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Geochemical characteristics of aromatic hydrocarbons in crude oils from the Linnan Subsag, Shandong Province, China

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Chinese Journal Of Geochemistry 2011年第1期30卷 132-137页

作者： CHANG Xiangchun HAN Zuozhen SHANG Xiaofei yan chengpeng Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Scienceand Technology Qingdao 266510 China

Abundant aromatic fractions were detected in oils from the Linnan subsag, including aphthalenes, phenanthrenes, triaromatic steroids, biphenyl, fluorenes, dibenzothiophenes, dibenzofuranes, as well as some typical higher plant-sourced compounds, such as pyrene, benzopyrene, fluoranthene, chryaene, benzofluoranthrene, perylene and cadalene. Occurrences of biomarkers indicate that oils from the Linnan subsag are typical terrestrially genetic oils. Developed in the depositional environment is a strong reduction condition typical of brackish-saline lake. Thermal evolution has entered into the mature-high mature stage.

关键词：碳氢化合物临南洼陷地球化学特征芳香族山东省原油中国成熟阶段

Geochemistry and origin of deep-seated cracked gas on the northern slope of the Dongying Sag, Shandong Province

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Chinese Journal Of Geochemistry 2011年第3期30卷 353-358页

作者： CHANG Xiangchun HAN Zuozhen XU Youde SHANG Xiaofei yan chengpeng Shandong provincial Key Laboratory of Deporattonal Mmeraltzatlon and Sedtmentary Mmerals Shandong Umverslty of Science and Technology Qingdao 266510 China Geological Scientific Research Instttute of Shengli Oilfield Company SINOPEC Dongying 257001 China

Deep-seated cracked gas exploration was achieved great breakthrough in Es4L of the Minfeng area on the northern slope of the Dongying Sag. Carbon isotopic and molecular compositions studies revealed the characteristics of wet gas and a normal trend of carbon isotopic composition. Empirical cutoff points of δ13C2 and δ13C3 and light hydrocarbon compositions distinguished the cracking gas as sapropelic gas. Variations in i/nC5, i/nC4 and δ13C2 fur-ther confirmed that the gas was cracked from residual kerogen. Source characteristics indicated that the gas was de-rived from mature-highly mature source rocks of Es4 with kerogen type II being dominant mixed with some oil-cracking gas. Burial history modeling indicated that there were two hydrocarbon charging periods in Es4L reser-voirs. The first period refers to the Guantao-Minghuazhen stage dominated by oil charging, while the second period refers to the Minghuazhen stage and has been dominated by cracked gas charging till now.

关键词：干酪根裂解气东营凹陷北部地球化学特征山东省碳同位素组成起源干酪根类型分子组成

First-principle screening of corrosion resistant solutes(Al,Zn,Y,Ce,and Mn)in Mg alloys for Integrated Computational Materials Engineering guided stainless Mg design

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Materials Genome Engineering Advances 2024年第1期2卷 80-96页

作者： Zhihao yang Junsheng Wang Chi Zhang Shuo Wang chengpeng Xue Guangyuan Tian Hui Su Chengming yan Zhifei yan Yingchun Tian School of Materials Science and Engineering Beijing Institute of TechnologyBeijingChina Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijingChina School of Materials Science and Engineering Shenyang University of TechnologyShenyangChina China North Industries Group No.52 Research InstituteBaotouInner MongoliaChina

Mg alloy suffers from its poor corrosion resistance as a result of anodic dissolution of Mg and hydrogen evolution reaction(HER)in humid *** this study,the effects of alloying elements(Al,Zn,Y,Ce,and Mn)on both processes in Mg alloys have been quantitatively *** first-principle calculations,we first obtained the substitution energies of alloying elements to compare their segregation preference,and then analyzed the influence of solutes at different layers on the stability and hydrogen adsorption properties of Mg(0001)surface by calculating the formation enthalpy,surface energy,vacancy formation energy,work function,Bader charge,deformation charge density,and adsorption free energy of H *** has been found that,on the one hand,the interior Mn solute atoms reduce the dissolution of Mg atoms and the transfer of electrons,consequently slowing down the anodic dissolution *** another hand,the Mn,Y,and Ce elements on the surface inhibit the cathodic HER process by elevating the absolute value of hydrogen adsorption free energy,as a result of those solutes effectively controlling H adsorption behavior on Mg(0001)*** contrast,all five elements dissolved inside the Mg grain do not show significant effects on the H adsorption behavior.

