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Efficacy of local aspiration in the conservative treatment of live interstitial pregnancy coexisting with live intrauterine pregnancy after in vitro fertilization and embryo transfer

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Chinese Medical Journal 2012年第7期125卷 1345-1348页

作者： WANG Yang MA Cai-hong QIAO jie CHEN Xin-na LIU ping Center for Reproductive Medicine Peking University Third HospitalBeijing 100191China

Background Heterotopic pregnancy （HP） is defined as a pregnancy in which one or more embryos is viably implanted in the uterus while the other is implanted elsewhere as an ectopic pregnancy. The occurrence of HP rises dramatically with the increased use of assisted reproductive technology. HP of interstitial pregnancy is one special situation which needs more concern. Here we evaluate the efficacy of local aspiration and instillation of hyperosmolar glucose in the treatment of live interstitial pregnancy complicated with live intrauterine pregnancy after in vitro fertilization and embryo transfer. Methods Five female patients were diagnosed with live interstitial pregnancies complicated with intrauterine pregnancies. They were treated with transvaginal ultrasound-guided aspiration of interstitial pregnancy and instillation of hyperosmolar glucose at the Center for Reproductive Medicine of Peking University Third Hospital from January 1st, 2008 to May 30th, 2011. Results Gemmule embryos in all 5 cases were aspirated successfully and there was no abdominal hemorrhage, threatened abortion or infection in any of the cases. The sac of interstitial pregnancy continued to progress after aspiration and stopped growing between 11 to 20 weeks. By the 30th week of pregnancy, 80% of the interstitial masses had disappeared. Four cases have delivered and one is still in on-going pregnancy. All of the four cases underwent cesarean section and there were nothing special detected in the corner of the uterus. Conclusion Local aspiration and instillation of hyperosmolar glucose may be an effective way to treat live interstitial pregnancy when coexisting with a live intrauterine pregnancy.

关键词： interstitial pregnancy heterotopic pregnancy fetocide in vitro fertilization,"transvaginal ultrasound-guided aspiration

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Ultrahigh performance concrete–properties, applications and perspectives

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Science China(Technological Sciences) 2015年第4期58卷 587-599页

作者： GU Chun ping YE Guang SUN Wei School of Materials Science & Engineering Southeast University Microlab Faculty of Civil Engineering and Geosciences Delft University of Technology Jiangsu Key Laboratory of Construction Materials Collaborative Innovation Center for Advanced Civil Engineering Materials

Over the last twenty years,remarkable advances have taken place in the research and application of ultra-high performance concrete(UHPC),which exhibits outstanding mechanical properties and excellent *** has shown great potential for the next generation infrastructure construction from the sustainability point of *** paper will give an overview on UHPC,with particular focus on the properties,applications and *** several decades of development,several types of commercial UHPC materials are available in the market,and the properties of UHPC have been characterized by numerous experimental and field *** speaking,the performance(*** properties and durability)of UHPC is much better than normal concrete(NC)and high performance concrete(HPC).Therefore,the uses of UHPC are growing all over the world,in both fields of new construction and ***,it is still a special material and technology,which is not worldwide *** some application prospects of UHPC are briefly introduced in the paper,and the efforts,which have to be made to turn UHPC into a widespread‘regular’technology,are *** paper aims to help designers,engineers,architects and infrastructure owners to know the capacities of UHPC and thus to increase the applications of this material.

关键词： UHPC characteristics durability applications perspectives

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From microscopic theory to macroscopic theory——symmetries and order parameters of rigid molecules

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Science China Mathematics 2014年第3期57卷 443-468页

作者： XU jie ZHANG pingWen LMAM and School of Mathematical Sciences Peking University

Density functional theory is used to describe the phase behaviors of rigid molecules. The construc- tion of the kernel function is discussed. Excluded-volume potential is calculated for two types of molecules with C2v symmetry. Molecular symmetries lead to the symmetries of the kernel function and the density function, enabling a reduction of configuration space. By approximating the kernel function with a polynomial, the system can be fully characterized by some moments corresponding to the form of the kernel function. The symmetries of the kernel function determine the form of the polynomial, while the coefficients are determined by the tem- perature and molecular parameters. The analysis of the impact of coefficients helps us to choose independent variables in the moments as order parameters. Combining the analysis and some simulation results, we propose a minimal set of order parameters for bent-core molecules.

关键词： liquid crystals symmetry order parameter bent-core molecules excluded volume

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Impact of Household Endowments on Response Capacity of Farming Households to Natural Disasters

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International Journal of Disaster Risk Science 2012年第4期3卷 218-226页

作者： Haixia Zhang Tianhui Zhuang Weizhong zeng College of Economics and Management Sichuan Agricultural University Chengdu 611130 China

This article investigates the impact of household endowments on household’s ability to cope with natural disaster risks and the determining factors of disaster coping capacity. We present results of a research based on household survey. The data were analyzed with an ordered Probit model regression. The project surveyed 923 rural households in 2009 and 2010 in 39 national-level poverty-stricken counties of Sichuan, Yunnan, and Guizhou Provinces and Chongqing Municipality. This research determined that the economic strength of households is the most important factor affecting their disaster coping capacity. The ability of farming households to cope with disasters is also significantly impacted by family members’ experiences and their economic context at the village level. Ethnic minority areas in southwestern China are the poorest in the country and are often the main disasteraffected areas. Since household endowments significantly affect the ability of farming households to cope with disasters, integration of disaster risk management and poverty reduction is a viable way of enhancing coping capacity of farming households to natural disasters.

