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Responsivity and noise characteristics of AlGaN/GaN-HEMTterahertz detectors at elevated temperatures

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chinese Physics B 2019年第5期28卷 355-360页

作者： zhi-Feng Tian Peng Xu Yao Yu Jian-Dong Sun Wei Feng Qing-Feng ding Zhan-Wei Meng Xiang Li {2.-Hua Cai Zhong-Xin Zheng Xin-Xing Li Lin {2. Hua Qin Yun-Fei Sun Key Laboratory of Nano Devices and Applications Suzhou Institute of Nano-tech and Nano-bionics Chinese Academy of Sciences School of Physical Science and technology Shanghai Technology University Shanghai institute of Ceramics Chinese Academy of Sciences University of chinese academy of sciences Nano Science and technology institute University of Science and Technology of China School of Nano technology and Nano Bionics University of Science and Technology of China beijing Huahang Radio Measurement & Research institute College of Electronic and Information Engineering Suzhou University of Sciences and Technology

The responsivity and the noise of a detector determine the sensitivity. Thermal energy usually affects both the responsivity and the noise spectral density. In this work, the noise characteristics and responsivity of an antenna-coupled AlGaN/GaN high-electron-mobility-transistor(HEMT) terahertz detector are evaluated at temperatures elevated from 300 K to 473 K. Noise spectrum measurement and a simultaneous measurement of the source–drain conductance and the terahertz photocurrent allow for detailed analysis of the electrical characteristics, the photoresponse, and the noise behavior. The responsivity is reduced from 59 mA/W to 11 mA/W by increasing the detector temperature from 300 K to 473 K. However,the noise spectral density maintains rather constantly around 1–2.pA/Hz^(1/2. at temperatures below 448 K, above which the noise spectrum abruptly shifts from Johnson-noise type into flicker-noise type and the noise density is increased up to one order of magnitude. The noise-equivalent power(NEP) is increased from 2. pW/Hz^(1/2. at 300 K to 60 pW/Hz^(1/2. at 448 K mainly due to the reduction in mobility. Above 448 K, the NEP is increased up to 1000 pW/Hz^(1/2. due to the strongly enhanced noise. The sensitivity can be recovered by cooling the detector back to room temperature.

关键词： terahertz detection gallium nitride noise spectrum responsivity

Extraction of tight binding parameters from in-situ ARPES on the continuously doped surface of cuprates

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Science china(Physics,Mechanics & Astronomy) 2018年第12期61卷 25-29页

作者： YiGui Zhong YiMeng Chen JianYu Guan jin Zhao zhiCheng Rao CenYao Tang HaiJiang Liu YuJie Sun Hong {2. beijing National Laboratory for Condensed Matter Physics and institute of Physics Chinese Academy of SciencesBeijing 100190China School of Physics University of Chinese Academy of SciencesBeijing 100190China Collaborative Innovation Center of Quantum Matter Beijing 100190China

Recently we developed a technique of ozone/vacuum annealing to continuously change the doping level of the surface of Bi_2.r_2.aCu_2._(8+)and measured a nearly whole superconducting dome on one surface by in-situ angle-resolved photoemission spectroscopy [arXiv: 1805.06450]. Here we study the evolution of the electronic structures of Bi_2.r_2.aCu_2._(8+)xusing this technique together with tight binding fits. The tight binding parameters are extracted to study their evolution with doping.

关键词： cuprates electronic structures doping evolution tight binding ARPES

A significant quantitative trait locus on chromosome Z and its impact on egg production traits in seven maternal lines of meat-type chicken

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Journal of Animal Science and Biotechnology 2023年第1期14卷 47-59页

作者： Jiqiang ding Fan Ying Qinghe Li Gaomeng Zhang jin Zhang Ranran Liu Maiqing Zheng Jie Wen Guiping Zhao institute of Animal sciences Chinese Academy of Agricultural SciencesBeijingChina. MiLe Xinguang Agricultural and Animal Industrials Corporation MiLeChina.

