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971.
A. N. Makhinya M. A. Il’in I. A. Baidina P. E. Plyusnin N. I. Alferova D. P. Pishchur 《Journal of Structural Chemistry》2014,55(2):311-318
In treatment of trans-[Ru(NO)(NH3)4(OH)]Cl2 with concentrated sulfuric acid on heating trans-[Ru(NO)(NH3)4(SO4)](HSO4)·H2O (I) is obtained with a yield close to quantitative. In the interaction of the saturated solution of I with a saturated NaNO3 solution a trans-[Ru(NO)(NH3)4(SO4)]NO3·H2O (II) precipitate forms whose structure is determined by single crystal XRD: space group P212121, a = 6.8406(3) Å, b = 12.6581(5) Å, c = 13.3291(5) Å. A monodentately coordinated sulfate ion is in the trans-position to the nitroso group. Compound II is characterized by IR spectroscopy, powder XRD, and diffuse reflectance spectroscopy. The process of its thermolysis is studied; by differential scanning calorimetry the thermal effect of the dehydration reaction occurring on heating to 120°C (ΔH = 58.9 ± 1.5 kJ/mol) is estimated. The final product of the thermolysis of II is a mixture of Ru and RuO2. 相似文献
972.
973.
D. G. Cherkasov Z. V. Chepurina K. K. Il’in 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2014,88(4):612-615
The solubility of the components of the ternary water-pyridine-butyric acid system is studied by means of isothermal titration at 25.0°C under normal pressure. Nine nodes are plotted over the area of delayering using the Mertslin section method, and the compositions of the equilibrium liquid phases are determined graphically. It was found that there is a closed binodal curve with two critical points on the solubility diagram of the system; the distribution curve of pyridine between the equilibrium liquid phases demonstrates its preferential distribution into the organic phase. 相似文献
974.
P. Rajec L. Matel L. Drahošová V. Nemčovič 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(1):93-96
14C releases in the stack air of the NPPs V1 and V2, Jaslovske Bohunice was determined during the year 2004–2010. Radioactivity
concentration of 14C in the stack air was determined in the forms of inorganic 14CO2 and 14C
n
H
m
. The annual average activity concentration in the stacks air samples varies between 12 and 121 Bq m−3. NPP V1, starting with 45 Bq m−3 in 2005 is decreasing due to the shutting down of the reactors (the first reactor was shut down in December 2006 and the
second reactor in December 2008). The average value of radioactivity concentration for power unit V2 was 32 Bq m−3 in 2004 and reached the value of 102 Bq m−3 in the first-quarter of the 2010. The average normalized yearly discharge rates were between 0.39 and 0.64 TBq GWe−1 year−1 (2005–2008), NPP V1 and 0.19–0.61 TBq GWe−1 year−1 (2004–first-quarter 2010) for NPP V2, Jaslovske Bohunice. Most of the discharged 14C is in a hydrocarbon form, (95% for Jaslovske Bohunice NPP V2), but the CO2 fraction may reach 37% in the air stack for Jaslovske Bohunice V1. 相似文献
975.
Ľ. Vrtoch M. Pipíška M. Horník J. Augustín J. Lesný 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(3):853-862
In order to gain biosorbent that would have the ability to bind cesium ions from water solution effectively, potassium nickel
hexacyanoferrate(II) (KNiFC) was incorporated into the mushroom biomass of Agaricus bisporus. Cesium sorption by KNIFC-modified A. bisporus biosorbent was observed in batch system, using radiotracer technique using 137Cs radioisotope. Kinetic study showed that the cesium sorption was quite rapid and sorption equilibrium was attained within
1 h. Sorption kinetics of cesium was well described by pseudo-second order kinetics. Sorption equilibrium was the best described
by Freundlich isotherm and the distribution coefficient was at interval 7,662–159 cm3 g−1. Cesium sorption depended on initial pH of solution. Cesium sorption was very low at pH0 1.0–3.0. At initial pH 11.0, maximum sorption of cesium was found. Negative effect of monovalent (K+, Na+, NH4
+) and divalent (Ca2+, Mg2+) cations on cesium sorption was observed. Desorption experiments showed that 0.1 M potassium chloride is the most suitable
desorption agent but the complete desorption of cesium ions from KNiFC-modifed biosorbent was not achieved. 相似文献
976.
