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基于“结”理论论治多囊卵巢综合征体会
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作者 张丽敏 马学琴 +3 位作者 马晓绘 马洋 刘金明 虎峻瑞 《甘肃中医药大学学报》 2023年第5期26-29,共4页
基于“结”理论分析多囊卵巢综合征的病因病机及证治方药,从而为临床论治多囊卵巢综合征提供新的思路。指出气结、血结、痰结是多囊卵巢综合征的重要病机,临证对于“气结”甚者,多予柴胡疏肝散加减以疏肝行气,气行则血痰自利;对于“血... 基于“结”理论分析多囊卵巢综合征的病因病机及证治方药,从而为临床论治多囊卵巢综合征提供新的思路。指出气结、血结、痰结是多囊卵巢综合征的重要病机,临证对于“气结”甚者,多予柴胡疏肝散加减以疏肝行气,气行则血痰自利;对于“血结”甚者,多予桂枝茯苓丸加减以活血化瘀、行气除痰;对于“痰结”甚者,多予苍附导痰丸加减以祛痰利水、行气活血。临证基于“结”理论辨治多囊卵巢综合征可取得较好的疗效,附典型病案1则以验证。 展开更多
关键词 多囊卵巢综合征 “结”理论 中医辨治 体会
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Three-dimensional Imaging of Multi-slice Spiral CT in Bronchial Artery Correlative Study on Blood Supply of Central Lung Cancer and Its Clinical Significance 被引量:4
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作者 李智勇 杨冬 +2 位作者 伍建林 黎庶 董天 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第1期40-42,67,共4页
Objective: To evaluate three-dimensional bronchial artery imaging charactersin central lung cancer and applied values with multi-slice spiral CT (MSCT) to provide theoreticalevidence on blood supply and intervention t... Objective: To evaluate three-dimensional bronchial artery imaging charactersin central lung cancer and applied values with multi-slice spiral CT (MSCT) to provide theoreticalevidence on blood supply and intervention therapy. Methods: Eighteen patients with central lungcancer underwent MSCT with real time helical thin-slice CT scanning. Three-dimensional bronchialartery reconstruction was done at the console work-station. The space anatomical characters ofbronchial artery were observed through different rotations. Results: For 6 cases, thethree-dimensional images of bronchial artery (33.33%) could exactly show the origins, the routes(lung inner segment and mediatism segment) and the diameters of bronchial arteries. Vision rate ofbronchial arteries was the highest in pulmonary artery stricture and truncation groups, and thevessels' diameter became larger apparently. These characters demonstrated blood supply of this kindof central lung cancer come from bronchial artery. Volume rendering images were the best ones amongthree-dimensional images. Conclusion: Three-dimensional imaging with MSCT in bronchial artery canreveal the anatomical characters of bronchial artery and provide theoretical evidence on bloodsupply and intervention therapy of central lung cancer. 展开更多
关键词 bronchial artery multi-slice spiral CT three-dimensional reconstruction ANGIOGRAPHY
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A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in aqueous solutions and its applications in binary and ternary aqueous solutions 被引量:1
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作者 杨学民 赵伟洁 +2 位作者 柴国明 郭汉杰 张强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第3期626-641,共16页
A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in ternary and binary strong electrolyte aqueous solution was developed based on the ion and molecule coexi... A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in ternary and binary strong electrolyte aqueous solution was developed based on the ion and molecule coexistence theory and verified in four kinds of binary aqueous solutions and two kinds of ternary aqueous solutions. The calculated mass action concentrations of structural units or ion couples in four binary aqueous solutions and two ternary solutions at 298.15 K have good agreement with the reported activity data from literatures after shifting the standard state and concentration unit. Therefore, the calculated mass action concentrations of structural units or ion couples from the developed universal thermodynamic model for ternary and binary aqueous solutions can be applied to predict reaction ability of components in ternary and binary strong electrolyte aqueous solutions. It is also proved that the assumptions applied in the developed thermodynamic model are correct and reasonable, i.e., strong electrolyte aqueous solution is composed of cations and anions as simple ions, H2O as simple molecule and other hydrous salt compounds as complex molecules. The calculated mass action concentrations of structural units or ion couples in ternary and binary strong electrolyte aqueous solutions strictly follow the mass action law. 展开更多
关键词 universal thermodynamic model mass action concentration activity ternary aqueous solution binary aqueous solution ion and molecule coexistence theory structural units ion couples components
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Theoretical Study on Dissociation Potential Energy Surface of Peroxynitric Acid
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作者 韦文美 郑仁慧 +2 位作者 吴允凯 杨帆 洪石 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第6期659-662,I0003,共5页
The lowest energy structures of peroxynitric acid have been studied with B3LYP/6-311+ G(2d,2p) method. The potential energy surfaces (PES) along the O-N and O-O bonds have been scanned at CCSD(T)/aug-cc-pVDZ le... The lowest energy structures of peroxynitric acid have been studied with B3LYP/6-311+ G(2d,2p) method. The potential energy surfaces (PES) along the O-N and O-O bonds have been scanned at CCSD(T)/aug-cc-pVDZ level, respectively. The calculated results show that on the O-N PES, the O3-N4 bond length of the loose transition state is 2.82A^° and the corresponding energy barrier is 25.6 kcal/mol, while on the O-O PES, the loose transition state with of O2-O3 bond length of 2.35A^° has the energy barrier of 37.4 kcal/mol. Thus the primary reaction path for peroxynitric acid is the dissociation into HO2 and NO2. 展开更多
