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1.
Kinetic regularities of triphenylphosphite ozonide reaction with triphenylphosphite have been studied at T=–75°C to –40°C. The rate of ozonide consumption is estimated as W=k1[(C6H5O)3P·O3]+k2[(C6H5O)3P·O3][(C6H5O)3P], where k1=(2.03±0.39)×10–5s–1(–50°C), 1gk2=(3.82±0.33)–(6.61±0.32)/gq dm3/mol s and =2.303RT kcal/mol.
–75°C –40°C . : W=k1[(C6H5O)3P·O3]+k2[(C6H5O)3P·O3][(C6H5O)3P], k1=(2,03±0,39)·10–5–1(–50°C); 1g k2=(3,82±0,33)–(6,61±0,32)/ /·, =2,303·RT /
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2.
The holothurianEupentacta pseudoquinquisemita Deichmann collected in Kraternaya Bay, Ushishir Islands has yielded two triterpene pentaosides — the previously known cucumarioside C2, and cucumarioside H, which is a new glycoside. With the aid of13C NMR spectroscopy and solvolytic desulfation its structure has been determined as 6-acetoxy-3-([3-O-methyl--D-xylopyranosyl-(1 3)--D-glucopyranosyl-(1 4)] [-D-xylopyranosyl-(1 4)] [-D-xylopyranosyl-(1 2)]--D-quinovopy-ranosyl-(1 2)-(4-O-sulfato--D-xylopyranosyloxy)holosta-7,22,24(trans)-triene. Cucumarioside H was also identified inEupentacta (=Cucumaria)fraudatrix from Posyet Bay, Sea of Japan.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, USSR Academy of Sciences, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 221–225, March–April, 1988.  相似文献   

3.
    
A universal key component is proposed for the preparation of oligonucleotides with 3- and 5-terminal phosphate groups — 2,3-dibenzoyluridin-5-yl (4-chlorophenylphosphate) (pU(Bz)2), which is a potential source of the phosphate group. The condensation ofpU(Bz)2 with the 5-OH or the 3-OH group of a protected oligonucleotide leads to the formation of oligodeoxyribonucleotides with 5- or 3-terminal uridine, respectively. The oxidation of the 2,3-cis-glycol group of the terminal uridine unit followed by -elimination forms oligodeoxyribonucleotides with terminal phosphate groups.M. V. Lomonosov Moscow State University. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 731–734, September–October, 1987.  相似文献   

4.
A new ecdysteroid — nusilsterone — has been insolated from the whole plantSilene nutans L. It has been shown that it is 1,2,3,14,20R,22R,24,25-octahydroxy-5--cholest-7-en-6-one.Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii. No. 4, pp. 522–525, July–August, 1985.  相似文献   

5.
The values of thermodynamic functions of the following eight organic compounds under non-reacting conditions within the temperature range 298.15 – 550 K are given: N,N dimethylformamide, CHO · N(CH3)2; 4-nitro-1-chlorobenzene, Cl · C6H4 · NO2; sodiump-nitrophenoxide, NO2 · C6H4 · ONa; 1-methyl-2-pyrrolidone, 4,4-dinitrodiphenyl ether, (NO2 · C6H4)2O; 4,4-diaminodiphenyl ether, (NH2 · C6H4)2O; bis-(4-aminophenyl)methane, (NH2 · C6H4)2CH2; bis(4-maleic acidimidphenyl)methane, The relative enthalpy was obtained from calorimetric data by drop calorimetry. The heat capacity and relative entropy are functions derived from the foregoing. The equations of the temperature variation of the relative enthalphy were obtained by computer processing of the calorimetric data by the least squares method. The parameters of solid-liquid transitions were determined from the discontinuity of the temperature variation of the relative enthalpy.
Zusamenfassung Die Werte der thermodynamischen Funktionen folgender 8 organischer Verbindungen werden unter nicht-reagierenden Bedingungen im Temperaturbereich von 298.15 bis 550 K angegeben: Dimethylformamid, CHO · N(CH3)2;p-Nitrochlorbenzol, Cl · C6H4NO2; Natrium-p-Nitrophenoxid, NO2 · C6H4ONa; N-Methylpyrrolidon, 4-4-Dinitrodiphenyläther, (NO2 · C6H4)2O; 4-4-Diaminodiphenyläther, (NH2C6H4)2O; 4-- 4-Diaminodiphenylmethan, (NH2 · C6H4)2CH2; 4-4-bis-Maleinimid-Diphenylmethan, Die relative Enthalpie wird aus kalorimetrischen Daten der Temperaturgefällekalorimetrie erhalten. Die Wärmekapazität und die relative Entropie sind Funktionen der erwähnten Werte. Die Gleichungen der Temperaturänderung der relativen Enthalpie wurden mittels Computerverarbeitung der kalorimetrischen Daten, mit der Methode der kleinsten Quadrate erhalten. Die Parameter der fest-flüssig Übergänge wurden an Hand der Diskontinuität der Temperaturänderung der relativen Enthalpie bestimmt.

