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Stable Isotope Studies of Crop Carbon and Water Relations:A Review 被引量:5
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作者 ZHANG Cong-zhi ZHANG Jia-bao +2 位作者 ZHAO Bing-zi ZHANG Hui HUANG Ping 《Agricultural Sciences in China》 CSCD 2009年第5期578-590,共13页
Crop carbon and water relations research is important in the studies of water saving agriculture, breeding program, and energy and material cycles in soil plant atmosphere continuum (SPAC). The purpose of this paper... Crop carbon and water relations research is important in the studies of water saving agriculture, breeding program, and energy and material cycles in soil plant atmosphere continuum (SPAC). The purpose of this paper is to review the current state of knowledge on stable isotopes of carbon, oxygen, and hydrogen in the research of crop carbon and water relations, such as carbon isotope discrimination (△^13C) during carbon fixation process by photosynthesis, application of △^13C in crop water use efficiency (WUE) and breeding programs, oxygen isotope enrichment during leaf water transpiration, CO2 fixation by photosynthesis and release by respiration, application of hydrogen isotope composition (619) and oxygen isotope composition (6180) for determination of water source used by a crop, stable isotope coupling Keeling plot for investigating the carbon and water flux in ecosystem, energy and material cycle in SPAC and correlative integrative models on stable isotope. These aspects contain most of the stable isotope researches on crop carbon and water relations which have been widely explored internationally while less referred in China. Based on the reviewed literatures, some needs for future research are suggested. 展开更多
关键词 carbon fixation CROP REVIEW stable isotopes water relations
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Principled Pragmatism: Understanding the EU Position on Economic Relations with China
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作者 Men Jing 《国际问题研究》 CSSCI 北大核心 2018年第3期216-230,共15页
关键词 principled PRAGMATISM he EU POSITION on ECONOMIC relations with China
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A Generalized Statement of Highest-Entropy Principle for Stable Equilibrium and Non-Equilibrium in Many-Particle Systems
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作者 Pierfrancesco Palazzo 《Journal of Modern Physics》 2016年第3期344-357,共14页