Background:Egg production is economically important in the meat-type chicken *** better understand the molecular genetic mechanism of egg production in meat-type chicken,genetic parameter estimation,genome-wide association analyses combined with meta-analyses,Bayesian analyses,and selective sweep analyses were performed to screen single nucleotide polymorphisms(SNPs)and other genetic loci that were significantly associated with egg number traits in 11,2.9 chickens from seven material ***:Yellow-feathered meat-type chickens laid 115 eggs at 43 weeks of age and white-feathered chickens laid 143 eggs at 60 weeks of age,with heritability ranging from 0.034–*** on meta-analyses and selective sweep analyses,one region(10.81–13.05 Mb)on chromosome Z was associated with egg number in all *** analyses using the W2.line was also associated with the same region,and 2. SNPs were identified that significantly affected estimation of breeding value of egg *** 2. SNPs were identified as having a significant effect on the egg number EBV in 3194 birds in line *** are 36 genes in the region,with glial cell derived neurotrophic factor,DAB adaptor protein 2.protein kinase AMP-activated catalytic subunit alpha 1,NAD kinase 2.mitochondrial,WD repeat domain 70,leukemia inhibitory factor receptor alpha,complement C6,and complement C7 identified as being potentially affecting to egg *** addition,three SNPs(rs318154184,rs13769886,and rs31332.646)associated with egg number were located on or near the prolactin receptor ***:Our study used genomic information from different chicken lines and populations to identify a genomic region(spanning 2.2. Mb)associated with egg *** genes and 2. SNPs were identified as the most likely candidate genes and variations for egg *** results contribute to the identification of candidate genes and variants for egg traits in poultry.

关键词： Candidate gene Egg production Genome-wide association study Meat-type chicken Selective sweep analysis

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河南董寨再引入朱鹮种群的巢址分布特征

动物学杂志 2024年第1期59卷 11-18页

作者：黄华王科黄治学蔡德靖刘进法朱家贵席学博王代平河南信阳罗山县董寨国家级自然保护区管理局罗山464236 中国科学院动物研究所动物生态与保护生物学院重点实验室北京100101

为了解再引入朱鹮(Nipponia nippon)种群的分布与扩张情况,本研究对董寨再引入朱鹮野外种群的繁殖巢址进行了调查研究。在2.14到2.2.年间,共调查统计了84个野化放飞朱鹮及其后代的繁殖巢址,使用圆形分布法分析了巢址与放飞点的相对方位... 详细信息

为了解再引入朱鹮(Nipponia nippon)种群的分布与扩张情况,本研究对董寨再引入朱鹮野外种群的繁殖巢址进行了调查研究。在2.14到2.2.年间,共调查统计了84个野化放飞朱鹮及其后代的繁殖巢址,使用圆形分布法分析了巢址与放飞点的相对方位和集中程度,并根据全部巢址的空间分布,使用固定核空间方法计算得到巢区(95%巢址所在区域)与核心巢区(50%巢址所在区域)的分布范围和面积。将巢址图层、土地覆盖图层以及数字高程模型叠加,观察朱鹮巢址选择的生境偏好,并使用单样本t检验判断了巢址平均海拔与巢区海拔间的差异。结果显示,繁殖巢址与放飞点平均距离(平均值±标准差)(12.82.14.11)km(n=84),平均方位角(平均值±标准差)为(138.99±82.44)°(瑞利检验:Z=10.60,P3 km^(2.和549.66 km^(2.。巢址平均海拔(平均值±标准差)(103±43)m,显著低于巢区内平均海拔(t=﹣5.48,df=83,P<0.01)。巢址的分布主要位于水稻田和森林的交界区域。逐年繁殖区域分布图显示,繁殖区域基本朝向西北-东南方向扩张,与圆形分布分析结果一致。本研究描述了董寨再引入朱鹮种群繁殖巢址的分布特征与扩张趋势,可以为野外朱鹮潜在繁殖地和栖息地的保护提供参考,优化保护工作中的人力物力资源配置。

关键词：朱鹮再引入繁殖巢址分布区河南董寨

Record of hydrothermal activity in the Yuhuang hydrothermal field and its implications for the Southwest Indian Ridge:evidence from sulfide chronology

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Acta Oceanologica Sinica 2023年第11期42卷 59-68页

作者： Weifang Yang Chunhui Tao Shili Liao jin Liang Wei Li Teng ding Ágata Alveirinho Dias Xuefeng Wang Lisheng Wang Key Laboratory of Submarine Geosciences Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China School of Oceanography Shanghai Jiaotong UniversityShanghai 200030China School of Marine Science and Engineering Nanjing Normal UniversityNanjing 210023China institute of Science and Environment University of Saint JosephMacao 999078China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

