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A simple semiempirical model for the static polarizability of ions
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作者 Alexander S Sharipov Boris I Loukhovitski 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第8期32-45,共14页
A concise analytical model for the static dipole polarizability of ionized atoms and molecules is created for the first time.As input,it requires,alongside the polarizability of neutral counterpart of a given ion,only... A concise analytical model for the static dipole polarizability of ionized atoms and molecules is created for the first time.As input,it requires,alongside the polarizability of neutral counterpart of a given ion,only the charge and elemental composition.This physically motivated semiempirical model is based on a number of established regularities in polarizability of charged monatomic and polyatomic compounds.In order to adjust it,the results of quantum chemistry calculations and gas-phase measurements available for a broad range of ionized multielectron species are employed.To counteract the appreciable bias in the literature data toward polarizability of monoatomic ions,for some molecular ions of general concern the results of the authors'own density functional theory calculations are additionally invoked.A total of 541 data points are used to optimize the model.It is demonstrated that the model we suggested has reasonable(given the substantial uncertainties of the reference data)accuracy in predicting the static isotropic polarizability of arbitrarily charged ions of any size and atomic composition.The resulting polarizability estimates are found to achieve a coefficient of determination of 0.93 for the assembled data set.The created analytic tool is universally applicable and might be advantageous for some applications where there is an urgent need for rapid low-cost evaluation of the static gas-phase polarizability of ionized atoms and molecules.This is especially relevant to constructing the complex models of nonequilibrium chemical kinetics aimed at precisely describing the observable refractive index(dielectric permittivity)of plasma flows.The data sets that support the findings of this study are openly available in Science Data Bank at https://doi.org/10.57760/sciencedb.07526. 展开更多
关键词 polarizability IONS semiempirical model quantum chemistry
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A simple semiempirical model for the static polarizability of electronically excited atoms and molecules
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作者 Alexander S Sharipov Alexey V Pelevkin Boris I Loukhovitski 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期290-301,共12页
We present a semiempirical analytical model for the static polarizability of electronically excited atoms and molecules,which requires very few readily accessible input data,including the ground-state polarizability,e... We present a semiempirical analytical model for the static polarizability of electronically excited atoms and molecules,which requires very few readily accessible input data,including the ground-state polarizability,elemental composition,ionization potential,and spin multiplicities of excited and ground states.This very simple model formulated in a semiclassical framework is based on a number of observed trends in polarizability of electronically excited compounds.To adjust the model,both accurate theoretical predictions and