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Home Monitoring of Estrone-3-Glucuronide (E1-3G) Levels in Two Different Ovarian Stimulation Protocols: A Pilot Study
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作者 Iavor K. Vladimirov Desislava Tacheva +2 位作者 Evan Gatev Magdalena Rangelova Martin Vladimirov 《Open Journal of Obstetrics and Gynecology》 2024年第10期1640-1656,共17页
Background: Studies have shown a strong correlation between the growth of E2 in serum and estrone-3-glucuronide (E1-3G) in urine during ovarian stimulation. Thus, we developed theoretical models for using urinary E1-3... Background: Studies have shown a strong correlation between the growth of E2 in serum and estrone-3-glucuronide (E1-3G) in urine during ovarian stimulation. Thus, we developed theoretical models for using urinary E1-3G in ovarian stimulation and focused on their experimental verification and analysis. Methods: A prospective, observational pilot study was conducted involving 54 patients who underwent 54 cycles of ovarian stimulation. The goal was to establish the growth rate of urinary E1-3G during the course of stimulation and to determine the daily upper and lower limits of growth rates at which stimulation is appropriate and safe. Controlled ovarian stimulation was performed using two different stimulation protocols—an antagonist protocol in 25 cases and a progestin-primed ovarian stimulation protocol (PPOS) in 29 cases, with fixed doses of gonadotropins. From the second day of stimulation, patients self-measured their daily urine E1-3G levels at home using a portable analyzer. In parallel, a standard ultrasound follow-up protocol accompanied by a determination of E2, LH, and P levels was applied to optimally control stimulation. Results: The average daily growth rates in both groups were about 50%. The daily increase in E1-3G for the antagonist protocol ranged from 14% to 79%, while they were 28% to 79% for the PPOS protocol. Conclusion: This is the first study to analyze the dynamics of E1-3G in two different protocols and to estimate the limits of its increase during the entire course of the stimulation. The results confirm our theoretical model for the viability of using urinary E1-3G for monitoring ovarian stimulation. 展开更多
关键词 Ovarian stimulation Monitoring E1-3G Antagonist Protocol PPOS Protocol IVF ART
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基于加权TOPSIS法的PEG-rhG-CSF合理性评价
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作者 蔡芳 胡海锦 +2 位作者 林方 魏小娟 张进华 《中国医药科学》 2024年第12期90-94,共5页
目的建立聚乙二醇化重组人粒细胞刺激因子(PEG-rhG-CSF)合理性使用的评价标准,利用加权优劣解距离法(TOPSIS)对PEG-rhG-CSF进行评价,为临床合理使用提供参考依据。方法调取福州市第二医院2019年10月至2022年4月的出院病历,以PEG-rhG-CS... 目的建立聚乙二醇化重组人粒细胞刺激因子(PEG-rhG-CSF)合理性使用的评价标准,利用加权优劣解距离法(TOPSIS)对PEG-rhG-CSF进行评价,为临床合理使用提供参考依据。方法调取福州市第二医院2019年10月至2022年4月的出院病历,以PEG-rhG-CSF说明书为基础,参照相关指南、专家共识以及文献资料制订评价标准,采用加权TOPSIS法进行合理性评价。结果使用PEG-rhG-CSF的426份病历中,理想解相对接近度(C_(i))>80%共250例(占比58.69%),介于60%~80%的124例(占比29.11%),<60%的52例(占比12.21%)。主要不合理使用问题表现在适应证不适宜、给药时机不适宜、药物联用不适宜。结论基于TOPSIS法的合理性评价,综合考虑多个指标,可以反映药物使用过程中各个环节的使用情况,评价过程简便灵活,操作性强。评价结果显示福州市第二医院PEG-rhG-CSF的临床应用过程基本合理,但需要加大管理的力度,保证临床合理使用该类药物。 展开更多
关键词 聚乙二醇化重组人粒细胞刺激因子 中性粒细胞减少 优劣解距离法 合理性评价
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沁水盆地榆社-武乡区块深部煤层气赋存条件及开发甜点预测 被引量:4
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作者 李伟 申建 +2 位作者 李超 文稔东 苏育飞 《大庆石油地质与开发》 CAS 北大核心 2023年第4期9-19,共11页
沁水盆地榆社-武乡区块深部煤层气富集成藏受多因素耦合作用,深部条件的特殊性使其选区不能完全参照浅部地质评价技术,亟需从地质-工程角度对区块进行开发甜点区优选,满足实际生产需要。以3#煤层为目的层,从构造与水动力、地应力、煤储... 沁水盆地榆社-武乡区块深部煤层气富集成藏受多因素耦合作用,深部条件的特殊性使其选区不能完全参照浅部地质评价技术,亟需从地质-工程角度对区块进行开发甜点区优选,满足实际生产需要。以3#煤层为目的层,从构造与水动力、地应力、煤储层含气性、孔渗性、煤体结构及力学性质等条件出发,剖析深部煤层气富集特点,运用多层次模糊数学评价法对区块进行甜点优选。结果表明:3#煤层煤体结构以Ⅰ类原生结构煤为主,具有泊松比小、弹性模量大、脆度指数高、含气性良好的特点,煤层厚度0.25~5.19 m,平均1.59 m,含气量16.5~25.5 m^(3)/t,平均19.84 m^(3)/t;研究区褶皱与断层较为发育,煤层顶板岩性以泥岩为主,地下水径流条件差;深部地应力状态表现为σV(垂直压力)>σH(最大水平压力)>σh(最小水平压力);3#煤层属低孔、低渗储层,微小孔发育,渗透率平均为0.183×10^(-3)μm^(2);根据综合评价得分划分4类甜点区,其中区块中西部和L1302井附近为开发甜点区。研究成果对榆社-武乡区块深部煤层气下一步勘探开发具有指导意义。 展开更多
关键词 深部煤层气 含气性 储层可改造性 地质选区 多层次模糊数学评价法 榆社-武乡区块 沁水盆地
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A hyperbolic Lindstedt-Poincare method for homoclinic motion of a kind of strongly nonlinear autonomous oscillators 被引量:7
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作者 Y.Y.Chen S.H.Chen K.Y.Sze 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第5期721-729,共9页
