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81.
Jan Saxl Saharon Shelah Simon Thomas 《Transactions of the American Mathematical Society》1996,348(11):4611-4641
We classify the sequences of finite simple nonabelian groups such that has uncountable cofinality.
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Simon G. Bott Duddu Raja Gopal Annavajhula Durga Prasad Alan P. Marchand 《Journal of chemical crystallography》1993,23(12):1013-1017
The structure of a compound derived from a symmetrical cage diketone in which one of the ketone C=O groups has been converted into a ketal is reported. An investigation into reasons for the selective functionalization resulted in the isolation of acis, cisoid, cis linear triquinane derivative in which both ketones are converted to ketals that share a transannular oxygen atom. Crystal data:2, monoclinic,P21/c,a=7.6298(9),b=7.673(3),c=22.125(3)Å,=97.59(1)°,V=1283.9(5)Å3, andR=0.048 (1001 reflections);4, triclinic,P¯1,a=7.3864(9),b=9.6362(9),c=10.3889(9)Å,=75.749(6),=76.300(8), =83.100(8)°,V=694.8(4)Å3, andR=0.088 (1284 reflections). 相似文献
86.
Y. A. Gordon V. Jakšić S. Molčanov B. Simon 《Communications in Mathematical Physics》1993,157(1):23-50
We investigate spectral properties of random Schrödinger operators H = - + n()(1 + |n|) acting onl
2(Z
d), where n are independent random variables uniformly distributed on [0, 1].Research partially supported by a Sloan Doctoral Dissertation Fellowship and NSERC under grant OGP-0007901Research partially supported by NSF grant DMS-9101716 相似文献
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den Brok MW Nuijen B Miranda E Floriano P Munt S Manzanares I Beijnen JH 《Journal of chromatography. A》2003,1020(2):251-258
ES-285 x HCl [(2S,3R)-2-amino-3-octadecanol hydrochloride] is a novel investigational anticancer agent, which has shown in vitro and in vivo cytotoxic activity against various tumor cell lines with selectivity for certain solid tumors. The pharmaceutical development of ES-285 x HCl warranted the availability of an assay for the quantification and purity determination of ES-285 x HCl active pharmaceutical ingredient (API) and its pharmaceutical dosage form. A liquid chromatographic method (LC) comprising of derivatisation of ES-285 x HCl with phenylisothiocyanate and UV-detection was developed. The method was found to be linear, precise and accurate. The assay also proved selectivity as determined by analysing ES-285 x HCl in combination with 15 analogues and in combination with hydroxypropyl-beta-cyclodextrin, the excipient used in the lyophilised pharmaceutical dosage form. Stress testing showed that the degradation products were separated from the parent compound, confirming its stability indicating capacity. The method was found robust as determined with design of experiments (DoE), which made it possible to predict system suitability responses in worst case experimental conditions and to define criteria for system suitability testing. 相似文献
89.
We have investigated the dielectrophoretic assembly of colloidal gold, carbon black, and carbon nanotubes into electrical wires. The resulting microwires have diameters less than 1 microm, with lengths ranging from 5 microm to 3 mm. Current-voltage curves for these wires indicate an ohmic response, where the resistance is determined by the type of colloid and by the frequency of the alternating field used to grow the wires. The predicted frequency dependence of dielectrophoresis is confirmed by experiment. Measurements of the threshold voltage for initial wire growth are also presented. These experiments demonstrate that a variety of nanoparticles can be assembled into microwires for sensor applications. 相似文献
90.
Application of the LCAO-MO-SCF- method to conjugated hydrocarbons leads with the effective nuclear Slater's charges, Zeff = Zeff = 3.25 to electronic transitions higher than experimental ones by about 50%.We show that in the case of all trans linear polyenes and fulvene, one may obtain satisfying results by the same method, without any reference to experience, by taking Zeff = 3.0 Zeff = 3.55. There the effective nuclear charges are near of these of the valence state of carbon V
41s2t1t2t32ptz:Zeff = 2.971 Zeff = 3.382 [10]. 相似文献