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Compound-specific hydrogen isotopes of long-chain n-alkanes extracted from topsoil under a grassland ecosystem in northern China

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Science China Earth Sciences 2011年第12期54卷 1902-1911页

作者： RAO ZhiGuo zhu ZhaoYu jia GuoDong ZHANG Xiao WANG SuPing Key Laboratory of Western China＇s Environment Systems （Ministry of Education） Lanzhou University Lanzhou 730000 China Key Laboratory of Marginal Sea Geology Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

To investigate characteristics of H isotope variation in long-chain n-alkanes (δDn-alkanes) from higher plants in surface soils under a single ecosystem, 12 samples from a basalt regolith were randomly collected from Damaping in Wanquan County of Zhangjiakou in North China. Molecular distribution and C (δ13Cn-alkanes) and H isotopes of long-chain n-alkanes, as well as C isotopes of TOC (δ13CTOC), were analyzed. Both δ13CTOC and δ13Cn-alkanes values from four representative dominant long-chain n-alkanes (n-C27, n-C29, n-C31, n-C33) derived from terrestrial higher plants show minor variations among the 12 samples, indicating the major contributor is from local grasses with a uniform C3 photosynthetic pathway. In contrast, variations in δDn-alkanes values of the four long-chain n-alkanes are relatively large, with the more abundant homologs generally showing more negative δDn-alkanes values and less variation. However, variation of <30‰ among weighted averaged δDn-alkanes values of the four long-chain n-alkanes is not only less than that among δDn-alkanes values for different modern terrestrial C3 grasses from the specific locations, but also less than the literature values of δDn-alkanes of long-chain n-alkanes for single species over different seasons. Thus, because the sources of long-chain n-alkanes in surface soils and sediments are similarly from multiple individual plants, our results are significant in confirming that paleoclimatic, paleoenvironmental and paleohydrological information can be interpreted more accurately from δDn-alkanes values of long-chain n-alkanes from sediments, particularly terrestrial sediments with organic matter derived from in-situ plants.

关键词：长链正构烷烃草原生态系统氢同位素中国北方地表土壤烃化合物高等植物提取

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三维流场的虚拟现实技术开发与教学应用

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力学与实践 2024年第3期46卷 643-648页

作者：贾永霞张钧铎吴辰禹朱虹鑫刘泽华陆晨阳黄伟希清华大学航天航空学院北京100084 清华大学力学国家级实验教学示范中心北京100084

开发了一种动态展示三维精细流场结构的虚拟现实系统。该系统包括:流场生成模块,用于通过数值模拟计算目标场景的瞬时流场,并进行可视化,得到目标场景的三维流场模型;存储模块,用于存储目标场景的三维流场模型;显示模块,根据按键指令调... 详细信息

开发了一种动态展示三维精细流场结构的虚拟现实系统。该系统包括:流场生成模块,用于通过数值模拟计算目标场景的瞬时流场,并进行可视化,得到目标场景的三维流场模型;存储模块,用于存储目标场景的三维流场模型;显示模块,根据按键指令调用并播放三维流场模型。通过虚拟现实技术实现多种模型的三维瞬时流场动态展示,实现了在流体力学教育与研究领域还原复杂流场中三维结构的功能,极大地激发了学生的求知欲与探索精神。

关键词：虚拟现实三维流场涡结构

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Estimation of the Aerosol Radiative Effect over the Tibetan Plateau Based on the Latest CALIPSO Product

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Journal of Meteorological Research 2018年第5期32卷 707-722页

作者： Rui jia Yuzhi LIU Shan HUA qingzhe zhu Tianbin SHAO Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric SciencesLanzhou University

