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1.
B. A. Nabiev L. I. Lafer V. I. Yakerson A. M. Rubinshtein 《Russian Chemical Bulletin》1976,25(7):1398-1402
| 1. | CO2 interacts with the hydrogen forms of type Y zeolites, erionite, and mordenite without experiencing any loss in symmetry. |
| 2. | The adsorption of CO2 at 20°C on zeolites containing monovalent cations involves ion-dipole cation interaction in the case of A, X, and Y zeolites, erionite, and mordenite, and the formation of more stable carbonate structures in the case of the A, X, and Y zeolites. Transition between the bidentate coordinated carbonate structure and the carbonate ion proceeds through adsorbed forms of CO2 resulting from ion-dipole interactions. |
| 3. | The symmetry of stable carbonate structures established on the Ca forms of zeolites A, X, and Y can alter under the action of various adsorbates. |
2.
| 1. | The possibility of polymerizing 1,2-dimethylenecyclobutane with organolithium initiators has been demonstrated. The microstructure of the polymers obtained is determined by the nature of the solvent; in a hydrocarbon medium the 1,4-structural unit is mainly. formed, while in a polar solvent the 1,2-structural unit predominates. |
| 2. | The anionic copolymerization constants of 1,2-dimethylenecyclobutane with butadiene in hydrocarbon and polar media have been determined. |
3.
B. K. Nefedov N. S. Sergeeva T. V. Zueva E. M. Shutkina Ya. T. Eidus 《Russian Chemical Bulletin》1976,25(3):565-569
| 1. | Methanol, containing 10–20 mole % of CH3I, is carbonylated to methyl acetate in the presence of impregnated Eh-zeolite NaX catalyst at 230–250° and atmospheric pressure. |
| 2. | The specific (per gram of Rh) rate of methyl acetate formation is antibatic to the Rh content in the catalyst, it increases with increase in the methanol contact time, and shows little change in the range 230–250°. |
| 3. | The rate of forming the sole secondary product, namely dimethyl ether, decreases with increase in the amount of Rh and the methanol contact time. |
| 4. | CH2I is an astoichiometric component of the reaction. |
4.
| 1. | The kinetics of the Cannizzaro reaction of benzaldehyde in aqueous KOH solution have been studied spectrophotometrically, working at 25°C and at concentrations ranging from 19.1 to 37.9%. |
| 2. | Reaction proceeds through the formation of an activated complex consisting of the doubly ionized and the un-ionized forms of benzaldehyde and the hydroxide cation. |
| 3. | The spectrophotometric data and the kinetic data have been combined to give an estimate of the benzaldehyde ionization constant in aqueous KOH solution at 25°C. |
| 4. | Analysis of the kinetic data for benzaldehyde reduction by formaldehyde has shown the activated complex for this reaction to be composed of an un-ionized benzaldehyde molecule and a doubly ionized formaldehyde molecule, with or without participation of the hydroxide cation. |
5.
| 1. | The molecular-sieve properties of a number of synthetic and natural chabazites have been investigated. |
| 2. | Characteristic differences have been revealed in the molecular-sieve properties, thermal stability, and x-ray characteristics between the two groups of the zeolites studied. |
| 3. | A reversal of the molecular-sieve effect on passing from the calcium to the sodium-calcium forms of certain synthetic and natural chabazites has been observed. |
6.
I. E. Chlenov I. M. Petrova V. M. Shitkin V. A. Tartakovskii 《Russian Chemical Bulletin》1976,25(6):1347-1350
| 1. | The reaction of 6-nitro-2,9-dioxa-1-azabicyclo[4.3.0]nonane derivatives with alcohols and alcoholates leads to remplacement of the nitro group by the corresponding alkoxy group. |
| 2. | The reaction proceeds with either a complete (for the case of the alcoholates) or predominant (for the case of alcohols) inversion of the configuration at the substitution center. |
| 3. | The reaction proceeds via the intermediately formed bicyclic immonium cation. |
7.
