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惯性激振器激振力指示牌分度原理 被引量:1
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作者 韩京燕 韩成年 《中国铸造装备与技术》 CAS 2000年第3期44-46,共3页
通过数学推导 ,得出了最大激振力百分数与偏心块重合的关系式 ,此式可准确。
关键词 惯性激振器 激振力指示牌 分度原理
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速比分度原理在工具专用机床上的应用
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作者 董利 张庆春 《林业机械与木工设备》 1996年第6期25-26,共2页
速比分度原理在工具专用机床上的应用(161005)齐齐哈尔第二机床厂董利(150030)哈尔滨阀门厂张庆春X8514型自动立铣刀槽铣床可用于加工φ6~14mm直柄粗齿立铣刀沟槽,其齿数Z=3,螺旋角右旋,全部动作均实... 速比分度原理在工具专用机床上的应用(161005)齐齐哈尔第二机床厂董利(150030)哈尔滨阀门厂张庆春X8514型自动立铣刀槽铣床可用于加工φ6~14mm直柄粗齿立铣刀沟槽,其齿数Z=3,螺旋角右旋,全部动作均实现自动化.下面,我们将分析在设计中... 展开更多
关键词 机床 速比分度原理 应用
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车床滑板圆周滚压刻线的研究
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作者 谭德宁 《新技术新工艺》 2008年第10期27-29,共3页
介绍了圆周滚度装置的设计原理和结构,阐述了如何设计和制作的方法。并通过实例分析和结构对比,说明了不同场合应该选用什么样的结构。证明研究的圆周刻度装置具有一定的应用前景。
关键词 滚动分度原理 滚动分度结构 实例分析
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干燥过滤器器体批量生产的工艺设计
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作者 徐贵勇 《模具制造》 2009年第7期31-37,共7页
干燥过滤器器体的生产一直以来都是制约国内干燥过滤器生产的瓶颈,通过对器体的工艺分析,结合国内外工艺设计情况,利用高速回转分度原理,重新对该器体的成形工艺进行了设计,满足了批量生产的技术质量要求,大大提高了生产效率。同时,为... 干燥过滤器器体的生产一直以来都是制约国内干燥过滤器生产的瓶颈,通过对器体的工艺分析,结合国内外工艺设计情况,利用高速回转分度原理,重新对该器体的成形工艺进行了设计,满足了批量生产的技术质量要求,大大提高了生产效率。同时,为同类产品的批量生产提供了借鉴。 展开更多
关键词 干燥过滤器器体 工艺设计 高速回转 分度原理 模具结构
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Determination of thermodynamic properties in full composition range of Ti-Al binary melts based on atom and molecule coexistence theory 被引量:1
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作者 Sheng-chao DUAN Xiao SHI +2 位作者 Wen-sheng YANG Han-jie GUO Jing GUO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第6期1256-1264,共9页
The results of predicting thermodynamic properties in the full composition range of Ti-Al binary melts in a temperature range from 1973 to 2273 K were obtained by coupling with the developed thermodynamic model for ca... The results of predicting thermodynamic properties in the full composition range of Ti-Al binary melts in a temperature range from 1973 to 2273 K were obtained by coupling with the developed thermodynamic model for calculating mass action concentration N_i of structural units in Ti-Al system based on the atom and molecule coexistence theory(AMCT). Temperature dependence of the activity coefficients of Ti and Al in natural logarithmic form in the infinitely dilute solution(0x_(Ti)0.01) of Ti-Al binary melts was also determined from the calculated activity coefficients of Ti and Al at temperatures of 1973, 2073, 2173, and 2273 K. The standard molar Gibbs free energy change of dissolving pure liquid element i(l) for forming 1%(mass fraction) element i in Ti-Al binary melts further was deduced. With the aid of this model, meanwhile, the determined excess thermodynamic properties, such as the excess molar mixing Gibbs free energy/entropy/enthalpy were also calculated. 展开更多
关键词 Ti-Al binary system Ti Al activity coefficient thermodynamic model mass action concentration atom and molecule coexistence theory
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利用误差均分法加工大型离合器
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作者 李淑彦 《一重技术》 1990年第2期15-20,共6页
文章分析了以往用于加工大型离合器的样板法工艺所存在的问题及其加工误差问题,论述了圆分度封闭原理,据之提出了加工离合器齿面的新方法——误差均分法,并举实例说明该法不使用样板,可满足较高精度的加工要求,是一种有推广价值的... 文章分析了以往用于加工大型离合器的样板法工艺所存在的问题及其加工误差问题,论述了圆分度封闭原理,据之提出了加工离合器齿面的新方法——误差均分法,并举实例说明该法不使用样板,可满足较高精度的加工要求,是一种有推广价值的工艺方法。 展开更多
关键词 离合器 误差均分法 样板法 分度封闭原理 齿轮加工
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Fuzzy Ontology Construction Based on Incomplete Knowledge
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作者 Liu Jie Li Dongle +1 位作者 Zhang Yuan Luo Liming 《China Communications》 SCIE CSCD 2012年第11期78-86,共9页
There exists widely incomplete knowledge all over the world, but incomplete knowledge still cannot be dealt with in the process of ontology construction. Hence, a method for fuzzy ontology construction based on incomp... There exists widely incomplete knowledge all over the world, but incomplete knowledge still cannot be dealt with in the process of ontology construction. Hence, a method for fuzzy ontology construction based on incomplete knowledge is proposed. First, the calculation principle of the attribute weight of the ontology concept is presented, and the calculation function of the attribute weight is derived through experiments. Then, the membership degree of the incomplete individual to the concept is computed. Finally, the incomplete individual is classified according to the principle of the variable precision rough set model. The experimental results show that the average precision of the classification of the incomplete individuals is 81.7% when the common attributes are omitted and that it is difficult to classify the incomplete individuals correctly when the private attributes are omitted. This method is significant for handling incomplete knowledge in the process of ontology construction. 展开更多