R. N. Rumyantsev A. A. Il’in A. P. Il’in I. V. Pazukhin 《Theoretical and Experimental Chemistry》2011,47(1):41-44
The influence of mechanical activation on the structure and catalytic activity of MoO3 was studied. It was established that as a result of mechanical treatment grinding, secondary aggregation of particles and
accumulation of materials from the grinding machine occurred. An increase in the catalytic activity was observed in the oxidation
of methanol to formaldehyde. 相似文献
977.
Micro–mesoporous materials combining the structural and sorption characteristics of a mesoporous molecular sieve (MMS) and
zeolite BEA were obtained by the “dry gel conversion” method – partial zeolitization of silica MMS SBA-15 in the presence
of tetraethylammonium hydroxide. The volume of the mesopores reaches 0.65 cm3/g, while that of the micropores is in the region of 0.1 cm3/g. The acidity of the obtained zeolitized materials differs from that of BEA; the total concentration of medium-strength
acid centers (maximum thermal desorption of ammonia at ~315 °C) amounts to 0.15 mmol/g. 相似文献
978.
In this study, affinity capillary electrophoresis (ACE) and quantum mechanical density functional theory (DFT) calculations were combined to investigate non-covalent binding interactions between the hexaarylbenzene-based receptor (R) and alkali metal ions, Rb(+) and Cs(+) , in methanol. The apparent binding (stability) constants (K(b) ) of the complexes of receptor R with alkali metal ions in the methanolic medium were determined by ACE from the dependence of effective electrophoretic mobility of the receptor R on the concentration of Rb(+) and Cs(+) ions in the BGE using a non-linear regression analysis. The receptor R formed relatively strong complexes both with rubidium (log K(b) =4.04±0.21) and cesium ions (log K(b) =3.72±0.22). The structural characteristics of the above alkali metal ion complexes with the receptor R were described by ab initio density functional theory calculations. These calculations have shown that the studied cations bind to the receptor R because they synergistically interact with the polar ethereal fence and with the central benzene ring via cation-π interaction. 相似文献
979.
Tanja Košutić Gulija Jelena Ivancic‐Jelecki Maja Šantak Dubravko Forcic 《Electrophoresis》2011,32(14):1852-1859
RNA viruses display the highest replication error rate in our biosphere, leading to highly diverse viral populations termed quasispecies. The gold standard method for detection and quantification of variants in a quasispecies is cloning and sequencing, but it is expensive, laborious and time consuming. Therefore, other mutation detection approaches, including SSCP, are often used. In this study, we demonstrate development and the usage of a CE‐SSCP method for quantification of two nearly identical viral variants in heterogenic population of a mumps virus strain and its comparison to RFLP‐CE‐fragment length analysis (RFLP‐CE‐FLA). Analyzed PCR fragments were of the same size (245 bp) with one difference in their nucleotide sequence. The limit of detection of both methods was at 5% of the minor variant. When PCR amplicons of the two variants were pooled, methods' results were very similar. On the contrary, the quantification results of samples in which variants were mixed prior to PCR showed substantial difference between the two methods. Our results indicate that although both methods can be used for detection and monitoring of a specific mutation within a viral population, caution should be taken when quantitative analysis of complex samples is based solely on results of one method. 相似文献
980.
Kvasnička F Copíková J Sevčík R Václavíková E Synytsya A Vaculová K Voldřich M 《Electrophoresis》2011,32(9):1090-1093
Phytic acid (PA) and lower inositolphosphates (InsP(n) ) is the main storage form of phosphorus in grains or seeds. The content of PA and InsP(n) in different varieties of barley was analyzed by capillary isotachophoresis and online-coupled capillary isotachophoresis with CZE. The electrolytes (in demineralized water) for the isotachophoretic analysis consisted of 10?mM HCl, 14?mM glycylglycine, and 0.1% 2-hydroxyethylcellulose (leading) and 10?mM citric acid (terminating). The optimized electrolytes for the online coupling isotachophoresis with zone electrophoresis analysis were mixtures of 5?mM HCl, 7?mM glycylglycine, and 0.1% 2-hydroxyethylcellulose (leading), 20?mM citric acid, 10?mM glycylglycine, and 0.1% 2-hydroxyethylcellulose (background) and 10?mM citric acid (terminating). PA and all studied InsP(n) were separated within 25?min and detected by a conductivity detector. Simple sample preparation (acidic extraction), sufficient sensitivity, speed of analysis, and low running cost are important attributes of the electrophoretic methods. The method was used for the determination of PA and InsP(n) in barley varieties within an ongoing research project. 相似文献