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Langmuir-Schaefer Film Investigation and Density Functional Theory Band Gap Calculations of Calix[n]arene-Para-Aminobenzoic Acid for Drug Nanosensor Application
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作者 WONG Yeong Yi F L Supian +2 位作者 A Radzwan M Musa N F N Abd Karim 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第5期1311-1318,共8页
Calix[n]arenes was utilized to detect PABA,the primary sunscreen component.This study investigates the interaction of calix[4]arene(C4),calix[6]arene(C6),and PABA using the Langmuir method and first-principle density ... Calix[n]arenes was utilized to detect PABA,the primary sunscreen component.This study investigates the interaction of calix[4]arene(C4),calix[6]arene(C6),and PABA using the Langmuir method and first-principle density functional theory(DFT).Using the Langmuir-Schaefer(LS)technique,an ultrathin film composed of calix[n]arenes and their complexes with PABA was deposited on various substrates.Based on the Langmuir study,the PABA molecule was bonded to the lower rims of both C4 and C6 with the host-guest ratio of 1:1.All of the LS films formed were then characterized by ultravioletvisible spectroscopy(UV-Vis),Fourier-transform infrared spectroscopy(FTIR)and carbon,hydrogen,nitrogen,sulfur elemental analyzer(CHNS).The band gap reduction obtained in the DFT study denotes the charge transfer interaction with promising reactivity between the calix[n]arenes and PABA.The sensing of PABA by C4 and C6 is successful based on the formation of bonding between them due to the hosts’effective trapping capacity.The outcomes of this study could be applied to drug delivery systems for future pharmaceutical and medical applications. 展开更多
关键词 calix[n]arenes band gap density functional theory Langmuir-Schaefer PABA sensor
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Study on the interannual variability of the Kerama Gap transport and its relation to the Kuroshio/Ryukyu Current system
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作者 Han Zhou Kai Yu +3 位作者 Jianhuang Qin Xuhua Cheng Meixiang Chen Changming Dong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期1-14,共14页
An analysis of a 68-year monthly hindcast output from an eddy-resolving ocean general circulation model reveals the relationship between the interannual variability of the Kerama Gap transport(KGT)and the Kuroshio/Ryu... An analysis of a 68-year monthly hindcast output from an eddy-resolving ocean general circulation model reveals the relationship between the interannual variability of the Kerama Gap transport(KGT)and the Kuroshio/Ryukyu Current system.The study found a significant difference in the interannual variability of the upstream and downstream transports of the East China Sea-(ECS-)Kuroshio and the Ryukyu Current.The interannual variability of the KGT was found to be of paramount importance in causing the differences between the upstream and downstream ECS-Kuroshio.Additionally,it contributed approximately 37%to the variability of the Ryukyu Current.The interannual variability of the KGT was well described by a two-layer rotating hydraulic theory.It was dominated by its subsurface-intensified flow core,and the upper layer transport made a weaker negative contribution to the total KGT.The subsurface flow core was found to be mainly driven by the subsurface pressure head across the Kerama Gap,and the pressure head was further dominated by the subsurface density anomalies on the Pacific side.These density anomalies could be traced back to the eastern open ocean,and their propagation speed was estimated to be about 7.4 km/d,which is consistent with the speed of the local first-order baroclinic Rossby wave.When the negative(positive)density anomaly signal reached the southern region of the Kerama Gap,it triggered the increase(decrease)of the KGT towards the Pacific side and the formation of an anticyclonic(cyclonic)vortex by baroclinic adjustment.Meanwhile,there is an increase(decrease)in the upstream transport of the entire Kuroshio/Ryukyu Current system and an offshore flow that decreases(increases)the downstream Ryukyu Current. 展开更多