关键词 ontology construction fuzzy ontology uncertain knowledge incomplete knowledge
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Numerically Simulating the Sandwich Plate System Structures
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作者 冯国庆 李刚 +2 位作者 刘志慧 牛怀磊 李陈峰 《Journal of Marine Science and Application》 2010年第3期286-291,共6页
Sandwich plate systems (SPS) are advanced materials that have begun to receive extensive attention in naval architecture and ocean engineering.At present, according to the rules of classification societies, a mixture ... Sandwich plate systems (SPS) are advanced materials that have begun to receive extensive attention in naval architecture and ocean engineering.At present, according to the rules of classification societies, a mixture of shell and solid elements are required to simulate an SPS.Based on the principle of stiffness decomposition, a new numerical simulation method for shell elements was proposed.In accordance with the principle of stiffness decomposition, the total stiffness can be decomposed into the bending stiffness and shear stiffness.Displacement and stress response related to bending stiffness was calculated with the laminated shell element.Displacement and stress response due to shear was calculated by use of a computational code write by FORTRAN language.Then the total displacement and stress response for the SPS was obtained by adding together these two parts of total displacement and stress.Finally, a rectangular SPS plate and a double-bottom structure were used for a simulation.The results show that the deflection simulated by the elements proposed in the paper is larger than the same simulated by solid elements and the analytical solution according to Hoff theory and approximate to the same simulated by the mixture of shell-solid elements, and the stress simulated by the elements proposed in the paper is approximate to the other simulating methods.So compared with calculations based on a mixture of shell and solid elements, the numerical simulation method given in the paper is more efficient and easier to do. 展开更多
关键词 sandwich plate system (SPS) stiffness decomposition laminated shell element
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Effect of Stretching - Setting Treatment on Dyeing Behavior of Wool
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作者 林琳 《Journal of Donghua University(English Edition)》 EI CAS 2003年第4期12-16,共5页
Changes of dyeing behavior of wool after stretching - setting treatment are studied.Effects of stretching - setting on wool structure are analyzed.It is concluded that stretching - setting treatment not only reduces w... Changes of dyeing behavior of wool after stretching - setting treatment are studied.Effects of stretching - setting on wool structure are analyzed.It is concluded that stretching - setting treatment not only reduces wool diameter and increases wool length,but also brings about low-temperature dyeing of wool. 展开更多
关键词 WOOL STRETCHING stretching - setting dyeing behavior law-temperature dyeing
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First-principles study of lithium intercalated bilayer graphene 被引量:4
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作者 ZHOU JingJing ZHOU WeiWei +5 位作者 GUAN ChunMei SHEN JingQin OUYANG ChuYing LEI MinSheng SHI SiQi TANG WeiHua 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第8期1376-1382,共7页
Litbium intercalated bilayer graphene has been investigated using first-principles density functional theory calculations. Re- sults show that there exist AB and AA stacking sequences for bilayer graphene in which the... Litbium intercalated bilayer graphene has been investigated using first-principles density functional theory calculations. Re- sults show that there exist AB and AA stacking sequences for bilayer graphene in which the latter is more favorable for the Li storage and the former will evolve into the latter with the intercalation of Li ions. The relationship between the interlayer dis- tance of two graphene sheets and the intercalated capacity of Li ions is discussed, It is found that structural defect is identified to store Li ions more favorably than pristine bilayer graphene and an isolated C atom vacancy in bilayer graphene can capture three Li ions between two graphene sheets. 展开更多
关键词 bilayer grapheme lithium ion battery DEFECT first-principles calculation
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Flow field optimization and design for a Spallation Neutron Source target cooling system 被引量:1
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作者 HAO JunHong CHEN Qun +2 位作者 XU YunChao LU YouLian JI Quan 《Science China(Technological Sciences)》 SCIE EI CAS 2013年第6期1370-1376,共7页