关键词 Peroxynitric acid STRUCTURE Potential energy surface Theoretical study
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Computation of Diffusion Activation Energies of C, N in γFe 被引量:2
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作者 苏文勇 张瑞林 邵彬 《Journal of Beijing Institute of Technology》 EI CAS 2002年第1期105-108,共4页
A structure relaxation model based on the empirical electron theory of solids and molecules is developed to compute the diffusion active energies of C, N in γFe. First, adding a restriction, the lattice maintains rig... A structure relaxation model based on the empirical electron theory of solids and molecules is developed to compute the diffusion active energies of C, N in γFe. First, adding a restriction, the lattice maintains rigidity when solute atom migrates to the saddle point. In this step, the hybridization classes of every atom do not change. Then, the restriction is loosed and the atoms are relaxed under the coulomb repulsive forces. It is supposed that the energy needed in the first step would be compensated partly by the second step. In this way, the diffusion active energies of C, N in γFe are computed. Compared with the experiment data, the relative errors are less than 5%, which are good results in the computation of activation energy of diffusion. 展开更多
关键词 diffusion active energy empirical electron theory electronic structure
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Electronic structure and flotation behavior of complex mineral jamesonite 被引量:2
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作者 赵翠华 陈建华 +2 位作者 李玉琼 何茜 吴伯增 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第2期590-596,共7页
Electronic structures of complex mineral jamesonite were studied using density functional theory method together with their flotation behavior. The flotation behavior ofjamesonite is similar to that of stibnite, indic... Electronic structures of complex mineral jamesonite were studied using density functional theory method together with their flotation behavior. The flotation behavior ofjamesonite is similar to that of stibnite, indicating good floatability at pH below 6 and easy depression with NaOH, especially with lime. In weak alkaline condition, the flotation behavior ofjamesonite is close to that of galena. The coordination structure of Pb for jamesonite is more complex than that for galena. Sb in jamesonite possesses two coordinated modes, whereas Sb of stibnite is only 3-coordinated. Pb in galena is more active than that in jamesonite. Sb (3-coordination) in jamesonite is inactive, in contrast with that in stibnite. However, 4-coordination Sb in jamesonite is more active than 3-coordination Sb. HOMO orbitals of jamesonite and stibnite contain metal atoms, which contribute to the formation of adsorption configuration of CaOH^+ when there is lime; therefore, jamesonite and stibnite are easily depressed by lime. 展开更多
关键词 JAMESONITE electronic structure flotation behavior density functional theory
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Nestedness of bird assemblages in the karst forest fragments of southwestern Guangxi, China 被引量:3
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作者 李肇天 陆舟 +3 位作者 舒晓莲 蒋光伟 许亮 周放 《Chinese Birds》 CSCD 2013年第2期170-183,共14页
The limestone region in southwestern Guangxi contains the most typical karst landforms in the world. Due to their destruction, the original forests mainly survive in nature reserves in the form of fragmented areas. Fr... The limestone region in southwestern Guangxi contains the most typical karst landforms in the world. Due to their destruction, the original forests mainly survive in nature reserves in the form of fragmented areas. From June 2009 to September 2010 we conducted an investigation of 13 relatively isolated habitats or sites, selected from each of the 13 nature reserves in southwestern Guangxi, with the least amount of anthropological activity and the largest presence of the original vegetation, in order to study the distribution of birds on forest fragments. The distribution patterns of the birds and the factors which affect them were analyzed by using the 'BINMATNEST' software and the Spearman’s rank correlation analysis, to determine: 1) whether nested patterns of birds in the karst area of southwestern Guangxi exist or not and 2) which factors are correlated with the nested patterns and the effect of these factors on forming nested patterns. The results show that the birds had statistically significant nested patterns in the karst area and the specificity of the habitat of the birds had a significant effect on the nested patterns. We suggest possible reasons for these results, based on the characteristics of the seasonal tropical rain forests in the study area and on neutral theory. We also urgently recommend that close attention be paid to the protection of the diversity of the environment for birds in all fragmented habitats. 展开更多