reliable measurements previously reported elsewhere for a broad range of multielectron species in the gas phase are utilized.For some representative compounds of general concern that have not yet attracted sufficient research interest,the results of our multireference second-order perturbation theory calculations are additionally engaged.We show that the model we developed has reasonable(given the considerable uncertainties in the reference data)accuracy in predicting the static polarizability of electronically excited species of arbitrary size and excitation energy.These findings can be useful for many applications,where there is a need for inexpensive and quick assessments of the static gas-phase polarizability of excited electronic states,in particular,when building the complex nonequilibrium kinetic models to describe the observed optical refractivity(dielectric permittivity)of nonthermal reacting gas flows. 展开更多
关键词 polarizability electronic excitation semiempirical model quantum chemistry
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基于密度泛函理论对团簇CrPS_(4)的光谱分析 被引量:2
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作者 方志刚 刘立娥 +3 位作者 吴庭慧 宋静丽 原琳 魏代霞 《贵州师范大学学报(自然科学版)》 CAS 北大核心 2024年第3期1-8,共8页
为快速、高效得到物质的谱图数据,利用计算化学方法,根据拓扑学原理,利用密度泛函理论,对团簇CrPS_(4)10种优化构型的红外光谱、拉曼光谱、偶极矩以及极化率进行了分析,并利用构型2^((4))的理论红外谱图与前人所得实际光谱图进行了对比... 为快速、高效得到物质的谱图数据,利用计算化学方法,根据拓扑学原理,利用密度泛函理论,对团簇CrPS_(4)10种优化构型的红外光谱、拉曼光谱、偶极矩以及极化率进行了分析,并利用构型2^((4))的理论红外谱图与前人所得实际光谱图进行了对比。结果显示:CrPS_(4)红外光谱的波峰大致分布在300~700 cm^(-1)范围内,拉曼光谱的波峰范围主要分布在200~700 cm^(-1)范围内;团簇CrPS_(4)振动形式为伸缩振动时,其对入射光的吸收强度较大;在频率较低的波段,CrPS_(4)更易发生红外吸收,在频率较高的波段,更易发生拉曼散射;总偶极矩的排列顺序为2^((2))>6^((4))>4^((2))>3^((2))>3^((4))>4^((4))>1^((2))>2^((4))>5^((4))>1^((4)),偶极矩越大,红外活性越强;极化率大小关系满足5^((4))<1^((4))<6^((4))<4^((4))<3^((4))<1^((2))<2^((4))<2^((2))<3^((2))<4^((2)),极化率越大,拉曼活性越强;所有构型的3大主轴中,XX轴的极化率均大于YY轴与ZZ轴;构型2^((4))的理论光谱图与实际结果对比发现,两者光谱图波峰频率基本吻合,实验与理论分析互为补充。 展开更多
关键词 光谱 密度泛函理论 红外光谱 拉曼光谱 极化率 偶极矩
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基于斯卡那维模型的离子晶体介电性能的研究
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作者 罗昊 成鹏飞 +4 位作者 党子妍 耿可佳 孔存存 秦新瑞 苏耀恒 《人工晶体学报》 CAS 北大核心 2024年第6期991-998,共8页
本文采用玻恩圆周轨道极化模型、双原子分子离子位移极化模型,分别计算了NaCl晶体中各离子的电子位移极化率和离子位移极化率。进一步采用点偶极子近似和双原子分子平均场近似,考虑在极化离子所产生的附加电场的作用下,基于斯卡那维模... 本文采用玻恩圆周轨道极化模型、双原子分子离子位移极化模型,分别计算了NaCl晶体中各离子的电子位移极化率和离子位移极化率。进一步采用点偶极子近似和双原子分子平均场近似,考虑在极化离子所产生的附加电场的作用下,基于斯卡那维模型计算出包含不同离子数目的NaCl晶体的有效电场结构系数,得到了与实测值更为接近的介电常数,与将晶体内部的有效电场视为外施宏观平均电场的Born理论计算值进行对比,误差值从11.4%降至4.3%。研究结果提供了通过斯卡那维模型精确计算离子晶体介电性能的新思路。 展开更多
关键词 NACL晶体 电子位移极化率 离子位移极化率 有效电场结构系数 介电常数 斯卡那维模型
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团簇FePS_(3)的极化率及催化性质研究
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作者 魏代霞 方志刚 +3 位作者 宋静丽 吴庭慧 刘立娥 原琳 《江西师范大学学报(自然科学版)》 CAS 北大核心 2024年第1期75-82,共8页
为探究团簇FePS_(3)各优化构型内部电子在受外电场影响时的变化情况及其催化性质,运用密度泛函理论的B3LYP杂化泛函方法,并使用def2-tzvp基组对设计出的几何构型进行全参数优化和频率计算,共得到在二、四重态下的12种优化构型.从各构型... 为探究团簇FePS_(3)各优化构型内部电子在受外电场影响时的变化情况及其催化性质,运用密度泛函理论的B3LYP杂化泛函方法,并使用def2-tzvp基组对设计出的几何构型进行全参数优化和频率计算,共得到在二、四重态下的12种优化构型.从各构型的极化率、能隙差、态密度图、HOMO和LUMO轨道图以及反应活性参数分析发现:构型1^((2))的极化率和极化率各向异性不变量均最大,易受外电场影响且容易发生形变.构型4^((4))和2^((2))对外电场响应能力较弱且结构最紧凑,不易发生形变.构型6^((2))的能隙差最小,电子跃迁最容易,并且该构型的第1电离能相对较小,电子亲和能、电负性和亲电指数均相对较大,催化活性最强.分析比较态密度图和HOMO、LUMO轨道图发现:团簇FePS_(3)的失电子能力强于其得电子能力,且S原子对团簇HOMO轨道和LUMO轨道的贡献大于P、Fe原子,这表明团簇FePS_(3)的催化活性主要由S原子贡献,但是P、Fe原子的贡献作用亦不可忽视. 展开更多
关键词 团簇FePS_(3) 密度泛函理论 极化率 能隙差 反应活性
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Al^(+)光钟态“幻零”波长的理论计算
