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界嵴连接蛋白43分布的增龄性变化与电传导异向性的关系 被引量:4
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作者 金立军 黄从新 +5 位作者 杨沙宁 李军川 陈廷煊 吴钢 谢强 王腾 《中国心脏起搏与心电生理杂志》 2004年第2期120-123,共4页
为探讨界嵴组织连接蛋白 4 3(Cx4 3)的增龄性变化及其与电传导异向性的关系 ,采用新西兰幼年白兔 (2 0~ 30天 )、成年兔 (6~ 8月 )、老年兔 (2 6~ 2 8月 )界嵴组织行Masson染色和免疫组化检测Cx4 3。与各年龄组月龄相配对的家兔各 7... 为探讨界嵴组织连接蛋白 4 3(Cx4 3)的增龄性变化及其与电传导异向性的关系 ,采用新西兰幼年白兔 (2 0~ 30天 )、成年兔 (6~ 8月 )、老年兔 (2 6~ 2 8月 )界嵴组织行Masson染色和免疫组化检测Cx4 3。与各年龄组月龄相配对的家兔各 7只 ,采用玻璃微电极技术测量界嵴纵向 (VL)及横向 (VT)传导速度。结果 :界嵴组织可见P样细胞单个或成群分布。各年龄组Cx4 3阳性表达面积无差别 ,幼年兔Cx4 3表达多在细胞的侧 侧连接上 ;成年兔端 端表达比侧 侧表达为多 ;而老年兔则以端 端连接表达为主。随着年龄增加 ,各年龄组VT 和VL 也发生改变 ,传导异向性(VL/VT)明显加大。端 端 /侧 侧Cx4 3阳性面积比率与VL/VT 明显相关 (r =0 .90 3)。结论 :界嵴Cx4 3表达的增龄性变化与电传导异向性改变有关 ,后者在特定的生理或病理条件下可能是界嵴产生和 /或参与房性心律失常的物质基础。 展开更多
关键词 界嵴连接蛋白43 分布 增龄性变化 传导异向性 界嵴 衰老 生理学
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Analysis of Resistance-related Proteins in Rice Against Brown Planthopper by Two-dimensional Electrophoresis 被引量:12
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作者 陈荣智 翁清妹 +2 位作者 黄臻 祝莉莉 何光存 《Acta Botanica Sinica》 CSCD 2002年第4期427-432,共6页
A recombinant inbred population (RI) was constructed from a cross between B5, an introgression. line from the wild rice Oryza officinalis Wall. ex Watt, and susceptible cultivar Minghui 63 ( O. sativa L.). The brown p... A recombinant inbred population (RI) was constructed from a cross between B5, an introgression. line from the wild rice Oryza officinalis Wall. ex Watt, and susceptible cultivar Minghui 63 ( O. sativa L.). The brown planthopper ( BPH) resistances of RI lines were evaluated. Based on bulked segregant analysis (BSA), two protein bulks were made by extracting proteins from equally mixed seedlings of extremely resistant and susceptible plants selected from the RI population, respectively. Two-dimensional electrophoresis was used to detect the changes of polypeptide pattern. Results showed that a protein P40 ( pI 6.3, Mw 40 kD) was significantly reduced or vanished after BPH infestation for 48 h in the susceptible bulk, while it remained uninfluenced in the resistant bulk. In connection with the physiological changes of the resistant and susceptible lines subjected to BPH sucking, we suppose that the protein P40 is related to the interaction responses of lice plants to BPH infestation. 展开更多
关键词 RICE recombinant inbred lines brown planthopper resistance two-dimensional electrophoresis
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Forward modeling of marine DC resistivity method for a layered anisotropic earth 被引量:2
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作者 殷长春 张平 蔡晶 《Applied Geophysics》 SCIE CSCD 2016年第2期279-287,417,共10页
Since the ocean bottom is a sedimentary environment wherein stratification is well developed, the use of an anisotropic model is best for studying its geology. Beginning with Maxwell's equations for an anisotropic mo... Since the ocean bottom is a sedimentary environment wherein stratification is well developed, the use of an anisotropic model is best for studying its geology. Beginning with Maxwell's equations for an anisotropic model, we introduce scalar potentials based on the divergence-free characteristic of the electric and magnetic (EM) fields. We then continue the EM fields down into the deep earth and upward into the seawater and couple them at the ocean bottom to the transmitting source. By studying both the DC apparent resistivity curves and their polar plots, we can resolve the anisotropy of the ocean bottom. Forward modeling of a high-resistivity thin layer in an anisotropic half-space demonstrates that the marine DC resistivity method in shallow water is very sensitive to the resistive reservoir but is not influenced by airwaves. As such, it is very suitable for oil and gas exploration in shallowwater areas but, to date, most modeling algorithms for studying marine DC resistivity are based on isotropic models. In this paper, we investigate one-dimensional anisotropic forward modeling for marine DC resistivity method, prove the algorithm to have high accuracy, and thus provide a theoretical basis for 2D and 3D forward modeling. 展开更多
关键词 Electrical anisotropy Marine DC resistivity method Forward modeling Field continuation algorithm
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A High Breakdown Voltage Thin SOI Device with a Vertically Linearly Graded Concentration Drift Region 被引量:1
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作者 陆生礼 孙智林 +1 位作者 孙伟锋 时龙兴 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第12期2286-2289,共4页
