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多层胶合弯曲件模压状态的分析 被引量:1
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作者 张辉 《林业科技》 北大核心 1990年第2期35-36,44,共3页
多层胶合弯曲件家具是国际80年代流行的高档家具,又称第四代椅几类家具,美国、日本、苏联、丹麦、芬兰等国产量较大。多层胶合弯曲工艺是近年发展起来的新工艺,国外以旋切或刨切单板为主要原料,通过多向高频压机压制坯件,再加工、饰涂... 多层胶合弯曲件家具是国际80年代流行的高档家具,又称第四代椅几类家具,美国、日本、苏联、丹麦、芬兰等国产量较大。多层胶合弯曲工艺是近年发展起来的新工艺,国外以旋切或刨切单板为主要原料,通过多向高频压机压制坯件,再加工、饰涂、装配制成。该工艺在国内还处于起步阶段,少数厂家利用蒸汽、高频作为热源。 展开更多
关键词 胶合弯曲件 模压状态
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Molecular Dynamics Simulations for Melting Temperatures of SrF2 and BaF2
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作者 黄晓玉 程新路 +2 位作者 樊超磊 陈琼 苑晓丽 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第3期310-314,340,共6页
The shell-model molecular dynamics method was applied to simulate the melting temper- atures of SrF2 and BaF2 at elevated temperatures and high pressures. The same method was used to calculate the equations of state f... The shell-model molecular dynamics method was applied to simulate the melting temper- atures of SrF2 and BaF2 at elevated temperatures and high pressures. The same method was used to calculate the equations of state for SrF2 and BaF2 over the pressure range of 0.1 MPa-3 GPa and 0.1 MPa-7 GPa. Compared with previous results for equations of state, the maximum errors are 0.3% and 2.2%, respectively. Considering the pre-melting in the fluorite-type crystals, we made the necessary corrections for the simulated melting temper- atures of SrF2 and BaF2. Consequently, the melting temperatures of SrF2 and BaF2 were obtained for high pressures. The melting temperatures of SrF2 and BaF2 that were obtained by the simulation are in good agreement with available experimental data. 展开更多
关键词 Molecular dynamics simulation Melting temperature Equation of state HIGHPRESSURE
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Multipartite State Representations in Multi-mode Fock Space and Their Squeezing Transformations 被引量:1
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作者 YUAN Hong-Chun LI Heng-Mei QI Kai-Guo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第1期31-34,共4页
We present the continuous state vector of the total coordinate of multi-partlcle and the state vector of their total momentum, respectively, which possess completeness relation in multi-mode Fock space by virtue of th... We present the continuous state vector of the total coordinate of multi-partlcle and the state vector of their total momentum, respectively, which possess completeness relation in multi-mode Fock space by virtue of the integration within an order product (IWOP) technique. We also calculate the transition from classical transformation of variables in the states to quantum unitary operator, deduce a new multi-mode squeezing operator, and discuss its squeezing effect. In progress, it indicates that the IWOP technique provides a convenient way to construct new representation in quantum mechanics. 展开更多
关键词 IWOP technique multipartite state representations squeezing operator
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Quantum Entanglement and Nonlocality Properties of Two-Mode Squeezed Thermal States in a Common-Reservoir Model 被引量:4
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作者 向少华 宋克慧 +1 位作者 文伟 施振刚 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第2期232-238,共7页
We study a system consisting of two identical non-interacting single-mode cavity fields coupled to a common vacuum environment and provide general, explicit, and exact solutions to its master equation by means of the ... We study a system consisting of two identical non-interacting single-mode cavity fields coupled to a common vacuum environment and provide general, explicit, and exact solutions to its master equation by means of the characteristic function method. We analyze the entanglement dynamics of two-mode squeezed thermal state in this model and show that its entanglement dynamics is strongly determined by the two-mode squeezing parameter and the purity. In particular, we find that two-mode squeezed thermal state with the squeezing parameter r ≤ -(1/2) In √u is extremely fragile and almost does not survive in a common vacuum environment. We investigate the time evolution of nonlocality for two-mode squeezed thermal state in such an environment. It is found that the evolved state loses its nonlocality in the beginning of the evolution, but after a time, the revival of nonlocality can occur. 展开更多
关键词 keytwo-mode squeezed thermal state ENTANGLEMENT Bell's inequality environmental noise
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Fluids in Mesopores: A New Theory and Applications 被引量:1
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作者 Harald Morgner 《Journal of Chemistry and Chemical Engineering》 2011年第5期456-472,共17页
