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1.
The reaction of ,-bis(1,3-thiazan-2-thion-4-on-3-yl)alkanes with hydrazine gives the corresponding ,-di(4-thiosemicarbazido)alkanes, which are readily acylated. Subsequent dehydration of the acylation products gives the corresponding 5,5-dialkyl-,-bis(2,3-dihydro-1,2,4-triazole-3-thion-4-yl)alkanes, which are converted to 5,5-dialkyl- , -bis (1,2,4-triazol4-yl)alkanes by known methods. The UV and ER spectral data are presented.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1060–1062, August, 1977.  相似文献   

2.
Benzene is shown to be adsorbed on the surface of a V2O5-MoO3 catalyst in two forms. The activation energies of benzene desorption for its first and second forms are 50 and 134 kJ/mol, respectively, in the latter case the adsorption proceeding with dissociation.
, - . 50 / –134 /, .
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3.
The thermal properties of some sulphosuccinates and their intermediates were studied by using combined dynamic thermal analysis and mass spectrometry. The temperature ranges were similar in the two methods, and a scheme of thermal decomposition of the compounds investigated was suggested. In the first temperature range of thermal decomposition of the sulphosuccinate a-rupture of the molecular ion occurs. In the second temperature range, the fragmentation proceeds in two directions: either-rupture of the ethoxylated nonylphenol, or-rupture of the acid residue of the sulphosuccinates.
Zusammenfassung Mittels einer Kombination von dynamischer Thermoanalyse und Massenspektroskopie wurden die thermischen Eigenschaften einiger Sulfosukzinate und deren Zwischenprodukte untersucht. Im ersten Temperaturbereich der thermischen Zersetzung des Sulfosukzinates findet eine-Spaltung des Molekülions statt. Im zweiten Temperaturbereich tritt auch ein alternativer Fragmentierungsweg auf: eine-Spaltung des Säurerestes des Sulfosukzinates.

- . . - -. : - - .
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4.
Summary We have suggested an improved method for preparing , -dinitroalkanes which consists in the action of silver nitrite on , -dibromoalkanes in petrofeum ether medium with heating.  相似文献   

5.
Summary An ,-appended eighteen carbon chains hypercin derivative (2) was synthesized starting from emodin. The overall yield of the seven step synthesis was 12%. The1H and13C NMR, absorption, and emission spectroscopic properties were measured;2 can be dissolved even in apolar solvents and polyethylene.
Synthese und Eigenschaften eines mit C18-Ketten ,-substituierten Hypericinderivats
Zusammenfassung Ein in den Positionen , mit zwei C18-Ketten substituiertes Derivat des Hypericins (2) wurde ausgehend von Emodin synthetisiert. Die Gesamtausbeute der siebenstufigen Synthese betrug 12%. Die1H- und13C-NMR, absorptions- und emissionsspektroskopischen Eigenschaften wurden gemessen;2 kann sogar in apolaren Lösungsmitteln und Polyethylen gelöst werden.
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6.
The effect of representing dielectric properties in terms of the complex polarizability c = – i is examined. Loss curves ( and tan ) are shifted towards higher frequencies, revealing the existence of new relaxations and allowing the clarifications of ones already known. We have calculated the shift ratios (at maximum or tan )/ (at maximum or tan ) from the more conventional empirical equations representing the dielectric behavior. Some examples are given.  相似文献   

7.
Conclusions The,-dichloro--bromoalkanes and,-dichloro--bromoalkenes react with the benzyl- and allylmagnesium halides in tetrahydrofuran solution to give,-dichloroalkyl(alkenyl)benzenes,,-dichloroalkadienes in high yields. For all practical purposes the reactions do not go in ether.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 886–890, April, 1972.  相似文献   

8.
Reducibility of a series of RECoO3 (RE=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy) perovskite-type oxides were measured by temperature programmed reduction (TPR) technique. Catalytic activity for CO oxidation of them were investigated. The relation among Tmax in TPR, catalytic activity and surface oxygen binding energy is discussed.
RECoO3 (RE=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy) . CO. Tmax , .


