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电子健康技术在心力衰竭患者居家管理中的应用进展

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中国全科医学 2024年第26期27卷 3212-3217页

作者：陈科君杨怡菲宫静杨滨旭周静遵义医科大学第二附属医院贵州省遵义市563000 遵义医科大学贵州省遵义市563000

心力衰竭是一种严重危害全球居民健康的心血管疾病,具有慢性、迁延性的病程特点,以居家为核心的有效管理是控制症状和改善患者预后的关键。电子健康(e-health)技术是心力衰竭居家管理研究领域的热点之一,具有突破时间、空间壁垒的优势,... 详细信息

心力衰竭是一种严重危害全球居民健康的心血管疾病,具有慢性、迁延性的病程特点,以居家为核心的有效管理是控制症状和改善患者预后的关键。电子健康(e-health)技术是心力衰竭居家管理研究领域的热点之一,具有突破时间、空间壁垒的优势,能够实现居家患者健康状态连续监测、智能评估、动态管理。本文对心力衰竭患者居家管理e-health相关研究进行系统梳理,探讨其在心力衰竭患者药物管理、运动康复、症状管理、风险预测以及其他方面的应用价值,同时对e-health系统数字包容性欠佳、运转体系不完善、数据安全存在风险等局限进行分析及展望,旨在为创新心力衰竭患者居家管理模式提供借鉴。

关键词：心力衰竭电子健康居家管理移动医疗综述

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Super-simple （5, 4）-GDDs of group type g^u

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Frontiers of Mathematics in China 2014年第5期9卷 1001-1018页

作者： Guangzhou chen kejun chen Yong ZHANG College of Mathematics and Information Science Henan Normal University Xinxiang 453007 China Department of Mathematics Taizhou University Taizhou 225300 China School of Mathematical Sciences Yancheng Teachers University Yancheng 224002 China

In statistical planning of experiments, super-simple designs are the ones providing samples with maximum intersection as small as possible. Super- simple group divisible designs are useful in constructing other types of super- simple designs which can be applied to codes and designs. In this article, the existence of a super-simple （5, 4）-GDD of group type gU is investigated and it is shown that such a design exists if and only if u ≥ 5, g（u - 2） ≥ 12, and u（u - 1）g^2≡ 0 （mod 5） with some possible exceptions.

关键词： Super-simple design group divisible design (GDD) balancedincomplete block design orthogonal array completely reducible

从富含缺陷的碳载体到酞菁钴的质子供给用于增强CO_(2)电还原

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Chinese Journal of Catalysis 2024年第7期62卷 190-197页

作者：梅子雯陈克军谭耀刘秋文陈琴王其忧汪喜庆蔡超刘康傅俊伟刘敏中南大学物理学院湖南省二氧化碳绿色资源化利用国际联合研究中心湖南长沙410083

利用可再生电力将二氧化碳转化为高附加值产品的电催化二氧化碳还原反应(CO_(2)RR)是一项具有革命性潜力的技术,因而备受关注.其中,一氧化碳被视为CO_(2)RR中最具经济效益的产物之一,可直接利用费托合成工艺将其用于合成醛、酮、烃类等... 详细信息

