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Crystalline Structure-Dependent Mechanical and Thermoelectric Performance in Ag_(2)Se_(1‐x)S_(x)System

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Research 2020年第1期2020卷 1089-1098页

作者： Jiasheng Liang Pengfei Qiu Yuan Zhu Hui Huang zhiqiang gao Zhen Zhang Xun Shi Lidong Chen State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Division of Solid-State Electronics Department of Electrical EngineeringUppsala UniversityUppsalaSweden School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

Self-powered wearable electronics require thermoelectric materials simultaneously with a high dimensionless figure of merit(zT)and good flexibility to convert the heat discharged by the human body into ***_(2)(S,Se)-based semiconducting materials can well satisfy these requirements,and thus,they are attracting great attention in thermoelectric society ***_(2)(S,Se)crystalizes in an orthorhombic structure or monoclinic structure,depending on the detailed S/Se atomic ratio,but the relationship between its crystalline structure and mechanical/thermoelectric performance is still unclear to *** this study,a series of Ag_(2)Se_(1-x)S_(x)(x=0,0.1,0.2,0.3,0.4,and 0.45)samples were prepared and their mechanical and thermoelectric performance dependence on the crystalline structure was systematically investigated.x=0:3 in the Ag_(2)Se_(1-x)S_(x)system was found to be the transition boundary between orthorhombic and monoclinic *** property measurement shows that the orthorhombic Ag_(2)Se_(1-x)S_(x)samples are brittle while the monoclinic Ag_(2)Se_(1-x)S_(x)samples are ductile and *** addition,the orthorhombic Ag_(2)Se_(1-x)S_(x)samples show better electrical transport performance and higher zT than the monoclinic samples under a comparable carrier concentration,most likely due to their weaker electron-phonon *** study sheds light on the further development of flexible inorganic TE materials.

关键词： ductile crystalline attracting

基于CBCT研究伴牙周炎患者种植牙治疗同期行GBR技术对牙槽骨的影响

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影像科学与光化学 2022年第1期40卷 165-169页

作者：蒋菁高志强唐山职业技术学院河北唐山063000 唐山市协和医院口腔科河北唐山063000

本文探讨伴牙周炎患者种植牙同期行引导性骨再生(GBR)技术治疗对牙槽骨吸收的影响。选取接受牙种植同期行GBR技术治疗的患者90例作为研究对象,其中伴有牙周炎的患者有42例(牙周炎组)、不伴有牙周炎的患者有48例(对照组),采用CBCT观察两... 详细信息

本文探讨伴牙周炎患者种植牙同期行引导性骨再生(GBR)技术治疗对牙槽骨吸收的影响。选取接受牙种植同期行GBR技术治疗的患者90例作为研究对象,其中伴有牙周炎的患者有42例(牙周炎组)、不伴有牙周炎的患者有48例(对照组),采用CBCT观察两组的牙槽骨参数并进行比较。负载2年后(T2),牙周炎组患者的牙槽骨近中点、远中点、舌侧的牙槽骨高度测定值[(2.64±0.09)mm、(2.66±0.13)mm、(3.91±0.16)mm]均低于对照组的[(2.76±0.13)mm、(2.72±0.11)mm、(3.99±0.18)mm],且差异具有统计学意义(P<0.05);牙周炎组患者的牙槽嵴顶区舌侧、牙槽嵴顶区唇侧、根尖区舌侧的牙槽骨密度值[(1054.1±97.6)Hu、(1058.3±113.0)Hu、(989.1±98.0)Hu]均低于对照组的[(1147.3±133.0)Hu、(1103.0±86.3)Hu、(1067.6±103.8)Hu],且差异具有统计学意义(P<0.05)。与无牙周炎病史的患者相比,具有牙周炎病史的牙缺损患者接受牙种植同期行GBR技术治疗后种植体周围骨吸收更加的明显,CBCT技术能较好地观察到种植体周围骨吸收的情况。

