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Chinese Chemical Letters 2002年第10期13卷 945-948页

作者： Wei ZHANG Jian Li HUA jin Gui qin Department of Chemistry Wuhan UniversityWuhan 430072

This paper reports the synthesis and the nonlinear optical property of a series of new chromophores which contain furan ring as the only conjugation bridge for the first time. They are characterized by UV-VIS, FT-IR, H-1 NMR, MS and elemental analysis. Their dipole moment and the first-order molecular hyperpolarizability (beta) are calculated and compared with those or the analogues containing either benzene or thiophene as file conjugation bridge.

关键词： 5-diethylamino-2-furaldehyde chromophores nonlinear optical materials organic synthesis the first-order molecular hyperpolarizability (b)

Eosinophilic gastroenteritis with ascites and hepatic dysfunction

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World Journal of Gastroenterology 2007年第8期13卷 1303-1305页

作者： Hai-Bo Zhou jin-Ming Chen qin Du Department of Gastroenterology Second Affiliated Hospital of Zhejiang University Hangzhou 310009 Zhejiang Province China

Eosinophilic gastroenteritis is a rare gastrointestinal disorder with eosinophilic infiltration of the gastrointestinal wall and various gastrointestinal dysfunctions. Diagnosis requires a high index of suspicion and exclusion of various disorders that are associated with peripheral eosinophilia. We report a case of eosinophilic gastroenteritis, which had features of the predominant subserosal type presenting with ascites and hepatic dysfunction, and which responded to a course of low-dose steroid.

关键词： Ascites Eosinophilia Gastroenteritis

A Novel Route to Synthesize Nano-crystalline Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O(3-δ) Perovskite Oxide at High Temperature

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Chinese Chemical Letters 2006年第10期17卷 1353-1356页

作者： Wei ZHOU Zong Ping SHAO Wan qin jin Key Laboratory of Materials-Oriented Chemical Engineering of Ministry of Education of China College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing 210009

It is normally difficult to prepare nano-sized Ba0.5Sr0.5Co0.8Fe0.2O3-δ（BSCF） oxide at high temperature due to its high surface activity. The complexing process, which has successfully applied in the synthesis of nano Sm0.15Ce0.85I1.925 with crystallite size down to 5 nml, just resulted in a coarse BSCF with crystaUite size of 41.9 nm at 900℃. We applied a novel process by simply modifying the solid precursor from the complexing process with concentrated nitric acid treatment. The obtained BSCF powder had a crystaUite size of -25 nm even calcined at 1000℃. The small crystaUite size is extremely promising to enhance the electrochemical performance of cathode for solid oxide fuel cell dramatically.

关键词： Nano-crystallite perovskite solid oxide fuel cells.

A Corrected Solid Boundary Treatment Method for Smoothed Particle Hydrodynamics

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China Ocean Engineering 2017年第2期31卷 238-247页

作者： CHEN Yun-sai ZHENG Xing jin Shan-qin DUAN Wen-yang College of Shipbuilding Engineering Harbin Engineering University Harbin 150001 China Department of Technology National Deep Sea Center Qingdao 266061 China

Smoothed Particle Hydrodynamics method （SPFI） has a good adaptability for simulating of free surface flow problems. However, there are some shortcomings of SPH which are still in open discussion. This paper presents a corrected solid boundary handling method for weakly compressible SPH. This improved method is very helpful for numerical stability and pressure distribution. Compared with other solid boundary handling methods, this corrected method is simpler for virtual ghost particle interpolation and the ghost particle evaluation relationship is clearer. Several numerical tests are given, like dam breaking, solitary wave impact and sloshing tank waves. The results show that the corrected solid boundary processing method can recover the spurious oscillations of pressure distribution when simulating the problems with complex geometry boundary.

