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Microstructure evolution and reaction behavior of Cu–Ni alloy and B4C powder system

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Progress in Natural Science:Materials International 2021年第1期31卷 55-62页

作者： Lei Jia ming-fang yang Zhen-lin Lu Jin Xu Hui Xie Katsuyoshi Kondoh School of Materials Science and Engineering Xi'an University of Technology School of Materials Engineering Xi'an Aeronautical University Joining and Welding Research Institute Osaka University

Microstructure evolution and reaction behavior of Cu–Ni alloy and B4C power system was studied by in-situ and static experimental investigations along with theoretical calculations. The reaction process was as follows. Firstly,B4C decomposed into B and C atoms, and then B atoms diffused into Cu–Ni matrix, leading to the formation of Ni2B particles. Subsequently, Ni atoms diffused into B4C, forming a loose mixture of Ni2B and amorphous C at the initial powder boundary. Finally, with the completion of reaction, Ni2B particles at the powder boundary grew into a monolithic block, and then C substance was excluded out and accumulated at the edge of this monolithic Ni2B block. It is believed that the formation of Ni2B phase is caused by the most negative change of Gibbs free energy among all the potential reactions between Ni–B and Ni–B4C systems.

关键词： Metal-matrix composites Reaction behavior Microstructure evolution Cu–Ni/B4C composite In-situ experiment

Fetal reduction by bipolar cord coagulation in managing complicated monochorionic multiple pregnancies： preliminary experience in China

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Chinese Medical Journal 2010年第5期123卷 549-554页

作者： HE Zhi-ming fang Qun yang Yong-zhong LUO Yan-min CHEN Jun-hong CHEN Yong-zhen ZHOU Yi CHEN Min-ling Fetal Medicine Center First Affiliated Hospital of Sun Yat-sen University Guangzhou Guangdong 510080 China

Background Monochorionic multiple pregnancies （MMPs） are associated with higher rates of perinatal morbidity and mortality caused by interfetal vascular anastomoses in the monochorionic placenta, which can lead to fetal health interactions. In some circumstances, selective feticide of the affected fetus is necessary to save the healthy co-twin. We evaluated the effects and safety of our initial experiences using bipolar cord coagulation for the management of complicated MMPs. Methods Using ultrasound-guided bipolar cord coagulation, we performed selective feticide on 14 complicated MMPs （5 with twin-twin transfusion syndrome, 4 with acardia, 3 with discordant structural anomalies, and 2 with severe selective intrauterine growth restriction）. One patient with monochorionic triplets received the procedure twice to terminate 2 affected fetuses for different JndJcatJons. Data regarding the operations, complications and neonatal outcomes were analyzed. Results Cord occlusions were successfully performed in 13/14 （93%） cases. The failure happened in an acardiac fetus and the pregnancy was terminated by induction. The included cases delivered at a mean gestational age of 35.4 weeks with a perinatal survival rate of 11/13 （85%）. Three operation-related complications occurred （21%）, including membrane rupture of the terminated sac （1 case）, preterm labor at 28 weeks gestation （1 case）, and chorioamniotic membrane separation （1 case）. Amnioinfusion was indicated in 11 procedures to expand the target sacs for entering the trocar and obtaining sufficient working space. However, in all 4 cases of acardia, the acardiac sacs showed extreme oligohydramnios and could not be well expanded by infusion; thus, the trocar had to be inserted from the sac of the preserved co-twin. Conclusions The application of bipolar cord coagulation in complicated MMPs is safe and improves the prognosis. Amnioinfusion is useful in helping to expand the target sac when the working space is limited.

关键词： pregnancy reduction, multifetal," monochorionic cord coagulation," twin-twin transfusion syndrome," acardia

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被动式建筑发展现状及策略

价值工程 2021年第27期40卷 194-196页

作者：方明扬湖北工业大学武汉430068

近年来人工耗能带来的城市气候问题和能源问题,开始影响着人们的生活和社会的发展。为了推进被动式建筑在国内的发展,降低人工能耗,改善夏热冬冷地区能源问题和气候问题。文章阐释了被动式建筑的概念,叙述了被动式建筑在国内外发展现状... 详细信息

近年来人工耗能带来的城市气候问题和能源问题,开始影响着人们的生活和社会的发展。为了推进被动式建筑在国内的发展,降低人工能耗,改善夏热冬冷地区能源问题和气候问题。文章阐释了被动式建筑的概念,叙述了被动式建筑在国内外发展现状,选择了三个具体案例进行分析,提出被动式建筑的设计方法和策略。为被动式建筑的发展和普及提供参考。