关键词：锥形束CT 种植骨再生牙周炎牙槽骨

Pure aromatic hydrocarbons with meta-linked phenyl-core and perihedral fluorene substitutions with/without inert groups of tert-butyl： bipolar hosts for blue phosphorescence

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Science China Chemistry 2017年第2期60卷 223-230页

作者： gaowen Liu Chuanjun Wang Baoxiu Mi Minjie Zhuo Changjin Ou Jie Wang Shuchao Zheng Juan Song zhiqiang gao Dapeng Cao Key Laboratory for Organic Electronics and Information Displays & Institute of Advanced Materials (IAM) Jiangsu National Synergistic Innovation Center for Advanced Materials (SICAM) Nanjing University of Posts & Telecommunications Nanjing 210023 China. School of Material Science and Engineering Jiangsu Engineering Centre for Flat-Panel Displays & Solid-state Lighting Nanjing University of Posts &Telecommunications Nanjing 210023 China

Two pure hydrocarbon molecules of l,3,5-tris(9-phenyl-9H-fluoren-9-yl)benzene(mTPFB)and l,3,5-tris(2-tert-butyl-9-phenyl-9H-fluoren-9-yl)benzene(tBu-mTPFB)were *** to the conjugation blocked connection mode and rigid/bulky substitutions,these two materials possess high triplet energy,enabling them as good hosts for blue phosphor in *** studying their thermal,electrochemical,electronic absorption and photoluminescent properties,it was found that the influence of the inert tert-butyl group on material photoelectrical properties is *** instance,mTPFB and tBu-mTPFB showed very similar absorption and emission profiles,with almost the same bandgap,triplet energy and energy ***,the encapsulation of tert-butyl on the 2-position of 9-phenylfluorene enhanced material thermal *** importantly,carrier transport properties were improved dramatically,as proved by the mono carrier *** phosphorescent OLEDs hosted by tBu-mTPFB showed external quantum efficiency of 15.2%and current efficiency of 23.0 cd/A,which were much higher than that of the OLEDs based on mTPFB with the analogous structure.

关键词：磷光OLED 联苯基叔丁基惰性组蓝色电子吸收光谱主机双极

Mitogenomic phylogeny,biogeography,and cryptic divergence of the genus Silurus(Siluriformes:Siluridae)

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Zoological Research 2024年第4期45卷 711-723页

作者： Weitao Chen Nicolas Hubert Yuefei Li Shuli Zhu Jun Wang Denggao Xiang Shang gao Chunni Kou Jilong Wang Tai Wang zhiqiang Liang Junjie Wu Xinhui Li Jie Li Pearl River Fisheries Research Institute Chinese Academy of Fishery SciencesGuangzhouGuangdong 510380China China Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province GuangzhouGuangdong 510380China Key Laboratory of Prevention and Control for Aquatic Invasive Alien Species Ministry of Agriculture and Rural AffairsGuangzhouGuangdong 510380China Scientific Observing and Experimental Station of National Fisheries Resources and Environment GuangzhouGuangdong 510380China Institut de Recherche pour le Développement MontpellierUMR 226 ISEM(UM-CNRS-IRD)France State Key Laboratory of Eco-hydraulic in Northwest Arid Region of China Xi’an University of TechnologyXi’anShaanxi 710048China Heilongjiang River Fisheries Research Institute Chinese Academy of Fishery SciencesHarbinHeilongjiang 150076China Gansu Fisheries Research Institute LanzhouGansu 730030China Hunan Fisheries Science Institute ChangshaHunan 410153China Yunnan Institute of Fishery Sciences Research KunmingYunnan 650111China