关键词 Kerama gap KUROSHIO Ryukyu Current OGCM for the Earth Simulator(OFES) hydraulic theory
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Investigations of phase transition, elastic and thermodynamic properties of GaP by using the density functional theory 被引量:2
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作者 刘丽 韦建军 +3 位作者 安辛友 王雪敏 刘会娜 吴卫东 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第10期349-354,共6页
The phase transition of gallium phosphide (GAP) from zinc-blende (ZB) to a rocksalt (RS) structure is investigated by the plane-wave pseudopotential density functional theory (DFT). Lattice constant a0, elasti... The phase transition of gallium phosphide (GAP) from zinc-blende (ZB) to a rocksalt (RS) structure is investigated by the plane-wave pseudopotential density functional theory (DFT). Lattice constant a0, elastic constants cij, bulk modulus B0 and the pressure derivative of bulk modulus B0 are calculated. The results are in good agreement with numerous experimental and theoretical data. From the usual condition of equal enthalpies, the phase transition from the ZB to the RS structure occurs at 21.9 GPa, which is close to the experimental value of 22.0 GPa. The elastic properties of GaP with the ZB structure in a pressure range from 0 GPa to 21.9 GPa and those of the RS structure in a pressure range of pressures from 21.9 GPa to 40 GPa are obtained. According to the quasi-harmonic Debye model, in which the phononic effects are considered, the normalized volume V/Vo, the Debye temperature 8, the heat capacity Cv and the thermal expansion coefficient a are also discussed in a pressure range from 0 CPa to 40 GPa and a temperature range from 0 K to 1500 K. 展开更多
关键词 gap phase transition density functional theory thermodynamic properties
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Dynamic development model for long gap discharge streamer-leader system based on fractal theory 被引量:1
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作者 Jianghai GENG Quansheng WANG +3 位作者 Xiaomin LIU Ping WANG Fangcheng LYU Yujian DING 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第9期68-76,共9页
Establishing a long air gap discharge model considering the streamer-leader transition and randomness of the discharge path is of great signiflcance to improve the accuracy of discharge characteristic prediction and o... Establishing a long air gap discharge model considering the streamer-leader transition and randomness of the discharge path is of great signiflcance to improve the accuracy of discharge characteristic prediction and optimize external insulation design.Based on fractal theory and thermal ionization theory of streamer-leader transition,this work establishes a dynamic development model for the long air gap discharge streamer-leader system,which includes streamer inception,streamer development,leader inception,development of streamer-leader system and flnal jump.The positive discharge process of a 3 m rod plate is simulated to obtain the fractal distribution of the discharge path and the law of leader development for comparison with the discharge test results.The results show that the simulation model is similar to test results in the development characteristics of leader path distribution,each stage time and leader velocity.Finally,a simulation calculation of a 50%breakdown voltage of the rod-plate gap and ball-plate gap is carried out,with results fairly consistent with test data,proving the effectiveness and practicality of the model. 展开更多
