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1.
Sergey Sigalov Mikhael D. Levi Gregory Salitra Doron Aurbach Alar Jänes Enn Lust Ion C. Halalay 《Carbon》2012,50(10):3957-3960
A TiC-derived carbon (TiC-CDC) was prepared, and the adsorption of large hexacyanocobaltate and tetrabutylammonium ions of approximately same size was examined on this carbon. While selectively absorbing these large ions, it rejects smaller chloride and ammonium ions in mixed electrolyte solutions. The result demonstrates the important role of electrostatic repulsive forces, space-efficient charge packing and hydrophobic ion interactions with the pore walls of TiC-CDC, similar to what is known for a variety of biological membranes. 相似文献
2.
Pavel Grigorenko Ando Saabas Enn Tyugu 《Electronic Notes in Theoretical Computer Science》2005,141(4):137
A compiler-compiler for visual languages is presented. It has been designed as a framework for building visual programming environments that translate schemas into textual representation as well as into programs representing the deep meaning of schemas. The deep semantics is implemented by applying attribute grammars to schema languages; attribute dependencies are implemented as methods of Java classes. Unlike compiler-compilers of textual languages, a large part of the framework is needed for support of interactive usage of a visual language. 相似文献
3.
Micro- and mesoporous carbide-derived carbon (CDC) was synthesised from molybdenum carbide (Mo2C) powder by gas phase chlorination in the temperature range from 400 to 1200 °C. Analysis of XRD results show that C(Mo2C), chlorinated at 1200 °C, consist mainly on graphitic crystallites of mean size, La = 9 nm and Lc = 7.5 nm. The first-order Raman spectra showed the graphite-like absorption peak at ∼1587 cm−1 and the disorder-induced (D) peak at ∼1348 cm−1. The low-temperature N2 adsorption experiments were performed and a specific surface area up to 1855 m2 g−1 and total pore volume up to 1.399 cm3 g−1 were obtained. Sorption measurements showed the presence of both micro- and mesopores after chlorination at 400-900 °C and only mesopores after chlorination at 1000°-1200 °C. Stepwise formation of micro- and mesopores was achieved and the peak pore size can be shifted from 0.8 nm up to 4 nm by increasing the chlorination temperature. 相似文献
4.
Impedance spectroscopy and in situ STM methods have been used for investigation of the camphor and 2,2′-bipyridine (2,2′-BP) adsorption at the electrochemically polished Bi(1 1 1) electrode from weakly acidified Na2SO4 supporting electrolyte solution. The influence of electrode potential on the adsorption kinetics of camphor and 2,2′-BP on Bi(1 1 1) has been demonstrated. In the region of maximal adsorption, i.e. capacitance pit in the differential capacitance versus electrode potential curve, the heterogeneous adsorption and diffusion steps are the rate determining stages for camphor and 2,2′-BP adsorption at the Bi(1 1 1) electrode. It was found that for camphor | Bi(1 1 1) interface the stable adsorbate adlayer detectable by using the in situ STM method has been observed only at the positively charged electrode surface, where the weak co-adsorption of SO42− anions and camphor molecules is possible. At the weakly negatively charged Bi(1 1 1) electrode surface there are only physically adsorbed camphor molecules forming the compact adsorption layer. The in situ STM data in a good agreement with impedance data indicate that a very well detectable 2,2′-BP adsorption layer is formed at Bi(1 1 1) electrode in the wide region of charge densities around the zero charge potential. 相似文献
5.
CuInSe2 thin films were grown onto ITO surface by electrodeposition and annealed in the hydrogen atmosphere at 400 °C. The influence of traditional chemical etching (KCN etchant) and electrochemical etching at various potentials and values of solution pH (0.8-13) on the surface composition and morphology was studied using the EDX and SEM methods. The mechanism of CuInSe2 decomposition at various pH values was examined by cycling voltammetry. The influence of chemical and electrochemical etchings on electrical and optical characteristics of thin films was analyzed. 相似文献
6.
