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Preparation and Properties of Spray Polyurea Elastomer for Aquaculture Foam Floating Balls
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作者 Guifang HUANG Guanyuan WEI +3 位作者 Shengjun WEI Lan DING Wenhong CAI Bolin PAN 《Agricultural Biotechnology》 2024年第2期38-42,共5页
[Objectives] This study was conducted to develop a polyurea elastomer which can be sprayed on the surface of expanded polystyrene (EPS) floating balls, so as to improve the surface strength and service life of the flo... [Objectives] This study was conducted to develop a polyurea elastomer which can be sprayed on the surface of expanded polystyrene (EPS) floating balls, so as to improve the surface strength and service life of the floating balls. [Methods] The effects of the types and amounts of isocyanate, chain extenders and polyether polyols on the gelation rate, adhesion and wear resistance of polyurea elastomer were investigated, and it was finally determined the preparation process of polyurea elastomer using liquid isophorone diisocyanate (IPDI) and amino-terminated polyether (D2000) as the main raw materials, dimethylthiotoluene diamine (E300) as the chain extender and silica as the wear resistance modifier through two-step solution polymerization of prepolymerization and chain extension. [Results] The physical properties and chemical resistance tests of spray polyurea elastomer showed that it had good physical properties and acid and alkali resistance, and could meet the requirements of spraying and protection of EPS floating ball surface in marine environment. [Conclusions] Polyurea elastomer coating can improve the aging resistance, wear resistance and acid and alkali resistance of EPS floating balls, and prevent them from being fragile and floating randomly to form marine floating garbage which results in "white pollution". 展开更多
关键词 EPS floating ball Spray polyurea elastomer Gelation rate Wear resistant ADHESION Chemical resistance
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Effect of Additional Applied Thermal/Electric Field on the Float-glass Surface 被引量:1
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作者 申祖武 刘启明 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第2期308-311,共4页
The chemical resistances of float-glasses subjected to different electric field strength and temperature were investigated. It is indicated that the chemical resistance increases after the float-glasses are annealed w... The chemical resistances of float-glasses subjected to different electric field strength and temperature were investigated. It is indicated that the chemical resistance increases after the float-glasses are annealed with suitable temperature and electric field strength. It is also observed that the Na+ content varies obviously under the conditions of 570℃, 1500 V/cm and 10 min, implying that the application of thermal/electric field improves the chemical resistance of float-glass online. 展开更多
关键词 float-glass chemical resistance thermal/electric field
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KINETIC FACTORS AFFECTING THE CORROSION OF SiO_2 IN SILICATE GLASSES CAUSED BY ALKALINE SOLUTIONS
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作者 吴正明 步恒祉 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1995年第2期1-10,共10页
The corrosion of a ZrO2 containing alkali re-sistant silicate glass, float glass and silica glass caused by the aqueous solution of NaOH was studied by use of correlation method with spectrophotometry. Effects of the ... The corrosion of a ZrO2 containing alkali re-sistant silicate glass, float glass and silica glass caused by the aqueous solution of NaOH was studied by use of correlation method with spectrophotometry. Effects of the corroding tem-perature, time and solution concentration on the rate of reac-tion and the degree of corrosion were investigated; effects of the apparent activation energy and the experimental value of frequency factor on the rate constant were discussed. 展开更多
关键词 alkali-resistant glass silica glass float glass kinetics of alkaline corrosion