The genus Silurus,an important group of catfish,exhibits heterogeneous distribution in Eurasian freshwater *** group includes economically important and endangered species,thereby attracting considerable scientific *** this interest,the lack of a comprehensive phylogenetic framework impedes our understanding of the mechanisms underlying the extensive diversity found within this ***,we analyzed 89 newly sequenced and 20 previously published mitochondrial genomes(mitogenomes)from 13 morphological species to reconstruct the phylogenetic relationships,biogeographic history,and species diversity of *** phylogenetic reconstructions identified eight clades,supported by both maximum-likelihood and Bayesian ***-based species delimitation analyses yielded multiple molecular operational taxonomic units(MOTUs)in several taxa,including the Silurus asotus complex(four MOTUs)and Silurus microdorsalis(two MOTUs),suggesting that species diversity is underestimated in the genus.A reconstructed time-calibrated tree of Silurus species provided an age estimate of the most recent common ancestor of approximately 37.61 million years ago(Ma),with divergences among clades within the genus occurring between 11.56 Ma and 29.44 Ma,and divergences among MOTUs within species occurring between 3.71 Ma and 11.56 *** reconstructions suggested that the ancestral area for the genus likely encompassed China and the Korean Peninsula,with multiple inferred dispersal events to Europe and Central and Western Asia between 21.78 Ma and 26.67 Ma and to Japan between 2.51 Ma and 18.42 *** factors such as the Eocene-Oligocene extinction event,onset and intensification of the monsoon system,and glacial cycles associated with sea-level fluctuations have likely played significant roles in shaping the evolutionary history of the genus Silurus.

关键词： Maximum likelihood Bayesian inferences Ancestral area estimation Cryptic diversity Dispersal pathways Mitogenomes Sea levels

一种基于CMOS的宽带抗阻塞射频接收机设计

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太赫兹科学与电子信息学报 2024年第8期22卷 878页

作者：杨静致翁振豪高志强王琮哈尔滨工业大学航天学院黑龙江哈尔滨150001 哈尔滨工业大学电子与信息工程学院黑龙江哈尔滨150001

针对在多频段、多模式无线通信应用中传统射频接收机频段单一、集成度低的问题,基于N通道滤波技术与接收机集成化技术,提出一种基于互补金属氧化物半导体(CMOS)的宽带抗阻塞射频接收机。该接收机集成N通道混频器与基带滤波器,在65 nm C... 详细信息

针对在多频段、多模式无线通信应用中传统射频接收机频段单一、集成度低的问题,基于N通道滤波技术与接收机集成化技术,提出一种基于互补金属氧化物半导体(CMOS)的宽带抗阻塞射频接收机。该接收机集成N通道混频器与基带滤波器,在65 nm CMOS工艺下进行版图测试。仿真实验结果表明,该接收机在5 MHz的基带带宽外提供超过60 dB的带外阻塞抑制,频率调谐范围0.25~2.5 GHz;前置内嵌巴伦的低噪声放大器,使接收机转换增益达到46 dB,同时降低整体噪声系数至3.1~4 dB;实现了24.5 dBm的带外三阶交调截取点(IIP3),功耗为26 mW。

关键词：射频接收机N通道滤波器低噪声放大器混频器抗阻塞

热解法在氮化硼基底上沉积碳膜衰减器的工艺研究

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真空科学与技术学报 2023年第10期43卷 897-901页

作者：张彬高闿阅高志强程飞高学强张志强济钢防务技术有限公司济南250100 山东微波电真空技术有限公司济南250100 枣庄学院枣庄277106

螺旋线行波管是一种应用较为广泛的宽频带、高增益行波功率放大器件。衰减器是提高管子性能稳定性的关键部件之一。它不仅可以吸收在管子输入、输出端及切断端传输介质的变化引起的反射波,抑制反射波和向前波叠加引起的自激振荡;而且,... 详细信息

螺旋线行波管是一种应用较为广泛的宽频带、高增益行波功率放大器件。衰减器是提高管子性能稳定性的关键部件之一。它不仅可以吸收在管子输入、输出端及切断端传输介质的变化引起的反射波,抑制反射波和向前波叠加引起的自激振荡;而且,可以减小传输电路在输入、输出端及切断端产生的阻抗不匹配的影响,扩宽行波管有效传播的频带宽度;同时可以避免陶瓷杆的上的电荷积累造成的放电或电弧。文章通过低压真空热解正庚烷,调整加热场热子温度、加热时间、腔室气压、气体流动等因素,制备出了满足螺旋线行波管设计要求的碳膜衰减器。主要阐述和验证了碳膜衰减器制备过程中从选材到制备过程中的工艺要求及各因素对碳膜衰减器阻值的影响,为螺旋线行波管碳膜衰减器的制备提供了实验依据。

