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1.
A. M. Voloshchuk M. M. Dubinin T. A. Moskovskaya A. O. Larionova L. A. Shilkova 《Russian Chemical Bulletin》1988,37(10):1979-1983
| 1. | The adsorption isotherms of N2 at 77 K on the surface of carbonaceous adsorbents in the region of low relative pressures are satisfactorily described by the Dubinin-Radushkevich (DR) equation. However, the a0 parameter of the DR equation is not related to the monolayer capacity, and for samples with the most homogeneous surface the quantity a0 substantially exceeds the BET monolayer capacity. |
| 2. | The adsorption isotherms calculated per unit surface area of adsorbent can be grouped in terms of the E0 value of the DR equation; this can be regarded as a measure of the degree of energetic heterogeneity of the samples. |
| 3. | For samples with E0 < 15.5="" kj/mole,="" the="" specific="" surface="" areas="" calculated="" by="" the="" bet="" method="" and="" by="" the=""> and methods are similar. |
| 4. | The samples of carbonaceous adsorbents with E0 > 15.5 kJ/mole are characterized by surface heterogeneity associated with the presence of micropores. |
2.
Yu. V. Maksimov P. Ya. Kolotyrkin Yu. V. Baldokhin A. V. Krylova 《Russian Chemical Bulletin》1989,38(7):1344-1349
| 1. | The protective layer of microcrystalline iron consists of crystallites of hematite magnetically ordered at 20C and 0.1 m in size, and the phase composition of the surface and bulk of the sample is qualitatively the same in all conditions of oxidation. |
| 2. | The passivating film of the promoted catalyst of synthesis of ammonia is formed from small clusters of iron oxide with an effective size of 0.005–0.01 m; the composition of the surface and bulk of the stabilized catalyst is qualitatively different. |
| 3. | The role of the defects in the promoted catalyst in the mechanism of formation of oxide clusters was discussed. |
3.
V. A. Ermolaeva G. A. Marchenko V. I. Markovskii V. I. Slovetskii S. S. Novikov 《Russian Chemical Bulletin》1976,25(12):2495-2498
| 1. | Study has been made of the IR spectra of N--polynitroalkylhydrazine derivatives, band assignments being made for stretching vibrations in the NH, C=O, and NO2 groups. |
| 2. | Integral intensities for NO2 antisymmetrical stretching absorption bands are additive. Splitting of these bands is characteristic of nitro compounds containing a hydrazine radical in the -position with respect to the nitro group. |
| 3. | It has been shown that intermolecular hydrogen bonding exists in the N--polynitro-alkylhydrazines, in the crystalline state and in concentrated solution. |
4.
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. |
5.
Kozlovskii A. G. Arinbasarov M. U. Yakovlev G. I. Zyakun A. M. Adanin V. M. 《Russian Chemical Bulletin》1976,25(5):1115-1119
| 1. | An earlier unknown metabolite ofPseudomonas aeruginosa, strain A197, 2-(n-1-heptenyl)-4-quinolone, was isolated. |
| 2. | The main components of the total mixture of alkaloids produced byPseudomonas aeruginosa strain A197 are 2-n-nonyl-4-quinolone (pseudane-IX), 2-n-heptyl-4-quinolone (pseudane-VII), 2-(n-1-nonenyl)-4-quinolone (1pseudene-IX), and 2-(n-1-heptenyl)-4-quinolone (1-pseudene-VII). |
| 3. | The synthesis of 2-(n-1 -heptenyl)- 4 -quinolones was carried out. |
6.
N. G. Zharova I. O. Shapiro I. A. Misurkin E. D. German 《Russian Chemical Bulletin》1988,37(2):283-288
| 1. | According to the data from quantum-chemical calculations, the stability of the nitromethane and toluene molecules in the orthogonal and parallel conformations is practically the same. The ethylbenzene molecule is more stable in the orthogonal conformations. The 2-nitropropane and cumene molecules are more stable in the parallel conformation. The planar structure is the most favorable for the anions of these compounds. |
| 2. | The geometric parameters and the charges and the atoms were determined for the most stable structures of the nitromethane, 2-nitropropane, toluene, ethylbenzene, and cumene molecules and anions. |
| 3. | The methyl groups at the deprotonated C atom increase the stability of the 2-nitropropane, ethylbenzene, and cumene anions. |
7.
| 1. | In the nucleophilic addition of alcohols to alkylacetylenes (methyl- and tert-butyl-), the regiospecificity of the attack of alkoxide converts to regiose lectivity with the increasing steric requirements of the substituent in the alkyne and of the attacking nucleophile. |
| 2. | The reaction leading to the adduct takes place with strict steric specificity by a nucleophilic mechanism of 1, 2-anti-addition with the formation of cis isomers; this behavior is independent of steric hindrances. |
8.
L. F. Godunova E. S. Levitina E. I. Karpeiskaya E. I. Klabunovskii Yu. L. Yagupol'skii M. T. Kolycheva 《Russian Chemical Bulletin》1989,38(2):351-354
| 1. | Catalytic reductive aminolysis of the azalactones of N-acyl-p-difluoromethoxy--aminocinnamic acid in dimethoxyethane, isopropanol, and tert-butanol proceeds stereoselectively, leading to the -phenylethylamides of N-acyl-p-difluoromethoxyphenylalanine with a 3–55% excess of the S,S-diastereomer. |
| 2. | Replacement of dimethoxyethane by isopropanol or tert-butanol leads to an increase in the stereoselectivity of the process. |
| 3. | Hydrogenation of the S-(+)--phenylethylamide of N-acyl-p-difluoromethoxy--aminocinnamic acid proceeds stereoselectively, and leads to production of the -phenylethylamide of N-acyl-p-difluoromethoxyphenylalanine with a 9–18% excess of the R,S-diastereomer. |
9.
