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NOETHER’S CONSERVATION LAWS OF HOLONOMIC NONCONSERVATIVE DYNAMICAL SYSTEMS IN GENERALIZED MECHANICS 被引量:2
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作者 乔永芬 岳庆文 董永安 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第9期877-883,共7页
In the present paper, three kinds of forms for Noether’s conservation laws of hol-onomic nonconservative dynamical systems in generalized mechanics are given.
关键词 generalized mechanics Hamilton canonical equation Raitzincanonical equation Noether’s conservation law
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Principles of Quantum Mechanics and Laws of Wave Optics from One Mathematical Formula
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作者 Do Tan Si 《Applied Mathematics》 2019年第11期892-906,共15页
Finding that in the formula of expansion of a function into a series of wave-like functions ?the coefficients are its Fourier transforms, if existed, we deduce mathematically all the principles and hypothesis that ill... Finding that in the formula of expansion of a function into a series of wave-like functions ?the coefficients are its Fourier transforms, if existed, we deduce mathematically all the principles and hypothesis that illustrated physicists utilized to build quantum mechanics a century ago, beginning with the duality particle-wave principle of Planck and including the Schr&ouml;dinger equations. By the way, we find a simple Fourier transform relation between Dirac momentum and position bras and a useful permutation relation between operators in phase and Hilbert spaces. Moreover, from the found particle-wave duality formula we prove and obtain again essentially by mathematical analysis all the laws of wave optics concerning reflections, refractions, polarizations, diffractions by one or many identical 3D objects with various forms and dimensions. 展开更多
关键词 FOURIER Transform in Quantum mechanics PERMUTATION Relations between OPERATORS laws of Wave Optics Diffractions by Multiform Identical Objects
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Contradiction between Conservation Laws and Orthodox Quantum Mechanics
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作者 M. E. Burgos 《Journal of Modern Physics》 2010年第2期137-142,共6页
In this paper, it showed that the orthodox version of quantum mechanics contradicts the idea that conservation laws are valid in individual processes of measurement.
关键词 CONSERVATION laws ORTHODOX Quantum mechanics Measuring Problem
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Primary Assumptions and Guidance Laws in Wave Mechanics
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作者 Adriano Orefice Raffaele Giovanelli Domenico Ditto 《Journal of Applied Mathematics and Physics》 2018年第12期2621-2634,共14页
In an article written by Louis de Broglie in 1959 (30 years after the Nobel prize rewarding his foundation of Wave Mechanics), the most challenging problem raised by the Bohr, Heisenberg and Born Standard Quantum Mech... In an article written by Louis de Broglie in 1959 (30 years after the Nobel prize rewarding his foundation of Wave Mechanics), the most challenging problem raised by the Bohr, Heisenberg and Born Standard Quantum Mechanics (SQM) was pointed out in the renunciation to describe “a permanent localization in space, and therefore a well-defined trajectory” for any moving particle. This challenge is taken up in the present paper, showing that de Broglie’s Primary Assumption p=hk, predicting the wave-particle duality, does also allow to obtain from the energy-dependent form of the Schr&#246;dinger and/or Klein-Gordon equations the Guidance Laws piloting particles along well-defined trajectories. The energy-independent equations, on the other hand, may only give rise—both in SQM and in the Bohmian approach—to probabilistic descriptions, overshadowing the role of de Broglie’s matter waves in physical space. 展开更多
关键词 Helmholtz Equation Wave Potential Hamilton-Jacobi Equations Wave mechanics de Broglie’s Duality Matter Waves Guidance laws Schrodinger Equations Klein-Gordon Equations
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No country is an island in regulating food safety:How the WTO monitors Chinese food safety laws through the Trade Policy Review Mechanism(TPRM) 被引量:4
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作者 Francis Snyder 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第11期2142-2156,共15页
