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41.
42.
The procedure for synthesis of hydrosols by hydrolysis of lanthanum nitrate was developed. The range of pH values was established corresponding to the maximum aggregation stability of sols. The photon-correlation spectroscopy was applied to determine the average hydrodynamic radius of sol particles, equal to 50 nm. The thresholds of fast coagulation of sol in the presence of sodium nitrate and sodium sulfate were determined. 相似文献
43.
N. N. Gavrilova M. A. Myachina D. V. Ardashev V. V. Nazarov V. V. Skudin 《Kinetics and Catalysis》2018,59(5):635-643
The methods of synthesis of composite membrane catalysts based on Mо2C and Al2O3 support by a sol–gel method were developed. The samples of membrane catalysts with different architectures were developed. The difference in the catalytic activity of membrane catalysts in carbon dioxide conversion of methane depending on the porous structure and morphology of the catalytic layer was studied. 相似文献
44.
Yu. V. Legostaeva L. R. Garifullina I. S. Nazarov G. Yu. Ishmuratov 《Russian Journal of Organic Chemistry》2018,54(1):146-148
Optically active isoniazid derivatives containing a cyclopropane or cyclobutane fragment have been synthesized by ozonolysis of (+)-Δ3-carene and (–)-α-pinene, followed by treatment of the ozonolysis products with isonicotinic acid hydrazide. 相似文献
45.
46.
A coagulation of nanodispersed TiO2 hydrosol mainly consisting of individual anatase nanocrystallites stabilized with HCl was studied. It was shown that only a part of a dispersed phase coagulates when a certain amount of HCl was added to the sol, and larger nanocrystallites are settled first. The procedure for the separation of the sol into the fractions of various dispersity was developed. 相似文献
47.
Nazarov PV Apanasovich VV Lutkovski VM Yatskou MM Koehorst RB Hemminga MA 《Journal of chemical information and computer sciences》2004,44(2):568-574
Simulation-based fitting has been applied to data analysis and parameter determination of complex experimental systems in many areas of chemistry and biophysics. However, this method is limited because of the time costs of the calculations. In this paper it is proposed to approximate and substitute a simulation model by an artificial neural network during the fitting procedure. Such a substitution significantly speeds up the parameter determination. This approach is tested on a model of fluorescence resonance energy transfer (FRET) within a system of site-directed fluorescence labeled M13 major coat protein mutants incorporated into a lipid bilayer. It is demonstrated that in our case the application of a trained artificial neural network for the substitution of the simulation model results in a significant gain in computing time by a factor of 5 x 10(4). Moreover, an artificial neural network produces a smooth approximation of the noisy results of a stochastic simulation. 相似文献
48.
Chlorocarbons were ionized through gas phase chemistry at ambient pressure in air and resultant ions were characterized using a micro-fabricated drift tube with differential mobility spectrometry (DMS). Positive and negative product ions were characterized simultaneously in a single drift tube equipped with a 3 mCi (63)Ni ion source at 50 degrees C and drift gas of air with 1 ppm moisture. Scans of compensation voltage for most chlorocarbons produced differential mobility spectra with Cl(-) as the sole product ion and a few chlorocarbons produced adduct ions, M (.-) Cl(-). Detection limits were approximately 20-80 pg for gas chromatography-DMS measurements. Chlorocarbons also yielded positive ions through chemical ionization in air and differential mobility spectra showed peaks with characteristic compensation voltages for each substance. Field dependence of mobility was determined for positive and negative ions of each substance and confirmed characteristic behavior for each ion. A DMS analyzer with a membrane inlet was used to continuously monitor effluent from columns of bentonite or synthetic silica beads to determine breakthrough volumes of individual chlorocarbons. These findings suggest a potential of DMS for monitoring subsurface environments either on site or perhaps in situ. 相似文献
49.
V. M. Nazarov M. V. Frontasyeva V. F. Peresedov V. P. Chinaeva T. M. Ostrovnaya S. F. Gundorina V. V. Nikonov 《Journal of Radioanalytical and Nuclear Chemistry》1995,191(2):229-238
Experience in the use of epithermal neutron activation analysis (ENAA) in the monitoring of atmospheric deposition by means of moss, lichens and pine needles is summarized. It is shown that 45 elements (Mg, K, Ca, Al, Cl, Sc, V, Cr, Mn, Fe, Co, Ni (using (n,p)-reaction), Zn, Cu, As, Se, Br, Rb, Sr, Zr, Mo, Ag, Sn, Sb, I, Cs, Ba, La, Ce, Nd, Sm, Eu, Gd, Tb, Tm, Yb, Lu, Hf, Ta, W, Au, Th and U, as well as Ir and Re in pine needles in the presence of anthropogenic pollution by the nickel mining plant) are reliably determined. Examples of the use of lichens, moss and pine needles as biomonitors of atmospheric deposition in Franz Josef Land the Kola peninsula and in the Tver region are given. 相似文献
50.
Nazarov A. M. Khursan S. L. Kalinichenko I. A. Ziganshina S. Kh. Komissarov V. D. 《Kinetics and Catalysis》2002,43(4):459-464
The rate constants of the reactions of diphenyl carbonyl oxide Ph2COO with a number of alcohols and water in acetonitrile, benzene, andn-decane solutions (295 K) were measured by flash photolysis. The rate constants vary over a range from 400 (triphenylmethanol in a MeCN solution) to 2.5 × 105 l mol–1 s–1 (adamantanol in a benzene solution). -Methoxydiphenylmethyl hydroperoxide is the reaction product of Ph2COO and MeOH. The absence of a kinetic isotope effect and the dependence of the logarithms of the rate constants on the first ionization potentials of alcohols are indicative of the formation of a C–O bond at the rate-limiting step of the reaction. 相似文献