The Yuhuang hydrothermal field(YHF)is located between the Indomed and Gallieni fracture zones near the top of the off-axis slope on the south rift wall of Segment 2. on the ultraslow Southwest Indian Ridge(SWIR).Previous studies have shown that sulfides in the YHF formed during different mineralization episodes and the YHF has the greatest potential for the formation of large-scale seafloor massive sulfide ***,the sulfide chronology and hydrothermal activity of the YHF remain poorly *** this study,mineralogical analyses and 2.0Th/U dating were *** activity may start about(35.9±2.3)ka from the southwest part of the YHF and may cease about(708±81)a ago from the northeast part of the *** 74 nonzero chronological data from hydrothermal sulfide samples provide the first quantitative characterization of the spatial and temporal history along the *** activity in the SWIR has been relatively active over the past2. *** contrast,between 40 ka and 100 ka,hydrothermal activity was relatively infrequently and short in *** maximum activity occurred at 15–11 ka,9–7 ka,6–0.2.*** was a slight positive correlation between the maximal age and estimated surface area or estimated *** minimum mass accumulation rate of YHF is about 2.8 t/a,which is higher than most HFs related to ultramafic *** ultraslow spreading SWIR has the greatest potential to form large-scale seafloor massive sulfides(SMS)*** results of this study provide new insights into the metallogenic mechanism of hydrothermal sulfides along ultraslow-spreading ridges.

关键词： Southwest Indian Ridge seafloor massive sulfides 2.0Th/U dating hydrothermal activity mass accumulation

Models and measurements of seven years of evapotranspiration on a high elevation site on the Central Tibetan Plateau

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Journal of Mountain Science 2020年第12期17卷 3039-3053页

作者： WANG Li-hui HE Xiao-bo Jakob FSTEINER ZHANG Dong-wei WU jin-kui WANG Shao-yong ding Yong-jian State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of chinese academy of sciences Beijing 100049China Department of Physical Geography Utrecht UniversityUtrecht 3584CBNetherlands

Evapotrantaspiration is a crucial part of the hydrological cycle but few ground observatories for the Tibetan Plateau *** this study,we present lysimeter measurements from the growing season during seven years at a remote field location on the Tibetan *** measurements show rates between 2.5 and 3 mm·d-1 during the warmer months from June to August,dropping to 2.to 2.5 mm·d-1 in *** results in a total volume of evapotranspiration of approximately 300 mm·yr-1 for the months from June to *** inter-daily variability is however large,and comparison to meteorological variables suggest that this is largely driven by radiation and *** for a single season from a nearby flux tower allows us to compare the two common measurement methods for evapotranspiration in the field,showing an overall good agreement between the *** also tested commonly applied models used to estimate evapotranspiration rates,namely the FAO-PenmanMonteith(PM) and the Priestly-Taylor(PT) model,which both make use of radiation data as well as the simpler Hargreaves-Samani(HS) and Rohwer(R)models which only need air temperature and wind speed as *** most data intensive model(PM)has the lowest root mean square error(RMSE)(1.36 mm·d-1) and the mean bias error(MBE)(-0.05 mm·d-1) and reproduces the daily variability generally *** much simpler HS model performs slightly worse(1.38 and 0.35 mm·d-1),but fails to reproduce the variability,due to its lack of information of local radiation and humidity *** results are in line with large scale estimates of evapotranspiration for the cold and arid region,provide a first long time series of in-situ measurements from a high elevation site and suggest that both the PM and HS models are appropriate when no direct measurements are available.

关键词： Evapotranspiration Alpine meadow FAO-Penman-Monteith Priestley-Taylor Hargreaves-Samani Rohwer Lysimeter

化学修饰的四环素对全氟异丁烯吸入性急性肺损伤的防治效果

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中国职业医学 2008年第1期35卷 7-9页

作者：赵建丁日高阮金秀张宪成孙晓红黄春倩杜先林军事医学科学院毒物药物研究所北京100850

目的观察化学修饰的四环素(米诺环素、多西环素)对全氟异丁烯(perfluoroisobutylene,PFIB)吸入性急性肺损伤的防治效果。方法采用小鼠动态吸入PFIB周身暴露染毒装置对实验小鼠进行染毒,观察了化学修饰的四环素(chemical modified tetrac... 详细信息

目的观察化学修饰的四环素(米诺环素、多西环素)对全氟异丁烯(perfluoroisobutylene,PFIB)吸入性急性肺损伤的防治效果。方法采用小鼠动态吸入PFIB周身暴露染毒装置对实验小鼠进行染毒,观察了化学修饰的四环素(chemical modified tetracyclines,CMTs)给药组与中毒对照组小鼠的肺系数以及支气管肺灌洗液(bronchoalveo larlavage fluid,BALF)中蛋白质含量的变化情况。结果米诺环素预防可以显著性地降低各项肺系数以及减少BALF中蛋白质的含量;多西环素预防可以显著性地减少BALF中蛋白质的含量,多西环素治疗可以显著性地降低湿肺体比和干肺体比。结论CMTs药物米诺环素对PFIB吸入性急性肺损伤具有预防作用,而多西环素对PFIB吸入性急性肺损伤具有较弱的预防和治疗作用。