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作者 魏远飞 唐志明 +1 位作者 李承斌 黄学人 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第10期96-104,共9页
本文使用组态相互作用加多体微扰理论方法对Al^(+)光钟态3s^(2)^(1)S_(0)和3s3p^(3)P_(0)的“幻零”波长进行了理论计算.3s^(2)^(1)S_(0)态的“幻零”波长为266.994(1)nm,3s3p^(3)P_(0)态的“幻零”波长为184.56(7)nm,174.4(1)nm,121.5(... 本文使用组态相互作用加多体微扰理论方法对Al^(+)光钟态3s^(2)^(1)S_(0)和3s3p^(3)P_(0)的“幻零”波长进行了理论计算.3s^(2)^(1)S_(0)态的“幻零”波长为266.994(1)nm,3s3p^(3)P_(0)态的“幻零”波长为184.56(7)nm,174.4(1)nm,121.5(1)nm和119.7(2)nm.精确测量这些“幻零”波长,有助于高精度确定光钟态相关跃迁的振子强度或者约化矩阵元,进而降低Al^(+)光钟黑体辐射频移评估的不确定度.同时,对这些“幻零”波长的精密测量,对研究Al~+原子结构具有重要意义. 展开更多
关键词 Al^(+) 极化率 “幻零”波长 CI+MBPT
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激电测深在吉家洼金矿区找矿预测中的应用
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作者 高锋辉 王树新 +2 位作者 梁新辉 庆岩波 高继栓 《黄金》 CAS 2024年第3期78-84,共7页
吉家洼金矿床位于豫西熊耳山金银多金属矿集区内,近年来其深部找矿取得了一定进展。为开展进一步找矿勘查工作,在吉家洼金矿区应用激电测深取得了较好的探测效果。视极化率对含矿地质体的反应较为敏感,激电测深在16勘探线以北探测到高... 吉家洼金矿床位于豫西熊耳山金银多金属矿集区内,近年来其深部找矿取得了一定进展。为开展进一步找矿勘查工作,在吉家洼金矿区应用激电测深取得了较好的探测效果。视极化率对含矿地质体的反应较为敏感,激电测深在16勘探线以北探测到高极化地质体,推测深部存在自北东向南西方向延伸的隐伏含矿斑岩体。通过钻孔原生晕样品测试,发现16勘探线具有高温元素W异常,侧面验证了激电测深的预测结果。该研究结果对熊耳山金银多金属矿集区勘查脉状金银多金属矿化具有一定借鉴意义。 展开更多
关键词 激电测深 吉家洼 金矿床 物探 找矿预测 视极化率
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激电测深法在勘探采空区中的应用和分析
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作者 徐刚 《世界有色金属》 2024年第2期100-102,共3页
激电测深法是一种快速有效、经济无损探查地下采空区的一种地球物理勘探方法,主要通过人工地下直流电场激发,以电测深装置形式,接收、研究地下横、纵向激发极化效应变化的来划分地层和圈定地下采空区位置范围。本文根据工程实例对该方... 激电测深法是一种快速有效、经济无损探查地下采空区的一种地球物理勘探方法,主要通过人工地下直流电场激发,以电测深装置形式,接收、研究地下横、纵向激发极化效应变化的来划分地层和圈定地下采空区位置范围。本文根据工程实例对该方法的技术原理及后期的数据处理推断解释进行研究,分析激电测深在马鞍山市和睦山充填站区探查地下采空区范围的应用,为地下采空区处理和周边边坡的稳定性分析提供科学的依据。 展开更多
关键词 激电测深法 视电阻率 视极化率 采空区
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时间域激发极化法在某多金属矿普查中的应用
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作者 爨伊博 齐坤 +1 位作者 石宗源 梅昌旺 《山西冶金》 CAS 2024年第4期208-210,共3页
激发极化法是通过利用矿石与围岩固有电场在外部电场作用下发生的不同激发极化效应来研究岩矿石基础物性参数的一种找矿手法。在金属矿化探异常区进行中间梯度扫面和对称四极测深电法测量工作,分析了时间域激发极化法在该金属矿的视电... 激发极化法是通过利用矿石与围岩固有电场在外部电场作用下发生的不同激发极化效应来研究岩矿石基础物性参数的一种找矿手法。在金属矿化探异常区进行中间梯度扫面和对称四极测深电法测量工作,分析了时间域激发极化法在该金属矿的视电阻率和极化率特征,查明了矿石异常体的埋深、倾向和产状发育。结果表明,电法解译异常成果与地质与化探资料相吻合,为寻找该区隐伏矿床提供了依据,取得了较好的找矿效果。 展开更多
关键词 激发极化法 对称四极 中间梯度 视极化率 视电阻率
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西藏德新铅多金属矿床地球物理与地球化学综合找矿研究
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作者 李炎 王建国 +3 位作者 魏生云 李国璋 胡建 王志男 《黄金科学技术》 CSCD 北大核心 2024年第3期400-415,共16页
德新铅多金属矿床是冈底斯多金属成矿带西段受构造—岩浆控制的中—低温热液型多金属矿床之一。通过对岩(矿)石电阻率、极化率及主微量元素等物性参数和地球化学特征进行分析,综合解释矿区矿致异常,并利用多元统计分析方法对成矿元素进... 德新铅多金属矿床是冈底斯多金属成矿带西段受构造—岩浆控制的中—低温热液型多金属矿床之一。通过对岩(矿)石电阻率、极化率及主微量元素等物性参数和地球化学特征进行分析,综合解释矿区矿致异常,并利用多元统计分析方法对成矿元素进行研究。结果表明:德新铅多金属矿床矿体的极化率及电阻率与围岩存在明显差异,可划分为低阻高极化和高阻高极化2种类型,对应8处激电异常,推测JD3-5和JD4低阻高极化异常为矿致异常,具有深部找矿潜力,是区内找矿勘查的重点区域之一;Pb、Zn、Cu、Mo、Ni和In等元素相关性显著,是德新铅多金属矿床的主要成矿元素;成矿过程前期主要受中—高温岩浆热液矿化类型Zn-Mo-Pb和Cu-Ni-In的影响,后期主要受含有Sc-Cr-Li和Hf-Be元素的流体及围岩的影响,其中Pb元素受Ni、Mo和In影响强烈,Zn元素受Mo的影响强烈。上述认识能够为找矿预测提供有用的宏观及微观信息,对该区域综合找矿具有重要的指导意义。 展开更多
关键词 电阻率 极化率 激电中梯测量 因子分析 多元线性回归分析法 德新铅多金属矿床 西藏
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Static electric dipole polarizability of lithium atoms in Debye plasmas 被引量:3
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作者 宁丽娜 祁月盈 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第12期180-186,共7页