As the thickness of an SOI layer varies,a minimum breakdown voltage is reached when the thickness is about 2μm. The vertical electric field of the SOI LDMOS with a drift region which is vertically linearly graded is ... As the thickness of an SOI layer varies,a minimum breakdown voltage is reached when the thickness is about 2μm. The vertical electric field of the SOI LDMOS with a drift region which is vertically linearly graded is constant. The vertically linearly graded concentration drift can be achieved by impurity implanting followed by thermal diffusion. In this way,the vertical breakdown voltage of SOI LDMOS with 2μm thickness SOI layer can be improved by 43%. The on-state resistance is lowered by 24 % because of the higher impurity concentration of the SOI surface. 展开更多
关键词 SOI vertically linearly graded concentration breakdown voltage LDMOS
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3D anisotropic modeling and identification for airborne EM systems based on the spectral-element method 被引量:4
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作者 黄鑫 殷长春 +3 位作者 曹晓月 刘云鹤 张博 蔡晶 《Applied Geophysics》 SCIE CSCD 2017年第3期419-430,461,462,共14页
The airborne electromagnetic (AEM) method has a high sampling rate and survey flexibility. However, traditional numerical modeling approaches must use high-resolution physical grids to guarantee modeling accuracy, e... The airborne electromagnetic (AEM) method has a high sampling rate and survey flexibility. However, traditional numerical modeling approaches must use high-resolution physical grids to guarantee modeling accuracy, especially for complex geological structures such as anisotropic earth. This can lead to huge computational costs. To solve this problem, we propose a spectral-element (SE) method for 3D AEM anisotropic modeling, which combines the advantages of spectral and finite-element methods. Thus, the SE method has accuracy as high as that of the spectral method and the ability to model complex geology inherited from the finite-element method. The SE method can improve the modeling accuracy within discrete grids and reduce the dependence of modeling results on the grids. This helps achieve high-accuracy anisotropic AEM modeling. We first introduced a rotating tensor of anisotropic conductivity to Maxwell's equations and described the electrical field via SE basis functions based on GLL interpolation polynomials. We used the Galerkin weighted residual method to establish the linear equation system for the SE method, and we took a vertical magnetic dipole as the transmission source for our AEM modeling. We then applied fourth-order SE calculations with coarse physical grids to check the accuracy of our modeling results against a 1D semi-analytical solution for an anisotropic half-space model and verified the high accuracy of the SE. Moreover, we conducted AEM modeling for different anisotropic 3D abnormal bodies using two physical grid scales and three orders of SE to obtain the convergence conditions for different anisotropic abnormal bodies. Finally, we studied the identification of anisotropy for single anisotropic abnormal bodies, anisotropic surrounding rock, and single anisotropic abnormal body embedded in an anisotropic surrounding rock. This approach will play a key role in the inversion and interpretation of AEM data collected in regions with anisotropic geology. 展开更多
关键词 Spectral-element method ANISOTROPY frequency-domain AEM GLL interpolation basis function forward m odeling
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Fabrication of Silicon Crystal-Facet-Dependent Nanostructures by Electron-Beam Lithography
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作者 杨香 韩伟华 +2 位作者 王颖 张杨 杨富华 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第6期1057-1061,共5页
Silicon crystal-facet-dependent nanostructures have been successfully fabricated on a (100)-oriented silicon-oninsulator wafer using electron-beam lithography and the silicon anisotropic wet etching technique. This ... Silicon crystal-facet-dependent nanostructures have been successfully fabricated on a (100)-oriented silicon-oninsulator wafer using electron-beam lithography and the silicon anisotropic wet etching technique. This technique takes advantage of the large difference in etching properties for different crystallographic planes in alkaline solution. The minimum size of the trapezoidal top for those Si nanostructures can be reduced to less than 10nm. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) observations indicate that the etched nanostructures have controllable shapes and smooth surfaces. 展开更多
关键词 silicon nanostructure anisotropic wet etching electron-beam lithography
