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Chinese Journal of Polymer Science 2024年第3期42卷 352-363,I0008页

作者： Yuan Ji shi-Da Han Hong Wu Shao-Yun Guo Feng-Shun Zhang jian-Hui Qiu The State Key Laboratory of Polymer Materials Engineering Sichuan Provincial Engineering Laboratory of Plastic/Rubber Complex Processing TechnologyPolymer Research InstituteSichuan UniversityChengdu 610065China Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China Department of Mechanical Engineering Faculty of Systems Science and TechnologyAkita Prefectural UniversityAkita 015-0055Japan

Silicone rubber(SR) composites are most widely used as thermal interface materials(TIMs) for electronics heat dissipation. Thermal impedance as the main bottleneck limiting the performance of TIMs is usually neglected. Herein, the thermal impedance of SR composites loaded with different levels of hexagonal boron nitride(h-BN) as TIMs was elaborated for the first time by the ASTM D 5470 standard test and finite element analysis. It was found that elastic modulus and surface roughness of SR composites increased with the increase of h-BN content, indicating that the conformity was reduced. When the assembly pressure was 0.69 MPa, there existed an optimal h-BN content at which the contact resistance was minimum(0.39 K·cm^(2)·W^(-1)). Although the decreased bond line thickness(BLT) by increasing the assembly pressure was beneficial to reduce the thermal impedance, the proper assembly pressure should be selected to prevent the warpage of the contact surfaces and the increase in contact resistance, according to the compression properties of the SR composites. This study provides valuable insights into fabrication of high-performance TIMs for modern electronic device applications.

关键词： Thermal interface materials Hexagonal boron nitride Thermal impedance Surfaces

Mechanical properties of multi-scale germanium specimens from space solar cells under electron irradiation

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Chinese Journal of Aeronautics 2024年第1期37卷 173-185页

作者： jian QIU Maliya HEINI Jusha MA Wenjia HAN Xunchun WANG Jun YIN Yan shi Cunfa GAO State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Chemistry and Civil Engineering Shaoguan UniversityShaoguan 512005China Key Laboratory of Functional Materials and Devices for Special Environments of Chinese Academy of Sciences Chinese Academy of SciencesUrumqi 830011China Shanghai Institute of Space Power-Sources Shanghai 200245China

During long-term service in space,Gallium Arsenide(GaAs)solar cells are directly exposed to electron irradiation which usually causes a dramatic decrease in their *** the multilayer structure of solar cells,the germanium(Ge)layer occupies the majority of the thickness as the *** to the intrinsic brittleness of semiconductor material,there exist various defects during the preparation and assembly of solar cells,the influences of which tend to be intensified by the irradiation *** this work,first,Ge specimens for mechanical tests were prepared at scales from microscopic to ***,after different doses of electron irradiation,the mechanical properties of the Ge specimens were *** experimental results demonstrate that electron irradiation has an obvious effect on the mechanical property variation of Ge in diverse *** four-point bending test indicates that the elastic modulus,fracture strength,and maximum displacement of the Ge specimens all increase,and reach the maximum value at the irradiation dose of 1×10^(15)e/cm^(2).The micrometer scale cantilever and nanoindentation tests present similar trends for Ge specimens after *** Force Microscope(AFM)also observed the change in surface ***,a fitting model was established to characterize the relation between modulus change and electron irradiation dose.

关键词： Electron irradiation Germanium Mechanical properties Multi-scale Space solar cells

Hongjin Xiaojie Capsule, a Chinese patent medicine, for treating moderate to severe cyclical breast pain: A single-blind randomized controlled trial

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Journal of Integrative Medicine 2024年第5期22卷 552-560页

作者： Qiong Zhang Ying-yi Fan Xue-qing Wu Yan-dan Huo Chun-hui Wang shi-bing Liang Ting Wang Rong Zhong Xuan Wang Bao-yong Lai Xiao-hua pei jian-ping Liu Graduate School Beijing University of Chinese Medicine Department of Breast Beijing University of Chinese Medicine Third Affiliated Hospital Department of Breast Shuguang HospitalShanghai University of Traditional Chinese Medicine Department of Breast Sichuan Second Hospital of Traditional Chinese Medicine Department of Breast Xiamen HospitalBeijing University of Chinese Medicine Center for Evidence-Based Chinese Medicine Beijing University of Chinese Medicine

