期刊文献+
共找到3,992篇文章
< 1 2 200 >
每页显示 20 50 100
Solving the Olbers’s Paradox, Explaining the “Red-Shift”, and Challenging the Relativities by “Sun Matters Theory” and “Sun Model of Universe”, an Evolution of the Einstein’s Static Universe Model
1
作者 Wanpeng Sun 《Natural Science》 2024年第2期7-18,共12页
Olbers’s paradox, known as the dark night paradox, is an argument in astrophysics that the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe. Big-Bang theory was used ... Olbers’s paradox, known as the dark night paradox, is an argument in astrophysics that the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe. Big-Bang theory was used to partially explain this paradox, while introducing new problems. Hereby, we propose a better theory, named Sun Matters Theory, to explain this paradox. Moreover, this unique theory supports and extended the Einstein’s static universe model proposed by Albert Einstein in 1917. Further, we proposed our new universe model, “Sun Model of Universe”. Based on the new model and novel theory, we generated innovative field equation by upgrading Einstein’s Field Equation through adding back the cosmological constant, introducing a new variable and modifying the gravitationally-related concepts. According to the Sun Model of Universe, the dark matter and dark energy comprise the so-called “Sun Matters”. The observed phenomenon like the red shift is explained as due to the interaction of ordinary light with Sun Matters leading to its energy and frequency decrease. In Sun Model, our big universe consists of many universes with ordinary matter at the core mixed and surrounded with the Sun Matters. In those universes, the laws of physics may be completely or partially different from that of our ordinary universe with parallel civilizations. The darkness of night can be easily explained as resulting from the interaction of light with the Sun Matters leading to the sharp decrease in the light intensity. Sun Matters also scatter the light from a star, which makes it shining as observed by Hubble. Further, there is a kind of Sun Matters named “Sun Waters”, surrounding every starts. When lights pass by the sun, the Sun Waters deflect the lights to bend the light path. According to the Sun Model, it is the light bent not the space bent that was proposed in the theory of relativities. 展开更多
关键词 Olbers’s Paradox sun Matters theory sun Model of Universe Einstein’s Universe Dark Mass
下载PDF
On a Fractal Version of Witten’s M-Theory 被引量:12
2
作者 Mohamed S. El Naschie 《International Journal of Astronomy and Astrophysics》 2016年第2期135-144,共10页
Starting from Witten’s eleven dimensional M-theory, the present work develops in an analogous way a corresponding dimensional fractal version where . Subsequently, the new fractal formalism is utilized to determine t... Starting from Witten’s eleven dimensional M-theory, the present work develops in an analogous way a corresponding dimensional fractal version where . Subsequently, the new fractal formalism is utilized to determine the measured ordinary energy density of the cosmos which turns out to be intimately linked to the new theory’s fractal dimension via non-integer irrational Lorentzian-like factor: where is Hardy’s probability of quantum entanglement. Consequently, the energy density is found from a limiting classical kinetic energy to be Here, is ‘tHooft’s renormalon of dimensional regularization. The immediate logical, mathematical and physical implication of this result is that the dark energy density of the cosmos must be in astounding agreement with cosmic measurements and observations. 展开更多
