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71.
Abachi S Abbott B Abolins M Acharya BS Adam I Adams DL Adams M Ahn S Aihara H Alitti J Álvarez G Alves GA Amidi E Amos N Anderson EW Aronson SH Astur R Avery RE Baden A Balamurali V Balderston J Baldin B Bantly J Bartlett JF Bazizi K Bendich J Beri SB Bertram I Bezzubov VA Bhat PC Bhatnagar V Bhattacharjee M Bischoff A Biswas N Blazey G Blessing S Boehnlein A Bojko NI Borcherding F Borders J Boswell C Brandt A Brock R Bross A Buchholz D Burtovoi VS Butler JM Casey D Castilla-Valdez H 《Physical review letters》1995,75(4):618-623
72.
Jamil Hantash Alan Bartlett Georges Dénès Abdualhafeed Muntasar Philip Oldfield 《Hyperfine Interactions》2005,166(1-4):373-378
A new method of preparation of high performance fluoride ion conductor, BaSnF4, by water leaching of newly discovered barium tin(II) chloride fluorides, has been designed, and the materials have been studied and compared to the solid prepared by the usual dry method. The unit-cell parameters and crystallite dimensions were found to vary with the method of preparation. In addition, the crystallite dimensions were found to be highly anisotropic for the samples obtained by the wet method. The Mössbauer spectrum is made of a large tin(II) quadrupole doublet, and a broad tin(IV) oxide peak due to surface oxidation. The tin(II) spectrum is in agreement with covalently bonded tin(II) having a strongly stereoactive lone pair. An unusually high dependence of the quadrupole splitting at low temperatures was observed (5.8 times larger than for α-SnF2). 相似文献
73.
Our diatomic coupled cluster method with numerical orbitals has been applied to the Ne atom. Second, third, and full fourth order MBPT correlation corrections as well as coupled cluster correlation energies are reported. 相似文献
74.
75.
This study investigates the effect of pressure and temperature on crude oil vaporization using first approximation thermal analysis. Developed here is a technique for quantifying the vaporization of fractions of a crude oil using an experimentally obtained thermogravimetric (TG) curve of the crude.The initial data utilized is the weight loss versus temperature values at atmospheric pressure, together with physical property data and equilibrium constant,k values.The results of this study allow the estimation of the volume of oil distilled underground when steam is injected into oil reservoirs at varying pressures and temperatures to recover crude oil.
相似文献
Zusammenfassung Diese Studie untersucht in erster Näherung mittels Thermoanalyse den Einfluß von Temperatur und Druck auf das Verdampfen von Rohöl. Es wird eine Methode zur quantitativen Bestimmung des Verdampfens von Rohölfraktionen entwickelt, die auf einer experimentell ermittelten thermogravimetrischen (TG) Kurve des Rohstoffes basiert. Als Anfangswerte werden die von der Temperatur abhängige Massenabnahme (unter Normaldruck) zusmmmen mit physikalischen Eigenschaften und der Gleichgewichtskonstantek verwendet. Die Ergebnisse dieser Untersuchung erlauben das Abschätzen des Umfanges des Öldestillationsrückstandes, insofern zur Gewinnung des Rohols Dampf in die Ölreservoir injeziert wird.
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76.
L. Bartlett W. Klyne N. J. Dastoor H. Schmid J. Hrbek G. Snatzkec 《Helvetica chimica acta》1971,54(5):1238-1254
The chiroptical properties (CD. and ORD.) of four stereoisomeric yohimbanes ( 1–4 ) and the corresponding 17-keto derivatives 5–8 have been studied. The aromatic and the ketonic Cotton effects have been considered in terms of the appropriate Sector and Octant Rules, respectively. Positively charged nitrogen makes an ‘anti-octant’ contribution to the ketonic Cotton effect. The chiroptical properties, the NMR. spectra and dehydrogenation reactions with mercuric acetate together indicate the presence of a C/D-trans-quinolizidine system in all the compounds studied, except those of the pseudo series ( 3 and 7 ), in which a C/D-cis-quinolizidine system is present. An explanation of the unexpectedly slow dehydrogenation of the 3-epi-allo compounds 4 and 8 is suggested. Conformational analysis of the results of equilibration experiments on pairs of 3-epimeric compounds (in both glacial acetic acid at 145° and in K-t-butylate at 211°) leads independently to conclusions which agree with those drawn from the physical methods. The great differences between the equilibrium positions of the free bases and the protonated forms are due to the presence in the latter cases of oriented ion pairs R3N+H…??O2CCH3. 相似文献
77.
The growth of ice crystals in an electric field 总被引:5,自引:0,他引:5
John T. Bartlett Anthony P. van den Heuval Basil J. Mason 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1963,14(5):599-610
Zusammenfassung Das Wachstum von Eiskristallen in einer Diffusionswolkenkammer wird durch ein elektrisches Feld von über 500 V/cm wesentlich geändert. Die Kristalle wachsen sehr schnell in Form langer, dünner Nadeln. Die Ursache des beschleunigten Wachstums ist noch nicht völlig erkannt; aber die Beobachtungen stimmen mit der Hypothese überein, dass die Kristalle durch Einbau von neutralen Wassermolekülen wachsen. 相似文献
78.
The accuracy of RPA is tested semi-empirically by comparison with full Cl. 相似文献
79.
Abstract— Single-strand breaks are produced in the phosphodiester backbone of ultraviolet-light-irradiated 5–bromodeoxyuridine-containing DNA (BU-DNA) after treatment with alkali. No radiation dependent breakage is observed in thymine-containing DNA (thy-DNA). The relative yields of breaks terminated by 5'-hydroxyl and 5'-phosphate groups was determined by measuring the rate of phosphorylation achieved with polynucleotide kinase in BU-DNA single strands before and after treatment with alkaline phosphatase. The ratio of 5'-phosphate to 5' hydroxyl groups ranged from 2.3 to 2.9 in different experiments. When cysteamine was present during irradiation no new end groups were produced.
In order to identify the nucleoside(s) at the 5'-termini, phosphate groups were removed with alkaline phosphatase and the 5'-hydroxyl groups were phosphorylated with polynucleotide kinase. Electrophoresis of enzymatic digests showed a single32 P-labeled component migrating more rapidly than any of the four usual 5'-mononucleotides. Upon column chromatography this component resolved into a major peak coincident with 5'-dUMP and a lesser unidentified constituent. No 5'-dBUM32 P was observed among these nucleotides. 相似文献
In order to identify the nucleoside(s) at the 5'-termini, phosphate groups were removed with alkaline phosphatase and the 5'-hydroxyl groups were phosphorylated with polynucleotide kinase. Electrophoresis of enzymatic digests showed a single
80.