Cooling water is an important part in a Spallation Neutron Source target cooling system, but the unstable vortexes at the exits of the slits between every two tungsten target slices have a negative impact on the stabl... Cooling water is an important part in a Spallation Neutron Source target cooling system, but the unstable vortexes at the exits of the slits between every two tungsten target slices have a negative impact on the stable running of the target system. We apply the field synergy principle for fluid flow to obtain the optimal flow field, which has a uniform velocity distribution without eddy, and then, optimize the geometrical structure of the cooling water flow channel based on the optimal flow field. The results show that when the cooling water flows in the optimized channel, the eddy sizes decrease, the time fluctuations of velocity and pressure almost vanish, and the volume flow rates of the cooling water in each parallel slit are uniform. Therefore, it effectively improves the running stability of the target system with the premise of satisfying the target heat load. 展开更多
关键词 spallation neutron source target cooling system flow channel design field synergy equation
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Calculation of Excited States of He Atoms in a Strong Magnetic Field
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作者 赵力波 B.C.Saha 杜孟利 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第6期1059-1065,共7页
A recently developed B-spline algorithm is extended and utilized to calculate excited states of He atoms in the presence of strong magnetic fields.Binding energies are presented for He in the five excited atomic state... A recently developed B-spline algorithm is extended and utilized to calculate excited states of He atoms in the presence of strong magnetic fields.Binding energies are presented for He in the five excited atomic states 210-+,110-,210-,11(-1)+,and 2 1(1) + with magnetic field strength ranging from 0.0001 to 10 a.u.The obtained energies are compared with available theoretical data,and found to be in good agreement.We investigate influence of magnetic fields on atomic structures of multielectron atoms,and illustrate that how electron probability density distributions change with increasing magnetic field strength.The current approach is directly applicable to simulations of discrete spectra for He atoms in the atmospheres of magnetized white dwarf stars. 展开更多
关键词 He atom magnetic field B-spline basis
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First-principles investigation of the effects of B impurities on the mechanical properties of NiAl intermetallics 被引量:4
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作者 HU XueLan LIU Xu +2 位作者 XU Zhou LIANG JiaChang WANG TianMin 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第5期809-814,共6页
We have investigated the effects of B impurities on the structure and mechanical properties of NiA1 intermetallics by using a first-principles pseudopotential total-energy method, based on the density functional theor... We have investigated the effects of B impurities on the structure and mechanical properties of NiA1 intermetallics by using a first-principles pseudopotential total-energy method, based on the density functional theory with a generalized gradient approximation. We found that the impurity B atoms can either replace Ni atoms or Al atoms or both, depending on the surround- ing environment. We demonstrated that the presence of B will cause an increase in brittleness and a decrease in the ductility of NiAI for the Al-substitutional case, while causing an increase in the ductility of NiAl for the Ni-subtitutional case, based on the calculated elastic constants and the empirical criterions. This indicates that the effects of B impurities on the mechanical prop- erties of NiAl intermetallics are quite composition-dependent. 展开更多
关键词 NiAl intermetallics B impurity MECHANICAL FIRST-PRINCIPLES
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Structural and Interaction Properties of Porphyrin Layers — A Quantum Chemical Study
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作者 G.Praveena A.Abiram 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第5期625-634,共10页
This paper is proposed to understand the interaction of porphyrin layers with diatomic molecules interacting at their interior regions by applying ab initio and density functional theory (DFT) methods. We have used ... This paper is proposed to understand the interaction of porphyrin layers with diatomic molecules interacting at their interior regions by applying ab initio and density functional theory (DFT) methods. We have used NO, GO, and O2 diatomic molecules to interact with the porphyrin layers. The most common Fe-centered metalloporphyrin structure with tetra-pyrrlic rings having N4 core is chosen for the study. The optimization of Porphyrin-Porphyrin (PI-PII) and Porphyrin-Diatomic molecule-Porphyrin (P1-AB-P11) (AB = NO, CO, and 02) complexes are performed using HF method. In order to understand the planarity and appropriate stacking size of porphyrins and also to infer the separation of diatomic molecules between porphyrin layers the behavior of PI-AB-PH complexes (where AB = NO, CO, and 02) are analyzed using structural properties and molecular electrostatic potentials (MEP). The MEPs are caiculated using hybrid exchange correlation functional B3PW91 of DFT Mong with 6-31+G basis set for the PI-PH and PI-AB-Pzz complexes obtained from HF method. 展开更多
