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81.
E. V. Mal’tseva A. A. Ivanov N. V. Yudina 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2009,83(11):1981-1985
The chemical composition of humic acids from brown coal (Aldrich) was determined by element analysis, 13C NMR spectroscopy, and potentiometric titration. The adsorption ability of humic acids with different biocides (cyproconasol,
propiconasol, tebuconasol, irgarol 1051, and DCOIT) was studied. The adsorption ability of a mixture of biocides in aqueous
solutions was higher than that of the individual components. The limiting concentration of humic acids at which adsorption
of biocides was maximum was determined. Adsorption constants were calculated by the Freundlich equation for each biocide in
aqueous solution. 相似文献
82.
A. I. Stash V. V. Levashova S. A. Lebedev Yu. G. Hoskov A. A. Mal’kov I. P. Romm 《Russian Journal of Coordination Chemistry》2009,35(2):136-141
The structures of the Pd4(SBu)4(OAc)4 (I) and Pd6 (SBu)12 (II) palladium clusters are determined by the X-ray diffraction method. For cluster I: a = 8.650(2), b = 12.314(2), c = 17.659(4) Å, α = 78.03(3)°, β = 86.71(2)°, γ = 78.13(3)°, V = 1800.8(7) Å3, ρcalcd = 1.878 g/cm3, space group P \(\bar 1\), Z = 4, N = 3403, R = 0.0468; for structure II: a = 10.748(2), b = 12.840(3), c = 15.233(3) Å, α = 65.31(3)°, β = 70.10(3)°, γ = 72.91(3)°, V = 1767.4(6) Å3, ρ calcd = 1.605 g/cm3, space group P \(\bar 1\), Z = 1, N = 3498, R = 0.0729. In cluster I, four Pd atoms form a planar cycle. The neighboring Pd atoms are bound by two acetate or two mercaptide bridges (Pd…Pd 2.95–3.23 Å, Pd…Pd angles 87.15°–92.85°). In cluster II, the Pd atoms form a planar six-membered cycle with Pd···Pd distances of 3.09–3.14 Å, the PdPdPd angles being 118.95°–120.80°. The Pd atoms are linked in pairs by two mercaptide bridges. The formation of clusters I and II in solution is proved by IR spectroscopy and calorimetry. Analogous clusters are formed in solution upon the reaction of palladium(II) diacetate with thiophenol. 相似文献
83.
The pentacoordinated terpyridine-phenanthroline zinc(II) complex motif, conceived along the HETTAP concept, allows the preparation of a set of multicomponent supramolecular dumbbell and clip assemblies from various bisterpyridines. All assemblies show a notable luminescence at 350-400 nm. The formation of dumbbell [Zn2(1b)2(2b)]4+ is convincingly demonstrated from the X-ray crystal structure analysis. Both dumbbell [Zn2(1b)2(2b)]4+ and clip [Zn2(1d)(2b)]4+ allow the monitoring of Hg2+ ions due to highly selective quenching of the emission that is driven by a Zn2+ --> Hg2+ exchange process, while the more-strained clip [Zn2(1d)(2c)]4+ does not undergo such metal exchange and does not show quenching of the luminescence. Consequently, these assemblies exhibit a highly selective response due solely to supramolecular effects. 相似文献
84.
Charge state distribution studies of pure and oxygen mixed krypton ECR plasma – signature of isotope anomaly and gas mixing effect 下载免费PDF全文
We report the charge state distributions of the pure, 25% and 50% oxygen mixed krypton plasma to shed more light on the understanding of the gas mixing and the isotope anomaly [A. G. Drentje, Rev. Sci. Instrum. 63 (1992) 2875 and Y Kawai, D Meyer, A Nadzeyka, U Wolters and K Wiesemann, Plasma Sources Sci. Technol. 10 (2001) 451] in the electron cyclotron resonance (ECR) plasmas. The krypton plasma was produced using a 10 GHz all‐permanent‐magnet ECR ion source. The intensities of the highly abundant four isotopes, viz. 82Kr (~11.58%), 83Kr (~11.49%), 84Kr (~57%) and 86Kr (17.3%) up to ~ +14 charge state have been measured by extracting the ions from the plasma and analysing them in the mass and the energy using a large acceptance analyzer‐cum‐switching dipole magnet. The influence of the oxygen gas mixing on the isotopic krypton ion intensities is clearly evidenced beyond +9 charge state. With and without oxygen mixing, the charge state distribution of the krypton ECR plasma shows the isotope anomaly with unusual trends. The anomaly in the intensities of the isotopes having quite closer natural abundance, viz. 82Kr, 86Kr and 83Kr, 86Kr is prominent, whereas the intensity ratio of 86Kr to 84Kr shows a weak signature of it. The isotope anomaly tends to disappear with increasing oxygen mixing in the plasma. The observed trends in the intensities of the krypton isotopes do not follow the prediction of linear Landau wave damping in the plasma. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
85.