The static electric dipole polarizabilities of the ground state and n ≤ 3 excited states of a lithium atom embedded in a weekly coupled plasma environment are investigated as a function of the plasma screening radium... The static electric dipole polarizabilities of the ground state and n ≤ 3 excited states of a lithium atom embedded in a weekly coupled plasma environment are investigated as a function of the plasma screening radium. The plasma screening of the Coulomb interaction is described by the Debye-Hiickel potential and the interaction between the valence electron and the atomic core is described by a model potential. The electron energies and wave functions for both the bound and continuum states are calculated by solving the SchrSdinger equation numerically using the symplectic integrator. The oscillator strengths, partial-wave, and total static dipole polarizabilities of the ground state and n ≤ 3 excited states of the lithium atom are calculated. Comparison of present results with those of other authors, when available, is made. The results for the 2s ground state demonstrated that the oscillator strengths and the static dipole polarizabilities from np orbitals do not always increase or decrease with the plasma screening effect increasing, unlike that for hydrogen-like ions, especially for 2s→3p transition there is a zero value for both the oscillator strength and the static dipole polarizability for screening length D = 10.3106a0, which is associated with the Cooper minima. 展开更多
关键词 static electric dipole polarizability Debye plasmas lithium atom
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Critical radius and dipole polarizability for a confined system 被引量:1
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作者 许田 曹庄琪 +2 位作者 欧永成 沈启舜 视国龙 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第6期1172-1176,共5页
The analytical transfer matrix method (ATMM) is applied to calculating the critical radius τc and the dipole polarizability αd in two confined systems: the hydrogen atom and the Hulthēén potential. We find ... The analytical transfer matrix method (ATMM) is applied to calculating the critical radius τc and the dipole polarizability αd in two confined systems: the hydrogen atom and the Hulthēén potential. We find that there exists a linear relation between τe^1/2 and the quantum number nτ for a fixed angular quantum number l, moreover, the three bounds of αd(αd^K,αd^B,αd^U) satisfy an inequality:αd^K≤αd^B≤αd^U,A comparison betwen the ATMM,the exact numerical analysis, and the variational wavefunctions shows that our method works very well in the systems. 展开更多
关键词 ATMM confined system critical radius dipole polarizability
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Optical Basicity and Polarizability of Nd<sup>3+</sup>-Doped Bismuth Borate Glasses 被引量:3
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作者 Beena Bhatia S. L. Meena +1 位作者 Vishal Parihar Monika Poonia 《New Journal of Glass and Ceramics》 2015年第3期44-52,共9页
This paper reports on different physical and optical properties of Nd3+-doped bismuth borate glasses. The glasses containing Nd3+ in (25 - x)Bi2O3:20Li2O:20ZnO:35B2O3:xNd2O3 (where x = 1, 1.5, 2 mol%) have been prepar... This paper reports on different physical and optical properties of Nd3+-doped bismuth borate glasses. The glasses containing Nd3+ in (25 - x)Bi2O3:20Li2O:20ZnO:35B2O3:xNd2O3 (where x = 1, 1.5, 2 mol%) have been prepared by melt-quenching method. The amorphous nature of the glasses was confirmed by X-ray diffraction studies. The physical parameters like dielectric constant, refractive index, ionic concentration, oxygen-packing density, inter ionic distance, polaronradius, reflection loss, energy gap, molar refractivity, molar polarizability, electronic