关键词 M-theory E-Infinity theory Hardy’s Quantum Entanglement Transfinite Turing Computer Dark Energy Accelerated Cosmic Expansion Noncommutative Geometry superstring theory scale Relativity Cantorian-Fractal spacetime witten’s theory ‘tHooft Renormalon Pure Gravity Penrose Tiling
下载PDF
D-S证据理论在空中目标识别中的应用现状与展望
3
作者 余付平 黄益恒 +2 位作者 沈堤 李靖宇 房瑞跃 《电光与控制》 CSCD 北大核心 2024年第4期75-86,共12页
D-S证据理论作为一种多源信息融合工具,在空中目标识别领域中得到了广泛应用。对D-S证据理论进行了概述;简要梳理了D-S证据理论在空中目标识别领域中的发展脉络,并提出应用中需要解决的三类关键问题;围绕上述问题,重点对该领域中的BPA... D-S证据理论作为一种多源信息融合工具,在空中目标识别领域中得到了广泛应用。对D-S证据理论进行了概述;简要梳理了D-S证据理论在空中目标识别领域中的发展脉络,并提出应用中需要解决的三类关键问题;围绕上述问题,重点对该领域中的BPA获取、证据冲突度量、证据融合的应用现状进行综述;最后,基于空域控制视角,对D-S证据理论在该领域中的应用进行了展望。研究可为空中目标识别领域的理论发展和工程应用提供参考。 展开更多
关键词 空中目标识别 D-s证据理论 BPA 证据冲突 证据融合
下载PDF
基于D-S证据理论的岩爆预测方法研究
4
作者 高永涛 朱强 +1 位作者 吴顺川 王勇兵 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第2期244-251,共8页
为了有效预测岩爆,提出基于D-S证据理论的岩爆预测方法.首先,选取与岩爆发生相关的6个指标因素作为证据体,并通过模糊物元框架和正态型隶属度函数构建证据体的基本概率分配.然后,利用K均值将证据体分类,并提出簇内证据用传统方式融合而... 为了有效预测岩爆,提出基于D-S证据理论的岩爆预测方法.首先,选取与岩爆发生相关的6个指标因素作为证据体,并通过模糊物元框架和正态型隶属度函数构建证据体的基本概率分配.然后,利用K均值将证据体分类,并提出簇内证据用传统方式融合而簇间证据用权重方式融合的组合融合规则,以减轻高冲突证据融合的不利影响.最后,将模型应用在秦岭终南山公路隧道2号竖井工程,且与经验方法对比.为了分析预测过程的不确定性和估计岩爆发生概率,采用蒙特卡洛模拟进行抽样仿真,并通过Spearman秩相关系数衡量输入指标的全局敏感性.研究结果表明:输入指标在不同的岩爆案例的影响程度差异较大且方向不同;5个岩爆案例的发生概率在40.8%~70.1%之间.该模型表现出优异的预测分类性能,可为深埋地下工程岩爆预测提供参考. 展开更多
关键词 岩石力学 岩爆预测 D-s证据理论 模糊物元 K均值
下载PDF
D-S理论和Markov链组合的桥梁性能退化预测研究
5
作者 杨国俊 田里 +2 位作者 唐光武 毛建博 杜永峰 《应用数学和力学》 CSCD 北大核心 2024年第4期416-428,共13页
为准确预测桥梁性能退化,考虑到数据随机性和微小扰动发生状态跳跃,提出了一种D-S(Dempster-Shafer)证据理论和Markov链组合的桥梁性能退化组合预测模型和性能退化率的概念.该模型基于指数平滑(exponential smoothing,ES)方法获得新的... 为准确预测桥梁性能退化,考虑到数据随机性和微小扰动发生状态跳跃,提出了一种D-S(Dempster-Shafer)证据理论和Markov链组合的桥梁性能退化组合预测模型和性能退化率的概念.该模型基于指数平滑(exponential smoothing,ES)方法获得新的预测数据序列,并利用Markov链和D-S理论不断进行优化,从而实现桥梁性能退化的组合预测.实际工程的应用结果表明:性能退化率可以直观地表征在梁性能退化的速度.其次,该模型的平均相对误差为1.54%,较于回归、灰色和模糊加权Markov链模型,精度分别提高了1.11%,0.88%和2.8%,而后验差比值为0.242,小于0.35;模型的标准差为9.021,相比其他模型分别减小了3.978,3.405和7.500,而变异系数为0.109,均小于其他模型,验证了组合预测模型在精度和稳定性方面的优越性,可为在役桥梁结构性能退化预测与维护提供理论基础. 展开更多
关键词 桥梁工程 性能退化预测 D-s证据理论 MARKOV链 组合预测模型 桥梁性能退化率
下载PDF
基于加权D-S证据理论的旋翼故障诊断
6
作者 高亚东 张传壮 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第1期66-75,共10页
旋翼作为直升机的升力面和操作面,其健康状态对直升机的安全至关重要。旋翼故障诊断技术仍是直升机健康与使用监测系统(Health and usage monitoring system, HUMS)领域的薄弱环节,开发旋翼故障诊断技术具有重要价值。基于信息融合技术... 旋翼作为直升机的升力面和操作面,其健康状态对直升机的安全至关重要。旋翼故障诊断技术仍是直升机健康与使用监测系统(Health and usage monitoring system, HUMS)领域的薄弱环节,开发旋翼故障诊断技术具有重要价值。基于信息融合技术,首先分析了旋翼故障的诊断机理,建立了旋翼故障模型,通过流固耦合仿真获取了不同故障下桨叶、轮毂和机身的故障特征信息,生成数据集进行网络训练和验证。然后,利用遗传算法反向传播(Genetic algorithm-backpropagation, GA-BP)优化神经网络诊断3种类型的直升机旋翼故障,即后缘调整片误调、变距拉杆误调和桨叶质量不平衡。3个逐级神经网络分别对旋翼故障类型、故障位置和故障程度进行了诊断识别。最后采用加权的Dempster-Shafer(D-S)证据理论对旋翼故障进行诊断和分析。结果证明基于改进D-S证据理论的旋翼故障诊断方法能够成功应用到旋翼故障诊断中,并具有良好的识别效果。 展开更多
关键词 旋翼系统 故障诊断 GA-BP神经网络 信息融合技术 D-s证据理论
下载PDF
基于D-S证据理论改进AHP-熵权的流域洪涝灾害评估研究
7
作者 苑希民 高瑞梅 +1 位作者 田福昌 侯玮 《水资源与水工程学报》 CSCD 北大核心 2024年第1期9-16,共8页
