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基于OBE理论的案例引导式C语言程序设计实验课程教学改革研究
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作者 刘怡 《实验科学与技术》 2024年第3期94-99,共6页
为了突破C语言程序设计实验教学的难点,基于成果导向教育(OBE)理论对C语言程序设计实验课程进行了教学改革:通过实验教学的模式改革,加强实验教学的结果导向,突出实验教学的学生主体作用,完善实验教学的组织方式;通过引导案例的设计、... 为了突破C语言程序设计实验教学的难点,基于成果导向教育(OBE)理论对C语言程序设计实验课程进行了教学改革:通过实验教学的模式改革,加强实验教学的结果导向,突出实验教学的学生主体作用,完善实验教学的组织方式;通过引导案例的设计、引导案例与实验项目的耦合以及引导案例在实验教学中的应用,实现实验教学方法的改革与实验教学内容的更新。实践结果表明,C语言程序设计实验课程的教学改革,优化了实验课程的教学目标,强化了计算机程序设计类实验课程教学创新的理论基础,提高了实验课程的教学质量。 展开更多
关键词 c语言 OBE理论 实验教学 案例引导
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Comparative study of different theories on active earth pressure 被引量:1
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作者 S.P.Yap F.A.Salman S.M.Shirazi 《Journal of Central South University》 SCIE EI CAS 2012年第10期2933-2939,共7页
Determination of distribution and magnitude of active earth pressure is crucial in retaining wall designs. A number of analytical theories on active earth pressure were presented. Yet, there are limited studies on com... Determination of distribution and magnitude of active earth pressure is crucial in retaining wall designs. A number of analytical theories on active earth pressure were presented. Yet, there are limited studies on comparison between the theories. In this work, comparison between the theories with finite element analysis is done using the PLAXIS software. The comparative results show that in terms of distribution and magnitude of active earth pressure, RANKINE's theory possesses the highest match to the PLAXIS analysis. Parametric studies were also done to study the responses of active earth pressure distribution to varying parameters Increasing soil friction angle and wall friction causes decrease in active earth pressure. In contrast, active earth pressure increases with increasing soil unit weight and height of wall. RANK/NE's theory has the highest compatibility to finite element analysis among all theories, and utilization of this theory leads to proficient retaining wall design. 展开更多
关键词 active earth pressure retaining wall PLAXIS comparative study RANKINE's theory coulomb's theory
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Adapted Metrics for a Modified Coulomb/Newton’s Potential
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作者 Lucian M. Ionescu Cristina-Liliana Pripoae Gabriel Pripoae 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第4期1311-1355,共45页
Modified Theories of Gravity include spin dependence in General Relativity, to account for additional sources of gravity instead of dark matter/energy approach. The spin-spin interaction is already included in the eff... Modified Theories of Gravity include spin dependence in General Relativity, to account for additional sources of gravity instead of dark matter/energy approach. The spin-spin interaction is already included in the effective nuclear force potential, and theoretical considerations and experimental evidence hint to the hypothesis that Gravity originates from such an interaction, under an averaging process over spin directions. This invites to continue the line of theory initiated by Einstein and Cartan, based on tetrads and spin effects modeled by connections with torsion. As a first step in this direction, the article considers a new modified Coulomb/Newton Law accounting for the spin-spin interaction. The physical potential is geometrized through specific affine connections and specific semi-Riemannian metrics, canonically associated to it, acting on a manifold or at the level of its tangent bundle. Freely falling particles in these “toy Universes” are determined, showing an interesting behavior and unexpected patterns. 展开更多