关键词 BIRDS NESTEDNESS habitat fragmentation karst area neutral theory
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Electronic Structure Research on Lattice Stability of V, Nb, and Ta by Density Functional Theory
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作者 陶辉锦 万芳铭 陈伟民 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第1期69-72,I0002,共5页
The difference of energy and electronic structure of V, Nb, and Ta in different crystalline structures were investigated by different methods in density functional theory (DFT). Lattice constants, total energies, an... The difference of energy and electronic structure of V, Nb, and Ta in different crystalline structures were investigated by different methods in density functional theory (DFT). Lattice constants, total energies, and densities of states of these metals were calculated using the plane-wave pseudopotential method in DFT. Results were compared with those of projector augmented wave method, CALPHAD method, and experiments. Total energy and electronic structure analyses showed that valence electrons mostly transferred from s to p or d state, changing obviously with both the crystal structure and the elemental period number from V to Ta and leading to stronger cohesion, higher cohesive energy and more stable lattice of heavier metals. 展开更多
关键词 V NB TA Lattice stability Density functional theory
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Effect of Pressure on Electronic Structures and Optical Properties of Rocksalt InN
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作者 许明耀 徐明 +1 位作者 段满益 胡庆平 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第3期293-296,I0001,共5页
The electronic structures and optical properties of rocksalt indium nitride (INN) under pressure were studied using the first-principles calculation by considering the exchange and correlation potentials with the ge... The electronic structures and optical properties of rocksalt indium nitride (INN) under pressure were studied using the first-principles calculation by considering the exchange and correlation potentials with the generalized gradient approximation. The calculated lattice constant shows good agreement with the experimental value. It is interestingly found that the band gap energy Eg at the F or X point remarkably increases with increasing pressure, but Eg at the L point does not increase obviously. The pressure coefficient of Eg is calculated to be 44 meV/GPa at the F point. Moreover, the optical properties of rocksalt InN were calculated and discussed based on the calculated band structures and electronic density of states. 展开更多
关键词 Density functional theory Electronic structure Optical property Rocksalt InN
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X-ray and DFT Study of Glaucocalyxin A Compound with Cytotoxic Activity
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作者 王福东 汪涛 +2 位作者 吴安安 丁兰 汪汉卿 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第3期275-284,339,共11页
The title compound glaucocalyxin A (1) (Ta,14β-dihydroxy-ent-kaur-16-en-3,15-dione) iso- lated from the leaves of isodon excisoides was characterized by IR, 1H NMR, 13C NMR, 1H-1H COSY, HMQC, HMBC, and EIMS, and ... The title compound glaucocalyxin A (1) (Ta,14β-dihydroxy-ent-kaur-16-en-3,15-dione) iso- lated from the leaves of isodon excisoides was characterized by IR, 1H NMR, 13C NMR, 1H-1H COSY, HMQC, HMBC, and EIMS, and its crystal structure was determined by singlecrystal X-ray diffraction. The X-ray crystal structure revealed that the molecular backbone of the chosen crystal is a tetracyclic system, including three six-membered rings and a five- membered ring, and the three six-membered rings are in a chair-like conformation. The five-membered ring adopts a twisted envelope-like conformation, and its geometrical param- eters were compared with theoretical calculations at the B3LYP and HF level of theory. The molecules form extensive networks through the intra- and intermolecular hydrogen bonds. The experimental NMR data were interpreted with the aid of magnetic shielding constant calculations, by means of the GIAO (gauge-Including atomic orbitals) method. Calculated and experimental results were compared with a satisfactory level of agreement. Molecular electrostatic potential map was used in an attempt to identify key features of the diterpenoid glaucocalyxin A that is necessary for its activity. Calculations of molecular electrostatic po- tential and stabilization energies suggest that the protonation of glaucocalyxin A will be able to occur on carbonyl oxygen atoms. 展开更多
关键词 Isodon excisoides Glaucocalyxin A X-ray structure Density functional theory
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Application of PCA and HCA to the Structure-Activity Relationship Study of Fluoroquinolones 被引量:2
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作者 李小红 张现周 +2 位作者 程新路 杨向东 朱遵略 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第2期143-148,共6页
