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Solid solution strategy modulated defects engineering of(Cr_(1-x)V_(x))_(2)AlC MAX phase toward superior electromagnetic wave absorption

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Rare Metals 2024年第7期43卷 3205-3219页

作者： ji-lin Gou Yu-Kai Chang Shu liu Peng-Hui li ping-Hao Cui Qian-Ku Hu li-Bo Wang Xin Zhang Jun-Kai Wang Qi-Xun Xia Ai-Guo Zhou School of Materials Science and Engineering Henan Polytechnic UniversityJiaozuo 454003China Key Laboratory for Microstructural Material Physics of Hebei Province School of ScienceYanshan UniversityQinhuangdao 066004China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China

Defects engineering is an effective strategy for manipulating electromagnetic parameters and enhancing electromagnetic wave(EMW)absorption ***,the relationship between them is not clear,especially in solid solution *** this work,a series of(Cr_(1-x)V_(x))_(2)AlC MAX phase solid solutions with layered structure were prepared via tuning the ratio of Cr and V to explore their EMW absorption *** experimental results indicated that the doping of V atoms at the M-site could effectively regulate its impedance matching and EMW absorption properties by introducing appropriate numbers of defects in the crystal,such as twin boundaries,dislocations and lattice *** them,if Cr:V=3:1,Cr_(1.5)V_(0.5)AlC,as radar absorption materials,could reach a strong reflection loss of-51.8 dB at the frequency of 12.8 GHz under an ultra-thin thickness of 1.3 *** reflection loss value could attain-10 dB in a wide frequency range of 2.7-18 GHz and thickness range of 1-5 *** addition,after high temperature and acid-alkali immersion treatment,this sample still had good EMW absorption capability,and the effective absorption bandwidth was enhanced from 2.3 to 2.6 GHz after concentrated acid immersion or 3.1 GHz after concentrated alkali *** work has great reference significance for the research and development of high-performance MAX-based EMW absorption materials in harsh environments.

关键词： MAX phases Solid solution Defects engineering Electromagnetic wave absorption Harsh environments

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略论当代西方国家行政领导模式的嬗变

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行政论坛 2010年第1期17卷 92-95页

作者：纪丽萍南京师范大学公共管理学院南京210097

新公共管理中"企业家政府"力主"掌舵"的行政领导模式,政府行政领导效能由此明显改观,并且推进了治理变革,但也造成参与价值的隐去、社会公平的缺失与治理易于失灵等问题。后新公共管理"整体政府"改革由此尝试"共享领导"的新型行政领导模... 详细信息

新公共管理中"企业家政府"力主"掌舵"的行政领导模式,政府行政领导效能由此明显改观,并且推进了治理变革,但也造成参与价值的隐去、社会公平的缺失与治理易于失灵等问题。后新公共管理"整体政府"改革由此尝试"共享领导"的新型行政领导模式,并将其内涵界定为鼓励公众参与公共决策、增进公共服务均等化以及实施愿景型领导等几方面,从而相应弥补了企业家政府掌舵模式所存在的诸多缺陷。

关键词：行政领导模式企业家政府掌舵整体政府共享领导西方国家

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Threshold Selection and Resource Allocation for Quantized Identification

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Journal of Systems Science & Complexity 2024年第1期37卷 204-229页

作者： WANG Ying li Xin ZHAO Yanlong ZHANG ji-Feng Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

This paper is concerned with the optimal threshold selection and resource allocation problems of quantized identification, whose aims are improving identification efficiency under limited resources. Firstly, the first-order asymptotically optimal quantized identification theory is extended to the weak persistent excitation condition. Secondly, the characteristics of time and space complexities are established based on the Cramér-Rao lower bound of quantized systems. On these basis, the optimal selection methods of fixed thresholds and adaptive thresholds are established under aperiodic signals, which answer how to achieve the best efficiency of quantized identification under the same time and space complexity. In addition, based on the principle of maximizing the identification efficiency under a given resource, the optimal resource allocation methods of quantized identification are given for the cases of fixed thresholds and adaptive thresholds, respectively, which show how to balance time and space complexity to realize the best identification efficiency of quantized identification.