关键词 Modified Gravity Theory SPIN coulomb’s Law Newton’s Law Modified coulomb’s Law Nuclear Force Adapted connection Adapted Metric
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水溶液环境下维生素C与羟基自由基反应的DFT研究
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作者 苏旭发 杨应 +3 位作者 杨清荟 王佐成 姜春旭 张强 《江西师范大学学报(自然科学版)》 CAS 北大核心 2024年第2期147-157,188,共12页
该文采用密度泛函理论(DFT)的M06-2X和MN15方法,结合自洽反应场理论的SMD模型方法,研究了在水液相下维生素C(Vitamin C)分子消除羟自由基的反应机制.研究结果发现:Vitamin C可通过提供给OH氢原子(OH抽H)、与OH加成反应以及单电子从Vitam... 该文采用密度泛函理论(DFT)的M06-2X和MN15方法,结合自洽反应场理论的SMD模型方法,研究了在水液相下维生素C(Vitamin C)分子消除羟自由基的反应机制.研究结果发现:Vitamin C可通过提供给OH氢原子(OH抽H)、与OH加成反应以及单电子从Vitamin C分子向OH自由基转移等3个途径消除OH.势能面计算结果表明:OH抽H的能垒为1.5~55.3 kJ·mol^(-1)(多数分布在1.5~10.8 kJ·mol^(-1)之间),OH加成的能垒为0.0~54.7 kJ·mol^(-1)(多数分布在0.0~0.9 kJ·mol^(-1)之间),电子从Vitamin C向OH转移的能垒为80.9 kJ·mol^(-1).研究结果表明:在水液相下Vitamin C容易与OH反应,Vitamin C是很好的OH自由基清除剂. 展开更多
关键词 维生素c 羟自由基 密度泛函理论 过渡态 电子转移 能垒
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Network Defense Decision-Making Based on Deep Reinforcement Learning and Dynamic Game Theory
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作者 Huang Wanwei Yuan Bo +2 位作者 Wang Sunan Ding Yi Li Yuhua 《China Communications》 SCIE CSCD 2024年第9期262-275,共14页
Existing researches on cyber attackdefense analysis have typically adopted stochastic game theory to model the problem for solutions,but the assumption of complete rationality is used in modeling,ignoring the informat... Existing researches on cyber attackdefense analysis have typically adopted stochastic game theory to model the problem for solutions,but the assumption of complete rationality is used in modeling,ignoring the information opacity in practical attack and defense scenarios,and the model and method lack accuracy.To such problem,we investigate network defense policy methods under finite rationality constraints and propose network defense policy selection algorithm based on deep reinforcement learning.Based on graph theoretical methods,we transform the decision-making problem into a path optimization problem,and use a compression method based on service node to map the network state.On this basis,we improve the A3C algorithm and design the DefenseA3C defense policy selection algorithm with online learning capability.The experimental results show that the model and method proposed in this paper can stably converge to a better network state after training,which is faster and more stable than the original A3C algorithm.Compared with the existing typical approaches,Defense-A3C is verified its advancement. 展开更多
关键词 A3c cyber attack-defense analysis deep reinforcement learning stochastic game theory
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基于第一性原理C-Cd掺杂ZnO的电子结构和光学性质的研究
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作者 张善祥 李海侠 +2 位作者 于镇 吴浩伟 张巍钟 《原子与分子物理学报》 CAS 北大核心 2025年第2期135-142,共8页
