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Optoelectronics Letters 2007年第3期3卷 169-172页

作者： WANG Cai-feng LI qing-shan ZHANG Li-chun LV Lei qi Hong-xia College of Physics and Engineering Qufu Normal University Qufu 273165 China Ludong University Yantai 264025 China

ZnS films were deposited on porous Si(PS) substrates with different porosities by pulsed laser deposition. The photolumi-nescence spectra of the samples were measured to study the effect of substrate porosity on luminescence properties of ZnS/porous Si composites. After deposition of ZnS films,the red photoluminescence peak of porous Si shows a slight blueshift compared with as-prepared porous Si samples. With an increase of the porosity,a green emission at about 550 nm was observed which may be ascribed to the defect-center luminescence of ZnS films,and the photoluminescence of ZnS/porous Si composites is very close to white light. Good crystal structures of the samples were observed by x-ray diffraction,showing that ZnS films were grown in preferred orientation. Due to the roughness of porous Si surface,some cracks appear in ZnS films,which could be seen from scanning electron microscope images.

关键词：衬底孔隙度 ZnS薄膜光致发光多孔硅衬底脉冲激光沉积

The molecular characterization of maize B chromosome specific AFLPs

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Cell Research 2002年第1期12卷 63-68页

作者： ZHONG xia qi, Hui ZENG, Xiu LAN LI, CHENG BIN CHEN, WEN qiN SONG, RUI YANG CHEN The College of Life Sciences, Nankai University, Tianjin 300071, China The College of Life Sciences Nankai University Tianjin China

The origin and evolution of B chromosomes could be explained by the specific DNA sequence on them. But the specific sequences known were quite limited. To investigate maize B chromosome sqicific DNA sequeces, maize genomes with and without B chromosomes were analyzed by AFLP. Only 5 markers were found specific to genomes with B chromosomes among about 2000 AFLP markers. Southern hybridization and sequence analysis revealed that only the sequence of M8-2D was a B chromosome specific sequence. This sequence contained the telomeric repeat unit AGGGTTT conserved in plant chromosome telomeres. In addition, the sequence of M8-2D shared low homology to clones from maize chromosome 4 centromere as well. M8-2D were localized to B chromosome centrorneric and telomeric regions.

关键词： Maize B chromosome AFLP FISH.

Measurement of Plasma Rotation Velocities with Limiter Biasing on the CT-6B Tokamak

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Chinese Physics Letters 1997年第8期14卷 597-600页

作者： ZHOU Bao-suo YANG Xuan-zong WANG Long FENG Chun-hua JIANG Di-ming qi xia-zhi Center for Space Science and Applied Research Chinese Academy of SciencesBeijing 100080 Institute of Physics Chinese Academy of SciencesBeijing 100080

H-mode-like phenomenon is observed with positive limiter biasing on the CT-6B *** rotation of plasma in the boundary region is slowed and even changed its direction with positive bias,effect of positive bias on the to... 详细信息

关键词： Tokamak rotation Plasma

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电控液晶光阀中的指向矢分布特性

光子学报 2014年第4期43卷 155-158页

作者：祁建霞西安邮电大学理学院西安710121

液晶分子具有介电和光学各向异性,在外电场作用下,液晶指向矢将会重新分布,具有高效的光学相位调制能力.本文从实验和理论角度对电控液晶光阀的光学调制特性进行了研究,结果表明:光阀阈值电压约为4V,且当外加电压高于阈值电压时,液晶光... 详细信息

液晶分子具有介电和光学各向异性,在外电场作用下,液晶指向矢将会重新分布,具有高效的光学相位调制能力.本文从实验和理论角度对电控液晶光阀的光学调制特性进行了研究,结果表明:光阀阈值电压约为4V,且当外加电压高于阈值电压时,液晶光阀的透射强度随外加电压表现出非周期性特性.根据液晶连续体弹性理论,对电场作用下液晶光阀的指向矢分布特性进行数值分析,分析结果表明液晶光阀对透射光强的非周期调制特性取决于液晶体系的偏转状态,为研究液晶的偏振光调制特性提供理论依据及实验基础.

关键词：液晶光学各向异性偏振电光特性数值计算

The value of gastroenterultrasound developer in diagnosis of the stomach tumor

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The Chinese-German Journal of Clinical Oncology 2008年第7期7卷 398-399页

作者： qi Xu Jianguo xia Department of Ultrasonography The Puai Hospital of Wuhan Wuhan 430033 China

Objective: To study the value of gastroenterultrasound developer in diagnosis of the stomach tumor. Methods: 38 patients who diagnosed as stomach tumor by gastroscopy were chosen, and their images before and after by using gastroenterultrasound developer were compared. Results: The difference between the detectable rate of stomach tumor before and after by using gastroenterultrasound developer was significant (P < 0.01). Conclusion: Gastroenterultrasound developer has a high diagnostic value in diagnosis of the stomach tumor.