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. |
10.
D. D. Gogoladze E. S. Levitina L. F. Godunova E. I. Karpeiskaya E. I. Klabunovskii G. O. Chivadze 《Russian Chemical Bulletin》1988,37(6):1207-1210
| 1. | Hydrogenation of -nitrpcaprolactam by treatment with a Pd catalyst in the presence of S--phenylethylamine in aprotic solvents proceeds via azoxycaprolactam as an intermediate. |
| 2. | The asymmetric effect in the enantioselecive hydrogenation of nitrocaprolactam on a chiral Pd catalyst occurs at the stage where azoxycaprolactam is reduced. |
11.
A. N. Nesmeyanov N. E. Kolobova I. B. Zlotina B. V. Lokshin I. F. Leshcheva G. K. Znobina K. N. Anisimov 《Russian Chemical Bulletin》1976,25(5):1093-1097
| 1. | The reaction of tetrakis(trifluoromethy1)allene with -C5H5Fe(CO) 2 – and Re(CO) 5 – gives -complexes. |
| 2. | On irradiation and heating, the -complex of iron is converted into the -allylidene complex. |
12.
A. M. Kritsyn L. I. Kolobushkina S. N. Mikhailov V. L. Florent'ev 《Russian Chemical Bulletin》1976,25(2):384-387
| 1. | 9-(3-Aminopropyl)adenine, racemic 9-(2-hydroxy-3-amitiopropyl)adenie and its (R)-enantiomer, and 9-(2-hydroxy-3-methylaminopropyl)adenine were synthesized. |
| 2. | A study was made of the NMR spectra of the reaction products of the -tosyloxyalkyl derivatives of uracil and thymine with ammonia and methylamine. Theories were expressed regarding the structure of the formed compounds. |
13.
L. S. Zakharov E. I. Goryunov S. T. Ioffe L. L. Morozov T. M. Shcherbina M. I. Kabachnik 《Russian Chemical Bulletin》1976,25(8):1727-1731
| 1. | The catalytic phosphorylation of -polyfluoralkylbenzyl alcohols with an excess of phosphoryl chloride in the presence of a catalyst in the form of an alkali- or alkaline-earth metal chloride has been studied. |
| 2. | Depending on the substituent in the benzene ring, the reaction leads to the formation of -polyfluoralkylbenzyl dichlorophosphates or (in the presence of an electron-donating substituent) to the formation of the corresponding simple benzyl ethers. |
14.
L. Kh. Freidlin L. I. Gvinter V. A. Zamureenko L. N. Suvorova 《Russian Chemical Bulletin》1976,25(4):795-797
| 1. | Intermediate enol formation has been registered by deuterium exchange in the hydrogenation products of, -unsaturated ketones on Co/C and Rh/C, indicating 1,4 addition of hydrogen to the enone system. |
| 2. | The presence of 1,4 hydrogen addition to,-unsaturated ketones is determined by the nature of the catalyst; Pd/C does not catalyze this process route. |
| 3. | Modification of Pd catalysts with cadmium changes their orienting action and selectivity in favor of 1,4 hydrogen addition with intermediate enol formation. |
15.
| 1. | Alkylarylketiminoboranes react with nitriles to form boron -diiminates, whose structure has been determined by UV, IR, PMR, and boron-11 NMR spectroscopy. |
| 2. | Depending on their structure, boron -diiminates are hydrolyzed in an acid medium with the formation of either boron -diketonates, or -diketones. |
| 3. | During the reaction of boron -diiminates with HCl or HBF4, boronium salts are formed with -diimines as ligands. |
16.
| 1. | The N-chloro-N-nitroamides of arylsulfonic acids react with olefins to give a mixture of the N- and O--chloroalkylation products of the nitroamides. |
| 2. | When arylsulfonic acid N-chloro-N-nitroamides react with monosubstituted ethylene derivatives the nitroamide group adds to the least hydrogenated carbon atom of the multiple bond. |
17.
| 1. | An isokinetic relation occurs in the-elimination reaction; linearity of free energies is achieved simultaneously. |
| 2. | The isokinetic temperature, which was significantly above the reaction temperature, was determined by different methods. |
18.
G. V. Kryshtal' G. M. Kursonova V. F. Kucherov L. A. Yanovskaya 《Russian Chemical Bulletin》1976,25(3):652-654
| 1. | ,-Dichloropolyene aldehydes react with acetone cyanohydrin in the presence of triethylamine to give -chloropolyenoic esters. |
| 2. | A new method has been developed for the synthesis of Cl(CH = CH)nCOOR, where n = 2 and 3. |
19.
L. F. Chertanova G. A. Marchenko A. A. Gazikasheva Yu. T. Struchkov V. F. Sopin L. N. Punegova A. S. Mukhametzyanov 《Russian Chemical Bulletin》1989,38(2):250-253
| 1. | The planar alkoxydiazinoxide fragments are shown to have the Z-configuration and be orthogonal to each other by an x-ray structure study of a series of alkoxydiazinoxides. |
| 2. | In the oxydiazinoxide fragments, p- conjugation occurs. |
| 3. | The molecules of the compounds in the crystals studied are joined by hydrogen bonds. |
20.
| 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. |