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中国体外循环杂志 2024年第1期22卷 76-80页

作者：吕喆张义和赵荣延安大学医学院延安716000 空军军医大学第一附属医院心血管外科西安710032 延安大学附属医院心血管病中心

深低温停循环将体外循环与低温保护相结合是体外循环发展过程中的一项里程碑式技术。此技术应用于临床以来,已成为心脏大血管外科手术中必不可少的干预方式。因此,本文就其发展历史及其脑保护策略作一综述,为这一技术更好的应用于临床... 详细信息

深低温停循环将体外循环与低温保护相结合是体外循环发展过程中的一项里程碑式技术。此技术应用于临床以来,已成为心脏大血管外科手术中必不可少的干预方式。因此,本文就其发展历史及其脑保护策略作一综述,为这一技术更好的应用于临床和未来研究提供参考。

关键词：深低温停循环中低温停循环脑保护心脏大血管手术

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测量系统能力分析在剥离强度测试中的应用

电子质量 2024年第8期 8-12页

作者：韩笑薛微婷李易合中国电子科技集团公司第四十六研究所天津300220

覆铜板是电子产品的基础材料,在电路中起到组件互联的作用,其应用场合决定了覆铜板的铜箔与介质层之间必须具有良好的结合力,主要量化指标是剥离强度,剥离强度对覆铜板的质量有根本性的影响。然而,剥离强度测试是一个较为复杂的破坏性测... 详细信息

覆铜板是电子产品的基础材料,在电路中起到组件互联的作用,其应用场合决定了覆铜板的铜箔与介质层之间必须具有良好的结合力,主要量化指标是剥离强度,剥离强度对覆铜板的质量有根本性的影响。然而,剥离强度测试是一个较为复杂的破坏性测试,受铜箔厚度、介质层组分和微观界面等多种因素影响,并且破坏性测试过程本身难以通过标准样品对测量系统稳定性做出评测。因此,科学地开展测量系统能力分析在覆铜板剥离强度测试过程中非常重要。通过使用专业的数据软件分析量具测量能力Cg,根据各指标水平找出导致测量系统能力低下的原因,针对性开展测量系统的改进,以减少测试误差,提升测量结果的准确性,为覆铜板剥离强度测试的改进方向提供了良好的依据。

关键词：测量系统能力分析覆铜板剥离强度

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EFFECT OF MONTMORIllONITE ADDITION ON MECHANICAl CHARACTERIZATIONS OF POlYIMIDE NANOCOMPOSITE FIlMS

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Acta Mechanica Solida Sinica 2005年第3期18卷 200-206页

作者： Wang Xishu Zhang yihe Fu Shaoyun Feng Xiqiao Department of Engineering Mechanics FML Tsinghua University Beijing 100084 China Cryogenic Materials laboratory Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100080 China

Tensile deformation and fracture characteristics of polyimide/montmorillonite nanocomposite films are investigated to enhance the particular mechanical properties and understand the effective factors in dominating the mechanical properties of nanocomposites, such as the nanolayer, matrix and nanolayer/matrix interface. How to contribute to the mechanical properties of nanocomposite film is a very complex problem. In this paper, these factors are analyzed based on the addition amount and fracture mechanics. The results indicate that the specimen at 20 wt% MMT breaks prematurely with a fracture strength （σb = 78 MPa） much lower than that （σb = 128 MPa） at the 1 wt% MMT. However, the Young＇s modulus （3.2 GPa） of the former is higher than that （1.9 GPa） of the latter. Fractography also indicates that the brittle cracking formed in high content addition is the main cause of failure but microscopically ductile fracture morphology still exists locally. And for the trace element addition, the smaller threading slipping veins are evenly distributed on the entire fracture section of these films. Therefore, these characteristics would presumably be associated with both the concentration effects of size of nanocomposite sheets and the increasing deformation harmony in nanolayers.

关键词： nanocomposite film polyimide/montmorillonie fractography failure characterization SEM

Rational manipulation of composition and construction toward Zn/Co bimetal hybrids for electromagnetic wave absorption

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Journal of Materials Science & Technology 2023年第3期134卷 254-261页

作者： Xiuyun Ren yihe Song Zhenguo Gao Yalan Wu Zirui Jia Guanglei Wu Institute of Materials for Energy and Environment State Key Laboratory of Biofibers and Eco-TextilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an 710072China Department of Nephrology Xi’an People’s HospitalXi’an 710000China