关键词 long air gap fractal theory thermal ionization streamer-leader system simulation model
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Boundary Hamiltonian Theory for Gapped Topological Orders 被引量:2
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作者 胡愈挺 万义顿 吴咏时 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第7期207-211,共5页
We report our systematic construction of the lattice Hamiltonian model of topological orders on open surfaces, with explicit boundary terms. We do this mainly for the Levin-Wen string-net model. The full Hamiltonian i... We report our systematic construction of the lattice Hamiltonian model of topological orders on open surfaces, with explicit boundary terms. We do this mainly for the Levin-Wen string-net model. The full Hamiltonian in our approach yields a topologically protected, gapped energy spectrum, with the corresponding wave functions robust under topology-preserving transformations of the lattice of the system. We explicitly present the wavefunctions of the ground states and boundary elementary excitations. The creation and hopping operators of boundary quasi-particles are constructed. It is found that given a bulk topological order, the gapped boundary conditions are classified by Frobenius algebras in its input data. Emergent topological properties of the ground states and boundary excitations are characterized by (bi-) modules over Frobenius algebras. 展开更多
关键词 Boundary Hamiltonian theory for gapped Topological Orders
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Translation Quality Assessment: Bridge the Gap between Theory and Practice
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作者 WANG Jun-song 《Journal of Literature and Art Studies》 2017年第12期1701-1706,共6页
Translation Quality Assessment (TQA) is a central concern for both academic research and translation practice. Yet consensus on the issue has almost never been reached among theorists and practitioners. In this pape... Translation Quality Assessment (TQA) is a central concern for both academic research and translation practice. Yet consensus on the issue has almost never been reached among theorists and practitioners. In this paper, a detailed comparison between academic and professional assessment has been made mainly in terms of text type, assessment criteria and models. It is believed that a "one size fits all" model across academy and industry is neither possible nor necessary. However, the gaps in between could be narrowed down by increasing communication and cooperation between theorists and practitioners, who are advised to turn their focus to translator's competence and evaluation process. 展开更多
关键词 Translation Quality Assessment gapS theory and practice
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Study the Structural, Electronic, Optical Properties of CZTS Compound after Doping Ba at Zn Site and Si at Sn Site Using Density Functional Theory (DFT)
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作者 Fatema Najrin Rabeya Bakar Sarna +4 位作者 Sayedul Hasan Shariful Islam Budrun Neher Md. Mahbubur Rahman Bhuiyan Farid Ahmed 《Materials Sciences and Applications》 2024年第9期305-319,共15页
The structural, electronic, and optical properties of Cu2Zn1−xBaxSn1−ySiyS4 compounds have been calculated using GGA-PBE function within the framework of Density Functional Theory (DFT). In the present work, lattice p... The structural, electronic, and optical properties of Cu2Zn1−xBaxSn1−ySiyS4 compounds have been calculated using GGA-PBE function within the framework of Density Functional Theory (DFT). In the present work, lattice parameters remained the same, that is tetragonal crystal structure for 0% and 100% doping concentration. The electronic band gap of Cu2Zn1−xBaxSn1−ySiyS4 compounds has been gradually increased for continuous increment of doping concentration where the highest electronic band gap is 1.117 eV for Cu2BaSiS4 structure. Moreover, the band gap changes from direct to indirect band gap with the increase of doping concentration in the parent compound. The absorption coefficient has been found to be high (> 104 cm−1) in UV-region for all the doping concentration which makes the studied compound as a potential candidate of absorber layer in the UV detector. The theoretical study of the effect of double doping in the CZTS compound is very interesting for improving the quality of it and it would be a reference for the theoretical and experimental researchers. 展开更多