Among all statements of Second Law, the existence and uniqueness of stable equilibrium, for each given value of energy content and composition of constituents of any system, have been adopted to define thermodynamic e... Among all statements of Second Law, the existence and uniqueness of stable equilibrium, for each given value of energy content and composition of constituents of any system, have been adopted to define thermodynamic entropy by means of the impossibility of Perpetual Motion Machine of the Second Kind (PMM2) which is a consequence of the Second Law. Equality of temperature, chemical potential and pressure in many-particle systems are proved to be necessary conditions for the stable equilibrium. The proofs assume the stable equilibrium and derive, by means of the Highest-Entropy Principle, equality of temperature, chemical potential and pressure as a consequence. A first novelty of the present research is to demonstrate that equality is also a sufficient condition, in addition to necessity, for stable equilibrium implying that stable equilibrium is a condition also necessary, in addition to sufficiency, for equality of temperature potential and pressure addressed to as generalized potential. The second novelty is that the proof of sufficiency of equality, or necessity of stable equilibrium, is achieved by means of a generalization of entropy property, derived from a generalized definition of exergy, both being state and additive properties accounting for heat, mass and work interactions of the system underpinning the definition of Highest-Generalized-Entropy Principle adopted in the proof. 展开更多
关键词 Many-Particle Systems stable Equilibrium NON-EQUILIBRIUM Second Law Generalized Potential Generalized Reservoir Generalized Exergy Generalized Entropy Highest-Generalized-Entropy principle
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Quantum correlation enhanced bound of the information exclusion principle
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作者 张钧 贺衎 +1 位作者 张昊 于长水 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期137-143,共7页
We investigate the information exclusion principle for multiple measurements with assistance of multiple quantum memories that are well bounded by the upper and lower bounds.The lower bound depends on the observables&... We investigate the information exclusion principle for multiple measurements with assistance of multiple quantum memories that are well bounded by the upper and lower bounds.The lower bound depends on the observables'complementarity and the complementarity of uncertainty whilst the upper bound includes the complementarity of the observables,quantum discord,and quantum condition entropy.In quantum measurement processing,there exists a relationship between the complementarity of uncertainty and the complementarity of information.In addition,based on the information exclusion principle the complementarity of uncertainty and the shareability of quantum discord can exist as an essential factor to enhance the bounds of each other in the presence of quantum memory. 展开更多
