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51.
Received February 10, 1997 / Revised version received June 6, 1998 Published online October 9, 1998 相似文献
52.
ABSTRACT Starting with methyl 2-O-cyclohexylcarbamoyl-3,4-O-(2,2,2-trichloroethylidene)-α-D-altropyranoside (1), methyl 4-O-cyclohexylcarbamoyl-2,3-O-(2,2,2-trichloroethylidene)-β-D-gulopyranoside (12), and methyl 6-O-cyclohexylcarbamoyl-2,3-O-(2,2,2-trichloroethylidene)-β-D-gulopyranoside (21), the 6-azido-6-deoxyaltroses 4, 6, 11, the 6-azido-6-deoxy-D-gulose 14, the 4-azido-4,6-dideoxy-D-gulose 20, and the 4-azido-4-deoxy-D-gulose 26 were synthesised via iodinated or tosylated precursors. Additionally, two gluco-configured azides, the 3-azido-3,6-dideoxy-D-glucose (19) and the 3-azido-3-deoxy-D-glucose (25), were obtained besides the desired 4-azido-4-deoxy-D-gulosides 20 and 26, when methyl 6-deoxy-4-O-tosyl-β-D-gulopyranoside (18) and methyl 6-O-cyclohexylcarbamoyl-4-O-tosyl-β-D-gulopyranoside, respectively, were reacted with sodium azide. An X-ray analysis is presented for methyl 2,4-di-O-acetyl-3-azido-3,6-dideoxy-zl-D-glucose (19). 相似文献
53.
54.
W. W. Hager P. M. Pardalos I. M. Roussos H. D. Sahinoglou 《Journal of Optimization Theory and Applications》1991,68(3):499-511
The observation that at leasts constraints are active when the Hessian of the Lagrangian hass negative eigenvalues at a local minimizer is used to obtain two results: (i) a class of nearly concave quadratic minimization problem can be solved in polynomial time; (ii) a class of indefinite quadratic test problems can be constructed with a specified number of positive and negative eigenvalues and with a known global minimizer.The authors thank the reviewers for their constructive comments. The first author was supported by the National Science Foundation Grant DMS-85-20926 and by the Air Force Office of Scientific Research Grant AFOSR-ISSA-86-0091. 相似文献
55.
56.
Boyveau und H. Hager 《Fresenius' Journal of Analytical Chemistry》1881,20(1):152-153
Ohne Zusammenfassung 相似文献
57.
A. Kankainen L. Batist S. A. Eliseev V. -V. Elomaa T. Eronen U. Hager J. Hakala A. Jokinen I. Moore Yu. N. Novikov H. Penttilä K. Peräjärvi A. V. Popov S. Rahaman S. Rinta-Antila P. Ronkanen A. Saastamoinen D. M. Seliverstov T. Sonoda G. K. Vorobjev J. Äystö 《The European Physical Journal A - Hadrons and Nuclei》2006,29(3):271-280
The masses of 80, 81, 82, 83Y, 83, 84, 85, 86, 88Zr and 85, 86, 87, 88Nb have been measured with a typical precision of 7keV by using the Penning trap setup at IGISOL. The mass of 84Zr has been measured for the first time. These precise mass measurements have improved Sp and QEC values for astrophysically important nuclides. 相似文献
58.
P. Soltsien Traub Wallach S. Levy H. Hager Schimmel & Co. Fritzsche Weppen Lüder C. Barenthin N. Waeber und G. Heppe 《Fresenius' Journal of Analytical Chemistry》1887,26(1):752-756
Ohne Zusammenfassung 相似文献
59.
Transport in Porous Media - 相似文献
60.
Bend manholes of sewers with 45° deflection angles are considered. Previous results are reconsidered by introducing the so-called
bend extension. It is demonstrated that the discharge capacity of the 45°- and the 90°-bend manholes is identical if the bend
extension, a U-shaped straight downstream portion, is added to the 45° manhole. In addition, the effect of the bend cover
is analyzed as a general means to suppress shock waves. Both bend extensions and bend covers may be added to existing structures
that convey discharge close to or over the design discharge. The hydraulics of bend manholes are analyzed in detail, including
the wave profiles along the inner and the outer bend walls, the complete free surface, the recirculation zone, the pressure
distributions on the walls and flow in the downstream sewer.
Received: 12 March 2001 / Accepted: 10 August 2001 相似文献