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151.
A simple model of a classical break-up process is given in which the correlation E(a,b) of the components A and B of the spins of the two subsystems along directions a and b gives precisely the quantum mechanical result . The model is “local”, but the normalization procedure of correlation functions in terms of “hidden variables” is different from that used in deriving Bell's inequalities. A discretization procedure of the classical spins is then given which reproduces fully the dichotomous quantum mechanical results both for probabilities and for correlation functions. This procedure illustrates particularly clearly the difference between quantum and classical spins and provides a possible intuitive picture for the notion of the “reduction of the wave function”. 相似文献
152.
Bäcklund transformations for several nonlinear field equations in four-dimensional space-time relating two solutions of the same equation (symmetry), or two different equations (dynamical), are given. These transformations can be used to generate new families of solutions and infinitely many conservation laws for nonlinear equations.Bäcklund transformations and solutions of nonlinear equations have been studied extensively in one-space and one-time dimension. We give here a fairly general method for a class of equations in four-dimensional space-time which paves the way for many further generalizations.Supported in part by the U.S. National Academy of Sciences Foundation Grant No. INT 73-20002 A01 (formerly GF-41958). 相似文献
153.
We present, in various limits, analytical expressions for the center-of-mass wave function of a spin-1/2 atom as it is deflected by a Stern-Gerlach apparatus.Work Supported by the Office of Naval Research. 相似文献
154.
The relations betweeb a field FμνM satisfying the usual Maxwell equations and a field FμνD satisfying the symmetric Maxwell-Dirac equations, and the singular potential solving both of these is given. The action principle is formulated in both forms and the reality of the string is shown. A string with spin is constructed by placing electric charges at its end-points. The motion and interactions of the string, the relation between flux and angular momentum quantization and the passage to two-body Hamiltonians are examined. 相似文献
155.
The internal motion of the electron (i.e. Zitterbewegung) takes place in a hyperplane in the Minkowski space orthogonal to the four-vector p
u. For a four-component massless Dirac neutrino it takes place on a two-dimensional plane perpendicular to the three-momentum p, and for a two-component Weyl neutrino it takes place along a straight line perpendicular to p. The kinematical algebras of the compact internal quantum systems are so(5), so(4), and so(2), respectively.On leave from Department of Mathematics, University of Queensland, Australia 相似文献
156.
157.
Optically pure l,1'-binaphthalene-2,2'-diols are very useful compounds for various application[1] such as catalyst ligands for asymmetric synthesis, the starting materials for other chiral binaphthyl catalysts and resolving agents for racemic compounds. Consequently, the preparation of optically pure l,l'-binaphthalene-2,2'-diols are of current interest Recently, new methods of resolution of racemic l,1'-binaphthalene-2,2'-diols utilizing (-)-(lR)-menthyl chloroformate as the derivatization agent have been developed[2,3]. To determine the optical purity of these 1,1'-binaphthalenes, it is necessary to develop a convenient and reliable method for the detection of each stereoisomers. 相似文献
158.
气相色谱-质谱法测定艾叶挥发油中化学成分 总被引:1,自引:0,他引:1
采用水蒸气蒸馏法提取艾叶的挥发油,用气相色谱-质谱法分离和鉴定挥发油成分,并用归一化法测定其相对含量。共分离出76个组分,鉴定出59种化合物。其含量占总挥发油组分峰面积的94.3%。贵州遵义产艾叶主要挥发油成分及其含量为1,8-桉叶油素(22.19%)、樟脑(10.39%)、绿花白千层醇(6.57%)、蒿醇(4.95%)、L-龙脑(4.88%)、α-松油烯(3.98%)、蒿酮(3.44%)、顺式桧烯水合物(3.36%)、4-松油醇(2.68%)、菊油环酮(2.51%)、β-崖柏酮(2.41%)、1-松油醇(2.32%)和丁香酚(2.26%)等。 相似文献
159.
Xiang Rui JIANG Lei AO Chang Xin ZHOU Lei Xiang YANG Hai Bo LI Xiu Mei WU Hua BAI Qi Jun ZHANG Yu ZHAO Department of Traditional Chinese Medicine Natural Drug Research College of Pharmaceutical Sciences Zhejiang University Hangzhou Zhejiang Hisun Naturelite Pharmaceutical R&D Co. Ltd. Hangzhou 《中国化学快报》2005,16(9):1189-1192
As a highly selective and potent acetylcholinesterase(AChE)inhibitor,territrem B wasisolated by Ling et al.from a strain of Aspergillus terreus in19791,2.Zhao et alreported mimic preparation of territrem B analogues from triterpenoids and found thatthe enone moiety and aromatic ring played important roles in their syntheticcompounds3,4.To further detect essential pharmacophors for AChE inhibitors,wesimplified the A/B ring system of territrem B and synthesized a number of pyranonepharmacop… 相似文献
160.
Lidija Urbas Boštjan Košir Matjaž Peterka Boris Pihlar Aleš Štrancar Miloš Barut 《Journal of chromatography. A》2011,1218(17):2432-2437
Monoliths are chromatographic stationary phases, which were specially designed for efficient purification of large biomolecules, like proteins, viruses and DNA. In this work, the small scale monolithic butyl (C4) and styrene-divinyl benzene (SDVB) columns were applied for reversed phase analyses of various degraded influenza viruses. The binding of the HA1 subunit of haemagglutinin to the monolithic columns was confirmed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and the Western blot. The working linear range was determined as 1.60 × 1010 viral particles/mL to at least 1.64 × 1011 viral particles/mL, the limit of detection was found to be 2.56 × 109 virus particles/mL and the limit of quantification was 5.12 × 109 virus particles/mL. The analytical HPLC method developed with the H1N1 virus was also applicable for the analytics of the HA1 subunit of H3N2 influenza virus and the influenza B virus. 相似文献