关键词：米诺环素多西环素全氟异丁烯急性肺损伤

Melt-and air-processed selenium thin-film solar cells

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Science china Chemistry 2022年第11期65卷 2197-2204页

作者： Wenbo Lu Zongbao Li Mingjie Feng Hui-Juan Yan Bin Yan Liyan Hu Xing Zhang Shunchang Liu jin-Song Hu ding-Jiang Xue beijing National Laboratory for Molecular sciences(BNLMS) CAS Key Laboratory of Molecular Nanostructure and NanotechnologyInstitute of ChemistryChinese Academy of SciencesBeijing100190China School of Material and Chemical Engineering Tongren UniversityTongren 554300China National Engineering Research Center for Advanced Polymer Processing technology Zhengzhou UniversityZhengzhou 450002China University of chinese academy of sciences Beijing 100049China

Elemental selenium(Se), as the world’s first but long-neglected photovoltaic material, has regained great interest recently in tandem solar cells as top cells due to its wide bandgap(~1.8 eV), simple, non-toxic and earth-abundant composition, and intrinsic environmental stability. In particular, Se possesses the lowest melting point of 2.7 °C among the photovoltaic absorbers reported so far, endowing Se with a unique advantage of film fabrication by blade coating the Se melt on substrate. However, the poor wettability of Se melt on widely-used photovoltaic functional layers such as TiO_(2. limits its melt processing. Here we introduce a wettability-modification strategy that decreases the contact angle of Se melt on substrate and improves the wettability by appropriately enhancing the heating temperature of molten Se while avoiding Se volatilization. We further reveal the mechanism of the inherent air stability of Se that originates from the high activation energy of oxygen chemisorption on Se(3.2. eV). This enables the realization of compact Se films through melt-based blade coating in ambient air. The resulting Se solar cells exhibit an efficiency of 3.5%. Unencapsulated devices show no efficiency loss after 1,000 h of storage under ambient conditions.

关键词： selenium thin film photovoltaic melt processing

Two new species of Polyalthiopsis(Annonaceae) based on morphological characters and phylogenetic evidence,with a supplementary description of *** from china

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Plant Diversity 2023年第2期45卷 185-198页

作者： Bin Yang jin-Yue Li Rui-Jie Yang Hong-Bo ding Min Deng Chun-Fen Xiao Yun-Juan Zuo Yun-Hong Tan Southeast Asia Biodiversity Research institute Chinese Academy of Sciences&Center for Integrative ConservationXishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303YunnanChina The Key Laboratory of Rare and Endangered Forest Plants of National Forestry and Grassland Administration&The Key Laboratory for Silviculture and Forest Resources Development of Yunnan Province Yunnan Academy of Forestry and GrasslandKunming 650201YunnanChina College of Life Science University of Chinese Academy of SciencesHuairou DistrictBeijing 101408China School of Ecology and Environmental Science Yunnan UniversityKunming 650091YunnanChina Center for Gardening and Horticulture Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303YunnanChina

Two new species of Polyalthiopsis(Annonaceae),*** *** & Bin Yang from Guangxi and Yunnan Provinces and *** *** & Bin Yang from Yunnan Province,are described and *** is morphologically similar to *** in having narrowly elliptic-oblong,lemon to yellowish green petals,but differs by having obovoid monocarps,a higher number of leaf secondary veins,leaf blades usually widest above the middle,and a lower ratio of leaf blade length to *** is morphologically similar to *** in having axillary inflorescences,1-3(-4) flowers,elliptic leaves,and ellipticovate petals,but differs in the numbers of carpels per flower and ovules per *** molecular phylogenetic analysis using five plastid markers confirm that the two new species belong to the genus Polyalthiopsis and show clear interspecific divergences between *** and *** and between them and other species in the *** descriptions,colored photographs,and habitat and distribution data for the two new species are *** addition,the fruit morphology of *** is described for the first time,based on living *** distributions and a diagnostic key for all Polyalthiopsis species are also presented.

关键词： Annonaceae Morphology Polyalthia Polyalthiopsis Southeast Yunnan