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1.
The number of parameters in the polynomial is discussed for N components and a polynomial extending up to power n. This number is found to be but may be N less for relative thermodynamic functions. The equation of degree n for an N-component system requires the use of data for each of the i-component systems. Data on the n-component systems suffice if n相似文献   

2.
Conclusions The principal products of the telomerization of propylene with methyl propionate are telomers with the structure , where n=1–4.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2534–2537, November, 1973.  相似文献   

3.
Conclusions The teloHierization of vinyl chloride with methyl propionate was accomplished and it was shown that telomers of type are formed.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2537–2540, November, 1973.  相似文献   

4.
Conclusions Employing the EPR method and 2-methyl-2-nitrosopropane as the spin trap, we recorded the formation of the radicals (n = 1 and 2; X = O, N, or a chain composed of C and O atoms; R = H or alkyl) during the photolysis of acetals and their heteroanalogs in the presence of di-tertbutyl peroxide.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2097–2099, September, 1976.The authors are indebted to A. Sh. Mukhtarov for assistance in running the experiments.  相似文献   

5.
Zusammenfassung Es wird die Frage untersucht, ob bei der thermischen Umlagerung von entsprechend allyl-substituierten o-Benzochinol-acetaten der Allyl- oder der Acetoxylrest rascher wandert. Das 2-Allyl-2-acetoxy-cyclohexadienon liefert bei der genannten Reaktion (es sind schon Temperaturen um 100° ausreichend) überwiegend ein Monoacetat des 4-Allylbrenzcatechins. Damit ist bewiesen, daß der Rest rascher als der Rest in die p-Stellung zur Carbonylgruppe des Chinolacetates wandert. Eine Wanderung des Acetoxylrestes in die o- oder in die p-Stellung zur Carbonylgruppe, welche zur Bildung von 3-Allyl-brenzcatechin bzw. 2-Allylhydrochinon führen müßte, konnte nicht beobachtet werden. Entsprechend liefert das 2,6-Diallyl-2-acetoxy-cyclohexadienon bei der thermischen Umlagerung überwiegend ein Monoacetat des 3,5-Diallyl-brenzcatechins. Nach einem anderen Mechanismus verläuft die Umlagerung des 2-Methyl-6-allyl-2-acetoxy-cyclohexadienons. Es entsteht neben wenig 2-Methyl-6-allyl-hydrochinon in der Hauptmenge ein Monoacetat des 3-Methyl-5-allyl-brenzcatechins. Es wird also die Allylgruppe durch den in die o-Stellung wandernden Acetoxylrest verdrängt. Auf diese Reaktion wird näher eingegangen, weil sie in engem Zusammenhang mit der Frage steht, ob ganz allgemein eine Umlagerung von o-Chinolacetaten vom Typ in die Isomeren möglich ist.Mit 2 AbbildungenHerrn Prof. Dr.F. Feigl zum 70. Geburtstag in alter Freundschaft!F. W. E. Zbiral, F. Wessely undE. Lahrmann, (gilt als 1. Mitt. dieser Reihe), Mh. Chem.91, 331 (1960).  相似文献   

6.
Thermal membrane potentials across the perfluorosulfonic acid-type membrane, Flemion S, were measured for HCl, alkali metal chlorides, and ammonium and methyl ammonium chlorides. The difference between the mean molar transported entropy of the counterions in the membrane and the partial molar entropy of the counterions in the external solution was determined from the experimental data on thermal membrane potential, thermoosmosis and electroosmosis. The sign of the thermal membrane potential in HCl solution varies from positive to negative with the concentration. In HCl and alkali metal chloride solutions, the order of their thermal membrane potentials (–/T) is H+>Li+=Na+>K+ which is roughly the inverse of that of the crystallographic radii of the ions. However, the order of their entropy differences is H+>Na+>K+>Li+ which is just the inverse of that of their thermoosmotic coefficients (D) or the entropy difference of water in thermoosmosis. For the ammonium and methyl ammonium ion forms, the orders of both –/T and increase with an increasing number of methyl groups: (CH3)4N+>(CH3)3NH+>(CH3)2NH 2 + > CH3NH 3 + >NH 4 + , which is also the inverse of that ofD or .  相似文献   