polarizability, optical basicity and field strength are computed. On the basis of the measured values of the density and refractive index, the Nd3+ ion concentration in glasses, the polarizability of oxide ions and optical basicity were theoretically determined. The theoretical value of average electronic polarizability and oxide ion polarizability were calculated by using Lorentz-Lorenz formula. Theoretical optical basicity of the glasses is evaluated based on equation proposed by Duffy and Ingram. The metallization criterion has also been calculated on the basis of refractive index and energy gap. The large value of metallization criterion indicates that the glass materials are insulators. The results obtained predict the nature of bonding in the present glasses and provide basis for developing new nonlinear optical material. 展开更多
关键词 NEODYMIUM Based Glass Optical BASICITY polarizability METALLIZATION Criterion
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Refractive Index and Electronic Polarizability of Ternary Chalcopyrite Semiconductors 被引量:1
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作者 KUMAR V. SINHA Anita +2 位作者 SINGH B.P. SINHA A.P. JHA V. 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第12期147-151,共5页
Simple models are proposed for the calculation of refractive index n and electronic polarizability α of AⅠBⅢC2Ⅵ and AⅡBⅣC2Ⅴ compounds of groups of chalcopyrite semiconductors from their energy gap data. The val... Simple models are proposed for the calculation of refractive index n and electronic polarizability α of AⅠBⅢC2Ⅵ and AⅡBⅣC2Ⅴ compounds of groups of chalcopyrite semiconductors from their energy gap data. The values family and 12 compounds of AⅡBⅣC2Ⅴ family are calculated for the work. The proposed models are applicable for the whole range of energy gap materials. The calculated values are compared with the available experimental and reported values. A fairly good agreement between them is obtained. 展开更多
关键词 TE In Refractive Index and Electronic polarizability of Ternary Chalcopyrite Semiconductors
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Temperature Dependence of Polarizability and Dispersion in Three,Two and One Dimensional Electron Gases
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作者 燕保荣 孔令华 +1 位作者 吕建红 胡希伟 《Plasma Science and Technology》 SCIE EI CAS CSCD 2009年第5期515-520,共6页
Both temperature dependence of polarizability and plasmon dispersion in unmagnetized metal (or semiconductor) electron gases are investigated in this paper. It is obtained that, with a continuous variation of temper... Both temperature dependence of polarizability and plasmon dispersion in unmagnetized metal (or semiconductor) electron gases are investigated in this paper. It is obtained that, with a continuous variation of temperature in a large region, the polarizability and dispersion change non-monotonously. The static polarizability X(q, w =0, μ, T) and dispersion wp(q, T) for finite T in three, two and one dimensional electron gases are calculated numerically. In addition, dispersion relation w(q) at a definite temperature (T ≠0) is similar to that at T = 0. 展开更多
关键词 polarizability plasmon dispersion two dimensional electron gas TEMPERATUREDEPENDENCE
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Effects of Electron Donor and Different Solvents on Polarizability and Second Hyperpolarizability of Diradical Complex Involving X(X=B,Al,Ga)