Based on the CALIPSO （Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation） Version 4.10 products released on 8 November 2016, the Level 2 （L2） aerosol product over the Tibetan Plateau （TP） is evaluated and the aerosol radiative effect is also estimated in this study. As there are still some missing aerosol data points in the day-time CALIPSO Version 4.10 L2 product, this study re-calculated the aerosol extinction coefficient to explore the aer-osol radiative effect over the TP based on the CALIPSO Level 1 （L1） and CloudSat 2B-CLDCLASS-LIDAR products. The energy budget estimation obtained by using the AODs （aerosol optical depths） from calculated aerosol extinction coefficient as an input to a radiative transfer model shows better agreement with the Earth＇s Radiant En- ergy System （CERES） and CloudSat 2B-FLXHR-LIDAR observations than that with the input of AODs from aero- sol extinction coefficient from CALIPSO Version 4.10 L2 product. The radiative effect and heating rate of aerosols over the TP are further simulated by using the calculated aerosol extinction coefficient. The dust aerosols may heat the atmosphere by retaining the energy in the layer. The instantaneous heating rate can be as high as 5.5 K day^-1 de-pending on the density of the dust layers. Overall, the dust aerosols significantly affect the radiative energy budget and thermodynamic structure of the air over the TP, mainly by altering the shortwave radiation budget. The signific-ant influence of dust aerosols over the TP on the radiation budget may have important implications for investigating the atmospheric circulation and future regional and global climate.

关键词： aerosol radiative effect Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) Version 4.10 product Tibetan Plateau

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Enhancing room-temperature thermoelectric performance of n-type Bi_(2)Te_(3)-based alloys via sulfur alloying

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Rare Metals 2021年第3期40卷 513-520页

作者： Feng Liu Ye-Hao Wu qi Zhang Tie-Jun zhu Xin-Bing Zhao State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China

Bismuth-telluride-based alloys are the best thermoelectric materials used in commercial solid-state refrigeration near room ***,for n-type polycrystalline alloys,their thermoelectric figure of merit(zT) values at room temperature are often less than1.0,due to the high electron concentration originating from the donor-like effect induced by the mechanical deformation ***,carrier concentration for better performance near room temperature was optimized through manipulating intrinsic point defects by sulfur *** alloying significantly decreases antisite defects concentration and suppresses donor-like effect,resulting in optimized carrier concentration and reduced electronic thermal *** hot deformation process was also applied to improve carrier mobility due to the enhanced *** a result,a high zT value of 1 at 300 K and peak zT value of 1.1 at 350 K were obtained for the twice hot-deformed Bi_(2) Te_(2.7)Se_(0.21)S_(0.09) sample,which verifies sulfur alloying is an effective method to improve thermoelectric performance of n-type polycrystalline Bi2 Te3-based alloys near room temperature.

关键词： Bismuth telluride Thermoelectric Point defect Sulfur alloying Hot deformation

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Elaiophylin triggers paraptosis and preferentially kills ovarian cancer drug-resistant cells by inducing MAPK hyperactivation

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Signal Transduction and Targeted Therapy 2022年第10期7卷 3925-3939页

作者： Guan-Nan Li Xue-jiao Zhao Zhen Wang Meng-Shi Luo Shen-Nan Shi Dan-Mei Yan Hua-Yi Li jia-Hao Liu Yang Yang jia-Hong Tan Ze-Yu Zhang Ru-qi Chen Hui-Ling Lai Xiao-Yuan Huang jian-Feng Zhou Ding Ma Yong Fang qing-Lei Gao Cancer Biology Research Center(Key Laboratory of the Ministry of Education) Tongji HospitalTongji Medical CollegeHuazhong University of Science and Technology430030 WuhanHubeiChina National Clinical Research Center for Obstetrics and Gynecology Department of Gynecological OncologyTongji HospitalTongji Medical CollegeHuazhong University of Science and Technology430030 WuhanHubeiChina Department of Hematology Tongji HospitalTongji Medical CollegeHuazhong University of Science and Technology430030 WuhanHubeiChina Department of Gynecology the Sixth Affiliated HospitalSun Yat-Sen University510000 GuangzhouGuangdongChina

