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Next Frontier in Physics—Space as a Complex Tension Field 被引量:1
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作者 Chandrasekhar Roychoudhuri 《Journal of Modern Physics》 2012年第10期1357-1368,共12页
We hypothesize that 100% of the energy of our cosmic system is held by a physically real Complex Tension Field (CTF). We are using an old methodology of thinking used by our forefather engineers long before the advent... We hypothesize that 100% of the energy of our cosmic system is held by a physically real Complex Tension Field (CTF). We are using an old methodology of thinking used by our forefather engineers long before the advent of modern scientific thinking. We call it Interaction Process Mapping Epistemology or IPM-E. We apply this IPM-E on to the prevailing Measurable Data Modeling Epistemology or MDM-E. This approach helped us analyze the “Measurement Problem”, recognized during the rise of quantum mechanics (QM), and helped us recover a universal property of all linear waves, that they do not interact, or interfere, with each other. This Non-Interaction of Waves, or the NIW-property, should be obvious through daily observations and through the Huygens-Fresnel diffraction integral and through critical evaluation of contradictory hypotheses we have been assigning to photons through ages. This implicates that the time-frequency Fourier theorem, although mathematically correct, and is used universally in all branches of science;does not map the real physical interaction processes for most optical phenomena. Accordingly, we present the necessary modifications for a few selected phenomena in classical and quantum optics to validate the NIW-property. In the process we find that accepting photons as non-interacting, but diffractively propagating linear wave packets crossing the entire cosmic space, requires CTF as a physical medium. Then we develop logical arguments in support of stable elementary particles as nonlinear but resonant vortex-like undulations of this same CTF. These vortex-like particles impose various secondary potential gradients around themselves giving rise to the four forces we know. Thus, CTF can serve as the cosmic substrate to develop a unified field theory without the need of dark matter and dark energy. In the process, we demonstrate a path to add ontologic thinking on our biologically successful epistemic thinking. 展开更多
关键词 Non-Interaction of Waves COSMIC tension field DARK Energy and MATTER Platform for UNIFIED field Theory
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Cosmic Ether, Possessing Electric-Tension and Magnetic-Resistance, Is the Unified Field for Physics 被引量:1
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作者 Chandrasekhar Roychoudhuri 《Journal of Modern Physics》 2021年第5期671-699,共29页