While hysteresis in the adsorption of fluids in porous material is known since about one century, the thermodynamic treatment of this phenomenon is still not settled. We propose to accept that thermodynamics is not de... While hysteresis in the adsorption of fluids in porous material is known since about one century, the thermodynamic treatment of this phenomenon is still not settled. We propose to accept that thermodynamics is not designed to deal with confined systems and we propose to introduce a new set of rules for describing the behavior of confined systems. This proposal is based on a large number of simulation calculations. The employed method of simulation has been shown to describe static and dynamic phenomena encountered in this field. The newly formulated theory incorporates the phenomenon of hysteresis without inconsistencies. Further, it will be shown that the theory allows simulating diffusional and convectional transport (nanofluidics) by a unified approach without the need to introduce capillary forces (surface or interface tensions) by phenomenological parameters. The second part of the paper is devoted to the potential for practical use. It turns out that the new concepts open the route to employing unusual states of matter found in porous systems which may lead to improved applications. In particular we will focus on the possibility to drive a fluid in a pore into states with negative pressure under static and under dynamic conditions. It turns out that states with negative pressure can be reproducibly controlled. Negative pressure states are in principal known since the time of Torricelli and they have been discussed in the literature as experimentally accessible situations. Still, they have not been turned into practical usefulness which is likely to be caused by the notion of their metastability in macroscopic systems. Possible applications refer to controlling chemical reactions as well as new routes to efficient separation processes that are difficult to handle by conventional techniques. 展开更多
关键词 Mesopores thermodynamics in confined systems bistability curves of states.
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Entanglement Transfer from Two-Mode Squeezed Vacuum State Field to Two Spatially Separated Atoms in Two-Photon Processes
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作者 CUI Hui-Ping ZOU Jian LI Jian SHAO Bin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第5期1182-1186,共5页
We investigate the influence of the Stark shift on the entanglement transfer from the two-mode squeezed vacuum state field to two spatially separated atoms in two-photon processes. Our results show that the Stark shif... We investigate the influence of the Stark shift on the entanglement transfer from the two-mode squeezed vacuum state field to two spatially separated atoms in two-photon processes. Our results show that the Stark shift plays an important role in such entanglement transfer. We find that when the Stark shift parameter r is small, the degree of entanglement between the two atoms increases with the increasing of the squeezing parameter ξ first, and after achieving its maximal value, the degree of entanglement will decrease to zero with the increasing of ξ; while for big r, E will increase with the increasing of ξ. 展开更多
关键词 entanglement transfer two-mode squeezed vacuum state two-photon JCM
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Wing crack propagation model under high hydraulic pressure in compressive-shear stress state 被引量:4
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作者 ZHAO Yan-lin WANG Wen-jun 《Journal of Coal Science & Engineering(China)》 2011年第1期34-38,共5页
A new wing crack model subjected to hydraulic pressure and far-field stresses was proposed considering the effect of hydraulic pressure in wing crack and the connected part of the main crack on the stress intensity fa... A new wing crack model subjected to hydraulic pressure and far-field stresses was proposed considering the effect of hydraulic pressure in wing crack and the connected part of the main crack on the stress intensity factor at the wing crack tip. With the equivalent crack length Ieq of the wing crack introduced, the stress intensity factor Kl at the wing crack tip was as- sumed to the sum of two terms: on one hand a component K1^(1) for a single isolated straight wing crack of length 21, and subjected to hydraulic pressure in the wing crack and far-field stresses; on the other hand a component K1(2) due to the effective shear stress induced by the presence of the equivalent main crack. The lateral tensile stress and hydraulic high pressure are the key factors that induce crack propagation unsteadily. The new wing crack theoretical model proposed can supply references for the study on hydraulic fracture in fractured masses, hydraulic fracturing in rock masses. 展开更多
关键词 rock mechanics wing crack hydraulic pressure
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Revised Geometric Measure of Entanglement for Multipartite and Continuous Variable Systems 被引量:1
