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41.
A. V. Konstantinov R. V. Shafigulin M. M. Il’in V. A. Davankov A. V. Bulanova P. P. Purygin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2013,87(6):1039-1042
The results from chromatographic analysis of biologically active isatin derivatives on hyper-crosslinked polystyrene (HCLPS) and silica gel modified by octadecyl groups (SilC18) are presented. The constants of distribution of sorbates between a mobile phase and the investigated sorbents (K x ) and the changes in the standard differential molar Gibbs energies of adsorption $(\Delta _a \bar G^\circ )$ are calculated, along with the chromatographic retention-physicochemical property of sorbate dependences. It is found that the equations describing these dependences have high forecasting ability with respect to the values of retention factors of the investigated sorbates. 相似文献
42.
K. K. Il’in D. G. Cherkasov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2013,87(4):598-602
Phase equilibria and critical phenomena in a cesium nitrate-water-triethylamine system in which the constituent binary liquid system is stratified at the lower critical solution temperature (LCST) is studied in a range of 5–25°C by the visual polythermal method. It is found that introducing cesium nitrate into the water-triethylamine system leads to a slight reduction in the LCST (from 18.3 to 16.3°C) and to a decrease in the mutual solubility of the components. The distribution coefficients of triethylamine between aqueous and the organic phases of the monotectic state at different temperatures are calculated. It is found that the salting-out of triethylamine from aqueous solutions by cesium nitrate increases with rising temperature. The results of the salting-out effect of sodium, potassium, and cesium nitrates on a water-triethylamine binary system are compared. 相似文献
43.
Il’in A. V. Gubaev A. F. Zarzhitskaya E. V. Islamov D. R. Kuchaev E. S. 《Russian Journal of General Chemistry》2022,92(7):1190-1198
Russian Journal of General Chemistry - An efficient method for the phosphine-catalyzed bisaddition of P(O)H compounds and cyclic imides to divinyl sulfone has been developed. The reaction proceeds... 相似文献
44.
Ayten Behçet Aydın Aktaş Yetkin Gök Rüya Kaya Parham Taslimi İlhami Gülçin 《Journal of heterocyclic chemistry》2021,58(2):603-611
Herein, novel silver-based N-heterocyclic carbene (NHC) complexes bearing 2-(4-hydroxyphenyl)ethyl group were synthesized. Novel Ag(I)NHC complexes were synthesized from the 2-(4-hydroxyphenyl)ethyl-substituted benzimidazolium salts and silver oxide via in situ deprotonation method. The successful formation of all Ag(I)NHC complexes was proved by using 1H NMR, 13C NMR, FTIR spectroscopy, and elemental analysis techniques. In addition, their inhibitory effects have been investigated of these substances on acetylcholinesterase (AChE), α-glycosidase (α-Gly), human carbonic anhydrase I (hCA I), and human carbonic anhydrase II (hCA II) enzymes. It has been seen that all compounds have a better ability to inhibit compared with existing tried inhibitors. Among these, the best inhibitor against AChE enzyme is 1g (Ki : 9.54 ± 0.98 μM and IC50 : 17.40), and against α-Gly, 1c showed the highest effect (Ki 3.09 ± 0.36 μM and IC50 7.91). The best inhibitor against hCA I and hCA II enzymes are 1c and 1g compounds. For hCA I and hCA II, IC50 values were calculated as 17.85 and 9.06 μM and Ki values were measured as 5.45 ± 2.02 and 8.99 ± 2.02 μM, respectively. 相似文献
45.
46.
I. Paradela Pérez M. Groth M. Wischmeier D. Coster D. Brida P. David D. Silvagni M. Faitsch the ASDEX-Upgrade Team the EUROfusion MST Team 《等离子体物理论文集》2020,60(5-6):e201900166
SOLPS-ITER L-mode-like simulations with the full set of currents and drift velocities activated, and fluid neutrals have been carried out to interpret experimental results obtained in AUG. Drifts are critical to quantitatively reproduce the experimental results; however, simulations without drifts can also reproduce some trends qualitatively. The magnitude and dependence of the peak heat flux onto both targets on the upstream collisionality are, in general, in quantitative agreement within uncertainties with infrared thermography measurements in favourable field direction. The onset of power detachment is observed. In unfavourable toroidal field direction, a more symmetrical inner/outer target solution with regards to the power distribution is predicted, in agreement with experimental observations. However, also in unfavourable toroidal field direction, insufficient power is dissipated in the simulations and therefore qpeak, inn is overpredicted by up to a factor of 4 and qpeak, out by up to a factor of 1.5. The largest contribution to the sources due to radial transport in the energy balance equation is the radial divergence of the energy flux due to VE × B. 相似文献
47.
LI Cun-man XIAO Yuan-sheng XUE Xing-ya FENG Jia-tao ZHANG Xiu-li LIANG Xin-miao . Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian P. R. China . Hebei Research Centre of Analysis Testing Hebei University of Science Technology Shijiazhuang 《高等学校化学研究》2011,(3):392-396
An efficient preparative method was successfully developed for isolation and purification of unstable components from medicinal plant extracts, using a combined method of preparative high performance liquid chro-matography(HPLC) and solid-phase extraction(SPE). The aim of this study was to obtain an effective method with high preparative efficiency and importantly to avoid the transformation of unstable compounds. The preparative HPLC system was based on an LC/MS controlled four-channel autopurification sys... 相似文献
48.
L. Yu. Dolgikh I. L. Stolyarchuk P. E. Strizhak A. V. Shvets V. G. Il’in 《Theoretical and Experimental Chemistry》2006,42(1):37-42
The dependence of the activity and selectivity of ion-exchanged forms of zeolite X with incorporated cesium process in alkylation
of toluene with methanol in the side chain on the nature of the ion-exchanged cations (Na+, Cs+, Mg2+, Zn2+) has been established. It is shown that introduction of Mg2+ and Zn2+ in combination with Cs2CO3 significantly increased the yields of ethylbenzene and styrene in comparison with their yields on alkali forms of zeolite
X.
__________
Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 42, No. 1, pp. 33–38, January–February, 2006. 相似文献
49.
The transient absorption spectra of triphenylamine (TPA) in various solvents have beeninvestigated by the methods of nanosecond laser photolysis. The lifetimes of TPA were meas-ured. In hexane and ethanol, the transient absorptions of triplet state and triplet excimer ofTPA were observed. However, the transient absorptions of the TPA cation radical was alsoobserved in acetonitrile besides that of the triplet TPA monomer and excimer. According tothe experimental facts, the transient photophysical mechanism of TPA in various solvents hasbeen proposed. 相似文献
50.
The construction of an automated adiabatic calorimeter for heat capacity measurement ofsolids in the temperature range of 25- 90K is described in detail. The sample vessel of thecalorimeter has thin radial vanes which make no contact with its inner wall and are distrib-uted evenly, thus greatly improving the internal thermal equilibration of the vessel. Theprecision of temperature control for the adiabatic shields and electrical leads of the calori-metric system are heightened to a great extent by using the high precision ACD- 79 modeladiabatic controller specially developed by us for this purpose. Measurements of the heatcapacities of high purity α-Al_2O_3, one of the internationally-accepted standard referencematerials, agree with those of the National Bureau of Standards (NBS), USA within ±0.3%,demonstrating the reliability of this apparatus. 相似文献