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Green Energy & Environment 2025年第1期10卷 161-172页

作者： Meng-Ying Liu Zhe-Hui Zhang Xue-Qi Wang Qian Sun Chen Zhang Yu Li Zhuohua Sun Katalin Barta Feng peng Tong-Qi Yuan State Key Laboratory of Efficient Production of Forest Resources Beijing Forestry UniversityBeijing100083China Beijing Key Laboratory of Lignocellulosic Chemistry Beijing Forestry UniversityBeijing100083China Department of Chemistry Organic and Bioorganic ChemistryUniversity of GrazHeinrichstrasse 28/II8010 GrazAustria

Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent ***,taking advantage of the“lignin first”strategy,corn straw is converted to valuable chemicals including lignin monomers,furfural and 5-methoxymethylfurfural via a two steps *** key of this research lies in the development of a green and low-cost catalytic process utilizing magnetic Raney Ni catalyst and high boiling point ethylene *** utilization of neat ethylene glycol as the sole slovent under atmospheric conditions obviates the need for additional additives,thereby facilitating the entire process to be conducted in glass flasks and rendering it highly convenient for scaling *** the initial step,depolymerization of corn straw lignin resulted in a monomer yield of 18.1 wt%.Subsequently,in a dimethyl carbonate system,the carbohydrate component underwent complete conversion in a one-pot process,yielding furfural and 5-methoxymethylfurfural as the primary products with an impressive yield of 47.7%.

关键词： Atmospheric reductive catalytic fractionation Corn straw Ethylene glycol Raney Ni 5-Methoxymethylfurfural

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北京市免费避孕药具现代化服务模式探索研究

中国计划生育学杂志 2012年第7期20卷 442-445页

作者：王媛媛李兵辛晓娜彭左旗梅红光刘克军马旭北京协和医学院研究生院 100730 国家人口计生委科学技术研究所北京市计划生育药具管理站卫生部卫生发展研究中心

目的:探讨北京市免费避孕药具发放传统模式与现代化新模式的特点,为政府决策提供建议。方法:利用分层抽样法,抽取北京市6个区作为研究地区,通过小组访谈和现场调查等方法,对各区免费药具发放方式进行调查。结果:现代化免费药具发放新模... 详细信息

目的:探讨北京市免费避孕药具发放传统模式与现代化新模式的特点,为政府决策提供建议。方法:利用分层抽样法,抽取北京市6个区作为研究地区,通过小组访谈和现场调查等方法,对各区免费药具发放方式进行调查。结果:现代化免费药具发放新模式比传统模式覆盖人群更广,满足群众个性化需要,降低了基层药具发放工作压力,实现了药具发放领域的寓管理于服务之中的模式转变。结论:现代化的药具发放新模式利用现代化手段,更符合城市人口发展特征,使药具管理更具有科学性。

关键词：避孕药具发放模式现代服务

Microspheres trigged-stress concentration regulating piezoelectric properties of PVDF/elastomer composites

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Science China Chemistry 2025年

作者： Wenxian Zhang Jiahong Yang Qijun Sun Lu peng Tong Lin Shouke Yan Xiaoli Sun State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences State Key Laboratory of Separation Membranes and Membrane Processes School of Textile Science and EngineeringTiangong University Key Laboratory of Rubber-Plastics of Ministry of Education Shandong Provincial Key Laboratory of Rubber-PlasticsQingdao University of Science & Technology

Wearable self-powered piezoelectric pressure sensors are attracting tremendous ***,fabricating a high-sensitive elastic piezoelectric sensor for a broad response range remains ***,we assemble polar poly（vinylidene fluoride）(PVDF) microsphere-elastomer composites,achieving high-sensitive and wide-responsive pressure *** polar PVDF microspheres are produced cost-effectively through phase separation,enabling *** piezoelectric composite （PC） film demonstrates low Young’s modulus,and excellent anti-fatigue ***,the PC-based piezoelectric sensor exhibits a rather high sensitivity of 540 mV N-1in a wide sensing range （5–40 N）,240 times greater than the PVDF film-based sensor and comparable to the inorganic piezoelectric *** excellent performance is attributed to the highest average stress concentration on the spherical PVDF coupled with the remarkable deformation of dipoles of spherical PVDF in the flexible *** on excellent performance,this piezoelectric sensor achieves precise recognition of motions and sound *** high-sensitive flexible piezoelectric sensor enabling large area production with ultralow price exerts great potential in smart monitoring and intelligent robots.