关键词： disaster Impact Chongqing

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Effect of densification distribution on the Young's modulus of porous coatings after nano-indentation

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Acta Metallurgica Sinica(English Letters) 2012年第5期25卷 383-390页

作者： Xiaojuan L U ping XIAO Haiyan LI School of Environment Science and Engineering North China Electric Power University Yonghua North Street Baoding 071000 China School of Materials The University of Manchester Manchester M1 7HS UK School of Mechanical Aerospace and Civil Engineering The University of Manchester P.O. Box 88Sackville Street Manchester M60 1QD UK

Nano-indentation of a porous ceramic coating leads to crushing and densification of the coating under the indenter. In this work, finite element simulations of indentation on the porous coating have been carried out to study the effect of the size and dis- tribution of densification on Youngts modulus measured by nano-indentation. Two totally different distribution patterns have been simulated in this work. In the case of gradient densification, the Youngts modulus increased by 8.6% when the densifi- cation has occurred in the maximum influenced area. While the Young^s modulus increased by 2% with a uniformed densification. Examinations of the cross-section of the coatings have suggested that the densification after the indentation is close to the second model. The measured Young＇s modulus could have differed by 2%. The effect of densification on the Young＇s modulus measured by using nano-indentation is strongly dependent on the densification patterns of the porous coating.

关键词： Film Mechanical property Finite element simulation Porosity Electron Microscopy

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Multi-objective particle swarm optimization algorithm using Cauchy mutation and improved crowding distance

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International Journal of Intelligent Computing and Cybernetics 2023年第2期16卷 250-276页

作者： Qingxia Li Xiaohua zeng Wenhong Wei School of Computer and Information Dongguan City CollegeDongguanChina School of Economics and Trade Guangzhou Xinhua UniversityDongguanChina School of Computer Dongguan University of TechnologyDongguanChina

Purpose-Multi-objective is a complex problem that appears in real life while these objectives are *** swarm intelligence algorithm is often used to solve such multi-objective *** to its strong search ability and convergence ability,particle swarm optimization algorithm is proposed,and the multi-objective particle swarm optimization algorithm is used to solve multi-objective optimization ***,the particles of particle swarm optimization algorithm are easy to fall into local optimization because of their fast *** distribution and poor diversity are the two key drawbacks of the Pareto front of multi-objective particle swarm optimization ***,this paper aims to propose an improved multi-objective particle swarm optimization algorithm using adaptive Cauchy mutation and improved crowding ***/methodology/approach-In this paper,the proposed algorithm uses adaptive Cauchy mutation and improved crowding distance to perturb the particles in the population in a dynamic way in order to help the particles trapped in the local optimization jump out of it which improves the convergence performance ***-In order to solve the problems of uneven distribution and poor diversity in the Pareto front of multi-objective particle swarm optimization algorithm,this paper uses adaptive Cauchy mutation and improved crowding distance to help the particles trapped in the local optimization jump out of the local *** results show that the proposed algorithm has obvious advantages in convergence performance for nine benchmark functions compared with other multi-objective optimization ***/value-In order to help the particles trapped in the local optimization jump out of the local optimization which improves the convergence performance consequently,this paper proposes an improved multi-objective particle swarm optimization algorithm using adaptive Cauchy mutation and imp

关键词： Particle swarm optimization Cauchy variation Crowding distance Multi-objective Pareto

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Kinetics and Mechanism Modeling of Liquid-Phase Toluene Oxidation to Benzaldehyde Catalyzed by Mn–Mo Oxide

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Transactions of Tianjin University 2019年第1期25卷 52-65页

作者： Wang Li Qingjun Zhang Aiwu zeng School of Chemical Engineering and Technology Tianjin University

