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Upsilon Constants and Their Usefulness in Planck Scale Quantum Cosmology
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2024年第2期167-173,共7页
This paper introduces the two Upsilon constants to the reader. Their usefulness is described with respect to acting as coupling constants between the CMB temperature and the Hubble constant. In addition, this paper su... This paper introduces the two Upsilon constants to the reader. Their usefulness is described with respect to acting as coupling constants between the CMB temperature and the Hubble constant. In addition, this paper summarizes the current state of quantum cosmology with respect to the Flat Space Cosmology (FSC) model. Although the FSC quantum cosmology formulae were published in 2018, they are only rearrangements and substitutions of the other assumptions into the original FSC Hubble temperature formula. In a real sense, this temperature formula was the first quantum cosmology formula developed since Hawking’s black hole temperature formula. A recent development in the last month proves that the FSC Hubble temperature formula can be derived from the Stephan-Boltzmann law. Thus, this Hubble temperature formula effectively unites some quantum developments with the general relativity model inherent in FSC. More progress towards unification in the near-future is expected. 展开更多
关键词 Quantum Cosmology Hubble Constant Planck Scale Upsilon Constant Flat Space Cosmology Black Holes CMB Temperature ΛCDM Cosmology Quantum Gravity Unification
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Effects of initial δ phase(Ni_3Nb) on hot tensile deformation behaviors and material constants of Ni-based superalloy 被引量:8
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作者 蔺永诚 何敏 +2 位作者 陈明松 温东旭 陈荐 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第1期107-117,共11页
Effects of initial δ phase(Ni_3Nb) on the hot tensile deformation behaviors and material constants of a Ni-based superalloy were investigated over wide ranges of strain rate and deformation temperature. It is found... Effects of initial δ phase(Ni_3Nb) on the hot tensile deformation behaviors and material constants of a Ni-based superalloy were investigated over wide ranges of strain rate and deformation temperature. It is found that the true stress-true strain curves exhibit peak stress at a small strain, and the peak stress increases with the increase of initial δ phase. After the peak stress, initial δ phase promotes the dynamic softening behaviors, resulting in the decreased flow stress. An improved Arrhenius constitutive model is proposed to consider the synthetical effects of initial δ phase, deformation temperature, strain rate, and strain on hot deformation behaviors. In the improved model, material constants are expressed as the functions of the content of initial δ phase and strain. A good agreement between the predicted and measured results indicates that the improved Arrhenius constitutive model can well describe hot deformation behaviors of the studied Ni-based superalloy. 展开更多
关键词 Ni-based superalloy hot deformation initial δ phase constitutive model material constants
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Biaxial tensile properties and elastic constants evaluation of envelope material for airship 被引量:1
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作者 陈建稳 陈务军 《Journal of Southeast University(English Edition)》 EI CAS 2014年第4期467-474,共8页