关键词：被动式建筑低能耗建筑能源

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光子晶体中掺杂激活杂质的光增益研究

人工晶体学报 2006年第2期35卷 332-336,341页

作者：沈廷根吴炳坚方明阳盛勇方云团马俊峰焦蓬蓬江苏大学物理系镇江212003 江苏大学通信系镇江212013 镇江船艇学院基础系镇江212003

本文借助光子晶体中二能级原子的自发辐射理论说明缺陷态局域场存在的必然性以及局域场基本性质,为研究掺杂自发辐射的内在规律提供了理论依据,在此基础上,将自发辐射理论与数值模拟相结合,在缺陷介质中掺入和未掺入激活杂质时,数值模... 详细信息

本文借助光子晶体中二能级原子的自发辐射理论说明缺陷态局域场存在的必然性以及局域场基本性质,为研究掺杂自发辐射的内在规律提供了理论依据,在此基础上,将自发辐射理论与数值模拟相结合,在缺陷介质中掺入和未掺入激活杂质时,数值模拟研究一维光子晶体的掺杂局域场特征以及受激辐射增强和透射率大于1现象与光子带隙边缘群速度异常和掺杂层复有效折射率负的虚部之间的内在规律,由此说明如在光子晶体的缺陷介质中掺入激活杂质,复有效折射率具有负的虚部,光子禁带中会出现品质因子非常高的杂质态,具有很大的态密度,这样便可实现自发辐射的增强,出现较强的受激辐射放大,在带隙的边缘处,光子晶体的群速度较小或群速度异常,受激辐射放大最容易出现在靠近光子带隙的边缘。

关键词：光子晶体自发辐射激活杂质光增益

掺杂光子晶体光纤自发辐射与掺杂激活杂质的光增益透射谱研究

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量子光学学报 2006年第2期12卷 113-119页

作者：李正华沈廷根郑浩吴炳坚方明阳镇江船艇学院江苏大学物理系江苏镇江212013 江苏大学应用物理研究所

借助光子晶体中二能级原子的自发辐射理论证明缺陷态的局域场存在的必然性以及局域场基本性质,为研究光子晶体光纤掺杂自发辐射的内在规律提供了理论依据。且将自发辐射理论与数值模拟相结合,在缺陷介质中掺激活杂质时,研究了光子晶体... 详细信息

借助光子晶体中二能级原子的自发辐射理论证明缺陷态的局域场存在的必然性以及局域场基本性质,为研究光子晶体光纤掺杂自发辐射的内在规律提供了理论依据。且将自发辐射理论与数值模拟相结合,在缺陷介质中掺激活杂质时,研究了光子晶体光纤的掺杂局域场特征以及受激辐射增强和透射率大于1现象与光子带隙群速度异常和掺杂层复有效折射率成负的虚部之间的内在关系。由此说明光子晶体光纤的缺陷介质中掺入激活杂质时,光子禁带中能出现品质因子非常高的杂质态,具有很大的态密度,较强的受激辐射放大。

关键词：光子晶体光子晶体光纤自发辐射光子禁带激活杂质光增益

天然气输气管线清管通球计算机仿真系统的设计与实现

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天然气工业 1998年第3期18卷 69-72页

作者：李天太方明杨军全刘向东张振文单吉全西安石油学院长庆石油勘探局采气厂

由于天然气输气管线埋在地下，在通球清管过程中，球的运行情况不能直接观察，管线入口和出口压力在球运行过程中的变化也不能提前预测，也难准确控制进气量，使球能以１ｍ／ｓ的速度到达出口，为此进行了天然气输气管线清管通球计算机... 详细信息

由于天然气输气管线埋在地下，在通球清管过程中，球的运行情况不能直接观察，管线入口和出口压力在球运行过程中的变化也不能提前预测，也难准确控制进气量，使球能以１ｍ／ｓ的速度到达出口，为此进行了天然气输气管线清管通球计算机仿真系统的设计与实现的研制。该仿真系统是在深入分析和研究天然气输气管线清管通球运行规律的影响因素的基础上，以数据库管理、计算机仿真技术和人工智能等新技术为主要工具来开发的。着重介绍了该仿真系统的总体结构与功能设计，软件编程与调试。该仿真系统能真实仿真清管球在管线内运行，通过对靖边—榆林输气管线多次清管通球的运行过程实际模拟，其符合率在９３％以上。

关键词：天然气输气管道清管计算机仿真系统设计

Inter-Skeleton Conductive Routes Tuning Multifunctional Conductive Foam for Electromagnetic Interference Shielding, Sensing and Thermal Management