考虑致灾因子危险性、孕灾环境敏感性以及承灾体易损性,选取指标构建小清河流域洪涝灾害风险评估指标体系,提出一种基于D-S证据理论的改进AHP-熵权法计算指标权重,求取洪涝灾害风险指数,运用自然断点分级法确定洪涝灾害风险等级,分析小... 考虑致灾因子危险性、孕灾环境敏感性以及承灾体易损性,选取指标构建小清河流域洪涝灾害风险评估指标体系,提出一种基于D-S证据理论的改进AHP-熵权法计算指标权重,求取洪涝灾害风险指数,运用自然断点分级法确定洪涝灾害风险等级,分析小清河流域洪涝灾害风险空间分布情况。结果表明:小清河流域洪涝灾害风险总体上表现出南低北高的趋势,其中高风险区和较高风险区分别占流域面积的8.7%和14.3%,主要分布在小清河干流以及主要支流两岸。所得评估结果同“利奇马”台风发生期间实际洪灾风险分布情况一致,对比证明基于D-S证据理论的改进AHP-熵权法优于AHP和熵权法,可为小清河流域防洪减灾决策提供依据。 展开更多
关键词 D-s证据理论 AHP 熵权法 洪涝灾害评估 小清河流域
下载PDF
Continuum Skyrme Hartree-Fock-Bogoliubov theory with Green’s function method for neutron-rich Ca,Ni,Zr,and Sn isotopes
8
作者 En-Bo Huo Ke-Ran Li +2 位作者 Xiao-Ying Qu Ying Zhang Ting-Ting Sun 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第7期162-178,共17页
The possible exotic nuclear properties in the neutron-rich Ca,Ni,Zr,and Sn isotopes are examined with the continuum Skyrme Hartree-Fock-Bogoliubov theory in the framework of the Green’s function method.The pairing co... The possible exotic nuclear properties in the neutron-rich Ca,Ni,Zr,and Sn isotopes are examined with the continuum Skyrme Hartree-Fock-Bogoliubov theory in the framework of the Green’s function method.The pairing correlation,the couplings with the continuum,and the blocking effects for the unpaired nucleon in odd-A nuclei are properly treated.The Skyrme interaction SLy4 is adopted for the ph channel and the density-dependentinteraction is adopted for the pp chan-nel,which well reproduce the experimental two-neutron separation energies S_(2n)and one-neutron separation energies Sn.It is found that the criterion S_(n)>0 predicts a neutron drip line with neutron numbers much smaller than those for S_(2n)>0.Owing to the unpaired odd neutron,the neutron pairing energies−E_(pair)in odd-A nuclei are much lower than those in the neighbor-ing even-even nuclei.By investigating the single-particle structures,the possible halo structures in the neutron-rich Ca,Ni,and Sn isotopes are predicted,where sharp increases in the root-mean-square(rms)radii with significant deviations from the traditional rA^(1∕3)rule and diffuse spatial density distributions are observed.Analyzing the contributions of various partial waves to the total neutron densityρlj(r)∕ρ(r)reveals that the orbitals located around the Fermi surface-particularly those with small angular momenta-significantly affect the extended nuclear density and large rms radii.The number of neutrons Nλ(N_(0))occupying above the Fermi surfacen(continuum threshold)is discussed,whose evolution as a function of the mass number A in each isotope is consistent with that of the pairing energy,supporting the key role of the pairing correlation in halo phenomena. 展开更多
关键词 Neutron-rich nuclei Neutron halo skyrme Hartree-Fock-Bogoliubov theory Green’s function method
下载PDF
Nash Embedding of Witten’s M-Theory and the Hawking-Hartle Quantum Wave of Dark Energy 被引量:2
9
作者 Mohamed S. El Naschie 《Journal of Modern Physics》 2013年第10期1417-1428,共12页
Euclidean embedding of the 11-dimensional M-theory turned out to require a very large space leaving lavish amounts of 242 dimensional pseudo truly empty “regions” devoid of space and time and consequently of anythin... Euclidean embedding of the 11-dimensional M-theory turned out to require a very large space leaving lavish amounts of 242 dimensional pseudo truly empty “regions” devoid of space and time and consequently of anything resembling ordinary physical energy density. It is shown here using