This paper presents an experimental study to determine the tensile properties of the envelope fabric Uretek3216L under biaxial cyclic loading.First the biaxial cyclic tests were carefully carried out on the envelope m... This paper presents an experimental study to determine the tensile properties of the envelope fabric Uretek3216L under biaxial cyclic loading.First the biaxial cyclic tests were carefully carried out on the envelope material to obtain the stress-strain data and the corresponding nonlinearity and orthotropy of the material were analyzed. Then for some determination options with different stress ratios the least squares method minimizing the strain terms was used to calculate the elastic constants from the experimental data.Finally the influences of the determination options with different stress ratios and the reciprocal relationship on the elastic constants were discussed.Results show that the orthotropy of the envelope material can be attributed to the unbalanced crimp of their constitutive yarns in warp and weft directions and the elastic constants vary noticeably with the determination options as well as the normalized stress ratios.In real design practice it is more reasonable to use constants determined for specific stress states in particular stress ratios depending on the project&#39;s needs.Also calculating the structures with two limitative sets of elastic constants instead of using only one set is recommendable in light of the great variety of the constant&#39;s values. 展开更多
关键词 coated fabric AIRSHIP tensile property reciprocal relationship elastic constant stress ratio
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FeCoRE磁交换常数第一性原理计算和居里温度提高机制研究
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作者 李志伟 朱颖丽 +2 位作者 罗港涛 陈平安 李享成 《原子与分子物理学报》 CAS 北大核心 2025年第4期156-162,共7页
信息通讯和军事电子技术发展对磁性材料的高温磁性提出了越来越高的要求,研究高温环境下高效稳定工作的磁性材料具有重要意义.本文结合第一性原理和蒙特卡洛方法,研究了Fe、Co比例和稀土元素(Gd、Tb、Dy)掺杂对合金FeCo晶体结构、磁交... 信息通讯和军事电子技术发展对磁性材料的高温磁性提出了越来越高的要求,研究高温环境下高效稳定工作的磁性材料具有重要意义.本文结合第一性原理和蒙特卡洛方法,研究了Fe、Co比例和稀土元素(Gd、Tb、Dy)掺杂对合金FeCo晶体结构、磁交换常数和高温磁性的影响.结果表明随着Co含量增加,合金晶体结构从体心立方向简单和面心立方转变,当Co含量为50%时,Fe-Co键长最短,最近邻磁交换常数从18.05 meV增加到30.03 meV,使FeCo的居里温度提高到1580 K,相比于Fe的居里温度增幅达到60%.将稀土元素掺入FeCo体系后,发现3.125%含量Er、Dy、Tb的掺杂对合金FeCo居里温度分别有60K、45K和20K的提高,电子构型重构导致强的稀土元素与Fe和Co之间的交换作用是居里温度提升的主要原因. 展开更多
关键词 高温磁性 第一性原理 蒙特卡洛 磁交换常数
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Experimental Determination of the Vibrational Constants of FeS(X5 △) by Dispersed Fluorescence Spectroscopy
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作者 王莉 黄道菱 +2 位作者 甄军锋 张群 陈旸 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第1期1-3,I0003,共4页
Based on previous laser-induced fluorescence excitation spectroscopy work, the vibrational constants of neutral FeS in the X5 △ electronic state were obtained by directly mapping the ground-state vibrational levels u... Based on previous laser-induced fluorescence excitation spectroscopy work, the vibrational constants of neutral FeS in the X5 △ electronic state were obtained by directly mapping the ground-state vibrational levels up to v"=3 using conventional laser-induced dispersed fluorescence spectroscopy. The vibrational frequency of FeS(X5 △) (518±5 cm-1) agrees well with that reported in a recent PES measurement (520±30 cm-1) [J. Phys. Chem. A 107, 2821 (2003)] which is the only one prior experimental vibrational frequency value for the 5 △ state of FeS. Careful comparisons of our experimental results and those documented in the literature (mainly from theoretical predictions) suggest that the ground state of FeS is 5 △ state. 展开更多
关键词 FES Vibrational constant Laser-induced dispersed fluorescence spectroscopy
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Determination of Stability Constants of Cadmium-Glycine Complexes by a Unified Treatment for Potentiometric and Polarographic Data
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作者 张建民 石秋芝 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第2期164-168,共5页
The cadmium(Ⅱ)-glycine system was studied by the two experimental techniques, ion sensitive electrode (ISE) and differential pulse polarography (DPP), and the experimental data obtained were used by a unified m... The cadmium(Ⅱ)-glycine system was studied by the two experimental techniques, ion sensitive electrode (ISE) and differential pulse polarography (DPP), and the experimental data obtained were used by a unified mathematical treatment to calculate the complex stability constants. The combination of the two techniques is of many advantages as ISE can be performed at low [LT]:[MT] ratios and significantly higher [MT], whereas DPP could be used well at large [LT]:[MT] ratios and much smaller [MT]. This makes it possible to study a metal-ligand system in a relatively broader range of experimental conditions that, in turn, provides more information about the metakligand system of interest. Applying the unified mathematical treatment to the cadmium-glycine system, two new complexes MHL and ML2(OH) as well as three complexes ML, ML2 and ML3, reported in literatures, could be modeled and all their stability constants have been refined. 展开更多