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NANO-MICRO LETTERS 2025年第1期17卷 1-18页

作者： Li, Xufeng Chen, Chunyan Li, Zhenyang Yi, Peng Zou, Haihan Deng, Gao fang, ming He, Junzhe Sun, Xin Yu, Ronghai Shui, Jianglan Pan, Caofeng Liu, Xiaofang Beihang Univ Sch Mat Sci & Engn Beijing 100191 Peoples R China Beihang Univ Inst Atom Mfg Beijing 100191 Peoples R China Tianmushan Lab Xixi Octagon City Hangzhou 310023 Peoples R China Beijing Inst Environm Features Sci & Technol Electromagnet Scattering Lab Beijing 100854 Peoples R China

Unique inter-skeleton conductive films are constructed in polymer *** resistance change of the foam can reach four orders of magnitude under *** foam exhibits strain-adaptive electromagnetic interference shielding performance, anti-interference pressure sensor with high sensitivity over a wide pressure range and compression-regulated Joule heating function. Conductive polymer foam (CPF) with excellent compressibility and variable resistance has promising applications in electromagnetic interference (EMI) shielding and other integrated functions for wearable electronics. However, its insufficient change amplitude of resistance with compressive strain generally leads to a degradation of shielding performance during deformation. Here, an innovative loading strategy of conductive materials on polymer foam is proposed to significantly increase the contact probability and contact area of conductive components under compression. Unique inter-skeleton conductive films are constructed by loading alginate-decorated magnetic liquid metal on the polymethacrylate films hanged between the foam skeleton (denoted as AMLM-PM foam). Traditional point contact between conductive skeletons under compression is upgraded to planar contact between conductive films. Therefore, the resistance change of AMLM-PM reaches four orders of magnitude under compression. Moreover, the inter-skeleton conductive films can improve the mechanical strength of foam, prevent the leakage of liquid metal and increase the scattering area of EM wave. AMLM-PM foam has strain-adaptive EMI shielding performance and shows compression-enhanced shielding effectiveness, solving the problem of traditional CPFs upon compression. The upgrade of resistance response also enables foam to achieve sensitive pressure sensing over a wide pressure range and compression-regulated Joule heating function.

关键词： Inter-skeleton conductive films Conductive polymer foam Liquid metal Electromagnetic interference shielding

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交通仿真的发展及研究现状

系统仿真学报 2003年第8期15卷 1179-1183页

作者：魏明杨方廷曹正清中国农业大学北京100083 北京仿真中心北京100854

交通仿真是智能交通运输系统(ITS)的一项重要内容,文章从交通仿真的研究意义和研究内容出发,介绍了交通仿真的三种模型,并重点介绍了其中的微观仿真模型,作者在文中描述了国内外交通仿真的发展历程和研究现状,并对其中的一些典型软件和... 详细信息

交通仿真是智能交通运输系统(ITS)的一项重要内容,文章从交通仿真的研究意义和研究内容出发,介绍了交通仿真的三种模型,并重点介绍了其中的微观仿真模型,作者在文中描述了国内外交通仿真的发展历程和研究现状,并对其中的一些典型软件和模型作了介绍,文章的最后还指出了当前交通仿真研究存在的一些不足之处。

关键词：交通仿真模型发展软件

A Whale Optimization Algorithm with Distributed Collaboration and Reverse Learning Ability

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Computers, Materials & Continua 2023年第6期75卷 5965-5986页

作者： Zhedong Xu Yongbo Su fang yang ming Zhang School of Architecture and Civil Engineering Anhui Polytechnic UniversityWuhu241000China

Due to the development of digital transformation,intelligent algorithms are getting more and more *** whale optimization algorithm(WOA)is one of swarm intelligence optimization algorithms and is widely used to solve practical engineering optimization ***,with the increased dimensions,higher requirements are put forward for algorithm *** double population whale optimization algorithm with distributed collaboration and reverse learning ability(DCRWOA)is proposed to solve the slow convergence speed and unstable search accuracy of the WOA algorithm in optimization *** the DCRWOA algorithm,the novel double population search strategy is ***,the reverse learning strategy is adopted in the population search process to help individuals quickly jump out of the non-ideal search *** experi-ments are carried out using standard test functions with different dimensions(10,50,100,200).The optimization case of shield construction parameters is also used to test the practical application performance of the proposed *** results show that the DCRWOA algorithm has higher optimization accuracy and stability,and the convergence speed is significantly ***,the proposed DCRWOA algorithm provides a better method for solving practical optimization problems.

关键词： Whale optimization algorithm double population cooperation distribution reverse learning convergence speed