Rational manipulation of multi-metal hybrids with controllable compositions and constructions is evolv-ing as an efficacious strategy for tunable electromagnetic(EM)characteristics and EM wave(EMW)***,a novel bi-orientation etching approach is proposed to regulate the chemical composi-tions and hybridization construction of Zn/Co hybrids,thence meeting the synergistic interaction among diverse compositions for ultra-high EMW *** to the stepwise heterometallic modi-fication by Zn in Co-ZIFs(Zn@Co-ZIF)and Co in Zn-ZIFs(Co@Zn-ZIF),corresponding pyrolysis products with variable Zn/Co atomic concentration and hybridization states(Zn@Co-C,Co@Zn-C)can be *** Co species was confirmed to have a positive impact on both the dielectric and magnetic response,while an appropriate amount of Zn hybridization in Co substance further enhanced the synergistic ef-fect between multiple loss mechanisms,promoting the minimum reflection loss and effective absorption bandwidth of Zn@Co-C reached-34.99 dB and 5.52 GHz(2.00 mm),***,this work re-veals the composition and construction dependency of bimetal hybrids on EMW absorption,which can be a strong reference for developing EMAs with diverse hybridization structures.

关键词： Hybridization Composition Construction Electromagnetic wave absorption

Phosphorus-doped Ni–Co sulfides connected by carbon nanotubes for flexible hybrid supercapacitor

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Frontiers of Chemical Science and Engineering 2023年第5期17卷 491-503页

作者： Shengwang Su li Sun Feng Xie Jialong Qian yihe Zhang Engineering Research Center of Ministry of Education for Geological Carbon Storage and low Carbon Utilization of Resources Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid WastesNational Laboratory of Mineral MaterialsSchool of Materials Science and TechnologyChina University of GeosciencesBeijing 100083China

As promising electrode materials for supercapacitors,nickel-cobalt bimetallic sulfides render the advantages of abundant redox reactions and inherently high ***,in general,unsatisfactory performance of low specific capacity,low rate capability,and fast capacity loss exist in Ni–Co sulfide ***,we rationally regulate phosphorus-doped nickel–cobalt sulfides(P-NCS)to enhance the electrochemical performance by gas–solid ***,carbon nanotubes(CNTs)as conductive additives are added to improve the cycle stability and conductivity and form the composite P-NCS/C/*** to density functional theory,more electrons near the Fermi surface of P-NCS are demonstrated notionally than those of simple *** results manifest that P-NCS/C/CNT exhibits superior electrochemical performance,e.g.,high specific capacity(932.0 C·g^(-1)at 1 A·g^(-1)),remarkable rate capability(capacity retention ratio of 69.1%at 20 A·g^(-1)),and lower charge transfer *** importantly,the flexible hybrid asymmetric supercapacitor is assembled using P-NCS/C/CNT and activated carbon,which renders an energy density of 34.875 W·h∙kg^(-1)at a power density of 375 W∙kg^(-1).These results show that as-prepared P-NCS/C/CNT demonstrates incredible possibility as a battery-type electrode for high-performance supercapacitors.

关键词： cobalt nickel sulfide phosphorus-doping hybrid supercapacitor carbon nanotube density functional theory

Recent advances in 2D semiconductor nanomaterials for photocatalytic CO_(2)reduction

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Nano Research 2023年第7期16卷 8542-8569页

作者： Tong li Hongwei Huang Shuobo Wang Yan Mi yihe Zhang Beijing Key laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes National Laboratory of Mineral MaterialsSchool of Materials Science and TechnologyChina University of Geosciences(Beijing)Beijing 100083China Goods and Material Department of CASIC Tertiary Research Institute China Aerospace Science and Industrial CorporationBeijing 100074China Key laboratory of Chemistry and Engineering of Forest Products State Ethnic Affairs CommissionGuangxi Key Laboratory of Chemistry and Engineering of Forest ProductsGuangxi Collaborative Innovation Center for Chemistry and Engineering of Forest ProductsGuangxi Minzu UniversityNanning 530006China

For decades,global warming and energy shortages have been two urgent problems in human *** solar-driven photocatalytic conversion of carbon dioxide(CO_(2))into hydrocarbon fuels is expected to become a technology to solve these ***-dimensional(2D)materials shine in the field of photocatalytic CO_(2)due to their layered structure,larger specific surface area,more active sites,and larger charge transfer *** article reviews the progress of CO_(2)reduction by several types of 2D materials in recent ***,the reduction of CO_(2)is difficult in terms of kinetics and thermodynamics,but it is found through theoretical calculations and experiments that 2D materials have certain advantages in the reduction of CO_(2).Then the preparation methods of 2D materials are summarized and a variety of 2D materials are discussed and ***,an outlook on the development trend of 2D materials is *** review aims to provide systematic and concise guidance for the design of 2D nanomaterials for photocatalytic CO_(2)reduction.