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作者 LIU Hai-bo QIU Yong-qing +2 位作者 YANG Guo-chun LIU Chun-guang SUN Shi-ling 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第2期308-312,共5页
The polarizability(α) and second hyperpolarizability(γ) were systemically investigated for singlet diradical complex involving X(X=B,Al,Ga) atom.The results show that both the α and γ can be effectively tune... The polarizability(α) and second hyperpolarizability(γ) were systemically investigated for singlet diradical complex involving X(X=B,Al,Ga) atom.The results show that both the α and γ can be effectively tuned by varying the distance R(between compound A and a water molecule) and acceptor atom X.The lone pair of electrons from the O atom of the water molecule entered into the vacant p orbital of atom X,which increased the diradical character and led to the increase of the α and γ values.Furthermore,the polarizable continuum model(PCM) was used to test the effects of H2O and CCl4 solvents on the α and γ values.Both the α and γ values of the studied diradical complex 1a(1b,1c) in H2O and CCl4 were uniformly enhanced.And the solvent effects of H2O on either α or γ were larger than those of CCl4. 展开更多
关键词 polarizability Second hyperpolarizability Diradical character Polarizable continuum model(PCM)
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Influence of Polarizability and Covalency on ^(151)Eu Mossbauer Isomer Shifts
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《Journal of Rare Earths》 SCIE EI CAS CSCD 2000年第4期288-288,共1页
关键词 EU Influence of polarizability and Covalency on Mossbauer Isomer Shifts
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Calculations of atomic polarizability for beryllium using MCDHF method
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作者 董辉 蒋军 +2 位作者 武中文 董晨钟 Gediminas Gaigalas 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第4期211-215,共5页
Based on the fully relativistic multiconfiguration Dirac-Hartree-Fock(MCDHF)method and the corresponding program package GRASP2018,a new program for calculating the polarizabilities is developed.As the first applicati... Based on the fully relativistic multiconfiguration Dirac-Hartree-Fock(MCDHF)method and the corresponding program package GRASP2018,a new program for calculating the polarizabilities is developed.As the first application,the static electric-dipole polarizabilities of the ground state 2s^(2)^(1)S_(0) and excited state 2s2p^(3)P_(0) of beryllium are calculated.By means of these polarizabilities,the blackbody radiation(BBR)shift of the 2s2p^(3)P_(0)→2s^(2)^(1)S_(0)clock transition is determined.The present results agree very well with other available theoretical results. 展开更多
关键词 POLARIZABILITIES MCDHF blackbody radiation shift
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Nonlinear Polarizability of Erythrocytes in Non-Uniform Alternating Electric Field
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作者 Konstantin V. Generalov Vladimir M. Generalov +5 位作者 Alexander S. Safatov Alexander G. Durymanov Galins A. Buryak Margarita V. Kruchinina Mikhail I. Voevoda Andrey A. Gromov 《Open Journal of Biophysics》 2014年第3期97-103,共7页