A hyperbolic Lindstedt-Poincare method is presented to determine the homoclinic solutions of a kind of nonlinear oscillators, in which critical value of the homoclinic bifurcation parameter can be determined. The gene... A hyperbolic Lindstedt-Poincare method is presented to determine the homoclinic solutions of a kind of nonlinear oscillators, in which critical value of the homoclinic bifurcation parameter can be determined. The generalized Lienard oscillator is studied in detail, and the present method's predictions are compared with those of Runge-Kutta method to illustrate its accuracy. 展开更多
关键词 Lindstedt-Poincare method Hyperbolic function Nonlinear autonomous oscillator - Homoclinic orbit
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Optical fiber positioning based on four-quadrant detector with Gaussian fitting method 被引量:3
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作者 Jin-Sheng Liu Hua Zou +1 位作者 Mei-Ling Zhang Lin-Zheng Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第7期115-120,共6页
With the development of large-scale spectral surveys, fiber positioning technology has been developing rapidly. Because of the performance advantages of a four-quadrant(4Q) detector, a fiber positioning and real-tim... With the development of large-scale spectral surveys, fiber positioning technology has been developing rapidly. Because of the performance advantages of a four-quadrant(4Q) detector, a fiber positioning and real-time monitoring system based on the 4Q detector is proposed. The detection accuracy of this system is directly determined by the precision of the center of the spot. A Gaussian fitting algorithm based on the 4Q detector is studied and applied in the fiber positioning process to improve the calculated accuracy of the spot center. The relationship between the center position of the incident spot and the detector output signal is deduced. An experimental platform is built to complete the simulated experiment. Then we use the Gaussian fitting method to process experimental data, compare the fitting value with the theoretical one and calculate the corresponding error. 展开更多
关键词 INSTRUMENTATION detectors - methods data analysis - techniques imaging spectroscopy- telescopes
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Surface and Texture Properties of Tb-Doped Ceria-Zirconia Solid Solution Prepared by Sol-Gel Method 被引量:6
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作者 樊国栋 冯长根 张昭 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第1期42-47,共6页
The three-way catalysts (TWCs) promoters Ce0.6Zr0.4- x TbxO2-y were prepared by sol-gel method. BET surface areas analysis indicated that an increase of the dopant Tb content from x = 0.05 to x = 0.15 favors an incr... The three-way catalysts (TWCs) promoters Ce0.6Zr0.4- x TbxO2-y were prepared by sol-gel method. BET surface areas analysis indicated that an increase of the dopant Tb content from x = 0.05 to x = 0.15 favors an increase of surface area from 66.8 to 80.4 m^2· g^-1 compared with the undoped sample Ce0 .6oZr0.40O2 65.1 m^2·g^- 1 after calcination at 650℃. Transmission electron microscopy (TEM) observation indicated that the doped samples have a higher thermal stability. The XRD and Raman spectra confirmed that the Ce0.6Zr0.4-xTbxO2-y cubic solid solution is formed. XPS analysis revealed that Ce and Tb mainly existed in the form of Ce^4+ and Tb^3 + , and Zr existed in the form of Zr^4+ on the surface of the samples. The doped samples were homogenous in composition ; the introduction of Tb into the CeO2-ZrO2 promoters resuited in the formation of a solid solution, and the concentration of surface lattice oxygen was increased. 展开更多
关键词 Ce0.6Zr0.4 - xTbxO2 - y solid solution three-way catalysts sol-gel method surface and texture structure rare earths
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Construction of n-sided polygonal spline element using area coordinates and B-net method 被引量:4
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作者 Juan Chen Chong-Jun Li Wan-Ji Chen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第5期685-693,共9页
In general, triangular and quadrilateral elements are commonly applied in two-dimensional finite element methods. If they are used to compute polycrystalline materials, the cost of computation can be quite significant... In general, triangular and quadrilateral elements are commonly applied in two-dimensional finite element methods. If they are used to compute polycrystalline materials, the cost of computation can be quite significant. Polygonal elements can do well in simulation of the materials behavior and provide greater flexibility for the meshing of complex geometries. Hence, the study on the polygonal element is a very useful and necessary part in the finite element method. In this paper, an n-sided polygonal element based on quadratic spline interpolant, denoted by PS2 element, is presented using the triangular area coordinates and the B-net method. The PS2 element is conforming and can exactly model the quadratic field. It is valid for both convex and non-convex polygonal element, and insensitive to mesh distortions. In addition, no mapping or coordinate transformation is required and thus no Jacobian matrix and its inverse are evaluated. Some appropriate examples are employed to evaluate the performance of the proposed element. 展开更多