Density functional theory (DFT) was used to calculate molecular descriptors (properties) for 12 fluoro-quinolone with anti-S.pneumoniae activity. Principal component analysis (PCA) and hierarchical cluster analy... Density functional theory (DFT) was used to calculate molecular descriptors (properties) for 12 fluoro-quinolone with anti-S.pneumoniae activity. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were employed to reduce dimensionality and investigate in which variables should be more effective for classifying fluoroquinolones according to their degree of an-S.pneumoniae activity. The PCA results showed that the variables ELUMO, Q3, Q5, QA, logP, MR, VOL and △EHL of these compounds were responsible for the anti-S.pneumoniae activity. The HCA results were similar to those obtained with PCA.The methodologies of PCA and HCA provide a reliable rule for classifying new fluoroquinolones with antiS.pneumoniae activity. By using the chemometric results, 6 synthetic compounds were analyzed through the PCA and HCA and two of them are proposed as active molecules with anti-S.pneumoniae, which is consistent with the results of clinic experiments. 展开更多
关键词 Structure-activity relationship Density functional theory Principal component analysis Hierarchical cluster analysis
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DEVELOPMENT OF EXTRINSIC FABRY PEROT FIBER SENSOR AND ITS APPLICATION TO SMART MATERIALS
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作者 黄民双 梁大开 +1 位作者 邱浩 陶宝祺 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2000年第1期15-19,共5页
In the work of developing extrinsic fabry perot interferometric (EFPI), the key technology of polishing fiber optic endfaces and coating the multilayer of dielectric films on them is raised and resolved to settle the... In the work of developing extrinsic fabry perot interferometric (EFPI), the key technology of polishing fiber optic endfaces and coating the multilayer of dielectric films on them is raised and resolved to settle the disturbance and stability problem of EFPI, which simplifies the sensing system, improves the sensor performance and reduces the cost. In this paper, the relations between the output interferential light intensity and the F P cavity length are calculated based on the theory of mode field coupling. The EFPI fiber optic sensor is adhered to a distributed smart laminate beam to detect vibration frequency and axial strain value, the results coincident with the results tested by PZT. 展开更多
关键词 extrinsic fabry perot interferometric sensor smart structure mode field coupling theory strain measurement
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DFT Study on Molecular Structures and ROS Scavenging Mechanisms of Novel Antioxidants from Lespedeza Virgata
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作者 李敏杰 张良苗 +1 位作者 刘卫霞 陆文聪 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第2期173-180,I0003,共9页
The molecular structure and radical scavenging activity of three novel antioxidants from Lespedeza Virgata, lespedezavirgatol, lespedezavirgatal, and lespedezacoumestan, have been studied using density functional theo... The molecular structure and radical scavenging activity of three novel antioxidants from Lespedeza Virgata, lespedezavirgatol, lespedezavirgatal, and lespedezacoumestan, have been studied using density functional theory with the B3LYP and BhandHLYP methods. The optimized geometries of neutral, radical cation, radical and anion forms were obtained at the B3LYP/6-31G(d) level, in which it was found that all the most stable conformations contain intramolecular hydrogen bonds. The same results were obtained from the MP2 method. The homolytic O-H bond dissociation enthalpy and the adiabatic ionization potential of neutral and anion forms for the three new antioxidants and adiabatic electron affinity and H-atom affinity for hydroxyl radical, superoxide anion radical, and hydrogen peroxide radical were determined both in gas phase and in aqueous solution using IEF-PCM and CPCM model with UAHF or Bondi cavity. The antioxidant activities and reactive oxygen species scavenging mechanisms were then discussed, and the results obtained from different methods are consistent. Furthermore, the antioxidant activities are consistent with the experimental findings of the compounds under investigation. 展开更多
关键词 Molecular structure Reactive oxygen species scavenging mechanism Novel antioxidant Density functional theory
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Structural Investigation of Technetium-Diphosphonate Complex 99mTc-MDP
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作者 邱玲 林建国 +2 位作者 居学海 贡雪东 罗世能 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第3期295-304,I0003,共11页
Density functional theory method has been employed to investigate the structures of the prototypical technetium-labeled diphosphonate complex 99mTc-MDP, where MDP represents methylenediphosphonic acid. A total of 14 t... Density functional theory method has been employed to investigate the structures of the prototypical technetium-labeled diphosphonate complex 99mTc-MDP, where MDP represents methylenediphosphonic acid. A total of 14 trial structures were generated by allowing for the geometric, conformational, charge, and spin isomerism. Based on the optimized structures and calculated energies at the B3LYP/LANL2DZ level, two stable isomers were determined for the title complex. And they were further studied systematically in comparison with the experimental structure. The basis sets 6-31G*(LANL2DZ for Tc), 6-31G*(cc-pVDZ-pp for Tc), and DGDZVP have also been employed in combination with the B3LYP functional to study the basis set effect on the geometries of isomers. The optimized structures agree well with the available experimental data, and the bond lengths are more sensitive to the basis set than the bond angles. The charge distributions were studied by the Mulliken population analysis and natural bond orbital analysis. The results reflect a significant ligand-to-metal electron donation. 展开更多