In this study, liquid-phase aerobic oxidation of toluene catalyzed by Mn–Mo oxide was conducted in a 1.0 L batch reactor. The macroscopic kinetics of toluene consumption and benzaldehyde generation at 413–443 K were obtained from a combination of experimental observation and hypothetical models. The results clearly showed that both the oxidation rate of toluene and generation rate of the aromatic product were proportional to the concentration of the substrate, the partial pressure of oxygen and the surface area of the catalyst. The energy barrier of toluene oxidation to benzyl alcohol was the highest(≈ 81 kJ mol^(-1)), while that of benzyl alcohol oxidation to benzaldehyde was the lowest(≈ 57 kJ mol^(-1)). Moreover, the activation energy of further oxidation of benzaldehyde in an acetic acid solvent was only slightly lower(≈ 1.9 kJ mol^(-1)) than that of toluene oxidation. Significantly, the transformation of benzyl alcohol indeed contributed to the generation of benzaldehyde and this step conformed to a first-order parallel-consecutive model. Increased reaction temperature and residence time favored the transformation of benzyl alcohol to benzaldehyde. In addition, doping with molybdenum at Mn/Mo = 3/1 enhanced the catalytic performance of the heterogeneous catalyst and was attributed to the presence of a synergetic effect between different metal cations. Regarding the microscopic kinetics, the LH-OS-ND mechanism(Langmuir–Hinshelwood adsorption of reagents on the same type of active sites and non-dissociative adsorption of oxygen) was verified as responsible for the heterogeneous oxidation of toluene. Oxygen and benzaldehyde were weakly adsorbed(Δ H_(ads,Oxy) ≈^(-1)5 kJ mol^(-1), Δ H _(ads)0,Bald) ≈-30 kJ mol^(-1)), but showed strong mobility(Δ S_(ads,Oxy) ≈-22 J mol^(-1) K^(-1)), Δ S_(ads,Bald) ≈-39 J mol^(-1) K^(-1)). The fundamental intrinsic rates were deduced based on the LH-OS-ND mechanism and showed great consistency with the macroscopic results.

关键词： Liquid phase Oxidation of toluene Heterogeneous catalyst Benzaldehyde Kinetics LH-OS-ND mechanism

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Error Analysis of A New Higher Order Boundary Element Method for A Uniform Flow Passing Cylinders

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China Ocean Engineering 2023年第3期37卷 369-377页

作者： SUN Shi-yan CUI jie BAO Chao-ming School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

A higher order boundary element method(HOBEM)is presented for inviscid flow passing cylinders in bounded or unbounded *** traditional boundary integral equation is established with respect to the velocity potential and its normal *** present work,a new integral equation is derived for the tangential *** boundary is discretized into higher order elements to ensure the continuity of slope at the element *** velocity potential is also expanded with higher order shape functions,in which the unknown coefficients involve the tangential *** expansion then ensures the continuities of the velocity and the slope of the boundary at element *** extensive comparison of the results for the analytical solution of cylinders,it is shown that the present HOBEM is much more accurate than the conventional BEM.

关键词： higher order boundary element method(HOBEM) error analysis integral equations for potential and velocity cylinders

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离心力场下多孔介质的不同孔隙率对热驱动换热影响的研究

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航空动力学报 2006年第6期21卷 972-977页

作者：夏婕常海萍南京航空航天大学能源与动力学院南京210016

以涡轮叶片新型超级冷却技术的研究为背景,在具有冷却通道的新型冷却结构中加入多孔介质,采用实验与数值模拟相结合的方法研究了不同孔隙率条件下,新型冷却结构的热驱动换热规律,实验和计算结果基本一致。研究结果表明不同孔隙率条件下... 详细信息

以涡轮叶片新型超级冷却技术的研究为背景,在具有冷却通道的新型冷却结构中加入多孔介质,采用实验与数值模拟相结合的方法研究了不同孔隙率条件下,新型冷却结构的热驱动换热规律,实验和计算结果基本一致。研究结果表明不同孔隙率条件下,该新型冷却结构具有相同的换热规律:随着旋转速度、热流密度和冷气进口速度的增大,该结构的热驱动换热能力逐渐增强。同时实验研究发现,随着孔隙率的增大,热驱动换热效果降低。

关键词：航空、航天推进系统多孔介质孔隙率热驱动

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Evidence of temperature-controlled dissolved inorganic nitrogen distribution in a shallow lake

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Journal of Environmental Sciences 2022年第12期34卷 105-114页

作者： Yan Wen Wenqiang Zhang Baoqing Shan jie Qu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Dissolved inorganic nitrogen(DIN) plays an important role in aquatic ecosystems as an available source of nitrogen(N). Despite recent advances in our understanding of the effects of climate change on DIN in coastal waters, shallow high-latitude lakes exposed to large seasonal temperature differences have received limited research attention. Therefore,in the present study, Baiyangdian Lake(BYDL) was selected as the study area, as a typical high latitude shallow lake in North China. Based on water and sediment samples collected in spring, summer and winter seasons, DIN accumulation in sedimentary pore water and DIN diffusion fluxes at the sediment-water interface were quantified under different temperature conditions. Correlation analysis was used to establish the effects of temperature on DIN concentration and diffusion in different media. Results show that the diffusion of DIN at the lake sediment-water interface exhibited a strongly positive relationship with temperature, suggesting that high temperature conditions lead to greater DIN release from sediments. Cold temperatures cause DIN accumulation in sedimentary pore water, providing sufficient substrate for N-related bacteria in the sediment under cold temperature conditions. Temperature controls the vertical distribution of DIN by affecting its migratory diffusion and transformation at the sediment-water interface. These findings are valuable for understanding the impact of climate change on the distribution of N in inland shallow lakes,especially in high latitude shallow lakes subjected to large seasonal temperature differences throughout the year.

关键词： Shallow lake Temperature Dissolved inorganic nitrogen Vertical distribution Diffusion flux

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