Established within the framework of the World Trade Organization (WTO), the Trade Policy Review Mechanism (TPRM) reviews periodically the trade policies of all WTO Members. The review includes many aspects of food... Established within the framework of the World Trade Organization (WTO), the Trade Policy Review Mechanism (TPRM) reviews periodically the trade policies of all WTO Members. The review includes many aspects of food safety regulation. China's trade policy is reviewed every two years. This paper analyses in detail the reviews of China's trade policy in 2006, 2008, 2010, 2012 and 2014. It focuses in particular on food safety laws and types of standards, alignment of domestic standards with international standards, the role of different domestic institutions, transparency and notification of food safety measures under the WTO agreements on Sanitary and Phytosanitary Measures (SPS) and on Technical Barriers to Trade (TBTAgreement), import and export, and geographical indications (GIs). It concludes that the WTO TPRM can contribute, within its mandate, to reform of Chinese food safety laws and improvement of food safety in China. it notes that China has already undertaken substantial reforms of its system for regulating food safety. It recommends that China should continue to participate actively in the TPRM, follow its own path with regard to alignment and learn selectively from other WTO Members. 展开更多
关键词 food safety food standards public health consumer welfare China Chinese food safety laws World Trade Organization WTO law Trade Policy Review mechanism (TPRM) SPS Agreement TBT Agreement
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Integrating Factors and Conservation Laws for Relativistic Mechanical System 被引量:4
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作者 ZHANG Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2X期231-234,共4页
In this paper, we present a new method to construct the conservation laws for relativistic mechanical systems by finding corresponding integrating factors. First, the Lagrange equations of relativistic mechanical syst... In this paper, we present a new method to construct the conservation laws for relativistic mechanical systems by finding corresponding integrating factors. First, the Lagrange equations of relativistic mechanical systems are established, and the definition of integrating factors of the systems is given; second, the necessary conditions for the existence of conserved quantities of the relativistic mechanical systems are studied in detail, and the relation between the conservation laws and the integrating factors of the systems is obtained and the generalized Killing equations for the determination of the integrating factors are given; finally, the conservation theorem and its inverse for the systems are established, and an example is given to illustrate the application of the results. 展开更多
关键词 RELATIVITY mechanical system conservation law integrating factor Killing equation
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Mechanical Properties of Simple s-p Metals, and Defect Energies from Electron Theory and from Interatomic Force Laws 被引量:1
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作者 N.H.March(Oxford University, Oxford, U.K.) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1997年第2期81-85,共5页
The cleavage force F(z) needed to separate parallel atomic planes by a distance z is first discussed for simple s-p metals using density functional theory.For the s-p nearly free-electron metals the linearized Thomas-... The cleavage force F(z) needed to separate parallel atomic planes by a distance z is first discussed for simple s-p metals using density functional theory.For the s-p nearly free-electron metals the linearized Thomas-Fermi equation is solved self-consistently in the cases of (a) semi-infinite planes of jellium (i.e. smeared uniform positive ions) and (b) a semi-infinite cylinder of finite radius, cleaved by a plane perpendicular to its axis. In (a), the elastic region has the form F(z)=Az ∝ Zrs-11/2, where rs is the mean interelectronic distance in the jellium model. Size effects are then considered, with possible relevance to atomic force microscopy.Defect energies are treated, using both electron theory and pair force laws. 展开更多
关键词 and Defect Energies from Electron Theory and from Interatomic Force laws mechanical Properties of Simple s-p Metals Rev
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Derivation of Maxwell’s Equations via the Covariance Requirements of the Special Theory of Relativity, Starting with Newton’s Laws
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作者 Allan D. Pierce 《Journal of Applied Mathematics and Physics》 2019年第9期2052-2073,共22页