关键词： corrosion DFT first-principle hydrogen evolution reaction Mg alloys stainless Mg

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城市轨道交通车辆减重节能技术

城市轨道交通研究 2024年第2期27卷 242-246页

作者：曹成鹏闫俊材王兴佳北京城市轨道交通咨询有限公司北京100068 金华市轨道交通集团有限公司金华321015 河北雄安轨道快线有限责任公司保定071799

[目的]由于城市轨道交通(以下简称“城轨”)车辆新增的全自动驾驶技术、高冗余性技术等均在不同程度上增加了车载设备的数量,导致城轨车辆的质量越来越大,且由于城轨车辆的总体运量较大,导致其总体耗电量也维持在一个较高的水平。因此,... 详细信息

[目的]由于城市轨道交通(以下简称“城轨”)车辆新增的全自动驾驶技术、高冗余性技术等均在不同程度上增加了车载设备的数量,导致城轨车辆的质量越来越大,且由于城轨车辆的总体运量较大,导致其总体耗电量也维持在一个较高的水平。因此,需对城轨车辆的减重节能技术进行研究。[方法]分别介绍了车体、牵引系统及辅助电源系统、转向架及制动系统、空调系统及车门系统、车钩及贯通道、车辆内装及客室设备的减重措施;分别介绍了牵引系统及辅助电源系统、空调系统和照明系统的节能措施。[结果及结论]可采用的减重措施主要有:车体采用全铝结构;牵引系统采用永磁同步电动机;辅助电源系统采用高频辅助逆变器;充电机采用高频软开关设计;转向架采用轻量化设计;制动系统采用模块化设计;内装及客室设备采用新型材料。可采用的节能措施主要有:牵引系统采用永磁同步电动机;辅助电源系统采用高频拓扑结构;空调系统采用变频技术;照明系统采用OLED(有机发光二极管)光源。应用所介绍的减重及节能措施,基本能够达到车辆整体减重10%以上、节能10%以上的目标。

关键词：城市轨道交通车辆减重节能

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基于模型阶数选择准则的稳健杂波边缘检测方法

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电子与信息学报 2024年第7期46卷 2703-2711页

作者：金禹希吴敏郝程鹏殷超然吴永清闫林杰中国科学院声学研究所北京100190 中国科学院大学北京100049

在雷达目标自适应检测问题当中,辅助数据存在杂波边缘的情况将导致杂波协方差矩阵(CCM)的估计性能出现严重下降,极大地影响目标检测性能。为了解决这一问题,该文提出一种杂波边缘检测方法,能够对辅助数据中杂波边缘数量与位置进行自适... 详细信息

在雷达目标自适应检测问题当中,辅助数据存在杂波边缘的情况将导致杂波协方差矩阵(CCM)的估计性能出现严重下降,极大地影响目标检测性能。为了解决这一问题,该文提出一种杂波边缘检测方法,能够对辅助数据中杂波边缘数量与位置进行自适应判别。首先,假定辅助数据中存在杂波边缘,采用模型阶数选择算法和最大似然估计方法完成杂波参数估计,其中杂波边缘位置由循环搜索方法得到。之后将杂波参数估计结果应用到检测算法中,通过广义似然比检验方法来判断杂波边缘是否存在。此外为了进一步提升算法在小样本条件下的稳健性,引入CCM的特殊结构作为先验知识,将算法推广至CCM为斜对称、谱对称以及中心对称3种结构的情况。仿真及实测数据均表明该文所提算法能够高效地识别雷达辅助数据中的杂波边缘数量和位置,先验知识的引入更能进一步改善算法在辅助数据量较小时的性能。

关键词：自适应雷达检测杂波分类杂波边缘知识辅助

Unsymmetrical photochromic bithienylethene-bridge tetraphenylethene molecular switches:Synthesis,aggregation-induced emission and information storage

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Chinese Chemical Letters 2020年第2期31卷 361-364页

作者： Liangwei Ma chengpeng Li Qing yan Sheng Wang Wangen Miao Derong Cao School of Chemistry and Chemical Engineering Key Lab of Clean Energy Materials Chemistry of Guangdong Higher Education InstitutesLingnan Normal UniversityZhanjiang 524048China School of Chemistry and Chemical Engineering State Key Laboratory of Luminescent Materials and DevicesSouth China University of TechnologyGuangzhou 510641China

Aggregation-induced emission(AIE) active photochromic molecules have attracted growing attention for their versatile *** we designed and synthesized five newly unsymmetrical photochromic diarylethene(DAE) dyads(BTE1-5) by connecting tetraphenylethene(TPE) and aromatic substituent via bithienylethene(BTE) *** chemical structures of those compounds were identified by ^1H NMR,^(13)C NMR and *** absorption and emission of these dyads were investigated by UV-vis and fluore scence spectroscopy,*** results showed that all those compounds exhibited typically AIE or aggregation-induced emission enhancement(AIEE) ***,when an aggregationcaused quenching(ACQ) fluorophore(triphenylamine) was grafted to the molecule,connecting with TPE via BTE-bridge,the ACQ phenomenon was dissipated and converted to an AIE luminophore,and those compounds exhibited photochromism upon irradiation with alternative UV and visible *** solution or solid of those compounds showed distinctly fluorescence switching "ON" or "OFF" observation upon irradiation with alternative UV and visible *** is interesting that BTE1 could be applied in recording and rewritable information storage,and the cyclization quantum yields could be affected by substituent significantly.