7.
Vibrational spectroscopy and x-ray structure analysis have been used to investigate three new types of sulfonium nitroimides: N-nitrosulfylimides, N-nitrosulfoximides, and N,N-dinitrosulfodiimides. Structural parameters have been determined for the molecules , , and .Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2489–2496, November, 1991.  相似文献   

8.
Summary A new method is described for synthesizing aromatic -amino ketones with the general formula , which is based on the condensation of azlactones with benzene in the presence of aluminum chloride.  相似文献   

9.
Atranes     
A method of synthesizing hitherto unknown 1-aroxysilatranes (R=aryl) is worked out. It is based on transesterification of lower tetraalkoxysilanes with an equimolecular mixture of triethanolamine and the appropriate phenol (naphthol). Using the method, 12 compounds of the indicated type have been prepared and characterized, the yields in the main exceeding 90%.For Part VII see [1].  相似文献   

10.
Several substituted methylaminotriphenylphosphonium salts (APS) of general formula have been synthesized. The CH-acidities of some of the prepared APS have been measured by the indicator method in DMSO, with K+ counterion and 9-phenylfluorene (pK 18.5) as standard, showing a pK range of 14.7–24.8. The acidification effect of and groups has been evaluated. The results obtained suggest that there is an effective charge on the nitrogen atom in the APS studied and an increased multiplicity of the N-P bond.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1598–1604, July, 1991.  相似文献   

11.
A series of mechanisms allowing oscillations and differring in the form of their buffer steps (step 3)
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12.
The aqueous reactions,
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13.
Conclusions The previously proposed structure for the salts of primary nitramines was corro-borated on the basis of the vibrational spectra and quantum-chemical calculations.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 948–950, April, 1972.The authors wish to thank S. Gagarin, who took part in the calculations.  相似文献   

14.
A novel chromium(III) complex of tetraoxalylurea was prepared. In aqueous solutions, [CrIII(H2L)(H2O)]+ (H2L = diprotonated tetraoxalylurea) is oxidized by IO 4 according to the rate law
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15.
Conclusions The direction of the reaction of the silicon hydrides: R2SiH2, RSiH3, and with primary aliphatic amines, in the presence of catalysts based on Group VIII compounds, as a function of the structure of the silicon hydride and the nature of the employed catalyst, was established.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2330–2333, October, 1972.  相似文献   

16.
The kinetics of substitution of aqua ligands fromcis-diaqua-bis(biguanide)cobalt(III) and chromium(III) ions by aspartic acid in EtOH–H2O media have been studied spectrophotometrically in the 30 to 45°C range. We propose the following rate law for the anation
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17.
The electron absorption spectra of alkylvinyl chalcogenides (CH2=CHEAlk, E = S, Se, Te) were analyzed with consideration of the photoelectron spectroscopic data. The following sequence of electronic transitions was found in their UV spectra:
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18.
The title silanethione reacts with phosphorus ylides under conditions of kinetic control to give betaines containing a linear fragment. Under conditions of thermodynamic control, the derivatives of phosphonium 1-silaacenaphthene-1-thiolate are formed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2140–2141, December, 1993.  相似文献   

19.
Conclusions The -allylidene complex is formed in the photochemical reaction of with 1,3-butadiene and 1,3-cyclohexadiene, with subsequent replacement of the carbonyl group by the appropriate ligand.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2130–2131, September, 1977.  相似文献   

20.
Summary Hindered rotation around the bond in the N-acylamidines has been investigated by PMR spectroscopy, and the kinetic parameters of the hindered rotation have been determined.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 758–762, April, 1981.  相似文献   

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