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1.
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.
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2.
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.
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3.
1.  A method has been developed for the intercalation of solid substances from solutions in organic solvents into graphite fluoride C2Fx.
2.  Molecules of inserted paramagnetic copper complexes and nitroxyl radicals assume oriented positions between the structural layers in graphite fluoride.
3.  The planes of molecules of bis-chelate Cu(II) complexes with acetylacetone, o-hydroxyquinoline, and phenylsalicylaldimine were determined to lie parallel to the C2Fx planes.
4.  A method has also been suggested for the preparation of samples from C2Fx·yA compounds with a higher degree of texturizing (more nearly complete orientation) than can be achieved by pelletizing.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 272–276, February, 1988.  相似文献   

4.
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+.
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5.
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   

6.
1.  If the adsorption centers are located at such great distances that the local magnetic field induced by the nuclei of the adsorbate molecule has an appreciable value only at the nucleus of the center nearest to it, the second moment of the NME resonance line from the nuclei of the adsorption centers should increase linearly with increasing adsorption. The slope of this straight line contains information on the position of an individual molecule relative to an adsorption center.
2.  The second moment of the7Li NMR line for zeolite LiA at 120 K increases linearly as the zeolite is filled with water up to an amount of water approximately equal to the number of Li+ in the zeolite. The slope of this straight line corresponds to the average distance between a proton and a7Li nucleus, which equals 0.279 ± 0.1 nm.
3.  As zeolite LiA is filled with water, the7Li NMR resonance line approximates the shape of a Lorentzian line.
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7.
1.  The activity of cobalt-group II metal oxide catalysts in the hydropolymerization reactions of C2-C4 olefins, initiated by CO at 190°, depends on the nature of the oxide and decreases when going from BeO to BaO.
2.  In their reactivity the olefins fall into the order: C2 > C3H6 >-C4H8 > i-C4H8.
3.  The degree of reduction of the cobalt found in the catalyst depends on the nature of the employed oxide and (toes not determine its activity.
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8.
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.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 166–170, January, 1988.  相似文献   

9.
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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10.
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.
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11.
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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12.
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.
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%).
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13.
1.  The condensation of 1,2-hydroxylamino oximes with biacetyl leads to 1-hydroxy-2-acetyl-2,4,5,5-tetrasubstituted 3-imidazoline 3-oxides.
2.  When 1-hydroxy-2-acetyl-2,5,5-trimethyl-4-phenyl-3-imidazoline 3-oxide is oxidized the CH3CO group is cleaved to give the 5H-imidazole 1,3-dioxide.
3.  Stable nitroxyl radicals were obtained when the 1-hydroxy-2-oximiaoethyl-2,4,5,5-tetrasubstituted 3-imidazoline 3-oxides are oxidized.
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14.
1.  Nitroxyl biradicals of the triazine, N,N-bis(triazinyl)ethylenediamine, N,N-bis(triazinyl)piperazine, and s-nitropyrimidine series have been prepared.
2.  The ESR spectra of liquid and frozen solutions of these biradicals have been obtained and N. - O group separations calculated.
3.  Toluene solutions of (II), (V), (VI), and (X) biradicals contain at least four different conformations, each with its own value of the exchange integral.
4.  In one of the biradical (V) conformations, spin interaction exchange is through the chain of atoms linking the N.-O fragments.
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15.
1.  The kinetics of reactions of alkali metal salts of 9-carbomethoxy- and 9-cyanofluorene with para-nitrofluorobenzene and of Me3SnM with pentafluoropyridine have been studied.
2.  In the case of carbanions the free anions are more reactive, while in the case of Me3SnM the corresponding tight (contact) ion pairs are more reactive.
3.  The effect of the leaving group (on reactivity) was investigated using the reactions of pentafluorochlorobenzene with the K salts of 9-carbomethoxyfluorene and cyclopentadienylirondicarbonyl anions as examples.
4.  The reaction mechanism has been shown to depend on the nature of the nucleophile.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2826–2832, December, 1988.  相似文献   

16.
1.  It has been shown that 2-bromo-l,3,2-dioxaarsenanes exist in chair conformation with axially oriented As-Br bonds.
2.  Polarity and polarizability parameters have been found for the As-O and As-Br bonds in 2-bromo-l,3,2-dioxaarsenanes.
3.  The so-called -effect is stronger in the O2AsBr group than in the O2AsCl group.
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17.
1.  Dimethyl, diphenyl, and tetramethylene sulfoxide hydrochlorides react with methylheptenyl, citronellyl, and geranyl acetates to give predominantly the allylic chlorination products.
2.  These findings are preferably to be regarded as involving AdE reactions between the weakly electrophlic hydroxy and (or) chlorosulfonium cation and the trisubstituted C=C bond in these olefins at the key stage.
3.  The addition of lithium perchlorate has been found to accelerate this reaction.
4.  Sulfoxide hydrobromides are highly selective brominating agents for the terminal grouping in isopropenoid oligoolefins.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1797–1803, August, 1988.  相似文献   

18.
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.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 782–786, April, 1989.  相似文献   

19.
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.
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20.
1.  Catalytic dimerization of spiro[2.4]hepta-4,6-diene (I) into dispirocyclopropan-5,1'-endotricyclo [5.2.1.02,6]deca-3,8-dien-10,1-cyclopropane (II) was carried out.
2.  It was established that [Rh(CO)2Cl]2 catalyzes transformation of dispirocyclopropan-6,1'-pentacyclo [5.3.0.02,5.03,9.04,8]-decan-10,1-cyclopropane (XI) into the dimer spiro[2.4]hepta-4,6-diene (II).
3.  Upon reduction of dispirocyclopropan-6,l'-pentacyclo[5.3.0.02,5.03,9.04.8]decan-<>-cyclopropane in the presence of PtO2 1,1,3,3-tetramethyl-1,3-bishomocubane is formed.
4.  The possibility of synthesizing adamantane, diamantane, and their derivatives by skeletal isomerization of hydrocarbons obtained from spiro[2.4]hepta-4,6-diene has been shown.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2152–2155, September, 1988.  相似文献   

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