借助于计算材料科学和化学的计算机模拟软件Materials Studio,利用密度泛函理论下的第一性原理的计算方法,系统的计算研究了C、Cd单掺杂以及C和Cd共掺杂(不同浓度)ZnO的形成能、电子结构和光学性质.计算结果表明:单掺杂体系当中,C掺杂... 借助于计算材料科学和化学的计算机模拟软件Materials Studio,利用密度泛函理论下的第一性原理的计算方法,系统的计算研究了C、Cd单掺杂以及C和Cd共掺杂(不同浓度)ZnO的形成能、电子结构和光学性质.计算结果表明:单掺杂体系当中,C掺杂时形成能是正的,说明掺杂体系不易形成;共掺杂体系当中,所有掺杂体系的形成能均为负的,C-2Cd掺杂时形成能最低;与本征ZnO相比,所有掺杂体系的禁带宽度均有所降低,由于C元素的掺杂,禁带中产生杂质能级,减小电子跃迁所需要的能量;在光学性质方面,所有掺杂体系在低能区域的吸收图谱、介电函数虚部的峰值与本征ZnO相比均有所增大,且在低能区均发生红移,其中C-2Cd掺杂体系的红移程度最为明显且峰值最大.由此说明C和Cd共掺杂有望提高ZnO的光吸收率和光电转化效率,可以扩展其在光电器件领域中的应用. 展开更多
关键词 c-cd共掺杂 第一性原理 密度泛函理论 电子结构 光学性质
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Facet effects on bimetallic ZnSn hydroxide microcrystals for selective electrochemical CO_(2)reduction
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作者 Liu Han Cheng-wei Wang +3 位作者 Shan-shan Luo Ying-tang Zhou Bing Li Ming Liu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第8期1314-1320,共7页
Employing crystal facets to regulate the catalytic properties in electrocatalytic carbon dioxide reduction reaction(eCO_(2)RR)has been well demonstrated on electrocatalysts containing single metals but rarely explored... Employing crystal facets to regulate the catalytic properties in electrocatalytic carbon dioxide reduction reaction(eCO_(2)RR)has been well demonstrated on electrocatalysts containing single metals but rarely explored for bimetallic systems.Here,we synthesize ZnSn(OH)_(6)(ZSO)microcrystals(MCs)with distinct facets and investigate the facet effects in eCO_(2)RR.Electrochemical studies and in situ Fourier Transform Infrared Spectroscopy(in situ-FTIR)reveal that ZSO MCs produce mainly C1 products of HCOOH and CO.The{111}facet of the ZSO MCS exhibits higher selectivity and faradaic efficiency(FE)than that of the{100}facet over a wide range of potentials(-0.9 V∼-1.3 V versus RHE).Density Functional Theory(DFT)calculations elucidate that the{111}facet is favorable to the adsorption/activation of CO_(2)molecules,the formation of intermediate in the rate-determining step,and the desorption of C1 products of CO and HCOOH molecules. 展开更多
关键词 ZnSn(OH)_(6) crystal facets Electrochemical carbon dioxide reduction c1 product Density functional theory
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Mon(n=2-13)和MonC(n=1-12)团簇的几何结构和电子结构
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作者 杨文辉 相悦 +1 位作者 陈轩 段海明 《原子与分子物理学报》 北大核心 2024年第6期52-59,共8页
结合遗传算法和CALYPSO软件,采用密度泛函理论,对Mon(n=2-13)及MonC(n=1-12)团簇基态的几何结构与电子结构展开详细研究.通过计算其基态结构的平均键长、平均结合能、二阶差分能、分裂能和前线轨道能级,对基态结构的稳定性随总原子数变... 结合遗传算法和CALYPSO软件,采用密度泛函理论,对Mon(n=2-13)及MonC(n=1-12)团簇基态的几何结构与电子结构展开详细研究.通过计算其基态结构的平均键长、平均结合能、二阶差分能、分裂能和前线轨道能级,对基态结构的稳定性随总原子数变化的关系展开了研究.计算结果表明,Mon团簇基态结构的稳定性可通过掺杂单个C原子而提高.综合团簇的二阶差分能、分裂能可知,n=6,9时Mon团簇的稳定性较高,n=4,7,10时MonC团簇的稳定性较高. 展开更多
关键词 密度泛函理论 Mon团簇 Monc团簇 基态结构 电子性质
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Innovative Teaching Research on Literary Theory and Criticism
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作者 HOU Xia 《Sino-US English Teaching》 2024年第7期309-313,共5页
As a core compulsory course for English majors majoring in teacher education,Literary Theory and Criticism plays an important role in enhancing text understanding,cultivating critical thinking,and shaping correct valu... As a core compulsory course for English majors majoring in teacher education,Literary Theory and Criticism plays an important role in enhancing text understanding,cultivating critical thinking,and shaping correct values in the future development of students.Influenced by traditional teaching ideas,students have many difficulties when learning this course,such as insufficient theoretical