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1.
| 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. |
2.
| 1. | The previously unknown aminooxyalkylcelluloses have been synthesized by alkylation of cellulose with N-substituted -haloalkylhydroxylamines. |
| 2. | The prepared aminooxyalkylcelluloses are weak ion-exchangers, readily react with many classes of organic compounds, and are stable during storage. |
| 3. | Methods have been developed for the preparation of aminooxyalkylcelluloses with different lengths of the pendant H2NO group on the polysaccharide framework. |
| 4. | Sorbents were prepared, based on the aminooxyalkylcelluloses, which contained a covalently bonded coenzyme (pyridoxal-5-phosphate), a substrate (-ketoglutaric acid) and functional groups, able to react with certain functional groups of biopolymers. |
3.
I. V. Anonimova N. A. Chadaeva L. K. Yuldasheva S. G. Vul'fson A. N. Vereshchagin B. A. Arbuzov 《Russian Chemical Bulletin》1976,25(12):2519-2524
| 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. |
4.
| 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. |
5.
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.
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| 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%). |
6.
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. |
7.
| 1. | The (Cp2TiCl)2-LiAlH4 system with Al/Ti from 0.25 to 1.5 catalyzes both the homogeneous hydrogenation and isomerization of allylbenzene. |
| 2. | In an argon atmosphere, allylbenzene is isomerized to trans-propenylbenzene with 90–92% selectivity when Al/Ti=1–1.5. |
| 3. | The possibility was demonstrated for reactivation of this catalytic system by its retreatment with LiAlH4. |
8.
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. |
9.
O. S. Morozova A. A. Kadushin V. A. Khalif E. L. Aptekar' L. Ya. Margolis O. V. Krylov 《Russian Chemical Bulletin》1976,25(4):722-725
| 1. | The surface of a SnO2-Sb2O4 catalyst is uniformly homogeneous with respect to the heats of adsorption of isobutylene. The heats vary from 50 to 20 kcal/mole as the degree of coverage is increased to 18% of a monolayer. |
| 2. | Isobutylene is adsorbed on SnO2-Sb2O4 in two forms: reversible (desorbed in the range 79–100° with Edes=21 kcal/mole) and irreversible. |
| 3. | Irreversibly chemisorbed isobutylene exists on the surface primarily in the form of the-methallyl complex. |
10.
| 1. | It has been shown by PMR spectroscopy that in a solution of RYbI there exists an equilibrium similar to that established by Schenk for Grignard reagents. |
| 2. | The compound formed by the action of an equimolar mixture of PhI and LiI on Yb metal in THF differs in reactivity from PhYbI in its reaction with CF2=CF2. |
| 3. | The reaction of PhSmI with 1,2,2-trifluorostyrene differs from the reactions of PhEuI and PhYbI in that it gives an equimolar mixture of the cis and trans isomers of 5,6-difluoro-4,6-diphenyl-5-hexene-1-ol. |
| 4. | PHCeI does not react with 1,2,2-trifluorostyrene. However, the organocerium complex formed by the oxidatlve addition of Ce to PhI in the presence of an equivalent quantity of LiI reacts with 1,2,2-trifluorostyrene to form an equimolar mixture of the cis and trans isomers of 5.6-difluoro-4,6-diphenyl-5-hexene-1-ol. |
11.
A. S. Vzdykhan'ko V. V. Glushenko M. N. Mirzayanova A. Ya. Khorlin 《Russian Chemical Bulletin》1976,25(3):689-691
| 1. | 2-O-p-Nitrophenyl-N-acetyl--neuraminoside, a suitable substrate for the kinetic study of neuraminidases, was synthesized, and its stability was studied. |
| 2. | The sodium salt of this ketoside is stable during prolonged storage. |
12.
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. |
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.
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. |
15.
| 1. | Potentiometric titration in nitromethane at 25°C has been used to determine dissociation constants for 16 mono-substituted benzoic acids. |
| 2. | Brönsted and Hammett equations have been set up for the compound series under study here. |
| 3. | The data of the literature have been used to evaluate the nitromethane autoprotolysis constant, pKS24. |
| 4. | The relative differentiating action of nitromethane with respect to other solvents has been evaluated from the slopes of the Brönsted and Hammett plots and the values of the autoprotolysis constant. The differentiating action of nitromethane with respect to acids is greater than that of acids with respect to alcohols and acetone, but less than that of DMSO, acetonitrile, and DMF. |
| 5. | Study has been made of the dissociation of the aminobenzoic acids in nitromethane. Solutions of p-aminobenzoic acid are free of zwitterions, while solutions of the m-aminobenzoic acid contain these ions to the extent of 50%. |
16.
Azatyan V. V. Borodulin R. R. Markevich E. A. Rubtsov N. M. Semenov N. N. 《Russian Chemical Bulletin》1976,25(7):1396-1397
| 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. |
17.
| 1. | 1,2-Oxathiolan-5-one-2-oxides are readily cleaved by nucleophiles (H2O, ROH, HNR2) under mild conditions at the O-CO bond only, with the formation of the -(hydroxysulfinyl)-alkanoic acid derivatives. |
| 2. | 2,1-Benzoxathiol-3-one-1-oxide is cleaved by alcohols at both the O-CO and the O-SO bonds to give the unstable monoesters at the carboxyl and sulfinyl groups. |
| 3. | Unlike 2,1-benzoxathiol-3-one-1-oxide, 1,2-oxathiolan-5-one-2-oxides on boiling with excess alcohols give -(hydroxysulfinyl)alkanoic acid bisesters. |
18.
| 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. |
19.
Khurgin Yu. I. Kudryashova V. A. Bakaushina G. F. Khrapko A. M. Zinov'eva N. B. Grigor'ev A. B. Gaiduk V. I. 《Russian Chemical Bulletin》1976,25(4):906-908
| 1. | The absorption of electromagnetic radiation ( 1.05 mm) by solutions of DMSO in water and DMSO and water in dioxane has been measured in the whole interval of relative concentrations. |
| 2. | The additivity of the absorption in systems containing dioxane, and its absence in the system H2O-DMSO, have been demonstrated. |
| 3. | The possibility of using the absorption of radiation in the millimeter range for the study of solvation in solutions has been shown. |
20.
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. |