利用可再生电力将二氧化碳转化为高附加值产品的电催化二氧化碳还原反应(CO_(2)RR)是一项具有革命性潜力的技术,因而备受关注.其中,一氧化碳被视为CO_(2)RR中最具经济效益的产物之一,可直接利用费托合成工艺将其用于合成醛、酮、烃类等产品.酞菁钴(CoPc)作为单位点催化剂,因其高原子利用率和高催化选择性能,在二氧化碳转化为一氧化碳过程中具有很大优势.然而,CoPc无法为CO_(2)RR中的质子化过程提供足够质子,导致其在工业大电流密度下的效率较低.因此,探索一种能够解决CO_(2)RR中质子供给不足问题的高效电催化剂对于提升CO_(2)RR的性能至关重要.本文设计了具有增强质子供给作用的缺陷碳纳米管(d-CNT),将其作为导电载体分散CoPc,用于制备CoPc/d-CNT电催化剂.通过引入富缺陷的碳纳米管(d-CNT),加速水解离进而增加CO_(2)RR的质子供给量.X射线光电子能谱、X射线吸收近边光谱和扩展X射线吸收精细结构谱结果表明,CoPc/d-CNT成功合成,同时保留了CoPc完整的Co-N4配位结构.透射电镜、粉末X射线衍射谱和拉曼光谱共同表明,d-CNT表面缺陷相对于商用CNT明显增加.动力学实验和原位衰减全反射表面增强红外吸收光谱研究表明,含大量缺陷的d-CNT具有加速水解离的能力,显著提高了二氧化碳还原反应过程中的质子供给,从而促进了CoPc_上CO_(2)活化生成*COOH.同时,密度泛函理论计算结果表明,d-CNT表面缺陷位点上从吸附水(*H2O)到质子水(H3O+)的吉布斯自由能为0.74 eV,远低于CNT(超过2 eV),表明d-CNT促进了水解过程和质子传递,再次证实了d-CNT降低了水分子解离的势垒.通过实验和理论的共同验证,阐明了d-CNT中的缺陷能够促进水解离,改善CO_(2)RR反应过程中质子供给,增强CoPc高效催化CO_(2)RR的能力.因此,CoPc/d-CNT混合材料表现出较好的催化性能.在电流密度为500 mA cm^(-2)的流动电池中,CoPc/d-CNT的CO法拉第效率(FECO)高达96%.相对而言,CoPc/CNT在200 mA cm^(-2)时FECO已经下降到90%以下.此外,在150 mA cm^(-2)的电流密度下,CoPc/d-CNT能够在20 h内维持FECO超过90%.综上,本文通过引入具有水解离能力的缺陷碳位点,解决了单位点催化剂CoPc在CO_(2)RR中质子供给不足的问题,为设计高性能催化剂提供了新见解.

关键词：碳缺陷二氧化碳还原反应酞菁钴质子供给电催化

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低噪声水声信号前置放大器设计

湖北大学学报（自然科学版） 2024年第2期46卷 282-288页

作者：程华陈科君王旭光海鹰企业集团有限责任公司江苏无锡214111 湖北大学人工智能学院湖北武汉430062

水下信息的发送与接收主要通过声信号的传播,水听器作为常用的水声信号接收装置,需要前置放大器来提高所获取信号的质量。文中选用AD8421仪表放大器芯片与OP2177精密运算放大器芯片设计了一种低噪声水声信号前置放大器,该电路增益为26 ... 详细信息

水下信息的发送与接收主要通过声信号的传播,水听器作为常用的水声信号接收装置,需要前置放大器来提高所获取信号的质量。文中选用AD8421仪表放大器芯片与OP2177精密运算放大器芯片设计了一种低噪声水声信号前置放大器,该电路增益为26 dB,工作带宽为100 Hz~20 kHz,输出信号为差分形式,同时具有小体积、低功耗的特点。通过连接某型压电水听器,测试了电路工作性能以及对水听器信号的调理效果。实测结果表明,该前置放大器能满足设计技术指标要求,在实际工作中取得了良好的效果。

关键词：水声信号调理前置放大器低噪声有源滤波器带通滤波器

Recent advances in the utilization of copper sulfide compounds for electrochemical CO2 reduction

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纳米材料科学：英文版 2020年第3期2卷 235-247页

作者： Yingkang chen kejun chen Junwei Fu Akira Yamaguchi Hongmei Li Hao Pan Junhua Hu Masahiro Miyauchi Min Liu State Key Laboratory of Powder Metallurgy Shenzhen Research InstituteSchool of Physics and ElectronicsCentral South UniversityPR China Department of Periodontics&Oral Mucosal Section Xiangya Stomatological HospitalCentral South University72 Xiangya RoadChangsha410008HunanPR China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou450002PR China Department of Materials Science and Engineering School of Materials and Chemical TechnologyTokyo Institute of Technology2-12-1 OokayamaMeguro-kuTokyo152-8552Japan

Converting carbon dioxide(CO2)into value-added chemicals by CO2 reduction has been considered as a potential way to solve the current energy crisis and environmental *** the methods of CO2 reduction,the electrochemical method has been widely used due to its mild reaction condition and high reaction *** the electrochemical reduction system,the CO2 electrocatalyst is the most important *** many CO2 electrocatalysts have been developed,efficient catalysts with high activity,selectivity and stability are still *** sulfide compound,as a low-toxicity and emerging material,has broad prospects in the field of CO2 reduction due to its unique structural and electrochemical *** progress has been achieved with copper sulfide nanocrystalline and the field is rapidly *** paper summarizes the preparation,recent progress in development,and factors affecting the electrocatalytic CO2 reduction performance with copper sulfide compound as a *** for future development are also outlined,with the aim of using copper sulfide compound as a highly active and stable electrocatalyst for CO2 reduction.