Project Supported by the Science Fund of the Chinese Academy of Sciences  相似文献   

9.
The geometries and energies of 1 and 2 radicals, formed in the thermal reaction of dimethyl- and diethyldiazenes, were investigated by means of UHF-MINDO/3. The stability of radicals was found greater than that of allyl radical. The calculated SOMO energies show a lower reactivity in H-abstraction reactions than that of alkyl and allyl radicals.
UHF-MINDO/3 1 2, - . 1 , . SOMO , .
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10.
Galvanic cells of the type (C+Cl2)(NaCl(s))(MCl2(s))(C+Cl2) give e. m. f. 's above 280°, which are due to the formation of ternary chlorides NanMCln+2. By the change in slope of continuously measured e.m.f.vs. T curves, the temperatures of solid-state reactions in systems NaCl-MCl2 can be found. This method was applied for the systems of NaCl with NiCl2, CoCl2 and CdCl2, and for KCl-NiCl2. With the exception of the system NaCl-NiCl2, all phase diagrams must be corrected.
Zusammenfassung Mit galvanischen Zellen des Typs (C+Cl2)/NaCl(s)/MCl2(s)/(C+Cl2) lassen sich oberhalb 280° EMK's messen, die auf der Bildung ternärer Chloride NanMCln+2 beruhen. Durch die Änderung der Steigung kontinuierlich gemessener EMK- gegen T-Kurven lassen sich in Systemen NaCl/MCl2 die Temperaturen von Festkörperreaktionen nachweisen. Diese Methode wurde auf die Systeme des NaCl mit NiCl2, CoCl2 und CdCl2 sowie auf das System KCl-NiCl2 angewendet. Alle Phasendiagramme, mit Ausnahme des Systems NaCl-NiCl2, mußten auf Grund dieser Messungen revidiert werden.

(C+Cl2)/NaCl./MCl2./(C +Cl2) 280 °C . . , NanMCln+2. . . , NaCl-MCl2. NaCl NiCl2, CoCl2, CdCl2 KCl-NiCl2. NaCl-NiCl2,ce .


This work was supported by the Deutsche Forschungsgemeinschaft and the Fonds der Chemischen Industrie.  相似文献   

11.
1,3-Dihydrobenzo[c]selenophene was synthesized from , -dibromo-o-xylene and sodium selenide.Translated from Khimiya Geterotsiklicheskikh Soedin-enii, No. 1, p. 24, January, 1972.  相似文献   

12.
Zusammenfassung Der induktive Effekt einer an ein aromatisches oder konjugiertes System gebundenen GruppeG wird durch die Änderung desCoulombintegrals desjenigen C-Atoms, an das die GruppeG direkt gebunden ist, berücksichtigt, indem für dieses s = + angesetzt wird. Der den induktiven Effekt quantitativ beschreibende Parameter kann aus UV-Spektren abgeleitet werden. Die Prozedur dieser halbempirischen Bestimmung von wird allgemein beschrieben und begründet.Mit 1 AbbildungDie wesentlichen Teile dieser Arbeit wurden während meiner Zugehörigkeit zur Quantum Chemistry Group des Mathematical Institute, University of Oxford, im Studienjahr 1957/58 ausgeführt. Vgl. Progress Report, Session 1957–1958, S. 26.  相似文献   

13.
A series of 1,1-dihydroperfluorooxaalkan-1-ols and ,,,-tetrahydroperfluorooxaalkanediols has been synthesized. Some tercphthalates were synthesized by the reaction of these alcohols and diols with terephthaloyl chloride.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1573–1576, June, 1996.  相似文献   

14.
Characteristic peculiarities of the supercarbonization peak, i. e. the effect of carbon accumulation on the catalyst surface and its subsequent removal under heating in the CH4+CO2 mixture have been studied. Hysteresis of thermogravimetric curves in the heating/cooling cycle has been established.
— . -.
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15.
Composition and catalytic properties in ethylene polymerization of supported systems prepared via the interaction of Ti(CH2C6H5)3X (X=F, Cl, Br) and Zr(CH2C6H5)2Cl2 complexes with silica and alumina have been studied. Halide addition to benzyl complexes decreases the polymer molecular mass.
, Ti(CH2C6H5)3X (X=F, Cl, Br) Zr(CH2C6H5)2Cl2 SiO2 Al2O3. , .
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16.
A general method for the synthesis of optically active 9-purinyl--amino acids by condensation of 5-amino-4,6-dichloropyrimidine with ,-diamino carboxylic acids and subsequent cyclization of the N-(5-amino-4-chloro-6-pyrimidinyl)-amino acids with triethyl orthoformate was developed. A number of 6-substituted -amino--(9-purinyl) carboxylic acids were obtained by nucleophilic substitution of the chlorine atom in the -amino--(6-chloro-9-purinyl) carboxylic acids.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1690–1695, December, 1982.  相似文献   

17.
-Al2O3 is modified by lithium additions and by calcination. Aniline alkylation activity over modified alumina is correlated with the Al–OH group population responsible for the acidity.
-Al2O3 . Al–OH, .