关键词： Quantized output resource allocation system identification threshold selection.

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苏州文化遗产保护中的政府多维职能

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南通大学学报（社会科学版） 2014年第4期30卷 30-34页

作者：纪丽萍南京航空航天大学人文与社会科学学院江苏南京210016

保护文化遗产已成为当前我国地方政府的重要职能。因存在"碎片化"缺陷,我国地方政府的文化遗产保护职能必须进行重构。苏州在文化遗产保护方面成效显著,这归因于苏州市政府经过职能转变已形成了文化遗产保护的多维治理机制:从包办到服务... 详细信息

保护文化遗产已成为当前我国地方政府的重要职能。因存在"碎片化"缺陷,我国地方政府的文化遗产保护职能必须进行重构。苏州在文化遗产保护方面成效显著,这归因于苏州市政府经过职能转变已形成了文化遗产保护的多维治理机制:从包办到服务;从主体到主导;从封闭到开放,从分散到整合;从传统到创新。此种多维治理机制可以为我国地方政府文化遗产保护职能的转变提供一些有益启示。

关键词：文化遗产地方政府文化自觉文化认同

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Salinity Acclimation Induces Reduced Energy Metabolism,Osmotic Pressure Regulation and Transcriptional Reprogramming in Hypotrichida Ciliate Gastrostyla setifera

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Journal of Ocean University of China 2024年第2期23卷 539-549页

作者： ji Xin BI Luping ZOU Songbao li Wenlu ji Daode ZHANG Qianqian School of Ocean Yantai UniversityYantai 264005China Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003China Zhejiang Institute of Freshwater Fisheries Huzhou 313001China Muping Coastal Environment Research Station Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264117China

Coastal and estuarine protists are frequently exposed to salinity *** the tolerance and stress responses of microalgae to salinity have been extensively studied,there have been scarce studies on the physiological response of heterotrophic protists to salinity *** this study,we investigated the physiological response of the heterotrophic ciliate Gastrostyla setifera to a salinity of 3,via a transcriptomic *** first transcriptome of genus Gastrostyla was obtained utilizing a group of manually isolated ciliate individuals(cells)and RNA-seq *** completeness of the transcriptome was *** expressed gene(DEG)analysis was performed among the transcriptomes of *** acclimated in saline water(salinity 3)and those cultured in fresh *** results demonstrated a significant alternation in gene transcription,in which the ciliate exhibits a transcripttomic acclimation in responding salinity *** up-regulated DEGs were enriched in the pathways of cytoskeleton proteins,membrane trafficking,protein kinases and protein *** may represent enhanced functions of ion transport,stress response and cell *** involved in energy metabolism and biosynthesis were markedly down-regulated,reflecting decreased cell ***,we detected significantly down-regulated genes involved in several pathways of amino acid catabolism,which may lead to accumulation of amino acids in the ciliate *** acid could act as compatible solutes in the cytoplasm to maintain the osmotic balance in saline ***,this work is an initial exploration to the molecular basis of the heterotrophic protist responding to salinity *** result sheds light on the mechanisms of enhancement of cell protection,reduction of cell activity,and osmotic pressure regulation in ciliates acclimated to salinity.

关键词： salinity stress heterotrophic protist ciliate Gastrostyla setifera transcriptome differentially expressed gene

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Effect of Annealing Ways on the Formation of Cube Texture in Ni-5at% W Substrates for YBCO Coated Conductors

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稀有金属材料与工程 2011年第S3期40卷 322-324页

作者： Chen Xingpin1, Shang Du1, Chen Xue1, ji Yongbin2, ji ping2, li Chengshan2, liu Qing1 1 Chongqing University, Chongqing 400030, China 2 Northwest Institute for Nonferrous Metal Research, Xi’an 710016, China Chongqing Univ Coll Mat Sci & Engn Chongqing 400030 Peoples R China NW Inst Nonferrous Met Res Xian 710016 Peoples R China

Two annealing ways, single-step annealing (SSA) and two-step annealing (TSA), were carried out to investigate the formation of the cube texture during recrystallization in the highly rolled Ni-5at%W alloy by means of EBSD and XRD techniques. It was found that both the microstructure and cube texture of the highly rolled substrates depended strongly on the annealing ways. The TSA method yields sharper cube texture and higher proportion of low-angle grain boundaries compared with SSA method. In addition, the TSA method suppresses the formation of annealing twins during recrystallization and improves the degree of the in-plane alignment of the cube grains in the alloy slightly.

