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1.
B. L. Korsunskii G. V. Sitonina B. S. Fedorov F. I. Dubovitskii L. T. Eremenko 《Russian Chemical Bulletin》1989,38(4):710-713
| 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. |
2.
| 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. |
3.
| 1. | The adducts of N-benzenesulfonylbis(trifluoromethyl)ketenimine with either KF or KHF2 are formed when perfluoroisobutylene is reacted with the K salt of benzenesulfonamide. |
| 2. | N-Benzenesulfonylbis(trifluoromethyl)ketenimine was synthesized and some of its properties were studied. |
4.
| 1. | Using seven independent methods it was found that the concentration of the active centers on the surface of-Al2O3, which are responsible for the dehydration, is (9±1)×1017 centers/m2. The catalytically active centers are identical with adsorption centers. |
| 2. | A method of calculating the stochiometry, concentration, and thermodynamics of the surface association reactions has been developed. |
| 3. | The first reaction step proceeds according to the associative bimolecular substitution mechanism, with the formation of an associative intermediate compound. The association enthalpy and entropy have been calculated. |
5.
L. S. Isaeva G. I. Drogunova A. S. Peregudov D. N. Kravtsov 《Russian Chemical Bulletin》1988,37(1):153-157
| 1. | New cationic o-tolyl and o-fluorophenyl complexes of Ni containing Ph3P, MeCN, or THF ligands have been synthesized. |
| 2. | Reaction of these compounds with potassium carboxylates gave the novel o-tolyl and o-fluorophenylbis(triphenylphosphinyl)nickel carboxylates. |
| 3. | According to19F NMR data o-tolylbis(triphenylphosphinyl)nickel p-fluorobetizoate contained a highly polarized Ni-O bond. |
6.
| 1. | During shaping of titanium dioxide there are formed both paramagnetic (NO 3 2– , NO2, and NO) and nonparamagnetic (NO3–) forms of nitrogen oxides, stabilized in the TiO2 lattice. |
| 2. | In CO the radicals (NO 3 2– and NO2 are reduced to NO. |
| 3. | It is postulated that during shaping of TiO2 the NO2 molecules formed during oxidation of NH3 may be stabilized both on the lattice O2– and on Ti4+. |
7.
T. E. Kron V. S. Lopatina L. N. Morozova S. A. Lebedev L. S. Isaeva D. N. Kravtsov é. S. Petrov 《Russian Chemical Bulletin》1989,38(4):703-707
| 1. | The complexes ArNiXL2 and HNiXL2 (X is halide, L is tertiary phosphine) in the presence of zinc catalyze the condensation of bromobenzene with styrene (stilbene formation). |
| 2. | The yield of stilbene and 1,3-diphenylbutene, the dimerization product of styrene, in the presence of pyridine is lowered according to the substitution of phenyl groups on the phosphorus ligand L by alkyl (ethyl, cyclohexyl) groups. |
| 3. | Change of triphenylphosphine to phenylethylphosphines and tricyclohexylphosphine in the hydride complex HNi(X)(PR3)2, the catalytic activity of which falls in the order X=Cl–Br–>I–, favors the dimerization of styrene in the absence of pyridine. |
8.
A. Teies Gonsalo A. I. Donskikh V. N. Kulagin Yu. V. Moiseev G. M. Tseitlin 《Russian Chemical Bulletin》1976,25(5):1156-1158
| 1. | The hydrolysis rate of N-benzoylanthranilic acid was studied at a KOH concentration of 2.2–44.6% and a temperature of 25–95°. |
| 2. | The limiting step of the process is the reaction of the singly ionized form of the reagent with a molecule of water. |
| 3. | The equilibrium constant for the addition of hydroxyl ion to the carbonyl atom of the amido group of N-benzoylanthranilic acid is 267, and the true rate constant for the reaction of the ionized form with a molecule of H2O at 25° is 0.13 min–1. |
9.
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). |
10.