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Mathematical Reasoning of Treatment Principle Based on “Yin Yang Wu Xing” Theory in Traditional Chinese Medicine 被引量:5
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作者 Yingshan Zhang 《Chinese Medicine》 2011年第1期6-15,共10页
By using mathematical reasoning, this paper demonstrates the treatment principle: “Virtual disease is to fill his mother but real disease is to rush down his son” and “Strong inhibition of the same time, support th... By using mathematical reasoning, this paper demonstrates the treatment principle: “Virtual disease is to fill his mother but real disease is to rush down his son” and “Strong inhibition of the same time, support the weak” based on “Yin Yang Wu Xing” Theory in Traditional Chinese Medicine (TCM). We defined two kinds of opposite relations and one kind of equivalence relation, introduced the concept of steady multilateral systems with two non-compatibility relations, and discussed its energy properties. Later based on the treatment of TCM and treated the healthy body as a steady multilateral system, it has been proved that the treatment principle is true. The kernel of this paper is the existence and reasoning of the non-compatibility relations in steady multilateral systems, and it accords with the oriental thinking model. 展开更多
关键词 Traditional Chinese Medicine “Yin Yang WU Xing” theORY steady Multilateral Systems Opposite RELATIONS Side Effects Medical and Drug resistance Problem
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A novel planar vertical double-diffused metal-oxide-semiconductor field-effect transistor with inhomogeneous floating islands 被引量:1
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作者 任敏 李泽宏 +3 位作者 刘小龙 谢加雄 邓光敏 张波 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第12期450-455,460+459,共6页
A novel planar vertical double-diffused metal-oxide-semiconductor (VDMOS) structure with an ultra-low specific on-resistance (Ron,sp), whose distinctive feature is the use of inhomogeneous floating p-islands in th... A novel planar vertical double-diffused metal-oxide-semiconductor (VDMOS) structure with an ultra-low specific on-resistance (Ron,sp), whose distinctive feature is the use of inhomogeneous floating p-islands in the n-drift region, is proposed. The theoretical limit of its Ron,sp is deduced, the influence of structure parameters on the breakdown voltage (BV) and Ron,sp are investigated, and the optimized results with BV of 83 V and Ron,sp of 54 mΩ.mm2 are obtained. Simulations show that the inhomogeneous-floating-islands metal-oxide-semiconductor field-effect transistor (MOSFET) has a superior "Ron,sp/BV" trade-off to the conventional VDMOS (a 38% reduction of Ron,sp with the same BV) and the homogeneous-floating-islands MOSFET (a 10% reduction of Ron,sp with the same BV). The inhomogeneous-floatingislands MOSFET also has a much better body-diode characteristic than the superjunction MOSFET. Its reverse recovery peak current, reverse recovery time and reverse recovery charge are about 50, 80 and 40% of those of the superjunction MOSFET, respectively. 展开更多
关键词 inhomogeneous floating islands specific on-state resistance breakdown voltage body diode reverse recovery
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Mathematical Reasoning of Treatment Principle Based on “Yin Yang Wu Xing” Theory in Traditional Chinese Medicine (II) 被引量:4
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作者 Yingshan Zhang 《Chinese Medicine》 2011年第4期158-170,共13页
By using mathematical reasoning, this paper demonstrates the treatment principle: “Do not treat a disease after it has occurred. But treat the disease before it will occur” (不治已病治未病) based on “Yin Yang Wu X... By using mathematical reasoning, this paper demonstrates the treatment principle: “Do not treat a disease after it has occurred. But treat the disease before it will occur” (不治已病治未病) based on “Yin Yang Wu Xing” Theory in Traditional Chinese Medicine (TCM). We defined generalized relations and reasoning, introduced the concept of generalized steady multilateral systems, and discussed its energy properties. Later based on the treatment of TCM and treated the healthy body as a steady multilateral system, it has been proved that the treatment principle above is true. The kernel of this paper is the existence and reasoning of the non-compatibility relations in steady multilateral systems, and it accords with the oriental thinking model. 展开更多