Nash embedding that the ratio of “solid” M-theory spacetime to its required embedding “non-spacetime” is 1/22 for a classical theory and 1/22.18033989 for an analogous fractal theory. This then leads to a maximal ordinary energy density equation equal to that of Einstein’s famous formula E=mc2 but multiplied with in full agreement with previous results obtained using relatively more conventional methods including running the electromagnetic fine structure constant in the exact solution of the hydrogen atom. Consequently, the new equation corresponds to a quantum relativity theory which unlike Einstein’s original equation gives quantitative predictions which agree perfectly with the cosmological measurements of WMAP and the analysis of certain supernova events. Never the less in our view dark energy also exists being the energy of the quantum wave amounting to 95.5 present of the total Einstein theoretical energy which is blind to any distinction between ordinary energy of the quantum particle and the dark energy of the quantum wave. However, since measurement leads to the collapse of the Hawking-Hartle quantum wave, dark energy being a quantum wave non-ordinary energy could not possibly be measured in the usual way unless highly refined quantum wave non-demolition technology is developed if possible. It is a further reason that dark energy having a different sign to ordinary energy is the cause behind the anti gravity force which is pushing the universe apart and accelerating cosmic expansion. Consequently it can be seen as the result of anticlastic Cartan-like curvature caused by extra compactified dimensions of spacetime. A simple toy model demonstration of the effect of curvature in a “material” space is briefly discussed. 展开更多
关键词 NAsH Euclidean EMBEDDING QUANTUM Entanglement Dark ENERGY of the QUANTUM WAVE QUANTUM Gravity Ordinary ENERGY of the QUANTUM Particle Hawking-Hartle WAVE of the Cosmos QUANTUM WAVE Non-Demolition witten’s M-theory
下载PDF
Energy-Efficient Clustering Using Optimization with Locust Game Theory
10
作者 P.Kavitha Rani Hee-Kwon Chae +1 位作者 Yunyoung Nam Mohamed Abouhawwash 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期2591-2605,共15页
Wireless sensor networks(WSNs)are made up of several sensors located in a specific area and powered by a finite amount of energy to gather environmental data.WSNs use sensor nodes(SNs)to collect and transmit data.Howe... Wireless sensor networks(WSNs)are made up of several sensors located in a specific area and powered by a finite amount of energy to gather environmental data.WSNs use sensor nodes(SNs)to collect and transmit data.However,the power supplied by the sensor network is restricted.Thus,SNs must store energy as often as to extend the lifespan of the network.In the proposed study,effective clustering and longer network lifetimes are achieved using mul-ti-swarm optimization(MSO)and game theory based on locust search(LS-II).In this research,MSO is used to improve the optimum routing,while the LS-II approach is employed to specify the number of cluster heads(CHs)and select the best ones.After the CHs are identified,the other sensor components are allo-cated to the closest CHs to them.A game theory-based energy-efficient clustering approach is applied to WSNs.Here each SN is considered