关键词 Metal complex POLAROGRAPHY POTENTIOMETRY Stability constant
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Dual laterolog borehole correction based on dynamic tool constants
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作者 王欣 陈浩 王秀明 《Applied Geophysics》 SCIE CSCD 2012年第4期414-420,495,共8页
The positive and negative difference of deep and shallow resisitivity in formation without invasion is caused mainly by the fixed two tool constants from numerical simulations. A dynamic calibration method for tool co... The positive and negative difference of deep and shallow resisitivity in formation without invasion is caused mainly by the fixed two tool constants from numerical simulations. A dynamic calibration method for tool constants is proposed based on the effects of the mud and formation resisitivity ratio on the two constants calculated using the finite element method (FEM). Finally, four specific examples are given to validate the dynamic calibration method. It is an automatic borehole correction method and can give more accurate formation resistivity. The method is useful for dual laterolog logging. 展开更多
关键词 Dual laterolog positive and negative differences tool constants dynamic calibration
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DDI METHOD FOR MEASURING OPTICAL CONSTANTS OF THIN FILMS
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作者 谷晋骐 郑永星 《Transactions of Tianjin University》 EI CAS 1997年第1期93-96,共4页
By double beam and double wave interferomatric (DDI) method, the optical constants of thin films, i.e. refractive index, extinction coefficient and thickness may be determined in infrared (3.39 μm) and in visible (... By double beam and double wave interferomatric (DDI) method, the optical constants of thin films, i.e. refractive index, extinction coefficient and thickness may be determined in infrared (3.39 μm) and in visible (0.633 μm) wavelengths in the same optical path with a tunable double wave He Ne laser designed by ourselves. The measuring principle and the device are describod. 展开更多
关键词 DDI thin film optical constant
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RALE评分系统在血液肿瘤并发急性呼吸窘迫综合征患儿中的应用 被引量:3
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作者 雷嘉颖 祝铃萍 +4 位作者 戴振源 苏若男 麦友刚 陈壮桂 汤昔康 《解放军医学杂志》 CAS CSCD 北大核心 2020年第2期133-138,共6页
目的探讨RALE评分系统对血液肿瘤患儿并发急性呼吸窘迫综合征(ARDS)的评估价值。方法回顾性分析2014年1月-2018年6月中山大学孙逸仙纪念医院儿科重症监护病房收治的57例血液肿瘤并发ARDS患儿的临床资料,根据28 d内死亡情况分为存活组(n=... 目的探讨RALE评分系统对血液肿瘤患儿并发急性呼吸窘迫综合征(ARDS)的评估价值。方法回顾性分析2014年1月-2018年6月中山大学孙逸仙纪念医院儿科重症监护病房收治的57例血液肿瘤并发ARDS患儿的临床资料,根据28 d内死亡情况分为存活组(n=23)及死亡组(n=34)。比较两组患儿的临床特征,同时分析RALE评分与氧合指数(PaO2/FiO2,P/F值)的相关性以及RALE评分对ARDS患儿生存预后的评估价值。结果死亡组第1天的氧合指数(D1P/F值)低于存活组[116.0(70.0,192.0)vs.189.5(136.5,251.3)],而死亡组第1天的儿童死亡风险Ⅲ(D1 PRISMⅢ)[10.0(8.0,16.0)vs.7.6(4.0,13.4)]、D1 RALE评分[27.0(25.0,37.0)vs.24.0(13.8,35.3)]及D3-D1 RALE评分差值[5(0,8)vs.–3.5(–7,1)]均高于存活组;D1 RALE评分与D1 P/F值呈负相关(r=–0.831,P<0.001);D3-D1 RALE评分差值大是患儿28 d内死亡的独立危险因素;D1 RALE评分≤23分及D3-D1 RALE评分差值≤–3分的患儿28 d存活率较高。结论RALE评分可反映ARDS的氧合状况,并对危险分层具有一定作用,有助于筛选出高危患者。 展开更多
关键词 rale评分 血液肿瘤 儿童 急性呼吸窘迫综合征
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石墨烯褶皱结构对双电层储能性能的理论研究
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作者 张倩 蒋更平 《原子与分子物理学报》 CAS 北大核心 2025年第6期89-100,共12页
石墨烯因其出色的比表面积和单层结构而被广泛认为是一种理想的电极材料.然而,实验制备的石墨烯常因官能团、缺陷和位错的引入而出现褶皱和变形.针对这一问题,本文构建了一系列具有不同幅度褶皱(a=0~6.6?)的石墨烯片,并运用分子动力学... 石墨烯因其出色的比表面积和单层结构而被广泛认为是一种理想的电极材料.然而,实验制备的石墨烯常因官能团、缺陷和位错的引入而出现褶皱和变形.针对这一问题,本文构建了一系列具有不同幅度褶皱(a=0~6.6?)的石墨烯片,并运用分子动力学模拟来研究这些褶皱石墨烯表面的双电层结构.本研究旨在探讨不同褶皱高度和充电状态下双电层的变化规律,及其与超级电容器储能性能之间的关系.研究发现,褶皱石墨烯模型内部的离子浓度随电压的增加呈现多峰层状分布,而表面离子浓度与施加的电压正相关.此外,石墨烯的褶皱结构能够减少离子和水对电极电压响应的敏感性.在不同电压条件下,褶皱型石墨烯结构的面积比电容(C_A)始终高于其平面对应区域,突出了其在提升双电层储能性能上的优势.本研究揭示了石墨烯褶皱结构在调节离子分布、降低电压敏感性,以及增强电化学储能性能方面的特有作用机制. 展开更多
