期刊文献+
共找到14篇文章
< 1 >
每页显示 20 50 100
局域Bjerhammar问题解算理论和断层位错引起的单层密度变化 被引量:1
1
作者 申重阳 朱思林 +1 位作者 甘家思 白志明 《地壳形变与地震》 CSCD 2000年第3期17-26,共10页
为了利用大地测量数据解算地壳内部密度时变 ,并为研究地震孕育过程和地震前兆中物质密度时变信息提供理论依据 ,研究了局域 Bjerhammar球面单层密度时变问题的平面解算理论 ;给出了不同投影下 Bjerhammar球面单层密度时变及相关重力位... 为了利用大地测量数据解算地壳内部密度时变 ,并为研究地震孕育过程和地震前兆中物质密度时变信息提供理论依据 ,研究了局域 Bjerhammar球面单层密度时变问题的平面解算理论 ;给出了不同投影下 Bjerhammar球面单层密度时变及相关重力位场的严格解式 ;导出了局域 Bjerhammar问题解算理论的使用条件 ,即满足一定精度要求的门限 R和ψ0 的严格解析关系式 ;给出了不同 Bjerhammar平面上的 q*t 之间的关系式 ,并根据一般迭代解算 q*t 的收敛特性 ,提出了空间域的分步迭代算法和空间域、波数域 (二步 )混合算法 ,从理论上解决了解算局域单层密度时变的稳定问题 (当 R较小或 H较大时 )。然后以此为基础 ,研究了位错引起的单层密度变化 ,并给出了不同点位错、断层位错类型引起的单层密度变化的解析表达式和断层位错在不同深度或不同 Bjerhammar球上引起的单层密度变化图像。 展开更多
关键词 局域问题 单层密度 理论 断层运动 地震
下载PDF
检验施工放样点与设计值偏差的方法
2
作者 蒋进优 《山西建筑》 2015年第13期202-204,共3页
对检验施工放样点与设计值偏差的测定方法进行了具体的介绍,把极值概念引入距离测量,给出了极值法、面积法、夹角法、坐标转化法公式,详细阐述了全站仪直接测定法和Auto CAD法的具体操作步骤,以提高测量的准确性。
关键词 检验 放样点 实测 理论解算
下载PDF
Infrared Photodisssociation Spectroscopy of Boron Carbonyl Cation Complexes
3
作者 金佳晔 王冠军 周鸣飞 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第1期47-52,I0001,共7页
The boron carbonyl cation complexes B(CO)3+, B(CO)4+ and B2(CO)4+ are studied by infrared photodissociation spectroscopy and theoretical calculations. The B(CO)4+ ions are characterized to be very weakly b... The boron carbonyl cation complexes B(CO)3+, B(CO)4+ and B2(CO)4+ are studied by infrared photodissociation spectroscopy and theoretical calculations. The B(CO)4+ ions are characterized to be very weakly bound complexes involving a B(CO)3+ core ion, which is predicted to have a planar D3h structure with the central boron retaining the most favorable 8-electron configuration. The B2(C0)4+ cation is determined to have a planar D2h structure involving a B-B one and half bond. The analysis of the B-CO interactions with the EDA- NOCV method indicates that the OC→B cr donation is stronger than the B-+CO π back donation in both ions. 展开更多
关键词 Boron carbonyl Donor-acceptor bonding Infrared photodissociation spec- troscopy Theoretical calculations
下载PDF
ANALYSIS OF WAVEGUIDE PROBLEMS USING A RELAXED ITERATIVE DOMAIN DECOMPOSITION METHOD COMBINED WITH MULTIFRONTAL ALGORITHM 被引量:2
4
作者 Zhu Hanqing Wu Zhengde (Applied Physics Institute, University of Electronic Science and Technology of China, Chengdu 610054)K. M. Luk(Department of Electronic Eng., City University of Hong Kong, Kowloon, Hong Kong SAR, China) 《Journal of Electronics(China)》 2003年第2期110-115,共6页
In this paper, an absorbing Fictitious Boundary Condition (FBC) is presented to generate an iterative Domain Decomposition Method (DDM) for analyzing waveguide problems.The relaxed algorithm is introduced to improve t... In this paper, an absorbing Fictitious Boundary Condition (FBC) is presented to generate an iterative Domain Decomposition Method (DDM) for analyzing waveguide problems.The relaxed algorithm is introduced to improve the iterative convergence. And the matrix equations are solved using the multifrontal algorithm. The resulting CPU time is greatly reduced.Finally, a number of numerical examples are given to illustrate its accuracy and efficiency. 展开更多
关键词 Fictitious boundary condition Domain decomposition method Relaxed algorithm Multifrontal algorithm Waveguide problem
下载PDF
New Exact Travelling Wave Solutions to Kundu Equation 被引量:1
5
作者 HUANG Ding-Jiang LI De-Sheng, ZHANG Hong-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第6X期969-976,共8页
Based on a first-order nonlinear ordinary differential equation with six-degree nonlinear term, we first present a new auxiliary equation expansion method and its algorithm. Being concise and straightforward, the meth... Based on a first-order nonlinear ordinary differential equation with six-degree nonlinear term, we first present a new auxiliary equation expansion method and its algorithm. Being concise and straightforward, the method is applied to the Kundu equation. As a result, some new exact travelling wave solutions are obtained, which include bright and dark solitary wave solutions, triangular periodic wave solutions, and singular solutions. This algorithm can also be applied to other nonlinear evolution equations in mathematical physics. 展开更多