Kh. M. Minachev E. S. Mortikov A. A. Masloboev N. F. Kononov N. V. Mirzabekova 《Russian Chemical Bulletin》1976,25(8):1682-1685
| 1. | Given the same conditions on interaction between benzene and ethylene on the zeolites with Ca and REE, essentially ethylbenzene is formed; on the zeolites with the Ni and Fe cations essentially a secondary butylbenzene is formed; and on the zeolites with the trivalent Cr, a high-molecular-weight polyethylene is formed. |
| 2. | A determining role of adsorption of one of the reactants in the change of the selectivity of zeolites with different cations has been demonstrated. |
8.
| 1. | The authors have studied the formation of electron and hole paramagnetic centers in gamma-irradiated magnesium hydroxide and oxide with various degrees of dehydration. |
| 2. | Rise in the temperature of preliminary heat treatment of the magnesium oxide causes an increase in the radiation-chemical yield of FS + centers and a decrease in that of V su – centers. |
| 3. | The thermal stability of paramagnetic centers in magnesium oxide increases as the hydroxyl group content decreases. |
9.
| 1. | An increase in the SiO2/Al2O3 ratio (x) in type Y zeolites through dealuminization with ethylenediaminetetraacetic acid leads to an increase in their catalytic activity during the alkylation of benzene with ethylene. |
| 2. | The properties of CaNaY zeolites of the same composition prepared from NaY obtained by hydrothermal synthesis and by dealuminization of samples with a small value of x are identical. |
| 3. | Carbon dioxide exerts an accelerating effect on the Ca forms of dealuminized type Y zeolites of various compositions and has no effect on the properties of NaY'. |
10.
Kh. M. Minachev V. V. Kharlamov V. I. Garanin D. B. Tagiev 《Russian Chemical Bulletin》1976,25(8):1615-1619
| 1. | Up to a certain point (55%), decationization of NaY zeolites reduces the activity of the zeolites in catalyzing the hydrogenation of 2-methyl-2-butene. Further decationization had no effect on the yield of saturated hydrocarbons. |
| 2. | Plotted as a function of the cation's electrostatic potential, the activity of MNaY zeolites in catalyzing the hydrogenation of 2-methyl-2-butene passes through a maximum. Minimum activity was observed with the NdNaY zeolite. |
| 3. | Experiments in an atmosphere of helium showed that saturated hydrocarbons, resulting from hydrogen redistribution, are frequently formed in the course of reactions on decationized and polyvalent cationic forms of the Y zeolite. |
11.
| 1. | Replacing Na+ ions by Ca2+in zeolites leads to a significant shift of the region in which thermally stimulated polarographic [TSD] current peaks appear toward higher temperatures. |
| 2. | Reducing the cation content in zeolites leads to a decrease in the intensity of TSD currents. |
| 3. | The data obtained-can be explained by the differences in the distributions of the cations between different crystallographic positions in the zeolite lattices. |
12.
T. M. Guliev A. A. Isirikyan D. I. Mirzai V. V. Serpinskii 《Russian Chemical Bulletin》1988,37(12):2576-2578
| 1. | Stilbite and heulandite begin to undergo sintering upon heating in vacuum at 200 ± 5°C and undergo about 80% dehydration. |
| 2. | The rehydration energy (heat of immersion in water) of stilbite and heulandite reach maximal values of 350 ± 15 and 215 ± 15 J/g after pumping at 230 ± 20 and 200 ± 20°C, respectively. Maximum half-width values are reached at 250 and 300°C, respectively. |
| 3. | The maximal integral mean-molar heats of adsorption of water vapor on stilbite and heulandite after pumping at 230 and 200°C, respectively, are 76 ± 3 and 69 ± 3 kJ/mole. |
13.
N. V. Zakatova D. R. Minkhadzhidinova M. A. Nadzhafova R. F. D'yachkovskaya N. P. Koaovalova V. A. Sharpatyi 《Russian Chemical Bulletin》1976,25(2):434-436
| 1. | We determined the reactivity of some nitrogen bases, and of a number of amino acids and bis-(diazoacetyl)alkyl derivatives toward the electron at 77°K. |
| 2. | The effect of the pH at 77°K as established on the yield of the deamination process and the reactivity of the studied amino acids toward the electron. |
| 3. | It was found that the yield for the deamination of glutamic acid is increased in the presence of inositol (acceptor of OH radicals). |
14.