关键词 Traditional Chinese Medicine (TCM) “Yin Yang WU Xing” theORY steady Multilateral Systems Opposite Relations SIDE-EFFECTS Medical and Drug resistance Problem
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Acupuncture Treating Dystrophy Based on pH <br/>—Mathematical Reasoning of Treatment Principle Based on Yin Yang Wu Xing Theory in Traditional Chinese Medicine (III) 被引量:2
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作者 Yingshan Zhang Bibo Zhang 《Chinese Medicine》 2019年第2期39-105,共67页
Theory of both Zangxiang (藏象) and Jingluo (经络) is useful in understanding disease. By using mathematical reasoning based on Yin Yang Wu Xing Theory in Traditional Chinese Medicine (TCM), this paper demonstrates th... Theory of both Zangxiang (藏象) and Jingluo (经络) is useful in understanding disease. By using mathematical reasoning based on Yin Yang Wu Xing Theory in Traditional Chinese Medicine (TCM), this paper demonstrates the treatment principle: “Searching for a root cause of disease in cure, treatment of both the root-cause and symptoms at the same time” (治病求本, 标本兼治). It means that for a human body, there is the mathematical structure of both Zangxiang and Jingluo as her/his second physiological system. It can be used to determine both the root-cause and symptoms of the sick organ by using both Zangxiang and Jingluo. In general, for the human blood pH value, the normal range of theory is [7.34539, 7.45461] nearly to [7.35, 7.45], and the center is 7.4. The first or second transfer law of a human body’s energies changes according to the different blood pH values whether in the normal range or not. Human disease treatment should protect and maintain the balance of two incompatibility relations: the loving relationship and the killing relationship. As an application, acupuncture is used to treat limb-girdle muscular dystrophy. 展开更多
关键词 Traditional Chinese Medicine (TCM) YIN Yang WU Xing theORY steady Multilateral Systems INCOMPATIBILITY Relations Side Effects Medical and Drug resistance Problem
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Acupuncture Treating Heart Disease Based on Eight Palaces or Eight Veins <br/>—Mathematical Reasoning of Treatment Principle Based on Yin Yang Wu Xing Theory in Traditional Chinese Medicine (IV) 被引量:1
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作者 Yingshan Zhang Yan Li Chunyun Guo 《Chinese Medicine》 2021年第3期47-117,共71页
Theory<span><span><span style="font-family:;" "=""> of eight palaces (</span></span></span><span><span><span style="font-family:宋体;&qu... Theory<span><span><span style="font-family:;" "=""> of eight palaces (</span></span></span><span><span><span style="font-family:宋体;">八宫</span></span></span><span><span><span style="font-family:;" "="">) or eight veins (</span></span></span><span><span><span style="font-family:宋体;">八脉</span></span></span><span><span><span style="font-family:;" "="">) is useful in understanding the basic sick subsystems that may be to fall ills as the <span>root-cause</span>. By using mathematical reasoning based on Yin Yang Wu Xing Theory in Traditional Chinese Medicine (TCM), this paper demonstrates the treatment principle: “Even if all changed, it is hard to change one’s nature” (</span></span></span><span><span><span style="font-family:宋体;">江山易改</span></span></span><span><span><span style="font-family:;" "="">, </span></span></span><span><span><span style="font-family:宋体;">本性难移</span></span></span><span><span><span style="font-family:;" "="">). The eight palaces or eight veins can be used to diagnose basic sick subsystems that may be to fall ills as the <span>root-cause</span>. The first or second transfer