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BBAOYu- Min FUGe- Yan QIJian- Ping(包玉敏 付戈妍 齐建平 ) (4 - 473 )……………………………………………………………BIL i  YAN GYa- L ing  LUOKang- Bi  LIUMou- Sheng(毕 莉 杨亚玲 罗康碧 刘谋盛 ) (2 - 2 2 9)………………………………CCAIJi- Jie(蔡继杰 ) (4 - 5 3 9)……………………………………………………………………………………………………………………CAIWen- L ian  HEH ong LIUJia- Ming(蔡文联 何 红 刘佳铭 ) (5 - 616)…………………………………………………………CH …  相似文献   

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We prove the decomposition formula for the -invariant of the compatible Dirac operator on a closed manifoldM which is a sum of two submanifolds with common boundary.Research partially supported by NSF  相似文献   

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This report reviews the recent progress that has been made toward understanding the necessary-for-life chemistry that took place on the prebiotic Earth, and that led to the appearance of the ht living cells. This understanding is based on the simulation, in the laboratory, of conditions analogous to those presumed (on geological and astronomical evidence), to have been present on the primitive Earth. Such research has led to the production of many of the classes of compounds that are key constituents of our contemporary biology. It has also led to the knowledge that abiogenetically produced organic compounds have an intrinsic tendency to assume the forms and the aggregations that are found in living cells. The report concludes with a summary of the exciting new finds of ‘biological’ molecules in interstellar space.  相似文献   

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The isomeric 1- and 2-naphthyl acetates (acetoxynaphthalenes) are at the confluence of diverse concepts, techniques and classes of organic compounds. Summing the results of literature measurements of the enthalpy of formation of their solids and of our new sublimation enthalpies reported herein, we derive gas phase enthalpies of formation of ?209.9 ± 1.4 and ?213.3 ± 1.3 kJ mol?1 respectively. This corresponds to 2-naphthyl acetate being more stable than its 1-isomer by 3.4 ± 1.9 kJ mol?1. We also performed MP2(full)/6-31G(d) calculations on these species, resulting in enthalpies of formation of ?212.9 ± 3.9 and ?212.2 ± 3.9 kJ mol?1 for 1- and 2-naphthyl acetate and a difference of ?0.7 kJ mol?1 respectively in satisfactory agreement with the above experimental results.  相似文献   

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We construct the renormalization operation of the expressions connected with the large field regions. This operation, denoted by , removes the main obstacle to prove the ultraviolet stability of four-dimensional gauge field theories. The proof will be completed in the second part of this paper.Research supported in part by the National Science Foundation under Grant DMS-86 02207  相似文献   

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Recent data for the variation of the diffusivity of hydrogen in b.c.c. VTi solid solutions with Ti-concentration and temperature have been analyzed in terms of the cell model for such ternary solid solutions. The data have been shown to be compatible with this model and a simple cell energy spectrum involving H-metal interactions which are linearly dependent upon the Ti-concentration.It is shown that the interaction energies deduced from the kinetic behavior of the system are in good accord with thermodynamic data for the VH and TiH terminal solid solutions.  相似文献   

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The compression texture of -tin, produced by compressing the sample at temperatures of 20° C, –80° Cand –180° C,was measured. Measurement was carried out by the reflection method on a Schulz diffractometer by measuring the pole f'gures of the (200)and (101)planes. The results of the measurements show the produced, texture to be considerably dependent on the temperature.  相似文献   

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Measurements were made of the rolling texture of -tin which is produced by rolling the sample at a temperature of 20 °C and in the temperature interval –80°C–60 °C and –180 °C–110 °C.  相似文献   

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I review the scientific production of Eberhard K.U. Gross (Hardy Gross) in the first 25 years of his scientific career, from his study time at the Goethe University in Frankfurt am Main to the time he moved to the Free University of Berlin, as Full Professor. In between there was a fruitful period, in which he worked at the University of California, Santa Barbara, with Walter Kohn, the “father” of Density Functional Theory (DFT). DFT has been the permanent tool of Hardy Gross research. His main achievement in the considered period is the proof of an existence theorem for the Time-Dependent Density Functional (TDDFT) and the search for application schemes in atoms, molecules and solids, starting with linear response. He made notable contributions to the application of DFT and TDDFT to superconductors, in static and dynamic cases.  相似文献   

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Magnetic dipole transitions between the 2Π1/2 and 2Π3/2 components of the ground state of SeH have been observed at about 1780 cm-1 in a L.M.R. experiment using a CO laser. Transitions have been detected for the four most abundant natural isotopes of Se. The transition frequencies depend primarily on the magnitude of the spin-orbit coupling constant and have been analysed in conjunction with data from the E.P.R. spectrum to yield

The admixture of other electronic states by spin-orbit coupling has been investigated to third order in perturbation theory and found to produce significant effects.  相似文献   

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The dynamical system approach is applied to the study of dynamics of multidimensional cosmological models with topology FRW ×T D (D-dimensional torus) in the presence of high-temperature quantum effects. The stability methods developed in the paper of Szydowski (Gen. Rel. Grav.,20, 221, 1988) are used in the analysis of typical states of the metric in the neighborhood of singularities and for large time values. The problems of dynamical dimensional reduction, structure of singularities, isotropization, etc., are discussed in this context.  相似文献   

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