关键词 nonlinear evolution equation Kundu equation ordinary differential equation ALGORITHM exact solution travelling wave solution
下载PDF
Interzeolite transformation from FAU to CHA and MFI zeolites monitored by UV Raman spectroscopy 被引量:3
6
作者 Juan Zhang Yueying Chu +4 位作者 Xiaolong Liu Hao Xu Xiangju Meng Zhaochi Feng Feng-Shou Xiao 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第12期1854-1859,共6页
As a powerful and sensitive tool for the characterization of zeolite building units,UV Raman spectroscopy has been used to monitor interzeolite transformation from FAU to CHA and MFI zeolites.The results show that the... As a powerful and sensitive tool for the characterization of zeolite building units,UV Raman spectroscopy has been used to monitor interzeolite transformation from FAU to CHA and MFI zeolites.The results show that the behavior of double 6-membered rings(D6Rs)in the FAU zeolite framework plays an important role during the formation of the target product in the interzeolite transformation.For the transformation of FAU to CHA,because both zeolites contain the same D6R units,direct transformation occurs,in which the D6Rs were largely unchanged.In contrast,for the transformation of FAU to MFI,the D6Rs can be divided into two single 6-membered rings(S6Rs),which further assembled into the MFI structure.In this crystallization,5-membered rings(5Rs)are only observed in the MFI framework formation,suggesting that the basic building units in the transformation of FAU to MFI are S6Rs rather than 5Rs.These insights will be helpful for further understanding of the interzeolite transformation. 展开更多
关键词 Interzeolite transformation UV Raman spectroscopy DFT calculation Double 6-memberred rings Decomposition and re-assembly
下载PDF
KSSOLV-GPU:an Efficient GPU-Enabled MATLAB Toolbox for Solving the Kohn-Sham Equations within Density Functional Theory in Plane-Wave Basis Set
7
作者 Zhen-lin Zhang Shi-zhe Jiao +5 位作者 Jie-lan Li Wen-tiao Wu Ling-yun Wan Xin-ming Qin Wei Hu Jin-long Yang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2021年第5期552-564,I0002,共14页
KSSOLV(Kohn-Sham Solver)is a MATLAB(Matrix Laboratory)toolbox for solving the Kohn-Sham density functional theory(KS-DFT)with the plane-wave basis set.In the KS-DFT calculations,the most expensive part is commonly the... KSSOLV(Kohn-Sham Solver)is a MATLAB(Matrix Laboratory)toolbox for solving the Kohn-Sham density functional theory(KS-DFT)with the plane-wave basis set.In the KS-DFT calculations,the most expensive part is commonly the diagonalization of Kohn-Sham Hamiltonian in the self-consistent field(SCF)scheme.To enable a personal computer to perform medium-sized KS-DFT calculations that contain hundreds of atoms,we present a hybrid CPU-GPU implementation to accelerate the iterative diagonalization algorithms implemented in KSSOLV by using the MATLAB built-in Parallel Computing Toolbox.We compare the performance of KSSOLV-GPU on three types of GPU,including RTX3090,V100,and A100,with conventional CPU implementation of KSSOLV respectively and numerical results demonstrate that hybrid CPU-GPU implementation can achieve a speedup of about 10 times compared with sequential CPU calculations for bulk silicon systems containing up to 128 atoms. 展开更多
关键词 Kohn-Sham Solver Density functional theory Iterative eigensolver MATLAB GPU
下载PDF
Determination of metastable zone and induction time of analgin for cooling crystallization 被引量:7
8
作者 Ling Zhou Zhao Wang +3 位作者 Meijing Zhang Mingxia Guo Shijie Xu Qiuxiang Yin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第3期313-318,共6页
The solubility, metastable zone width, and induction time of analgin for unseeded batch cooling crystallization in ethanol–aqueous system were experimentally determined. The solubility data could be well described by... The solubility, metastable zone width, and induction time of analgin for unseeded batch cooling crystallization in ethanol–aqueous system were experimentally determined. The solubility data could be well described by the van't Hoff equation model. The metastable zone width at various cooling rates was measured, and some parameters of nucleation kinetic were calculated using the Ny'vlt theory. Furthermore, the induction period of various temperatures and supersaturation ratios was also measured. According to classical nucleation theory, some nucleation parameters and interfacial energy was calculated through the induction time(t_(ind)) data. Homogeneous nucleation tended to occur when the supersaturation is high, whereas heterogeneous nucleation was more likely to occur when the supersaturation is low. 展开更多
