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1.
| 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. |
2.
I. A. Grigor'ev I. A. Kirilyuk V. F. Starichenko L. B. Volodarskii 《Russian Chemical Bulletin》1989,38(7):1488-1494
| 1. | Oxidation of 5-R1-2R2-4H-imidazole 1,3-dioxides in methanol with lead dioxide leads to the formation of stable nitroxyl and nitronylnitroxyl radicals with methoxy groups at the -carbon atom of the radical center. The ratio between these radicals is determined by the electronic character of the substituents at the 2- and 5-positions of the heterocyclic ring. |
| 2. | Oxidation of 4H-imidazole 1-oxides and 4H-imidazole 3-oxides in methanol with lead dioxide leads to the formation of iminonitroxyl radicals. |
| 3. | Oxidation of 2-unsubstituted 4H-imidazole 1,3-dioxides and 4H-imidazole 3-oxides in alcohols by lead or manganese dioxides leads to 2,2-dialkoxy-substituted stable nitroxyl radicals, which are derivatives of 3-imidazoline 3-oxide and 3-imidazoline. |
3.
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. |
4.
F. P. Sidel'kovskaya V. A. Ponomarenko M. G. Zelenskaya A. V. Ignatenko O. D. Trifonova É. A. Abdula-Zade A. G. Kechina L. A. Sinitsyna 《Russian Chemical Bulletin》1976,25(3):587-593
| 1. | Some new -oxides were synthesized, which contain a lactam ring in the substituent and have the general structure: where R = H, CH3; OC OC2H5, and Z = CH2, CH2OCH2, (CH2)2OCH2. |
| 2. | It was shown on the example of the synthesized glycidyl ethers that they are capable of forming polymeric products under the influence of nucleophilic agents, and also of adding water, ammonia, and diethylamine under mild conditions. |
5.
| 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%. |
6.
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. |
7.
| 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. |
8.
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. |
9.
| 1. | As the number of fused rings in the ligand of the cuprous organoacetylenides with the general formula ArCCCu, where Ar may be phenyl, -naphthyl, -naphthyl, or 9-anthracenyl, is increased, there is a tendency toward a bathochromic shift in the absorption, photoconductivity, and photoelectromotive-force spectra. Para substituents in the phenyl ring cause increasing bathochromic shifts in the absorption maxima along the series CH3 < h=">< cl=">< i="><>3 <>2. |
| 2. | The photoeleetromotive-force spectra are similar to the absorption spectra, and the principal photoconductivity maximum is located on the edge of the absorption band. |
| 3. | The photoconductivities determined from the absorption spectra and the energies of the forbidden gaps determined from the photoelectromotive-force spectra correlate well with each other. This indicates that the conductivity of the cuprous organoacetylenides is intrinsic. The p type of the photocurrent carrier has been established. |
| 4. | The nature of the spectra of the cuprous organoacetylenides as a function of the method of construction has been discussed, and the decisive role of the steric factors in the migration of the photocurrent carriers has been shown. |
10.
T. Ya. Medved' M. V. Rudomino V. N. Avilina N. V. Churilina K. F. Paraskevova N. M. Dyatlova M. I. Kabachnik 《Russian Chemical Bulletin》1976,25(11):2280-2284
| 1. | A new group of ethylenediaminodialkylphosphonic acid esters and higher alcohols has been synthesized. |
| 2. | Study has been made of the extraction of Au(III) from hydrochloric acid solution by the esters of these acids. It has been shown that the extract is a 11 metal-to-ligand complex. The distribution coefficient of the Au(III) extraction increases with the dielectric constant of the extracting solvent. It has also been established that the Au(III) can be reextracted out of the organic phase by NH3 or HNO3. |
| 3. | Study has been made of the extraction of Nd(III), Ce(III) and Ce(IV) ions by the octyl ester of ethylene-diaminodiisopropylphosphonic acid. Extraction of these ions can be carried out almost quantitatively at pH values in the 7.5–8.5 interval. |
11.
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. |
12.
E. I. Matrosov N. P. Nesterova A. I. Zarubin I. A. Komolova T. Ya. Medved' M. I. Kabachnik 《Russian Chemical Bulletin》1988,37(5):935-939
| 1. | Using thermometric titration and IR spectroscopy, we investigated the reaction of carbamoylmethylphosphoryl compounds (CMP) and of some monophosphoryl compounds with HNO3 in dichloroethane and in CCl4. |
| 2. | The interaction between CMP and HNO3 takes place in two stages with sharply different H values which correspond to the formation of molecular complexes at the P=O and C=O groups. |
13.
D. N. Kravtsov V. D. Vil'chevskaya P. V. Petrovskii Yu. Yu. Gorelikova 《Russian Chemical Bulletin》1988,37(5):991-994
| 1. | Ferrocene reacts with bromoadmantane in the presence of A1Cl3 to give mono- and 1,1-diadamantylferrocene. |
| 2. | Acylation of adamantylferrocene with raonoethyl o-phthaloyl chloride takes place in the 3-position of the substituted ferrocene ring, and to some extent in the free cyclopentadienyl ring. |
14.
| 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. |
15.
| 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. |
16.
| 1. | It was shown on the example of the reaction of 1-hydroxy-5-methyltetrazole with methyl vinyl ketone that N-hydroxytetrazoles attach to substances with activated multiple bonds. The addition products are solely the products of N(3 and 4)--oxoalkylation. |
| 2. | Upon heating, 3- and 4--oxoalkylated 1-oxides of tetrazoles are in a tautomeric equilibrium. |
17.
| 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. |
18.
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. |
19.
Time- and temperature-dependent SAXS-experiments were used to determine the effect of octene and butene co-units on the lamellar structure and the melting properties of polyethylene. As expected, melting points decrease with increasing co-unit content, but crystal thicknesses are not affected and depend on the crystallization temperature only. Results can be cast into some simple equations which describe the dependence:
相似文献
| 1. | Of the melting point Tf on the crystal thickness dc and the co-unit content xB |
| 2. | Of the equilibrium melting point on xB |
| 3. | Of dc on the crystallization temperature Tc |
| 4. | Of the long spacing L on Tc, xB and the molar mass |
| 5. | Of Tf on Tc. |
20.
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. |