The paper presents the case that physics is already and effectively unified by the energetic tension field, ether. We identify this integrating power of ether first, by re-defining the action generating parameters of ... The paper presents the case that physics is already and effectively unified by the energetic tension field, ether. We identify this integrating power of ether first, by re-defining the action generating parameters of this energetic tension field as the electric-tension, <img src="Edit_1233fa02-9a1c-416a-8153-196733a12887.png" alt="" />, and the magnetic-resistance, <em>μ</em><sub>0</sub>, while re-deriving the Maxwell’s wave equation in analogy with the mechanically stretched string, where the <img src="Edit_07813a1b-d94f-4e68-a3ed-b3023cd3fb5f.png" alt="" />. Then, replacing <img src="Edit_7d06fa1e-760d-4b80-a503-db81378a3512.png" alt="" /> by <img src="Edit_58f15ef0-2e86-42ae-a899-d0b4741f12d0.png" alt="" /> and <em>m</em><sub>0</sub> by <img src="Edit_f8cb7020-1a27-404a-b146-5c1357e1c5b5.png" alt="" />, one can find that almost all working physics theories are being energized by<img src="Edit_f860fcdd-1dc1-40bf-aaf1-e07b0e4a7524.png" alt="" />and <em>μ</em><sub>0</sub>. To complete the unification, we can now postulate that the particles are also freely propagating EM waves, but they are spatially localized as in-phase, close-looped (IP-CL) vortex-like propagation modes of ether. Because of their IP-CL mode structure, they have space-finite spatial structures and remain spatially stationary in the absence of any spatially influencing potential gradients (forces) in their vicinity. Particles’ <em>harmonic phase</em> driven interactions between quantum particles give birth to the <em>appearance</em> of wave-particle duality. There is no need for the confusing and unnecessary de Broglie’s Pilot Wave. The inertia to spatial motion of IP-CL modes automatically accommodates Newton’s laws of motion. The cosmic universality of Maxwellian wave velocity, and particles as IP-CL modes, jointly accommodate the two key postulates of special relativity without the need for unphysical four-dimensionality. The observable universe is represented only by its diverse oscillatory excited states. The stable and stationary Cosmic Ether keeps holding 100% of its energy all the time. We have proposed a one-way light pulse propagation experiment to directly validate the existence of ether, rather than approaching Michelson’s way of measuring the ether drag. We have identified a good number of examples of working theoretical expressions in terms of <img src="Edit_fd739625-efbd-4edd-9e1e-ba4ab5b7c07f.png" alt="" />and<em> μ</em><sub>0</sub> and presented our critical views in physics thinking, belonging to Classical, Relativity, Quantum and Cosmology Physics. 展开更多
关键词 Cosmic Ether Ether as the Unifying field Ether Energetic tension field (1/ε0)-Electric tension of Ether μ0-Magnetic Resistance of Ether Particles as Localized EM Oscillating Modes of Ether
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Comparison of corneal biomechanical properties in normal tension glaucoma patients with different visual field progression speed 被引量:4
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作者 Ying Hong Nobuyuki Shoji +4 位作者 Tetsuya Morita Kazunori Hirasawa Kazuhiro Matsumura Masayuki Kasahara Kimiya Shimizu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第7期973-978,共6页