Résumé On donne les valeurs des fonctions thermodynamiques des 8 composés organiques suivants, en conditions non réactionnelles, dans l'intervalle de températures 298.15–550 K: diméthylformamide CHO · N(CH3)2,p-nitrochlorobenzène Cl · C6H4 · NO2,p-nitrophé noxysodium NO2 · C6H4 · ONa, N-méthylpyrrolidone dinitrodiphényl-4,4 éther (NO2 · C6H4)2O, diaminodiphényl-4,4 méthane (NH2 ·H 4CH2, 4-4 bis maléinimide diphénylméthane L'enthalpie relative a été obtenue à partir de données calorimétriques fournies par un calorimètre à chute. La chaleur spécifique et l'entropie relative sont des fonction dérivées de la précédente. Les équations donnant la variation de l'enthalpie relative en fonction de la température sont obtenues par traitement des données calorimétriques sur ordinateur par la méthode des moindres carrés. Les paramètres des transitions solide-liquide ont été déterminés à partir de la discontinuité de la variation de l'enthalpie relative avec la température.

, 298,15–550 , : — · N(CH3)2;- — l · 64 · NO2.- -NO2·64·ONa; N-—3·N··2·22; 4,4- — (NO2·64)2; 4,4- — (NH2·64)2; 4,4- — (NH2·64)22; 4,4-- —(64.N. . :. )22. . , . . - .
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6.
The oxidation of amino acids by chloramine-T (CAT) in HCl medium at 30°C indicates simultaneous catalysis by H+ and Cl ions in the HCl concentration range of 0.04–0.12 M. The reaction is first order with respect to concentrations [CAT], [H+] and [arginine], but zero order with respect to [histidine]. The rate depends also on Cl concentration following 0.7th order. At HCl concentrations >0.12 M, the rate equation is:w=k[CAT] [amino acid]0.6 and is independent of the [Cl]. A suitable mechanism has been suggested.
-T (CAT) HCl (30°C) H+, Cl [HCl]=0,04–0,12M. [CAT], [H+] [] []. [Cl]0,7. [HCl]>0,12M =k · [CAT][]0,6 [Cl]. .
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7.
The decomposition of methylcyclohexane on H–NaY and PtH–NaY zeolites has been studied. It has been found that the presence or abscence of H2 affects not only the activity of these catalysts but also their selectivity to dehydrogenation and isomerization products.
H–NaY PtH–NaY. , H2 , .
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8.
Upon the decomposition of silica-supported ammonium paramolybdate, hexagonal MoO3 is formed at 300–350 °C. Irreversible transformation of hexagonal to rhombic MoO3 is observed with increasing calcination temperature. The hexagonal MoO3 structure is probably stabilized by the insertion of ammonium and silicon ions into the lattice of molybdenum trioxide.
, , 300–359 °C . MoO3 . MoO3, , MoO3.
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9.
On the calculation of activation energies using a modified Kissinger method   总被引:2,自引:0,他引:2  
Augis and Bennett (J. Thermal Anal. 13 (1978) 283.) [6] recently proposed a modified Kissinger method for determining the activation energy of a transformation. It is shown that the proposed method was, in fact, based upon a modification to the equation for the rate of reaction under non-isothermal conditions. The apparent discrepancy between the proposed method and the original Kissinger method is therefore resolved. The modified rate equation appears to have, at best, only a limited application. However, if the equation should be appropriate for a particular transformation, it is demonstrated that Augis and Bennett's method would be the correct method for determining the activation energy.
Zusammenfassung Von Augis und Bennett (J. Thermal Anal.13, (1978) 283) wurde eine modifizierte Kissinger-Methode zur Bestimmung der Aktivierungsenergie einer Umwandlung vorgeschlagen. Es wird gezeigt, dass die vorgeschlagene Methode tatsächlich in einer Modifizierung der Gleichung für die Reaktionsgeschwindigkeit unter nicht-isothermen Bedingungen ihren Ursprung hat. Die scheinbare Diskrepanz zwischen der vorgeschlagenen Methode und der ursprünglichen Kissinger-Methode wird dadurch behoben. Die modifizierte Geschwindigkeitsgleichung hat bestenfalls nur eine begrenzte Anwendung. Jedoch, bei Eignung dieser Gleichung für eine bestimmte Umwandlung zeigt sich, dass die Methode von Augis und Bennett die richtige Methode zur Bestimmung der Aktivierungsenergie sein kann.

