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1.
Zusammenfassung Für die Elemente Neon, Natrium, Magnesium, Aluminium und Silizium werden mit einem quantenmechanischen Variationsverfahren unter Verwendung einer minimalen STF-Funktionenbasis Röntgenübergänge vom Typ K 1L1L2 berechnet und den K -Satellit-Linien , , 3, 3 and 4 zugeordnet.
Relation between K -Satellits and X-ray-transitions of the type K 1 L 1L 2 for Ne, Na, Mg, Al and Si
STF-Calculations are reported for X-ray-transitions of the type K 1L1L2 for Ne, Na, Mg, Al and Si. It is shown that these transitions are correlated with the K -satellits , , 3, 3 and 4.


Die Wellenfunktionen können auf Anfrage zur Verfügung gestellt werden.  相似文献   

2.
Conclusions Trisaccharide-D-glucopyranosyl-(14)--L-rhamnopyranosyl-(1 3)-D-galactose was synthesized by using, 2-O-isopropylidene-4,6-O-ethylidene--D-galactopyranose for producing 1 3-rhamnosylgalactose, linkage.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1609–1613, July, 1977.  相似文献   

3.
The kinetics of oxidation of isobutyraldehyde with aqueous chlorine has been investigated in 11.6 vol. % aqueous acetic acid. The reaction is first order with respect to both substrate and chlorine. Molecular chlorine is the principal oxidant. The influence of various factors, e.g. ionic strength, inorganic salts, D2O and temperature on the initial rate has been studied. The activation parameters have been calculated and a possible mechanism is suggested.
11,6% . , . . ( , , D2O) . .
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4.
Kinetic regularities in the reaction of triphenyl phosphite ozonide with several thioacetals in CH2Cl2 solution at –15°C have been studied. The consumption rate of ozonides is described by the kinetic equation W=k0[(C6H5O)3P·O3]+k1[(C6H5O)3P·O3][R1R2C(SR3)2] Rate constants k0 and k1 for the thioacetals: (CH3H7S)2CH2, (C6H5S)2CH2, (C6H5CH2S)2CH, (n=C12H25–S)2CH2, (C3H7S)2C(H)CH3, (C3H7S)2C(H)C6H5, (C3H7S)2C(CH3)C6H5 and (C3H7S)2C(H)C10H9, increases with increasing the electron-donating power of subtituents Ri.
CH2Cl2 –15°C. : W=k0[(C6H5O)3P·O3]+k1[(C6H5O)3P·O3][R1R2C(SR3)2] k0 k1 (C3H7S)2CH2, (C6H5S)2CH2, (C6H5CH2S)2CH2, (n-C12H25S)2CH2, (C3H7S)2C(H)CH3, (C3H7S)2C(H)C6H5, (C3H7S)2C(CH3)C6H5, (C3H7S)2C(H)C10H9. .
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5.
Johnson-Mehl equation is written as d/dt=k n t n–1 (1–) where is the degree of reaction,t time andn a constant. Use of this equation in kinetic analysis present problems because of the presence of a t term on the right hand side. The equation is not a true kinetic equation andk is not a true rate constant.This paper presents a brief discussion on the use of this equation as such or in a modified form and also indicates the proper procedure for evaluating kinetic parameters correctly. Some experimental data on the reduction of Fe2O3 to Fe3O4 have been used to test the mathematical procedure proposed. This reaction is known to follow the typical trend described by Johnson-Mehl equation.
Zusammenfassung Die Johnson-Mehl-Beziehung lautet:d/dt=k n t n–1(1–) mit der Reaktionskoordinate, der Zeitt und der Konstanten. Eine Anwendung dieser Gleichung in der kinetischen Analyse verursacht Probleme, da auf der rechten Seite der Gleichung ein t-haltiger Ausdruck steht. Die Gleichung ist keine wirkliche kinetische Gleichung undk ist keine wahre Geschwindigkeitskonstante.Diese Arbeit beschreibt eine kurze Diskussion der Anwendung dieser Gleichung in dieser oder einer modifizierten Form und beschreibt, wie korrekte kinetische Parameter erhalten werden können. Zum Testen des vorgeschlagenen mathematischen Verfahrens wurden einige experimentelle Daten der Reduktion von Fe2O3 zu Fe3O4 benutz. Diese Reaktion ist bekannt, dem typischen, durch die Johnson-Mehl-Gleichung beschriebenem Trend zu folgen.