Finely tuned mitogen-activated protein kinase(MAPK)signaling is important for cancer cell *** that push cells out of the MAPK fitness zone result in cell ***,in a screen of the North China Pharmaceutical Group Corporation’s pure compound library of microbial origin,we identified elaiophylin as an autophagy ***,we demonstrated a new role for elaiophylin in inducing excessive endoplasmic reticulum(ER)stress,ER-derived cytoplasmic vacuolization,and consequent paraptosis by hyperactivating the MAPK pathway in multiple cancer ***-wide CRISPR/Cas9 knockout library screening identified SHP2,an upstream intermediary of the MAPK pathway,as a critical target in elaiophylin-induced *** cellular thermal shift assay(CETSA)and surface plasmon resonance(SPR)assay further confirmed the direct binding between the SHP2 and *** of the SHP2/SOS1/MAPK pathway through SHP2 knockdown or pharmacological inhibitors distinctly attenuated elaiophylin-induced paraptosis and autophagy ***,elaiophylin markedly increased the alreadyelevated MAPK levels and preferentially killed drug-resistant cells with enhanced basal MAPK *** overcame drug resistance by triggering paraptosis in multiple tumor-bearing mouse models resistant to platinum,taxane,or PARPi,suggesting that elaiophylin might offer a reasonable therapeutic strategy for refractory ovarian cancer.

关键词： cancer activation elevated

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柳州市不同产区麻竹笋品质分析

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广西林业科学 2024年第1期53卷 87-93页

作者：贾冬冬梁绍煜熊建文潘慧玲朱秀芬崔娜徐振国广西壮族自治区林业科学研究院广西优良用材林资源培育重点实验室广西南宁530002 广西大学林学院广西南宁530004 柳州市林业技术推广站广西柳州545000 柳州工学院食品与化学工程学院广西柳州545616 柳州市螺蛳粉植物源性配料研究重点实验室广西柳州545616

为揭示柳州市不同产区麻竹(Dendrocalamuslatiflorus)笋品质差异,以柳州螺蛳粉酸笋原材料认定基地的麻竹笋为研究对象,测定麻竹笋外观品质、营养品质和食味品质,比较分析各产区麻竹笋品质差异。结果表明,不同产区竹笋外观品质差异显著;... 详细信息

为揭示柳州市不同产区麻竹(Dendrocalamuslatiflorus)笋品质差异,以柳州螺蛳粉酸笋原材料认定基地的麻竹笋为研究对象,测定麻竹笋外观品质、营养品质和食味品质,比较分析各产区麻竹笋品质差异。结果表明,不同产区竹笋外观品质差异显著;柳北、柳城县-1产区竹笋基径、长度和质量均显著高于其他产区,可食率均较高;柳北产区竹笋外观品质最好。不同产区竹笋营养品质差异显著;柳城县-2产区竹笋蛋白质、淀粉、总糖、维生素C和氨基酸含量均较高,营养品质最好。不同产区竹笋食味品质差异显著;柳城县-1产区竹笋纤维素和单宁含量均最低,草酸含量较低,食味品质最好。不同产区竹笋品质综合得分指数表现为柳城县-1>柳北>柳城县-2>柳南>鱼峰。

关键词：外观品质营养品质食味品质麻竹

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猪圆环病毒2型疫苗及其效力评价方法比较研究

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中国兽药杂志 2024年第1期58卷 87-94页

作者：徐嫄彭国瑞徐小艾吴睿智赵启祖朱元源李翠王团结邹兴启李琰刘业兵中国兽医药品监察所北京100081

为探索对不同猪圆环病毒2型(Porcine circovirus type2,PCV2)疫苗产品进行统一质量评价的可行性,对国内该类疫苗产品及其现有效力评价方法进行了归纳和比较研究。结果发现,目前猪圆环病毒2型疫苗类产品种类有25个,且疫苗毒株数量多达10... 详细信息