The purpose of this paper is to establish a connection between Maxwell’s equations, Newton’s laws, and the special theory of relativity. This is done with a derivation that begins with Newton’s verbal enunciation o... The purpose of this paper is to establish a connection between Maxwell’s equations, Newton’s laws, and the special theory of relativity. This is done with a derivation that begins with Newton’s verbal enunciation of his first two laws. Derived equations are required to be covariant, and a simplicity criterion requires that the four-vector force on a charged particle be linearly related to the four-vector velocity. The connecting tensor has derivable symmetry properties and contains the electric and magnetic field vectors. The Lorentz force law emerges, and Maxwell’s equations for free space emerge with the assumption that the tensor and its dual must both satisfy first-order partial differential equations. The inhomogeneous extension yields a charge density and a current density as being the source of the field, and yields the law of conservation of charge. Newton’s third law is reinterpreted as a reciprocity statement, which requires that the charge in the source term can be taken as the same physical entity as that of the test particle and that both can be assigned the same units. Requiring covariance under either spatial inversions or time reversals precludes magnetic charge being a source of electromagnetic fields that exert forces on electric charges. 展开更多
关键词 RELATIVITY Maxwell’s EQUATIONS newton’s laws COVARIANCE
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Coordination Mechanism of the Legal Protection of Resource Security with Its Relative Laws
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作者 Chen Demin Wang Huabing 《Chinese Journal of Population,Resources and Environment》 北大核心 2008年第3期21-26,共6页
The basis of the legal protection of resource security is its relative laws, which have four main characteristics, which are foundational, divergent, comprehensive and of long-term social benefits in view. The coordin... The basis of the legal protection of resource security is its relative laws, which have four main characteristics, which are foundational, divergent, comprehensive and of long-term social benefits in view. The coordination mechanism of the legal protection of resource security with its relative laws meets the needs of the sustainable development of the economy, society and environment. It also facilitates and is facilitated by the modern transformation of the legal system in China, and upholds the legal system as a logically self-perfecting entity. Furthermore, this coordination bears scientific feasibility. 展开更多
关键词 resource security legal protection relative laws mechanISM
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Study on the Geohazard Distribution Laws and Hazard-Causing Mechanism in Menghai County of Yunnan Province
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作者 Mingchang Hei Xuegang Dai +2 位作者 Xukai Yuan Jia Xiong Xiaobo Kang 《Journal of World Architecture》 2021年第5期14-21,共8页
The study area is located at the southwest border of Yunnan Province and the southward extended part of Nushan Mountain,with complex and fragile geo-environmental conditions.Deep geological survey and mathematical ana... The study area is located at the southwest border of Yunnan Province and the southward extended part of Nushan Mountain,with complex and fragile geo-environmental conditions.Deep geological survey and mathematical analytical investigation on the geohazard distribution and hazard-causing mechanisms in this area were carried out in this study.The results revealed that:(1)The development of geohazards was affected differently by difierent slope shapes,slope structures and elevations;(2)Most of the geohazards were developed in medium shallow cut ridge-like medium-height mountainous geomorphological region and shallow cut steamed bun-like low and medium-height mountainous geomorphological region,and they were relatively concentrated on tectonic zones like fault zones;(3)The slopes formed by loose earth piling up on the surface of Indo-Chinese magmatic rock and Lancang Group metamorphic rock formations were most prone to slope instability and even landslide.The deep study on the geohazard distribution and hazard-causing mechanisms can provide geoscientific basis and reference for the prevention and mitigation work of geohazards under similar geo-environmental conditions. 展开更多
关键词 Menghai County GEOHAZARD Distribution law Hazard-causing mechanism
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Studies on the Evolutionary Laws and Maintaining Mechanism of Renewability of the Yellow River's Water Resources
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《Bulletin of the Chinese Academy of Sciences》 2002年第4期204-206,共3页
  The Yellow River has a vast catchment area and historically it is the mother river of the Chinese nation. Now it serves as one of the main theatres for the on-going national campaign to develop China's western...   The Yellow River has a vast catchment area and historically it is the mother river of the Chinese nation. Now it serves as one of the main theatres for the on-going national campaign to develop China's western hinterland.…… 展开更多
关键词 Studies on the Evolutionary laws and Maintaining mechanism of Renewability of the Yellow River’s Water Resources laws
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CONSERVATION LAWS AND SYMMETRIES OF SYSTEMS WITH UNILATERAL CONSTRAINTS IN PHASE SPACE 被引量:2
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作者 Zhang Yi Mei Fengxiang 《Acta Mechanica Solida Sinica》 SCIE EI 1999年第1期22-30,共9页