Background: Moderate to severe breast pain has major effects on the quality of life for patients. Patent Chinese medicines are widely used in the treatment of breast pain due to their stable dosage form and good ***: To evaluate the beneficial effects and safety of Hongjin Xiaojie Capsule(HJXJC), a Chinese patent medicine, for the treatment of cyclical breast ***, setting, participants and intervention: This is a multicenter, single-blind randomized controlled trial conducted in 3 medical centers in China from 2019 to 2021. Patients with moderate to severe cyclic breast pain were randomly divided into the intervention group(who took HJXJC, four capsules per dose,three times a day for 12 weeks) and the control group(waiting for the treatment) in a 1:1 *** outcome measures: The primary outcome was pain duration, and the patients recorded measurements at baseline and at the end of weeks 4, 8, 12 and 16 on a patient log ***: The full analysis set(FAS) population included 298 participants(intervention group, n = 150;control group, n = 148), while the per-protocol analysis set(PPS) included 274 participants. After12 weeks, the duration of breast pain was significantly shorter in the intervention group(FAS: mean difference, –6.69; 95% CI, –7.58 to –5.80; P < 0.01, vs control. PPS: mean difference, –7.09; 95% CI, –8.01 to –6.16; P < 0.01, vs control). The Short-form McGill Pain Questionnaire(SF-MPQ) scores were significantly lower in the intervention group(FAS: mean difference, –12.55; 95% CI, –13.90 to –11.21; P < 0.01, vs control. PPS: mean difference, –13.07; 95% CI, –14.48 to –11.66; P < 0.01, vs control). The above indicators continued to be significantly different through week 16. Moreover, in the intervention group, breast lumps shrank after 12 weeks and the size of breast lumps was statistically smaller than that in the control group(P < 0.05), whereas the sizes of breast nodules and uterine fibroid showed no statistically sign

关键词： Hongjin Xiaojie Capsule Cyclical breast pain Randomized controlled trial Traditional Chinese medicine

Vibration Suppression for Active Magnetic Bearings Using Adaptive Filter with Iterative Search Algorithm

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 61-71页

作者： Jin-Hui Ye Dan shi Yue-Sheng Qi Jin-Hui Gao jian-Xin Shen IEEE Department of Electrical Engineering Zhejiang UniversityHangzhou 310027China CES and IEEE

Active Magnetic Bearing(AMB) is a kind of electromagnetic support that makes the rotor movement frictionless and can suppress rotor vibration by controlling the magnetic force. The most common approach to restrain the rotor vibration in AMBs is to adopt a notch filter or adaptive filter in the AMB controller. However, these methods cannot obtain the precise amplitude and phase of the compensation current. Thus, they are not so effective in terms of suppressing the vibrations of the fundamental and other harmonic orders over the whole speed range. To improve the vibration suppression performance of AMBs,an adaptive filter based on Least Mean Square(LMS) is applied to extract the vibration signals from the rotor displacement signal. An Iterative Search Algorithm(ISA) is proposed in this paper to obtain the corresponding relationship between the compensation current and vibration signals. The ISA is responsible for searching the compensating amplitude and shifting phase online for the LMS filter, enabling the AMB controller to generate the corresponding compensation force for vibration suppression. The results of ISA are recorded to suppress vibration using the Look-Up Table(LUT) in variable speed range. Comprehensive simulations and experimental validations are carried out in fixed and variable speed range, and the results demonstrate that by employing the ISA, vibrations of the fundamental and other harmonic orders are suppressed effectively.

关键词： Active Magnetic Bearing(AMB) Adaptive filter Iterative search algorithm Least mean square(LMS) Vibration suppression

Health Risk Assessment of Employees Exposed to Chlorination By-products of Recreational Water in Large Amusement Parks in Shanghai

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Biomedical and Environmental Sciences 2024年第8期37卷 865-875页

作者： Weizhao Cao Yiming Zheng Wenxuan Zhao Lisha shi Yunhui Zhang Lijun Zhang jian Chen Key Lab of Health Technology Assessment National Health Commission of the People’s Republic of China(Fudan University)Shanghai 200032China Key Laboratory of Public Health Safety Ministry of EducationSchool of Public HealthFudan UniversityShanghai 200032China Division of Public Health Service and Safety Assessment Shanghai Municipal Center for Disease Control and PreventionShanghai 200336China Shanghai Institute of Preventive Medicine Shanghai 200336China