Intercalation of octadecylamine into montmorillonite: molecular simulations and XRD analysis 总被引:2,自引:0,他引:2
Pospísil M Capková P Weiss Z Malác Z Simoník J 《Journal of colloid and interface science》2002,245(1):126-132
Intercalation of octadecylamine (ODAMIN) into Na montmorillonite based on the ion-dipole interaction was investigated using molecular mechanics and molecular dynamics simulations combined with X-ray powder diffraction. Molecular modeling revealed the interlayer structure of the ODAMIN-montmorillonite intercalate, the charge distribution on the host layer and guest species, and the energy characteristics, i.e., the total sublimation energy and it's individual contributions (electrostatic and Van der Waals). The present study showed the development of the interlayer structure, basal spacing, and exfoliation energy in dependence on the ODAMIN content. 相似文献
86.
M. L. Keshtov E. I. Mal’tsev A. M. Lopatin L. N. Nikitin D. V. Marochkin V. P. Perevalov P. V. Petrovskii A. R. Khokhlov 《Polymer Science Series B》2012,54(1-2):106-114
A number of new phenylated polyfluorenes with blue emission are synthesized via the Diels-Alder reaction in chloronaphthalene and supercritical carbon dioxide. It is shown that these polymers are thermally stable. A comparative analysis of their properties shows that a ??green?? solvent is a suitable alternative to organic solvents for obtaining phenyl-substituted polyfluorenes via the Diels-Alder reaction. 相似文献
87.
Recrystallization of natural chrysoberyl in multicomponent melts 总被引:1,自引:0,他引:1
N. A. Gromalova V. V. Mal’tsev G. I. Dorokhova N. I. Leonyuk V. S. Urusov 《Crystallography Reports》2012,57(4):603-608
Chrysoberyl and alexandrite crystals have been grown from solutions in melts based on the Li2CO3-MoO3, Bi2O3-MoO3, PbO-V2O5, Na2B4O7, and K2MoO4-MoO3 systems using natural alexandrite and chrysoberyl debris as the initial BeAl2O4 compound. An analysis of the morphology and homogeneity of the crystals grown has revealed the Bi2O3-MoO3 solvent to be the most appropriate. The optimal color characteristics (??quality?? of alexandrite effect) manifest themselves when adding about 5 mol % Cr2O3. The largest crystals (up to 10 mm in size) were obtained from a solution in melt based on PbO-V2O5 at a ratio of the crystal-forming component to the solvent of 9: 91 wt %; These characteristics, along with a relatively low operating temperature (970°C), give grounds to consider this type of solvent promising. 相似文献
88.
A. Yu. Bykov G. A. Razgonyaeva N. N. Mal’tseva K. Yu. Zhizhin N. T. Kuznetsov 《Russian Journal of Inorganic Chemistry》2012,57(4):471-473
A new method of synthesis of the B3H8− anion has been suggested. The method uses the reaction of some metal halides (CuCl, SnCl2, CrCl3, PbF2, PbCl2, PbBr2, and BiCl3) with sodium tetrahydroborate. It is characterized by high (up to quantitative) yields and simplicity of isolation of the
target products ((n-C4H9)4N)[B3H8] and Cs[B3H8]. 相似文献
89.
G. B. Deineka I. A. Mal’tsev I. I. Tupitsyn V. M. Shabaev G. Plunien 《Russian Journal of Physical Chemistry B, Focus on Physics》2012,6(2):224-228
Heavy ion collisions U92+-U91+(1s) at a 6 MeV incident particle energy per nucleon are considered. The wave function of the electron was determined by solving
the Dirac time-dependent equation in a central field, which is the sum of the potential of the target nucleus and the potential
of the incident nucleus taken in the monopole approximation. The Dirac equation was solved using the basis set of Hermitian
B-splines. The probabilities of remaining in the 1s target state were calculated as functions of the impact parameter. 相似文献
90.
Kovalev I. V. Mal’bakhova I. A. Vorob’ev A. M. Borisenko T. A. Popov M. P. Matvienko A. A. Titkov A. I. Nemudryi A. P. 《Russian Journal of Electrochemistry》2021,57(10):1019-1027
Russian Journal of Electrochemistry - Abstract—The results on the gas permeability of oxygen- and hydrogen-permeable microtube membranes are shown. For oxygen-permeable microtube membranes of... 相似文献