关键词 双电层 石墨烯 褶皱 恒电势模拟方法
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Effect of lens constants optimization on the accuracy of intraocular lens power calculation formulas for highly myopic eyes 被引量:6
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作者 Jia-Qing Zhang Xu-Yuan Zou +3 位作者 Dan-Ying Zheng Wei-Rong Chen Ao Sun Li-Xia Luo 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第6期943-948,共6页
AIM: To evaluate the effect of different lens constant optimization methods on the accuracy of intraocular lens(IOL) power calculation formulas for highly myopic eyes.METHODS: This study comprised 108 eyes of 94 conse... AIM: To evaluate the effect of different lens constant optimization methods on the accuracy of intraocular lens(IOL) power calculation formulas for highly myopic eyes.METHODS: This study comprised 108 eyes of 94 consecutive patients with axial length(AL) over 26 mm undergoing phacoemulsification and implantation of a Rayner(Hove, UK) 920H IOL. Formulas were evaluated using the following lens constants: manufacturer’s lens constant, User Group for Laser Interference Biometry(ULIB) constant, and optimized constant for long eyes. Results were compared with Barrett Universal II formula, original Wang-Koch AL adjustment method, and modified Wang-Koch AL adjustment method. The outcomes assessed were mean absolute error(MAE) and percentage of eyes with IOL prediction errors within ±0.25, ±0.50, and ±1.0 diopter(D). The nonparametric method, Friedman test, was used to compare MAE performance among constants.RESULTS: Optimized constants could significantly reduce the MAE of SRK/T, Hoffer Q, and Holladay 1 formulas compared with manufacturer’s lens constant, whereas the percentage of eyes with IOL prediction errors within ±0.25, ±0.50, and ±1.0 D had no statistically significant differences. Optimized lens constant for long eyes alone showed non-significant refractive advantages over the ULIB constant. Barrett Universal II formula and formulas with AL adjustment showed significantly higher accuracy in highly myopic eyes(P<0.001). CONCLUSION: Lens constant optimization for the subset of long eyes reduces the refractive error only to a limited extent for highly myopic eyes. 展开更多
关键词 high MYOPIA CATARACT INTRAOCULAR LENS power LENS constant OPTIMIZATION prediction error
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Binding Constants for Terbium(Ⅲ) with Chicken Apoovotransferrin 被引量:3
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作者 YANG Bin sheng LI Ying qi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2001年第1期6-13,共8页
The binding of Tb 3+ to chicken apoovotransferrin was studied by monitoring the fluorescent intensity of Tb 3+ at 549 nm. The conditional equilibrium constants for the complexation of Tb 3+ by chicken apoovotransferri... The binding of Tb 3+ to chicken apoovotransferrin was studied by monitoring the fluorescent intensity of Tb 3+ at 549 nm. The conditional equilibrium constants for the complexation of Tb 3+ by chicken apoovotransferrin in 0 1 mol/L hepes, at pH 7 4 and room temperature were measured. The successive macroscopic binding constants are lg K 1=9 08±0 12 and lg K 2=7 36±0 22. The molar fluorescence enhancement of Tb 3+ apoovotransferrin complex is (2 06±0 14)×10 4 mol -1 ·L. The fluorescence quenching experiment and the titration of N terminal monoferric ovotransferrin showed that Tb 3+ has a preference for being bound to the N terminal binding site of apoovotransferrin. 展开更多
关键词 TERBIUM TRANSFERRIN Binding constant FLUORESCENCE
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Investigations on spectroscopic parameters, vibrational levels, classical turning points and inertial rotation and centrifugal distortion constants for the 1 + X^1∑g^+ state of sodium dimer 被引量:4