a player in the game.The SN can implement beneficial methods for itself depending on the length of the idle listening time in the active phase and then determine to choose whether or not to rest.The proposed multi-swarm with energy-efficient game theory on locust search(MSGE-LS)efficiently selects CHs,minimizes energy consumption,and improves the lifetime of networks.The findings of this study indicate that the proposed MSGE-LS is an effective method because its result proves that it increases the number of clusters,average energy consumption,lifespan extension,reduction in average packet loss,and end-to-end delay. 展开更多
关键词 Wireless sensor network CLUsTERING routing cluster head energy consumption network’s lifetime multi swarm optimization game theory
下载PDF
Theory Critique of Kristen Swanson’s Theory of Caring
11
作者 Ali M. Al Yasin 《Open Journal of Nursing》 2023年第8期528-536,共9页
Theory is considered essential for integral assessment, adopting its foundations and concepts is of great utility. The theory provides different templates to help nurses provide care that respects patients and improve... Theory is considered essential for integral assessment, adopting its foundations and concepts is of great utility. The theory provides different templates to help nurses provide care that respects patients and improves outcomes. Through understanding the intersection of nursing, patients, health, and the environment, theories aim to simplify the complicated, ever-evolving relationship that nurses have with their profession. Nursing theory helps distinguish nursing as a separate discipline from medicine and related sciences, and assists nurses in understanding their patients and their needs. The behaviors of healthcare providers affect how patients participate in and experience care situations. In the nursing discipline, the theoretical structures of caring have been established as the core concept of guidance in all nurses’ work. The aim of this paper is to develop a critique of Kristen Swanson’s theory of caring—a theory structured around five caring principles (maintaining belief, knowing, being with, doing for, and enabling) by applying it to nursing practice. When applied to nursing practice, each of these five stages stimulates the caregiver’s attitude, which in turn improves the overall patient’s well-being. Implications to nursing practice are mentioned [1] [2]. 展开更多
关键词 Kristen swanson’s theory theory Critique Caring Principles Nursing Practice simulation Practice Creative Interventions
下载PDF
基于理性扩展热力学的L-S热声弹性理论框架
12
作者 李元燮 刘财 《吉林大学学报(地球科学版)》 CAS CSCD 北大核心 2024年第2期655-687,共33页
本文基于连续介质力学和理性扩展热力学分析流程,将L-S(Lord and Shulman)热弹性理论与声弹性理论相结合,建立L-S热声弹性理论的基本框架,包括运动学、力学与热力学、本构方程与演化方程、基本场方程四部分。在运动学部分,区分了Lagrang... 本文基于连续介质力学和理性扩展热力学分析流程,将L-S(Lord and Shulman)热弹性理论与声弹性理论相结合,建立L-S热声弹性理论的基本框架,包括运动学、力学与热力学、本构方程与演化方程、基本场方程四部分。在运动学部分,区分了Lagrange描述和Euler描述,以及3种不同的状态和构形,同时针对热声弹性情况定义了两类从自然状态到初始状态的转变过程;在力学与热力学部分,给出了质量守恒定律、动量守恒定律、角动量守恒定律、能量守恒定律以及熵产不等式,从而引出经典不可逆热力学的局限性;在本构方程与演化方程部分,介绍了扩展不可逆热力学原理,并基于理性扩展热力学流程,推导了从自然状态到初始状态、从初始状态到最终状态的热声弹性本构方程与演化方程,将热流作为本构自变量并考虑了热流与应变和温度的相关性;在最后一部分给出了基本场方程的运动方程形式和适用于数值模拟的一阶速度-应力-热流-温度微分方程。 展开更多
关键词 L-s理论 热弹性 声弹性 连续介质力学 理性扩展热力学
下载PDF
Hilbert’s First Problem and the New Progress of Infinity Theory
13
作者 Xijia Wang 《Journal of Applied Mathematics and Physics》 2023年第4期891-904,共14页