关键词 Photovoltaics Absorber Layer Density Functional theory (DFT) Band gap Solar Cell
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Yield gap and resource utilization efficiency of three major food crops in the world——A review 被引量:5
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作者 RONG Liang-bing GONG Kai-yuan +5 位作者 DUAN Feng-ying LI Shao-kun ZHAO Ming HE Jianqiang ZHOU Wen-bin YU Qiang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第2期349-362,共14页
Yield gap analysis could provide management suggestions to increase crop yields,while the understandings of resource utilization efficiency could help judge the rationality of the management.Based on more than 110 pub... Yield gap analysis could provide management suggestions to increase crop yields,while the understandings of resource utilization efficiency could help judge the rationality of the management.Based on more than 110 published papers and data from Food and Agriculture Organization (FAO,www.fao.org/faostat) and the Global Yield Gap and Water Productivity Atlas (www.yieldgap.org),this study summarized the concept,quantitative method of yield gap,yield-limiting factors,and resource utilization efficiency of the three major food crops (wheat,maize and rice).Currently,global potential yields of wheat,maize and rice were 7.7,10.4 and 8.5 t ha^(–1),respectively.However,actual yields of wheat,maize and rice were just 4.1,5.5 and 4.0 t ha^(–1),respectively.Climate,nutrients,moisture,crop varieties,planting dates,and socioeconomic conditions are the most mentioned yield-limiting factors.In terms of resource utilization,nitrogen utilization,water utilization,and radiation utilization efficiencies are still not optimal,and this review has summarized the main improvement measures.The current research focuses on quantitative potential yield and yield gap,with a rough explanation of yield-limiting factors.Subsequent research should use remote sensing data to improve the accuracy of the regional scale and use machine learning to quantify the role of yield-limiting factors in yield gaps and the impact of change crop management on resource utilization efficiency,so as to propose reasonable and effective measures to close yield gaps. 展开更多
关键词 food crops YIELD yield gap resource utilization efficiency yield-limiting factor
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基于Info-Gap理论的基桩下伏岩溶顶板稳定性的主动分析方法 被引量:21
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作者 曹文贵 李媛 翟友成 《岩石力学与工程学报》 EI CAS CSCD 北大核心 2013年第2期393-400,共8页
针对因不能获得足够数据信息量而无法准确描述不确定参量的分布形态问题,引入Information-Gap(简称为Info-Gap)理论,首先,通过对不确定参量的不确定性程度度量方法和满足预定功能的不确定参量的允许不确定性程度变化幅度确定方法的研究... 针对因不能获得足够数据信息量而无法准确描述不确定参量的分布形态问题,引入Information-Gap(简称为Info-Gap)理论,首先,通过对不确定参量的不确定性程度度量方法和满足预定功能的不确定参量的允许不确定性程度变化幅度确定方法的研究,建立基桩下伏岩溶顶板稳定性的不确定性分析的稳健可靠度分析模型;然后,基于现有岩溶顶板安全系数在不同失稳模式下的极限平衡分析方法,建立基桩下伏岩溶顶板功能输出响应模型,并在此基础上,基于区间组合分析法,建立基桩下伏岩溶顶板稳定性的稳健可靠度指标确定方法,从而提出基于Info-Gap理论的基桩下伏岩溶顶板稳定性的不确定性分析新方法。该方法对数据信息量要求低,无需掌握不确定参量的分布形态,是对现有相关理论与方法的补充与完善;而且,由于该方法将不确定参量区分为设计变量和设计参数,实现基桩下伏岩溶顶板稳定性在不同设计变量下不确定设计参数的允许不确定性程度的动态分析,因而,使该新方法既具有被动应对功能,又具有主动处置功能。最后,通过工程实例分析,表明所提方法的可行性与合理性。 展开更多
关键词 桩基础 岩溶 基桩 不确定性分析 Info-gap理论 岩溶顶板稳定性 稳健可靠度指标
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中药材GAP研究与实施的整体观 被引量:8
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作者 孟祥才 王喜军 都晓伟 《现代中药研究与实践》 CAS 2005年第1期18-22,共5页