IICT Communication No.: 2824  相似文献   

18.
It is suggested that besides its traditional application to describe random nucleation, the first-order equation F1 can be used for the diffusion kinetics of gas-solid small particles reactions.
, F1 - - .
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19.
New measurements and literature data on polysiloxanes covering heat capacities, transition parameters, enthalpies, entropies and Gibbs energies are presented and critically reviewed. TheATHAS computation method is used to bring heat capacities into agreement with an approximate frequency spectrum. The various crystal and mesophases are discussed. TheATHAS (1990) recommended data are as follows: For poly(dimethyl siloxane) the glass transition is at 146 K with an increase in heat capacity of 29.24 J/(K mol). The completely crystalline sample melts at about 219 K with a heat of fusion of 2.75 kJ/mol. For poly(diethyl siloxane) the glass transition is at 135 K with an increase in heat capacity of 34.48 J/(K mol). The completely crystalline sample changes to a condis crystal at 206.7 K with a heat of disordering of 2.72 kJ/mol. The transition to a poorly characterized viscous crystal with thermodynamic properties close to the melt occurs at 282.7 K with an enthalpy of transition of 1.84 kJ/mol. Final fusion occurs at 308.5 K and a small endotherm of about 231 J/mol. Tables of heat capacities, enthalpies, entropies and Gibbs energies are given from 0 K to 550 K.
Zusammenfassung Neue Messungen und Literaturangaben von Polysiloxanen über Wärmekapazität, Umwandlungsparameter, Enthalpien, Entropien und Gibbssche Energien werden vorgestellt und kritisch betrachtet. Das Rechenverfahren ATHAS wurde benutzt, um die Wärmekapazitäten mit einem annähernden Frequenzspektrum in Einklang zu bringen. Es wurden die verschiedenen Kristall- und Mesophasen diskutiert. Die von ATHAS (1990) empfohlenen Werte sind wie folgt: Für Poly(dimethylsiloxan) beträgt der Glasumwandlungspunkt 146 K bei Zunahme der Wärmekapazität um 29.24 J/(K.mol). Die vollständing kristalline Probe schmilzt bei etwa 219 K mit einer Schmelzwärme von 2.75 kJ/mol. Für Poly(diethylsiloxan) beträgt der Glasumwandlungspunkt 135 K bei Zunahme der Wärmekapazität um 34.48 J/(K.mol). Die vollständig kristalline Probe wandelt sich bei 206.7 K um, die Fehlordnungswärme beträgt 2.72 kJ/mol. Die Umwandlung in einen wenig verstandenen viskosen Kristall, dessen thermodynamische Eigenschaften denen der Schmelze gleichen, erfolgt bei 282.7 K mit einer Umwandlungsenthalpie von 1.84 kJ/mol. Letztendlich verläuft das Schmelzen bei 308.5 K mit einem kleinen endothermen Effekt von etwa 231 J/mol. Wärmekapazitäten, Enthalpien, Entropien und Gibbssche Energien sind für den Bereich 0 K–550 K tabellarisch angegeben.

, , , , . ATHAS , - . . ATHAS (1990) : 146 29,24 / ·. 219 2,75 /. 135 34,48 /·. 206,7 2,72 /. « » 282,7 1,84 /. 308,5 231 /. , , 0–550 .


This work was supported by the National Science Foundation, Polymers Program, Grant #DMR 83-17097 and early work of J.P.W. was supported by the Am. Chem. Soc. Petroleum Research Found, Grant 12431-AC7. In addition at Oak Ridge National Laboratory the work was sponsored by the Division of Materials Sciences, Office of Basic Energy Sciences, U.S. Department of Energy under contract DE-AC05-84OR21400 with Martin Marietta Energy Systems Inc.  相似文献   

20.
The condensation of aminals of -dimethylaminoacrolein and 5-dimethylaminopenta-2,4-dienal with cyclic and acyclic 1,2-, 1,3-, 1,4-, 1,5-, and 1,6-diketones was studied. A series of previously unknown bis(,-dimethylaminopolyenyl)diketones was synthesized; their structures were established by means of1H and13C NMR spectroscopies. The electron absorption spectra were employed to study the mutual influence of -aminopolyene chromophores separated by two C=O groups.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1235–1241, July, 1993.  相似文献   

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