| 1. |
- Makarov, D.V., et al.
(författare)
-
Electrochemical oxidation of galenite in carbonate solutions
- 2004
-
Ingår i: Russian journal of applied chemistry. - 1070-4272 .- 1608-3296. ; 77:6, s. 921-924
-
Tidskriftsartikel (refereegranskat)abstract
- Linear voltammetry, X-ray phase and differential thermal analyses, diffuse reflection IR Fourier spectroscopy, Raman spectroscopy, and scanning electron microscopy (SEM) were used to study the electrochemical oxidation of galenite in carbonate electrolytes.
|
|
| 2. |
- Makarov, D.V., et al.
(författare)
-
Electrooxidation of pentlandite in a carbonate solution
- 2004
-
Ingår i: Russian journal of electrochemistry. - 1023-1935 .- 1608-3342. ; 40:4, s. 420-423
-
Tidskriftsartikel (refereegranskat)abstract
- Electrooxidation of pentlandite in a carbonate solution involves the formation of surface sulfide minerals of nickel and iron of variable composition, sulfur, and iron and nickel hydroxides. In parallel, sulfide sulfur oxidizes in a narrow potential range to sulfate ions.
|
|
| 3. |
- Maslova, M. V., et al.
(författare)
-
A study of structure and surface properties of cleaved mica particles
- 2003
-
Ingår i: Russian journal of applied chemistry. - 1070-4272 .- 1608-3296. ; 76:6, s. 867-870
-
Tidskriftsartikel (refereegranskat)abstract
- The structure of cleaved mica particles and the influence of cleavage conditions on surface prop- erties of mica were studied by IR spectroscopy.
|
|
| 4. |
- Kalinkin, Alexander M., et al.
(författare)
-
Surface oxidation of synthetic pyrrhotite during wetting-drying treatment
- 2000
-
Ingår i: Environmental Engineering Science. - : Mary Ann Liebert Inc. - 1092-8758 .- 1557-9018. ; 17:6, s. 329-335
-
Tidskriftsartikel (refereegranskat)abstract
- The surface changes of synthetic hexagonal pyrrhotite Fe[10]S[11] during laboratory wetting-drying treatment at 45°C were investigated using FTIR (DRIFT) spectroscopy, FTIR Raman microscopy, and scanning electron microscopy. α-FeO(OH) (goethite) and elemental sulphur were the main products of the surface pyrrhotite oxidation. The formation of goethite and elemental sulphur was studied on the basis of the corrosion theory and using a potential-pH (Pourbaix) diagram. The appearance of oxidation products on the surface of pyrrhotite grains was detected between 10 and 20 h of treatment. The obtained results can be used for comparison of oxidation processes of synthetic pyrrhotite with that of natural sulphide minerals in dumps.
|
|
| 5. |
- Kalinkina, Elena V., et al.
(författare)
-
Sorption of atmospheric carbon dioxide and structural changes of Ca and Mg silicate minerals during grinding : I. Diopside
- 2001
-
Ingår i: International Journal of Mineral Processing. - 0301-7516 .- 1879-3525. ; 61:4, s. 273-288
-
Tidskriftsartikel (refereegranskat)abstract
- Processes which occur during dry grinding of the magnesium and calcium silicate minerals enstatite MgSiO3, åkermanite Ca2MgSi2O7 and wollastonite CaSiO3, have been studied with the use of diffuse reflectance Fourier transform infrared spectroscopy (DRIFT), powder X-ray diffraction, 29Si MAS-NMR spectroscopy, CO2-content analysis, and BET surface area measurements. It has been found that the extensive sorption of atmospheric CO2 (carbonization) by the ground mineral that was reported earlier for diopside CaMgSi2O6 also occurs for the minerals included in this study. The shape and position of the double peak of the CO32--group in the 1430-1515 cm-1 region in the FT-IR spectra of ground minerals are similar to that of ground diopside. CO2-content analysis and BET surface area measurements show that carbonate groups are present not only at the surface but also in the bulk of the ground minerals. The degree of carbonization of silicate depends on its calcium content. The higher the fraction of Ca in octahedral positions in the silicate structures, the higher the degree of carbonization. For synthetic wollastonite CaSiO3, which is a pure calcium silicate, the degree of carbonization is 102.6 mg CaCO3 per gram of sample after 36 h of grinding. The structure of silicate appears to be less important for the degree of carbonization during grinding.
|
|
| 6. |
- Kalinkina, Elena V., et al.