关键词 quantum correlation information exclusion principle entropic uncertainty relation
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日常生活批判中的方法论原则与新观念——列斐伏尔《日常生活批判》第二卷研究
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作者 张一兵 《苏州大学学报(哲学社会科学版)》 北大核心 2024年第2期17-26,共10页
在《日常生活批判》第二卷中,列斐伏尔提出在面对当代资本主义日常生活的批判时,除去坚持总体性和异化批判的原则之外,还必须认识到的一个理论前提,即迅速捕捉到可以运用到日常生活批判中的新观念。这些新观念包括:一是对日常生活的分... 在《日常生活批判》第二卷中,列斐伏尔提出在面对当代资本主义日常生活的批判时,除去坚持总体性和异化批判的原则之外,还必须认识到的一个理论前提,即迅速捕捉到可以运用到日常生活批判中的新观念。这些新观念包括:一是对日常生活的分层研究,将会使对资本主义社会日常生活批判本身变得更加精准和深入;二是注意从多维、结构性和模糊性的角度,更加精准地透视日常生活;三是运用社会关系场境论的观点,把握日常生活中社会时间和社会空间的本质;四是超越传统锚定于生产制作活动中的实践概念,科学理解日常生活中的总体实践观念。 展开更多
关键词 列斐伏尔 《日常生活批判》 方法论原则 社会关系场境 总体实践
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基于“浊菀清窍”病机学说论治糖尿病认知功能障碍
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作者 张超 丘宇慧 +1 位作者 章时杰 蔡业峰 《中华中医药学刊》 CAS 北大核心 2024年第1期234-237,共4页
随着糖尿病患病率的不断升高,糖尿病认知功能障碍已成为糖尿病常见的重要并发症之一,并严重影响患者的生活质量,给个人家庭和社会带来沉重的负担。糖尿病认知障碍的现代病理及细胞分子生物学基础是痴呆发病过程中的级联反应,包括但不限... 随着糖尿病患病率的不断升高,糖尿病认知功能障碍已成为糖尿病常见的重要并发症之一,并严重影响患者的生活质量,给个人家庭和社会带来沉重的负担。糖尿病认知障碍的现代病理及细胞分子生物学基础是痴呆发病过程中的级联反应,包括但不限于糖脂代谢异常、β淀粉样蛋白沉积、tau蛋白过度磷酸化、胰岛素抵抗、神经炎症等导致的脑血管和血脑屏障损伤、脑神经元损伤。囿于糖尿病认知障碍目前并无明显有效的诊疗方法,蔡业峰教授基于其创新的“浊菀清窍”疾病病机假说,认为“浊菀清窍”是糖尿病认知功能障碍的病机关键,并揭示了贯穿于糖尿病认知障碍始终的病理实质“浊”和“菀”,并提出“化浊菀,开清窍”为治疗该疾病的核心治疗大法。为糖尿病认知障碍的临床诊治和学术研究提供了新的思路和方法。 展开更多
关键词 浊菀清窍 糖尿病相关认知障碍 病机 治疗
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稳定型心绞痛患者血清核因子E2相关因子2和激活素A表达与冠状动脉侧支循环形成的相关性研究
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作者 郑婉 杨珊珊 +1 位作者 颜亚妮 张园园 《中国心血管病研究》 CAS 2024年第1期79-83,共5页
目的探究稳定型心绞痛患者血清核因子E2相关因子2(NRF2)和激活素A表达与冠状动脉侧支循环形成的相关性。方法收集海南医学院第一附属医院2021年1月到2023年4月期间住院治疗的80例稳定型心绞痛患者,经造影检查冠状动脉为慢性完全闭塞(CTO... 目的探究稳定型心绞痛患者血清核因子E2相关因子2(NRF2)和激活素A表达与冠状动脉侧支循环形成的相关性。方法收集海南医学院第一附属医院2021年1月到2023年4月期间住院治疗的80例稳定型心绞痛患者,经造影检查冠状动脉为慢性完全闭塞(CTO)患者作为研究对象,参照Rentrop分级分为侧支循环形成的不良组(n=34)、良好组(n=46)。采用ELISA法检测血清NRF2与激活素A表达水平,Gensisi评分与患者血清NRF2、激活素A表达水平的关系用Spearman法分析,ROC曲线分析血清NRF2、激活素A水平对患者侧支循环形成不良的预测价值。结果不良组血清NRF2、激活素A表达水平及Gensini评分均显著高于良好组[(2.28±0.42)ng/ml比(1.46±0.37)ng/ml、(583.67±61.25)pg/ml比(472.12±54.26)pg/ml、(45.36±5.81)分比(28.49±4.33)分,t=9.251、8.605、14.889,P<0.05];患者血清NRF2、激活素A表达水平与Gensini评分均呈正相关性(均P<0.05);血清NRF2、激活素A联合预测患者冠状动脉侧支循环形成不良的曲线下面积(AUC)为0.974,优于血清NRF2、激活素A各自单独诊断(Z二者联合-NRF2=2.345、Z二者联合-激活素A=2.639,P=0.019、P=0.008)。结论稳定型心绞痛患者血清NRF2、激活素A表达水平显著升高,且与冠状动脉狭窄严重程度呈正相关性,两者联合对患者冠状动脉侧支循环形成不良具有更高的预测价值。 展开更多
关键词 核因子E2相关因子2 激活素A 稳定型心绞痛 冠状动脉侧支循环 相关性
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接触中国:对华疑惧下尼赫鲁政府对和平共处五项原则的利用(1950—1954)
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作者 刘欣 《边界与海洋研究》 2024年第1期95-109,共15页
