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Entanglement capacity of two-qubit unitary operator for rank two mixed states 被引量:4
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作者 DI YaoMin LIU Li 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2007年第6期691-697,共7页
The entanglement capacity of two-qubit unitary operator acting on rank two mixed states in concurrence is discussed. The condition of perfect entangler is the same as that acting on pure states and the entanglement ca... The entanglement capacity of two-qubit unitary operator acting on rank two mixed states in concurrence is discussed. The condition of perfect entangler is the same as that acting on pure states and the entanglement capacity is the mixing parameter v1. For non-perfect entangler,the upper and lower bound of the entanglement ca-pacity are given. 展开更多
关键词 TWO-QUBIT unitary operator mixed states CONCURRENCE entanglement capacity
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The hydrothermal wave of large-Prandtl-number fluid in a shallow cavity 被引量:3
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作者 TANG ZeMei HU WenRui 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2007年第6期787-796,共10页
The hydrothermal wave was investigated numerically for large-Prandtl-number fluid (Pr = 105.6) in a shallow cavity with different heated sidewalls. The traveling wave appears and propagates in the direction opposite t... The hydrothermal wave was investigated numerically for large-Prandtl-number fluid (Pr = 105.6) in a shallow cavity with different heated sidewalls. The traveling wave appears and propagates in the direction opposite to the surface flow (upstream) in the case of zero gravity when the applied temperature difference grows and over the critical value. The phase relationships of the disturbed velocity,temperature and pressure demonstrate that the traveling wave is driven by the disturbed tem-perature,which is named hydrothermal wave. The hydrothermal wave is so weak that the oscillatory flow field and temperature distribution can hardly be observed in the liquid layer. The exciting mechanism of hydrothermal wave is analyzed and discussed in the present paper. 展开更多
关键词 hydrothermal wave numerical simulation MICROGRAVITY
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干湿纺中聚丙烯腈原丝凝固成形的探讨 被引量:3
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作者 金亮 刘栋 +2 位作者 张克勤 孙毅 郑进 《高科技纤维与应用》 CAS 2013年第6期55-59,共5页
介绍了聚丙烯腈(PAN)碳纤维原丝在以温度为主导的热致变和浓度为主导的双扩散致变下的成形过程,分析了凝固浴pH及牵伸率等对凝固成形的影响,并对干湿纺下淬火成膜,膜内液滴变化、细颈区拉伸等作出新的解释,从而对干湿纺下凝固成形的机... 介绍了聚丙烯腈(PAN)碳纤维原丝在以温度为主导的热致变和浓度为主导的双扩散致变下的成形过程,分析了凝固浴pH及牵伸率等对凝固成形的影响,并对干湿纺下淬火成膜,膜内液滴变化、细颈区拉伸等作出新的解释,从而对干湿纺下凝固成形的机理有一定的宏观把握,为纺出高品质的PAN原丝奠定理论基础。 展开更多
关键词 聚丙烯腈原丝 干湿纺 凝固成形 机理 探讨
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高职院校工业机器人技术专业的专业课程构建探讨——以宜宾职业技术学院为例 被引量:3
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作者 曾欣 朱涛 +1 位作者 陈琪 王赛 《教育教学论坛》 2017年第17期254-255,共2页
笔者通过对工业机器人行业开展调研,整理和归纳出高职工业机器人行业主要岗位(群)及典型工作任务,提出了该专业课程体系构建的思路,构建了岗位基础能力课程、岗位专项能力课程和岗位综合能力课程"三位一体"的专业课程体系,以... 笔者通过对工业机器人行业开展调研,整理和归纳出高职工业机器人行业主要岗位(群)及典型工作任务,提出了该专业课程体系构建的思路,构建了岗位基础能力课程、岗位专项能力课程和岗位综合能力课程"三位一体"的专业课程体系,以期培养出贴近企业需求的高素质技术技能型人才。 展开更多
关键词 高职院校 工业机器人技术专业 专业课程构建 探讨
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Ultrahigh spatiotemporal resolved spectroscopy 被引量:2
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作者 LI Zhi ZHANG JiaSen +1 位作者 YANG Jing GONG QiHuang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2007年第6期681-690,共10页
We review the technique and research of the ultrahigh spatiotemporal resolved spectroscopy and its applications in the field of the ultrafast dynamics of mesoscopic systems and nanomaterials. Combining femtosecond tim... We review the technique and research of the ultrahigh spatiotemporal resolved spectroscopy and its applications in the field of the ultrafast dynamics of mesoscopic systems and nanomaterials. Combining femtosecond time-resolved spectroscopy and scanning near-field optical microscopy (SNOM),we can obtain the spectra with ultrahigh temporal and spatial resolutions simultaneously. Some problems in doing so are discussed. Then we show the important applications of the ultrahigh spatiotemporal resolved spectroscopy with a few typical examples. 展开更多
关键词 ultrahigh spatiotemporal resolved spectroscopy femtosecond near-field spectroscopy scanning near-field optical microscopy (SNOM) femtosecond time-resolved NANOMATERIAL
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人非共板断面在城市道路改扩建中的运用 被引量:2
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作者 叶超 李军志 海骅 《交通与运输》 2009年第H12期14-16,共3页