(J. Thermal Anal. 13 (1978) 283.) - . , , , . , . , , , . , , .


The author is indebted to the Senate of the University of Queensland for the award of a University Research Fellowship; and to Professor R. R. Stephens for providing laboratory facilities.  相似文献   

10.
The seeds ofCoronilla scorpioides have yielded a new cardenolidic bioside, which has been called coronillobiosidol and has the structure of 3-O-[O--D-glucopyranosyl-(1 4)--D-glucopyranosyl]-14, 19-dihydroxy-5-card-20(22)-enolide.Khar'kov State Pharmaceutical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 726–728, September–October, 1988.  相似文献   

11.
A new glycoalkaloid, haplosidine, has been isolated from the epigeal part of the plantHaplophyllum perforatum, and its structure has been established as 7-[O--D-glucopyranosyl-(1 3)-2-O-acetyl--L-rhamnopyranosyloxy]-4,8-dimethoxyfuranoquinoline.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 94–97, January–February, 1988.  相似文献   

12.
The crystalline structure, electrical conductivity and pyroelecricity of freshly prepared Hg0.7Cd0.3Te thin film have been investigated in detail.
Zusammenfassung Kristallstruktur, elektrische Leitfähigkeit und Pyroelektrizität einer frisch präparierten Hg0.7Cd0.3Te Filmschicht wurden ausführlich untersucht.

, Hg0.7Cd0.3Te.
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13.
The structure of a triterpene glycoside of the cycloartane series — cycloaraloside D, isolated from the roots ofAstragalus amarus Pall. (Leguminosae) — has been established on the basis of chemical transformations and spectral characteristics. Cycloaraloside D is 20R, 24S-epoxycycloartane-3, 6, 16, 25-tetraol 3-0-[0--L-rhamnopyranosyl-(1 2)--D-glucopyranoside].Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 526–528, July–August, 1991.  相似文献   

14.
The paper deals with the relationship between the crystal and molecular structures of CuSO4.5 H2O, CuSO4.3 H2O and CuSO4.H2O on the one hand, and the stoichiometries of their thermal decompositions on the other. With the use of methods of X ray powder diffractograms, i.r. and electronic spectra, evidence is provided that the intermediates of the thermal decomposition of CuSO4.5 H2O have the same crystal and molecular structures as CuSO4.3 H2O and CuSO4.H2O prepared by other procedures. It is also shown that at temperatures near that of the thermal decomposition, certain, not further identified structural changes take place in CuSO4.5 H2O.
Zusammenfassung Es wird einerseits der Zusammenhang der Kristall- und Molekularstruktur von CuSO4 · 5H2O, CuSO4 · 3H2O und CuSO4 · H2O behandelt und andererseits die Stöchiometrie ihrer thermischen Zersetzung. Mit der Auswertung der Röntgen-Pulverdiffraktogramme, der IR- und Elektronenspektren wurde der Beweis erbacht, da\ die Zwischen-produkte der thermischen Zersetzung von CuSO4 · 5H2O dieselben Kristall- und Molekül-strukturen besitzen, wie auf anderen Wegen hergestelltes CuSO4 · 3H2O bzw. CuSO4 · H2O. Ferner wurde gezeigt, da\ bei Temperaturen in der NÄhe der thermischen Zersetzungstemperatur gewisse, jedoch noch nicht identifizierte StrukturÄnderungen in dem CuSO4 · 5H2O stattfinden.