随着新中国成立和人民解放军入藏,印度尼赫鲁政府因忧虑其在西藏的特权受到削弱及中国力量迫近印度而对华产生了疑惧心理,决定通过“接触战略”实现对华战略目标。在涉藏问题上,尼赫鲁政府于1950年决定有条件放弃印度在藏特权但坚持印... 随着新中国成立和人民解放军入藏,印度尼赫鲁政府因忧虑其在西藏的特权受到削弱及中国力量迫近印度而对华产生了疑惧心理,决定通过“接触战略”实现对华战略目标。在涉藏问题上,尼赫鲁政府于1950年决定有条件放弃印度在藏特权但坚持印度的边界主张。1954年,尼赫鲁政府主动要求将中方提出的“五项原则”载入《西藏协定》,意图借此作为中国对印度单方面认定边界事实默认的铺垫,从而在和平接触中国中实现其边界主张。为最大程度地发挥“五项原则”中对印有利的因素,印度积极在远东国际政治舞台上推广“五项原则”,追求和缅甸共同构建起“和平约束”中国的联合战线。虽然尼赫鲁政府在对华接触下利用“五项原则”从短期来看取得一定成效,但以表面交好替代不断加强对抗的背后隐含着对华军事防备和挑战。1962年爆发的中印边境战争标志着尼赫鲁政府利用“五项原则”策略的失败,其对华接触外交自此进行了重大调整。 展开更多
关键词 和平共处五项原则 对华接触 中印关系 尼赫鲁
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论《营造法式》开间、柱高的取值比例及其形式关联
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作者 喻梦哲 惠盛健 《建筑史学刊》 2024年第1期121-135,共15页
关于中国古代建筑是否存在复杂精密、成熟稳定且可理性解析的立面构成法则,是建筑历史研究中一个经典的命题。本文在前人研究基础之上,进一步借由作图验算,以铺作层与柱高、间广赋值间的联动方式为考察对象,探索固有数理比例耦合特定图... 关于中国古代建筑是否存在复杂精密、成熟稳定且可理性解析的立面构成法则,是建筑历史研究中一个经典的命题。本文在前人研究基础之上,进一步借由作图验算,以铺作层与柱高、间广赋值间的联动方式为考察对象,探索固有数理比例耦合特定图形关系的内因。提出以分°值控制铺作总高,继而以其作为基准、以檐高的■定出柱高,再由柱高间广关系扩展至整个立面设计的操作模型,并结合《营造法式》料例、功限章节所载数据,验证了该算法的可行性,以期将利用几何或代数方法分别解析宋式建筑立面的两种既有工作统合于同一逻辑框架之内。 展开更多
关键词 立面构成法则 形式关联 数理比例 “白银比”
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DJ-1/Nrf2在精索静脉曲张相关性弱精症生精细胞氧化应激中的表达及意义
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作者 吴元才 蔡佳豆 +2 位作者 唐永泽 罗顺文 李晓伟 《中国计划生育学杂志》 2024年第8期1781-1786,共6页
目的:考察蛋白DJ-1(DJ-1)/稳定核转录因子红系2相关因子2(Nrf2)在精索静脉曲张相关性弱精症患者生精细胞氧化应激中的表达及意义。方法:收集本院2021年12月-2023年12月收治的120例确诊为精索静脉曲张相关性弱精症的男性患者临床资料,60... 目的:考察蛋白DJ-1(DJ-1)/稳定核转录因子红系2相关因子2(Nrf2)在精索静脉曲张相关性弱精症患者生精细胞氧化应激中的表达及意义。方法:收集本院2021年12月-2023年12月收治的120例确诊为精索静脉曲张相关性弱精症的男性患者临床资料,60例为新诊断患者纳入新诊断病例组,60例为接受维生素C联合维生素E治疗3个月的患者纳入病例治疗组;同期婚前健康检查健康男性40例为对照组。检测3组精液生精细胞形态、精液生精细胞的DJ-1、Nrf2蛋白及mRNA,外周血氧化应激[超氧化物歧化酶(SOD)、丙二醛(MDA)、谷胱苷肽过氧化物酶(GSH-Px)]、DJ-1、Nrf2。结果:3组年龄、体质指数、精液体积及精子尾部畸形率均无差异(P>0.05);对照组、病例治疗组、新诊断病例组精子正常形态依次降低,精子头畸形率、体畸形率、头体环合畸形率依次增高,生精细胞DJ-1(0.35±0.11、0.71±0.16、0.89±0.12)、Nrf2蛋白(0.31±0.09、0.62±0.14、0.78±0.13)及mRNA均依次增高,血清MDA、DJ-1、Nrf2依次增高,SOD、GSH-Px依次降低(均P<0.05)。结论:激活DJ-1/Nrf2通路有助于增强精索静脉曲张相关性弱精症生精细胞的抗氧化能力,保护细胞免受由氧化应激引起的损伤,DJ-1/Nrf2通路或是精索静脉曲张相关性弱精症的治疗的潜在分子靶点。 展开更多
关键词 弱精症 精索静脉曲张 生精细胞 蛋白DJ-1 稳定核转录因子红系2相关因子2 氧化应激
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我国涉外信托法律适用的困境及完善路径
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作者 吴雨伦 《太原学院学报(社会科学版)》 2024年第2期30-40,共11页
涉外信托纠纷在国际司法领域频频发生,各国关于涉外信托的法律冲突现象普遍。我国涉外信托冲突法规则具有一定的局限性,无法妥善解决涉外信托存在的法律适用难题。《涉外民事关系法律适用法》第17条的规定主要存在最密切联系原则缺位、... 涉外信托纠纷在国际司法领域频频发生,各国关于涉外信托的法律冲突现象普遍。我国涉外信托冲突法规则具有一定的局限性,无法妥善解决涉外信托存在的法律适用难题。《涉外民事关系法律适用法》第17条的规定主要存在最密切联系原则缺位、意思自治适用范围受限、连接点过少等问题。通过比较分析信托制度应用发达国家的立法、司法实践和《海牙信托公约》,从引入最密切联系原则、延伸意思自治原则适用范围、软化系属公式连接点、建立信托领域案例指导制度以及加强国际法治交流合作等五个方面入手,提出完善涉外信托法律适用的可行性建议。 展开更多
关键词 涉外信托 法律适用 最密切联系原则 连接点软化 案例指导
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意思自治原则在涉外知识产权侵权纠纷法律选择中的适用
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作者 金松 《电子知识产权》 2024年第6期15-26,共12页