law of human body energies of the eight palaces or eight veins according to the different blood pH values of a human body whether in the normal range or not,</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">respectively,</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">assuming</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">that the range of blood pH value is divided into four parts from small to large. Both second and third are for a healthy human body. Both the <span>root-cause</span> and symptoms come from the first transfer law of human body energies. And both first and fourth are for an unhealthy human body. Both the <span>root-cause</span> and symptoms come from the second transfer law of human body energies. A disease treatment should protect and maintain the balance of two incompatibility relations: the loving relationship and the killing relationship. As an application, acupuncture is used to treat atrial premature beats as <span>a congenital</span> heart disease.</span></span></span> 展开更多
关键词 Traditional Chinese Medicine (TCM) Yin Yang Wu Xing theory steady Multilateral Systems Incompatibility Relations Side Effects Medical and Drug resistance Problem
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Mathematical Reasoning of Treatment Principle Based on the Stable Logic Analysis Model of Complex Systems
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作者 Yingshan Zhang 《Intelligent Control and Automation》 2012年第1期1-15,共15页
The article reviews the stable logic analysis model of complex systems or steady multilateral systems with two non-compatibility relations. Energy concept in Physics is introduced to the multilateral systems and used ... The article reviews the stable logic analysis model of complex systems or steady multilateral systems with two non-compatibility relations. Energy concept in Physics is introduced to the multilateral systems and used to deal with the multilateral system diseases. By using mathematical reasoning, it is demonstrated that the treatment principle: “Virtual disease is to fill his mother but real disease is to rush down his son” and “Strong inhibition of the same time, support the weak” which due to the “Yin Yang Wu Xing” Theory in Traditional Chinese Medicine (TCM). 展开更多
关键词 steady Multilateral Systems Opposite RELATIONS CAPABILITY of INTERVENTION Reaction CAPABILITY of SELF-PROTECTION Side Effects Medical and Drug resistance Problem
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Acupuncture Treating Heart Diseases Based on Sixty JiaZi and Eight Palaces <br/>—Mathematical Reasoning of Treatment Principle Based on Yin Yang Wu Xing Theory in Traditional Chinese Medicine (V)
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作者 Yingshan Zhang Yan Li Chunyun Guo 《Chinese Medicine》 2021年第3期118-184,共67页
<span style="font-family:Verdana;">Theory</span><span style="font-family:Verdana;" "=""> of Sixty JiaZi (60 </span><span style="font-family:Verdana;&q... <span style="font-family:Verdana;">Theory</span><span style="font-family:Verdana;" "=""> of Sixty JiaZi (60 </span><span style="font-family:Verdana;">甲子</span><span style="font-family:;" "=""><span style="font-family:Verdana;">) is useful in understanding a human body disease. By using mathematical reasoning based on Yin Yang Wu Xing Theory in Traditional Chinese Medicine (TCM), this paper demonstrates the treatment principle: “seize the momentum of development, hasten </span><span style="font-family:Verdana;">lucky</span> <span style="font-family:Verdana;">avoids</span><span style="font-family:Verdana;"> disaster” (</span></span><span style="font-family:Verdana;">顺势而为</span><span style="font-family:Verdana;" "="">, </span><span style="font-family:Verdana;">趋吉避凶</span><span style="font-family:;" "=""><span style="font-family:Verdana;">). Sixty </span><span style="font-family:Verdana;">JiaZi</span><span style="font-family:Verdana;"> is hidden behind eight palaces. The first or second transfer law of human body energies of Sixty JiaZi changes according to the different blood pH values