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1.
N. D. Chkanikov V. L. Vershinin M. V. Galakhov A. F. Kolomiets A. V. Fokin 《Russian Chemical Bulletin》1989,38(1):113-119
| 1. | Nonsterically hindered primary arylamines react with hexafluoroacetone benzenesulfonyl- and trifluoroacetylimines to give stable gem-diamino compounds. |
| 2. | The presence of substituents at the nitrogen of the arylamine destabilizes these gem-diamino compounds, with the formation of C2- and C4-alkylation products. With hexafluoroacetone trifluoroacetylimine, C2-alkylation is accompanied by heterocyclization to give 1-substituted 2,4,4-tris(trifluoroacetyl)-1,4-dihydroquinazolines. |
| 3. | N,N-Dialkylanilines are regioselectively alkylated at C4. |
2.
N. F. Yudanov E. G. Boguslavskii I. I. Yakovlev S. P. Gabudar 《Russian Chemical Bulletin》1988,37(2):200-203
| 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. |
3.
| 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+. |
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.
| 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. |
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. |
7.
M. M. Dubinin O. Kadlets L. I. Kataeva B. A. Onusaitis 《Russian Chemical Bulletin》1988,37(5):849-854
| 1. | The adsorption properties with respect to benzene vapors and the pore structure of carbon adsorbents with almost maximum development of the microporosity were studied. |
| 2. | The position of the micropore volume distribution curves whose maxima correspond to a size (halfwidth) of 1.2–1.4 nm and micropore volumes 1.5 cm3/g is a characteristic feature of the adsorbents studied. The difference between ordinary active carbons and the active carbons investigated is only quantitative in the values of the parameters of the Dubinin-Stockley adsorption equation. |
| 3. | The adsorption isotherms are described by the adsorption equation from the theory of volume filling of micropores in a wide range of equilibrium relative pressures and temperatures of 293–353 K with totally satisfactory precision. |
| 4. | The question of the upper limit of the micropores of carbon adsorbents is discussed. |
8.
Z. N. Parnes G. D. Kolemnikova M. I. Kalinkin D. Kh. Shaapuni S. M. Markosyan D. I. Kursanov 《Russian Chemical Bulletin》1976,25(11):2333-2335
| 1. | Platinum hydrides are the active donors of the hydride ion with respect to Ph3 \mathop C? Ph_3 \mathop C\limits^ \oplus . |
| 2. | The phosphine complexes of Ni, Pd, and Pt exhibit catalytic activity in the ionic hydrogenolysis of alcohols, the Pt complexes being the most active. |
9.
| 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. |
10.
I. A. Kalinnikova A. A. Pribylov V. V. Serpinskii T. N. Ivanova S. M. Kalashnikov 《Russian Chemical Bulletin》1988,37(9):1756-1758
| 1. | It has been established experimentally that at 740 K and 90 MPa, approximately three molecules of N2 or O2 are adsorbed in a small cavity of NaA zeolite. |
| 2. | Analysis of the desorption curves indicates that for CsNaA zeolite (degree of exchange of Na+ by Cs+ 70%) it is impossible to distinguish quantitatively between adsorption in the large and the small cavities. |
11.
| 1. | The structure of the isocyanate functional group in organic isocyanates in the crystalline state is analogous to that in the gas phase. |
| 2. | The isocyanate group (H)C1-N=C2=O exists in a trans conformation in all three of the isocyanates studied. |
| 3. | The lamellar packing characteristic of ,-naphthalenediisocyanate molecules may be assigned to a structural subclass of naphthalene ¯1, namely, P(x)P21/b. |
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.
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%). |
13.
Ya. T. Éidus A. L. Lapidus V. I. Mashinskii L. L. Krasnova 《Russian Chemical Bulletin》1976,25(6):1261-1264
| 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. |
14.
| 1. | Polarizability parameters have been determined for the selenocyanate group. |
| 2. | Selenobenzene cyanate, and derivatives of this compound with donor substituants in the p position, have planar conformations; introduction of acceptor substituents breaks down the coplanarity of the C6H4-SeCN fragment. |
15.
G. I. Sarapulova L. I. Volkova B. A. Gostevskii V. A. Lopyrev Yu. L. Frolov 《Russian Chemical Bulletin》1988,37(6):1162-1165
| 1. | The effect of the C6F5 group on the C=0 frequency of C6F5COR compounds depends on the structural features of the R fragment; for ketones, amides, and hydrazides there is steric inhibition of resonance in the C6F5CO group and an increase in the role of the inductive effect from C6F5. |
| 2. | In N-dimethylpentafluorobenzamide the decrease in resonance is compensated by p,-conjugation in the CON group, and the inductive effect of the C6F5 ring appears to be weaker than in pentafluoroacetophenone. |
| 3. | The presence of the second nitrogen atom and the change in relative orientation of the unshared electron pair when affected by substituents at N1 and N2 in pentafluorobenzahydrazide molecules leads to an increase in the torsion angle in C6F5-CO in comparison to N-dimethylpentafluorobenzamide, which increases the -I effect of C6F5 on C=0 in pentafluorobenzhydrazides. |
16.
B. A. Glazun R. N. Kurnosova M. M. Dubinin I. V. Zhilenkov S. S. Levchenko 《Russian Chemical Bulletin》1976,25(1):8-11
| 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. |
17.
Sviridov V. D. Chkanikov N. D. Korbukh I. A. Kolomiets A. F. Fokin A. V. 《Russian Chemical Bulletin》1989,38(7):1519-1522
| 1. | 4-Aminopyrimidines react with hexafluoroacetone to give pyrimidooxazines and pyrimidooxadiazines. |
| 2. | An account is given of the C5 aminoalkylation of 1,3-dimethyluracil by the trifluoroacetylimines of hexafluoroacetone and of the methyl ester of trifluoropyruvic acid. |
18.
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. |
19.
Carbon dioxide fixation by microalgae photosynthesis using actual flue gas discharged from a boiler 总被引：2，自引：0，他引：2
Matsumoto Hiroyo Shioji Norio Hamasaki Akihiro Ikuta Yoshiaki Fukuda Yoshinori Sato Minoru Endo Noriyoshi Tsukamoto Toshiaki 《Applied biochemistry and biotechnology》1995,(1):681-692
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.
相似文献
| 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. |
20.
B. A. Arbuzov I. M. Khamatullina S. G. Vul'fson A. M. Kamalyutdinova A. N. Vereshchagin 《Russian Chemical Bulletin》1976,25(11):2296-2300
| 1. | Polarizability parameters have been obtained for the C6H5-C group in benzylidene bromides, and it has been shown that the bromine atom in these compounds interacts with the aromatic system. |
| 2. | The conformations of the nonsterically hindered benzylidene bromides are close to those in which the ring plane is shielded by the C-Br bond. |