关键词： CO2 reduction Copper sulfide compound Electrocatalyst Product selectivity

Pulsed Laser Annealed Ga Hyperdoped Poly-Si/SiO_(x)Passivating Contacts for High-Efficiency Monocrystalline Si Solar Cells

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Energy & Environmental Materials 2023年第3期6卷 388-399页

作者： kejun chen Enrico Napolitani Matteo De Tullio Chun-Sheng Jiang Harvey Guthrey Francesco Sgarbossa San Theingi William Nemeth Matthew Page Paul Stradins Sumit Agarwal David L.Young Colorado School of Mines 1500 Illinois StGolden Colorado 80401USA Dipartimento di Fisica e Astronomia and CNR-IMM Universit`a degli Studi di Padovavia Marzolo 8PadovaItaly National Renewable Energy Laboratory 15013 Denver West ParkwayGolden Colorado 80401USA

Polycrystalline Si(poly-Si)-based passivating contacts are promising candidates for high-efficiency crystalline Si solar *** show that nanosecond-scale pulsed laser melting(PLM)is an industrially viable technique to fabricate such contacts with precisely controlled dopant concentration profiles that exceed the solid solubility *** demonstrate that conventionally doped,hole-selective poly-Si/SiO_(x)contacts that provide poor surface passivation of c-Si can be replaced with Ga-or B-doped contacts based on non-equilibrium *** overcome the solid solubility limit for both dopants in poly-Si by rapid cooling and recrystallization over a timescale of∼25 *** show an active Ga dopant concentration of∼3×10^(20)cm^(−3)in poly-Si which is six times higher than its solubility limit in c-Si,and a B dopant concentration as high as∼10^(21) cm^(−3).We measure an implied open-circuit voltage of 735 mV for Ga-doped poly-Si/SiO_(x)contacts on Czochralski Si with a low contact resistivity of 35.5±2.4 mΩcm^(2).Scanning spreading resistance microscopy and Kelvin probe force microscopy show large diffusion and drift current in the p-n junction that contributes to the low contact *** results suggest that PLM can be extended for hyperdoping of other semiconductors with low solubility atoms to enable high-efficiency devices.

关键词： Ga hyperdoping Ga passivating contacts poly-Si/SiO_(x) pulsed laser melting silicon solar cell

Regulating local charges of atomically dispersed Moδ+ sites by nitrogen coordination on cobalt nanosheets to trigger water dissociation for boosted hydrogen evolution in alkaline media

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Journal of Energy Chemistry 2022年第9期31卷 125-132,I0004页

作者： Maoqi Cao Kang Liu Yao Song Chao Ma Yiyang Lin Huangjingwei Li kejun chen Junwei Fu Hongmei Li Jun Luo Yida Zhang Xusheng Zheng Junhua Hu Min Liu School of Chemistry and Chemical Engineering Qiannan Normal University for NationalitiesDuyun 558000GuizhouChina State Key Laboratory of Powder Metallurgy School of Physics and ElectronicsShenzhen Research InstituteSchool of Physical and ElectronicsCentral South UniversityChangsha 410083HunanChina School of Materials Science and Engineering Central South University of Forestry and TechnologyChangsha 410004HunanChina School of Materials Science and Engineering Hunan UniversityChangsha 410082HunanChina National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029AnhuiChina School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001HenanChina

Now,Pt-based materials are still the best catalysts for hydrogen evolution reaction(HER).Nevertheless,the scarcity of Pt makes it impossible for the large-scale applications in *** cobalt is taken as an excellent HER catalyst due to its suitable H*binding,its alkali HER catalytic property need to be improved because of the sluggish water dissociation *** this work,nitrogen with small atomic radius and metallophilicity is employed to adjust local charges of atomically dispersed Mo^(δ+)sites on Co nanosheets to trigger water *** calculations suggest that the energy barrier of water dissociation can be effectively reduced by introducing nitrogen coordinated Mo^(δ+)*** realize this speculation,atomically dispersed Mo^(δ+)sites with nitrogen coordination of Mo(N)/Co were prepared via reconstruction of CoMoO_(4).High angle annular dark-field scanning transmission electron microscopy(HAADF-STEM)and X-ray absorption spectroscopy(XAS)demonstrate the coordination of N atoms with atomically dispersed Mo atoms,leading to the local charges of atomically dispersed Mo^(δ+)sites in Mo(N)/*** measurement from ambient pressure X-ray photoelectron spectroscopy(AP-XPS)reveals that the Mo^(δ+)sites promote the adsorption and activation of water ***,the Mo(N)/Co exhibits an excellent activity,which need only an overpotential of 39 mV to reach the current density of 10 mA cm^(-2).The proposed strategy provides an advance pathway to design and boost alkaline HER activity at the atomic-level.