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Inverse Halogen Bonds Interactions Involving Br Atom in the Electronic Deficiency Systems of CH3+… Br-Y (Y--H, CCH, CN, NC)
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作者 刘艳芝 袁煜 +4 位作者 吕玲玲 朱元成 唐慧安 左国防 李志锋 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第3期284-294,I0003,共12页
Inverse halogen bonds interactions involving Br in the electronic deficiency systems of CH3+...Br-Y (Y=H, CCH, CN, NC) have been investigated by B3LYP/6- 311++G(d, p) and MP2/6-311++G(d, p) methods. The cal... Inverse halogen bonds interactions involving Br in the electronic deficiency systems of CH3+...Br-Y (Y=H, CCH, CN, NC) have been investigated by B3LYP/6- 311++G(d, p) and MP2/6-311++G(d, p) methods. The calculated interaction energies with basis set super-position error correction of the four IXBs complexes are 218.87, 219.48, 159.18, and 143.05kJ/mol (MP2/6-311++G(d, p)), respectively. The relative stabilities of the four complexes increased in the order: CH3+ … BrCN〈CH3+…- BrNC〈CH3+… BrH≈CH3+ …BrCCH. Natural bond orbital theory analysis and the chemical shifts calculation of the related atoms revealed that the charges flow from Br-Y to CH3e. Here, the Br of Br-Y acts as both a halogen bond donor and an electron donor. Therefore, compared with conventional halogen bonds, the IXBs complexes formed between Br-Y and CH3+. Atoms-in-molecules theory has been used to investigate the topological properties of the critical points of the four IXBs structures which have more covalent content. 展开更多
关键词 CH3+ Electronic deficiency system Inverse halogen bond Electron density topological property
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A Model for Mechanical Property Evaluation of the Periodic Porous Low-k Materials by SAW
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作者 李志国 姚素英 +1 位作者 肖夏 白茂森 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第11期1722-1728,共7页
The influence of the distribution of nano-pores on the mechanical properties evaluation of porous low-k films by surface acoustic waves (SAW) is studied. A theoretical SAW propagation model is set up to characterize... The influence of the distribution of nano-pores on the mechanical properties evaluation of porous low-k films by surface acoustic waves (SAW) is studied. A theoretical SAW propagation model is set up to characterize the periodic porous dielectrics by transversely isotropic symmetry. The theoretical deductions of SAW propagating in the low-k film/Si substrate layered structure are given in detail. The dispersive characteristics of SAW in differ- ent propagation directions and the effects of the Young's moduli E, E′ and shear modulus G′ of the films on these dispersive curves are found. Computational results show that E′ and G′ cannot be measured along the propagation direction that is perpendicular to the nano-pores' direction. 展开更多
关键词 periodic porous materials low-k dielectrics transversely isotropic symmetry mechanical proper ty SAW measurement
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Three-dimensional arbitrarily anisotropic modeling for time-domain airborne electromagnetic surveys 被引量:2
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作者 黄威 贲放 +5 位作者 殷长春 孟庆敏 李文杰 廖桂香 吴珊 西永在 《Applied Geophysics》 SCIE CSCD 2017年第3期431-440,462,共11页
Electrically anisotropic strata are abundant in nature, so their study can help our data interpretation and our understanding of the processes of geodynamics. However, current data processing generally assumes isotrop... Electrically anisotropic strata are abundant in nature, so their study can help our data interpretation and our understanding of the processes of geodynamics. However, current data processing generally assumes isotropic conditions when surveying anisotropic structures, which may cause discrepancies between reality and electromagnetic data interpretation. Moreover, the anisotropic interpretation of the time-domain airborne electromagnetic (TDAEM) method is still confined to one dimensional (1D) cases, and the corresponding three-dimensional (3D) numerical simulations are still in development. In this study, we expanded the 3D TDAEM modeling of arbitrarily anisotropic media. First, through coordinate rotation of isotropic conductivity, we obtained the conductivity tensor of an arbitrary anisotropic rock. Next, we incorporated this into Maxwell's equations, using a regular hexahedral grid of vector finite elements to subdivide the solution area. A direct solver software package provided the solution for the sparse linear equations that resulted. Analytical solutions were used to verify the accuracy and feasibility of the algorithm. The proven model was then applied to analyze the effects of arbitrary anisotropy in 3D TDAEM via the distribution of responses and amplitude changes, which revealed that different anisotropy situations strongly affected the responses of TDAEM. 展开更多