关键词 ANALGIN Cooling crystallization Primary nucleation Metastable zone Induction time
下载PDF
Demonstration of Inverse Scattering Transform in G-L-M Formalism for NLS Equation in Normal Dispersion with Non-vanishing Boundary
9
作者 YANG Chun-Nuan HE Jin-Chun HUANG Nian-Ning 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第12期1375-1380,共6页
Using the integral representation of the Jost solution,we deduce some conditions as the kernel functionN(x,y,t)if the Jost solution satisfies the two Lax equations.Then we verify the multi-soliton solution of NLS equa... Using the integral representation of the Jost solution,we deduce some conditions as the kernel functionN(x,y,t)if the Jost solution satisfies the two Lax equations.Then we verify the multi-soliton solution of NLS equationwith non-vanishing boundary conditions if we prove that these conditions can be demonstrated by the GLM equation,which determines the kernel function N(x,y,t)in according to the inverse scattering method. 展开更多
关键词 NLS^+ equation inverse scattering method Gel'fand Levitan Marchenko equation
下载PDF
Thermochemical properties and thermokinetic behavior of energetic triazole ionic salts 被引量:4
10
作者 ZHAO FengQi XUE Liang +6 位作者 XING XiaoLing HU RongZu ZHOU ZhiMing GAO HongXu YI JianHua XU SiYu PEI Qing 《Science China Chemistry》 SCIE EI CAS 2011年第3期461-474,共14页
The properties of dissolution in different solvents,the specific heat capacity and thermal decomposition process under the non-isothermal conditions for energetic triazole ionic salts 1,2,4-triazolium nitrate(1a),1,2,... The properties of dissolution in different solvents,the specific heat capacity and thermal decomposition process under the non-isothermal conditions for energetic triazole ionic salts 1,2,4-triazolium nitrate(1a),1,2,3-triazolium nitrate(1b),3,4,5triamino-1,2,4-triazolium nitrate(2a),3,4,5-triamino-1,2,4-triazolium dinitramide(2b)were precisely measured using a Calvet Microcalorimeter.The thermochemical equation,differential enthalpies of dissolution(△difH m ),standard molar enthalpies of dissolution(△difH m ),apparent activation energy(E),pre-exponential constant(A),kinetic equation,linear relationship of specific heat capacity with temperature over the temperature range from 283 to 353 K,standard molar heat capacity(C p,m)and enthalpy,entropy and Gibbs free energy at 283–353 K,taking 298.15 K as the benchmark for 1a,1b,2a and 2b were obtained with treating experimental data and theoretical calculation method.The kinetic and thermodynamic parameters of thermal decomposition reaction,critical temperature of thermal explosion(Tb),self-accelerating decomposition temperature(TSADT)and adiabatic time-to-explosion(t)of 1a,1b,2a and 2b were calculated.Their heat-resistance abilities were evaluated.Information was obtained on the relation between molecular structures and properties of 1a,1b,2a and 2b. 展开更多
关键词 energetic triazole ionic salts thermochemical properties thermokinetic behavior thermal safety
原文传递
Conversion of bimetallic MOF to Ru-doped Cu electrocatalysts for efficient hydrogen evolution in alkaline media 被引量:8
11
作者 Mengya Yang Long Jiao +7 位作者 Huilong Dong Liujiang Zhou Changqing Teng Dongming Yan Tian-Nan Ye Xiaoxin Chen Yi Liu Hai-Long Jiang 《Science Bulletin》 SCIE EI CSCD 2021年第3期257-264,M0004,共9页