关键词 Finite element method n-sided polygonalelement - Bivariate spline interpolation The second ordercompleteness
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Multi-train modeling and simulation integrated with traction power supply solver using simplified Newton–Raphson method 被引量:5
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作者 Thanatchai Kulworawanichpong 《Journal of Modern Transportation》 2015年第4期241-251,共11页
Multi-train modeling and simulation plays a vital role in railway electrification during operation and planning phase. Study of peak power demand and energy consumed by each traction substation needs to be deter- mine... Multi-train modeling and simulation plays a vital role in railway electrification during operation and planning phase. Study of peak power demand and energy consumed by each traction substation needs to be deter- mined to verify that electrical energy flowing in its railway power feeding system is appropriate or not. Gauss-Seidel, conventional Newton-Raphson, and current injection methods are well-known and widely accepted as a tool for electrical power network solver in DC railway power supply study. In this paper, a simplified Newton-Raphson method has been proposed. The proposed method employs a set of current-balance equations at each electrical node instead of the conventional power-balance equation used in the conventional Newton-Raphson method. This concept can remarkably reduce execution time and computing complexity for multi-train simulation. To evaluate its use, Sukhumvit line of Bangkok transit system (BTS) of Thai- land with 21.6-km line length and 22 passenger stopping stations is set as a test system. The multi-train simulation integrated with the proposed power network solver is developed to simulate 1-h operation service of selected 5-min headway. From the obtained results, the proposed method is more efficient with approximately 18 % faster than the conventional Newton-Raphson method and just over 6 % faster than the current injection method. 展开更多
关键词 Newton-Raphson method Gauss-Seidelmethod - Current-balance equation Current injectionmethod Multi-train simulation Power supply study
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Left-sided vagus nerve stimulation improves cardiopulmonary resuscitation outcomes in rats as effectively as right-sided vagus nerve stimulation 被引量:2
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作者 Wei-jing Shao Ting-ting Shu +7 位作者 Shuang Xu Li-cai Liang Jehane Michael Le Grange Yu-ran Zhou He Huang Yu Cai Qing Zhang Peng Sun 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2021年第4期309-316,共8页
BACKGROUND: Our group previously reported that right-sided vagus nerve stimulation(RVNS) significantly improved outcomes after cardiopulmonary resuscitation(CPR) in a rat model of cardiac arrest(CA). However, whether ... BACKGROUND: Our group previously reported that right-sided vagus nerve stimulation(RVNS) significantly improved outcomes after cardiopulmonary resuscitation(CPR) in a rat model of cardiac arrest(CA). However, whether left-sided vagus nerve stimulation(LVNS) could achieve the same effect as RVNS in CPR outcomes remains unknown.METHODS: A rat model of CA was established using modified percutaneous epicardial electrical stimulation to induce ventricular fibrillation(VF). Rats were treated with LVNS or RVNS for 30 minutes before the induction of VF. All animals were observed closely within 72 hours after return of spontaneous circulation(ROSC), and their health and behavior were evaluated every 24 hours.RESULTS: Compared with those in the RVNS group, the hemodynamic measurements in the LVNS group decreased more notably. Vagus nerve stimulation(VNS) decreased the serum levels of tumor necrosis factor-alpha(TNF-α) and the arrhythmia score, and attenuated inflammatory infiltration in myocardial tissue after ROSC, regardless of the side of stimulation, compared with findings in the CPR group. Both LVNS and RVNS ameliorated myocardial function and increased the expression of α-7 nicotinic acetylcholine receptor in the myocardium after ROSC. Moreover, a clear improvement in 72-hour survival was shown with VNS pre-treatment, with no significant difference in efficacy when comparing the laterality of stimulation. CONCLUSIONS: LVNS may have similar effects as RVNS on improving outcomes after CPR. 展开更多