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Multiphysics simulation and optimization of the in-situ beneficiation process of ilmenite minerals from lunar regolith

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Science China Earth Sciences 2025年第1期68卷 195-207页

作者： peng ZHANG Xin LIU Guanghui LIU Wei DAI Hanzhe YANG Haibo ZHENG Zhi WANG Ran NIU Yifan BAI Yang ZHANG Chengbao LIU Ge YANG Junwei YANG Guang ZHANG Technology and Engineering Center for Space Utilization Chinese Academy of Sciences Beijing Hegong Simulation Co. Ltd

The exploration and utilization of lunar resources have become the major objectives of future lunar exploration missions. The classified collection and processing of lunar minerals is the basic prerequisite for the in-situ exploration and utilization of lunar resources. In this study, we propose a scheme for in-situ separation of magnetic minerals from lunar soils using the dry magnetic separation method. The scheme can realize the purpose of separating magnetic minerals from lunar regolith by altering the motion trajectory of lunar regolith particles with different magnetic properties. Detailed modeling of the dry magnetic separation device is conducted, and the three-dimensional distribution of magnetic parameters is calculated and analyzed. Based on the characterization and analysis of the Chang E-5's samples, the morphologies and physical parameters of lunar regolith particles are modeled and simulated. A discrete element simulation of the motion process of lunar regolith particles under multi-physical field conditions is performed, and the influences of key parameters on the beneficiation performance of lunar magnetic minerals are investigated. Our results indicate that optimal separation and beneficiation of lunar regolith particles can be achieved under specific conditions of magnetic field strength and drum speed. Additionally, we analyze the effects of lunar weak gravity conditions and the charged nature of lunar particles on the beneficiation process, showing that these factors can obviously enhance the beneficiation process of lunar ilmenites. This study demonstrates the feasibility of using the dry magnetic separation method for the beneficiation of magnetic minerals from lunar regolith, providing a theoretical basis for the scientific tasks of collecting, processing, and utilizing lunar mineral resources.

关键词： Lunar regolith In-situ resource utilization Magnetic separation Classified sampling

全国计划生育技术服务信息化平台的设计与应用

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中国计划生育学杂志 2017年第8期25卷 514-518页

作者：赵君代巧云张宏光吴尚纯彭左旗唐文斌张序马旭国家卫生计生委科学技术研究所北京100081 北京协和医学院研究生院

目的:搭建全国计划生育技术服务信息化平台,加强计划生育技术服务档案的规范化管理。方法:制定计划生育技术服务档案和相关医疗文书的信息化流程和数据规范,采用企业级应用体系技术架构研发由表现层、业务逻辑层、数据访问层和基础设备... 详细信息

目的:搭建全国计划生育技术服务信息化平台,加强计划生育技术服务档案的规范化管理。方法:制定计划生育技术服务档案和相关医疗文书的信息化流程和数据规范,采用企业级应用体系技术架构研发由表现层、业务逻辑层、数据访问层和基础设备层构成的全国计划生育技术服务信息化平台,并进行应用示范。结果:搭建了由主体业务、随访管理、统计管理、专家智能、咨询交流五大系统组成的计划生育技术服务信息化平台,在各级妇幼保健计划生育服务和管理机构建立了通用的计划生育技术服务档案架构和应用。结论:全国计划生育技术服务信息化平台在示范应用中,实现了计划生育技术服务数据资料和档案管理流程的信息化,提高了基层服务机构的工作效率和服务质量,为促进计划生育技术服务转变和服务模式优化提供了技术支撑。

关键词：计划生育技术服务信息平台设计应用示范

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3期17卷 19-36页

作者： Xufeng Li Chunyan Chen Zhenyang Li peng Yi Haihan Zou Gao Deng Ming Fang Junzhe He Xin Sun Ronghai Yu Jianglan Shui Caofeng Pan Xiaofang Liu School of Materials Science and Engineering Beihang UniversityBeijing 100191People’s Republic of China Institute of Atomic Manufacturing Beihang UniversityBeijing 100191People’s Republic of China Tianmushan Laboratory Xixi Octagon CityYuhang DistrictHangzhou 310023People’s Republic of China Science and Technology On Electromagnetic Scattering Laboratory Beijing Institute of Environmental FeaturesBeijing 100854People’s Republic of China