关键词 RADIOPHARMACEUTICAL 99mTc-methylenediphosphonate Structural prediction Density functional theory Basis set effect
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Coupling Effect of Water and Phosphate on Economic Traits of Sugarcane 被引量:3
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作者 陆国盈 蒋明明 +4 位作者 韩世健 裴铁雄 汤雪莲 秦洪波 Guo-ying Ming-ming Shi-jian Tie-xiong Xue-lian Hong-bo 《Agricultural Science & Technology》 CAS 2010年第5期62-65,120,共5页
[Objective] The aim was to study the coupling effect of water and phosphate on economic traits of sugarcane. [Method] Taking sugarcane variety ROC22 as tested material,coupling effects of different levels of water sup... [Objective] The aim was to study the coupling effect of water and phosphate on economic traits of sugarcane. [Method] Taking sugarcane variety ROC22 as tested material,coupling effects of different levels of water supply quantity and different levels of phosphorus fertilizer on the yield and quality of sugarcane were studied. Among them,water supply quantity had 3 levels,that was,the water supply quantity per 10 days from the early tillering stage of sugarcane to the end of elongation was 199.5 m3/hm2 (A1),400.5 m3/hm2 (A2) and 600.0 m3/hm2 (A3),respectively; Phosphorus fertilizer as basic fertilizer had 4 levels:P2O5 0 kg/hm2 (B1),120 kg/hm2 (B2),240 kg/hm2 (B3) and 360 kg/hm2 (B4). [Result] Treatment A3B2 in water-fertilizer coupling was more suitable to improve economic traits of sugarcane. [Conclusion] The research results provide theoretical basis for the efficient utilization of water and phosphorus fertilizer in production of Guangxi sugarcane and the cultivation of high-yield and high-glucose sugarcane. 展开更多
关键词 Sugarcane Water Phosphorus fertilizer Water-phosphate coupling Economic traits
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Influence of features of natural soft clay on behaviour of embankment 被引量:5
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作者 尹振宇 M.Karstunen +1 位作者 王建华 余闯 《Journal of Central South University》 SCIE EI CAS 2011年第5期1667-1676,共10页
The influence of different features of natural soft clays,namely anisotropy,destructuration and viscosity,on modelling the time-dependent behaviour of Murro embankment was investigated.The newly developed elasto-visco... The influence of different features of natural soft clays,namely anisotropy,destructuration and viscosity,on modelling the time-dependent behaviour of Murro embankment was investigated.The newly developed elasto-viscoplastic models were enhanced for determining viscosity parameters in a straightforward way and adopted for the finite element analysis.The same set of common parameters determined from conventional triaxial and oedometer tests was employed for all models,with additional parameters required for representing different soil features.The finite element predictions by using models coupled with BIOT's consolidation theory were compared with each other and with field data for settlement,horizontal displacement and excess pore pressures.In addition,the stress paths under the embankment loading were also compared with each other to improve the understanding of the effect of different soil features.All simulations demonstrate that all three features significantly influence the predictions.As a consequence,accounting for soil features needs to be carefully considered when they are applied to a construction site. 展开更多
关键词 VISCOSITY ANISOTROPY destructuration soft clay EMBANKMENT viscoplastieity
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Differences of grain-refining effect of Sc and Ti additions in aluminum by empirical electron theory analysis 被引量:5
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作者 叶益聪 何良菊 李培杰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第3期465-470,共6页
The differences of grain-refining effect between Sc and Ti additions in aluminum,which cannot be substantially explained by traditional theories,were carefully studied.The empirical electron theory(EET) of solids and ... The differences of grain-refining effect between Sc and Ti additions in aluminum,which cannot be substantially explained by traditional theories,were carefully studied.The empirical electron theory(EET) of solids and molecules was employed to calculate the valence electron structures(VES) of Al3Ti and Al3Sc.The conclusions can be drawn that,in the two alloys Al-Ti and Al-Sc,the different valence electron structures of Al3Ti and Al3Sc and the consequent differences of growth habit of the two particles,and the different interfacial electron density between particles and matrix fundamentally lead to the differences of grain-refining effect between Sc and Ti additions on aluminum and make Sr the better grain-refiner of aluminum. 展开更多