of a human body whether in the normal range or not, respectively, assuming that the range of blood pH values of a human </span><span style="font-family:Verdana;">body</span><span style="font-family:Verdana;"> is divided into four parts from small to large. Both second and third are for a healthy human body. Both the </span><span style="font-family:Verdana;">root-cause</span><span style="font-family:Verdana;"> and symptoms come from the first transfer law of human body energies. And both first and fourth are for an unhealthy human body. Both the </span><span style="font-family:Verdana;">root-cause</span><span style="font-family:Verdana;"> and symptoms come from the second transfer law of human body energies. The treating disease of a human body should protect and maintain the balance of two incompatibility relations: the loving relationship and the killing relationship. As an application, acupuncture is used to treat atrial premature beats as congenital heart disease.</span></span> 展开更多
关键词 Traditional Chinese Medicine (TCM) Yin Yang Wu Xing theory steady Multilateral Systems Incompatibility Relations Side Effects Medical and Drug resistance Problem
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Numerical Study on Heat Transfer Characteristics of Heated/Cooled Rods Having a Composite Board in between: Effect of Thermal Vias
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作者 Yasushi Koito Toshio Tomimura 《Journal of Electronics Cooling and Thermal Control》 2017年第4期91-102,共12页
By placing a sample between a heated and a cooled rod, a thermal conductivity of the sample can be evaluated easily with the assumption of a one-dimensional heat flow. However, a three-dimensional constriction/spreadi... By placing a sample between a heated and a cooled rod, a thermal conductivity of the sample can be evaluated easily with the assumption of a one-dimensional heat flow. However, a three-dimensional constriction/spreading heat flow may occur inside the rods when the sample is a composite having different thermal conductivities. In order to investigate the thermal resistance due to the constriction/spreading heat flow, the three-dimensional numerical analyses were conducted on the heat transfer characteristics of the rods. In the present analyses, a polymer-based composite board having thermal vias was sandwiched between the rods. From the numerical results, it was confirmed that the constriction/spreading resistance of the rods was strongly affected by the thermal conductivity of the rods as well as the number and size of the thermal vias. A simple equation was also proposed to evaluate the constriction/spreading resistance of the rods. Fairly good agreements were obtained between the numerical results and the calculated ones by the simple equation. Moreover, the discussion was also made on an effective thermal conductivity of the composite board evaluated with the heated and the cooled rod. 展开更多
关键词 Heat Transfer Enhancement theRMAL Via Constriction/Spreading resistance steady-STATE Method Effective theRMAL Conductivity
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某上浮地下车库结构检测及加固处理方案
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作者 张学智 霍喆赟 王颖贺 《建筑结构》 北大核心 2024年第10期112-117,共6页
某在建地下车库发生上浮事故,结构上拱现象严重,结构构件出现不同程度的损伤。事故发生后对该工程及时采取了临时应急措施。通过详尽的结构检测,精准定位了地下车库的上浮影响范围,全面掌握了受影响构件的损伤情况。根据检测结果,结合... 某在建地下车库发生上浮事故,结构上拱现象严重,结构构件出现不同程度的损伤。事故发生后对该工程及时采取了临时应急措施。通过详尽的结构检测,精准定位了地下车库的上浮影响范围,全面掌握了受影响构件的损伤情况。根据检测结果,结合原始设计资料和现场实际施工状况,分析了地下车库上浮的主要因素及构件损伤的机理。对上浮影响区域的结构采取了注浆、补桩、构件置换等针对性的加固措施。本工程处理后取得了良好的效果,可为其他类似工程提供参考。 展开更多
关键词 地下车库 抗浮 结构上拱 结构检测 承载力 结构加固
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环形月池对海洋核能平台拖航阻力的影响
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作者 许建龙 刘已华 +1 位作者 李红霞 黄一 《舰船科学技术》 北大核心 2024年第5期59-64,共6页
海洋核能平台2~3年需要拖航至港口进行换料,在其设计的初始阶段对平台拖航阻力的研究至关重要。考虑2种海洋核能平台概念,分析环形月池对平台拖航阻力的影响。采用STAR-CCM+软件对分离式海洋核能平台和一体式海洋核能平台在不同拖航速... 海洋核能平台2~3年需要拖航至港口进行换料,在其设计的初始阶段对平台拖航阻力的研究至关重要。考虑2种海洋核能平台概念,分析环形月池对平台拖航阻力的影响。采用STAR-CCM+软件对分离式海洋核能平台和一体式海洋核能平台在不同拖航速度时的拖航阻力进行计算。结果表明,随着拖航速度的增大,拖航阻力增加明显;月池的存在使平台周围流场趋于紊乱,导致核能平台拖航阻力增加;对月池增阻机理的分析可为核能平台的设计提供参考。 展开更多