关键词 Vagus nerve stimulation Cardiac arrest Tumor necrosis factor-alpha Myocardial function α-7 nicotinic acetylcholine receptor
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A hybrid vertex-centered finite volume/element method for viscous incompressible flows on non-staggered unstructured meshes 被引量:1
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作者 Wei Gao Ru-Xun Liu Hong Li 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第2期324-334,共11页
This paper proposes a hybrid vertex-centered fi- nite volume/finite element method for solution of the two di- mensional (2D) incompressible Navier-Stokes equations on unstructured grids. An incremental pressure fra... This paper proposes a hybrid vertex-centered fi- nite volume/finite element method for solution of the two di- mensional (2D) incompressible Navier-Stokes equations on unstructured grids. An incremental pressure fractional step method is adopted to handle the velocity-pressure coupling. The velocity and the pressure are collocated at the node of the vertex-centered control volume which is formed by join- ing the centroid of cells sharing the common vertex. For the temporal integration of the momentum equations, an im- plicit second-order scheme is utilized to enhance the com- putational stability and eliminate the time step limit due to the diffusion term. The momentum equations are discretized by the vertex-centered finite volume method (FVM) and the pressure Poisson equation is solved by the Galerkin finite el- ement method (FEM). The momentum interpolation is used to damp out the spurious pressure wiggles. The test case with analytical solutions demonstrates second-order accuracy of the current hybrid scheme in time and space for both veloc- ity and pressure. The classic test cases, the lid-driven cavity flow, the skew cavity flow and the backward-facing step flow, show that numerical results are in good agreement with the published benchmark solutions. 展开更多
关键词 Incompressible flow Vertex-centered finite vol- ume method Finite element method - Unstructured grid
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A meshfree-based local Galerkin method with condensation of degree of freedom for elastic dynamic analysis 被引量:1
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作者 De-An Hu Yi-Gang Wang +2 位作者 Yang-Yang Li Xu Han Yuan-Tong Gu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第1期92-99,共8页
Condensation technique of degree of freedom is first proposed to improve the computational efficiency of meshfree method with Galerkin weak form for elastic dy- namic analysis. In the present method, scattered nodes w... Condensation technique of degree of freedom is first proposed to improve the computational efficiency of meshfree method with Galerkin weak form for elastic dy- namic analysis. In the present method, scattered nodes with- out connectivity are divided into several subsets by cells with arbitrary shape. Local discrete equation is established over each cell by using moving Kriging interpolation, in which the nodes that located in the cell are used for approxima- tion. Then local discrete equations can be simplified by con- densation of degree of freedom, which transfers equations of inner nodes to equations of boundary nodes based on cells. The global dynamic system equations are obtained by as- sembling all local discrete equations and are solved by using the standard implicit Newmark's time integration scheme. In the scheme of present method, the calculation of each cell is carried out by meshfree method, and local search is imple- mented in interpolation. Numerical examples show that the present method has high computational efficiency and good accuracy in solving elastic dynamic problems. 展开更多
关键词 Meshfree method Local Galerkin method Moving Kriging interpolation - Condensation of degree of freedom Computational efficiency
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Short-term solar flare prediction using multi-model integration method 被引量:1
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作者 Jin-Fu Liu Fei Li +1 位作者 Jie Wan Da-Ren Yu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第4期23-34,共12页