M. G. Chauser O. S. Anisimova L. S. Kol'tsova N. L. Zaichenko M. I. Cherkashin 《Russian Chemical Bulletin》1988,37(1):58-60
| 1. | A comparison of the results of studying the products of thermal polymerization of phenylacetylene by mass spectrometry and13C NMR showed that tetra-substituted cyclohexadiene and/or benzene rings are the terminal groups in polyphenylacetylene macromolecules. |
| 2. | The terminal cyclohexadiene rings are formed as a result of chain breaking by intramolecular cyclization of the propagating end. |
11.
The energy metabolism of a mammalian cell line grown in vitro was analyzed by substrate consumption rates and metabolic flux
measurements. The data allowed the determination of the relative importance of the pathways of glucose and glutamine metabolism
to the energy requirements of the cell. Changes in the substrate concentrations during culture contributed to the changing
catalytic activities of key enzymes, which were determined.
相似文献
| 1. | A murine B-lymphocyte hybridoma (PQXB1/2) was grown in batch culture to a maximum cell density of 1–2×106 cells/mL in 3–4 d. The intracellular protein content showed a maximum value during the exponential growth phase of 0.55 mg/106 cells. Glutamine was completely depleted, but glucose only partially depleted to 50% of its original concentration when the cells reached a stationary phase following exponential growth. |
| 2. | The specific rates of glutamine and glucose utilization varied during culture and showed maximal values at the midexponential phase of 2.4-nmol/min/106 cells and 4.3 nmol/min/106 cells, respectively. |
| 3. | A high proportion of glucose (96%) was metabolized by glycolysis, but only limited amounts by the pentose phosphate pathway (3.3%) and TCA cycle (0.21%). |
| 4. | The maximum catalytic activity of hexolinase approximates to the measured flux of glycolysis and is suggested as a rate-limiting step. In the stationary phase, the hexokinase activity reduced to 11% of its original value and may explain the reduced glucose utilization at this stage. |
| 5. | The maximal activities of two TCA cycle enzymes were well above the measured metabolic flux and are unlikely to pose regulatory barriers. However, the activity of pyruvate dehydrogenase was undetectable by spectrophotometric assay and explains the low level of flux of glycolytic metabolites into the TCA cycle. |
| 6. | A significant proportion of the glutamine (36%) utilized by the cells was completely oxidized to CO2. |
| 7. | The measured rate of glutamine transport into the cells approximated to the metabolic flux and is suggested as a rate-limiting step. |
| 8. | Glutamine metabolism is likely to occur via glutaminase and amino transaminase, which have significantly higher activities than glutamate dehydrogenase. |
| 9. | The calculated potential ATP production suggests that, overall, glutamine is the major contributor of cellular energy. However, at the midexponential phase, the energy contribution from the catabolism of the two substrates was finely balanced—glutamine (55%) and glucose (45%). |
12.
M. A. Dzyubina G. N. Kuz'mina B. I. Kolobkov A. I. Nekhaev 《Russian Chemical Bulletin》1988,37(10):2057-2062
| 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. |
13.
É. D. Filippova N. D. Mitrofanova L. I. Martynenko V. I. Spitsyn 《Russian Chemical Bulletin》1976,25(1):4-7
| 1. | Complexes of the REE, Y, and Sc with hydroxyethylethylenediaminetriacetic acid have been isolated in solid form. The hydrate compositions of the complexes have been determined. |
| 2. | The La and Pr complexes form hydrates of different compositions. The LnL hydrates form slightly nonisostructural groups in the series La-Lu. |
| 3. | According to thermographic analysis data, the hydrate water in the LnL·nH2O complexes of different hydrate compositions is not bonded with the same firmness. |
14.
I. A. Grigor'ev I. A. Kirilyuk V. F. Starichenko L. B. Volodarskii 《Russian Chemical Bulletin》1989,38(7):1488-1494
| 1. | Oxidation of 5-R1-2R2-4H-imidazole 1,3-dioxides in methanol with lead dioxide leads to the formation of stable nitroxyl and nitronylnitroxyl radicals with methoxy groups at the -carbon atom of the radical center. The ratio between these radicals is determined by the electronic character of the substituents at the 2- and 5-positions of the heterocyclic ring. |
| 2. | Oxidation of 4H-imidazole 1-oxides and 4H-imidazole 3-oxides in methanol with lead dioxide leads to the formation of iminonitroxyl radicals. |
| 3. | Oxidation of 2-unsubstituted 4H-imidazole 1,3-dioxides and 4H-imidazole 3-oxides in alcohols by lead or manganese dioxides leads to 2,2-dialkoxy-substituted stable nitroxyl radicals, which are derivatives of 3-imidazoline 3-oxide and 3-imidazoline. |
15.
