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我国省域卫生资源与医疗压力的时空分异格局和脱钩关系演化

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中国卫生政策研究 2024年第2期17卷 23-31页

作者：索云龙付谦冯占春华中科技大学同济医学院医药卫生管理学院湖北武汉430030

目的:明晰省域卫生资源与医疗压力时空特征与变动趋势,为我国卫生健康事业高质量发展提供建议。方法:基于2010—2020年全国31个省份面板数据,构建省域卫生资源与医疗压力综合评价体系,采用全局熵值法与探索性空间分析揭示两者时空分异... 详细信息

目的:明晰省域卫生资源与医疗压力时空特征与变动趋势,为我国卫生健康事业高质量发展提供建议。方法:基于2010—2020年全国31个省份面板数据,构建省域卫生资源与医疗压力综合评价体系,采用全局熵值法与探索性空间分析揭示两者时空分异与关联格局,并引入Tapio脱钩指数阐释其演化特征与趋势。结果:观测期内,我国绝大多数省份卫生资源和医疗压力稳中略升,二者具备空间正相关与聚集性特征,并同经济发展与人口需求关系密切;全国主流脱钩状态由负脱钩向正脱钩转变,递进脱钩态势明显,区域卫生发展持续向好。结论与建议:各省份需结合本省卫生事业发展现状,注重要素与结构的时空耦合,以优化卫生资源配置结构与增强卫生体系韧性为抓手发挥区域卫生体系的比较优势。

关键词：卫生资源医疗压力时空分异脱钩指数

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国家植物园龙年新春兰花展

北京园林 2024年第1期40卷 66-66,F0003页

作者： JGNIAN XIN chun LAN HUA zhan 不详

Recent advance on the efficiency at maximum power of heat engines

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Chinese Physics B 2012年第2期21卷 36-45页

作者： Tu zhan-chun Department of Physics Beijing Normal UniversityBeijing 100875China

This review reports several key advances on the theoretical investigations of efficiency at maximum power of heat engines in the past five years. The analytical results of efficiency at maximum power for the Curzon-Ahlborn heat engine, the stochastic heat engine constructed from a Brownian particle, and Feynman＇s ratchet as a heat engine are presented. It is found that： the efficiency at maximum power exhibits universal behavior at small relative temperature differences; the lower and the upper bounds might exist under quite general conditions; and the problem of efficiency at maximum power comes down to seeking for the minimum irreversible entropy production in each finite-time isothermal process for a given time.

关键词： effciency at maximum power heat engine universality bounds

Abstract models for heat engines

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Frontiers of physics 2021年第3期16卷 99-110页

作者： zhan-chun Tu Department of Physics Beijing Normal UniversityBeijing100875China

We retrospect three abstract models for heat engines which include a classic abstract model in textbook of thermal physics,a primary abstract model for finite-time heat engines,and a refined abstract model for finite-time heat *** detailed models of heat engines in literature of finite-time thermodynamics may be mapped into the refined abstract *** future developments based on the refined abstract model are also surveyed.

关键词： abstract model heat engine finite-time thermodynamics

合成方法对富锂锰基正极材料Li_(1.2)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2)电化学性能的影响

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稀有金属与硬质合金 2024年第1期52卷 99-105页

作者：石沁灵王立帆詹纯北京科技大学冶金与生态工程学院北京100083

采用共沉淀法、溶胶凝胶法和固相法合成了富锂锰基正极材料Li_(1.2)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2),并通过XRD、SEM、EDS等对所合成材料的物相结构和微观组织等进行了表征,采用电池测试系统对由合成材料组装的CR2032纽扣式半电池进... 详细信息

采用共沉淀法、溶胶凝胶法和固相法合成了富锂锰基正极材料Li_(1.2)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2),并通过XRD、SEM、EDS等对所合成材料的物相结构和微观组织等进行了表征,采用电池测试系统对由合成材料组装的CR2032纽扣式半电池进行电化学性能测试。研究表明,三种合成方法都成功合成了具有层状结构的富锂锰基正极材料,其中共沉淀法制备的样品阳离子混排程度最低,元素分布和颗粒大小均匀,晶界边缘清晰,并且无明显团聚。从电化学性能来看,在2.0~4.8 V的电压范围内,0.1 C倍率下共沉淀法合成样品的首圈放电比容量最高,在充放电循环100圈后,仍保持195.8 mA·h/g的放电比容量,容量保持率为87.3%。相较而言,溶胶凝胶法和固相法制备的样品容量保持率较低,分别为84.5%和83.8%。与溶胶凝胶法和固相法制备样品相比,共沉淀法可有效提高Li_(1.2)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2)正极材料中Li^(+)的传输效率,进而提高样品的倍率性能。

关键词：锂离子电池富锂锰基正极材料合成方法电化学性能

Isomeric Fluorene-based Heteroundecenes with Different Side Chains Anchoring Positions for Small Molecule Acceptors

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Journal of Wuhan University of Technology(Materials Science) 2022年第1期37卷 136-147页