GAP是一个复杂的系统 ,本文论述了源 库理论、化学调控及其它多学科领域对中药材产量和质量提高方面的重要意义 ;从整个生产过程与经济效益的关系 ,提出了规范化栽培和研究的重要性 ;在质量分析方面 。
关键词 整体观 gap 中药材 质量分析 多学科 研究 影响因素 规范化栽培 化学调控 产量
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基于Info-Gap决策的结构抗震稳健性优化设计 被引量:2
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作者 唐和生 范德伟 +1 位作者 李大伟 薛松涛 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2015年第5期21-28,共8页
针对结构抗震设计中存在严重不确定性问题,基于Info-Gap理论建立一种考虑地震设计谱参数不确定的结构抗震稳健性优化设计方法.该设计方法采用Info-Gap模型来描述地震设计谱中反映地面运动强度的水平地震影响系数最大值αmax和场地特征周... 针对结构抗震设计中存在严重不确定性问题,基于Info-Gap理论建立一种考虑地震设计谱参数不确定的结构抗震稳健性优化设计方法.该设计方法采用Info-Gap模型来描述地震设计谱中反映地面运动强度的水平地震影响系数最大值αmax和场地特征周期Tg的不确定,通过嵌套优化使结构设计满足结构的临界性能要求的同时实现最大化不确定的稳健性.通过对一个6层3跨的钢框架的抗震稳健性优化设计验证分析表明:这种基于满足性能的结构抗震设计需在满足结构性能需求和提高不确定稳健性之间进行权衡取舍;同时也证实该方法为在不易得到不确定性因素足够信息情况下的基于性能结构抗震可靠性设计提供了一条新思路. 展开更多
关键词 Info-gap理论 不确定 稳健性 抗震设计
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(GaP)_n和(GaP)_n^-(n=10~16)团簇的结构与稳定性研究 被引量:2
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作者 郭彩红 贾建峰 武海顺 《化学学报》 SCIE CAS CSCD 北大核心 2007年第17期1836-1840,共5页
采用密度泛函理论B3LYP/Lanl2dz方法对(GaP)n和(GaP)-n(n=10~16)团簇的一系列异构体的结构和稳定性进行了研究.讨论了中性团簇得到一个电子之后,几何结构和电子性质的变化.频率分析预测出最强吸收峰位于341~390cm-1区域.从能隙、结合... 采用密度泛函理论B3LYP/Lanl2dz方法对(GaP)n和(GaP)-n(n=10~16)团簇的一系列异构体的结构和稳定性进行了研究.讨论了中性团簇得到一个电子之后,几何结构和电子性质的变化.频率分析预测出最强吸收峰位于341~390cm-1区域.从能隙、结合能和能量二次差分等方面综合考虑,具有Th对称性的(GaP)12和(GaP)1-2分别是中性(GaP)n和阴离子(GaP)-n团簇中最稳定的,而具有Td点群结构的(GaP)16也比较稳定,究竟哪种结构易于合成还有待于实验的进一步证实.在相同理论水平上计算了基态(GaP)n(n=10~16)的绝热电子亲合势(AEAs)及其基态阴离子的垂直电离能(VDEs),这对以后的实验数据分析将有一定的参考价值. 展开更多
关键词 密度泛函理论 (gap)n和(gap)n^-团簇 垂直电离能 绝热电子亲合势
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中药材GAP种植基地建设探讨 被引量:4
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作者 王喆之 闫亚平 《世界科学技术-中医药现代化》 2003年第2期55-58,共4页
中药材GAP种植基地建设是影响药材生态经济效益的关键因素之一。在基地建设中应重视量化基地环境因子,以地选材,以材定地,完善栽培方法,深入研究加工工艺,实行规范的“公司+基地+科研单位+农户”的经营运作方式。运用系统论概念,将基地... 中药材GAP种植基地建设是影响药材生态经济效益的关键因素之一。在基地建设中应重视量化基地环境因子,以地选材,以材定地,完善栽培方法,深入研究加工工艺,实行规范的“公司+基地+科研单位+农户”的经营运作方式。运用系统论概念,将基地建成最大效益的生态经济复合体。 展开更多
关键词 中药材 gap 种植基地 品种栽培 运作机制 中国 生态经济
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硫钝化GaP(001)表面的结构及电学性质研究
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作者 李登峰 雷跃荣 +2 位作者 肖海燕 祖小涛 董会宁 《半导体光电》 EI CAS CSCD 北大核心 2008年第5期696-699,704,共5页
基于第一性原理的密度泛函理论,分析了覆盖度为1 ML(monolayer)的硫吸附在磷截止和镓截止的GaP(001)(1×2)表面的结构和电学属性。能量计算表明,最稳定的吸附模型均是SHB+ST4,镓和磷二聚物都被断开,周期单元由(1×2)变成(1×... 基于第一性原理的密度泛函理论,分析了覆盖度为1 ML(monolayer)的硫吸附在磷截止和镓截止的GaP(001)(1×2)表面的结构和电学属性。能量计算表明,最稳定的吸附模型均是SHB+ST4,镓和磷二聚物都被断开,周期单元由(1×2)变成(1×1),硫原子吸附在桥位置,Ga-S键比P-S键更稳定。电学性质分析可知,硫吸附在镓截止GaP表面后能隙中的表面态大幅度减少,而吸附在磷截止的表面时表面态并没有减少且在0.74 eV处多了一个新峰,硫吸附在镓截止表面后的态密度分布与实验结果吻合很好。因此,1 ML的硫吸附在GaP(001)面时表面上最主要形成Ga-S键。 展开更多
关键词 密度泛函理论 磷化镓 能带 态密度 功函变化
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Band gap calculation and photo catalytic activity of rare earths doped rutile TiO_2 被引量:13
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作者 边亮 宋绵新 +2 位作者 周天亮 赵效勇 戴清清 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第3期461-468,共8页
The density of states (DOS) of 17 kinds of rare earths (RE) doped rutile TiO2 was by using first-principles density functional theory (DFT) calculation. The band gap widths of RE doped futile TiO2 were important... The density of states (DOS) of 17 kinds of rare earths (RE) doped rutile TiO2 was by using first-principles density functional theory (DFT) calculation. The band gap widths of RE doped futile TiO2 were important factors for altering their absorbing wavelengths. The results show that RE ions could obviously reduce the band gap widths and form of energy of ruffle TiO2 except Lu, Y, Yb and Sc, and the order of absorbing wavelengths of RE doped ruffle TiO2 were the same as that of the results of calculation. The ratio of RE dopant was another important factor for the photo catalytic 'activity of RE doped rutile TiO2, and there was an optimal ratio of dopant. There was a constant for predigesting the calculation difficulty, respectively, which were 0.5mol.% and 100 mol^-1 under supposition. The band gap widths of RE doped rutile TiOz by DFT calculation were much larger than that by experiment. Finally, by transferring the calculation values to experiment values, it could be found and predicted that RE enlarged obviously the absorbing wavelengh of ruffle TiO2. In addition, the degree of RE ions edging out the Ti atom using the parameters of RE dements was computed. 展开更多