R. A. Fridman G. A. Kliger E. I. Bogolepova Yu. V. Maksimov I. P. Suzdalev 《Russian Chemical Bulletin》1976,25(4):726-729
| 1. | The catalytic properties of iron nitride (Fe2N) and carbonitride (Fe2C0.29N0.71) in the reactions of amination and dehydrogenation of alcohols were compared. |
| 2. | In the course of the amination and dehydrogenation reactions on a nitride catalyst, there is an elution of part of the introduced nitrogen from the surface with the formation of the structure of the lower nitride. |
| 3. | For related structures of the nitride and carbonitride, a correlation was detected between the catalytic activity and the average magnetic moment of the iron atom in the alloy. |
16.
| 1. | The decomposition of hydroxyhydrotrioxides is described by a first order equation. The electron-donor substituents increase the stability of the hydrotrioxides. |
| 2. | There is a compensational effect for the preexponential factors and energies of activation of thermal overall decomposition of (CH3)2C(OH)OOOH in solvents CHCl3, CCl4. CH3CN, n-C6H14, (C2H5)2O and in C2H5OH-H2O mixtures. |
| 3. | The influence of the solvent on the rate constant of the overall decomposition of (CH3)2C(OH)OOOH is described for the range when the Koppel'-Pal'm equation holds. |
17.
| 1. | Adsorption isotherms of cyclopentane on commercial activated charcoal of the AG type obtained by vapor-gas activation of coal raw material were measured in the temperature interval from 298 to 343 K and equilibrium pressures from 10–1 to 1000 Pa. |
| 2. | The appearance of low-pressure hysteresis was detected under the given conditions. The position of the joining point of the hysteresis branches depends on temperature and shifts with a temperature increase into the region of lower pressures. |
| 3. | The phenomenon of low-pressure hysteresis in the given system is basically connected with reduced (slowed) penetration of the adsorbate into the pores of charcoal, which are close in size to the size of the adsorbate molecules. |
18.
K. K. Kalnin'sh 《Russian Chemical Bulletin》1988,37(9):1768-1773
| 1. | A new method of analysis of autocatalytic reactions was developed which permits determining the rate constants of noncatalytic and catalytic reaction pathways with the data from one kinetic curve. |
| 2. | The reverse reaction of acylation has an autocatalytic character. |
| 3. | In comparison to CHCl3, in CH3CN, all of the rate constants increase by 2–4 times, and the noncatalytic reaction pathways are more sensitive to the nature of the solvent. |
19.
V. F. Tarasov E. N. Step L. A. Margulis A. L. Buchachenko 《Russian Chemical Bulletin》1989,38(2):221-225
| 1. | The reaction of disproportionation of a geminal radical pair formed in photodissociation of desoxybenzoins is magnetic- and isotope-selective to the same degree as the recombination reaction. |
| 2. | The efficiency of separation of12C and13C isotopes based on the magnetic isotope effect decreases in the order desoxybenzoin, -methyldesoxybenzoin, and ,-dimethyldesoxybenzoin during photolysis, which is due to an increase in the probability of isotope-selective disproportionation of geminal radical pairs. |
20.
A. A. Bredikhin V. A. Kirillovich A. I. Andreeva I. A. Safin A. N. Vereshchagin 《Russian Chemical Bulletin》1989,38(1):58-63
| 1. | A specific geminal interaction in the OCCl triad, which is weakened in comparison to the corresponding ethers, appears in the mono--chloro esters RCOOCClR1R2. |
| 2. | All the mono--chloro esters exist in a synclinal conformation with respect to the O-Csp3 bond with a ClCOC(O) dihedral angle equal to 70–90°. |