关键词 Three-dimensional time-domain airborne electromagnetic arbitrary anisotropy vector finite element
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Research of the electrical anisotropic characteristics of water-conducting fractured zones in coal seams 被引量:7
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作者 Su Ben-Yu Yue Jian-Hua 《Applied Geophysics》 SCIE CSCD 2017年第2期216-224,322,共10页
Water flooding disasters are one of the five natural coal-mining disasters that threaten the lives of coal miners. The main causes of this flooding are water-conducting fractured zones within coal seams. However, when... Water flooding disasters are one of the five natural coal-mining disasters that threaten the lives of coal miners. The main causes of this flooding are water-conducting fractured zones within coal seams. However, when resistivity methods are used to detect water-conducting fractured zones in coal seams, incorrect conclusions can be drawn because of electrical anisotropy within the water-conducting fractured zones. We present, in this paper, a new geo-electrical model based on the geology of water-conducting fractured zones in coal seams. Factors that influence electrical anisotropy were analyzed, including formation water resistivity, porosity, fracture density, and fracture surface roughness, pressure, and dip angle. Numerical simulation was used to evaluate the proposed electrical method. The results demonstrate a closed relationship between the shape of apparent resistivity and the strike and dip of a fracture. Hence, the findings of this paper provide a practical resistivity method for coal-mining production. 展开更多
关键词 water-conducting fractured zones in coal seams coalfield goaf electrical anisotropy surface roughness formation water resistivity formation pressure
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Performance optimization of electric power steering based on multi-objective genetic algorithm 被引量:2
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作者 赵万忠 王春燕 +1 位作者 于蕾艳 陈涛 《Journal of Central South University》 SCIE EI CAS 2013年第1期98-104,共7页
The vehicle model of the recirculating ball-type electric power steering (EPS) system for the pure electric bus was built. According to the features of constrained optimization for multi-variable function, a multi-obj... The vehicle model of the recirculating ball-type electric power steering (EPS) system for the pure electric bus was built. According to the features of constrained optimization for multi-variable function, a multi-objective genetic algorithm (GA) was designed. Based on the model of system, the quantitative formula of the road feel, sensitivity, and operation stability of the steering were induced. Considering the road feel and sensitivity of steering as optimization objectives, and the operation stability of steering as constraint, the multi-objective GA was proposed and the system parameters were optimized. The simulation results show that the system optimized by multi-objective genetic algorithm has better road feel, steering sensibility and steering stability. The energy of steering road feel after optimization is 1.44 times larger than the one before optimization, and the energy of portability after optimization is 0.4 times larger than the one before optimization. The ground test was conducted in order to verify the feasibility of simulation results, and it is shown that the pure electric bus equipped with the recirculating ball-type EPS system can provide better road feel and better steering portability for the drivers, thus the optimization methods can provide a theoretical basis for the design and optimization of the recirculating ball-type EPS system. 展开更多
关键词 vehicle engineering electric power steering multi-objective optimization genetic algorithm
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Analytical solution for electromagnetic scattering from a sphere of uniaxial left-handed material 被引量:7
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作者 耿友林 何赛灵 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第1期99-104,共6页
