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1.
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. |
2.
A. I. Kokorin L. S. Bogach A. B. Shapiro É. G. Rozantsev 《Russian Chemical Bulletin》1976,25(9):1874-1878
| 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. |
3.
| 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. |
4.
Zh. A. Krasnaya T. S. Stytsenko V. I. Avdeeva D. Ya. Shagalova 《Russian Chemical Bulletin》1989,38(1):80-86
| 1. | A series of tetracyanopolymethines has been synthesized by condensation of aminals and aminal-acetals of conjugated -dimethylaminoaldehydes with malonodinitrile. |
| 2. | These tetracyanopolymethines can be used as the anionic components in cation-anion cyanine dyes. |
| 3. | The electronic absorption spectra of these newly synthesized dyes were studied in both polar and nonpolar solvents. Specific cation-anion interaction and complex formation has been shown to occur in several of these cation-anion dyes in nonpolar solvents. |
5.
| 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. |
6.
| 1. | The strong bathochromic shift of the absorption bands of aminoazo compounds in acid medium is due to the formation of a cation of quinoid structure. |
| 2. | Aminoazo compounds are weak NH acids in aprotic polar solvents, and they form the corresponding mesomeric anions in the presence of alkalis. |
| 3. | The synthesized aminoazo compounds are very weak NH acids, and electron-donor substituents weaken the acid properties of the amino group, while electron-acceptor substituents intensify them. |
7.
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. |
8.
Zh. L. Dykh L. I. Lafer V. I. Yakerson A. M. Rubinshtein A. M. Taber I. V. Kalechits S. S. Zhukovskii V. É. Vasserberg 《Russian Chemical Bulletin》1976,25(2):282-286
| 1. | At 20–220° on aluminum oxide and NaX, NaY, CeNaY, and HY zeolites, aliene isomerizes to methylacetylene; zeolites whose IR spectra are characterized by the presence of absorption bands of the hydroxyl groups (CeNaY, HY) are more active in this reaction. |
| 2. | The thermal dimerization of aliene at 450° proceeds with the formation of 1,2-dimethylenecyclobutane. |
| 3. | The oligomerization of aliene on -allylnickel bromide, applied on aluminum oxide, at 20–180° gives chiefly 1,3-dimethylenecyclobutane, the formation of which evidently proceeds through a four-membered active complex. |
9.
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. |
10.
| 1. | In phosphoryl compound + HCCl3 + CCl4 systems, hydrogen-bonding complexes form with chloroform with 11 and 1 2 compositions. |
| 2. | The enthalpy of formation of a hydrogen bond between a phosphoryl compound and HCCl3 has been evaluated, and it correlates linearly with the shift in the overtone in the range measured. |
| 3. | A linear correlation of -H with the sum of the Taft constants of the substituents on the phosphorus has been found. |
11.
| 1. | The existence of synergism is demonstrated; the activity of Pd-Tc/carrier catalysts in the dehydrogenation of hydrocarbons considerably exceeds that of monometallic catalysts. The most active catalysts are those with PdTc ratios from 11 to 23. |
| 2. | In terms of reactivity on Pd-Tc catalysts, the hydrocarbons are arranged as follows: cyclohexene > cyclohexane > methylcyclohexane > ethylcyclohexane > n-hexane. |
| 3. | Activity in the dehydrogenation of cyclohexane varies as follows: Pd-Tc/-Al2O3 > Pd-Tc/MgO > Pd-Tc/TiO2 > Pd-Tc/Y2O3 > Pd-Tc/SiO2. |
| 4. | A decrease in CO chemisorptive capacity on bimetallic catalysts compared to monometallic catalysts is established. |
12.