关键词： Aggregation-induced emission Bithienylethene Photochromic Tetraphenylethene Information storage

Target localization and parameters estimation by sonar system with explosions as underwater sound sources

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Chinese Journal of Acoustics 2016年第4期35卷 416-430页

作者： yan Sheng WEI Xiaojun HAO chengpeng MA Hui yan Shefeng Institute of Acoustics Chinese Academy of Sciences

Underwater target localization and parameters(azimuth and range) estimation by the method of utilizing explosions as underwater sound sources are described in this *** narrow beam reverberation model of the target echo signal is researched to estimate the target azimuth in reverberation *** errors of target azimuth and range are studied and proved to approximately meet Gauss *** the variance formula of target range error is *** experiments are applied to research the target range error and its standard deviation,and a series of measures to improve the estimation accuracy of target range are *** is confirmed by the data processing results of simulations and lake experiments that the proposed method can accurately locate underwater target at a long distance on the condition of a certain underwater explosion range error.

关键词： Target localization and parameters estimation by sonar system with explosions as underwater sound sources

Ultra-high strength yet superplasticity in a hetero-grain-sized nanocrystalline Au nanowire

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Journal of Materials Science & Technology 2022年第6期101卷 95-106页

作者： Libo Fu Deli Kong chengpeng yang Jiao Teng yan Lu Yizhong Guo Guo yang Xin yan Pan Liu Mingwei Chen Ze Zhang Lihua Wang Xiaodong Han Beijing Key Lab of Microstructure and Properties of Advanced Materials Beijing University of TechnologyBeijing 100124China Department of Material Physics and Chemistry University of Science and Technology BeijingBeijing 100083China School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Department of Materials Science and Engineering Johns Hopkins UniversityBaltimoreMD 21218United States School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027China

Nanocrystalline metals often display a high strength up to the gigapascal level,yet they suffer from poor *** studies have shown that the development of hetero-sized grains can efficiently overcome the strength-ductility trade-off of nanocrystalline ***,whether this strategy can lead to the fabrication of nanocrystalline nanowires exhibiting both high strength and superplasticity is unclear,similar to the atomistic deformation *** this paper,we show that ultra-small nanocrystalline Au nanowires comprising grains in both the Hall–Petch and inverse Hall–Petch grain-size regions can exhibit extremely high uniform elongation(236%)and high strength(2.34 gigapascals)at room *** situ atomic-scale observations revealed that the plastic deformation underwent two *** the first stage,the super-elongation ability originated from the intergrain plasticity of small grains via mechanisms such as grain boundary migration and grain *** intergrain plasticity caused the grains in the heterogeneous-structured nanowires to grow very *** the second stage,the superelongation ability originated from intragrain plasticity accompanied by the diffusion of surface *** results show that the hetero-grain-sized nanocrystalline nanowires,comprising grains with sizes both in the strongest Hall–Petch effect region and the inverse Hall–Petch effect region,were simultaneously ultrastrong and *** displayed neither a strength-ductility trade-off nor plastic instability.

关键词： In situ Mechanical property Metallic nanowires Transmission electron microscopy Plastic deformation

Robust guidance method with terminal impact angle constraint for autonomous underwater vehicle

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Chinese Journal of Acoustics 2016年第4期35卷 476-484页

作者： SI Changlong MA Hui HAO chengpeng yan Shefeng Institute of Acoustics Chinese Academy of Sciences

Based on robust control design method,a variable structure guidance method is proposed for autonomous underwater vehicle(AUV) during the guiding course with terminal impact angle *** the intercept geometry,a sliding mode controller is proposed for controlling the hne of sight angle rate and the impact angle,based on the principle which controls the line of sight angle rate to approach zero and the terminal angle to approach the expected value more quickly as the distance *** results show that,with the application of the proposed method,small miss distance is achieved and the expected impact angle is *** addition,the system is robust to the target maneuvering.

关键词： AUV Robust guidance method with terminal impact angle constraint for autonomous underwater vehicle