结合城市道路旧城改建或道路拓宽所采取的人非共板断面工程案例,在分析人非共板断面优点及存在问题的基础上,针对城市道路改扩建中采取人非共板所存在的问题,提出了科学运用和从规划到管理的配套措施,并对人非共板的适用范围进行了探讨。
关键词 人非共板 城市道路 科学运用 探讨
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LINEAR ACTIVE STRUCTURES AND MODES (Ⅱ) —DISCRETE SYSTEMS AND BEAMS
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作者 王永刚 龚靖School of Civil Engineering and Mechanics +10 位作者 Xi'an Jiaotong University Xi'an 710049 P.R.China Department of Civil Engineering Northeast China Institute of Electric Power Jilin 132012 P.R.China 张景绘School of Civil Engineering and Mechanics Xi'an Jiaotong University Xi'an 710049 P.R.China 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第8期854-862,共9页
The basic concepts about the active structures and some attributes of the modes were presented in paper “Liner Active Structures and Modes]( I) ". The characteristics of the active discrete systems and active be... The basic concepts about the active structures and some attributes of the modes were presented in paper “Liner Active Structures and Modes]( I) ". The characteristics of the active discrete systems and active beams were discussed, especially, the stability of the active structures and the orthogonality of the eigenvectors. The notes about modes were portrayed by a model of a seven-storeyed building with sensors and actuators. The concept of the adjoint active structure was extended from the discrete systems to the beams that were the representations of the continuous structures. Two types of beams with different placements of the measuring and actuating systems were discussed in detail. One is the beam with the discrete sensors and actuators, and the other is the beam with distributed sensor and actuator function. The orthogonality conditions were derived with the modal shapes of the active beam and its adjoint active beam. An example shows that the variation of eigenvalues with feedback amplitude for the homo-configuration and non-homo-configuration active structures. 展开更多
关键词 I) ". The characteristics of the active discrete systems and active beams were discussed especially the stability of the active structures and the orthogonality of the eigenvectors. The notes about modes were portrayed by a model of a seven-s
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Numerical investigation on detonation cell evolution in a channel with area-changing cross section 被引量:1
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作者 DENG Bo HU ZongMin +1 位作者 TENG HongHui JIANG ZongLin 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2007年第6期797-808,共12页
The two-dimensional cellular detonation propagating in a channel with area-changing cross section was numerically simulated with the dispersion-controlled dissipative scheme and a detailed chemical reaction model. Eff... The two-dimensional cellular detonation propagating in a channel with area-changing cross section was numerically simulated with the dispersion-controlled dissipative scheme and a detailed chemical reaction model. Effects of the flow ex-pansion and compression on the cellular detonation cell were investigated to illus-trate the mechanism of the transverse wave development and the cellular detona-tion cell evolution. By examining gas composition variations behind the leading shock,the chemical reaction rate,the reaction zone length,and thermodynamic parameters,two kinds of the abnormal detonation waves were identified. To explore their development mechanism,chemical reactions,reflected shocks and rarefac-tion waves were discussed,which interact with each other and affect the cellular detonation in different ways. 展开更多
关键词 detonation cells transverse waves detailed chemical reaction model numerical simulation
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锅炉吹灰器问题探讨
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作者 舒安华 《江西电力》 2002年第2期29-30,34,共3页
新余电厂 30 2号炉自投产以来 ,吹灰器一直未能正常投入使用 ,这对公司搞好节能降耗 ,争创一流企业均有负面影响。笔者根据现场设备的布置及操作中存在的问题进行探讨 ,并提出改进方案。
关键词 锅炉 吹灰器 IK-3型 炉膛 火电厂
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民间资本参股金融业的发展瓶颈及对策探讨——以吉林省吉林市为例 被引量:1
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作者 陈妍 《吉林金融研究》 2015年第11期29-31,共3页
民间资本参股金融业是深化我国金融体制改革、扩大民间资本投资渠道、完善金融业公司治理机制的重要举措,其对新型金融业建设具有重要作用。本文通过分析吉林市民间资本参股金融业基本情况,探索民间资本参股金融业瓶颈障碍所在,进而提... 民间资本参股金融业是深化我国金融体制改革、扩大民间资本投资渠道、完善金融业公司治理机制的重要举措,其对新型金融业建设具有重要作用。本文通过分析吉林市民间资本参股金融业基本情况,探索民间资本参股金融业瓶颈障碍所在,进而提出切实可行的对策建议。 展开更多
关键词 民间资本 金融业 探讨
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广东省紫金县崩岗治理规划及相关问题探讨 被引量:1
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作者 丁富平 徐敬华 +2 位作者 张新和 徐小飞 赵志强 《广东水利水电》 2017年第7期24-28,共5页