Dr. S. B. Sarkar wishes to acknowledge the financial support of the Commonwealth Commission (U.K.) and the experimental facilities provided by the Imperial College of Science and Technology, London U.K.  相似文献   

6.
The kinetics of metallotropy of the 3,6-di-tert-butyl-2-(triphenylstannyl)oxyphenoxyl radical has been studied by ESR. The correlation between chemical exchange time ex, solvent polarity, and longitudinal relaxation time of the solvent corresponds to the model of a process controlled by molecular dynamics. A linear relation between ex and correlation time c for reorientation movements of the radical is found: ex = · c. The coefficient depends on the dielectric properties of the solvent.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 410–413, March, 1994.This work was supported by the Russian Foundation for Basic Research, project No. 93-03-4372.  相似文献   

7.
Reasonable structural models are proposed for two intercalated compounds of-Zr(HPO4)2·H2O (-ZrP), one with 2,2-bipyridyl (A) and another one with 1,10-phenanthroline (B). The models are derived by considerations of the unit-cell geometry changes undergone by-ZrP upon insertion of the organic molecules and on a set of general criteria of structural analysis, already developed by us and called the comparison method. If it is assumed that the water molecules in A and B keep the positions they have in-ZrP, as fixed by their links to the phosphate-OH groups, the inserted molecules, while obeying the general conditions of optimum packing, establish interactions of the hydrogen-bonding type with the water molecules. This modeling gives for A and B a possible structural explanation to the maximum number of inserted molecules of the two species, as fixed by their stoichiometry.  相似文献   

8.
Résumé On a modifié la méthode différentielle pour le calcul des paramètres cinétiques des réactions de décomposition thermique du type: A(s) B(s) + C(g), en utilisant les données de l'analyse thermodifférentielle. En effectuant le calcul des paramètres cinétiques des réactions de déshydratation de l'oxalate de calcium monohydraté et de décomposition du carbonate de calcium on obtient des résultats qui concordent d'une manière satisfaisante avec ceux obtenus par d'autres méthodes.
A modification of the differential method is presented in order to evaluate the kinetic parameters of thermal decomposition reactions of the type A s B s + +Cg, using differential thermal analysis (DTA) data. The kinetic parameters calculated for the dehydration and decomposition of calcium oxalate and carbonate agree satisfactorily with those mentioned in the literature.

Zusammenfassung Es wird über eine Abänderung der Differentialmethode zur Errechnung der kinetischen Parameter von thermischen Zersetzungsreaktionen des Typs A(s) B(s) + C(g) mit Hilfe von differentialthermoanalytischen Daten berichtet. Die am Beispiel der Dehydratation des Calciumoxalat-Monohydrats und der Zersetzung des Calciumcarbonats erhaltenen Ergebnisse der auf angegebene Weise durchgeführten kinetischen Berechnungen stimmen gut mit den nach anderen Methoden erhaltenen Resultaten überein.

