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11.
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Brick DH Widgoff M Beilliere P Lutz P Narjoux JL Gelfand N Alyea ED Bloomer M Bober J Busza W Cole B Frank TA Fuess TA Grodzins L Hafen ES Haridas P Huang D Huang HZ Hulsizer R Kistiakowsky V Ledoux RJ Milstene C Noguchi S Oh SH Pless IA Steadman S Stoughton TB Suchorebrow V Tether S Trepagnier PC Wadsworth BF Wu Y Yamamoto RK Cohn HO Calligarich E Castoldi C Dolfini R Introzzi G Ratti S Badiak M DiMarco R Jacques PF Kalelkar M Plano RJ Stamer PE Brucker EB Koller EL Alexander G Grunhaus J 《Physical review D: Particles and fields》1990,41(3):765-773
13.
John R. Peterson Tamara J. Winter Hoang D. Do Robin D. Rogers 《Journal of chemical crystallography》1989,19(1):135-145
Structural and conformational information obtained from the crystal structure and solution1H nmr investigations of the title compound are compared. The 4-aryltetralone, C24H24O10, crystallizes as a chloroform solvate in the monoclinic space group, P21/n, witha=12.519(4),b=17.938(6),c=12.534(9)Å,=111.90(5)°, and Dcalc=1.51 g cm–3 forZ=4. The data for this compound were collected at –150°C. Least-squares refinement of 2796 observed [F
o5(F
o)] reflections led to the final agreement index ofR=0.062. A threefold static disorder was observed for one of the carboxyl groups. The second carboxyl group participates in an intramolecular hydrogen bond and is thus ordered. The1H nmr spectrum revealed the title compound to exist as a keto-enol tautomeric mixture in solution. Vicinal hydrogen coupling constant analysis proved reliable in ascertaining B-ring stereochemistry of 2,3-disubstituted-4-aryltetralones. 相似文献
14.
Brown coal from two areas in New Zealand was treated with acids (HF and HCl) to remove the clays. Iron was then introduced into the “cleaned” coal by ion exchange. Mössbauer spectra of the untreated coal, the low temperature ash of the coal, “cleaned” coal and ion-exchanged coal were analysed. From these spectra we conclude that a pair of lines with QS~1 mm s?1 and IS~0.45 mm s?1 is probably due to organically bonded iron. 相似文献
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Schell Daniel J. Walter Pamela J. Johnson David K. 《Applied biochemistry and biotechnology》1992,34(1):659-665
Applied Biochemistry and Biotechnology - The enzymatic digestibility of a pretreated substrate is enhanced by increasing the severity of the pretreatment conditions, apparently because a greater... 相似文献
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Bernard A. Mikrut Krishan K. Khullar Pamela Y. P. Chan John M. Kokosa Ludwig Bauer Richard S. Egan 《Journal of heterocyclic chemistry》1974,11(5):713-718
The reaction of pyridine 1-oxide with 1-adamantanethiol in acetic anhydride produced a mixture of 2- and 3-(1-adamantanethio)pyridines, 1-aeetyl-2-(1-adamantanethio)-3-hydroxy-4-acetoxy-1,2,3,4-telrahydropyridine and the corresponding 3-acetoxyderivative. Pure substances were separated by means of column chromatography on alumina. The tetrahydropyridines were identified by means of their proton magnetic and mass spectra. 4-(1-Adamantanethio)pyridine was synthesized from 4-chloropyridinc and 1-adamantanethiol. The three isomeric (1-adamantanethio)-pyridines were, each, cleaved by concentrated hydrochloric acid to give 1-chloroadamantane and the corresponding pyridinethiol. 相似文献
20.
J. R. Norris L. C. G. Rogers David Williams 《Probability Theory and Related Fields》1987,74(2):271-287
Summary A natural model for a self-avoiding Brownian motion inR
d, when specialised and simplified tod=1, becomes the stochastic differential equation
, where {L(t, x):t0,xR} is the local time process ofX. ThoughX is not Markovian, an analogue of the Ray-Knight theorem holds for {L(,x):xR}, which allows one to prove in many cases of interest that
exists almost surely, and to identify the limit. 相似文献