崩岗治理规划基础数据数量庞大,科学地选择典型崩岗是规划的基础性工作,该文在确定规划治理目标和规模的前提下,对紫金县治理崩岗的类型、数量和面积进行了统计分析,选取了21种典型崩岗,并对典型崩岗治理措施工程量进行了表格化和统一... 崩岗治理规划基础数据数量庞大,科学地选择典型崩岗是规划的基础性工作,该文在确定规划治理目标和规模的前提下,对紫金县治理崩岗的类型、数量和面积进行了统计分析,选取了21种典型崩岗,并对典型崩岗治理措施工程量进行了表格化和统一化处理,确定了全县崩岗治理规划总工程量和总投资等。最后结合实践对崩岗治理规划的相关问题进行了讨论。 展开更多
关键词 崩岗 治理 规划 探讨
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Single Crystal Growth and Magnetoresistivity of Topological Semimetal CoSi
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作者 D.S.Wu Z.Y.Mi +6 位作者 Y.J.Li W.Wu P.L.Li Y.T.Song G.T.Liu G.Li J L.Luo 《Chinese Physics Letters》 SCIE CAS CSCD 2019年第7期77-81,共5页
We report single crystal growth of CoSi, which has recently been recognized as a new type of topological semimetal hosting fourfold and sixfold degenerate nodes. The Shubnikov–de Haas quantum oscillation(QO) is obser... We report single crystal growth of CoSi, which has recently been recognized as a new type of topological semimetal hosting fourfold and sixfold degenerate nodes. The Shubnikov–de Haas quantum oscillation(QO) is observed on our crystals. There are two frequencies originating from almost isotropic bulk electron Fermi surfaces, in accordance with band structure calculations. The effective mass, scattering rate, and QO phase difference of the two frequencies are extracted and discussed. 展开更多
关键词 SINGLE CRYSTAL GROWTH been recognized as extracted and discussed
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Sealing the Fate of International Mail -Unprecedented Strucural Reforms Discussed at Universal Postal Conference
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《China Today》 1999年第12期43-45,共3页
关键词 US Unprecedented Strucural Reforms discussed at Universal Postal Conference Sealing the Fate of International Mail
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农机化是发展现代农业的必由之路
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作者 许景诚 《湖南农机(学术版)》 2008年第2期40-40,42,共2页
农业机械化是农业现代化的重要组成部分。本文结合辽阳市农业和农机发展的实际,论述了农机化在建设现代农业中的地位和作用。
关键词 农机化 现代农业
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The assessment of time dependent flow of Williamson fluid with radiative blood flow against a wedge
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作者 K.Subbarayudu S.Suneetha P.Bala Anki Reddy 《Propulsion and Power Research》 SCIE 2020年第1期87-99,共13页
The present pagination reports both Brownian diffusion and thermophoresis aspects subject to magneto hydrodynamic Williamson fluid model.Assuming the flow is unsteady and blood is treated as Williamson fluid over a we... The present pagination reports both Brownian diffusion and thermophoresis aspects subject to magneto hydrodynamic Williamson fluid model.Assuming the flow is unsteady and blood is treated as Williamson fluid over a wedge with radiation.The governing equations are transformed into ordinary differential equations by using similarity variables.The analytical solutions of the transformed governing equations are obtained by using the RK 4th order method along with shooting technique solver.The effects of various physical parameters such as Hartmann number,local Weissenberg number,radiation parameter,unsteadiness parameter,Prandtl number,Lewis number,Brownian diffusion,thermophoresis,wedge angle parameter,moving wedge parameter,on velocity,temperature,concentration,skin friction,heat transfer rate and mass transfer rate have been discussed in detail.The velocity and temperature profile deprives for larger We and an opposite trend is observed for concentration.The radiation parameter is propositional to temperature and a counter behaviour is observed for Pr. 展开更多
关键词 The present pagination reports both Brownian diffusion and thermophoresis aspects subject to magneto hydrodynamic WILLIAMSON fluid model. Assuming the flow IS unsteady and blood IS treated as WILLIAMSON fluid over a WEDGE with radiation. The governing EQUATIONS are transformed into ordinary differential EQUATIONS by using similarity variables. The analytical solutions of the transformed governing EQUATIONS are obtained by using the RK 4th order method along with shooting technique solver. The effects of various physical parameters such as Hartmann NUMBER local Weissenberg NUMBER radiation PARAMETER unsteadiness PARAMETER Prandtl NUMBER Lewis NUMBER Brownian diffusion thermophoresis WEDGE angle PARAMETER moving WEDGE PARAMETER on velocity temperature concentration skin friction heat transfer rate and mass transfer rate have been discussed in detail. The velocity and temperature profile deprives for larger We and an opposite trend IS observed for concentration. The radiation PARAMETER IS propositional to temperature and a counter behaviour IS observed for Pr.