By introducing the generalized quasi-symmetry of the infinitesimaltransformation for transformation group G_r, this paper studies theconservation laws and symmetries of dynamical systems with unilateralconstraints in ... By introducing the generalized quasi-symmetry of the infinitesimaltransformation for transformation group G_r, this paper studies theconservation laws and symmetries of dynamical systems with unilateralconstraints in phase space. Noether's theorem and Noether's inversetheorem for me- chanical system with unilateral constraints in phasespace are obtained and two kinds of equivalent forms of generalizedKilling equations which are used to determine the generators of theinfinitesimal group transformation are given. 展开更多
关键词 analytical mechanics conservation law SYMMETRY
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STUDIES ON MECHANICS PROBLEM OF DYNAMIC WALKING OF ANTHROPOMORPHIC BIPED ROBOTS 被引量:1
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作者 Tan Guanzheng Yang Hongzhi(Robottes Research Centre, Central South University of Technology, Changsha, 410083, China) 《Journal of Central South University》 SCIE EI CAS 1995年第2期59-65,共7页
This paper deals with the mechanics problem of dynamic walking of anthropomorphic biped robots. Through analysing the mechanics system of this kind of robots in detail, the motion constraint equations are established,... This paper deals with the mechanics problem of dynamic walking of anthropomorphic biped robots. Through analysing the mechanics system of this kind of robots in detail, the motion constraint equations are established, three mechanics laws describing the r 展开更多
关键词 anthropomorphic BIPED robot DYNAMIC WALKING mechanics system mechanics laws measuring and computing
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The Research of the Flow of Bodies with Use of the Vector Form of the Newton’s Law for the Viscous Liquid 被引量:2
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作者 Andrey N. Volobuev Eugene S. Petrov 《Engineering(科研)》 2011年第2期162-167,共6页
On the basis of the vector formula of the Newton’s law for a viscous liquid and the integrated vector form of the equation of an impulse for a viscous liquid for resistance and carrying power of a profile of any form... On the basis of the vector formula of the Newton’s law for a viscous liquid and the integrated vector form of the equation of an impulse for a viscous liquid for resistance and carrying power of a profile of any form and the big length dependences are found in a stream. Application of the found dependences at a circulating flow of the cylinder located across a stream is showed. The analysis of a tensor of viscosity for laminar and turbulent flow is carried out. 展开更多
关键词 newton’s law for VISCOSITY A Body FLOW CIRCULATION of Speed Resistance Factor A VISCOSITY TENSOR
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Formation Mechanism and Occurrence Law of Pod Shattering in Soybean:A Review 被引量:1
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作者 Jinfeng Liu Yuzhe Zhang +6 位作者 Yushi Jiang Hongji Sun Ruijie Duan Jing Qu Dan Yao Siyan Liu Shuyan Guan 《Phyton-International Journal of Experimental Botany》 SCIE 2022年第7期1327-1340,共14页
Seed shattering refers to the phenomenon in which the pods split along the abdominal and back sutures before the crop is received,so that the seeds are spread.Seed shattering is vital to the reproduction of their offs... Seed shattering refers to the phenomenon in which the pods split along the abdominal and back sutures before the crop is received,so that the seeds are spread.Seed shattering is vital to the reproduction of their offspring in wild plants,but it is also the main cause of crop yield loss reason.Pod-explosion resistance is a complex process of physical and physiological and biochemical reactions.Soybean seed shattering phenomenon is widespread,which severely restricts the development of soybean industry.Seed shattering(pod cracking or fruit dropping)is essential for the reproduction of its offspring in wild plants,but it is also the main cause of crop yield loss.This article analyzes the morphology and structure of pods related to seed shattering from the morphology of pods.On the basis of the regularity of the occurrence of seed shattering and the summary of phenotypic index identification methods,physiologically introduced the regulation mechanism of key enzymes and endogenous hormones on seed shattering.The localization,labeling and cloning of seed shattering genes are introduced in molecular biology.The study focused on reviewing the latest advances in the research on soybean seed shattering characteristics,and discussed with the research results of related crops.Finally,the research and application of soybean seed shattering resistance were prospected for several aspects. 展开更多
关键词 Seed shattering genetic law identification mechanism of action