关键词 拖航阻力 环形月池 计算流体动力学 浮式核电平台
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漂浮式光伏关键部件耐候性研究综述
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作者 彭煌 王俊 +2 位作者 陈心欣 时宇 王梁彬 《环境技术》 2024年第1期47-53,共7页
为了解决能源需求和环境保护的压力,漂浮式水面光伏被提出作为解决方案。近海海域具有广阔的空间,提供了充足的布设场所,因此海上漂浮式光伏成为研究的热点。评估光伏关键部件的耐候性对确保近海漂浮式光伏系统的可靠性和持久性至关重... 为了解决能源需求和环境保护的压力,漂浮式水面光伏被提出作为解决方案。近海海域具有广阔的空间,提供了充足的布设场所,因此海上漂浮式光伏成为研究的热点。评估光伏关键部件的耐候性对确保近海漂浮式光伏系统的可靠性和持久性至关重要。近年来已出现了一些试验性水上光伏发电项目,显示出漂浮式光伏系统在水域中的潜力。然而,近海环境的湿度、海风、盐雾等因素对光伏关键部件的性能和寿命产生不利影响,因此评估光伏关键部件的耐候性能尤为重要。目前关于水上光伏的研究内容还较为有限,但各国已开始推动该技术的研究和应用。这些研究成果有助于促进近海漂浮式光伏的可持续发展,推进清洁能源的应用和环境保护。 展开更多
关键词 新能源 漂浮式光伏 耐候性 光伏关键部件 可持续发展
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基于导体温升原理的隔离开关发热改善方法研究
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作者 张斌 李健 +2 位作者 鞠恒才 毕胜洁 李峰 《黑龙江科学》 2024年第4期54-57,共4页
隔离开关发热一直是电力系统中难以解决的问题,当隔离开关温度较高时会使零部件温度升高,材料的物理、机械及电气性能逐渐下降,令材料老化速度加快,导致隔离开关出现工作故障,引发停电事故。为解决上述问题,分析了稳态热力系统的构成,... 隔离开关发热一直是电力系统中难以解决的问题,当隔离开关温度较高时会使零部件温度升高,材料的物理、机械及电气性能逐渐下降,令材料老化速度加快,导致隔离开关出现工作故障,引发停电事故。为解决上述问题,分析了稳态热力系统的构成,推导隔离开关温升计算公式,结合接触电阻理论提出隔离开关发热改善方法,采用接触电阻等效并联方式,将接触电阻数值减小,从而提高隔离开关触头系统的通流能力,达到降低温升的目的,以4000 A钳夹式隔离开关为研究对象,进行了实例计算与验证,为实际工程解决隔离开关发热问题提供一定的参考。 展开更多
关键词 隔离开关 稳态热力系统 温升原理 接触电阻
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海洋环境下漂浮光伏电站浮体HDPE材料的抗疲劳性能与优化策略
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作者 周程晟 《合成材料老化与应用》 CAS 2024年第2期71-75,共5页
研究旨在深入探讨高密度聚乙烯(HDPE)材料在海洋环境下应用于漂浮光伏电站浮体的抗疲劳性能。通过试验研究、理论分析和案例研究,探讨了海洋环境因素对漂浮光伏电站浮体HDPE材料疲劳性能的影响,并提出了改进策略。研究发现,在海洋环境中... 研究旨在深入探讨高密度聚乙烯(HDPE)材料在海洋环境下应用于漂浮光伏电站浮体的抗疲劳性能。通过试验研究、理论分析和案例研究,探讨了海洋环境因素对漂浮光伏电站浮体HDPE材料疲劳性能的影响,并提出了改进策略。研究发现,在海洋环境中,改良的HDPE材料在漂浮光伏浮体中表现出优越的抗疲劳特性。使用高效的光屏蔽剂、光吸收助剂和合金混合物作为物理保护,同时使用持久的高低温抗氧化剂、聚合物抗紫外线稳定剂、抗疲劳剂和紫外线活化增韧系统,可以增强HDPE材料的抗老化和加工性能。改良的HDPE材料在海洋环境中的漂浮光伏电站浮体的耐久性和稳定性得到了提升。 展开更多
关键词 海洋环境 漂浮光伏电站 HDPE材料 抗疲劳性能
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Image Mathematics—Mathematical Intervening Principle Based on “Yin Yang Wu Xing” Theory in Traditional Chinese Mathematics (I) 被引量:28
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作者 Yingshan Zhang Weilan Shao 《Applied Mathematics》 2012年第6期617-636,共20页
By using mathematical reasoning, this paper demonstrates the mathematical intervening principle: “Virtual disease is to fill his mother but real disease is to rush down his son” (虚则补其母, 实则泄其子) and “Strong... By using mathematical reasoning, this paper demonstrates the mathematical intervening principle: “Virtual disease is to fill his mother but real disease is to rush down his son” (虚则补其母, 实则泄其子) and “Strong inhibition of the same time, support the weak” (抑强扶弱) based on “Yin Yang Wu Xing” Theory in image mathematics of Traditional Chinese Mathematics (TCMath). We defined generalized relations and generalized reasoning, introduced the concept of steady multilateral systems with two non-compatibility relations, and discussed its energy properties. Later based on the intervention principle in image mathematics of TCMath and treated the research object of the image mathematics as a steady multilateral system, it has been proved that the mathematical intervening principle is true. The kernel of this paper is the existence and reasoning of the non-compatibility relations in steady multilateral systems, and it accords with the oriental thinking model. 展开更多
关键词 Image MAtheMATICS “Yin Yang WU Xing” theory steady Multilateral Systems Opposite Non-Compatibility Relations INTERVENTION RULE Self-Protection RULE MAtheMATICAL Side Effects Mathe-matical INTERVENTION resistance Problem
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Analytical investigation of bidirectional ductile diaphragms in multi-span bridges
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作者 Xiaone Wei Michel Bruneau 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2018年第2期235-250,共16页