关键词： Charge localized Mo Nitrogen coordination Co nanosheet Water dissociation Alkaline HER

Synergetic pathways of water-energy-carbon in ecologically vulnerable regions aiming for carbon neutrality:a case study of Shaanxi,China

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Frontiers of Environmental Science & Engineering 2024年第9期18卷 1-15页

作者： Yingying Liu Hanbing Li Sha chen Lantian Zhang Sumei Li He Lv Ji Gao Shufen Cui kejun Jiang Department of Environmental Science Key Laboratory of Beijing on Regional Air Pollution ControlBeijing University of TechnologyBeijing 100124China China Metallurgical Industry Planning and Research Institute Beijing 100711China Environmental Defense Fund Beijing 100007China Department of Financial Management Lishui UniversityLishui 323000China Energy Research Institute Beijing 100038China

Synergetic energy-water-carbon pathways are key issues to be tackled under carbon-neutral target and high-quality development worldwide,especially in ecologically vulnerable regions(EVRs).In this study,to explore the synergistic pathways in an EVR,a water-energy-carbon assessment(WECA)model was built,and the synergistic effects of water-energy-carbon were comprehensively and quantitatively analyzed under various scenarios of regional *** Province was chosen as the representative EVR,and Lower challenge(LEC)and Greater challenge(GER)scenarios of zerocarbon transition were set considering the technological maturity and regional energy *** results showed that there were limited effects under the zero-carbon transition of the entire region on reducing water withdrawals and improving the water *** the LEC scenario,the energy demand and CO2 emissions of Shaanxi in 2060 will decrease by 70.9%and 99.4%,respectively,whereas the water withdrawal and freshwater aquatic ecotoxicity potential(FAETP)will only decrease by 8.9%and 1.6%,*** could be attributed to the stronger demand for electricity in the energy demand sector caused by industrial transition *** GER scenario showed significant growth in water withdrawals(16.0%)and FAETP(36.0%)because of additional biomass *** promote the synergetic development of regional transition,EVRs should urgently promote zero-carbon technologies(especially solar and wind power technologies)between 2020 and 2060 and dry cooling technology for power generation before *** particular,a cautious attitude toward the biomass energy with carbon capture and storage technology in EVRs is strongly recommended.

关键词： Carbon neutrality Water withdrawals Water environment quality Ecologically vulnerable region Typical regional transition

基于广义标准轨迹的平衡滑翔状态反馈制导方法

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国防科技大学学报 2012年第2期34卷 134-140页

作者：刘君陈克俊汤国建国防科技大学航天与材料学院湖南长沙410073

对多约束条件下远程助推滑翔飞行器再入滑翔飞行问题,提出了一种基于广义标准轨迹的平衡滑翔状态反馈制导方法。建立了远程助推滑翔飞行器的动力学模型,确定了飞行轨迹约束条件,详细阐述了基于广义标准轨迹的平衡滑翔状态反馈制导方法... 详细信息

对多约束条件下远程助推滑翔飞行器再入滑翔飞行问题,提出了一种基于广义标准轨迹的平衡滑翔状态反馈制导方法。建立了远程助推滑翔飞行器的动力学模型,确定了飞行轨迹约束条件,详细阐述了基于广义标准轨迹的平衡滑翔状态反馈制导方法的制导原理,设计了远程助推滑翔飞行器的侧向和纵向制导律,并采用LQR(linear quadratic regular)方法设计了纵向制导参数,仿真验证了该方法的可行性。与以往再入滑翔制导方法不同,该制导方法主要利用飞行攻角的变化来调节飞行轨迹,飞行过程中飞行器的速度倾侧角较小。仿真结果表明,该制导方法能满足远程助推滑翔飞行器的再入滑翔制导问题,并且具有较好的鲁棒性和自适应性。

关键词：广义标准轨迹平衡滑翔制导方法 LQR方法