AIM:To compare the corneal biomechanical properties difference by ocular response analyzer(ORA) in normal tension glaucoma(NTG) patients with different visual field(VF) progression speed. METHODS:NTG patients ... AIM:To compare the corneal biomechanical properties difference by ocular response analyzer(ORA) in normal tension glaucoma(NTG) patients with different visual field(VF) progression speed. METHODS:NTG patients with well-controlled Goldmann applanation tonometer(GAT) who routinely consulted Kitasato University Hospital Glaucoma Department between January 2010 and February 2014 were enrolled.GAT and ORA parameters including corneal compensated intraocular pressure(lOPcc),Goldmann estimated intraocular pressure(lOPg),corneal hysteresis(CH),corneal resistance factor(CRF) were recorded.VF was tested by Swedish interactive threshold algorithm(SITA)-standard 30-2 fields.All patients underwent VF measurement regularly and GAT did not exceed 15 mm Hg at any time during the 3y follow up.Patients were divided into four groups according to VF change over 3y,and ORA findings were compared between the upper 25th percentile group(slow progression group) and the lower 25th percentile group(rapid progression group).RESULTS:Eighty-two eyes of 56 patients were studied.There were 21 eyes(21 patients) each in rapid and slow progression groups respectively.GAT,lOPcc,lOPg,CH,CRF were 12.1+1.4 mm Hg,15.8±1.8 mm Hg,12.8±2.0 mm Hg,8.4±1.1 mm Hg,7.9±1.3 mm Hg respectively in rapid progression group and 11.5±1.3 mm Hg,13.5±2.1 mm Hg,11.2±1.6 mm Hg,9.3±1.1 mm Hg,8.2±0.9 mm Hg respectively in slow progression group(P=0.214,〈0.001,0.007,0.017,0.413,respectively).In bivariate correlation analysis,lOPcc,lOPcc-GAT and CH were significant correlated with m△MD(r =-0.292,-0.312,0.228 respectively,P =0.008,0.004,0.039 respectively).CONCLUSION:Relatively rapid VF progression occurred in NTG patients whose lOPcc are rather high,CH are rather low and the difference between lOPcc and GAT are relatively large.Higher lOPcc and lower CH are associated with VF progression in NTG patients.This study suggests that GAT measures might underestimate the IOP in such patients. 展开更多
关键词 ocular response analyzer intraocular pressure corneal biochemical properties visual field normal tension glaucoma
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Effects of alternative electromagnetic field on surface tension and filling ability of molten metal
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作者 何洪亮 康福伟 王丽萍 《中国有色金属学会会刊:英文版》 CSCD 2005年第3期548-552,共5页
Surface tension and filling ability of molten metal play an important role on the shaping of the molten metal. The surface tension was calculated from wetting angles of the molten metal by the sessile drop method. The... Surface tension and filling ability of molten metal play an important role on the shaping of the molten metal. The surface tension was calculated from wetting angles of the molten metal by the sessile drop method. The specimen for filling ability was designed and the filling ability experiments under the alternative electromagnetic field were performed. The results show that the intensity and frequency of the alternative electromagnetic field have significant effects on the surface tension of the molten metal. The surface tension of Al-6%Si alloy decreases with increasing the intensity of the electromagnetic field. For pure Sn, the surface tension decreases gradually when the frequency of electromagnetic field is reduced. The filling ability is improved by applying the alternative electromagnetic field. 展开更多