K. Timmo M. Altosaar J. Raudoja E. Mellikov T. Varema M. Danilson M. Grossberg 《Thin solid films》2007,515(15):5887-5890
The effect of sodium doping to the electrical and photoluminescence properties of CuInSe2 monograin powders was studied. Sodium was added in controlled amounts from 5 × 1016 cm− 3 to 1 × 1020 cm− 3. The photoluminescence spectra of Na-doped stoichiometric CuInSe2 powders had two bands with peak positions at 0.97 and 0.99 eV. The photoluminescence bands showed the shift of peak positions depending on the Na doping level. Peak positions with maximum energy were observed if added sodium concentration was 1 × 1019 cm− 3. This material had the highest carrier concentration 2 × 1017 cm− 3. In the case of stoichiometric CuInSe2 (Cu:In:Se = 25.7:25.3:49.0), Na doping at concentrations of 3 × 1017 cm− 3 and higher avoided the precipitation of Cu-Se phase. Solar cells output parameters were dependent on the Na doping level. Sodium concentration 3 × 1018 cm− 3 resulted in the best open-circuit voltage. 相似文献
7.
Margus Friedenthal Kairit Eha Anu Viitak Ave Lukas Enn Siimer 《Innovative Food Science and Emerging Technologies》2000,1(4):275-279
Thermal stability, by means of air drying a furcellaran powder, and its impact on gel strength and cation mobility were studied. Halogen heating in the temperature range 90–115°C for 15 min resulted in loss on drying (LD, %). These results can be described by polynom LD=−9.583+2.989τ−0.249τ2+0.00729τ3+0.1034t (R2=0.9976), indicating a gradual decomposition of carbohydrates. Air-drying induced a decrease in gel strength and the partial removal of potassium, calcium and sodium ions from the matrix. Air drying above 115°C yielded a remarkable destruction of polysaccharides with a total collapse in gelling power. 相似文献
8.
Enn Tyugu 《Theoretical computer science》1991,90(1):185-198
This paper describes dataflow schemas which include higher order objects as the input data of processing nodes. It is demonstrated that higher order dataflow can be described by constructive propositional logic. Rules for safe computations on higher order dataflow schemas are presented and their implementation in hardware is discussed. 相似文献
9.
N. Revathi S. Bereznev J. Iljina M. Safonova E. Mellikov O. Volobujeva 《Journal of Materials Science: Materials in Electronics》2013,24(12):4739-4744
Recent interests focus on tin mono sulphide as a potential candidate for an absorber layer in heterojunction solar cells. In the present investigation, SnS thin films have been deposited onto different substrates such as glass, ITO and Mo-coated glass substrate by thermal evaporation method. The compositional, microstructural and photoelectrochemical properties of the SnS films were analyzed depending upon the chemical nature of the substrates used. The SnS layers were polycrystalline with Herzbergite orthorhombic structure on all three substrates and had nearly stoichiometric elemental composition with a Sn/S ratio of ~1.01. The films grown on ITO and Mo-coated glass substrates exhibit (040) as preferred orientation whereas the films deposited on glass showed (111) plane as predominant. The layers were densely packed and well adherent to the substrate surface. The Raman spectra showed bands at 64, 163, 189 and 219 cm?1, which corresponds to the single phase (SnS) composition of films. p-type conductivity of all the deposited films were determined by the photoresponse studies. The highest photoresponse for the films on the ITO substrate indicates their appropriateness for the solar cell application. 相似文献
10.
Commercial nanoporous carbon RP-20 was activated with water vapor in the temperature range from 950 °C to 1150 °C. The XRD analysis was carried out on nanoporous carbon powder samples to investigate the structural changes (graphitisation) in modified carbon that occurred at activation temperatures T ? 1150 °C. The first-order Raman spectra showed the absorption peak at 1582 cm−1 and the disorder (D) peak at 1350 cm−1. The low-temperature N2 adsorption experiments were performed at −196 °C and a specific surface area up to 2240 m2g−1 for carbon activated at T = 1050 °C was measured. The cell capacitance for two electrode activated nanoporous carbon system advanced up to 60 F g−1 giving the specific capacitance ∼240 F g−1 to one electrode nanoporous carbon ∣1.2 M (C2H5)3CH3NBF4 + acetonitrile solution interface. A very wide region of ideal polarisability for two electrode system (∼3.2 V) was achieved. The low frequency limiting specific capacitance very weakly increases with the rise of specific area explained by the mass transfer limitations in the nanoporous carbon electrodes. The electrochemical characteristics obtained show that some of these materials under discussion can be used for compilation of high energy density and power density non-aqueous electrolyte supercapacitors with higher power densities than aqueous supercapacitors. 相似文献