关键词： cube texture nickel alloys recrystallization grain boundaries

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The mechanisms of enhanced thickness-dependent DC breakdown strength of EP/MWCNTs nanocomposites

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High Voltage 2024年第2期9卷 440-452页

作者： Zhen li He Gao Longfei Zhang Shouming Wang ji liu Shengtao li Key Laboratory of Engineering Dielectrics and Its Application Ministry of EducationHarbin University of Science and TechnologyHarbinChina State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityXi'anChina

Owing to advanced power electronic and electrical applications developing towards miniaturisation and integration,the thickness-dependent DC breakdown mechanism of epoxy/multiwall-carbon-nanotube nanocomposites is under *** results indicate that the breakdown strength of nanocomposites containing 0.05 wt%multiwall-carbon-nanotubes rises by~18%,and the breakdown strength falls exponentially with increasing *** clarify the microscopic mechanism,a simulation model of DC breakdown,including carriers transport and segmental dynamics,is developed,and the accordant simulation results with experimental results indicate that the thickness-dependent DC breakdown of epoxy/multiwall-carbon-nanotube nanocomposites is determined both by segment chain dynamics and charge *** to the breakdown model analysis,the effects of multiwall-carbon-nanotube on enhanced breakdown strength are caused by the increased amount of deep traps in the interfacial region,while the influence of thickness is attributed to the enlarged segment chain displacement and electric field distortion as the voltage raising time increases.

关键词： strength breakdown nanocomposites

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Application of PDCA in improving hand hygiene compliance and nosocomial infection quality in orthopedics

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Frontiers of Nursing 2024年第3期11卷 327-336页

作者： Ya-ping Su Rui-ling li Yuan-Yuan Wang Yu-Rui Zhang Ya-jie ji Nursing Teaching and Research Department School of Nursing and HealthHenan UniversityKaifengHenan 475004China Department of Continuing Education The First Affiliated Hospital of Henan UniversityKaifengHenan 475000China

Objective:To explore the effect of the Plan-Do-Check-Action(PDCA)cycle on hand hygiene and nosocomial infection quality of or thopedic medical ***:The whole year of 2021 was selected to monitor the quality of hand hygiene and ***-up monitoring and real-time recording during the period of morning shift and medical operation concentration time,and compare the compliance of hand hygiene before and after implementation,and evaluate the quality of nosocomial ***:The hand hygiene compliance of doctors and nurses in stage P was 82%.The compliance of medical staff in stage D was 93%.The compliance of stage C was 94%and that of stage A was 95%.The quality score of hospital self-examination nosocomial infection was also significantly ***:The PDCA management cycle can effectively improve the compliance of hand hygiene and the nosocomial infection quality,which is wor thy of circulatory application in or thopedic nosocomial infection quality control,especially improving the quality of hand hygiene.

关键词： hand hygiene quality improvement PDCA nosocomial infection infection control nursing management

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Current-carrying tribological behavior of C/Cu contact pairs in extreme temperature and humidity environments for railway catenary systems

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Science China(Technological Sciences) 2024年第8期67卷 2537-2548页

作者： SHEN MingXue ji DeHui HU Qiang XIAO li li Qiuping State Key Laboratory of Performance Monitoring and Protecting of Rail Transit Infrastructure East China Jiaotong UniversityNanchang 330013China School of Materials Science and Engineering East China Jiaotong UniversityNanchang 330013China Institute of Applied Physics Jiangxi Academy of SciencesNanchang 330095China