关键词 电磁场 表面张力 湿润角 铝-硅合金 复合材料
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Studying of Kinematics and Elements of Tension of Blocks of the Massif According to Field Geological Observations
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作者 R. A. Umurzakov M. Yu. Muminov 《World Journal of Mechanics》 2017年第9期243-254,共12页
The description of the received new results of field geological (teсtonophysical) study of massifs of rocks is provided: tectonic jointing, explosive and folded deformations, mirrors of slidings, tectonic motions of ... The description of the received new results of field geological (teсtonophysical) study of massifs of rocks is provided: tectonic jointing, explosive and folded deformations, mirrors of slidings, tectonic motions of blocks of breeds. Reconstruction of fields of tension according to geological data of the certain massif of the Chatkalo-Kurama mountain area (Tien-Shan)—a coastal zone of the Charvak reservoir and the Almalyk mining industrial region is executed. The multidirectional motions of blocks of rocks in the massif of a coastal zone of the Charvak reservoir connected with tectonic and technogenic factors are revealed. The scheme of kinematics and the intense deformed condition of blocks of the Almalyk district is received. Here the regional field of tension with horizontal and submeridional orientation of an axis of the main normal tension of compression at the inclined provision of two other axes are observed. The received results testify to opportunities field the tectonophysical of methods for obtaining important data on kinematics and dynamics of massifs of rocks, tectonic blocks, and features of their deformation. Such studying of the massif of rocks before the beginning and in the course of performance of work on objects of the national economy is important for the choice of design and optimum parameters of laying of excavations, control of a condition of their boards and walls, definition of strategy of safety of conducting mining operations and also seismic stability of constructions. 展开更多
关键词 MASSIF of ROCKS Structure KINEMATICS Dynamics Tectonophysics Deformations Mirrors of Slidings field of tension
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Application of Tension Leg Platform Combined with Other Systemsin the Development of China Deepwater Oil Fields 被引量:2
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作者 张大刚 《China Ocean Engineering》 SCIE EI 2006年第4期517-528,共12页
The development of deepwater oil fields has reached a new stage with the dramatic increase in water depth and the recent increasing demands of the economic development in the filed. The use of a Tension Leg Platform ... The development of deepwater oil fields has reached a new stage with the dramatic increase in water depth and the recent increasing demands of the economic development in the filed. The use of a Tension Leg Platform (TIP) combined with other systems, such as Floating Production Storage and Offloading (FPSO) system, Floating Production Unit (FPU) system, Tender Assisted