In the AASHTO Guide Specifications for Seismic Bridge Design Provisions,ductile diaphragms are identified as Permissible Earthquake-Resisting Elements(EREs),designed to help resist seismic loads applied in the trans... In the AASHTO Guide Specifications for Seismic Bridge Design Provisions,ductile diaphragms are identified as Permissible Earthquake-Resisting Elements(EREs),designed to help resist seismic loads applied in the transverse direction of bridges.When adding longitudinal ductile diaphragms,a bidirectional ductile diaphragm system is created that can address seismic excitations acting along both the bridge’s longitudinal and transverse axes.This paper investigates bidirectional ductile diaphragms with Buckling Restrained Braces(BRBs)in straight multi-span bridge with simply supported floating spans.The flexibility of the substructures in the transverse and longitudinal direction of the bridge is considered.Design procedures for the bidirectional ductile diaphragms are first proposed.An analytical model of the example bridge with bidirectional ductile diaphragms,designed based on the proposed methodology,is then built in SAP2000.Pushover and nonlinear time history analyses are performed on the bridge model,and corresponding results are presented.The effect of changing the longitudinal stiffness of the bidirectional ductile diaphragms in the end spans connecting to the abutment is also investigated,in order to better understand the impact on the bridge’s dynamic performance. 展开更多
关键词 bidirectional ductile diaphragm seismic resistance multi-span bridge with floating spans
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Study and Application of Horizontal Well Productivity Formula with Continuous Time-Varying Considered 被引量:1
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作者 Chao Liu Junting Zhang +2 位作者 Haojun Wu Bo Zhang Long Wang 《Journal of Power and Energy Engineering》 2018年第9期32-39,共8页
The horizontal well technology has been widely applied to enhanced oil recovery for low permeability and heavy oil reservoir. It is the important basis for designing and optimizing horizontal well to determine the pro... The horizontal well technology has been widely applied to enhanced oil recovery for low permeability and heavy oil reservoir. It is the important basis for designing and optimizing horizontal well to determine the productivity. The productivity determination of horizontal wells in offshore oil fields is mainly based on the actual productivity data of producing directional wells in the similar reservoirs nearby. Considering pressure drop and oil layer thickness to calculate the productivity, this method lacks certain theoretical basis and requires rich working experience for reservoir engineers. The other method is Joshi Formula which needs the known horizontal well control radius to be known. But the control radius is man-made at certain degree. In order to address the shortcomings of existing methods, a new reservoir engineering method was proposed to determine the horizontal well productivity formula, horizontal flow pattern and control radius based on the principle of equivalent flow resistance and conformal transformation. This method has overcome the disadvantage of determining on person. It provided some theoretical basis for getting the horizontal well productivity and is of some guiding meaning for evaluating the productivity of adjustment wells and development wells. 展开更多
关键词 Horizontal Well Principle of EQUIVALENT Flow resistance CONFORMAL Transformation Control RADIUS Pseudo-steady State Time
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基于CFD的两栖式清淤机器人水动力特性研究
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作者 芮宏斌 郑文哲 +1 位作者 李路路 曹伟 《应用力学学报》 CAS CSCD 北大核心 2023年第6期1412-1420,共9页
针对某两栖式清淤机器人,基于计算流体力学(computationalfluid dynamics,CFD)分析其静浮态和航行阻力。采用重叠网格方法计算静浮态下的吃水深度和纵倾角;分别采用静态网格方法和重叠网格方法预测两栖式清淤机器人静水直航工况的航行阻... 针对某两栖式清淤机器人,基于计算流体力学(computationalfluid dynamics,CFD)分析其静浮态和航行阻力。采用重叠网格方法计算静浮态下的吃水深度和纵倾角;分别采用静态网格方法和重叠网格方法预测两栖式清淤机器人静水直航工况的航行阻力,并对这两种方法进行对比。研究结果表明:采用重叠网格的方法可以有效计算两栖式清淤机器人静浮态下的吃水深度和纵倾角;静态网格方法和重叠网格方法均能有效预测两栖式清淤机器人水上航行阻力,静态网格方法计算效率高,但仅适用于航速较低的工况,而重叠网格方法适用于不同航速下的航行阻力预测,但计算效率较低。研究结果对两栖式清淤机器人的设计及改进有较大参考价值。 展开更多
关键词 两栖式清淤机器人 计算流体力学 重叠网格 静浮态 航行阻力
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