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作者 余本海 戴启润 +1 位作者 施德恒 刘玉芳 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第10期2962-2967,共6页
The density functional theory (B3LYP, B3P86) and the quadratic configuration-interaction method including single and double substitutions (QCISD(T), QCISD) presented in Gaussian03 program package are employed to... The density functional theory (B3LYP, B3P86) and the quadratic configuration-interaction method including single and double substitutions (QCISD(T), QCISD) presented in Gaussian03 program package are employed to calculate the equilibrium internuclear distance Re, the dissociation energy De and the harmonic frequency We for the XIEg+ state of sodium dimer in a number of basis sets. The conclusion is gained that the best Re, De and We results can be attained at the QCISD/6-311G(3df,3pd) level of theory. The potential energy curve at this level of theory for this state is obtained over a wide internuclear separation range from 0.16 to 2.0 nm and is fitted to the analytic Murrell-Sorbie function. The spectroscopic parameters De, DO, Re, ωe, ωe Xe, αe and Be are calculated to be 0.7219 eV, 0.7135 eV, 0.31813 nm, 151.63 cm^-1, 0.7288 cm^-1, 0.000729 cm^-1 and 0.1449 cm^-1, respectively, which are in good agreement with the measurements. With the potential obtained at the QCISD/6-311G(3df,3pd) level of theory, a total of 63 vibrational states is found when J = 0 by solving the radial SchrSdinger equation of nuclear motion. The vibrational level, corresponding classical turning point and inertial rotation constant are computed for each vibrational state. The centrifugal distortion constants (Dr Hv, Lv, Mv, Nv and Ov) are reported for the first time for the first 31 vibrational states when J = 0. 展开更多
关键词 dissociation energy vibrational level turning point centrifugal distortion constant
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Valence Bond Study of Dissociation Behavior and Spectroscopic Constants for the Ground States of LiF and NaF 被引量:3
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作者 CAO Ze-xing WU Wei ZHANG Qian-er 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1998年第3期75-81,共7页
Ab initio VB calculations were used to determine the accurate spectroscopic parameters of the ground states of LiF and NaF. A set of potential energy curves corresponding to the ground states including ionic and cov... Ab initio VB calculations were used to determine the accurate spectroscopic parameters of the ground states of LiF and NaF. A set of potential energy curves corresponding to the ground states including ionic and covalent interactions, pure ionic interaction and covalent interaction were generated using the VBSCF method. Curve crossing in the dissociation processes of LiF and NaF was discussed. The optimized VB wave functions suggest that LiF and NaF are of high ionicity, and their ionic weights are 86 2% and 94 6%, respectively. NaF has a higher ionicity. The main difference between atom F and ion F - and the effect of the proper description of this difference on dissociation energies were investigated. 展开更多
关键词 VBSCF Spectroscopic constant Curve crossing
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Thickness dependence of the optical constants of oxidized copper thin films based on ellipsometry and transmittance 被引量:2
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作者 宫俊波 董伟乐 +3 位作者 代如成 王中平 张增明 丁泽军 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第8期112-116,共5页
Thin oxidized copper films in various thickness values are deposited onto quartz glass substrates by electron beam evaporation. The ellipsometry parameters and transmittance in a wavelength range of 300 nm-1000 nm are... Thin oxidized copper films in various thickness values are deposited onto quartz glass substrates by electron beam evaporation. The ellipsometry parameters and transmittance in a wavelength range of 300 nm-1000 nm are collected by a spectroscopic ellipsometer and a spectrophotometer respectively. The effective thickness and optical constants, i.e., refractive index n and extinction coefficient k, are accurately determined by using newly developed ellipsometry combined with transmittance iteration method. It is found that the effective thickness determined by this method is close to the physical thickness and has obvious difference from the mass thickness for very thin film due to variable density of film. Furthermore, the thickness dependence of optical constants of thin oxidized Cu films is analyzed. 展开更多