A multi-model integration method is proposed to develop a multi-source and heterogeneous model for short-term solar flare prediction. Different prediction models are constructed on the basis of extracted predictors fr... A multi-model integration method is proposed to develop a multi-source and heterogeneous model for short-term solar flare prediction. Different prediction models are constructed on the basis of extracted predictors from a pool of observation databases. The outputs of the base models are normal- ized first because these established models extract predictors from many data resources using different prediction methods. Then weighted integration of the base models is used to develop a multi-model integrated model (MIM). The weight set that single models assign is optimized by a genetic algorithm. Seven base models and data from Solar and Heliospheric Observatory/Michelson Doppler Imager lon- gitudinal magnetograms are used to construct the MIM, and then its performance is evaluated by cross validation. Experimental results showed that the MIM outperforms any individual model in nearly every data group, and the richer the diversity of the base models, the better the performance of the MIM. Thus, integrating more diversified models, such as an expert system, a statistical model and a physical model, will greatly improve the performance of the MIM. 展开更多
关键词 methods: statistical - Sun activity - Sun' magnetic fields - Sun' photosphere - Sun FLARES
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A class of fully third-order accurate projection methods for solving the incompressible Navier-Stokes equations 被引量:2
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作者 Yuxin Ren Yuxi Jiang +1 位作者 Miao'er Liu Hanxin Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2005年第6期542-549,共8页
In this paper, a fully third-order accurate projection method for solving the incompressible Navier-Stokes equations is proposed. To construct the scheme, a continuous projection procedure is firstly presented. We the... In this paper, a fully third-order accurate projection method for solving the incompressible Navier-Stokes equations is proposed. To construct the scheme, a continuous projection procedure is firstly presented. We then derive a sufficient condition for the continuous projection equations to be temporally third-order accurate approximations of the original Navier-Stokes equations by means of the localtruncation-error-analysis technique. The continuous projection equations are discretized temporally and spatially to third-order accuracy on the staggered grids, resulting in a fully third-order discrete projection scheme. The possibility to design higher-order projection methods is thus demonstrated in the present paper. A heuristic stability analysis is performed on this projection method showing the probability of its being stable. The stability of the present scheme is further verified through numerical tests. The third-order accuracy of the present projection method is validated by several numerical test cases. 展开更多
关键词 Incompressible Navier-Stokes equations Projection methods - Third-order scheme - Local truncation error
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Pseudo-beam method for compressive buckling characteristics analysis of space inflatable load-carrying structures 被引量:1
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作者 Changguo Wang Huifeng Tan Xingwen Du Center for Composite Materials,Harbin Institute of Technology, 150001 Harbin, China 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第5期659-668,共10页
This paper extends Le van's work to the case of nonlinear problem and the complicated configuration. The wrinkling stress distribution and the pressure effects are also included in our analysis. Pseudo-beam method is... This paper extends Le van's work to the case of nonlinear problem and the complicated configuration. The wrinkling stress distribution and the pressure effects are also included in our analysis. Pseudo-beam method is presented based on the inflatable beam theory to model the inflatable structures as a set of inflatable beam elements with a prestressed state. In this method, the discretized nonlinear equations are given based upon the virtual work principle with a 3-node Timoshenko's beam model. Finite element simulation is performed by using a 3-node BEAM189 element incorporating ANSYS nonlinear program. The pressure effect is equivalent included in our method by modifying beam element cross-section parameters related to pressure. A benchmark