Drilling (TAD) system, etc., has drawn the industry attention and increased significantly in the past few years. For the areas lacking of pipeline system, the use of TIP(s) combined with FPSO has been chosen to efficiently develop the deepwater fields. The TIP with a Tender Assisted Drilling system significantly reduces the payload of the platform and reduces the investment in the TIP system substantially. This opens the door for many new deepwater field developments to use the tension leg platform. The advantage of the TIP combined with a TAD system is more significant when several TIPs are used for the continuous development of the field. One of the applications for the TIP with a tender assisted drilling system can be in the development of an offshore marginal field. Owing to the increase of water depth, the conventional fixed platform model for the exploration of those fields becomes uneconomical. It also would be too expensive to use a large TIP structure for those marginal fields due to the large amount of initial investment. The TIP system with tender assisted drilling can be used to develop those fields economically. There are many marginal fields in China offshore, especially in shelf areas. The application of this field developing model, combined with the existing field developing experience in China, will open the door for many marginal field developments. This paper will review the application of the combined TIP system through some examples of completed/ongoing projects, and major technical issues encountered in those practices. The potential application of this technology in China deepwater development will be discussed in the end. 展开更多
关键词 tension leg platform combined system tender assisted drilling platform structure field development DEEPWATER
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线黏弹性材料数字图像相关实验教学探索
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作者 苏昂 张大鹏 +2 位作者 张文沁 关棒磊 李璋 《力学与实践》 2024年第1期201-207,共7页
线黏弹性理论是固体力学原理课程的重要内容,目前实验教学一般采用电子万能试验机对线黏弹性材料进行单轴拉伸实验,实验结果不够直观。数字图像相关方法是一种高精度全场应变测量方法,近年来在实验力学领域应用广泛。本文以固体推进剂... 线黏弹性理论是固体力学原理课程的重要内容,目前实验教学一般采用电子万能试验机对线黏弹性材料进行单轴拉伸实验,实验结果不够直观。数字图像相关方法是一种高精度全场应变测量方法,近年来在实验力学领域应用广泛。本文以固体推进剂这种线黏弹性材料为例,采用数字图像相关方法设计了线黏弹性材料单轴拉伸实验,实现了全场变形测量并且实验结果可视化更直观,有助于调动学生积极性。实验发现,数字图像相关方法与国标规定的固体推进剂单向拉伸法测量的材料应变有明显差异,针对该问题设计了实验教学研讨环节,引导学生深入分析,有助于加深对线黏弹性理论的理解。 展开更多
关键词 数字图像相关 线黏弹性 单轴拉伸 全场测量 实验教学
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氟表面活性剂的合成及油田应用的最新进展(续完)
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作者 肖进新 《日用化学品科学》 CAS 2024年第4期11-19,共9页
1.5 gemini型氟表面活性剂.gemini表面活性剂因其独特的化学结构而广受关注。传统表面活性剂为单头单尾,而gemini表面活性剂则是双头双尾,头基间通过间隔基连结。gemini表面活性剂的物理化学性质包括较低的cmc和高于单体(常规)表面活性... 1.5 gemini型氟表面活性剂.gemini表面活性剂因其独特的化学结构而广受关注。传统表面活性剂为单头单尾,而gemini表面活性剂则是双头双尾,头基间通过间隔基连结。gemini表面活性剂的物理化学性质包括较低的cmc和高于单体(常规)表面活性剂的表面性能。为寻找长碳氟链氟表面活性剂的替代品,Du等合成了一系列含有全氟醚链的gemini表面活性剂,并对其表面张力进行了研究。采用酰胺化反应和季铵化反应两步合成了gemini表面活性剂。在第1步中,N,N-二甲基-1,3-丙二胺分别与氟化酯或酰氟反应生成氟化酰胺中间体。第2步,该中间体与二溴化物反应,通过季铵化得到gemini表面活性剂(图17)[46]。 展开更多
关键词 氟表面活性剂 全氟 表面张力 物理化学性质 表面性能 替代品 油田应用
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基于自抗扰控制的圆纬机恒张力输纱控制系统设计
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作者 彭来湖 谢国旺 戴宁 《纺织学报》 EI CAS CSCD 北大核心 2024年第1期211-219,共9页
