共查询到20条相似文献，搜索用时 15 毫秒
1.
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. |
2.
| 1. | On Raney Cu and Co catalysts modified with D-(+)-tartaric acid acetoacetic ester is hydrogenated asymmetrically. |
| 2. | The optical yield of (-)-ethyl-3-hydroxybutyrate depends on the nature of the catalyst and the experimental conditions: on Cu catalyst the optical yield reaches 20–24% and is close to the optical yield obtained on modified Ni catalyst: on Co catalyst the optical yield is considerably less (2–8%). With increase in the quantity of catalyst the optical yield on these catalysts passes through a maximum. |
3.
Vol'pin M. E. Savitskii A. V. Novodarova G. N. Kolosova E. M. 《Russian Chemical Bulletin》1976,25(7):1430-1434
| 1. | The chelate cobalt complex Co(II)N, N-bis(salicylidene)ethylenediamine [Co(Salen)] is an effective catalyst for NAD-H oxidation in methanol at room temperature. |
| 2. | The rate of oxidation is closely dependent on the structure of the complex catalyst and the composition of the solvent. |
| 3. | The mechanism of Co(Salen) complex catalytic activity in NAD-H autooxidation is discussed in terms of three proposed reaction schemes. |
4.
M. N. élinson S. K. Fedukovich S. V. Lindeman M. S. Aleksanyan Yu. T. Struchkov G. I. Nikishin 《Russian Chemical Bulletin》1989,38(7):1467-1471
| 1. | On electrolysis in methanol in the presence of the catalyst carrier NaI, tetramethyl propane-1,1,3,3-tetracarboxylate cyclizes with the exclusive formation of tetramethyl cyclopropane-1,1,2,2-tetracarboxylate with the yield up to 98%. |
| 2. | In the presence of NaBr and LiCl, hexamethyl pentane-1,1,3,3,5,5-hexacarboxylate, hexamethyl cyclopentane-1,1,2,2,4,4-hexacarboxylate, and tetramethyl tetrahydrofuran-2,2,4,4-tetracarboxylate are also formed; the last may be obtained with the yield up to 60%. |
5.
V. A. Mamedov I. A. Nuretdinov Yu. Ya. Efremov F. G. Sibgatullina 《Russian Chemical Bulletin》1989,38(4):867-869
| 1. | The reaction of esters of 3-phenyl-3-chloro-2-ketopropionic acid with sodium alcoholates in alcohol (methanol or ethanol) at reflux leads to the formation of an ester of 2,5-diketo-3,4-diphenyl-3-methoxyhexanedioic or 2,5-diketo-3,4-diphenyl-3-ethoxyhexanedioic acid. |
| 2. | The reactions of esters of 3-phenyl-3-chloro-2-ketopropionic acid with the corresponding sodium alcoholates in dilute solution at 0C give the product of the substitution of chlorine by an alkoxy group in quantitative yield. |
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.
V. V. Il'in A. Ch. -V. Kim A. V. Ignatenko V. A. Ponomarenko 《Russian Chemical Bulletin》1989,38(5):1083-1085
| 1. | The reaction of bis(N,N-dimethyl)terephthalamidine with imidates of perfluorohexanecarboxylic acid in diethyl ether gave 1,4-bis(2,4-perfluorohexyltriazinyl)benzene in high yield. |
| 2. | The reaction in methanol leads to the formation of fluorine-containing oligoarylenazomethines. |
8.
| 1. | Bimetallic powdered nickel-cobalt catalysts differing in composition and modified by RR-(+)-tartaric acid were studied in the asymmetric hydrogenation of ethyl acetoacetate. |
| 2. | The optical yield of this reaction is increased to 54% with an increase in the nickel content in the Ni-Co catalyst to 90% and is 60–65% for the nickel catalyst. |
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.
| 1. | Thermodesorption measurements have shown the surface of aluminum-nickel-tungsten sulfide catalysts to be nonuniform with respect to cyclohexane, the nonuniformity being characterized by an exponential distribution, a step adsorption isotherm, and a logarithmic fall off of the desorption activation energy with increasing surface coverage. |
| 2. | The degree of cyclohexane coverage of the catalyst surface is increased by the presence of hydrogen, and the energy of adsorptional bonding is reduced. |
| 3. | Cyclohexane bonds to the catalyst surface more weakly than does benzene, and can be completely displaced from the surface by the latter. |
11.
A. N. Ushakov M. L. Tsirenina V. A. Vaver L. D. Bergel'son 《Russian Chemical Bulletin》1976,25(8):1742-1745
| 1. | The trimethylsilyl derivatives of deacylated acidic nitrogen-free phospholipids have been analyzed quantitatively by GLC. Using the flame-ionization detector, correction coefficients have been calculated with respect to the trimethylsilyl ester of octadecanol. |
| 2. | Simultaneous use of thermionic and flame-ionization detectors facilitates the qualitative interpretation of analytical results. |
12.
N. A. Malysheva A. I. Prokof'ev N. N. Bubnov S. P. Solodovnikov T. I. Prokof'eva V. B. Vol'eva V. V. Ershov M. I. Kabachnik 《Russian Chemical Bulletin》1988,37(5):907-914
| 1. | Conformational transitions characteristic of nonplanar rings were detected in the radical-cation of the 3,6-di-tert-butylpyrocatechol ester of ethylene glycol. |
| 2. | Cyclic radical-cations are formed during the oxidation of 2-acyloxyphenols. |
13.
| 1. | Study has been made of the fragmentation paths in chemical ionization of β-methyl-2,3,4,6-tetra-O-methyl-D-galactopyranoside. |
| 2. | The quasimolecular ions of this compound are capable of successive splitting of one, two, and three methanol molecules, the preferred positions for methoxyl elimination being 1, 3, and 4, respectively. |
14.
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. |
15.
L. A. Rozov Yu. V. Zeifman N. P. Gambaryan Yu. A. Cheburkov I. L. Knunyants 《Russian Chemical Bulletin》1976,25(12):2560-2566
| 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. |
16.
G. Grossman G. Komber G. Kroshvitts P. A. Kirpichnikov N. A. Mukmeneva D. G. Pobedimskii 《Russian Chemical Bulletin》1989,38(1):26-32
| 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. |
17.
| 1. | The selective electrochemical bromoalkoxylation of olefins has been achieved using a membrane-free (diaphragmless) cell to give bromoethers in 60–95% yields, under conditions of cathodic conversion of dibromides formed via competing side reactions back to the olefin precursors. |
| 2. | Bromide ion has been found to catalyze the electrochemical addition of methanol to allylbenzene, resulting in the formation of ethers in 75% yield. |
18.
Ethylene-olefin copolymers differ from other polyethylenes in that:
With the help of a cross-fractionation method we interpreted the differences of the experimental data, according to the molecular mass fractionation and the branching received. 相似文献
| - | there is no long chain branching; |
| - | short chain branching is determined by the comonomer unit; |
| - | the molecular mass distribution is sharp; |
| - | the side chain distribution on different molecules is broad; |
| - | the sequential distribution of branching is very broad along the molecular chains, which becauses a multi-peak lamella distribution, and a multi-peak melting heat. |
19.
| 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. |
20.
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. |