understanding,inadequate ability improvement,and not enough investment in course learning.In response to the above issues,this course focuses closely on the fundamental task of“cultivating virtue and nurturing people”,relying on modern information technology and introducing research methods of digital humanities.This course uses“7C”teaching mode under the“three-level integration”,in which“teaching”and“education”are carried out synchronously,and“teacher”and“student”are developed together,in order to greatly enhance students’learning participation and course satisfaction. 展开更多
关键词 literary theory and criticism double helix 7c teaching mode three-level integration participation rate satisfaction level
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Si/C复合锂离子电池负极材料的制备及其性能
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作者 孙亚萍 《炼油与化工》 CAS 2024年第5期52-54,共3页
从电池性能的角度出发,合理设计电池负极材料是必要的,为此提出Si/C复合锂离子电池负极材料的制备及电化学性能分析研究。准备实验材料和仪器后,分别按照Si:石墨为1:9、2:8、3:7和4:6的比例准备混合料,按照料液比1:4加入无水乙醇作为球... 从电池性能的角度出发,合理设计电池负极材料是必要的,为此提出Si/C复合锂离子电池负极材料的制备及电化学性能分析研究。准备实验材料和仪器后,分别按照Si:石墨为1:9、2:8、3:7和4:6的比例准备混合料,按照料液比1:4加入无水乙醇作为球磨介质,在球磨机中进行球磨处理,干燥后得到Si含量分别为10%、20%、30%和40%的复合材料;按照质量比为90:5:2:3的比例活性物质(Si/C复合材料)、导电剂碳黑、分散剂乙二醇和粘结剂PVDF配置浆料,涂抹于锂箔表面,经热压成型机对极片进行压实处理,得到Si/C复合锂离子电池负极。在采用电池测试系统在100 mA/g下对硅含量分别为10%、20%、30%和40%的复合材料电极电化学性质进行测试,得出结论Si/C复合锂离子电池负极材料的放电容量受硅含量影响明显,并且不存在直接的线性相关关系;硅含量也会影响Si/C复合锂离子电池负极材料的库伦效率,过高或高低都会导致库伦效率下降。 展开更多
关键词 球磨处理 压实处理 Si/c复合锂离子电池负极 放电容量 库伦效率
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The construction and practice of humanistic care teaching model based on 5C care theory
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作者 Xi-Peng liu Qing-Qing Li +3 位作者 Yu-Zi Zhong Fei-Fei Hong Yan Li Yi-Jing Wang 《Nursing Communications》 2024年第8期1-9,共9页
Objective:To construct a scientific and feasible teaching mode based on 5C caring theory and evaluate it,so as to provide a reference basis for future study about nursing humanistic quality education.Methods:Based on ... Objective:To construct a scientific and feasible teaching mode based on 5C caring theory and evaluate it,so as to provide a reference basis for future study about nursing humanistic quality education.Methods:Based on the 5C caring theory,the teaching design and teaching content were revising and implementing in the intervention group.Before and after the implementation of the course,a questionnaire survey was conducted using the Caring Ability Inventory(CAI).The results of the surveys were collected,and the data were statistically analysis using SPSS.Results:After the implementation of the course,the cognitive dimension,patience dimension,and humanistic caring ability scores of the nursing students in the intervention group improved compared with those before the implementation of the course(P<0.05).There were no significant difference in the control group(P>0.05).Conclusion:The humanistic caring teaching model based on 5C caring theory has a positive effect on improving nursing students'humanistic caring ability.In the future nursing teaching,the modules with the characteristics of humanistic caring ability can be increased,and carry out the educational reform throughout the humanistic caring ability.Actively guiding nursing students to establish the awareness of humanistic caring,so as to lay a solid foundation for high-quality clinical nursing work. 展开更多