A(s) (s) + C(g), (). , , , .
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9.
Catalytic properties of V2O5/SiO2 in benzene oxidation by N2O were examined. Sodium additive was shown to affect the catalyst operation stability.
V2O5/SiO2 N2O. .
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10.
Zusammenfassung DieRaman- und Infrarotspektren der aus, -Dialkoholen und, -Dicarbonsäuren synthetisierten linearen, aliphatischen Polyester des Typs-((CH2) x -O-CO-(CH2) y -CO-O)-mitx=2, 3,...12 undy=3, 4,...12werden diskutiert und mit den Spektren der entsprechenden Dialkohole und Dicarbonsäuren verglichen. Aus den charakteristischen Unterschieden und Übereinstimmungen zwischen den Spektren der verschiedenen Polyester einerseits und den Spektren der Monomeren und Polyester andererseits wird der Einfluß der Estergruppe auf die Schwingungen der Methylengruppen und des Molekelgerüstes untersucht.
Summary TheRaman and infrared spectra of linear aliphatic polyesters of the type-((CH2) x -O-CO-(CH2) y -CO-O)-which were synthesized from, -hydroxyalkanes and, -carboxyalkanes, were discussed and compared with the spectra of the corresponding diols and dicarboxylic acids. The characteristic changes between the spectra of different polyesters on the one side and the spectra of the monomers and polyesters on the other side made it possible to study the influence of the ester group on the vibrations of the monoethylene groups and the skeletal.
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11.
m-Xylene conversion was studied over dealuminated Y type zeolites in hydrogen forms, SiO2 to Al2O3 ratios were varied from 4.86 to 12.95.
- . SiO2/Al2O3 4,86 12,95.
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12.
The rate constants and activation energies of bimolecular deuterium exchange in the systems: C5H5SD+i-C3H7SH and t-C4H9SD+i-C3H7SH in dilute C6H12 solutions have been established. The concerted H-transfer inside the cyclic dimer with two H-bonds formed in these systems is probably the rate-limiting step. The rate constant for H-transfer inside the cyclic dimer is independent of the acidic properties of the thiols.
: C6H5SD+i-C3H7SH -C4H9SD+i-C3H7SH C6H12. -, , , . .
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13.
The reactions of TMA4Ge4S10 (TMA=tetramethylammonium), Cu(NO3)23H2Oand 4,4-bipy under hydrothermal environment result in the formation of (H2bipy)2Ge4S10(bipy)7H2O (1), which has been structurally characterized by single crystal X-ray analysis. The 3-D structure of 1 can be viewed as an inorganic-organic hybrid supramolecular hydrogen-bonding (hydrogen bonds: O–HO, N–HN, C–HO, N–HO, and O–HS) and - stacking network containing Ge4S4– 10 clusters and novel [H2bipybipyH2bipy] trimers.  相似文献   

14.
IR spectra of oxygen adsorbed on SnO2 with and without lattice defects have been studied. At low temperatures oxygen is adsorbed on defect SnO2 in two forms of O 2 . This supports the earlier results obtained by ESR. The low-temperature forms of adsorbed oxygen (unrevealed in ESR spectra) were detected on defectless SnO2. High-temperature forms of adsorbed oxygen appear in the IR-spectra as bands due to vibrations of the cation-oxygen bond.
- SnO2. , O 2 , . SnO2 .
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15.
A thermodynamic study is presented for the simultaneous synthesis of C1–C4 alcohols from synthesis gas. The equilibrium composition was calculated for the gaseous mixture containing Co, H2, CH3OH, C2H5OH, C3H7OH, n-C4H9OH and H2O. Operating industrial conditions were specifically considered.
C1–C4 -. , CO, H2, CH3OH, C2H5OH, C3H7OH, -C4H9OH H2O. .
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16.
Zusammenfassung Aus Mono-und Dihalogen-essigsäuren bilden sich mitSchiff-schen Basen in Dimethylformamid (DMF) und POCl3 (bzw. POBr3) über labile Addukte -Lactame. Analog reagieren -Chlor-und -Brom-propionsäure.
The reaction of -chloro and -bromo acetic or propionic acids withSchiff bases inDMF in the presence of POCl3 or POBr3 yields -lactames via unstable adducts.
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17.
Five new sulfated derivatives of sokotrasterol and halistanol have been obtained: 24-nor-5-cholane-2,3,6,23-tetraol 2,3,6-tri(sodium sulfate); 24-nor-5-cholane-2,3,6,23-tetraol 2,3,6-tri(sodium sulfate) 23-palmitate; 24,25-dimethyl-5-cholestane-2,3,6-triol 3-(sodium sulfate); 24,25-dimethyl-5-cholestane-2,3,6-triol 6-(sodium sulfate); and 24,25-dimethyl-5-cholestane-2,3,6-triol 2,6-di(sodium sulfate). The inhibiting and membranolytic properties of the polysulfated steroids from sponges and their derivatives have been studied. It has been shown that physiological activity in this series of compounds depends on biphilicity.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 441–445, July–August, 1986.  相似文献   