意思自治原则应有限适用于涉外知识产权侵权纠纷的法律选择。同时应当对其进行“弱者权利保护”“公共秩序保留”以及“强制性规定”的限制。我国涉外知识产权侵权纠纷的司法实践中,当事人协议选择知识产权侵权准据法的情况极少。在当... 意思自治原则应有限适用于涉外知识产权侵权纠纷的法律选择。同时应当对其进行“弱者权利保护”“公共秩序保留”以及“强制性规定”的限制。我国涉外知识产权侵权纠纷的司法实践中,当事人协议选择知识产权侵权准据法的情况极少。在当事人未选择准据法的情况下,法院的审理存在两方面倾向:一方面,无视知识产权法律冲突,直接适用我国知识产权实体法进行判决;另一方面,适用“被请求保护地法”时直接向“法院地法”逃逸。在现行《涉外民事关系法律适用法》框架下,对被请求保护地在不同情形中应做不同理解:被请求保护地作为知识产权归属和内容的连结点,应理解为权利来源地;作为知识产权侵权责任的连结点,应理解为与案件有最密切联系的侵权行为地。 展开更多
关键词 意思自治原则 涉外知识产权侵权 法律选择 被请求保护地
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台湾问题的国际法解读(上)——台湾问题实质上是中国维护主权和领土完整的问题
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作者 周健 《边界与海洋研究》 2024年第3期3-21,共19页
中国台湾自古以来是中国领土的组成部分。中国在甲午战争后失去台湾地区,在第二次世界大战后恢复对中国台湾的主权。中华人民共和国的建立改变了中国的政治制度,但是没有改变台湾地区作为中国领土组成部分的法律地位。本文基于国际法对... 中国台湾自古以来是中国领土的组成部分。中国在甲午战争后失去台湾地区,在第二次世界大战后恢复对中国台湾的主权。中华人民共和国的建立改变了中国的政治制度,但是没有改变台湾地区作为中国领土组成部分的法律地位。本文基于国际法对台湾问题进行分析,涉及台湾问题的方方面面及其法律上的影响。本文涵盖中国恢复对台湾地区的主权、作为内战结果的海峡两岸政治对立、中国以主权者的名义捍卫对中国台湾的主权、中国在联合国和相关国际组织中的代表权问题,中国同世界各国的建交实践及一中原则的法律含义、中国对台湾地区参与国际活动“空间”的管理等重大问题,并尝试适用国际法做出解读。 展开更多
关键词 中国领土 台湾问题 中国代表权 一中原则 中美关系
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光谱分析技术在环境检测中的相关运用阐述
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作者 袁华芳 《皮革制作与环保科技》 2024年第13期56-58,共3页
随着工业化和城市化进程的加速,环境污染问题日益严重。环境检测在保障人类健康和生态平衡方面发挥着至关重要的作用,然而传统的环境检测方法往往存在效率低下、精度不高等问题,无法满足现代环境监测的需求。因此,寻求一种高效、准确的... 随着工业化和城市化进程的加速,环境污染问题日益严重。环境检测在保障人类健康和生态平衡方面发挥着至关重要的作用,然而传统的环境检测方法往往存在效率低下、精度不高等问题,无法满足现代环境监测的需求。因此,寻求一种高效、准确的环境检测方法成为当务之急。因此,本文通过深入研究分析了光谱分析技术的原理和优势,提出了其在环境检测中的几点有效运用,以期为我国的环境保护提供有力支持。 展开更多
关键词 光谱分析技术 环境检测 基本原理 相关运用
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ENERGY PRINCIPLES IN THEORY OF ELASTIC MATERIALS WITH VOIDS 被引量:4
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作者 罗恩 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1992年第1期44-50,共7页
According to the basic idea of dual-complementarity, in a simple and unified way proposed by the author, various energy principles in theory of elastic materials with voids can be established systematically, In this p... According to the basic idea of dual-complementarity, in a simple and unified way proposed by the author, various energy principles in theory of elastic materials with voids can be established systematically, In this paper, an important integral relation is given, which can be considered essentially as the generalized pr- inciple of virtual work. Based on this relation, it is possible not only to obtain the principle of virtual work and the reciprocal theorem of work in theory of elastic materials with voids, but also to derive systematically the complementary functionals for the eight-field, six-field, four-field and two-field generalized variational principles, and the principle of minimum potential and complementary energies. Furthermore, with this appro ach, the intrinsic relationship among various principles can be explained clearly. 展开更多
关键词 theory of elastic materials with voids variational principle complementary relation mixed problem.