Objective Chlorination is often used to disinfect recreational water in large amusement parks;however,the health hazards of chlorination disinfection by-products(DBPs)to occupational populations are *** study aimed to assess the exposure status of chlorinated DBPs in recreational water and the health risks to employees of large amusement *** Exposure parameters of employees of three large amusement parks in Shanghai were investigated using a *** typical chlorinated DBPs in recreational water and spray samples were quantified by gas chromatography,and the health risks to amusement park employees exposed to chlorinated DBPs were evaluated according to the WHO's risk assessment *** Trichloroacetic acid,dibromochloromethane,bromodichloromethane,and dichloroacetic acid were detected predominantly in recreational *** carcinogenic and non-carcinogenic risks of the five DBPs did not exceed the risk *** addition,the carcinogenic and non-carcinogenic risks of mixed exposure to DBPs were within the acceptable risk *** Typical DBPs were widely detected in recreational water collected from three large amusement parks in Shanghai;however,the health risks of DBPs and their mixtures were within acceptable limits.

关键词： Risk assessment Water Environmental health Occupational exposure Chlorinated disinfection by-product

Covalency competition induced selective bond breakage and surface reconstruction in manganese cobaltite towards enhanced electrochemical charge storage

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Green Energy & Environment 2024年第5期9卷 909-918页

作者： Peng Gao pei Tang Ying Mo peitao Xiao Wang Zhou shi Chen Hongliang Dong Ziwei Li Chaohe Xu Jilei Liu College of Materials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology for Clean EnergyHunan Province Key Laboratory for Advanced Carbon Materials and Applied TechnologyHunan UniversityChangshaHunan410082China Department of Materials Science and Engineering National University of Defense TechnologyChangshaHunan410073China Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials EngineeringUniversity of MacaoAvenida da UniversidadeTaipaMacao999078China Center for High Pressure Science and Technology Advanced Research PudongShanghai201203China College of Aerospace Engineering Chongqing UniversityChongqing400044China

Manganese cobaltite(MnCo_(2)_(4))is a promising electrode material because of its attractive redox chemistry and excellent charge storage *** previous work demonstrated that the octahedrally-coordinated Mn are prone to react with the hydroxyl ions in alkaline electrolyte upon electrochemical cycling and separates on the surface of spinel to reconstruct into d-MnO_(2) nanosheets irreversibly,thus results in a change of the reaction mechanism with Kþion ***,the low capacity has greatly limited its practical ***,we found that the tetrahedrally-coordinated Co_(2) þions were leached when MnCo_(2)_(4) was equilibrated in 1 mol L^(-1) HCl solution,leading to the formation of layered CoOOH on MnCo_(2)_(4) surface which is originated from the covalency competition induced selective breakage of the CoT–O bond in CoT–O–CoO and subsequent rearrangement of free Co_(6) *** as-formed CoOOH is stable upon cycling in alkaline electrolyte,exhibits conversion reaction mechanism with facile proton diffusion and is free of massive structural evolution,thus enables utilization of the bulk electrode material and realizes enhanced speciﬁc capacity as well as facilitated charge transfer and ion *** general,our work not only offers a feasible approach to deliberate modiﬁcation of MnCo_(2)_(4)'s surface structure,but also provides an in-depth understanding of its charge storage mechanism,which enables rational design of the spinel oxides with promising charge storage properties.

关键词： Manganese cobaltite Tetrahedrally-coordinated Co^(2+)leaching Selective bond breakage Surface reconstruction Charge storage mechanisms

An introductory review on the common brown leafhopper(Orosius orientalis):A new soybean pest

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Oil Crop Science 2024年第3期9卷 198-203页

作者： Tianhao pei Xin Cui Shusen shi Yu Gao College of Plant Protection Jilin Agricultural UniversityChangchun130118PR China Key Laboratory of Soybean Disease and Pest Control Ministry of Agriculture and Rural AffairsChangchun130118PR China

Soybean pests are one of the major factors limiting yield *** the expansion of area and changes in cropping patterns,a number of new pests have been identified in the main soybean production areas of *** common brown leafhopper,Orosius orientalis,is a new pest associated with soybean stay-green virus that has been discovered on cultivated soybean crop in the Yellow-Huai-hai region of China in recent *** polyphagous insect has a wide feeding range and infests a variety of important grain and cash *** paper presents the basic information,geographical distribution,hosts,damage characteristics,plant virus transmission,occurrence patterns,and prevention and control measures *** review also provides insights into integrated prevention and control of the genus Orosius as an insect vector.

