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1.
1.  Dithiophosphoric acids are either not catalysts or only act as moderate catalysts as a function of the structure in reactions of decomposition of CHP.
2.  The real catalyst of decomposition of CHP in the presence of dithiophosphoric acids is the sulfuric acid formed during the oxidation of the dithiophosphoric acids, or the combination of the sulfuric acid with phosphours-containing acids.
3.  Slow and fast stages of kinetic decomposition of CHP were detected, and the kinetic parameters of the fast stage were determined.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 34–41, January, 1989.  相似文献   

2.
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).
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3.
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.
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4.
1.  Flames resulting from chain NCl3 decomposition are propagated through NCl3 + He mixtures lying outside the autoignition region.
2.  The fact that these are essentially isothermal flames is an indication of the important role of positive chain interaction in this process.
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5.
1.  The thermal decomposition of N,N-dinitroamines is homogeneous and unimolecular in the gas phase. The limiting step of the process is the rupture of the N-NO2 bond.
2.  The activation parameters of the process imply that the dinitroamine group is more reactive than the mononitroamine group in thermal decomposition. The energy of dissociation of the N-NO2 bond in dinitroamines is 42 kJ/mole less than in mononitroamines.
3.  Nitrogen dioxide and acetaldehyde do not influence the kinetics of thermal decomposition of dinitroamines due to their high reactivity.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 790–793, April, 1989.  相似文献   

6.
1.  Depending on the nature of the substituent in the 2 position, l-fluoro-l-(-hydrohexafluoroisopropyl)ethylenes are dehydrofluorinated to either allenes or 1,3-dienes.
2.  It was shown that allylic substitution is possible in the reactions of perfluoroisobutylene with carbanions; the mutual transformations of the allyl and vinyl isomers were studied.
3.  The perfluoroalkenylation product was obtained when perfluoroisobutylene is reacted with ketene acetal.
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7.
1.  The dipole moments of the two kinds of C-O bonds in acetals and their analogs are not identical.
2.  In formal molecules and the dimethylketal of acetone the C-O-C-O -C chains have gauche-gauche conformation, with the methyl groups lying on different sides of the O-C-O plane.
3.  The dimethylketal of tetrachlorocyclopentadienone is represented by a mixture of trans-gauche and gauche-gauche conformers.
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8.
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.
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9.
1.  N-Ethyl and N-isopropyl-3-piperidones were synthesized and the stereochemistry of their reduction was studied.
2.  The dependenceof stereochemistryof a series of reactions at the carbonyl center on bulk of the substituent on nitrogen was established.
3.  Pure a- and e-epimers of N-ethyl- and N-isopropyl-3-piperidols were separated.
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10.
1.  In NaA zeolite a homocharge is formed by charges deposited on the surface of the zeolite from the gas gap between the electrode and the specimen.
2.  The existence of thermoelectret effects has been found in the systems NaA-zeolite -air, NaA-helium, NaA-nitrogen, and NaA-oxygen.
3.  The thermoelectret effects are caused by both the accumulation of charges in the specimen and the adsorption of molecules in the electric field.
4.  A low mobility has been noted for adsorbed molecules in the electret state of the system.
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11.
1.  Oxidation of o-organosilyl-substituted phenols with potassium ferricyanide in an alkaline medium in an oxygen atmosphere led to the formation of siloxydiphenyls and bis(l-R2-3-R1-5-R3-2,5-cyclohexadien-4-one) peroxides.
2.  The silyl-substituted peroxides were isolated preparatively. Their thermal decomposition occurred by a homolytic mechanism with cleavage of the O-O bond.
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12.
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.
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13.
1.  For the first time a diastereomerically enriched acyclic NH-dialkoxyamine with asymmetric nitrogen atom in the NH group was obtained.
2.  By low-temperature PMR spectra the diastereomers of a 1,1-dialkoxyurea with asymmetric amid enitrogen atom were observed.
For previous communication, see [1].  相似文献   

14.
1.  Indium atoms have been obtained in aqueous solutions of univalent indium by pulse radiolysis.
2.  In0 reacts with In+ to form the dimer In 2 + .
3.  The optical characteristics of these particles, the rate constants for their formation and loss, as well as the oxidation-reduction potentials have been determined.
We thank A. G. Egorova for providing the InBr salt.  相似文献   

15.
1.  Rhodium complexes [RhCl(COD)]2, RhCl(PPh3)3, and RhCl3 immobilized on silica gel modified by aminophosphine groups catalyze the transfer of hydrogen from 2-propanol to cyclohexanone, styrene, and 2-cyclohexenone and the isomerization of allylbenzene in an argon atmosphere.
2.  The reduction of cyclohexanone to cyclohexanol is promoted by alkali. The reaction rate is proportional to the amount of catalyst, 2-propanol concentration, and cyclohexanone. The reaction rate decreases at high ketone concentrations.
3.  Styrene is reduced to ethylbenzene extremely slowly. Under these conditions, allylbenzene is not reduced, but rather undergoes isomerization with the predominant formation of trans-propenylbenzene.
4.  The reduction of 2-cyclohexenone to cyclohexanol occurs by the initial reduction of the C=C bond and the subsequent reduction of the C=O group.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1223–1228, June, 1988.  相似文献   

16.
1.  The activation energy for the thermal decomposition of complexes with Fe2(CO)6S2 frameworks amounts to 103–144 kJ/mole.
2.  Decarbonylation and splitting off of the hydrocarbon part of the molecule is the general pattern of behavior of iron carbonyl compounds with sulfur ligands on heating and under electron bombardment.
3.  In complexes containing a norbornadiene fragment, a reverse Diels-Alder reaction takes place under electron bombardment, in addition to splitting off of norbornadiene.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2286–2292, October, 1988.  相似文献   

17.
1.  A number of compounds of the ArSrl class were synthesized in THF solution, and the complexes of these compounds with THF were isolated.
2.  Some of the reactions of these compounds were studied.
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18.
To mitigate CO2 discharged from thermal power plants, studies on CO2 fixation by the photosynthesis of microalgae using actual exhaust gas have been carried out. The results are as follows.
1.  A method is proposed for evaluating the maximum photosynthesis rate in the raceway cultivator using only the algal physical properties;
2.  Outdoor cultivation tests taking actual flue gas were performed with no trouble or break throughout 1 yr using the strain collected in the test;
3.  The produced microalgae is effective as solid fuel; and
4.  The feasibility studies of this system were performed. The system required large land area, but the area is smaller than that required for other biomass systems, such as tree farms.
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19.
1.  An efficient method of aziridine dimer synthesis is presented involving reaction of aziridine with esters of strong organic acids followed by alkaline hydrolysis of the resultant N-acyl derivatives.
2.  New N-acyl and carbamoyl derivatives of aziridine dimer and trimer were synthesized.
3.  Linear and branched isomers of aziridine tetramer and also diastereomers of 2-methylaziridine dimer were isolated and characterized.
4.  An efficient regiospecific synthesis of 2,2-dimethylaziridine dimer and trimer was developed.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2566–2575, November, 1988.  相似文献   

20.
1.  Study has been made of the kinetics of the-elimination of alcohol from 3-carbethoxy-4-ethoxy-2-pentanone in benzene and under the catalytic action of acetic acid.
2.  This reaction involves formation of a complex between substrate and acetic acid.
3.  The equilibrium constant for the reaction of forming the complex between substrate and acetic acid, and the rate constant for complex formation, have both been determined.
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