关键词 thin film optical constants thickness COPPER
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Third-order elastic, piezoelectric, and dielectric constants 被引量:1
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作者 Yanming ZHANG Jun JIN Hongping HU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2019年第12期1831-1846,共16页
The definitions of the third-order elastic,piezoelectric,and dielectric constants and the properties of the associated tensors are discussed.Based on the energy conservation and coordinate transformation,the relations... The definitions of the third-order elastic,piezoelectric,and dielectric constants and the properties of the associated tensors are discussed.Based on the energy conservation and coordinate transformation,the relations among the third-order constants are obtained.Furthermore,the relations among the third-order elastic,piezoelectric,and dielectric constants of the seven crystal systems and isotropic materials are listed in detail.These third-order constants relations play an important role in solving nonlinear problems of elastic and piezoelectric materials.It is further found that all third-order piezoelectric constants are 0 for 15 kinds of point groups,while all third-order dielectric constants are 0 for 16 kinds of point groups as well as isotropic material.The reason is that some of the point groups are centrally symmetric,and the other point groups are high symmetry.These results provide the foundation to measure these constants,to choose material,and to research nonlinear problems.Moreover,these results are helpful not only for the study of nonlinear elastic and piezoelectric problems,but also for the research on flexoelectric effects and size effects. 展开更多
关键词 THIRD-ORDER ELASTIC CONSTANT THIRD-ORDER PIEZOELECTRIC CONSTANT nonlinear THIRD-ORDER dielectric CONSTANT crystal COORDINATE transformation TENSOR
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Effective electroelastic constants for three-phase confocal elliptical cylinder model in piezoelectric quasicrystal composites 被引量:5
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作者 Yongbin WANG Junhong GUO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2018年第6期797-812,共16页
A three-phase confocal elliptical cylinder model is proposed to analyze micromechanics of one-dimensional hexagonal piezoelectric quasicrystal (PQC) compos- ites. Exact solutions of the phonon, phason, and electric ... A three-phase confocal elliptical cylinder model is proposed to analyze micromechanics of one-dimensional hexagonal piezoelectric quasicrystal (PQC) compos- ites. Exact solutions of the phonon, phason, and electric fields are obtained by using the conformal mapping combined with the Laurent expansion technique when the model is subject to far-field anti-plane mechanical and in-plane electric loadings. The effective elec- troelastic constants of several different composites made up of PQC, quasicrystal (QC), and piezoelectric (PE) materials are predicted by the generalized self-consistent method. Numerical examples are conducted to show the effects of the volume fraction and the cross-sectional shape of inclusion (or fiber) on the effective electroelastic constants of these composites. Compared with other micromechanical methods, the generalized self- consistent and Mori-Tanaka methods can predict the effective electroelastic constants of the composites consistently. 展开更多
关键词 piezoelectric quasicrystal (PQC) three-phase elliptical cylinder model effective constant generalized self-consistent method
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A Comparative Study of Elastic Constants of NiTi and NiAl Alloys from First-Principle Calculations 被引量:2