In the 19th century, Cantor created the infinite cardinal number theory based on the “1-1 correspondence” principle. The continuum hypothesis is proposed under this theoretical framework. In 1900, Hilbert made it th... In the 19th century, Cantor created the infinite cardinal number theory based on the “1-1 correspondence” principle. The continuum hypothesis is proposed under this theoretical framework. In 1900, Hilbert made it the first problem in his famous speech on mathematical problems, which shows the importance of this question. We know that the infinitesimal problem triggered the second mathematical crisis in the 17-18th centuries. The Infinity problem is no less important than the infinitesimal problem. In the 21st century, Sergeyev introduced the Grossone method from the principle of “whole is greater than part”, and created another ruler for measuring infinite sets. The discussion in this paper shows that, compared with the cardinal number method, the Grossone method enables infinity calculation to achieve a leap from qualitative calculation to quantitative calculation. According to Grossone theory, there is neither the largest infinity and infinitesimal, nor the smallest infinity and infinitesimal. Hilbert’s first problem was caused by the immaturity of the infinity theory. 展开更多
关键词 Hilbert’s First Problem Cardinal Numbers Method Grossone Method Continuum Paradox Infinity theory
下载PDF
基于改进D-S理论的多时刻空中目标威胁评估
14
作者 李山 权文 +2 位作者 李昉 苏力德 黄呈祥 《电光与控制》 CSCD 北大核心 2024年第3期48-52,共5页
针对单时刻空中目标威胁评估存在的抗干扰能力弱、可靠性不足等问题,建立一种基于改进D-S证据理论的多时刻空中目标威胁评估模型。首先,根据空战时间线,定义多时刻空中目标威胁评估时段范围;然后,在单时刻空中目标威胁等级概率分配基础... 针对单时刻空中目标威胁评估存在的抗干扰能力弱、可靠性不足等问题,建立一种基于改进D-S证据理论的多时刻空中目标威胁评估模型。首先,根据空战时间线,定义多时刻空中目标威胁评估时段范围;然后,在单时刻空中目标威胁等级概率分配基础上,利用D-S证据理论融合各时刻证据信息;同时,针对D-S证据理论不能处理高冲突证据的弊端及其现有改进方法计算量较大的不足,引入偏移度的概念,确定各时刻证据源权重,对加权证据进行D-S融合。数值算例表明,该模型算法复杂度低;能有效处理波动数据、稳定性强,并且可减弱高冲突证据融合对威胁评估带来的不利影响,为最终决策提供了更准确的判别依据。 展开更多
关键词 威胁评估 空中目标 D-s证据理论 偏移度
下载PDF
Resolving the“Matteo Ricci Puzzle”:Top-Level Design of the Grand Canal of China Based on the Ternary Leadership Theory
15
作者 LI Jing TIAN Dexin 《Journalism and Mass Communication》 2023年第1期1-16,共16页
Guided by the ternary leadership theory from the perspective of social psychology,this paper explores the impacts of authoritarian,benevolent,and moral leadership on the top design of the Grand Canal of China in terms... Guided by the ternary leadership theory from the perspective of social psychology,this paper explores the impacts of authoritarian,benevolent,and moral leadership on the top design of the Grand Canal of China in terms of its water management practice,while providing reference for resolving the“Matteo Ricci Puzzle”.The research findings are threefold:first,authoritarian as it is,the central government of China formulates relevant laws and regulations to provide legal system insurance for the construction of the Grand Canal Cultural Belt,thus providing the blueprint for constructing the“bright cultural belt,green ecological belt and colorful tourism belt of the Grand Canal”.Second,led by the Central Government,sticking to benevolent and moral leadership,China advocates scientific water management concepts and methods,and gives long-term and comprehensive care to the well-being of the people along the banks of the Grand Canal.Finally,the top-level design of the Grand Canal of China is based on the ternary leadership theory rooted in social psychology and has formulated a set of properly-scheduled,reasonably-coordinated,and flexibly-operated management system for the fundamental interests of the people and long-term goals of the country. 展开更多