关键词： two-dimensional(2D)materials photocatalysis CO_(2)reduction charge separation reactive sites

BP神经网络算法在求解数学建模最优化问题中的应用

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计算机应用文摘 2024年第6期40卷 72-74,79页

作者：吴小兰张益敏张奕河福建电力职业技术学院福建泉州362000

为了解决目标函数较为复杂、无法用初等函数表示的最优化问题,文章采用了结合BP神经网络与遗传算法的方法进行求解。求解过程分为两个模块:第一,利用BP神经网络算法确定目标函数的解析式;第二,利用遗传算法寻找目标函数的最优解。为验... 详细信息

为了解决目标函数较为复杂、无法用初等函数表示的最优化问题,文章采用了结合BP神经网络与遗传算法的方法进行求解。求解过程分为两个模块:第一,利用BP神经网络算法确定目标函数的解析式;第二,利用遗传算法寻找目标函数的最优解。为验证该方法的可行性,文章对单变量和多变量两种情况进行了验证。

关键词： BP神经网络遗传算法最优化

A Novel Dual Pointer Approach for Entity Mention Extraction

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Chinese Journal of Electronics 2021年第1期30卷 127-133页

作者： lIU Jie PANG yihe ZHANG Kai lIU lizhen YU Zhengtao Department of Information Engineering Capital Normal University Research Center for language Intelligence Capital Normal University Department of Information Engineering and Automation Kunming University of Science and Technology

The named entity extraction task aims to extract entity mentions from the unstructured text,including names of people, places, institutions and so on. It plays an important role in many Natural language processing(NlP) tasks, such as knowledge bases construction, automatic question answering system and information extraction. Most of the existing entity extraction studies are based on the long text data, which are easier to annotate due to the sufficient contextual information. Extracting entities from short texts such as search queries, conversations is still a challenging *** paper proposes a dual pointer approach for entity mention extraction, it extracts one entities by two position pointers of the input sentence. The end-to-end deep neural networks model based on the proposed approach can extract the entities by serially generating the dual *** evaluation results on the Chinese public dataset show that the model achieves the state-of-the-art results over the baseline models.

关键词： Dual pointer approach Entity extraction Deep neural networks Natural language processing

Amorphous red phosphorus anchored on carbon nanotubes as high performance electrodes for lithium ion batteries

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Nano Research 2018年第5期11卷 2733-2745页

作者： li Sun Yu Zhang Deyang Zhang Jingang liu yihe Zhang Beijing Key laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes National Laboratory of Mineral Materials School of Materials Science and Technology China University of Geosciences Beijing 100083 China

Red phosphorus-carbon nanotube （P@CNT） composites were synthesized as anodes for advanced lithium ion batteries via a facile solution-based method at room temperature. In these composites, the entangled P@CNT nanostructure reduced the aggregation of both components and allowed their complete utilization in a synergetic manner. The highly conductive and porous CNT framework, along with the nanoscale red P particles intimately anchored on the CNT surface, conferred the composite with excellent ion/electron transport properties. Volume expansion within the red P particles was mitigated by their amorphous and nanoscale features, which can be well buffered by the soft CNTs, therefore maintaining an integrated electrode structure during cycling. When used as an anode in lithium ion batteries, the composite exhibited a reversible capacity of 960 mAh·g^-1 （based on the overall weight of the composite） after 120 cycles at 200 mA·g^-1. The composite also delivered excellent high-rate capability with capacities of 886, 847, and 784 mAh·g^-1 at current densities of 2,000, 4,000, and 10,000 mA·g^-1 respectively, which reveals its potential as a high performance anode for lithium ion batteries.

关键词： red phosphorus carbon nanotubes anode lithium ion battery

Joule–Thomson expansion of RN-AdS black hole immersed in perfect fluid dark matter

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Communications in Theoretical Physics 2021年第9期73卷 105-112页

作者： yihe Cao Hanwen Feng Wei Hong Jun Tao Center for Theoretical Physics College of PhysicsSichuan UniversityChengdu610065China

In this paper,we study the Joule–Thomson expansion for RN-AdS black holes immersed in perfect fluid dark *** perfect fluid dark matter is one of the dark matter candidates,we are interested in how it influences the thermodynamic properties of black ***,the negative cosmological constant could be interpreted as thermodynamic pressure and its conjugate quantity as the thermodynamic volume,which give us more physical insights into the black ***,we derive the thermodynamic definitions and study the critical behaviour of the black ***,the explicit expression of Joule–Thomson coefficient is obtained from the basic formulas of the pressure,the volume,the entropy and the ***,we obtain the inversion curves in terms of charge Q and parameterλ.Furthermore,we analyse the isenthalpic curve in T–P graph with the cooling–heating region determined by the inversion *** last,we derive the ratio of minimum inversion temperature to critical temperature and compare the result with that in the RN-AdS case.

关键词： Joule-Thomson expansion black hole perfect fluid dark matter