针对当前圆纬机积极式送纱方式中存在的纱线张力及输送速度不可任意调节、纱线张力波动大等问题,提出了一种可为圆纬机输送恒定张力纱线的输纱控制系统。构建了以无刷直流电动机速度环为内环、以纱线张力为外环的纱线恒张力双闭环反馈... 针对当前圆纬机积极式送纱方式中存在的纱线张力及输送速度不可任意调节、纱线张力波动大等问题,提出了一种可为圆纬机输送恒定张力纱线的输纱控制系统。构建了以无刷直流电动机速度环为内环、以纱线张力为外环的纱线恒张力双闭环反馈控制系统,通过自抗扰控制技术获取纱线实时动态指标,并对无刷直流电动机目标转速进行调整,最后通过磁场定向控制技术驱动无刷直流电动机。详细阐述了纱线张力的形成机制、纱线恒张力输送控制方案、系统硬件设计及控制算法。输纱测试表明,该控制系统可实现多种类型纱线的恒定张力输送。其中,棉纱张力波动标准差为1.5 cN(300 m/min测试条件),氨纶包芯纱的张力波动标准差为0.33 cN(240 m/min测试条件)。输纱速度的调节范围为0~600 m/min,纱线张力的控制范围为2.0~50.0 cN。 展开更多
关键词 恒张力 输纱器 无刷直流电动机 磁场定向控制 自抗扰控制 圆纬机
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寻找“正确的”剧场性——中国话剧“剧场性”观念概评
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作者 方桂林 《民族艺术研究》 2024年第4期57-63,共7页
中国话剧的“剧场性”观念在新时期之前主要指涉的是舞台性,即合乎剧场与舞台的特征。新时期以来,剧场性的内涵与假定性、交流性、表演性、物质空间、观演关系紧密联系在一起,剧场性与文学性的矛盾与争论也在这个时候开始显现。在“后... 中国话剧的“剧场性”观念在新时期之前主要指涉的是舞台性,即合乎剧场与舞台的特征。新时期以来,剧场性的内涵与假定性、交流性、表演性、物质空间、观演关系紧密联系在一起,剧场性与文学性的矛盾与争论也在这个时候开始显现。在“后戏剧剧场”的语境中,剧场性是“文本之外的剧场过程”。故此,中国话剧“剧场性”观念的变迁具有历时性,要在历史与当下的对比中把握主流。同时,剧场性既是一种主观的美学追求,又是一种客观属性。观众对于剧场性的感知是多种因素综合作用的结果。“正确的”剧场性没有一个恒定的标尺,是“用适合的演剧方式来奉献戏剧作品”,是在主观与客观里寻求融合。 展开更多
关键词 中国话剧 剧场性 舞台性 张力 符号学
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千米深井煤层水力压裂作用下裂隙应力场演化规律的数值模拟研究
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作者 李延辉 《能源与环保》 2024年第4期32-37,43,共7页
为了掌握千米深井煤层水力压裂作用下煤体内部裂隙应力场演化规律,更科学地开展超千米矿井煤层水力压裂增透瓦斯综合治理工作,以平煤股份一矿超千米埋深的戊8-31240工作面为建模背景,采用RFPA-2D数值模拟软件,建立了煤体内部裂隙发育—... 为了掌握千米深井煤层水力压裂作用下煤体内部裂隙应力场演化规律,更科学地开展超千米矿井煤层水力压裂增透瓦斯综合治理工作,以平煤股份一矿超千米埋深的戊8-31240工作面为建模背景,采用RFPA-2D数值模拟软件,建立了煤体内部裂隙发育—应力场扰动数值模型,模拟得到了水力压裂作用下深部煤体内部裂隙应力场演化过程。研究结果表明,深部煤体内部在水力压裂作用下,首先由水流浸润煤体,微裂隙在压裂孔四周区域萌生,在孔左上、右上两侧区域形成“V”形主级宏观裂隙呈扇形继续扩展发育,然后在孔左下、右下两侧区域微裂隙贯通形成“Λ”形次级宏观裂隙,最后孔两侧主、次级宏观裂隙贯通,呈现“X”形裂隙扩展主导压裂,并产生更多微裂隙,使深部煤体受水力压裂的影响范围不断扩大;深部煤体水力压裂开始阶段,内部破坏向压裂孔四周随机发生,随着压裂压力升高,煤体破坏开始向压裂孔上下区域延伸,但远小于向压裂孔两侧破坏速度,煤体破坏更多集中在煤层上部,表明水力压裂将会对煤层顶板造成较大冲击;深部煤体受水力压裂作用,条带状剪应力、块状拉应力主要集中在裂隙的尖端附近区域,剪应力从13.5 MPa卸压到1.1 MPa,卸压降幅91%,而拉应力从11.0 MPa卸压到2.2 MPa,卸压降幅80.0%,其拉应力卸压效果要小于剪应力的卸压效果,随着压裂的裂隙向煤体深部延伸转移,最终在单个压裂孔前后25 m范围区域形成剪—拉双重作用卸压区,使地应力得到释放,大大提高了深部煤体的透气性。数值模拟研究可为千米矿井深部煤层水力压裂技术工艺参数优化实施提供一定参考。 展开更多
关键词 千米深井 水力压裂 裂隙应力场演化 剪—拉双重作用卸压区 数值模拟
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500 kV双联耐张瓷绝缘子串的串间放电现象
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作者 程洋 夏令志 +4 位作者 牛雷 阮巍 孙昊 曹轩赫 张世珉 《中国电力》 CSCD 北大核心 2024年第9期231-237,共7页
以某换流站500 kV出线双联耐张瓷绝缘子串为研究对象,研究了双联瓷绝缘子串串间放电现象的成因。开展了电阻测试、剖面染色等实验,建立了双联瓷绝缘子串电场与放电仿真模型,获得了双联绝缘子串空间电场分布规律。研究结果表明:水汽侵入... 以某换流站500 kV出线双联耐张瓷绝缘子串为研究对象,研究了双联瓷绝缘子串串间放电现象的成因。开展了电阻测试、剖面染色等实验,建立了双联瓷绝缘子串电场与放电仿真模型,获得了双联绝缘子串空间电场分布规律。研究结果表明:水汽侵入水泥黏合剂缝隙导致多个绝缘子阻值下降形成大量零值绝缘子(西侧20片、东侧4片)。由于两侧零值绝缘子数量差距较大,产生122 kV串间电位差是串间放电的主要成因。 展开更多
关键词 双联耐张瓷绝缘子串 零值绝缘子 电场分布 串间放电
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硅钢脱碳退火机组卷取机弱磁区张力优化
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作者 刘沛迪 孙俊 熊金乐 《电工钢》 CAS 2024年第2期31-36,共6页
由于近期硅钢市场需求强劲,连续退火机组投产10年后面临提速、提质的要求,材质单层越来越薄,整卷后工序成材率、让步率,受到卷取张力的影响越来越明显,通过研究张力控制的原理及张力优化方案、建立实际作用于带钢卷取的张力模型,逐步排... 由于近期硅钢市场需求强劲,连续退火机组投产10年后面临提速、提质的要求,材质单层越来越薄,整卷后工序成材率、让步率,受到卷取张力的影响越来越明显,通过研究张力控制的原理及张力优化方案、建立实际作用于带钢卷取的张力模型,逐步排查出处于弱磁区的卷取机异步电机转矩精度、线性度不足,针对电机传动(逆变器)、PLC程序的优化使得转矩精度达到工艺的要求。 展开更多
关键词 连续脱碳退火机组 张力控制模型 异步电机 弱磁控制 逆变器
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基于ANSYS的电力耐张线夹监测装置热-结构耦合有限元分析