| 1. | The existence of a thermodynamic equilibrium between the trans and gauche conformers in ethyldichlorophosphonate, ethyldichlorothiophosphonate, and ethyldichloroselenophosphonate has been established. |
| 2. | The gauche conformer predominates in compounds I–III at 298°K. In the case of ethyldichlorophosphonate the trans isomer remains in the solid phase, in the thio analog the gauche isomer remains, and in the selenium analog the trans and gauche isomers remain. |
| 3. | The experimentally observed difference in the frequencies of the conformers is close to that calculated under the assumption that their force fields are constant. Nevertheless, the frequencies of the stretching vibrations of the multiple bonds are higher in the trans isomers than in the gauche. |
| 4. | One vibration with predominant participation of the P=X bond ( P=O, P=S, and P=Se) has been isolated in the spectrum of each conformer. The characteristic nature of the vibrations for the bonds just cited decreases along the series indicated. |
13.
| 1. | Substituted thiazoles are formed when N-acyl--aminoketones are heated with thioacetic acid and ZnCl2 in ether dioxane or ethyl acetate. |
| 2. | The reaction of acetamidoacetone with thioacetic acid and ZnCl2 at 20° leads to 2,5-dimethyl-5-acetylmercapto-2-thiazoline. |
| 3. | -Formamidoketones are formed when-aminoketone hydrochlorides are heated with orthoformic ester. |
14.
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. |
15.
V. A. Nasluzov A. V. Kondratenko K. M. Neiman L. N. Mazalov 《Journal of Structural Chemistry》1988,29(3):391-400
The present study of cyano complexes leads to the following conclusions.
Institute of Inorganic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 29, No. 3, pp. 53–63, May–June, 1988. 相似文献
| 1. | The x-ray and PE spectra are directly related to the results of quantum-chemical calculations: the IP and the partial charges or populations. Thus the complete set of theoretical x-ray and PE spectra apparently represents one of the most successful ways of obtaining a clear graphical representation of the results of quantum-chemical calculations. |
| 2. | The complete set of x-ray and PE spectra provide a good test for verifying quantum-chemical theory, for selecting a model of the electronic structure, and for refining the procedure for carrying out the calculations, in the present case of the X-SW method the method for selecting the radii of the atomic spheres. |
| 3. | With the optimum selection of the radii of the atomic spheres, the X-SW method describes with satisfactory accuracy those aspects of the electronic structure of coordination compounds that are reflected in the x-ray (except the XE K5 spectra) and PE spectra of the valence orbitals. |
16.
V. M. Denisov E. Yu. Melenevskaya V. N. Zgonnik A. I. Kol'tsov V. M. Sergutin 《Russian Chemical Bulletin》1976,25(9):1868-1870
| 1. | The effect of dilution with inert solvents on the dissociation of BuLi complexes with the electron donors, OMe2, OEt2, NEt3, and SEt2 has been studied through PMR spectra. Data concerning the stability of donor — acceptor complexes has been obtained. |
| 2. | Interaction of BuLi with dimethyl ether leads to the formation of a 11 complex. Fewer than four molecules of the donor add to the tetramer in other cases. |
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. | 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. |
19.
V. I. Avdeev I. I. Zakharov G. M. Zhidomirov N. M. Neshev E. I. Proinov 《Journal of Structural Chemistry》1992,33(2):179-185
| 1. | Upon interaction of OH with Ni(100)m Ni(111), and Ni(110), stable, many-center forms of OH adsorption are produced. One-center and bridge forms of OH adsorption on nickel are kinetically unstable for the lowest surface coverages. |
| 2. | On Ni(100) and Ni(111), a linear form of adsorption of OH is realized; on Ni(110), an angular form is realized, with a polar angle 0 = 20°. |
| 3. | In the course of adsorption, there is a significant transfer of electron density from the metal to the OH, leading to an increase in the work function of the electrons and a decrease in the frequency of the (O–H) vibration. For the angular forms of adsorption, bending vibrations (O–H–Ni) are active. |
| 4. | Upon adsorption of OH, a strong -bond Ni(110)–OH is formed, as manifested in the UV photoelectron spectra by absorption in the 9.2 eV energy region. |
20.
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. |