关键词 grain refining empirical electron theory(EET) valence electron structure(VES) AL3SC AL3TI
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Simplified method for predicating consolidation settlement of soft ground improved by floating soil-cement column 被引量:12
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作者 龚晓南 田效军 胡文韬 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第7期2699-2706,共8页
A simplified method is presented for predicting consolidation settlement of soft ground improved by floating soil-cement column on the basis of double soil-layer consolidation theory. Combining the axisymmetric consol... A simplified method is presented for predicting consolidation settlement of soft ground improved by floating soil-cement column on the basis of double soil-layer consolidation theory. Combining the axisymmetric consolidation model and equal strain assumption, the governing equation was derived for the consolidation of clayey subsoil reinforced by soil-cement column. By modifying the boundary condition of the interface between the improved layer and underlying layer on seepage and pore-water pressure, the analytical solution of consolidation of soft ground improved by floating soil-cement column was developed under depth-dependent ramp load. The results of the parameter analysis of consolidation behavior show that the consolidation rate is closely related with the depth replacement ratio by the column and the permeability of upper layer. The influence of column-soil constrained modulus ratio and radius ratio of the influence zone to the column on consolidation is also affected by depth replacement ratio. The column-soil total stress ratio increases with time and approaches the final value accompanied with the dissipation of excess pore water pressure. 展开更多
关键词 axisymmetric consolidation model floating soil-cement column consolidation depth-dependent ramp load analytical solution
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Prediction of Breakdown Voltage of Asymmetric Linearly-Graded Junction by Equivalent Doping Profile Transformation Method
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作者 何进 张兴 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第2期183-187,共5页
This report describes an equivalent doping profile transformation method with which the avalanche breakdown voltage of the asymmetric linearly graded junction was analytically predicted.The maximum breakdown voltage a... This report describes an equivalent doping profile transformation method with which the avalanche breakdown voltage of the asymmetric linearly graded junction was analytically predicted.The maximum breakdown voltage and the different depletion layer extension on the diffused side and substrate side are demonstrated in the report.The report shows the equivalent doping profile method is valid to predict the breakdown voltage of the complex P N junction.The analytical results agree with the experimental breakdown voltage in comparison with the abrupt junction and symmetric linearly graded junction approximations. 展开更多
关键词 P N junction asymmetric linearly graded junction breakdown voltage depletion layer extension equivalent doping profile transformation
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Sanders' Mid-long Cylindrical Shell Theory and its Application to Ocean Engineering Structures 被引量:3
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作者 Shutao He (1) heshutao6105@163.com Yao Zhao (1) 《Journal of Marine Science and Application》 2012年第1期98-105,共8页
The cylindrical shell is one of the main structural parts in ocean engineering structures.These cylinders are mostly of medium length,which means that the radius of the cross section is significantly smaller than the ... The cylindrical shell is one of the main structural parts in ocean engineering structures.These cylinders are mostly of medium length,which means that the radius of the cross section is significantly smaller than the length of the cylindrical shell.From the viewpoint of the shell theory,they belong to the mid-long cylindrical shell category.To solve mechanical problems on this kind of structure,especially a cracked cylindrical shell,analysis based on shell theory is necessary.At present the generally used solving system for the mid-long cylindrical shell is too complicated,difficult to solve,and inapplicable to engineering.This paper introduced the Sanders' mid-long cylindrical shell theory which reduces the difficulty of the solution process,and will be suitable for solving problems with complicated boundary conditions.On this basis,the engineering applications of this theory were discussed in conjunction with the problem of a mid-long cylindrical shell having a circumferential crack.The solution process is simple,and the closed form solution can usually be found.In practical engineering applications,it gives satisfactory precision. 展开更多
关键词 mid-long cylindrical shell cylindrical shell theory circumferential crack ocean engineeringstructure
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