关键词： Soybean Leafhopper Plant virus Insect vector Orosius orientalis

How variable progenitor clones construct a largely invariant neocortex

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National Science Review 2024年第1期11卷 129-144页

作者： Zhongfu Shen Jiajun Yang Qiangqiang Zhang Kuiyu Wang Xiaohui Lv Xiaolin Hu jian Ma Song-Hai shi New Cornerstone Science Laboratory IDG/McG overn Institute for Brain Research Tsinghua-Peking Center for Life Sciences Beijing Frontier Research Center for Biological Structure School of Life Sciences Tsinghua University Department of Computer Sciences Tsinghua University College of Life Sciences Nankai University Chinese Institute for Brain Research

The neocortex contains a vast collection of diverse neurons organized into distinct layers. While nearly all neocortical neurons are generated by radial glial progenitors(RGPs), it remains largely unclear how a complex yet organized neocortex is constructed reliably and robustly. Here, we show that the division behavior and neuronal output of RGPs are highly constrained with patterned variabilities to support the reliable and robust construction of the mouse neocortex. The neurogenic process of RGPs can be well-approximated by a consistent Poisson-like process unfolding over time, producing deep to superficial layer neurons progressively. The exact neuronal outputs regarding layer occupation are variable; yet, this variability is constrained systematically to support all layer formation, largely reflecting the variable intermediate progenitor generation and RGP neurogenic entry and exit timing differences. Together, these results define the fundamental features of neocortical neurogenesis with a balanced reliability and variability for the construction of the complex neocortex.

关键词： neocortex radial glial progenitor intermediate progenitor neurogenesis clonal variability layer formation

High-efficiency sodium storage of Co_(0.85)Se/WSe_(2) encapsulated in N-doped carbon polyhedron via vacancy and heterojunction engineering

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Carbon Energy 2024年第1期6卷 94-107页

作者： Ya Ru pei Hong Yu Zhou Ming Zhao jian Chen Li Xin Ge Wei Zhang Chun Cheng Yang Qing jiang Key Laboratory of Automobile Materials(Jilin University) Ministry of EducationSchool of Materials Science and EngineeringJilin UniversityChangchunChina Jilin Provincial International Cooperation Key Laboratory of High-Efficiency Clean Energy Materials Electron Microscopy CenterJilin UniversityChangchunChina

With the advantage of fast charge transfer,heterojunction engineering is identified as a viable method to reinforce the anodes'sodium storage ***,vacancies can effectively strengthen the Na+adsorption ability and provide extra active sites for Na+***,their synchronous engineering is rarely ***,a hybrid of Co_(0.85)Se/WSe_(2) heterostructure with Se vacancies and N-doped carbon polyhedron(CoWSe/NCP)has been fabricated for the first time via a hydrothermal and subsequent selenization *** aberration-corrected transmission electron microscopy confirms the phase interface of the Co_(0.85)Se/WSe_(2) heterostructure and the existence of Se *** functional theory simulations reveal the accelerated charge transfer and enhanced Na+adsorption ability,which are contributed by the Co_(0.85)Se/WSe_(2) heterostructure and Se vacancies,*** expected,the CoWSe/NCP anode in sodium-ion battery achieves outstanding rate capability(339.6 mAh g^(−1) at 20 A g^(−1)),outperforming almost all Co/W-based selenides.

关键词： Co_(0.85)Se/WSe_(2)heterostructure density functional theory simulations N-doped carbon polyhedron Se vacancies sodium-ion batteries

Annulation Cascades of Cyclosulfonium Salts and Alkenes towards Sulfur-Containing N-Heterocycles by Visible Light/Copper Catalysis

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Chinese Journal of Chemistry 2024年第14期42卷 1637-1643页

作者： Jie Ma Xufeng Li Yuqing Chen Yongjia shi Xiuyan Song jian Lv Daoshan Yang Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science MOECollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdaoShandong266042 China Zhejiang Wansheng Co. Ltd.LinhaiZhejiang317000 China National Engineering Research Center of Low-Carbon Processing and Utilization of Forest Biomass Nanjing Forestry UniversityNanjingJiangsu210037 China

Although,great achievements have been made in the synthesis of heterocycles using radical addition/cyclization strategy,developing versatile alkyl radical precursors,especially the non-stabilized long chain alkyl radicals for this strategy still remains a huge ***,we report an efficient annulation cascade reaction between cyclosulfonium salts and alkenes for the synthesis of sulfur-containing N-heterocycles by visible light/copper catalysis under mild *** C—S bond cleavage/radical cascade reaction delivers a variety of corresponding N-heterocycles containing aryl alkyl thioether motifs with good functional group ***,the current system could be used for the late-stage functionalization of complex bioactive molecules.

关键词： Visible light Radical reactions C-C coupling Sulfur heterocycles Photoredox catalysis