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101.
A new sufficient condition for the variance of a unimodal distribution in ?a, b? to have the least upper bound is derived. This condition is more general than the condition found by Jacobson (1969). A new proof that the least upper bound for all unimodal distributions in ?a, b? is is also given. These results are used to construct a new estimator of the variance of such distributions. 相似文献
102.
103.
104.
Michael T. Takemori Dean S. Matsumoto 《Journal of Polymer Science.Polymer Physics》1982,20(11):2027-2040
Polycarbonate exhibits an extraordinary crack-tip plastic zone under certain fatigue loading conditions. During discontinuous growth (multiple load cycles per crack jump), the plastic zone consists of a leading craze and a pair of sharply delineated shear bands, which together look like the Greek letter epsilon. The kinetics of the development of the epsilon plastic zone and the nature of the transition from discontinuous growth to a shear fatigue fracture mode are discussed. 相似文献
105.
Mills Dean III 《Experimental Mechanics》1977,17(8):303-307
New materials and techniques are described for using vulcanized rubber to protect strain gages installed on the components of a controllable-pitch propeller (CPP) system of a Navy destroyer. Strain gages protected by vulcanized rubber have survived many months of full-scale sea trials of the CPP system. 相似文献
106.
Dean P. Stull Thomas A. Scales Randy Daughenbaugh Neil A. Jans David T. Bailey 《Applied biochemistry and biotechnology》1995,54(1-3):133-140
Taxol® (paclitaxel) has been hailed by many as the most promising new cancer treatment in two decades. The FDA requires that paclitaxel intended for human consumption be obtained only from the bark ofTaxus brevifolia, the Pacific yew. As this may become increasingly uneconomical, new strategies must be explored to ensure the continued availability of taxol and related molecules. This article examines the planning that must be engaged in and the contingencies that must be prepared for in this changing arena. 相似文献
107.
T. D. J. Perkins J. E. J. Mills P. M. Dean 《Journal of computer-aided molecular design》1995,9(6):479-490
Summary Steric complementarity is a prerequisite for ligand-receptor recognition; this implies that drugs with a common receptor binding site should possess sterically similar binding surfaces. This principle is used as the basis for an automatic and unbiased method that superposes molecules. One molecule is rotated and translated to maximize the overlap between the two molecular surface volumes. A fast grid-based method is used to determine the extent of this overlap, and this is optimized using simulated annealing. Matches with high steric similarity scores are then sorted on the basis of both hydrogen-bond and electrostatic similarity between the matched molecules. Flexible molecules are treated as a set of rigid representative conformers. The algorithm has correctly predicted superpositions between a number of pairs of molecules, according to crystallographic data from ligands that have been co-crystallized at common enzyme binding sites. 相似文献
108.
109.
The theoretical model for multiple bound excitons (MBE) recently introduced by Dean et al1 is used to discuss uniaxial stress effects in silicon. The fine structures observed in MBE spectra for SiC and Si are qualitatively strikingly similar. However, the interpretation of the strongest features in terms of a specific model for excited states suggested by Kirczenow2 and Thewalt3 is not valid for SiC. 相似文献
110.
Richard E. Smalley Lennard Wharton Donald H. Levy Dean W. Chandler 《Journal of Molecular Spectroscopy》1977,66(3):375-388
The fluorescence excitation spectrum of the transition in s-tetrazine has been observed and measured. The sample was cooled to a rotational temperature of <1 K by expansion in a supersonic free jet. In this way the rotational structure arising from asymmetry split low J lines could be observed. The rotational A and B axes of the 2H112C214N4 isotope were observed to interchange upon electronic excitation and a theory describing the effect of this interchange upon the optical selection rules has been developed. Analysis of the resolved rotational structure suggests that the geometry change upon electronic excitation is smaller than that deduced from previous analysis of the room temperature optical spectrum. 相似文献