Kh. M. Minachev Ya. I. Isakov V. P. Kalinin Yu. S. Akhmetov 《Russian Chemical Bulletin》1976,25(5):1041-1048
| 1. | The catalytic properties of the Ni forms of various types of synthetic zeolites in the reaction of benzene with ethylene are determined by their structure, composition, and conditions under which they are used. |
| 2. | The NiNaA zeolites accelerate only the dimerization of C2H4, and are inactive in the alkylation of C6H6 with olefins. From benzene and ethylene it is possible to obtain on NiX and NiY either predominantly sec-butylbenzene (SBB) (selectivity 80–86%) or SBB and butenes in approximately equal amounts. |
15.
| 1. | A study was made of the irreversible heat inactivation of free trypsin, and of trypsin in the complex with poly-4(5)-vinylimidazole, in aqueous solution, at pH 6.1, in the temperature range 33–50°. |
| 2. | The inactivation rate of trypsin decreases in the presence of the polymer, and its activation enthalpy increases when compared with the values of these parameters for free trypsin. |
16.
| 1. | The authors suggest a model to explain the axial symmetry of the hole center V– in magnesium oxide. |
| 2. | Using the model they consider the possible alternatives for localization of the hydroxyl groups of the hole center. |
| 3. | In analytic form, they express the values of the g factors for the V– center in terms of the parameters of the method of molecular orbits. The experimental values of the g factors can be explained if we assume localization of one or two hydroxyl groups in the first or second layer from the O– radical ion in the MgO lattice. |
17.
V. I. Bregadze A. Ya. Usyatinskii V. A. Antonovich N. N. Godovikov 《Russian Chemical Bulletin》1988,37(3):570-573
| 1. | Carboranyl derivatives of aluminum, gallium, and indium, containing a Ccarb-M bond, were obtained. |
| 2. | Carboranes react with trimethylgallium etherate in the presence of tetramethyl-ethylenediamine to give gallium-containing dicarbaundecaborate ions. |
18.
| 1. | It was found that trivalent rhenium chloride has a high activity in the hydrogenation of the C=C bonds in cyclohexene, the pyridine ring, and thiophene at 200–270°, a hydrogen pressure of 130–140 atm, and a reaction time of 3 h. |
| 2. | Rhenium(III) chloride has a higher activity than rhenium heptasulfide in reducing the C=C bond in cyclohexane and the pyridine ring |
19.
R. B. Akhverdiev I. A. Timakov R. G. Sarmurzina V. I. Yakerson M. I. Rustamov M. K. Guseinova Sh. K. Seitzhanova 《Russian Chemical Bulletin》1989,38(3):455-458
| 1. | Aluminum hydroxide and oxide supports, obtained by interaction with water of aluminum activated by indium or gallium, are multiphasic systems containing in the first case PB, BR, and In, and in the second, -Al2O3, In2O3, and In. |
| 2. | The presence of Co and Ni as alloys with activated aluminum determined the x-ray amorphous character of the Co- and Ni-containing phases at all stages, including the thermal treatment of the hydroxide and oxide systems. In the case of the copper alloy, only with thermal treatment does the partial crystallization of the CuO phase occur. |
| 3. | Introduction of the Co, Ni, and Cu ions into the aluminum oxide or hydroxide matrices, obtained from activated aluminum, show a definite effect on the formation of the Co3O4, CoAl2O4, and NiAl2O4 phases after thermal treatment. For the Cu-containing catalysts, the Cu2O and CuO phases are formed even before thermal treatment. |
20.
B. A. Arbuzov S. G. Vul'fson G. G. Butenko O. A. Samarina A. B. Teitel'baum A. N. Vereshchagin 《Russian Chemical Bulletin》1976,25(1):75-81
| 1. | The ellipsoids of polarizability of dimethylsulfone, sulfuryl chloride, and methanesulfonyl chloride were determined, and the nonadditivity of the parameters of the bonds in the sulfonyl chloride group was demonstrated. |
| 2. | Substituted methane sulfonyl chloride exist in gauche conformations. |
| 3. | In benzenesulfonyl chloride and a series of its para-substituted derivatives, the aryls are situated in the C-S-Cl plane; the para-nitro group induces a 35° rotation. |