Based on the analytical solution of electromagnetic scattering by a uniaxial anisotropic sphere in the spectral domain, an analytical solution to the electromagnetic scattering by a uniaxial left-handed materials (LHM... Based on the analytical solution of electromagnetic scattering by a uniaxial anisotropic sphere in the spectral domain, an analytical solution to the electromagnetic scattering by a uniaxial left-handed materials (LHMs) sphere is obtained in terms of spherical vector wave functions in a uniaxial anisotropic LHM medium. The expression of the analytical solution contains only some one-dimensional integral which can be calculated easily. Numerical results show that Mie series of plane wave scattering by an isotropic LHM sphere is a special case of the present method. Some numerical results of electromagnetic scattering of a uniaxial anisotropic sphere by a plane wave are given. 展开更多
关键词 Electromagnetic scattering Uniaxial anisotropic LHM Spherical vector wave functions Radar cross section (RCS)
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High temperature plastic deformation behavior of non-oriented electrical steel 被引量:1
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作者 肖于德 李敏 +3 位作者 王伟 周娟 吴光亮 彭跃明 《Journal of Central South University》 SCIE EI CAS 2009年第1期25-31,共7页
High temperature plastic deformation behavior of non-orientated electrical steel was investigated by Gleeble 1500 thermo-mechanical simulator at strain rate of 0.01-10 s^-1 and high temperature of 500-1 200 ℃. The st... High temperature plastic deformation behavior of non-orientated electrical steel was investigated by Gleeble 1500 thermo-mechanical simulator at strain rate of 0.01-10 s^-1 and high temperature of 500-1 200 ℃. The stress level factor (a), stress exponent (n), structural factor (A) and activation energy (Q) of high temperature plastic deformation process of non-orientated electrical steel in different temperature ranges were calculated by the Arrhenius model. The results show that, with dynamic elevation of deformation temperature, phase transformation from α-Fe to γ-Fe takes place simultaneously during plastic deformation, dynamic recovery and dynamic recrystallization process, leading to an irregular change of the steady flow stress. For high temperature plastic deformation between 500 and 800 ℃, the calculated values of a, n, A, and Q are 0.039 0 MPa 1, 7.93, 1.9× 10^18 s^-1, and 334.8 kJ/mol, respectively, and for high temperature plastic deformation between 1 050 and 1 200 ℃, the calculated values of a, n, A, and Q are 0.125 8 MPa1, 5.29, 1.0 × 10^28 s^-1, and 769.9 kJ/mol, respectively. 展开更多
关键词 non-oriented electrical steel plastic deformation flow stress
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Study of Strange Quark Mass in CFL Phase
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作者 LI Xin Lü Xiao-Fu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5X期905-908,共4页
In this paper we introduce bilocal fields in the global color symmetry model and consider color and electrical neutrality conditions simultaneously to study the effect of strange quark mass Ms for the momentum-depende... In this paper we introduce bilocal fields in the global color symmetry model and consider color and electrical neutrality conditions simultaneously to study the effect of strange quark mass Ms for the momentum-dependent condensate of color-flavor locked phase. Consequently we find that there will be a quantum phase transition occurring. 展开更多
关键词 global color model color superconductivity
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Electrical conductivity effect on MHD mixed convection of nanofluid flow over a backward-facing step 被引量:4
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作者 SELIMEFENDIGIL Fatih OCAN CBAN Seda OTOP Hakan F. 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第5期1133-1145,共13页
In this study,magneto-hydrodynamics (MHD) mixed convection effects of Al2O3-water nanofluid flow over a backward-facing step were investigated numerically for various electrical conductivity models of nanofluids.A uni... In this study,magneto-hydrodynamics (MHD) mixed convection effects of Al2O3-water nanofluid flow over a backward-facing step were investigated numerically for various electrical conductivity models of nanofluids.A uniform external magnetic field was applied to the flow and strength of magnetic field was varied with different values of dimensionless parameter Hartmann number (Ha=0,10,20,30,40).Three different electrical conductivity models were used to see the effects of MHD nanofluid flow.Besides,five different inclination angles between 0°-90° is used for the external magnetic field.The problem geometry is a backward-facing step which is used in many engineering applications where flow separation and reattachment phenomenon occurs.Mixed type convective heat transfer of backward-facing step was examined with various values of Richardson number (Ri=0.01,0.1,1,10) and four different nanoparticle volume fractions (Ф=0.01,0.015,0.020,0.025) considering different electrical conductivity models.Finite element method via commercial code COMSOL was used for computations.Results indicate that the addition of nanoparticles enhanced heat transfer significantly.Also increasing magnetic field strength and inclination angle increased heat transfer rate.Effects of different electrical conductivity models were also investigated and it was observed that they have significant effects on the fluid flow and heat transfer characteristics in the presence of magnetic field. 展开更多