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ON SOME BASIC PRINCIPLES IN DYNAMIC THEORY OF ELASTIC MATERIALS WITH VOIDS 被引量:2
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作者 罗恩 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1993年第2期142-148,共7页
According to the basic idea of dual-complementarity,in a simple and unified way proposed by the author,some basic principles in dynamic theory of elastic materials with voids can be established sys- tematically.In thi... According to the basic idea of dual-complementarity,in a simple and unified way proposed by the author,some basic principles in dynamic theory of elastic materials with voids can be established sys- tematically.In this paper, an important integral relation in terms of convolutions is given,which can be con- sidered as the generalized principle of virtual work in mechanics.Based on this relation,it is possible not on- ly to obtain the principle of virtual work and the reciprocal theorem in dynamic theory of elastic materials with voids,but also to derive systematically the complementary functionals for the eight-field,six-field, four-field and two-field simplified Gurtin-type variational principles.Furthermore,with this approach,the in- trinsic relationship among various principles can be explained clearly. 展开更多
关键词 dynamic theory of elastic materials with voids principle of virtual work reciprocal theorem variational principle complementary relation
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The Fourier Transform and Principles of Quantum Mechanics 被引量:2
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作者 Do Tan Si 《Applied Mathematics》 2018年第4期347-354,共8页
From the hypotheses that the position-representation of a physical state is the Fourier transform of its momentum-representation and that the timerepresentation is the inverse Fourier transform of its energy-represent... From the hypotheses that the position-representation of a physical state is the Fourier transform of its momentum-representation and that the timerepresentation is the inverse Fourier transform of its energy-representation, we are able to obtain the Planck relation E = hν , the de Broglie relation p = h /λ , the Dirac fundamental commutation relation, the Schr?dinger equations, the Heisenberg uncertainty principle in quantum mechanics, and the annihilation/creation of a photon from excitation/de-excitation of an atom following Bohr. 展开更多
关键词 Fourier Transform of BRA Obtaining DIRAC COMMUTATION Relation and principleS of Quantum Mechanics
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A new method for calculating the activity of stable compound from binary phase diagram 被引量:1
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作者 CHEN Dengfu DONG Lingyan BAI Chenguang LIU Qingcai WANG Chuanjun 《Rare Metals》 SCIE EI CAS CSCD 2006年第5期448-451,共4页
A new method to calculate the activity of a stable compound in a binary phase diagram was presented and discussed. According to the formula for calculating activity from the binary phase diagram, the equilibrium const... A new method to calculate the activity of a stable compound in a binary phase diagram was presented and discussed. According to the formula for calculating activity from the binary phase diagram, the equilibrium constant can be calculated through the mass action principle after the activities of two pure components were computed respectively. Based on that, the activity of a stable compound can be easily obtained at last. The activity of the stable compound InSb is calculated in the In-Sb binary system by using this method. The result is well consistent with another calculation value. 展开更多
关键词 physic-chemistry of metallurgy phase diagram mass action principle stable compound activity
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UNCONVENTIONAL HAMILTON-TYPE VARIATIONAL PRINCIPLES FOR DYNAMICS OF REISSNER SANDWICH PLATE 被引量:1
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作者 黄伟江 罗恩 佘慧 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第1期75-82,共8页