关键词 5c caring theory humanistic caring ability undergraduate nursing students teaching model
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C-O型锁扣钢管桩在围堰工程中的实用设计方法
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作者 陈国庆 《铁路工程技术与经济》 2024年第2期35-40,共6页
随着国家对水利投资大幅增长,投融资政策接连落地见效,引水涉水工程逐渐增加,围堰作为涉水工程中重要的阻水结构,其工程应用也日益广泛。锁扣钢管桩通过施加焊锁扣与相邻节点连接,形成排桩围护结构,具有施工快捷、安装效率高、截面强度... 随着国家对水利投资大幅增长,投融资政策接连落地见效,引水涉水工程逐渐增加,围堰作为涉水工程中重要的阻水结构,其工程应用也日益广泛。锁扣钢管桩通过施加焊锁扣与相邻节点连接,形成排桩围护结构,具有施工快捷、安装效率高、截面强度刚度大、可循环利用等优点,在深基坑支护中经常被采用。目前的研究中对锁扣桩挡土结构的力学和技术优势的讨论较少,且缺乏优化设计的方法研究。本文系统总结了不同围堰类型的适用场景和构造施工方法,并以实际围堰工程为例,详细介绍了索塔超大深基坑围堰中的设计方法,旨在优化深水基础钢围堰结构设计,为今后C-O型围堰锁扣钢管桩的设计提供参考。 展开更多
关键词 c-0型 锁扣钢管桩 超大深基坑围堰 方案比选 设计理论
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20世纪岩石强度理论的发展——纪念Mohr-Coulomb强度理论100周年 被引量:92
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作者 俞茂宏 昝月稳 +2 位作者 范文 赵坚 董正筑 《岩石力学与工程学报》 EI CSCD 北大核心 2000年第5期545-550,共6页
190 0年莫尔 (O. Mohr)教授建立了著名的莫尔 -库仑 (Mohr- Coulomb)强度理论。 10 0年来 ,岩石强度理论广泛吸引了工程师和物理学家 (包括工程地质专家、力学家、地球物理学家、材料科学家和土木、机械工程师等 )的注意 ,对岩石在复杂... 190 0年莫尔 (O. Mohr)教授建立了著名的莫尔 -库仑 (Mohr- Coulomb)强度理论。 10 0年来 ,岩石强度理论广泛吸引了工程师和物理学家 (包括工程地质专家、力学家、地球物理学家、材料科学家和土木、机械工程师等 )的注意 ,对岩石在复杂应力状态下的强度理论 (破坏准则 )以及它们的实验验证进行了大量研究 ,提出了众多岩石破坏准则 ,并进行了大量轴对称围压三轴试验和真三轴试验。对 10 0年来的岩石强度理论研究的发展和主要结果进行小结 ,特别是从理论上总结了从强度理论的下限 (莫尔 -库仑单剪强度理论 ,190 0 )到上限 (双剪强度理论 ,俞茂宏 ,1985 )到统一强度理论 (俞茂宏 ,1991)的发展。对 10 0年来岩石强度理论发展的回顾 。 展开更多
关键词 岩石 强度理论 单剪强度理论 双剪强度理论
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Coulomb土压力理论的两种解法 被引量:13
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作者 李兴高 刘维宁 《岩土力学》 EI CAS CSCD 北大核心 2006年第6期981-985,共5页
采用极限平衡变分法和Culmann分析方法,对土压力问题进行了研究。在极限平衡变分法中,以滑动体静力平衡的2个力的平衡方程为基础,引入Lagrange乘子,将以变分学观点来描述的主动土压力和被动土压力问题,转化为确定含有2个函数自变量的泛... 采用极限平衡变分法和Culmann分析方法,对土压力问题进行了研究。在极限平衡变分法中,以滑动体静力平衡的2个力的平衡方程为基础,引入Lagrange乘子,将以变分学观点来描述的主动土压力和被动土压力问题,转化为确定含有2个函数自变量的泛函极值问题。依据泛函取极值时,必须满足Euler方程,得出了主动土压力和被动土压力取极值时墙后土体沿平面滑动破坏的结论。在Culmann分析方法中,沿用了Coulomb土压力理论关于平面滑动破坏的假定,而在推导土压力计算公式的过程中,仅利用了滑动体沿某一特定方向的一个力的平衡方程。与目前通行的Coulomb土压力公式的证明过程相比,Culmann分析方法更为简洁。 展开更多
关键词 coulomb土压力理论 变分学 极限平衡法 culmann分析方法
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形如Coulomb势的本征值微扰计算
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作者 徐永丽 苏新武 《大学物理》 北大核心 2007年第5期29-31,共3页
用超位力定理(HVT)和赫尔曼-费恩曼(Hellman-Feynman)定理(HFT)计算了Coulomb势加上径向线性项和常数项的本征能量的微扰系数,这种计算方法优于通常的瑞利-薛定谔微扰理论,不需要计算本征函数系数,并且用这种方法可以既快捷又有效地计... 用超位力定理(HVT)和赫尔曼-费恩曼(Hellman-Feynman)定理(HFT)计算了Coulomb势加上径向线性项和常数项的本征能量的微扰系数,这种计算方法优于通常的瑞利-薛定谔微扰理论,不需要计算本征函数系数,并且用这种方法可以既快捷又有效地计算大量本征能量的微扰系数. 展开更多
关键词 微扰理论 coulomb 本征能量
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C-E Translation of Public Signs in Xi'an under the Guidance of Skopostheorie
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作者 贾敏 《科技视界》 2014年第23期35-36,共2页
Public signs are widely used in our lives, and increasingly play a significant role with the boom of international tourism. Xi'an, as a major tour destination of China, needs more accurate public signs. Skopostheo... Public signs are widely used in our lives, and increasingly play a significant role with the boom of international tourism. Xi'an, as a major tour destination of China, needs more accurate public signs. Skopostheorie offers a new perspective for translation and translating. In Skopostheorie, translation is seen as translational action with purposes. The TT which doesn't achieve the function and purpose is not an adequate translation. In this thesis, C-E translation of public signs under the guidance of Skopostheorie in Xi'an is discussed. 展开更多