example, the bending case of an inflatable cantilever beam, is performed to verify the accuracy of our proposed method. The comparisons reveal that the numerical results obtained with our method are close to open published analytical and membrane finite element results. The method is then used to evaluate the whole buckling and the loadcarrying characteristics of an inflatable support frame subjected to a compression force. The wrinkling stress and region characteristics are also shown in the end. This method gives better convergence characteristics, and requires much less computation time. It is very effective to deal with the whole load-carrying ability analytical problems for large scale inflatable structures with complex configuration. 展开更多
关键词 Inflatable structure - Pseudo-beam method Inflatable beam theory Nonlinear buckling finite element
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Two 8-node quadrilateral spline elements by B-net method 被引量:1
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作者 Juan Chen Chong-Jun Li 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第6期1620-1629,共10页
Isoparametric quadrilateral elements are widely used in the finite element method, but the accuracy of the isoparametric quadrilateral elements will drop obviously deteriorate due to mesh distortions. Spline functions... Isoparametric quadrilateral elements are widely used in the finite element method, but the accuracy of the isoparametric quadrilateral elements will drop obviously deteriorate due to mesh distortions. Spline functions have some properties of simplicity and conformality. Two 8-node quadrilateral elements have been developed using the trian- gular area coordinates and the B-net method, which can ex- actly model the quadratic field for both convex and concave quadrangles. Some appropriate examples are employed to evaluate the performance of the proposed elements. The nu- merical results show that the two spline elements can obtain solutions which are highly accurate and insensitive to mesh distortions. 展开更多
关键词 Spline finite element B-net method Quadri-lateral element - Bivariate spline interpolation The secondorder completeness
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Preparation of BaCe_(0.5)Zr_(0.4)Y_(0.1)O_(3-α) by Sol-Gel Method and Its Electrical Properties 被引量:1
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作者 Wang Jie Ding Weizhong +2 位作者 Fang Jianhui Zhu Dongdong Wu Minyan 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第4期454-454,共1页
A precursor of BaCe0.5Zr0.4Y0. 1O3-α electrolytes was synthesized by the sol-gel method and sintered at temperature which were 150 - 250 ℃ lower than by solid state reaction. The AC impedance spectrums of electrolyt... A precursor of BaCe0.5Zr0.4Y0. 1O3-α electrolytes was synthesized by the sol-gel method and sintered at temperature which were 150 - 250 ℃ lower than by solid state reaction. The AC impedance spectrums of electrolytes were measured by AUTOLAB PGSTA30 electrochemical measuring device at different temperatures. The conductivities of the electrolytes are 1.62×10^-4 - 6.43×10^-3, 2.52×10^-5 - 3.73×10^-3S·cm^-1 in the temperature range of 350-800℃. The activity energies are 0.54 and 0.84 eV. At the same time BaCe0.9Y0.1O3-α was prepared by direct solid state reaction. The conductivity of BaCe0.9Y0.1O3-α is 1 × 10^-4- 4×10^-3 S·cm^-1 and the activation energy is 0.50 eV at the same condition. The results show that conduction of electrolyte prepared by sol-gel method is higher than the one by solid state reaction. As far as BaCe0.9Y0.1O3-α concerned, its conductivity of the Zr-substituted specimens is decreased. 展开更多
关键词 BaCe0.5Zr0.4Y0.1O3-α solid electrolyte sol-gel method CONDUCTIVITY activation energies solid-state reaction rare earths
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基于Test Method 1311法重结晶α-半水石膏重金属元素的浸出特性研究 被引量:1
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作者 余智 吴晓琴 +1 位作者 许勇 叶智 《安全与环境工程》 CAS 2017年第5期94-99,共6页
以脱硫石膏及其常压盐溶液法重结晶得到的α-半水石膏为研究对象,采用改进的Tessier流程和Test Method 1311法研究两种石膏晶体重金属元素的赋存形态和浸出特性,并对其进行环境效应评价。结果表明:重结晶过程能够释放脱硫石膏中的重金... 以脱硫石膏及其常压盐溶液法重结晶得到的α-半水石膏为研究对象,采用改进的Tessier流程和Test Method 1311法研究两种石膏晶体重金属元素的赋存形态和浸出特性,并对其进行环境效应评价。结果表明:重结晶过程能够释放脱硫石膏中的重金属元素并使其赋存形态改变;重结晶后石膏晶体中的重金属组分短期内可达到释放平衡,其中Cr、Pb、Ni元素的最大浸出量明显低于对应的脱硫石膏,As元素的浸出量几乎不变;α-半水石膏的环境友好性优于脱硫石膏,但仍具有污染环境的潜在风险。 展开更多
关键词 脱硫石膏 Α-半水石膏 重结晶 Test method 1311法 重金属元素 赋存形态 浸出特性
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Microwave absorption properties regulation and bandwidth formula of oriented Y_(2)Fe_(17)N_(3-δ)@SiO_(2)/PU composite synthesized by reduction-diffusion method 被引量:1