关键词 social psychology ternary leadership theory top design management of the Grand Canal of China Matteo Ricci’s puzzle
下载PDF
H_(2)S、HCN、PH_(3)在FeO(100)表面吸附的密度泛函理论研究
16
作者 杨蒙 彭国建 +4 位作者 刘永军 张艳琨 杨春晓 夏福婷 张秋林 《原子与分子物理学报》 CAS 北大核心 2024年第1期29-36,共8页
基于密度泛函理论研究了H_(2)S、HCN、PH_(3)在FeO(100)表面的吸附行为,其吸附位点主要考虑四个:Fe-top(铁顶位)、O-top(氧顶位)、Hollow(空位)、Bridge(桥位).结果表明H_(2)S吸附在O-top吸附位点的吸附能最小,为-1.02 eV,即在该位点的... 基于密度泛函理论研究了H_(2)S、HCN、PH_(3)在FeO(100)表面的吸附行为,其吸附位点主要考虑四个:Fe-top(铁顶位)、O-top(氧顶位)、Hollow(空位)、Bridge(桥位).结果表明H_(2)S吸附在O-top吸附位点的吸附能最小,为-1.02 eV,即在该位点的吸附体系最稳定.当HCN吸附在FeO(100)表面时,各吸附位点的稳定顺序为Hollow>Fe-top>Bridge>O-top.PH_(3)的最稳定的吸附位点与H_(2)S的一致,为O-top吸附位点,其吸附能为-1.11 eV.当H_(2)S吸附在O-top吸附位点时,H_(2)S与FeO(100)表面的电荷转移量最多,说明该吸附构型最稳定,而HCN吸附在FeO(100)表面,在Hollow吸附位点的电荷转移量最多,也即该吸附位点属于最稳定吸附位点.PH_(3)与FeO(100)表面之间的电荷转移量最多的吸附位点与H_(2)S的相同.当H_(2)S和PH_(3)吸附在O-top吸附位点时,吸附后的态密度曲线整体向低能级移动,峰值降低,其吸附结构变得更加稳定.而HCN吸附在Hollow位点时,吸附后的HCN态密度曲线向能量更低的区域移动,吸附体系变得更稳定. 展开更多
关键词 密度泛函理论 H_(2)s HCN PH_(3) 吸附能
下载PDF
6-巯基-5-三唑并[4,3-b]-s-四嗪(MTT)的密度泛函理论研究
17
作者 赵宁 陈慧 +2 位作者 任黎英 邵长斌 陈玉锋 《原子与分子物理学报》 CAS 北大核心 2024年第1期37-42,共6页
采用密度泛函理论(Density functional theory,DFT),在B3LYP/6-31g(d)(C,H,N,S),Ag原子采用LanL2d赝势基组水平上对甲醛(HCHO)与4-氨基-5肼基-3-巯基-1,2,4-三唑(4-amino-5-hydrazino-3-mercapto-1,2,4-triazole,AHMT)衍生化反应生的成... 采用密度泛函理论(Density functional theory,DFT),在B3LYP/6-31g(d)(C,H,N,S),Ag原子采用LanL2d赝势基组水平上对甲醛(HCHO)与4-氨基-5肼基-3-巯基-1,2,4-三唑(4-amino-5-hydrazino-3-mercapto-1,2,4-triazole,AHMT)衍生化反应生的成产物6-巯基-5-三唑并[4,3-b]-s-四嗪(6-mercapto-5-triazolo[4,3-b]-s-tetrazine,MTT)及其银配合物进行结构优化,优化结果表明MTT的结构是一个近平面结构.通过对频率计算,获得MTT分子及其银配合物的拉曼光谱,对400-1800 cm^(-1)波段内的拉曼光谱特征峰进行了指认.同时讨论了MTT分子的表面静电势,分析可能发生化学反应的位点.并采用含时密度泛函理论(Time Dependent density functional theory,TDDFT)对MTT分子与Ag3配合物的激发态进行了计算分析,并使用电荷转移光谱对Ag配合物与MTT之间电荷转移关系进行了研究.该研究对MTT分子的光谱测定和电子性质提供了理论基础. 展开更多
关键词 密度泛函理论 拉曼光谱 紫外光谱 6-巯基-5-三唑并[4 3-b]-s-四嗪
下载PDF
Possible Evolutionary Models in the Initially Hydride Earth Theory
18
作者 Kudryavtsev Pavel 《International Journal of Geosciences》 CAS 2023年第5期377-426,共50页
A modern view of the properties of chemical elements has confirmed the theory of the hot origin of the Earth. The next step in developing this theory was the hypothesis of the initial hydride Earth. In this work, we a... A modern view of the properties of chemical elements has confirmed the theory of the hot origin of the Earth. The next step in developing this theory was the hypothesis of the initial hydride Earth. In this work, we attempted to find additional evidence for this hypothesis and show additional effects that flow from it. The effect of the physical properties of atoms and ions on their behavior during the formation of the Earth was studied. The maximum contribution to the distribution of elements was made by those elements whose content in the original protoplanets of the disk was the maximum. Correlation dependence is obtained, which allows one to calculate the distribution of elements in the protoplanetary disk. It was shown that hydrogen