关键词 英语学习 学习方法 阅读知识 阅读材料
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四位一体知信行健康教育模式在儿童^(13)C-尿素呼气试验检测中的应用研究
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作者 龙弦弦 廖婵 林琳 《基层医学论坛》 2023年第21期94-97,共4页
目的探讨四位一体知信行健康教育模式在儿童13C-尿素呼气试验检测中的应用效果。方法选择2021年7月一2022年2月于广西壮族自治区妇幼保健院就诊的300名儿童,以随机数字表法分为2组,各150名,对照组采用常规健康教育指导,试验组采用四位... 目的探讨四位一体知信行健康教育模式在儿童13C-尿素呼气试验检测中的应用效果。方法选择2021年7月一2022年2月于广西壮族自治区妇幼保健院就诊的300名儿童,以随机数字表法分为2组,各150名,对照组采用常规健康教育指导,试验组采用四位一体知信行行为理论健康教育模式指导。对比分析2组^(13)C一尿素呼气试验检测吹气方法的掌握率、依从性、家属满意度。结果试验组的^(13)C一尿素呼气试验检测吹气方法的掌握率、依从性、家属满意度均高于对照组,差异有统计学意义(P<0.05)。结论将四位一体知信行健康教育模式应用于儿童^(13)C一尿素呼气试验检测可有效提高儿童依从率及家长满意度,值得推广。 展开更多
关键词 ^(13)c-尿素呼气试验 健康教育 四位一体 知信行
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Q-Theory: A Connection between Newton’s Law and Coulomb’s Law? 被引量:1
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作者 Christopher Pilot 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第2期632-660,共29页
Assuming a Winterberg model for space where the vacuum consists of a very stiff two-component superfluid made up of positive and negative mass planckions, Q theory is the hypothesis, that Planck charge, <i>q<... Assuming a Winterberg model for space where the vacuum consists of a very stiff two-component superfluid made up of positive and negative mass planckions, Q theory is the hypothesis, that Planck charge, <i>q<sub>pl</sub></i>, was created at the same time as Planck mass. Moreover, the repulsive force that like-mass planckions experience is, in reality, due to the electrostatic force of repulsion between like charges. These forces also give rise to what appears to be a gravitational force of attraction between two like planckions, but this is an illusion. In reality, gravity is electrostatic in origin if our model is correct. We determine the spring constant associated with planckion masses, and find that, <img src="Edit_770c2a48-039c-4cc9-8f66-406c0cfc565c.png" width="90" height="15" alt="" />, where <i>ζ</i>(3) equals Apery’s constant, 1.202 …, and, <i>n</i><sub>+</sub>(0)=<i>n</i>_(0), is the relaxed, <i>i.e.</i>, <img src="Edit_813d5a6f-b79a-49ba-bdf7-5042541b58a0.png" width="25" height="12" alt="" />, number density of the positive and negative mass planckions. In the present epoch, we estimate that, <i>n</i><sub>+</sub>(0) equals, 7.848E54 m<sup>-3</sup>, and the relaxed distance of separation between nearest neighbor positive, or negative, planckion pairs is, <i>l</i><sub>+</sub>(0)=<i>l</i><sub>_</sub>(0)=5.032E-19 meters. These values were determined using box quantization for the positive and negative mass planckions, and considering transitions between energy states, much like as in the hydrogen atom. For the cosmos as a whole, given a net smeared macroscopic gravitational field of, <img src="Edit_efc8003d-5297-4345-adac-4ac95536934d.png" width="80" height="15" alt="" />, due to all the ordinary, and bound, matter contained within the observable universe, an average displacement from equilibrium for the planckion masses is a mere 7.566E-48 meters, within the vacuum made up of these particles. On the surface of the earth, where, <i>g</i>=9.81m/s<sup>2</sup>, the displacement amounts to, 7.824E-38 meters. All of these displacements are due to increased gravitational pressure within the vacuum, which in turn is caused by applied gravitational fields. The gravitational potential is also derived and directly related to gravitational pressure. 展开更多