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作者 马波 郑伟 +2 位作者 焦晓鹏 朱奕弢 吴松 《电工技术》 2024年第11期85-90,共6页
耐张线夹是架空输电线路的重要组成部件之一,其损坏导致电力系统安全运行成本的增加,因此需要大量相关监测装置。设计了一款耐张线夹监测装置,用于耐张线夹运行状况的监测。利用ANSYS对装置进行环境载荷下的热-结构耦合的有限元分析,记... 耐张线夹是架空输电线路的重要组成部件之一,其损坏导致电力系统安全运行成本的增加,因此需要大量相关监测装置。设计了一款耐张线夹监测装置,用于耐张线夹运行状况的监测。利用ANSYS对装置进行环境载荷下的热-结构耦合的有限元分析,记录监测装置在不同安装接触情况下各部位的应力和变形,所得结果表明面接触安装方式优于点接触和线接触。选取面接触安装方式与NY400型耐张线夹三维模型完成装配,进行引流板接触位置180℃情况下的瞬态热有限元分析,获取监测装置对引流板接触位置温度变化的响应情况。 展开更多
关键词 耐张线夹 监测装置 温度场分布 有限元分析 热-结构耦合
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夸克物质相变中气泡和液滴形成与演化的研究
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作者 石浚希 毛鸿 舒崧 《大学物理》 2024年第8期42-48,63,共8页
本文利用有限温度场论的方法及Friedberg-Lee模型,推导了有限温度下夸克物质相变过程中的有效势,场方程以及气泡和液滴的物理学量相关公式,并在不同边界条件下采用数值方法严格求解出了气泡解与液滴解.结合气泡或液滴核合成唯象模型,分... 本文利用有限温度场论的方法及Friedberg-Lee模型,推导了有限温度下夸克物质相变过程中的有效势,场方程以及气泡和液滴的物理学量相关公式,并在不同边界条件下采用数值方法严格求解出了气泡解与液滴解.结合气泡或液滴核合成唯象模型,分析了气泡和液滴在相变过程中的形成机制,讨论了其对相变的影响.同时利用数值结果研究了气泡和液滴的物理性质,并将两类结果进行了对比,阐明了气泡或液滴在相变过程中的变化规律和物理图像. 展开更多
关键词 夸克禁闭模型 有限温度场论 气泡动力学 表面张力
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Liquid crystal model of vesicle deformation in alternating electric fields
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作者 Yugang Tang Ying Liu Qingshan Yang 《Theoretical & Applied Mechanics Letters》 CAS 2013年第5期45-48,共4页
Considering the effects of osmotic pressure, elastic bending, Maxwell pressure, surface tension, as well as flexo-electric and dielectric properties of phospholipid membrane, the shape equation for sphere vesicle in a... Considering the effects of osmotic pressure, elastic bending, Maxwell pressure, surface tension, as well as flexo-electric and dielectric properties of phospholipid membrane, the shape equation for sphere vesicle in alternation (AC) electric field is derived based on the liquid crystal model by minimizing the free energy due to coupled mechanical and AC electrical fields. Besides the effect of elastic bending, the influence of osmotic pressure and surface tension on the frequency dependent behavior of vesicle membrane in AC electric field is also discussed. Our theoretical results for membrane deformation are consistent with corresponding experiments. The present model provides the possibility to further disclose the frequency-depended behavior of biological cells in the coupled AC electric and different mechanical fields. 展开更多
关键词 liquid crystal model vesicle shape AC electric field osmotic pressure surface tension frequency-dependent
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Normal tension glaucoma: from the brain to the eye or the inverse? 被引量:6
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作者 Hui-Jun Zhang Xue-Song Mi Kwok-Fai So 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第11期1845-1850,共6页