关键词 density functional theory ruffle TiO2 band gap rare earths
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The Gap Labelling Integrated Density of States for a Quasi Crystal Universe Is Identical to the Observed 4.5 Percent Ordinary Energy Density of the Cosmos 被引量:2
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作者 Mohamed S. El Naschie 《Natural Science》 2014年第16期1259-1265,共7页
Condense matter methods and mathematical models used in solving problems in solid state physics are transformed to high energy quantum cosmology in order to estimate the magnitude of the missing dark energy of the uni... Condense matter methods and mathematical models used in solving problems in solid state physics are transformed to high energy quantum cosmology in order to estimate the magnitude of the missing dark energy of the universe. Looking at the problem from this novel viewpoint was rewarded by a rather unexpected result, namely that the gap labelling method of integrated density of states for three dimensional icosahedral quasicrystals is identical to the previously measured and theoretically concluded ordinary energy density of the universe, namely a mere 4.5 percent of Einstein’s energy density, i.e. E(O) = mc2/22 where E is the energy, m is the mass and c is the speed of light. Consequently we conclude that the missing dark energy density must be E(D) = 1 - E(O) = mc2(21/22) in agreement with all known cosmological measurements and observations. This result could also be interpreted as a strong evidence for the self similarity of the geometry of spacetime, which is an expression of its basic fractal nature. 展开更多
关键词 E-INFINITY theory Fractal-Witten M-theory gap Labelling Theorem DENSITY of States Dark Energy DENSITY Noncommutative Geometry K-theory Dimension Group
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A study on relation between acoustic emission and characteristic displacement field on the sample with multi en echelon structures——The theoretic and experimental explorations of strain gap
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作者 陈顺云 许昭永 +5 位作者 杨润海 赵晋明 郝锦琦 王赟赟 熊秉衡 王正荣 《Acta Seismologica Sinica(English Edition)》 CSCD 2002年第6期656-666,共11页
Based on the phenomena that the deformation gap was observed before the great Tangshang earthquake, this paper discusses the strain gap according to test and theory. The (strain) patterns were recorded photographicall... Based on the phenomena that the deformation gap was observed before the great Tangshang earthquake, this paper discusses the strain gap according to test and theory. The (strain) patterns were recorded photographically by real-time holographic interferometry and shadow optical method of caustics, as soon as the loading process started. In the meantime, the AE (acoustic emission) signals were recorded by a micro crack information storage-analysis sys-tem. According to damage theory and location of micro fracture, we have studied the stain gap and gained: a) It is necessary that strain gap appears under the condition of linear elasticity theory, and its situation is relatively stable, corresponding to stress concentration. b) Micro fractures, which appear initially at area of high stress, occur rarely at the strain gap, and their locations are finally in the zone between the stress concentration area and the strain gap, which indicate the clusters or groups. However, the major macro fracture (final rupture) started from the shadow areas, and then grew quickly towards the strain gaps, which resulted in failure of sample. 展开更多