关键词 Extended Gravity Winterberg Model Planckion Mass Theory Modified Quantum Vacuum Planck charge Newton’s Law coulomb’s Law Dark Energy
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铁卟啉催化氧化邻、对硝基取代芳烃α-C-H键的密度泛函理论研究 被引量:1
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作者 郭静 宋旭锋 +1 位作者 于艳敏 高倩倩 《材料导报》 EI CAS CSCD 北大核心 2023年第8期207-212,共6页
采用密度泛函理论方法对铁卟啉催化氧化邻、对硝基取代芳烃(甲苯、乙苯、异丙苯)α-C-H键的反应进行研究,并将其与无硝基取代芳烃α-C-H键的氧化反应进行比较,重点考察铁卟啉催化氧化邻硝基取代芳烃和对硝基取代芳烃α-C-H键反应活性的... 采用密度泛函理论方法对铁卟啉催化氧化邻、对硝基取代芳烃(甲苯、乙苯、异丙苯)α-C-H键的反应进行研究,并将其与无硝基取代芳烃α-C-H键的氧化反应进行比较,重点考察铁卟啉催化氧化邻硝基取代芳烃和对硝基取代芳烃α-C-H键反应活性的差异,并探究影响反应活性的本质因素。通过计算取代芳烃α-C-H键的键解离能及铁卟啉催化氧化芳烃α-C-H键的反应活化能发现,由于硝基与苯环的共轭效应,对硝基取代芳烃α-C-H键的键解离能减小,铁卟啉高价金属氧化物氧化对硝基取代芳烃α-C-H键反应的活化能较低。邻硝基取代芳烃除共轭效应外还存在空间位阻效应,且空间位阻效应占主导作用。空间位阻效应使得邻硝基取代芳烃α-C-H键的键解离能增大,铁卟啉高价金属氧化物氧化邻硝基取代芳烃α-C-H键反应的活化能较高。对芳烃α-C-H键氧化反应的活化能进一步分析发现,过渡态结构中芳烃与铁卟啉高价金属氧化物之间的相互作用能相对较小,形变能是影响反应活化能的主要因素,且形变能主要来自于芳烃分子的形变。 展开更多
关键词 铁卟啉 催化氧化 芳烃 α-c-H键 密度泛函理论
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Co-seismic Coulomb stress changes on the northern Tanlu fault zone caused by the Tohoku-Oki M_(W)9.0 earthquake 被引量:1
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作者 Fei Chen Tai Liu +2 位作者 Yawen She Xing Huang Guangyu Fu 《Earthquake Science》 2020年第1期11-22,共12页
Based on the spherical earth dislocation theory and a fault slip model of the Tohoku-Oki M_(W)9.0 earthquake,the co-seismic Coulomb failure stress changes(ΔCFS)on the northern Tanlu fault zone at depths of 0–40 km a... Based on the spherical earth dislocation theory and a fault slip model of the Tohoku-Oki M_(W)9.0 earthquake,the co-seismic Coulomb failure stress changes(ΔCFS)on the northern Tanlu fault zone at depths of 0–40 km are calculated.By comparing two sets of results from the spherical earth dislocation theory and the semi-infinite space one,the effect of earth curvature on the calculation results is analyzed quantitatively.First,we systematically summarize previous researches related to the northern Tanlu fault zone,divide the fault zone as detailed as possible,give the geometric parameters of each segment,and establish a segmented structural model of the northern Tanlu fault zone.Second,we calculate the Coulomb stress changes on the northern Tanlu fault zone by using the spherical earth dislocation theory.The result shows the Coulomb stress changes are no more than 0.003 MPa,which proves the great earthquake did not significantly change the stress state of the fault zone.Finally,we quantitatively analyze the disparities between the results of semi-infinite space dislocation theory and the spherical earth one.The average disparity between them is about 7.7%on the northern Tanlu fault zone and is 16.8%on the Fangzheng graben,the maximum disparity on this graben reaches up to 25.5%.It indicates that the effect of earth curvature can not be ignored.So it’s necessary to use the spherical earth dislocation theory instead of the semi-infinite space one to study the Coulomb stress change in the far field. 展开更多
关键词 the northern Tanlu fault zone segmented structural model spherical earth dislocation theory the Tohoku-Oki M_(W)9.0 earthquake co-seismic coulomb stress change(△cFS)
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