Résumé L'article examine la corrélation entre les structures cristallines et moléculaires de CuSO4.5 H2O, CuSO4.3 H2O et CuSO4.H2O d'une part et la stoechiométrie de leur décomposition thermique de l'autre. En se servant des méthodes des diffraction des rayons X sur poudre et des spectres infra-rouges et électroniques on montre que les produits intermédiaires de la décomposition thermique de CuSO4.5 H2O ont les mÊmes structures cristallines et moléculaires que celles de CuSO4.3 H2O et de CuSO4.H2O préparées par d'autres procédés. On montre également qu'à des températures proches de celle de la décomposition thermique de CuSO4. 5H2O des changements structuraux non encore identifiés ont lieu.

uSO4 · 52, uSO4 · 2 uSO4 · 2, — . , , , uSO4 · 52 uSO4 · 2 uSO4 · 2, . , , uSO4, · 52 , .
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15.
The interaction of diallylnickel with WS2 produces catalysts whose activity is 10–50 times higher than that of the parent sulfide. The atomic catalytic activity referred to supported nickel is independent of the catalyst type and the sulfur removed in temperature programmed reduction.
, WS2 , 10–50 . , , .
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16.
Eight inorganic substances recommended by ICTA as temperature standard reference materials for DTA and DSC were studied: KNO3, KClO4, Ag2SO4, K2CrO4, quartz, K2SO4, BaCO3 and SrCO3. The content of pure component in each of these substances was determined by classical chemical analysis. The temperatures and the heats of polymorphic transformations of these substances were measured with a Perkin-Elmer DSC-2 differential scanning calorimeter, and DTA studies were performed on a MOM 1500 D Q-derivatograph. The plot heat of transformation by DSCvs. DTA peak area is advanced as a calibration line for the approximate estimation of quantitative DTA effects. The substances studied will be certified as temperature standard reference materials for use in DTA and DSC.
Zusammenfassung Acht von der ICTA als Temperaturstandard-Referenzmaterialien für DTA und DSC empfohlene und im Lande verfügbare Substanzen wurden untersucht: KNO3,KClO4, Ag2SO4, K2Cr2O4, Quarz, K2SO4, BaCO3 und SrCO3. Der Gehalt der Substanzen an diesen Verbindungen wurde klassisch chemisch-analytisch bestimmt. Temperaturen und Enthalpien der polymorphen Umwandlungen wurden mit dem Gerät DSC 2 (Perkin-Elmer) bestimmt, DTA-Untersuchungen erfolgten mittels Derivatograph Q 1500 D (MOM). Eine Darstellung (Umwandlungsenthalpie aus DSC-Messung) über der DTA-peak-Flä-che wird als Eichgerade für die näherungsweise quantitative Bewertung der DTA-Effekte vorgeschlagen. Die genannten Substanzen sollen als Temperaturstandards für DTA und DSC geprüft werden.