关键词 electrical conductivity nanofluids backward-facing step MHD flow mixed convection
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General solutions for special orthotropic piezoelectric media 被引量:1
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作者 李相勇 王敏中 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第3期335-339,共5页
This paper presents the forms of the general solution for general anisotropic piezoelectric media starting from the basic equations of piezoelasticity by using the operator method introduced by Lur’e (1964), and give... This paper presents the forms of the general solution for general anisotropic piezoelectric media starting from the basic equations of piezoelasticity by using the operator method introduced by Lur’e (1964), and gives the analytical form of the general solution for special orthotropic piezoelectric media. This paper uses the non-uniqueness of the general solution to obtain the generalized LHN solution and the generalized E-L solution for special orthotropic piezoelectric media. When the special orthotropic piezoelectric media degenerate to transversely piezoelectric media, the solution given by this paper degenerates to the solution for transversely isotropic piezoelectric media accordingly, so that this paper generalized the results in transversely isotropic piezoelectric media. 展开更多
关键词 Special orthotropic piezoelectric media LHN solution E-L solution
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Analytical Solution for Thermo-Electro-Elastic Problems of an Orthotropic Piezoelectric Hollow Cylinder Subjected to Various Loading
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作者 戴宏亮 王熙 戴庆华 《Journal of Shanghai Jiaotong university(Science)》 EI 2004年第4期34-40,共7页
An interpolation method was used to solve the Volterra integral equation of the second kind caused by interaction among thermal, electric and mechanical fields. The exact expressions for the transient responses of str... An interpolation method was used to solve the Volterra integral equation of the second kind caused by interaction among thermal, electric and mechanical fields. The exact expressions for the transient responses of stresses, electric displacement and electric potential in an orthotropic piezoelectric hollow cylinder were obtained by means of the finite integral transforms. From the sample numerical calculations, it is seen that the present method is suitable for an orthotropic piezoelectric hollow cylinder subjected to arbitrary thermal shock, mechanical load and transient electric excitation. The result can be used as a reference to solve other transient coupled problems of thermo-electro-elasticity. 展开更多
关键词 thermo-electro-elastic ORTHOTROPIC piezoelectric hollow cylinder transient
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Detection performance of azimuthal electromagnetic logging while drilling tool in anisotropic media 被引量:3
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作者 Wu Zhen-Guan Wang Lei +3 位作者 Fan Yi-Ren Deng Shao-Gui Huang Rui Xing Tao 《Applied Geophysics》 SCIE CSCD 2020年第1期1-12,167,共13页
Azimuthal electromagnetic(EM)logging while drilling(LWD)has been extensively used in high-angle and horizontal(HA/HZ)wells.However,due to the effects of formation anisotropy,accurate geosteering decision and formation... Azimuthal electromagnetic(EM)logging while drilling(LWD)has been extensively used in high-angle and horizontal(HA/HZ)wells.However,due to the effects of formation anisotropy,accurate geosteering decision and formation evaluations have become increasingly difficult.To quantitatively analyze the effect of anisotropy on tool responses and data processing,this paper investigates the sensitivity of EM LWD measurements to electric anisotropy and inversion accuracy via forward modeling and inversion.First,a sensitivity factor is defined to quantitatively analyze the sensitivity of the magnetic field components and synthetic signals to electric anisotropy.Then,azimuthal EM LWD responses