关键词：螺旋线行波管碳膜衰减器热解法氮化硼

Thermal and mechanical behavior of casting copper alloy wheel during wheel and belt continuous casting process

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China Foundry 2024年第1期21卷 82-90页

作者： Kun gao Yan Peng School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina

To investigate the thermal and mechanical behavior of casting wheel,a two-dimensional thermoelastic-plastic finite element model was used to predict the temperature,stress and distortion distribution of the casting wheel during the wheel and belt continuous casting *** effects of grinding thickness and casting speed on the thermal and mechanical behaviors of the center of the hot face of the casting wheel were discussed in *** each rotation,the casting wheel passes through four different spray *** results show that the temperature distribution of the casting wheel in different spray zones is similar,the temperature of the hot face is the highest and the temperature reaches the peak in the spray zoneⅢ.The stress and distortion depend on the temperature distribution,and the maximum stress and distortion of the hot face are 358.2 MPa and 1.82 mm,*** temperature at the center of the hot face decreases with increasing grinding thickness and increases with increasing casting speed.

关键词： casting wheel finite element model grinding thickness casting speed hot face spray zones

On the core entropy of Newton maps

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Science China Mathematics 2024年第1期67卷 77-128页

作者： Yan gao Department of Mathematics Shenzhen UniversityShenzhen 518060China

In this paper,we define the core entropy for postcritically-finite Newton maps and study its continuity within this *** show that the entropy function is not continuous in this family,which is different from the polyn... 详细信息

关键词： core entropy extended Newton graph critical marking polynomial Newton map

Durable poly(binaphthyl-co-p-terphenyl piperidinium)-based anion exchange membranes with dual side chains

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Journal of Energy Chemistry 2024年第2期89卷 324-335,I0008页

作者： Weiting gao Xuelang gao Qiugen Zhang Aimei Zhu Qinglin Liu Department of Chemical&Biochemical Engineering Fujian Provincial Key Laboratory of Theoretical and Computational ChemistryThe College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005FujianChina Department of Chemistry Pohang University of Science and Technology(POSTECH)Pohang 790-784South Korea

Building well-developed ion-conductive highways is highly desirable for anion exchange membranes(AEMs).Grafting side chain is a highly effective approach for constructing a well-defined phaseseparated morphological structure and forming unblocked ion pathways in AEMs for fast ion *** of side chains can further enhance phase separation due to the superhydrophobic nature of fluorine ***,their electronic effect on the alkaline stability of side chains and membranes is rarely ***,fluorine-containing and fluorine-free side chains are introduced into the polyaromatic backbone in proper configuration to investigate the impact of the fluorine terminal group on the stability of the side chains and membrane *** poly(binaphthyl-co-p-terphenyl piperidinium)AEM(QBNp TP)has the highest molecular weight and most dimensional stability due to its favorable backbone arrangement among ortho-and meta-terphenyl based ***,by introducing both a fluorinated piperidinium side chain and a hexane chain into the p-terphenyl-based backbone,the prepared AEM(QBNp TP-QFC)presents an enhanced conductivity(150.6 m S cm^(-1))and a constrained swelling at 80℃.The electronic effect of fluorinated side chains is contemplated by experiments and *** results demonstrate that the presence of strong electro-withdrawing fluorine groups weakens the electronic cloud of adjacent C atoms,increasing OH^(-)attack on the C atom and improving the stability of piperidinium *** QBNp TP-QFC possesses a robust alkaline stability at 80℃(95.3%conductivity retention after testing in 2 M Na OH for 2160 h).An excellent peak power density of 1.44 W cm^(-2)and a remarkable durability at 80℃(4.5%voltage loss after 100 h)can be observed.

关键词： Anion exchange membranes Backbone structure Fluorinated side chain Alkaline stability