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作者 CAO Ya WANG An-Min 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第4期613-620,共8页
Based on the revised geometric measure of entanglement (RGME) proposed by us [J. Phys. A: Math. Theor. 40 (2007) 3507], we obtain the RGME of multipartite state including three-qubit GHZ state, W state, and the g... Based on the revised geometric measure of entanglement (RGME) proposed by us [J. Phys. A: Math. Theor. 40 (2007) 3507], we obtain the RGME of multipartite state including three-qubit GHZ state, W state, and the generalized Smolin state (GSS) in the presence of noise and the two-mode squeezed thermal state. Moreover, we compare their RGME with geometric measure of entanglement (GME) and relative entropy of entanglement (RE). The results indicate RGME is an appropriate measure of entanglement. Finally, we define the Gaussian GME which is an entangled monotone. 展开更多
关键词 quantum entanglement symmetric state revised geometric measure of entanglement relative entropy of entanglement
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Squeezing Transformation of Three-Mode Entangled State
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作者 QIAN Xiao-Qing SONG Tong-Qiang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5X期911-916,共6页
We introduce the three-mode entangled state and set up an experiment to generate it. Then we discuss the three-mode squeezing operator squeezed |p, X2, X3〉→μ^-3/2|p/μ, X2/μ, X3/μ) and the optical implement to... We introduce the three-mode entangled state and set up an experiment to generate it. Then we discuss the three-mode squeezing operator squeezed |p, X2, X3〉→μ^-3/2|p/μ, X2/μ, X3/μ) and the optical implement to realize such a squeezed state. We also reveal that c-number .asymmetric shrink transform in the three-mode entangled state, i.e. |p, X2,X3)→μ^-1/2|p/μ, X2,X3), maps onto a kind of one-sided three-mode squeezing operator {iλ (∑i^3=1 Pi) (∑i^3=1 Qi) -λ/2}. Using the technique of integration within an ordered product (IWOP) of operators, we derive their normally ordered forms and construct the corresponding squeezed states. 展开更多
关键词 three-mode entangled state c-number asymmetric shrink transform one-sided three-mode squeezing operator
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A huge thrombosed aneurysm of a saphenous vein graft leading to compression of cardiac structures: role of multimodality imaging
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作者 Byung Gyu Kim In-Cheol Kim +1 位作者 Seok-Min Kang Young-Nam Youn 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2017年第8期536-537,共2页
Aneurysmal change of saphenous vein grafts (SVG) is a rare condition that predominantly develops 10-20 years after coronary artery bypass graft (CABG). Natural course includes mechanical complications due to mass ... Aneurysmal change of saphenous vein grafts (SVG) is a rare condition that predominantly develops 10-20 years after coronary artery bypass graft (CABG). Natural course includes mechanical complications due to mass effect, myocardial infarction and aneurysmal rupture. Aneurysmectomy can be considered when it induces such complications. We demonstrate complete set of diagnosis, treatment and post-operative imaging of a huge SVG aneurysm that was successfully treated with surgical resection. 展开更多
关键词 Coronary artery bypass graft Multimodality imaging Saphenous vein graft aneurysm
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Stability Study on Hydroelectric Production Site Using Eigenvalues Analysis Method
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作者 Pedro Camilo de Oliveira e Silva Basile Kawkabani +3 位作者 Sébastien Alligné Christophe Nicolet Jean-Jacques Simond Francois Avellan 《Journal of Energy and Power Engineering》 2012年第6期940-948,共9页
The eigenvalues analysis method is generally applied to synchronous machines by using d, q-components. This paper presents the application of this method on an equivalent model for the synchronous machine based on pha... The eigenvalues analysis method is generally applied to synchronous machines by using d, q-components. This paper presents the application of this method on an equivalent model for the synchronous machine based on phase variables a, b, c instead of d, q-components. The advantages of this approach, essential for programs using phase variables as state variables, are presented. The application of this method to a complete hydroelectric production site including hydraulic components (pump-turbine, penstock, gallery, reservoir...) permits the study and analysis of the interactions between the hydraulic, electric and regulation parts of the system. Results coming from the proposed eigenvalues analysis method and the numerical simulations confirm the interest of the presented approach. 展开更多
关键词 Hydraulic systems eigenvalues and eigenfunctions power systems transient analysis.
