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Lie Symmetries and Conserved Quantities of Holonomic Mechanical Systems in Terms of Quasi-Coordinatee 被引量:1
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作者 傅景礼 刘荣万 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 1998年第3期215-220,共6页
Aim To study the Lie symmetries and conserved quantities of holonomic mechanical systems in terms of qnasi-coordinates. Methods The definition of an infinitesimal generator for the holonomic mechanical systems in te... Aim To study the Lie symmetries and conserved quantities of holonomic mechanical systems in terms of qnasi-coordinates. Methods The definition of an infinitesimal generator for the holonomic mechanical systems in terms of quasi-coordinates was given. Lie's method of the invariance of ordinary differential equations under infinitesimal transformations was used. Results and Conclusion The determining equations of the Lie symmetries of holonomic mechanical systems in terms of quassi-coordinates are established. The structure equation and the form of conserved quantities are obtained. An example to illustrate the applicaiton of the result is given. 展开更多
关键词 analytical mechanics quasi-coordinate Lie symmetry conserved quantity
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Pseudopotential generation
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作者 曹义刚 焦正宽 冯尚申 《Journal of Zhejiang University Science》 EI CSCD 2003年第2期207-213,共7页
Different classes of first-principle pseudopotentials are compared and various schemes for pseudopotential generation based on norm conservation are discussed in this paper. BHS (Bachelet, Hamann, and Schlüter)-... Different classes of first-principle pseudopotentials are compared and various schemes for pseudopotential generation based on norm conservation are discussed in this paper. BHS (Bachelet, Hamann, and Schlüter)-scheme and V (Vanderbilt)-modifications are used to derive the KB (Kleinman and Bylander)-pseudopotentials and pseudo wave functions of bismuth. Quality test of pseudopotentials shows that no ghost states occur in the logarithmic der ivatives of pseudo wave functions of Bismuth. The obtained bond length of bismuth dimer with this type of pseudopotentials is in good agreement with previous accurately calculate d ab initio quantum chemical result. 展开更多
关键词 PSEUDOPOTENTIAL Norm conservation
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Thermodynamic Equilibrium 被引量:1
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作者 Richard Martin Gibbons 《Journal of Energy and Power Engineering》 2016年第10期623-627,共5页
The arguments in this paper lead to a new definition of thermodynamic equilibrium that remedies the deficiencies of the current forms. This definition relates thermodynamic equilibrium to its physical causes and accou... The arguments in this paper lead to a new definition of thermodynamic equilibrium that remedies the deficiencies of the current forms. This definition relates thermodynamic equilibrium to its physical causes and accounts for all factors that determine it for all types of equilibrium. Standard definitions of thermodynamic equilibrium are incomplete. They do not take account of all factors that determine such equilibriums, discuss the impediments which may prevent them being reached or relate the properties that define equilibriums to the physical reasons that determine them when impediments are present. The laws of thermodynamics determine the requirements for equilibrium. These laws arise from the physical behaviour of the molecules in molecular systems and are consequences of the conservation of energy, the energies of molecules, statistics, Newton's laws of motion, and the equi-partition of energy. The standard definition of thermodynamic equilibrium correctly defines equilibrium whenever impediments are not factors. The discussion demonstrates how impediments arise, accounts for their role in defining equilibrium and how they relate to the energies of molecules at the conditions of the system. The new definition applies to all types of equilibrium. 展开更多
关键词 THERMODYNAMICS EQUILIBRIUM statistical mechanics.
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Constraints on the R-Parity Violating Couplings Using the Newest Measurement of the Decay B08 →μ+μ-
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作者 LI Cheng Lü Cai-Dian GAO Xiang-Dong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第6期711-713,共3页
Recently, the LHCb collaboration reported the first evidence for the decay B08 →μ+μ-. A branching ratio of (B08 →μ+μ-) = (3.2+1.5-1.2) x 10-9 is given. Using the newest data, and together with the most pr... Recently, the LHCb collaboration reported the first evidence for the decay B08 →μ+μ-. A branching ratio of (B08 →μ+μ-) = (3.2+1.5-1.2) x 10-9 is given. Using the newest data, and together with the most precise predictions of the Standard Model contributions to the decay, we derive the constraints on the combinations of the R-parity violating parameters. Our results are several orders of magnitudes stronger than the constraints in the previous literature. We also update the constraints on the relevant parameters using the upper limit of B(B08 →μ+μ-). 展开更多
关键词 SUPERSYMMETRY rare decay R-PARITY
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