Many current-carrying contact pairs, such as those found in pantograph-catenary systems, operate in open environments and are susceptible to significant external interference from temperature and humidity variations. This study investigated the evolution of the friction coefficient and contact resistance of C/Cu contact pairs under alternating temperature, humidity, and current conditions. Through experimentation, the wear rate and microtopography of the worn surface were analyzed under various constant parameters. Subsequently, the differences in tribological behavior and current-carrying characteristics of the contact pairs under these three parameters were explored. The results revealed that the decrease in temperature resulted in a significant increase in the friction coefficient of the contact pairs, carbon wear, and copper surface roughness. Additionally, the surface oxidation rate was lower at lower temperatures. Moreover, contact resistance did not consistently increase with decreasing temperature, owing to the combined action of the contact area and the oxide film. Compared with temperature, humidity fluctuations at room temperature exerted less influence on the friction coefficient and contact resistance of the contact pairs. Dry environments rendered carbon materials vulnerable to oxidation and cracking, while excessive humidity fostered abrasive wear and arcing. High-current conditions generally degraded the tribological properties of C/Cu contacts. In the absence of current, the friction coefficient was extremely high, and the copper transfer was high. Under excessive current, copper was susceptible to plowing by carbon micro-bumps and abrasive particles, resulting in a decrease in the friction coefficient. The release of lipids from the carbon surface due to temperature elevation weakened the electrical contact performance and increased the occurrence of arc erosion, thereby exacerbating carbon wear.

关键词： temperature/humidity pantograph-catenary system C/Cu wear current-carrying friction sliding electrical contact

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Crystallization of RE_(2)(OH)_(2)CO_(3)SO_(4)·nH_(2)O as a new family of layered hydroxides(RE=Gd-Lu lanthanides and Y),derivation of RE_(2)O_(2)SO_(4),photoluminescence and optical thermometry

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Journal of Rare Earths 2024年第8期42卷 1496-1506,I0003页

作者： Fan li Zhenqi Song Zhiyuan Pan Sihan Feng Qi Zhu ji-Guang li Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China Research Center for Functional Materials National Institute for Materials ScienceTSsukuboaIbaraki3050044Japan

Layered rare-earth hydroxides(LREHs) draw wide research interest because of their peculiar crystal structure,rich interlayer chemistry and abundant functionality of the RE element,but are limited to the two categories of RE_(2)(OH)_(5)A·nH_(2)O(A:typical of Cl^(-)or NO_(3)^(-)) and RE_(2)(OH)_(4)SO_(4)·nH_(2)*** the other hand,rare-earth oxysulfates(RE_(2)O_(2)SO_(4)) have attracted attention due to their properties of large-capacity oxygen storage,low-temperature magnetism and luminescence,but their preparation procedure mostly involves toxic SO_(x) gases and/or complicated *** this work,RE_(2)(OH)_(2)CO_(3)SO_(4)·nH_(2)O as a new family of LREHs(RE=Gd-Lu lanthanides and Y) were produced via hydrothermal reaction,from which phase-pure RE_(2)O_(2)SO_(4) was derived via subsequent annealing at 800℃ in air without the involvement of SO_(x),The compounds were thoroughly characterized to reveal the intrinsic influence of lanthanide contraction(RE^(3+) radius) on crystal structure,thermal behavior(dehydroxylation/decarbonation/desulfurization),vibrational property and crystallite *** analyzing the photoluminescence of Eu^(3+) and Sm^(3+)in the Gd_(2)O_(2)SO_(4) typical host it is found that the 617 nm(Eu^(3+),λ_(ex)=275 nm) and 608 nm(Sm^(3+),λ_(ex)=407 nm) main emissions can retain as high as ^(7)9.6% and 85.5%of their room-temperature intensities at 423 K,with activation energies of ~0.19 and 0.21 eV for thermal quenching,*** also indicates that both the phosphors have the potential for optical temperature sensing via the fluorescence intensity ratio(FIR) technology,whose maximum relative sensitivity reaches -2.70%/K for Eu^(3+)and 1.73%/K for Sm^(3+) at 298 K.

关键词： Layered hydroxide RE_(2)O_(2)SO_(4) Luminescence Optical temperature sensing Rare earths

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