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作者 Jianmin Lu Qingmiao Hu Rui Yang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2009年第2期215-218,共4页
To investigate the origin of the strong dependence of martensitic transformation temperature on composition, the elastic properties of high temperature B2 phases of both NiTi and NiAI were calculated by a first-princi... To investigate the origin of the strong dependence of martensitic transformation temperature on composition, the elastic properties of high temperature B2 phases of both NiTi and NiAI were calculated by a first-principle method, the exact-muffin orbital method within coherent potential approximation. In the composition range of 50-56 at. pct Ni of NiTi and 60-70 at. pct Ni of NiAI in which martensitic transformation occurs, non-basalplane shear modulus c44 increases with increasing Ni content, while basal-plane shear modulus c' decreases. In the above composition ranges however the transformation temperature of NiAI increases with increasing Ni content while that of NiTi decreases from experimental observation. The softening of c' is experimentally observed only in NiAI, and the decrease of c' with increasing Ni content is responsible for the increase of transformation temperature. The result of the present work demonstrates that, besides c', c44 also influences the martensitic transformation of NiTi and plays quite important a role. 展开更多
关键词 NITI NiA1 Elastic constant First-principle calculation
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The Determination of the Protonation Constants of A New Macrocyclic Dinucleating Ligand, BDBPH 被引量:2
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作者 Guo Qiang SHANGGUAN Ning WANG +1 位作者 Hong En WANG Arthur EMARTELL 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第2期171-174,共4页
The protonation constants of a new dinucleating 24-membered hexaazadiphenol macrocyclic ligand, BDBPH, were determined by potentiometric measurement at 25.0 degreesC and mu = 0.100 mol.L-1 (KCl). The species distribut... The protonation constants of a new dinucleating 24-membered hexaazadiphenol macrocyclic ligand, BDBPH, were determined by potentiometric measurement at 25.0 degreesC and mu = 0.100 mol.L-1 (KCl). The species distributions of the deprotonated and protonated compounds in the pH range from 2 to 12 aqueous solutions were also described. 展开更多
关键词 Protonation constant potentiometric measurement macrocyclic ligand
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Proton radiation effects on optical constants of Al film reflector 被引量:2
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作者 刘海 魏强 +1 位作者 何世禹 赵丹 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第5期1086-1089,共4页
The Al film reflectors can yield a high-reflectance over a broad wavelength region, and have been widely used in the spacecraft optical instruments for high quality optical applications. Under the irradiation of charg... The Al film reflectors can yield a high-reflectance over a broad wavelength region, and have been widely used in the spacecraft optical instruments for high quality optical applications. Under the irradiation of charged particles in the Earth radiation belt, the reflectors could be deteriorated. In order to reveal the deterioration mechanism, the change in optical constants of Al film reflector induced by proton radiation with 60 keV was studied in an environment of vacuum with heat sink. Experimental results showed that when the radiation damage primarily occurs in the Al reflecting film, the extinction coefficient k will gradually decrease with increasing radiation fluence, which results in the decrease of the energies of reflective light. Therefore, the proton radiation induced an obvious degradation of spectral reflectance in the wavelength region from 200 to 800nm on the Al film reflector. 展开更多
关键词 Al film reflector optical constants radiation damage
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