Nonlinear polarizability of erythrocytes in non-uniform alternating electric field (NUAEF) was proved theoretically and experimentally by dielectrophoresis method. The paper presents experimental evidence of the nonli... Nonlinear polarizability of erythrocytes in non-uniform alternating electric field (NUAEF) was proved theoretically and experimentally by dielectrophoresis method. The paper presents experimental evidence of the nonlinear polarizability of erythrocytes in the non-uniform alternating electric field. The rotation of erythrocyte around its own axis at more than one revolution per second in the non-uniform alternating electric field in the frequency range and the electric field intensity?is the evidence of its nonlinear polarizability. The theoretical analysis of the density of electric charges capable of overcoming the membrane potential was carried out on the basis of statistical mechanics, the thermal equilibrium in which the particle stays. The nonlinear polarizability of the erythrocyte emerges if the voltage on the membrane exceeds?, which was theoretically proved. The alternating electric field from the donor erythrocyte with the amplitude exceeding forms the constant component of the current? in the cytoplasm of the recipient erythrocyte whose energy can be considered as a signal one. The nonlinear equivalent electric circuit of the cell was proposed. 展开更多
关键词 Dielectrophoresis polarizability ROTATION ERYTHROCYTE NONLINEARITY
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Activity Trends in Desoxy Anthrapyrazoles: The Influence of Molar Volume, Polarizability and Lipophilicity of N<sub>2</sub>C<sub>5</sub>Side Chains on Their Anticancer Response
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作者 Howida A. Hashim Mohamed Osman M. A. El-Fakii Ahmed Elsadig M. Saeed 《Computational Chemistry》 2020年第2期17-26,共10页
QSAR methodology was used to assess the effects of lipophilicity (logP), molar volume (MV) and polarizability (pl) of the side chains at N2 and C5 of 20 known desoxy anthrapyrazoles on their in vitro anticancer activi... QSAR methodology was used to assess the effects of lipophilicity (logP), molar volume (MV) and polarizability (pl) of the side chains at N2 and C5 of 20 known desoxy anthrapyrazoles on their in vitro anticancer activity expressed as the negative logarithm of the inhibitory concentration of 50% of L1210 murine leukemia cell line (1/logIC50). The main data set shows poor correlations between biological response and the descriptors with exception of MV of the C5 side chain, where a moderate correlation was discerned ( =0.60, n = 18, two outliers). To extract more information regarding mechanism, the main data set was visually classified to three clusters depending on N2 side chain. Cluster 1 containing six 5-substituted 2-[(2-hydroxyethyl) amino] ethyl anthrapyrazoles;cluster 2 contains ten 5-subsitutes 2-(diethyl amino) ethyl anthrapyrazoles and cluster 3 contains four anthrapyrazoles with miscellaneous substituents at both N2 and C5. For cluster 1, MV and pl of C5 show high correlation with biological response (R2’s = 0.75 and 0.72 respectively) while logP gives a weak correlation (R2 = 0.44). For cluster 2, the correlations of logP and pl of C2side chain are higher (=0.66 and 0.62 respectively) compared with MV (=0.16). Cluster 3 shows very poor correlation with all descriptors (~0.3). This indicates mechanistic distinction between the three clusters. Derived descriptors which represent the difference between the descriptors of N2 and C5 side chains where used to explore the presence of interplay between these descriptors in affecting variability of the biological response. 展开更多
关键词 polarizability MOLAR Volume LIPOPHILICITY Anthrapyrazoles Murine
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