Conductive polymer foam(CPF)with excellent compressibility and variable resistance has promising applications in electromagnetic interference(EMI)shielding and other integrated functions for wearable ***,its insufficient change amplitude of resistance with compressive strain generally leads to a degradation of shielding performance during ***,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 *** 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 ***,the resistance change of AMLM-PM reaches four orders of magnitude under ***,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 ***-PM foam has strain-adaptive EMI shielding performance and shows compression-enhanced shielding effectiveness,solving the problem of traditional CPFs upon *** 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

Mechanical properties and microstructures of Mg-6Si alloys fabricated using the tungsten-inert-gas arc additive manufacturing

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China Foundry 2025年

作者： peng-cheng Zhou Guo-qiang You Jin-yu Feng Lei Wang Xiao Lin Bin Jiang College of Materials Science and Engineering Chongqing University National Engineering Research Center for Magnesium Alloys Chongqing University National Key Laboratory of Advanced Casting Technologies Chongqing University

Si-containing Mg alloys solidified at conventional rates often contain coarse and sharp Mg2Si phases,which can result in inferior material *** this study,Mg-6wt.%Si （Mg-6Si） alloy was prepared by wire arc additive manufacturing （WAAM）,employing the gas tungsten arc welding technique with rapid *** microstructures and mechanical properties of the WAAM alloy were investigated and compared with those of the as-cast samples produced using a metal *** results indicate that the WAAM Mg-6Si is harder and stronger than the as-cast *** microhardness of the WAAM Mg-6Si increases by 36.6%in comparison to that of as-cast Mg-6Si ***,the average tensile strengths at room temperature and 150°C increases by 63.4%and 21.3%,*** refines both the Mg2Si phase and the overall grains,resulting in a homogeneous morphology and improved mechanical *** granular Mg2Si phase,characterized by fine particles with a diffused distribution,shows a significant increase in *** acicular Mg2Si phase is distributed along the grain boundaries,and its concentration significantly *** average grain size of the Mg2Si phase is about 9.20μm,about 5 times *** refinement and distribution of the granular Mg2Si phase,as well as the reduction in the amount of needle-like Mg2Si particles,are the key factors for improving the mechanical properties of WAAM Mg-6Si alloy.

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四川省2004年-2015年65952例病残儿医学鉴定疾病构成与顺位分析

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中国计划生育学杂志 2017年第11期25卷 744-750页

作者：赵君张宏光田爱平代巧云杨莉彭左旗袁燕李霞杨雪莹马旭国家卫生计生委科学技术研究所北京100081 成都中医药大学四川省人口和计划生育科学技术研究所四川省卫生和计划生育委员会四川大学华西第二医院

目的:对病残儿医学鉴定资料进行疾病构成及顺位分析,为制定重点防治策略提供依据。方法:基于标准化的国际疾病分类(ICD-10)编码自动归类流程,对四川省2004年—2015年地市级医学鉴定的65 952例病残儿对应的76 726个鉴定诊断进行疾病编码... 详细信息