18.
Whereas 1 1 crystalline complexes have been isolated between borane ammonia and methyl 4,6-O-benzylidene-2,3-dideoxy--d-galactopyranosido [2,3-b]-1,4,7,10,13,16-hexaoxacyclo-octadecane (1), methyl 4,6-O-benzylidene-2,3-dideoxy--d-mannopyranosido [2,3-b] (methyl 4,6-O-benzylidene-2,3-dideoxy--d-mannopyranosido [2,3-k]-1,4,7,10,13,16-hexaoxacyclo-octadecane (3), and (1R,2R,7R,24R)-3,5,8,11,14,17,20,23,26,28-decaoxatricyclo-[21.4.0.02,7]octacosane (4), the hosts, methyl, 4,6-O-benzylidene-2,3-dideoxy--d-mannopyranosido[2,3-b] 1,4,7,10,13,16-hexaoxacyclo-octadecane (2) and 1,4 1,4 3,6 3,6-tetra-anhydro-2,2 5,5-bis-O-oxydiethylenedi-d-mannitol (5) have yielded 2 1 (guest:host) crystalline complexes with borane ammonia as guest. X-ray analyses of the supramolecular structures of BH3NH3 ·1, (BH3NH3)2 ·2, BH3NH3 ·3, BH3NH3 ·4, and (BH3NH3)2 ·5 have been carried out and BH3NH3 ·1, BH3NH3 ·2, and (BH3NH3)2 ·5 have been shown to reduce acetophenone with enantiomeric excesses of 5, 13, and 10% respectively. Supplementary Data relating to this article (atomic coordinates of the hydrogen atoms and thermal parameters) are deposited with the British Library as Supplementary Publication No. SUP 82017 (74 pages).Dedicated to Professor H. M. Powell.  相似文献   

19.
Crystal structure refinement was performed of the metastable modification of glycine (space gr. P21, a = 5.092(2) , b = 6.273(3) , c = 5.384(3), = 113.17(4)°, Z = 2, R = 0.0274). The crystals were obtained by a new method (not described in the literature): they were precipitated from a water solution with the addition of glacial acetic acid. The crystal structure of the glycine modification [space gr. P21/n, a =5.106(1) , b = 11.979(5) , c = 5.463(2) , = 111.75(2)°:, Z =4] was refined for comparison. Transition from the to the modification in a damp atmosphere was revealed, resulting in the formation of a strongly strained crystal of a mosaic structure. The orientation of the crystallographic axes in the newly formed crystal of the modification relative to the axes in the initial crystal of the modification was determined. It is shown that as in glycine, the lengths of the intramolecular C—O bonds in the modification are fairly similar [1.248(2) and 1.253(2) ] and the previously found significant difference between them is most likely due to the errors of the photomethod. A comparative analysis of the crystal structures of the and glycine modifications (glycine zwitterion packings and structure of intermolecular hydrogen bond networks) was performed. Data of the analysis are used to discuss the properties of the glycine modifications, the possible reasons for the stability of the modification in dry air, the difficulties of crystal growth from solutions, and the ease of crystallization of the modification under various conditions.  相似文献   

20.
Zusammenfassung -Äthyl--phenylacetessigester (I) wurde bromiert, der resultierende -Bromacetylphenylbuttersäureester (II) mit NaBH4 zum Bromhydrin (III) reduziert. Umsetzung mit KCN lieferte den -Cyan--hydroxy--phenyl--äthylbuttersäureester (IV), der in Gegenwart vonRaney-Ni zu den beiden stereoisomeren 3-Äthyl-3-phenyl-4-hydroxypiperidonen-(2) (Va) und (Vb) reduziert wurde. Oxydation von (Vb) mit CrO3 lieferte das 3-Äthyl-3-phenylpiperidindion-(2,4) (VI).  相似文献   

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