(författare)
-
Sorption of atmospheric carbon dioxide and structural changes of Ca and Mg silicate minerals during grinding: II. Enstatite, åkermanite and wollastonite
- 2001
-
Ingår i: International Journal of Mineral Processing. - 0301-7516 .- 1879-3525. ; 61:4, s. 289-299
-
Tidskriftsartikel (refereegranskat)abstract
- Processes which occur during dry grinding of the magnesium and calcium silicate minerals enstatite MgSiO3, åkermanite Ca2MgSi2O7 and wollastonite CaSiO3, have been studied with the use of diffuse reflectance Fourier transform infrared spectroscopy (DRIFT), powder X-ray diffraction, 29Si MAS-NMR spectroscopy, CO2-content analysis, and BET surface area measurements. It has been found that the extensive sorption of atmospheric CO2 (carbonization) by the ground mineral that was reported earlier for diopside CaMgSi2O6 also occurs for the minerals included in this study. The shape and position of the double peak of the CO32--group in the 1430-1515 cm-1 region in the FT-IR spectra of ground minerals are similar to that of ground diopside. CO2-content analysis and BET surface area measurements show that carbonate groups are present not only at the surface but also in the bulk of the ground minerals. The degree of carbonization of silicate depends on its calcium content. The higher the fraction of Ca in octahedral positions in the silicate structures, the higher the degree of carbonization. For synthetic wollastonite CaSiO3, which is a pure calcium silicate, the degree of carbonization is 102.6 mg CaCO3 per gram of sample after 36 h of grinding. The structure of silicate appears to be less important for the degree of carbonization during grinding.
|
|
| 7. |
- Lewellen, JW, et al.
(författare)
-
Present status and recent results from the APS SASE FEL
- 2002
-
Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0167-5087. ; 483:1-2, s. 40-45
-
Tidskriftsartikel (refereegranskat)abstract
- The Low-Energy Undulator Test Line (LEUTL) at the Advanced Photon Source, Argonne National Laboratory, is intended to demonstrate the basic operation of a SASE-based free-electron laser. Goals include comparison of experimental results With theoretical predictions and scaling laws, identification of problems relevant to fourth-generation light source construction and operation and the means of addressing them, the development of operational and diagnostic techniques to optimize SASE FEL performance and increase repeatability from run to run. and performance of initial pioneering experiments capable of exploiting the unique properties of the laser. The basic layout and operational philosophy of the LEUTL experiment is presented. A summary of past results, including saturation, is reviewed, and a description of recent results is presented. We conclude with future plans, which include pressing to shorter wavelengths and incorporating user experiments into the LEUTL experimental program.
|
|
| 8. |
- Makarov, Alexandre A., et al.
(författare)
-
Metastable entangled states of atomic systems in macroscale: radiation dynamics and spectrum
- 2004
-
Ingår i: International Workshop on Quantum Optics 2003 (Proceedings of the SPIE). - : SPIE. - 0819453250 ; 5402, s. 54-64
-
Konferensbidrag (refereegranskat)abstract
- Dynamics of spontaneous decay and corresponding emission spectrum areexactly treated for a system of two identical two-level atoms in 1D.Just a one-dimensional case is considered in order to maximally extractan information on mutual influence of spatially remote atoms through theradiation field. As a result, an effect is revealed and considered indetail that there exist stable (metastable) entangled states at definitedistances between the atoms. That state is supported by a(quasi)stationary field bounded between the atoms. Also, acorrespondence is established between the lifetime and emissionspectrum, and possibilities for observing the effect are discussed.
|
|