The rational design and construction of inexpensive and highly active electrocatalysts for hydrogen evolution reaction(HER)is of great importance for water splitting.Herein,we develop a facile approach for preparation... The rational design and construction of inexpensive and highly active electrocatalysts for hydrogen evolution reaction(HER)is of great importance for water splitting.Herein,we develop a facile approach for preparation of porous carbon-confined Ru-doped Cu nanoparticles(denoted as Ru-Cu@C)by direct pyrolysis of the Ru-exchanged Cu-BTC metal–organic framework.When served as the electrocatalyst for HER,strikingly,the obtained Ru-Cu@C catalyst exhibits an ultralow overpotential(only 20 mV at 10 mA cm^(-2))with a small Tafel slope of 37 m V dec^(-1)in alkaline electrolyte.The excellent performance is comparable or even superior to that of commercial Pt/C catalyst.Density functional theory(DFT)calculations confirm that introducing Ru atoms into Cu nanocrystals can significantly alter the desorption of H_(2) to achieve a close-to-zero hydrogen adsorption energy and thereby boost the HER process.This strategy gives a fresh impetus to explore low-cost and high-performance catalysts for HER in alkaline media. 展开更多
关键词 Metal–organic framework Ru-doped Cu nanoparticles Hydrogen evolution reaction Alkaline media Hydrogen adsorption energy
原文传递
ON THE NUMBER OF FIXED POINTS OF NONLINEAR OPERATORS AND APPLICATIONS 被引量:3
12
作者 SUNJingxian ZHANGKemei 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2003年第2期229-235,共7页
In this paper, the famous Amann three-solution theorem is generalized. Multiplicity question of fixed points for nonlinear operators via two coupled parallel sub-super solutions is studied. Under suitable conditions, ... In this paper, the famous Amann three-solution theorem is generalized. Multiplicity question of fixed points for nonlinear operators via two coupled parallel sub-super solutions is studied. Under suitable conditions, the existence of at least six distinct fixed points of nonlinear operators is proved. The theoretical results are then applied to nonlinear system of Hammerstein integral equations. 展开更多
关键词 CONE fixed point index theory uniformly positive operator parallelsub-super solutions
原文传递
Progress in noncommutative function theory
13
作者 MUHLY Paul S SOLEL Baruch 《Science China Mathematics》 SCIE 2011年第11期2275-2294,共20页
In this expository paper,we describe the study of certain non-self-adjoint operator algebras,the Hardy algebras,and their representation theory.We view these algebras as algebras of (operator valued) functions on thei... In this expository paper,we describe the study of certain non-self-adjoint operator algebras,the Hardy algebras,and their representation theory.We view these algebras as algebras of (operator valued) functions on their spaces of representations.We will show that these spaces of representations can be parameterized as unit balls of certain W*-correspondences and the functions can be viewed as Schur class operator functions on these balls.We will provide evidence to show that the elements in these (non commutative) Hardy algebras behave very much like bounded analytic functions and the study of these algebras should be viewed as noncommutative function theory. 展开更多
关键词 Hardy algebras tensor algebras Schur class REPRESENTATIONS W^*-correspondence
原文传递
Unified calculation of eigen-solutions in power systems based on matrix perturbation theory
14
作者 LI Yan GAO WenZhong +2 位作者 JIANG JiuChun WANG ChenShan MULJADI Eduard 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第8期1594-1601,共8页
Calculation of eigen-solutions plays an important role in the small signal stability analysis of power systems.In this paper,a novel approach based on matrix perturbation theory is proposed for the calculation of eige... Calculation of eigen-solutions plays an important role in the small signal stability analysis of power systems.In this paper,a novel approach based on matrix perturbation theory is proposed for the calculation of eigen-solutions in a perturbed system.Rigorous theoretical analysis is conducted on the solution of distinct,multiple,and close eigen-solutions,respectively,under perturbations of parameters.The computational flowchart of the unified solution of eigen-solutions is then proposed,aimed toward obtaining eigen-solutions of a perturbed system directly with algebraic formulas without solving an eigenvalue problem repeatedly.Finally,the effectiveness of the matrix perturbation based approach for eigen-solutions’calculation in power systems is verified by numerical examples on a two-area four-machine system. 展开更多
关键词 matrix perturbation matrix spectrum decomposition shift method unified solution approach eigen-solutions
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部