was the main element in the proto substance located in the zone of the Earth’s formation. In this case, various chemical compounds formed, most represented by hydrogen compounds—hydrides. Since the pressure inside the Earth is 375 GPa, this factor forces the chemical compounds to adopt stoichiometry and structure that would not be available in atmospheric conditions. It is shown that many chemical elements at high pressure in a hydrogen medium form simple hydrides and super hydrides—polyhydrides with high hydrogen content. Pressure leads to a higher density of matter inside the planet. Given the possibility of forming polyhydrides, there is the possibility of binding the initially available hydrogen in an amount that can reach 49.3 mole%. Young Earth could contain about 10.7 mass% of hydrogen in hydrides, polyhydrides, and adsorbed form is almost twice higher than previous estimates. This fact additionally confirms the theory of the original hydride Earth. In hydrides, the occurrence of the phenomenon of superconductivity was discovered. Polyhydrides were shown as potential superconductors with a high critical temperature above 200 K. We, based on these data, hypothesized the presence of superconducting properties in the Earth’s core, which explains the presence of a magnetic field in the Earth, as well as the unevenness and instability of this field and the possibility of migration of the Earth’s poles. The fact that the Earth has a hydroid core causes its change in time due to the instability of hydrides. Arranged several possible models of the destruction of the Earth’s core. The calculations showed that both models give close results. These results give predictions that can be measured. The proposed models also made it possible to estimate the initial size of the Earth. Possible ways of further testing the hypothesis of the initial hydride Earth is shown. 展开更多
关键词 theory of the Hot Origin of the Earth Magnetic separation of Elements Atom Ionization Energy Hydrides Polyhydrides Earth Expansion superconductivity of the Earth’s Core
下载PDF
基于Swanson关怀理论的护理干预在早产儿母亲中的应用
19
作者 黄丽玲 林梅 +5 位作者 黄芝蓉 许冬梅 黄婷 王嘉莹 马妮妮 李玉娟 《全科护理》 2024年第8期1459-1464,共6页
目的:探讨以Swanson关怀理论为框架的护理干预在早产儿母亲中的应用效果。方法:采取便利抽样法选取2022年1月-5月入住百色市某三级甲等医院新生儿重症监护室(NICU)治愈出院的40例早产儿母亲作为对照组,选取2022年6月-10月入住百色市某... 目的:探讨以Swanson关怀理论为框架的护理干预在早产儿母亲中的应用效果。方法:采取便利抽样法选取2022年1月-5月入住百色市某三级甲等医院新生儿重症监护室(NICU)治愈出院的40例早产儿母亲作为对照组,选取2022年6月-10月入住百色市某三级甲等医院NICU治愈出院的40例早产儿母亲作为试验组。对照组实施NICU常规护理,试验组在对照组干预的基础上实施基于Swanson关怀理论的护理干预,比较两组早产儿母亲干预前后疾病不确定感、希望水平、育儿胜任感得分情况。结果:干预后试验组早产儿母亲疾病不确定感得分明显低于对照组(P<0.001),希望水平得分明显高于对照组(P<0.001);出院时及出院1个月后试验组早产儿母亲育儿胜任感得分明显高于对照组(P<0.001)。结论:基于Swanson关怀理论的护理干预可有效降低早产儿母亲疾病不确定感水平,提高其希望水平,增强其育儿胜任感,有利于早产儿顺利从医院过渡至家庭。 展开更多
关键词 swanson关怀理论 早产儿母亲 疾病不确定感 希望水平 育儿胜任感量表
下载PDF
基于AHP-DS异质数据融合的建筑空间占用感知算法
20
作者 杨镇宇 吴晓菲 +2 位作者 魏昕 顾小军 唐觉民 《软件》 2024年第3期42-47,共6页
智慧建筑智能控制系统旨在优化建筑物的建筑空间舒适度及能源分配,近年来受到了广泛关注,而建筑空间占用信息对智慧建筑管理系统的决策具有重要作用。现有建筑空间占用感知方法尚未针对如何融合具有不确定性、冲突性的多源数据问题提出... 智慧建筑智能控制系统旨在优化建筑物的建筑空间舒适度及能源分配,近年来受到了广泛关注,而建筑空间占用信息对智慧建筑管理系统的决策具有重要作用。现有建筑空间占用感知方法尚未针对如何融合具有不确定性、冲突性的多源数据问题提出有效解决方案,基于此,本文将D-S证据理论引入建筑空间占用预测中,并构建了基于建筑空间占用检测的mass函数确保D-S证据理论在该应用中的性能。另外,本文引入层次分析法(Analytic Hierarchy Process,AHP)解决多源异构数据源间的冲突所导致的建筑空间占用误测的问题,以提升感知精准度和系统性能。 展开更多
关键词 智慧建筑 建筑空间占用检测 D-s证据理论 多源异构数据融合
下载PDF
上一页 1 2 200 下一页 到第
使用帮助 返回顶部