为探索对不同猪圆环病毒2型(Porcine circovirus type2,PCV2)疫苗产品进行统一质量评价的可行性,对国内该类疫苗产品及其现有效力评价方法进行了归纳和比较研究。结果发现,目前猪圆环病毒2型疫苗类产品种类有25个,且疫苗毒株数量多达10余个,效力检验方法包括传统的免疫攻毒法、血清学方法和多种不同的替代方法,但尚没有统一的效力评价体系。本研究可为进一步完善PCV2疫苗效力评价方法、统一评价疫苗效力、提高产品质量提供参考。

关键词：猪圆环病毒2型疫苗效力评价方法

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Electrochemical machining of burn-resistant Ti40 alloy

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Chinese Journal of Aeronautics 2015年第4期28卷 1263-1272页

作者： Xu Zhengyang Liu jia zhu Dong Qu Ningsong Wu Xiaolong Chen Xuezhen College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics

This study investigates the feasibility of using electrochemical machining（ECM） to produce critical aeroengine components from a new burn-resistant titanium alloy（Ti40）, thereby reducing costs and improving efficiency relative to conventional mechanical *** this, it is found that an aqueous mix of sodium chloride and potassium bromide provides the optimal electrolyte and that the surface quality of the Ti40 workpiece is improved by using a pulsed current of1 k Hz rather than a direct ***, the quality of cavities produced by ECM and the overall material removal rate are determined to be dependent on a combination of operating voltage, electrolyte inlet pressure, cathode feeding rate and electrolyte *** optimizing these parameters, a surface roughness of 0.371 lm has been achieved in conjunction with a specific removal rate of more than 3.1 mm3/A？min.

关键词： Burn resistant Electrochemical machining Material removal:Surface roughness:Titanium alloys

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Spintronic devices for neuromorphic computing

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Science China(Physics,Mechanics & Astronomy) 2020年第7期63卷 124-126页

作者： YaJun Zhang qi Zheng XiaoRui zhu Zhe Yuan Ke Xia Center for Advanced Quantum Studies and Department of Physics Beijing Normal UniversityBejing 100875China Peng Cheng Laboratory Center for Quantum ComputingShenzhen 518005China Shenzhen Institute for Quantum Science and Engineering and Department of Physics Southern University of Science and TechnologyShenzhen 518055China

In the past decades,significant progress has been achieved in artificial intelligence,which is now widely applied in image recognition,big data analysis,unmanned vehicle control and other cognitive tasks[1].These applications nevertheless are highly energy consuming partly because of the mismatch between the neural-network-computing-based software im-plementation and the von Neumann architecture of present *** promising solution is developing neuro-morphic chips without the so-called von Neumann bottle-neck,which are suitable for performing the desired computation based on artificial neural networks(ANNs).

关键词： consuming desired computing

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基于数据采样方法的城市道路自由流行程时间估计

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浙江大学学报（工学版） 2022年第6期56卷 1241-1248页

作者：俞怡曾佳棋王殿海浙江大学建筑工程学院浙江杭州310058

基于交通波模型,提出利用车牌识别数据估计城市道路自由流行程时间.无需额外架设检测器或现场测算,所提方法具备准确性、科学性、实用性的特点.基于车辆均匀到达的假设,将行程时间分为自由流行程时间和延误,建立信号影响下的路段行程时... 详细信息

基于交通波模型,提出利用车牌识别数据估计城市道路自由流行程时间.无需额外架设检测器或现场测算,所提方法具备准确性、科学性、实用性的特点.基于车辆均匀到达的假设,将行程时间分为自由流行程时间和延误,建立信号影响下的路段行程时间分布函数.针对现实环境中车流非均匀到达的特点,提出数据重采样方法生成符合均匀流假设的行程时间数据;拟合行程时间分布函数以获得路段自由流行程时间.在杭州市多个路段的数据验证结果表明,重采样后的行程时间数据较好地拟合了行程时间分布模型,估得的自由流行程时间准确且具备理论支撑.

关键词：自由流行程时间行程时间分布数据重采样城市道路

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