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配煤掺烧产生问题的解决方案和经济性探讨
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作者 王连石 《黑龙江科技信息》 2013年第34期32-33,共2页
为了确保电力企业良性发展、降低发电成本、提高企业经济效益,同时保证机组的安全、稳定、经济的运行,调配燃煤、做到混煤掺烧是越来越多的大型电厂的优先选择。本文根据大唐七台河发电有限公司褐煤掺烧以来发生的问题和解决方案和经济... 为了确保电力企业良性发展、降低发电成本、提高企业经济效益,同时保证机组的安全、稳定、经济的运行,调配燃煤、做到混煤掺烧是越来越多的大型电厂的优先选择。本文根据大唐七台河发电有限公司褐煤掺烧以来发生的问题和解决方案和经济型尽心过了探讨,并提出了相应的掺烧建议。 展开更多
关键词 褐煤 掺烧 问题 经济性 探讨
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The influence of the revision of the Port State Control Procedure 2017
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作者 Zhang Shulei Le Yongfeng Zhuang Xin 《中国船检》 2018年第3期120-121,共2页
At the end of 2017, the IMO Assembly discussed and adopted the “2017 port state supervision procedure” A.1119 (30). The content of the new procedure is more rich and rigorous. By studying and identifying the importa... At the end of 2017, the IMO Assembly discussed and adopted the “2017 port state supervision procedure” A.1119 (30). The content of the new procedure is more rich and rigorous. By studying and identifying the important points of the Procedure, it can be found that it has the following new features: 展开更多
关键词 the IMO ASSEMBLY discussed and adopted
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对《压力容器波形膨胀节》2018版新标准的理解及分析
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作者 郑院梅 刘利武 匡良明 《中国特种设备安全》 2021年第9期51-55,共5页
针对GB/T 16749-2018《压力容器波形膨胀节》最新版的修订内容,提出几个在应用过程中经常遇到的诸如成形减薄量、成形变形率、疲劳累计损伤、HZ型膨胀节不适应疲劳工况、直边长度、许用疲劳次数等有关问题及其相关理解.借鉴国外EJMA、AS... 针对GB/T 16749-2018《压力容器波形膨胀节》最新版的修订内容,提出几个在应用过程中经常遇到的诸如成形减薄量、成形变形率、疲劳累计损伤、HZ型膨胀节不适应疲劳工况、直边长度、许用疲劳次数等有关问题及其相关理解.借鉴国外EJMA、ASME VⅢ-1&2和EN 13445-3标准进行分析,并对解决方案进行探讨。将有助于大家对新标准的理解和运用,也为今后对标准内容的进一步完善和适应范围的进一步扩大提供一定的参考。 展开更多
关键词 膨胀节 EJMA 波纹管 探讨 分析
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一种吡唑啉酮类化合物的合成研究
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作者 于锦亮 豆静杰 +1 位作者 杨宗义 张占国 《信息记录材料》 2019年第9期32-34,共3页
吡唑啉酮是化工合成的重要中间体.本文介绍了以2-乙酰基丁二酸二甲酯为原料,通过与2,4-二磺酸苯基重氮盐缩合成腙,然后碱性闭环制得最终产物.对此化合物的合成条件和影响因素进行讨论研究.
关键词 吡唑啉酮 合成 讨论
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The critical behavior of shear modulus in solid-liquid mixing phase
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作者 RAN XianWen TANG WenHui +1 位作者 TAN Hua DAI ChengDa 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2007年第6期742-746,共5页
The behavior of shear modulus in solid-liquid mixing phase has been discussed and analyzed. The result was concluded that shear modulus went to zero as the melting mass ratio attained a critical value. The percolation... The behavior of shear modulus in solid-liquid mixing phase has been discussed and analyzed. The result was concluded that shear modulus went to zero as the melting mass ratio attained a critical value. The percolation theory model we pro-posed showed that this value was about 0.68742. The melting-induced destabilizing factor of material proposed by us can represent phenomenologically the change of shear modulus in melting process. 展开更多
关键词 solid-liquid mixing phase critical behavior shear modulus destabilizing factor
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