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Q-Theory: A Connection between Newton’s Law and Coulomb’s Law? 被引量:1
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作者 Christopher Pilot 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第2期632-660,共29页
Assuming a Winterberg model for space where the vacuum consists of a very stiff two-component superfluid made up of positive and negative mass planckions, Q theory is the hypothesis, that Planck charge, <i>q<... Assuming a Winterberg model for space where the vacuum consists of a very stiff two-component superfluid made up of positive and negative mass planckions, Q theory is the hypothesis, that Planck charge, <i>q<sub>pl</sub></i>, was created at the same time as Planck mass. Moreover, the repulsive force that like-mass planckions experience is, in reality, due to the electrostatic force of repulsion between like charges. These forces also give rise to what appears to be a gravitational force of attraction between two like planckions, but this is an illusion. In reality, gravity is electrostatic in origin if our model is correct. We determine the spring constant associated with planckion masses, and find that, <img src="Edit_770c2a48-039c-4cc9-8f66-406c0cfc565c.png" width="90" height="15" alt="" />, where <i>ζ</i>(3) equals Apery’s constant, 1.202 …, and, <i>n</i><sub>+</sub>(0)=<i>n</i>_(0), is the relaxed, <i>i.e.</i>, <img src="Edit_813d5a6f-b79a-49ba-bdf7-5042541b58a0.png" width="25" height="12" alt="" />, number density of the positive and negative mass planckions. In the present epoch, we estimate that, <i>n</i><sub>+</sub>(0) equals, 7.848E54 m<sup>-3</sup>, and the relaxed distance of separation between nearest neighbor positive, or negative, planckion pairs is, <i>l</i><sub>+</sub>(0)=<i>l</i><sub>_</sub>(0)=5.032E-19 meters. These values were determined using box quantization for the positive and negative mass planckions, and considering transitions between energy states, much like as in the hydrogen atom. For the cosmos as a whole, given a net smeared macroscopic gravitational field of, <img src="Edit_efc8003d-5297-4345-adac-4ac95536934d.png" width="80" height="15" alt="" />, due to all the ordinary, and bound, matter contained within the observable universe, an average displacement from equilibrium for the planckion masses is a mere 7.566E-48 meters, within the vacuum made up of these particles. On the surface of the earth, where, <i>g</i>=9.81m/s<sup>2</sup>, the displacement amounts to, 7.824E-38 meters. All of these displacements are due to increased gravitational pressure within the vacuum, which in turn is caused by applied gravitational fields. The gravitational potential is also derived and directly related to gravitational pressure. 展开更多
关键词 Extended Gravity Winterberg Model Planckion Mass Theory Modified Quantum Vacuum Planck Charge newton’s law Coulomb’s law Dark Energy
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Formally Deriving the Third Newton’s Law from a Pair of Nontrivial Assumptions in a Formal Axiomatic Theory “Sigma-V” 被引量:1
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作者 Vladimir O. Lobovikov 《Journal of Applied Mathematics and Physics》 2022年第5期1561-1586,共26页
The article is devoted to hitherto never undertaken applying an almost unknown logically formalized axiomatic epistemology-and-axiology system called “Sigma-V” to the Third Newton’s Law of mechanics. The author has... The article is devoted to hitherto never undertaken applying an almost unknown logically formalized axiomatic epistemology-and-axiology system called “Sigma-V” to the Third Newton’s Law of mechanics. The author has continued investigating the extraordinary (paradigm-breaking) hypothesis of formal-axiological interpreting Newton’s mathematical principles of natural philosophy and, thus, has arrived to discrete mathematical modeling a system of formal axiology of nature by extracting and systematical studying its proper algebraic aspect. Along with the proper algebraic machinery, the axiomatic (hypothetic-deductive) method is exploited in this investigation systematically. The research results are the followings. 1) The Third Newton’s Law of mechanics has been modeled by a formal-axiological equation of two-valued algebraic system of metaphysics as formal axiology. (Precise defining the algebraic system is provided.) The formal-axiological equation has been established (and examined) in this algebraic system by accurate computing compositions of relevant evaluation-functions. Precise tabular definitions of the evaluation-functions are given. 2) The wonderful formula representing the Third Newton’s Law (in the relevant physical interpretation of the formal theory Sigma-V) has been derived logically in Sigma-V from the presumption of a-priori-ness of knowledge. A precise axiomatic definition of the nontrivial notion “a-priori-ness of knowledge” is given. The formal derivation is implemented in strict accordance with the rigor standard of D. Hilbert’s formalism;hence, checking the formal derivation submitted in this article is not a difficult task. With respect to proper theoretical physics, the formal inference is a nontrivial scientific novelty which has not been discussed and published elsewhere yet. 展开更多