作者： WANG Wei zhan chun XIAO Shengqiang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Two isomeric fluorene-based heteroundecenes of bis(thienocyclopenthieno[3,2-b]thieno)fluorene(BT2T-F)and bis(dithieno[3,2-b:2’,3’-d]thiophene)cyclopentafluorene(B3T-F)have been designed and *** side chains of 4-hexylphenyl anchor on the 5th and 8th positions in B3T-F while on the 4th and 9th positions in BT2T-F,in which the former is closer to the center of the fused *** corresponding acceptor-donor-acceptor(A-D-A)type small molecule acceptors(SMAs)of BT2T-FIC and B3T-FIC were prepared by linking BT2T-F and B3T-F as fused ring donor units with the acceptor unit of 2-(5,6-difluoro-3-oxo-2,3-dihydroinden-1-ylidene)malononitrile(IC-2F),respectively.B3T-FIC presents a superior crystallinity with intense face-on π-π stacking in its neat film while BT2T-FIC is more *** blended with PBDB-T-2Cl as a polymer donor,the optimized PBDB-T-2Cl:BT2T-FIC device exhibits an averaged power conversion efficiency(PCE)of 10.56%while only 7.53%in the PBDB-T-2Cl:B3T-FIC *** improved short-circuit current(J_(sc))and fill factor(FF)of the PBDB-T-2Cl:BT2T-FIC device are the main contribution of its higher performance,which is attributed to its more efficient and balanced charge transport and better carrier recombination *** that BT2T-FIC blend and B3T-FIC blend films both take a preferential face-on orientatedπ-πstacking with comparable distances,the suitable SMA domain size obtained in the BT2T-FIC blend could account for its more efficient photovoltaic *** results highlight the importance of side-chain strategy in developing efficient SMAs with huge fused ring cores.

关键词： polymer solar cells small molecule acceptor side chains morphology

A Possible Generalized Form of Jarzynski Equality

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Communications in Theoretical Physics 2006年第5X期46卷 886-890页

作者： TU zhan-chun ZHOU Zi-Cong Department of Physics Tamkang University Tamsui 25137 Taiwan China Physics Division National Center for Theoretical Sciences at Taipei National Taiwan University Taipei 10617 Taiwan China

The crucial condition in the derivation of the Jarzynski equality （JE） from the fluctuation theorem is that the time integral of the phase space contraction factor can be exactly expressed as the entropy production resulting from the heat absorbed by the system from the thermal bath. For the system violating this condition, a more general form of JE may exist. This existence is verified by three Gedanken experiments and numerical simulations, and may be confirmed by the real experiment in the nanoscale.

关键词： Jarzynski equality fluctuation theorem entropy production

267例儿童嗜酸粒细胞性胃肠道疾病临床特征分析:一项多中心研究

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中国当代儿科杂志 2024年第2期26卷 139-144页

作者：詹春雷游洁玉李小芹汪勇梅贤琴万盛华江西省儿童医院消化科江西南昌330000 湖南省儿童医院消化营养科湖南长沙410007 河南省儿童医院消化科河南郑州450018

目的探讨儿童嗜酸粒细胞性胃肠道疾病(eosinophilic gastrointestinal disease,EGID)的临床表现、内镜下改变、病理组织学改变、治疗及预后特点,以提高儿科医师对该疾病的认识。方法前瞻性收集2019年1月—2022年7月江西省儿童医院、湖... 详细信息

目的探讨儿童嗜酸粒细胞性胃肠道疾病(eosinophilic gastrointestinal disease,EGID)的临床表现、内镜下改变、病理组织学改变、治疗及预后特点,以提高儿科医师对该疾病的认识。方法前瞻性收集2019年1月—2022年7月江西省儿童医院、湖南省儿童医院、河南省儿童医院确诊的267例EGID患儿资料,观察其发病年龄、症状、体征、实验室检查、内镜下改变、病理组织学改变及治疗的预后情况。结果267例EGID患儿中,临床分度以轻度(164例,61.4%)和中度(96例,35.6%)为主。各年龄均可发病,以学龄期儿童(178例)为主。婴儿期主要表现为呕吐、呕血,幼儿期主要表现为呕吐、便血,学龄前期和学龄期主要表现为腹痛、呕吐。血常规示近一半(49.4%)患儿出现血小板升高,但轻、中、重度EGID患儿血小板计数比较差异无统计学意义(P>0.05)。EGID患儿消化道内镜下无显著特异性改变,组织病理亦无特异性结构损伤。其中85.0%(227例)予以抑酸治疗,34.5%(92例)予以饮食回避,20.9%(56例)予以抗过敏药物治疗,少部分(24例,9.0%)使用泼尼松治疗。治疗后患儿临床症状均得到缓解,3例以消化性溃疡为表现者停药后症状出现反复。结论儿童EGID以轻、中度多见,内镜下改变无明显特异性,饮食回避及抑酸、抗过敏药物为主要治疗方法,预后良好。

关键词：嗜酸粒细胞性胃肠道疾病临床特征儿童

Synthesis and Photovoltaic Properties of A Dithieno[6,5-b：10,11-b＇]-8H-Cyclopentyl[1,2-b：4,3-b＇]Diphenanthrene based Donor-Acceptor Alternating Copolymer

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Journal of Wuhan University of Technology(Materials Science) 2018年第2期33卷 288-295页

作者：杨明焱 xia fei zhan chun 肖生强 State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 China

A novel fused nonacyclic monomer of dithieno[6,5-b：10,11-b＇]-8 H-cyclopentyl[1,2-b：4,3-b＇]diphenanthrene（DTCPDP） was synthesized by combining the structural features of ladder-type and multiple fused multi-cyclic aromatics. DTCPDP has a single sp3-hybridized carbon bridge between fused multi-cyclic aromatics. The copolymerization of DTCPDT with the electron accepting unit of 4,7-di（thiophen-2-yl）benzo[c][1,2,5]thiadiazole（DTBT） via Stille coupling afforded a novel donor-acceptor（D-A） alternating copolymer PDTCPDT-DTBT. The copolymer exhibited good chemical and thermal stabilities, with an optical band gap of 1.82 eV and a low-lying highest occupied molecular orbital（HOMO） energy level of-5.32 eV. When the copolymer was incorporated into polymer： fullerene（PC_（71）BM） blends to fabricate bulk heterojunction polymer solar cell devices, the devices exhibited a moderate maximum power conversion efficiency（PCE） of 5.90%.

关键词： polymer solar cells bulk heterojunction ladder-type conjugated polymers