According to the basic idea of classical yin-yang complementarity and modern dual-complementarity, in a simple and unified way proposed by Luo(1987), some uncon ventional Hamilton-type variational principles for dyn... According to the basic idea of classical yin-yang complementarity and modern dual-complementarity, in a simple and unified way proposed by Luo(1987), some uncon ventional Hamilton-type variational principles for dynamics of Reissner sandwich plate can be established systematically. The unconventional Hamilton-type variation principle can fully characterize the initial boundary value problem of this dynamics. In this paper, an important integral relation is given, which can be considered as the generalized principle of virtual work in mechanics. Based on this relation, it is possible not only to obtain the principle of virtual work in dynamics of Reissner sandwich plate, but also to derive systematically the complementary functionals for fivefield, two-field and one-field unconventional Hamilton-type variational principles by the generalized Legender transformations. Furthermore, with this approach, the intrinsic relationship among the various principles can be explained clearly. 展开更多
关键词 unconventional Hamilton-type variational principle Reissner sandwich plate DYNAMICS dual-complementary relation initial-boundary-value problem
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Quantitative Expression of Heat Flow versus Tectonic Deformation in the China Continent: The Effects of Plastic-Flow Network and Stable Block 被引量:1
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作者 WANG Sheng-zu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第1期97-109,共13页
Based on the heat flow data published in 1990 and 2001, a study of the factors influencing the terrestrial heat flow distribution in the China continent and its quantitative expression is carried out using the "Netli... Based on the heat flow data published in 1990 and 2001, a study of the factors influencing the terrestrial heat flow distribution in the China continent and its quantitative expression is carried out using the "Netlike Plastic-Flow" continental dynamics model and the methods of statistic analysis and optimum fitting. The result indicates that the factors influencing the heat flow distribution is classified into two groups, i.e. background and tectonic ones, in which the former mainly involves the non- uniform distribution of mantle heat flow, heat production of radioactive dements in the crust, heattransfer media and hydrothermal circulation, while the latter mainly involves plastic-flow networks and relatively-stable blocks. The plastic-flow network is a manifestation of shear localization in the netlike plastic-flow process in the lower lithosphere, which is composed of two sets of plastic-flow belts (PFBs) intersecting each other and, as one of the basic action regimes, controls the intraplate tectonic deformation. Relatively stable blocks (RSBs), which are the tectonic units with relatively-high viscosities existing in the netlike plastic-flow field, as one of the principal origins, result in the development of large-seale compressional basins. PFB and RSB, as the active and quiet states of tectonic deformation, give rise to the higher and lower heat flow values, respectivdy. The provincial average heat flow in continent can be estimated using the expression qav = q0 + a Pbt-c Pbk, where the three terms of the right side are background heat flow, PFB-positive contribution and RSB-negative contribution, Pbt and Pbk are the PFB- and RSB-coverage ratios, respectively, a is the coefficient of PFB- positive contribution depending mainly on the strain in the lower lithosphere, and c is the coefficient of RSB-negative contribution related mainly to the thickness of the lithosphere, the aseismic-area ratio and the tectonic age. For the major portion of the China continent excluding some of the southeastern region of China, the confidence interval of the provincial average background heat flow is qo=57.25±24.8 mW/m^2 and the PFB-positive- and RSB-negative-contribution coefficients are a=14.8-71.9 mW/m^2 and c=0-25.6 mW/m^2, respectively. The concepts of PFB and RSB effects and the heat flow expression suggested provide a new choice of the approach to the quantitative description of the characteristics of heat flow distribution in continent and their physical mechanisms. 展开更多
关键词 continental lithosphere terrestrial heat flow plastic-flow network relatively stable block heat-flow expression
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