关键词 Third law of newton’s mechanics Logically Formalized Axiomatic Theory Σ-V Two Valued Algebraic System of Metaphysics as Formal Axiology A-Priori Knowledge Formal Derivation from Assumption
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Damage Mechanics of Ferrite Ductile Iron under Uniaxial Stress
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作者 LIUJin-hai LIGuo-lu +2 位作者 FUHan-guang HAOXiao-yan LIUGen-sheng 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2003年第3期41-45,共5页
According to the principle of damage mechanics,the damage characteristics of ferrite nodular cast iron under uniaxial stress were studied by measuring electric resistance. The results show that the damage in nodular c... According to the principle of damage mechanics,the damage characteristics of ferrite nodular cast iron under uniaxial stress were studied by measuring electric resistance. The results show that the damage in nodular cast iron occurs when the applied stress is more than a certain extent,and the damage variable increases with stress. The evolutional law of damage variable as a function of stress was obtained.The damage threshold of nodular cast iron increases with nodularity,but it is below the yield strength,which provides reference significance to the design of machinery structure and the choice of materials.The critical damage variable is not related to the nodularity,which is about 0. 060-0. 068. 展开更多
关键词 nodular cast iron damage mechanics evolutional law damage threshold critical damage variable
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THE THEORY OF RELATIVISTIC ANALYTICAL MECHANICS OF THE ROTATIONAL SYSTEMS
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作者 罗绍凯 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1998年第1期45-57,共13页
The theory of rotational relativistic mechanics is discussed and the theory of relativistic analytical mechanics' of the rotational systems is constructed. The relativistic generalized kinetic energy function for ... The theory of rotational relativistic mechanics is discussed and the theory of relativistic analytical mechanics' of the rotational systems is constructed. The relativistic generalized kinetic energy function for the rotational systems [GRAPHICS] and the generalized acceleration energy function [GRAPHICS] are constructed, and furthermore, the Hamilton principle and three kinds of D'Alembert principles are given. For the systems with holonomic constraints, the relativistic Lagrange equation, Nielsen equation, Appell equation and Hamilton canonical equation of the rotational systems are constructed; For the systems with nonholonomic constraints, the relativistic Routh equation, Chaplygin equation, Nielsen equation and Appell equation of the rotational systems are constructed; the relativistic Noether conservation law of the rotational systems are given too. 展开更多
关键词 rotational systems RELATIVITY analytical mechanics nonholonomic constraints variation principle equation of motion conservation law
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Deformation and Densification Laws of Powder Cold Forging
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作者 余世浩 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2007年第1期17-21,共5页
The deformation and densification laws of preform upsetting and closed-die forging were researched based on experimental results of cold forging of deoxidized Fe powder sintering porous material under different initia... The deformation and densification laws of preform upsetting and closed-die forging were researched based on experimental results of cold forging of deoxidized Fe powder sintering porous material under different initial conditions such as friction factor, ratio between height and diameter and relative density. The fracture limit criteria" for powder cold-forging upsetting and the limit strain curve were achieved. The effect of friction facto,, ratlt, between height and diameter and relative density on fracture strain limitation was emphatically analyzed. The limit process parameter curves for the deformation of upsetting were also confirmed. Laws of deformation, densification and density distribution for closed-die forging of powder perform during cold-forging were further analyzed and discussed with the help of experimental phase analysis. As a result, this experiment established theoretical foundations for the design of preform and die as well as optimization of technological process parameters. 展开更多
关键词 powder cold-forging fracture limit strain criterion deformation law densification mechanism
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