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排序方式: 共有277条查询结果,搜索用时 15 毫秒
81.
C. Browne R. W. Shaffer E. Wathelet L. Ramcle A. Noll F. Bolz H. Fiedler M. D. Reuben S. Köhler F. Noss H. Sadler A. R. Matthis B. von Possaner A. Weber K. Hang K. Ramse E. Sutermeister E. Richter V. Gruenman W. Brecht E. Helmer L. K. Arnold W. Breeht F. L. Goodall J. M. Jarmus W. R. Willets 《Analytical and bioanalytical chemistry》1935,101(11-12):457-464
82.
This paper considers the problem of the design of an FMS system. An integrated design procedure is outlined, which involves three stages — planning, design and implementation. Within each stage the design decisions to be made are discussed, together with the techniques and skills required to complete each design stage. At each stage, reference is made to the views of other designers and researchers. Finally, the procedure is illustrated through a case study of a miniature FMS designed and installed at the Cranfield Institute of Technology. 相似文献
83.
L. O. Lamm C. P. Browne J. Görres M. Wiescher A. A. Rollefson 《Zeitschrift für Physik A Hadrons and Nuclei》1987,327(2):239-240
The excitation energies of states in20Na near the proton threshold have been measured with the20Ne(3He, t)20Na charge exchange reaction. The possible implications of these states for the stellar reaction rate of19Ne(p,γ)20 Na are discussed. 相似文献
84.
Experimental Techniques - 相似文献
85.
Basically this paper deals with the determination of the radius of starlikeness and radius of univalence of the class of meromorphic
functions of the formg(z)=A/z−Φ(z) forA>0, and where Φ(z) is an analytic function defined in the unit disk whose modulus does not exceed unity. We estimate the radius ofp-valence of functions having the fromh(z)=Φ(z)+a/z
p fora>1,p≧1, and also estimate the radius of starlikeness of certain Blaschke products which is also given as a function of the minimum
modulus function. We discuss the question of sharpness of the results and mention some open problems. 相似文献
86.
The 13C spectra of a series of 21 cis-decalins, 17 of which bear 10-methyl substituents, have been recorded to examine geometrical and conformational effects on the 13C shieldings. Although the data for a few of the simpler examples have been reported, these compounds were examined to obtain results for a common medium and temperature. All of the derivatives are conformationally mobile and their spectra were examined as a function of temperature to obtain shieldings representative of the slow exchange limit. The examples include compounds which populate both available chair-chair conformations equally, some which exhibit a preference for one of these conformations and some which exist essentially in a single conformation. The data for the latter group combined with the observed temperature dependencies and results for other decalin systems led to specific assignments for each carbon. The internal consistency of the entire body of data offers strong support for these assignments. The conformational preferences observed for a number of decalones and Δ3-10-methyldecalin derivatives are discussed. 相似文献
87.
Paul A. Binding Patrick J. Browne Bruce A. Watson 《Journal of Mathematical Analysis and Applications》2002,271(2):383-408
Inverse Sturm-Liouville problems with indefinite weight are considered. Theorems analogous to those of both Hochstadt and Gelfand-Levitan are proved. As a sample result, under suitable symmetry conditions, we show that half of one spectrum suffices to determine the potential function uniquely. 相似文献
88.
The conditions for infrared convergence and asymptotic freedom are investigated for a system in which (in order to produce a spontaneous breakdown) a supersymmetric matter-matter interaction is added to the supersymmetric Yang-Mills Lagrangian. It is found that, in contrast to conventional theory, the conditions imposed by the asymptotic freedom of the matter-matter interaction are not stringent, and are automatically satisfied for adjoint representations. The conditions for infrared convergence are also not too stringent. However the joint conditions for asymptotic freedom and infrared convergence turn out to be quite stringent. Nevertheless, a model is proposed which, subject to some reservations, appears to satisfy the joint conditions. 相似文献
89.
90.
Jaap J.D. de Jong Theodora D. Tiemersma-Wegeman Wesley R. Browne Kingo Uchida Ben L. Feringa 《Tetrahedron》2008,64(36):8324-8335
The synthesis and characterisation of a series of chiral and achiral low molecular weight organogelators (LMWGs) based on bis-amide substituted dithienylethene photochromic switches is reported. The LMWGs gelate a range of solvents depending on the specific functionalisation of the hydrogen bonding amide groups. In mixtures of chiral and achiral LMWGs the stereochemical outcome of the chiral aggregation is determined by the chiral LMWG molecules in most cases. However, for the first time we demonstrate that the stereochemical outcome of the aggregation can be influenced by the achiral LWMG molecules in some cases. Furthermore specific π-π (and/or van der Waals) interactions of chiral LMWGs 1-3o with the solvent allow the solvent to influence the control of chirality of aggregation. This influence of the solvent has a dramatic effect on whether four- or two-gel states are available. 相似文献