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作者 Hao Wang Liang Qiao +4 位作者 Zu-Ying Zheng Hong-Bo Hao Tao Wang Zheng Yang Fa-Shen Li 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第11期341-351,共11页
As concepts closely related to microwave absorption properties,impedance matching and phase matching were rarely combined with material parameters to regulate properties and explore related mechanisms.In this work,red... As concepts closely related to microwave absorption properties,impedance matching and phase matching were rarely combined with material parameters to regulate properties and explore related mechanisms.In this work,reduction–diffusion method was innovatively applied to synthesize rare earth alloy Y_(2)Fe_(17).In order to regulate the electromagnetic parameters of absorbers,the Y_(2)Fe_(17)N_(3-δ)particles were coated with silica(Y_(2)Fe_(17)N_(3-δ)@SiO_(2))and absorbers with different volume fractions were prepared.The relationship between impedance matching,matching thickness,and the strongest reflection loss peak(RLmin)was presented obviously.Compared to the microwave absorption properties of Y_(2)Fe_(17)N_(3-δ)/PU absorber,Y_(2)Fe_(17)N_(3-δ)@SiO_(2)/PU absorbers are more conducive to the realization of microwave absorption material standards which are thin thickness,light weight,strong absorbing intensity,and broad bandwidth.Based on microwave frequency bands,the microwave absorption properties of the absorbers were analyzed and the related parameters were listed.As an important parameter related to perfect matching,reflection factor(√ε_(r)/μ_(r))was discussed combined with microwave amplitude attenuation.According to the origin and mathematical model of bandwidth,the formula of EAB(RL<-10 dB)was derived and simplified.The calculated bandwidths agreed well with experimental results. 展开更多
关键词 microwave absorption rare earth alloy reduction-diffusion method Y_(2)Fe_(17)N_(3-δ)@SiO_(2) reflection factor impedance and phase matching bandwidth formula
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Analytical and Traveling Wave Solutions to the Fifth Order Standard Sawada-Kotera Equation via the Generalized exp(-Φ(ξ))-Expansion Method 被引量:1
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作者 M. Y. Ali M. G. Hafez +1 位作者 M. K. H. Chowdury M. T. Akter 《Journal of Applied Mathematics and Physics》 2016年第2期262-271,共10页
In this article, we propose a generalized exp(-Φ(ξ))-expansion method and successfully implement it to find exact traveling wave solutions to the fifth order standard Sawada-Kotera (SK) equation. The exact traveling... In this article, we propose a generalized exp(-Φ(ξ))-expansion method and successfully implement it to find exact traveling wave solutions to the fifth order standard Sawada-Kotera (SK) equation. The exact traveling wave solutions are established in the form of trigonometric, hyperbolic, exponential and rational functions with some free parameters. It is shown that this method is standard, effective and easily applicable mathematical tool for solving nonlinear partial differential equations arises in the field of mathematical physics and engineering. 展开更多
关键词 Generalized exp(-Φ(ξ))-Expansion method Fifth Order Standard Sawada-Kotera Equation SOLITONS Periodic Wave Solutions
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SELECTING CLUSTER MODEL IN Sn - BASED SOLDER ALLOY DESIGN WITH DV - X_α CALCULATION METHOD
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作者 C. Q. Wang and W. F. Feng National ho. of Advanced welding Technolgy, HIT, Harbin 150001,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第1期84-88,共5页
Applying calculation method in alloy design should be an important tendency due to its characters of inexpensive cost, high efficiency and prediction. DOS calculations of AuSn, AsSn and SbSn Sn- based alloys have ... Applying calculation method in alloy design should be an important tendency due to its characters of inexpensive cost, high efficiency and prediction. DOS calculations of AuSn, AsSn and SbSn Sn- based alloys have been investigated by employing DV - Xa method, in which different cluster models were adopted to calculate electron structure.It is proved that some regulations must be taken into ac- count in order to carry out alloy design calculation successfully,which are described in this paper in detail. 展开更多
关键词 Cluster model Sn - based alloy design DV - X_a calculation method DOS
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