Glaucoma is a chronic, progressive optic neuropathy characterized by the loss of peripheral vision first and then central vision. Clinically, normal tension glaucoma is considered a special subtype of glaucoma, in whi... Glaucoma is a chronic, progressive optic neuropathy characterized by the loss of peripheral vision first and then central vision. Clinically, normal tension glaucoma is considered a special subtype of glaucoma, in which the patient’s intraocular pressure is within the normal range, but the patient experiences typical glaucomatous changes. However, increasing evidence has challenged the traditional pathophysiological view of normal tension glaucoma, which is based only on intraocular pressure, and breakthroughs in central nervous system imaging may now greatly increase our knowledge about the mechanisms underlying normal tension glaucoma. In this article, we review the latest progress in understanding the pathogenesis of normal tension glaucoma and in developing imaging techniques to detect it, to strengthen the appreciation for the connection between normal tension glaucoma and the brain. 展开更多
关键词 NERVE REGENERATION normal tension GLAUCOMA open angle GLAUCOMA NEURODEGENERATIVE diseases visual field CEREBROSPINAL fluid pressure IMAGING techniques pathogenesis magnetic resonance IMAGING diffusion tensor IMAGING metabolic changes neural REGENERATION
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高速永磁电机转子护套张力缠绕激光加热成型过程多物理场耦合分析
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作者 薄凯 苏维国 +2 位作者 陈俊全 王东 孙文 《中国电机工程学报》 EI CSCD 北大核心 2023年第20期8073-8081,共9页
随着舰船综合电力系统对电机转速和功率需求的不断增大,传统非导磁金属材料已难以满足大功率高速永磁电机护套机械强度要求,热塑性复合材料强度高、涡流损耗小、护套厚度也远小于金属护套,具有良好的发展前景。该文通过建立热塑性复合材... 随着舰船综合电力系统对电机转速和功率需求的不断增大,传统非导磁金属材料已难以满足大功率高速永磁电机护套机械强度要求,热塑性复合材料强度高、涡流损耗小、护套厚度也远小于金属护套,具有良好的发展前景。该文通过建立热塑性复合材料(T700/PEEK)激光加热成型过程三维温度-流体-运动多物理场耦合分析模型,考虑热塑性树脂熔化相变过程,提出预浸带截面运动速度+力学载荷边界结合局部圆柱坐标系的方法,解决了大张力载荷预浸带缠绕等效模拟难题,实现了考虑材料非线性的大张力缠绕高速电机转子复合材料护套成型工艺过程的多物理场耦合模拟。通过实验测试的温度与仿真结果对比,验证该文建立的多物理场耦合仿真模型的有效性。该研究所得结论对完善高速永磁电机转子复合材料护套张力缠绕工艺具有一定参考价值。 展开更多
关键词 高速永磁电机 热塑性复合材料 原位成型 张力缠绕 温度场 多物理场耦合
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基于应力响应系数Kw的唐山古冶5.1级地震孕震过程应力场反演
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作者 纪春玲 董博 马广庆 《华北地震科学》 2023年第2期43-50,共8页
通过计算唐山及邻区含水层对应力变化的响应系数K w,结合井水位变化,反演出唐山古冶5.1级地震前后应力场的变化情况,结果表明:①2020年7月唐山区域应力场发生了明显的转折变化,由1.583 Pa的压应力作用变为−2.869 Pa的张应力作用,应力变... 通过计算唐山及邻区含水层对应力变化的响应系数K w,结合井水位变化,反演出唐山古冶5.1级地震前后应力场的变化情况,结果表明:①2020年7月唐山区域应力场发生了明显的转折变化,由1.583 Pa的压应力作用变为−2.869 Pa的张应力作用,应力变化幅度达4.452 Pa;②区域应力场演化的基本特征从时间进程表现为挤压—增强—转折—拉张—减弱—恢复,从空间进程表现为应力集中—增长扩展(西—东方式)—打破活动断层控制,震后转折—减弱转移—恢复,强度演化特征为震源区周围应力场由正常逐渐增强,达到一定程度后增强速率变缓,继而发震,震后较快减弱直至消失;③利用井水位长期变化趋势、井水位孔隙压二年变差、震源机制解和GNSS解算得到的结论与利用含水层对应力变化的响应能力所得区域应力场应力状态一致,整体上呈现近EW向压缩、近NS向拉张的受力状态。 展开更多
关键词 应力场反演 挤压 拉张 结果验证
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10%精草铵膦可溶液剂配方开发及其对非耕地杂草的防除效果评价
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作者 王清 沈兰兰 +3 位作者 姚二艳 黄海燕 陈静 秦龙 《世界农药》 CAS 2023年第10期27-32,40,共7页
为筛选出合格的10%精草铵膦铵盐可溶液剂配方,明确新配方产品对非耕地杂草的除草效果,为其在非耕地杂草防除方面的推广应用提供参考,进行产品配方开发和田间药效试验。通过对润湿剂和渗透剂的筛选,获得10%精草铵膦铵盐可溶液剂最优配方:... 为筛选出合格的10%精草铵膦铵盐可溶液剂配方,明确新配方产品对非耕地杂草的除草效果,为其在非耕地杂草防除方面的推广应用提供参考,进行产品配方开发和田间药效试验。通过对润湿剂和渗透剂的筛选,获得10%精草铵膦铵盐可溶液剂最优配方:48%精草铵膦母液23 g、Wynca 909 15 g、805 1.5 g、水60.5 g。所得制剂外观澄清透明,热储稳定性合格,润湿性能好。10%精草铵膦铵盐可溶液剂对非耕地杂草的防效随着用药量的增加而逐渐提高,药后30 d,使用剂量为300~600 g/hm2时,其对黑麦草、马唐、酢浆草和小飞蓬的株防效分别为81.88%~96.25%、 84.91%~96.70%、 85.71%~99.78%和82.81%~96.88%;鲜重防效分别为82.72%~96.43%、85.68%~96.84%、86.39%~99.82%和83.47%~97.04%。15%Wynca 909+1.5%805可用于配制10%精草铵膦铵盐可溶液剂,制得的产品性能优越,稳定性良好,可用于有效防除非耕地禾本科杂草和阔叶杂草,推荐使用剂量为300~600 g/hm2,兑水600 L/hm2茎叶喷雾使用。 展开更多
关键词 精草铵膦 配方开发 表面张力 接触角 田间药效
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