目的:对病残儿医学鉴定资料进行疾病构成及顺位分析,为制定重点防治策略提供依据。方法:基于标准化的国际疾病分类(ICD-10)编码自动归类流程,对四川省2004年—2015年地市级医学鉴定的65 952例病残儿对应的76 726个鉴定诊断进行疾病编码,应用SPSS统计软件对12年间病残儿鉴定审批情况、基本人口学特征、疾病分类和总体顺位进行分析。结果:四川省20个市(州)2004年-2015年平均病残儿鉴定审批率为74.11%,鉴定时年龄(8.82±4.16)岁,男性病残儿占56.77%,农村病残儿占73.34%,性别比农村(146.29)高于城镇(98.29)。病残儿鉴定诊断共计849种疾病,前4类分别为先天性畸形、变形和染色体异常,神经系统疾病,眼和附器疾病,精神和行为障碍,所占比例分别为24.84%、17.87%、11.01%、10.96%。其中先天性畸形、变形和染色体异常又以循环系统(30.56%)、肌肉骨骼系统(23.57%)和生殖器官(10.58%)先天性畸形居多。居前10位疾病分别为癫痫(10.32%)、未特指的精神发育迟缓(6.61%)、大脑性瘫痪(4.47%)、屈光和调节疾患(4.30%)、心脏的其他先天性畸形(3.86%)、视觉障碍(3.80%)、心间隔先天性畸形(2.70%)、其他听觉丧失(2.13%)、脑的其他先天性畸形(1.84%)、头部损伤后遗症(1.26%)。结论:四川省病残儿医学鉴定中先天性畸形、变形和染色体异常最为常见,其中癫痫、精神发育迟缓、脑瘫、屈光和调节疾患、心脏先天性畸形是高发病种,需要针对这些重点疾病制定切实有效的防治对策,建立病残儿家庭登记及后续服务体系,有效管控高危家庭生育风险,提高出生人口素质。

关键词：病残儿性别比 ICD-10 疾病构成顺位分析四川省

Mitigating methodology of hardware non-ideal characteristics for non-volatile memory based neural networks

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Science China(Information Sciences) 2025年

作者： Lixia HAN peng HUANG Yijiao WANG Zheng ZHOU Haozhang YANG Yiyang CHEN Xiaoyan LIU Jinfeng KANG School of Integrated Circuits Peking University Beijing Advanced Innovation Center for Integrated Circuits School of Integrated Circuit Science and Engineering Beihang University

Non-volatile memory-based computing-in-memory (nvCIM) paradigm has been extensively studied to boost the energy efficiency of neural network accelerators in edge ***,the degradation of inference accuracy induced by the non-ideal characteristics across circuits,arrays,and devices is becoming a crucial *** this work,we establish a hardware characteristic behavior model to analyze the impact of nvCIM non-ideal characteristics on neural network *** we propose a hardware aware training and weight mapping correction methods to mitigate inference accuracy *** simulation verification,about 95%inference accuracy degradation is recovered by adopting the proposed mitigation method for various non-ideal characteristics and various neural network *** feasibility of the proposed method is further proved in an experimental example with a flash-based LeNet recognition system.

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Lung-targeted polyzwitterionic lipid nanoparticles for effective treatment of lung inflammation

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Science China Chemistry 2025年

作者： Wen Zhang Jiaxin Li Nan Wang Muzi Li Chen peng Xinyue Zhang Guanghui Ouyang Yan Li Beijing Key Laboratory for Bioengineering and Sensing Technology School of Chemistry and Biological Engineering University of Science and Technology Beijing CAS Key Laboratory of Colloid Interface and Chemical Thermodynamics Institute of Chemistry Chinese Academy of Sciences

Lipid nanoparticles (LNPs) are non-viral nucleic acid delivery systems that show great potential in vaccine development and disease treatment. Although LNPs are particularly advantageous for in vivo delivery, the wide application of LNPs is impeded as their systemic delivery of nucleic acid drugs to extrahepatic tissues remains highly challenging. To address this issue, we developed lung-targeted polyzwitterionic LNPs with zwitterionic polymer poly(2-methyacryloyloxyethyl phosphorylcholine)(PMPC) modified 1,2-dimyristoyl-sn-glycerol lipid for the delivery of small interfering RNA (siRNA). Three libraries with 90PMPC-LNPs@siRNA were established. The polyzwitterionic PMPC-LNPs had high siRNA encapsulation efficiency of about90%. The findings revealed that polyzwitterionic PMPC-LNPs@siRNA absorbed protein corona with the main component of Vitronectin, mediating lung-targeted delivery of siRNA. With good cellular uptake and endo/lysosomal escape ability, in vitro and in vivo studies demonstrated that polyzwitterionic PMPC-LNPs with siRNA against tumor necrosis factor-α (TNF-α) could significantly down-regulate the TNF-α in mRNA and protein levels, and improved the pathological features of lung inflammation. Polyzwitterionic PMPC-LNPs@siRNA achieved safe and efficient treatment of lung inflammation. Therefore, this work offered a promising siRNA therapeutic approach for lung diseases.

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