical properties of ion carriers (aerosols, bacteria). The main source of energy ionizing gas atoms and molecules forming the atmospheric air is radiation emitted by radioactive elements found in the air and the earth's crust. A very cautious approach must be assumed when considering artificial ionization in rooms where their concentration has not been measured. In order to eliminate microbiological hazards in ventilation systems the air should be subject to effective disinfection. Negative air ions accelerate biological reactions, improve concentration ability, accelerate healing of wounds, reduce feeling of pain, however, they support growth of cancer cells. On the other hand, positive ions cause fatigue, headache, stupefaction, increased demand for oxygen and frequent symptoms of dryness in the mouth and nasal cavity.

Źródło:

Zeszyty Naukowe. Inżynieria Lądowa i Wodna w Kształtowaniu Środowiska; 2011, 4; 26-29
2082-6702

Pojawia się w:

Zeszyty Naukowe. Inżynieria Lądowa i Wodna w Kształtowaniu Środowiska

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 50.

Tytuł:

Transient induced molecular negative ions formed in cold electron collisions with polarized molecules

Autorzy:

Toader, E. I.
Graham, W. G.

Powiązania:

https://bibliotekanauki.pl/articles/147748.pdf

Data publikacji:

2008

Wydawca:

Instytut Chemii i Techniki Jądrowej

Tematy:

interaction processes in plasmas
new negative molecular ions

Opis:

Using a relatively simple semiclassical model, it is shown that transient, induced molecular negative ions (TIMNI), are produced through a potential barrier interaction between cold electron collisions and polarizable molecules in plasma. Such new negative ions lead to radio-frequency absorption in such discharges. The calculated radio-frequency absorption frequencies are consistent with earlier experimental measurements.

Źródło:

Nukleonika; 2008, 53, 3; 123-126
0029-5922
1508-5791

Pojawia się w:

Nukleonika

Dostawca treści:

Biblioteka Nauki

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