关键词： gastroenterultrasound developer stomach tumor ultrasonic examination

添加水合物促进二氧化碳水合物生成的实验研究

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高校化学工程学报 2010年第5期24卷 842-846页

作者：祁影霞张华上海理工大学能源与动力学院上海200093

水合物法分离、封存二氧化碳,是减少温室气体排放的有效方法之一。今在专门设计的水合物形成实验装置上,研究了二氧化碳水合物初始生成相平衡条件及其影响因素。分别在纯水中加入2.5%、6%和12.5%体积比的水合物晶块进行水合物的生成实验... 详细信息

水合物法分离、封存二氧化碳,是减少温室气体排放的有效方法之一。今在专门设计的水合物形成实验装置上,研究了二氧化碳水合物初始生成相平衡条件及其影响因素。分别在纯水中加入2.5%、6%和12.5%体积比的水合物晶块进行水合物的生成实验,发现当加入量为6%体积比以上时,不但可以缩短水合物初始形成时所需要的诱导时间,还可以大大降低过冷度,最低可使其在接近相平衡点的状态下生成水合物。而当加入量为2.5%体积比时,与未加入时相同,没有降低过冷度或缩短诱导时间的作用。本研究结果可用于缩短水合物生成时的诱导时间和降低装置的耐压极限,并提示为防止天然气管道中的水合物的重复堵塞问题,应尽可能彻底清除管道中的水合物残余物。

关键词：二氧化碳水合物过冷度合成水合物添加物

无产阶级办报传统的追根溯源——《新莱茵报》出版史考证

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出版发行研究 2019年第10期 97-103页

作者：夏琪中国人民大学新闻学院

《新莱茵报》是马克思直接创办的唯一一份大型政治性日报,也是第一个马克思主义政党--共产主义者同盟的机关报。办报期间,马克思和恩格斯不仅审阅每期报纸的所有内容,还撰写过400余篇文章,同编辑部成员直接参与德国科隆和其他地区的工... 详细信息

《新莱茵报》是马克思直接创办的唯一一份大型政治性日报,也是第一个马克思主义政党--共产主义者同盟的机关报。办报期间,马克思和恩格斯不仅审阅每期报纸的所有内容,还撰写过400余篇文章,同编辑部成员直接参与德国科隆和其他地区的工人运动,这是马克思主义新闻出版史上的光辉一页。本文依据全套原版报纸和其他最新材料,详细考证《新莱茵报》的出版、发行、停刊以及后期传播。文章梳理出报纸正刊、号外和增刊的具体数字,考证了科隆地区每个季度的具体发行量,论证停刊的主要原因,以及报纸内容在后世的传播。马克思开创的无产阶级党报传统必须深入研究,才可能加以弘扬,成为当今中国共产党的新闻舆论工作的指导。

关键词：马克思主义新闻观《新莱茵报》欧洲革命马克思出版史

Detection of arboviruses in Culicoides(Diptera:Ceratopogonidae)collected from animal farms in the border areas of Yunnan Province,China

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Journal of Integrative Agriculture 2021年第9期20卷 2491-2501页

作者： DI Di LI Chen-xi LI Zong-jie WANG Xin xia qi-qi Mona SHARMA LI Bei-bei LIU Ke SHAO Dong-hua qiU Ya-feng Soe-Soe WAI YANG Shi-biao WEI Jian-chao MA Zhi-yong Shanghai Veterinary Research Institute Chinese Academy of Agricultural SciencesShanghai 200241P.R.China Yunnan Tropical and Subtropical Animal Virus Diseases Laboratory Yunnan Animal Science and Veterinary InstituteKunming 650224P.R.China Department of Veterinary Public Health University of Veterinary ScienceYezin 15013Myanmar

Biting midges of the genus Culicoides(order Diptera,family Ceratopogonidae)are potential biological vectors for the transmission of certain arboviruses among humans,livestock,and wild *** study collected a total of 405 Culicoides individuals from seven animal farms located in five counties in the border areas of Yunnan Province,China,and examined the Culicoides species composition and the major arboviruses carried by the Culicoides *** collected Culicoides were classified into seven species with variable abundances:Culicoides arakawae(5.43%,22/405),Culicoides homotomus(1.23%,5/405),Culicoides obsoletus(19.75%,80/405),Culicoides orientalis(17.28%,70/405),Culicoides oxystoma(29.38%,119/405),Culicoides peregrinus(5.68%,23/405),and Culicoides nipponensis(21.23%,86/405).Among the seven species,*** and *** were distributed in all the five counties with abundances of 13.33–44.87%and 10.00–46.83%,respectively,suggesting that these were the dominant species of Culicoides widespread on animal farms in the border *** was used to detect major arboviruses in the collected Culicoides specimens,including bluetongue virus(BTV),Japanese encephalitis virus,Dengue virus,Zika virus,African swine fever virus,and African horse sickness *** the tested viruses,only BTV serotype 1 was tested positive in *** specimens collected from a buffalo *** oxystoma was the dominant species on animal farms in the sampled areas,but it has not previously been documented as positive for BTV in *** current results thus suggest that *** could be an important vector for BTV transmission in these border areas,which,however,needs to be confirmed by further comprehensive ***,the present study provides the first profile of Culicoides species on animal farms in the China,Vietnam,and Myanmar border areas,establishes the prevalence of arboviruses carried by these Culicoides species,and suggests the vector potential of C.

关键词： biting midge Culicoides bluetongue virus arbovirus arthropod vector

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

The Design and Implementation of a Very Fast Experimental Pipelining Computer

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Journal of Computer Science and Technology 1988年第1期3卷 1-6页

作者：林琦夏培肃 Institute of Computing Technology Academia Sinica

The high speed potential of *** can be exploited by shortening the pipeline clock *** there are some factors which dominate the shortening,the design of an experimental computeremploys the principle of maximum time difference at the system level to determine the clock period and theintegrated consideration of architecture,logic design and engineering layout to achieve a system clock periodof 9.8 ns using conventional ECL chips of 2ns gate *** multiplier in this model,which is constructedwith 0.7 ns gate delay chips,can work at a cloek period of 5.5 ns.

关键词： The Design and Implementation of a Very Fast Experimental Pipelining Computer line