in anisotropic layered formations are simulated,and the sensitivities to formation parameters for compensated and uncompensated tool configurations are comparatively analyzed.Finally,we discuss the effects of the inversion model on bed boundary inversion in anisotropic formations.Numerical simulation and inversion results show that azimuthal EM LWD can be significantly affected by electric anisotropy.Fortunately,by using a symmetrical compensation configuration,the sensitivity of the geosignals to electric anisotropy can be suppressed,and the boundary detection capability can be further enhanced.Anisotropy normally gives rise to separated resistivity curves and abnormal"horns";moreover,complicated nonlinear distortion can also arise in geosignals as the tool approaches a bed boundary.If anisotropy effects are ignored in the inversion process,the estimated bed boundary and formation resistivity are usually unreliable,which may mislead geosteering decisions. 展开更多
关键词 ANISOTROPY azimuthal electromagnetic LWD sensitivity INVERSION
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Physical Properties of Si_(2)Ge and SiGe_(2) in Hexagonal Symmetry:First-Principles Calculations
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作者 Ying-bo Zhao Shi-xuan Lin +1 位作者 Qing-yang Fan Qi-dong Zhang 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第3期551-561,I0003,共12页
We predict two novel group 14 element alloys Si_(2)Ge and SiGe_(2) in P6_(2)22 phase in this work through first-principles calculations.The structures,stability,elastic anisotropy,electronic and thermodynamic properti... We predict two novel group 14 element alloys Si_(2)Ge and SiGe_(2) in P6_(2)22 phase in this work through first-principles calculations.The structures,stability,elastic anisotropy,electronic and thermodynamic properties of these two proposed alloys are investigated systematically.The proposed P6_(2)22-Si_(2)Ge and P6_(2)22-SiGe_(2) have a hexagonal symmetry structure,and the phonon dispersion spectra and elastic constants indicate that these two alloys are dynamically and mechanically stable at ambient pressure.The elastic anisotropy properties of P6_(2)22-Si_(2)Ge and P6_(2)22-SiGe_(2) are examined elaborately by illustrating the surface constructions of Young’s modulus,the contour surfaces of shear modulus,and the directional dependence of Poisson’s ratio;the differences with their corresponding group 14 element allotropes P6_(2)22-Si_(3) and P6_(2)22-Ge_(3) are also discussed and compared.Moreover,the Debye temperature and sound velocities are analyzed to study the thermodynamic properties of the proposed P6_(2)22-Si_(2)Ge and P6_(2)22-SiGe_(2). 展开更多
关键词 Group 14 element alloys Stability Elastic anisotropy property Electronic property
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Secondary Structure and Neurotrophic Effect of a 33.1 kDa Specific Protein (SSP-33.1) in Spinal Sensory Ganglia
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作者 沈建英 俞庆声 +2 位作者 王琪 李泉 蒲小平 《Journal of Chinese Pharmaceutical Sciences》 CAS 2003年第2期106-111,共6页
Aim To analyze the secondary structure and neurotrophic effect of a specific protein in sensory neurons. Methods Comparison of the proteins expressed in the rat spinal sensory neurons and motor neurons was made by t... Aim To analyze the secondary structure and neurotrophic effect of a specific protein in sensory neurons. Methods Comparison of the proteins expressed in the rat spinal sensory neurons and motor neurons was made by two dimensional electrophoresis. One specific protein in sensory neurons was isolated and purified by DEAE Sephacel ion exchange chromatography and high performance liquid chromatography. A primary analysis of its secondary structure by circular dichroism, and its neurotrophic effects were investigated using the model of dorsal root ganglia(DRG) cultured in vitro . Results The molecular weight and isoelectric point of the protein were 33 1 kDa and 5 52, respectively. Its circular dichroism showed that there were 20 8% α helix, 54 8% β sheet, 7 3% turn, and 17 1% random coil in its secondary structure. Biological experiments showed that the protein could promote the neurite outgrowth of DRG. Conclusion A specific protein in spinal sensory tissue with molecular weight of 33 1 kDa has been purified. There is mainly β sheet in the secondary structure of the protein. And the protein has neurotrophic effects in the model of DRG. 展开更多
关键词 spinal sensory specific 33 1 kDa protein two dimensional electrophoresis high performance liquid chromatography circular dichroism neurotrophic effect
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