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Ecological Security Assessment of the Yancheng National Nature Reserve based on GIS 被引量:4
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作者 LI Haiping GAO Ge LI Jing 《Journal of Resources and Ecology》 CSCD 2020年第1期38-49,共12页
This study used remote sensing and GIS to analyze the landscape pattern changes in the Yancheng Nature Reserve from 1983 to 2018,established an evaluation index system based on the regional natural-socio-economic comp... This study used remote sensing and GIS to analyze the landscape pattern changes in the Yancheng Nature Reserve from 1983 to 2018,established an evaluation index system based on the regional natural-socio-economic complex ecosystem security pattern,and then analyzed the spatial characteristics of ecological security changes and discusses reasons for these changes.The results show that the landscape pattern changed dramatically from natural landscape to a mixture of natural landscape and artificial landscape from 1983 to 2018 due to the intensification of human activities.At present,the ecological security status of the protected areas is not optimistic.From the perspective of the survival status of red-crowned cranes,the protected areas are suitable.However,due to the increase of human activities and policy adjustments,the habitat of red-crowned cranes is fragmented.The red-crowned crane currently gathers in localized areas such as the core area and the buffer zone.We should pay more attention to management,policy development and the environmental awareness of local residents.At the same time,it is necessary to reduce the intensity of human activities within the reserve. 展开更多
关键词 ecological security assessment pressure-state-response(P-S-R)model analytical hierarchy process(AHP) index weight Yancheng Nature Reserve
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Assessing the Health of Inland Wetland Ecosystems over Space and Time in China 被引量:2
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作者 YAO Yunxiao WANG Wen +1 位作者 YANG Wenting ZHANG Qihao 《Journal of Resources and Ecology》 CSCD 2021年第5期650-657,共8页
Wetland is a unique natural landscape pattern,which provides a variety of important functions and services for human societies.With the rapid develop of the economy and accelerated urbanization,the inland wetlands are... Wetland is a unique natural landscape pattern,which provides a variety of important functions and services for human societies.With the rapid develop of the economy and accelerated urbanization,the inland wetlands are faced with series of problems,including reduced area,weakened wetland functions,and deterioration of the wetland ecosystem environment.Therefore,it is necessary to quantitatively assess the ecological health of China’s inland wetlands,which is key to the sustainable development of ecosystems.However,most assessments of wetland ecosystems only examine single wetlands or watershed wetlands,and there are few assessments of wetland health at the national level.In this paper,based on land cover data,climate data,and social and economic data,an assessment system of inland wetland health is established by using the Pressure-State-Effect-Response(PSER)model,which includes 15 assessment indicators.Analytic hierarchy process(AHP)was used to define the indicator weights.Then we assessed the ecosystem health of the inland wetlands of China in 2010 and 2018,which produced three main results.(1)Unlike ecosystem health evaluated by administrative districts,wetland ecosystem health(WEH)evaluation based on the grid could provide additional details of wetland health.(2)The area of inland wetlands increased by 16328 km^(2) in 2018 compared to 2010,and the average wetland ecosystem health index in 2018 was 3.45,compared to an index value of 3.24 in 2010.(3)In 2018,wetlands in the better,good,moderate and poor conditions represented about 26.3%,46.4%,26.9%and 0.5%of the total,respectively.These results provide a practical guide for protecting and managing wetland system resources and reliable information for land use planning and development. 展开更多
关键词 WETLAND ecosystem health Pressure-State-Effect-Response AHP
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