关键词 PORPHYRIN ab initio density functional theory diatomic molecules molecular storage
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The first principle study on the spectra of FPt monomer and its excimer
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作者 ZHOU Xin ZHANG HongXing PAN QingJiang 《Science China Chemistry》 SCIE EI CAS 2011年第6期968-974,共7页
The structural, electronic and spectroscopic properties of monomer FPt (2-(4′,6′-difluorophenyl)pyridinato-N,C2′)(2,4-pentanedionato-O,O) (1) and dimer [FPt]2 (2) were explored within the density functional theory ... The structural, electronic and spectroscopic properties of monomer FPt (2-(4′,6′-difluorophenyl)pyridinato-N,C2′)(2,4-pentanedionato-O,O) (1) and dimer [FPt]2 (2) were explored within the density functional theory (DFT) and time-dependent DFT (TD-DFT). The calculated geometry parameters and spectroscopic results agree well with the experimental observation. In the ground state, FPt exists in the form of monomer, while in the excited state, dimer [FPt]2 forms with a Pt-Pt contraction of 0.05 nm due to the promotion of σ[dz2(Pt2)] to π*(phenylryridyl) and σ[pz(Pt2)]. Transition properties of monomer and excimer are different in nature: the former originates from mixed transitions of 3MLCT and 3ILCT, while the latter is dominated by 3MMLCT transition. 展开更多
关键词 WOLDE luminescent properties excited state
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A first-principles study of dihydroazulene as a possible optical molecular switch 被引量:2
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作者 XIA CaiJuan LIU DeSheng LIU HanChen 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第3期437-441,共5页
By applying nonequilibrium Green's function formalism combined with first-principles density functional theory, we investigate the electronic transport properties of the dihydroazulene optical molecular switch. Th... By applying nonequilibrium Green's function formalism combined with first-principles density functional theory, we investigate the electronic transport properties of the dihydroazulene optical molecular switch. Three kinds of adsorption sites including the hollow, bridge and top sites are studied. The two forms of this molecule, namely the open form and the closed form, can reversibly switch from each other upon photoexcitation. Their transmission spectra are remarkably distinctive. Theoretical results show that the current of the closed form is always significantly larger than that of the open form for all three adsorption sites, which promises this system as possibly one of the good candidates for optical switches due to its unique advantage, and which may have some potential applications in the future molecular circuit. 展开更多
关键词 molecular switch nonequilibrium Green’s function electronic transport density functional theory
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A Derivation of the Entropy-Based Relativistic Smoothed Particle Hydrodynamics by Variational Principle
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作者 Philipe Mota Wei-Xian Chen Wei-Liang Qian 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第9期382-386,共5页
In this work, a second order smoothed particle hydrodynamics is derived for the study of relativistic heavy ion collisions. The hydrodynamical equation of motion is formulated in terms of the variational principle. In... In this work, a second order smoothed particle hydrodynamics is derived for the study of relativistic heavy ion collisions. The hydrodynamical equation of motion is formulated in terms of the variational principle. In order to describe the fluid of high energy density but of low baryon density, the entropy is taken as the base quantity for the interpolation. The smoothed particle hydrodynamics algorithm employed in this study is of the second order, which guarantees better particle consistency. Furthermore, it is shown that the variational principle preserves the translational invariance of the system, and therefore improves the accuracy of the method. A brief discussion on the potential implications of the model in heavy ion physics as well as in general relativity are also presented. 展开更多
关键词 HYDRODYNAMICS SPH method variational principle
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