关键词 strain gap main fracture micro fracture damage theory
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Gap Equations and Effective Potentials at Finite Temperature and Chemical Potential in D—Dimensional Four—Fermion Models
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作者 ZHOUBang-Rong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第6期663-666,共4页
We have proven the general relations between the gap equations obeyed by dynamical fermion mass and thecorresponding effective potentials at finite temperature and chemical potential in D-dimensional four-fermion inte... We have proven the general relations between the gap equations obeyed by dynamical fermion mass and thecorresponding effective potentials at finite temperature and chemical potential in D-dimensional four-fermion interactionmodels. This gives an easy approach to get effective potentials directly from the gap equations. We find out explicitexpressions for the effective potentials at zero temperature in the cases of D = 2,3, and 4 for practical use. 展开更多
关键词 four-fermion model thermal field theory gap equation effective potential
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Ab-initio calculations of bandgap tuning of In1-xGaxY(Y=N,P)alloys for optoelectronic applications
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作者 Muhammad Rashid Jamil M +3 位作者 Mahmood Q Shahid M Ramay Asif Mahmood A Ghaithan H M 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第11期467-474,共8页
The III–V alloys and doping to tune the bandgap for solar cells and other optoelectronic devices has remained a hot topic of research for the last few decades.In the present article,the bandgap tuning and its influen... The III–V alloys and doping to tune the bandgap for solar cells and other optoelectronic devices has remained a hot topic of research for the last few decades.In the present article,the bandgap tuning and its influence on optical properties of In1-xGaxN/P,where(x=0.0,0.25,0.50,0.75,and 1.0)alloys are comprehensively analyzed by density functional theory based on full-potential linearized augmented plane wave method(FP-LAPW)and modified Becke and Johnson potentials(TB-mBJ).The direct bandgaps turn from 0.7 eV to 3.44 eV,and 1.41 eV to 2.32 eV for In1-xGaxN/P alloys,which increases their potentials for optoelectronic devices.The optical properties are discussed such as dielectric constants,refraction,absorption,optical conductivity,and reflection.The light is polarized in the low energy region with minimum reflection.The absorption and optical conduction are maxima in the visible region,and they are shifted into the ultraviolet region by Ga doping.Moreover,static dielectric constant e1(0)is in line with the bandgap from Penn’s model. 展开更多
关键词 density functional theory direct bandgap III-V semiconductors tuning of optical band gap solar cell applications
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基于Info-Gap的重力式挡土墙的鲁棒性分析
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作者 崔亚军 王法军 +2 位作者 贺鹏 郑程程 王凤举 《岩土工程技术》 2020年第4期211-216,共6页
由于岩土力学参数的变异性及其数据信息获取的有限性,致使现有重力式挡土墙稳定性的不确定性分析方法难以反映其真实的安全性能和失效水平。拟在现有重力式挡土墙稳定性分析方法中引入Information-Gap(Info-Gap)理论,通过分析不确定参... 由于岩土力学参数的变异性及其数据信息获取的有限性,致使现有重力式挡土墙稳定性的不确定性分析方法难以反映其真实的安全性能和失效水平。拟在现有重力式挡土墙稳定性分析方法中引入Information-Gap(Info-Gap)理论,通过分析不确定参量允许不确定性程度的变化幅值及其度量方法,建立重力式挡土墙稳定性的不确定性分析的鲁棒可靠度评价模型;基于重力式挡土墙功能输出响应模型,利用区间组合法确定相应的鲁棒可靠度指标,进而建立了基于Info-Gap理论的重力式挡土墙鲁棒性设计方法。为了验证所提出的鲁棒性分析方法的有效性和重要性,结合某工程实例加以说明。在鲁棒性设计方法和可靠性设计方法的基础上对该设计进行了比较研究。该方法为因缺乏足够数据样本和信息量的工程问题的不确定性分析提供了新的途径。 展开更多
关键词 重力式挡土墙稳定性 Info-gap理论 不确定性分析 鲁棒可靠度指标
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