(-, -, , , , , ), . . -2 -, Q- 1500 . ( ) — . .
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17.
Two new glycosides of the cholestane series (allosides A and B) have been isolated from the fruit of the cocultivatedAllium suvorovii Rgi. andAllium stipitatum Rgl. (family Liliaceae, local name anzur). The acid hydrolysis of both compounds gave a sterol not previously described, which has been called alliosterol and has the structure of (22S)-cholest-5-ene-1, 3, 16, 22-tetraol, and the product of its dehvdration, which is (16S, 22S)-furost-5-ene-1, 3-diol. Alloside A is the 16-O--D-galactopyranoside, and alloside B the 16-O--D-galactopyranoside 1-O--D-glucopyranoside of alliosterol.Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 231–241, March–April, 1991.  相似文献   

18.
The gas phase pyrolysis of azoisopropane has been investigated in a static system in the temperature range 494–546 K. On the basis of gas chromatographic analysis a mechanism is proposed to account for the experimental results.The rate constant of azoisopropane decomposition can be given by the expression {ie383-1}
494–546o . - . , : {ie383-2}
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19.
The effect of different alkali metal hydroxides on the metallic dispersity and catalytic activity of SiO2–AlPO4 (8020, by mass) supported palladium catalysts has been studied. The reduction by hydrogen transfer of benzylideneacetone and styrene (using cyclohexene and n-octanol, respectively, as hydrogen donors) and the liquid phase reduction of cyclohexene at low pressure (5 bar) in a Parr type reactor have been used as test reactions to follow changes in the catalytic activity.
(SiO2–AlPO4/8020 ). ( n-, , , (5 ) .
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20.
Conventional thermoanalytical curves provide little information on the thermal decomposition of Ca(NO3)2 · CO(NH2)2 · 3 H2O. In contrast from quasi-isothermal-quasi-isobaric thermogravimetric curves the mechanism can easily be interpreted. After the complex melts at 60°C, the solution formed is weight constant up to 135°C in the labyrinth crucible. The solution begins to boil at 135°C and gradually loses water, its boiling point increasing. The solution becomes saturated at 200°C. Thereafter, Ca(NO3)2 · CO(NH2)2 separates out while the boiling point does not change. After the departure of the water, the CO(NH2)2 immediately decomposes and Ca(NO3)2 remains.In an open crucible the above transformation is complicated by decomposition of typeAB (s)=A (s)+B (g) solution evaporation drying of solid residue, surface crust formation, etc. In conventional thermoanalysis the latter processes accompany the above processes (melting-solution formation-loss of water during boiling) which hampers interpretation of the conventional curve.
Zusammenfassung Herkömmliche thermoanalytische Kurven liefern wenig Informationen über die thermische Zersetzung von Ca(NO3)2 · CO(NH2)2 · 3 H2O. Quasi-isotherme/quasi-isobare thermogravimetrische Kurven dagegen ermöglichen leicht eine Interpretation des Mechanismus. Nach dem Schmelzen des Komplexes bei 60°C bleibt das Gewicht der Lösung im Labyrinthtiegel bis 135°C konstant. Die Lösung beginnt bei 135°C zu sieden und verliert zunehmend an Wasser, wobei der Siedepunkt ansteigt. Die Lösung erreicht den Sättigungspunkt bei 200°C. Danach scheidet sich Ca(NO3)2 · CO(NH2)2 ohne weitere Veränderung des Siedepunktes ab. Nach Entfernung des Wassers zersetzt sich das CO(NH2)2 sofort und Ca(NO3)2 bleibt zurück.In einem offenen Tiegel wird die obige Umwandlung durch Zersetzung des TypesAB (s)= =A (s)+B(g), durch Verdampfung der Lösung, durch Trocknung des festen Rückstandes, durch Oberflächenverkrustung usw. kompliziert. Diese Prozesse begleiten bei der herkömmlichen Thermoanalyse die oben erwähnten Vorgänge (Schmelzen-Lösungsbildung-Wasserverlust durch Sieden), wodurch die Interpretation der herkömmlichen Kurven erschwert wird.

(N3)2·(N2)2·3 2O . , - , . 60° 135°. 135° . - 200°. , (N3)2 · (N2)2 . , . , ABpac.=Apac + Bpac., , , .. : — — , .


The authors are indebted to Prof. E. Bulewicz and Prof. E. Pungor for valuable discussions.They thank Mrs. M. Kiss and Miss I. Fábián for technical assistance.  相似文献   

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