关键词： SPH particle arrangement boundary treatment solitary wave impact sloshing wave

Detection of Serine Octamer by Desorption Electrospray Ionization Mass Spectrometry in Resultant Mixture of Aspartic Acid Exposed to Sunshine Under Natural Conditions

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Chemical Research in Chinese Universities 2007年第6期23卷 650-653页

作者： CHEN Huan-wen LI Ming jin Wei jin qin-han ZHENG Jian College of Chemistry Jilin Province Research Center of Engineering and Technology for Spectral Instruments Jilin University Changchun 130021 P. R. China Applied Chemistry Department East China University of Technology Fuzhou 344000 P. R. China College of Information Science and Engineering Zhejiang University Hangzhou 310027 P. R. China Beijing Physical and Chemical Analysis Center Beijing 100089 P. R. China

Serine, one of the nonessential amino acids, is of principal interest because of its capability to form magic-number ionic clusters, which provide a remarkable preference for homochirality. With L-aspartic acid as the precursor, this study provides experimental evidence for serine formation in weak acidified aqueous solutions in the presence of iron, with exposure to sunlight, which simulates the natural conditions of the prebiotic aqueous environment. The resultant mixture is directly analyzed via desorption electrospray ionization mass spectrometry（ DESI-MS）, without any sample preseparation. The serine monomer is successfully detected as protonated molecules, giving a peak at m/z 106, which is confirmed by the MS/MS fragments. Protonated serine octamer（ m/z 841 ） is also observed with significant abundance in the MS spectra and is confirmed by the MS/MS data, which shows the formation of the serine octamer by a synthesized serine in the resultant mixture. It is also found that the serine octamer yielded equivalent abundance in the DESI mass spectra in a wide pH range（pH = 1-5 ）, and that existence of ferrous salt and sunshine are essential for the conversion of aspartic acid to serine in the acidic water solution.

关键词： Serine octamer Aspartic acid Photocatalysis DESI Mass spectrometry

Influence of fabric anisotropy on seismic responses of foundations

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Journal of Rock Mechanics and Geotechnical Engineering 2015年第2期7卷 147-154页

作者： jin qin Xiangwu Zeng Haiyan Ming Department of Civil Engineering Case Western Reserve University Department of Civil Engineering Shenzhen University

Earthquakes, as one of the well-known natural disasters, are highly destructive and *** failure due to liquefaction induced by earthquakes can cause casualties as well as significantdamage to the building itself. Fabric anisotropy of soil grains is considered to be an important factor indynamic soil response based on previous researches and laboratory tests. However, the limited availabilityof real physical data makes it less persuasive. In this study, a shake table installed on ageotechnical centrifuge is used to provide the designed seismic motions, and therefore, to simulate therealistic earthquake motion to foundations. Important parameters in the responses such as acceleration,excess pore pressure and deformation are evaluated to investigate the influence. Implications for designare also discussed. 2015 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved.

关键词： Soil mechanics Angular sand Centrifuge modeling Fabric anisotropy Seismic response

高速铁路日常客运量的EMD-Informer组合预测方法

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铁道学报 2024年第2期46卷 1-11页

作者：秦进胡冉毛成辉小虎徐光明中南大学交通运输工程学院湖南长沙410075

铁路客流需求的科学预测是进行运输组织方案决策的重要依据。以高速铁路历史客票数据为基础,结合经验模态分解(empirical mode decomposition,EMD)与机器深度学习中的注意力机制,提出高速铁路日客流量的EMD-Informer组合预测方法。首先... 详细信息

铁路客流需求的科学预测是进行运输组织方案决策的重要依据。以高速铁路历史客票数据为基础,结合经验模态分解(empirical mode decomposition,EMD)与机器深度学习中的注意力机制,提出高速铁路日客流量的EMD-Informer组合预测方法。首先采用EMD方法分解高速铁路客流量序列,获得具有周期特征和线路客流内在特征的模态分量,再利用Informer模型分别训练和预测各模态分解分量,并通过多头注意力机制高效挖掘客流数据内在规律和捕捉数据序列中的关键特征,在此基础上重组各分量预测值,从而得到高速铁路日常客流的整体高精度预测值。同时,根据结合问题特征的大量实验,明确可供实际运用参考的超参数设置规则。基于京沪高速铁路全线的实例计算分析表明,相对对比预测方法,EMD-Informer组合预测方法在高速铁路客流的单步预测及超前预测上均具有明显更小的预测误差。

关键词：高速铁路客运量预测经验模态分解注意力机制 Informer模型

Lane-changing decision rule with the difference of traffic flow's variation in multi-lane highway for connected and autonomous vehicles

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Transportation Safety and Environment 2023年第3期5卷 112-121页

作者： Chuanyao Li Dexin Huang Tao Wang jin qin School of Traffic and Transportation Engineering Central South UniversityChangsha 410075HunanChina School of Automotive and Transportation Engineering Hefei University of TechnologyHefei 230009AnhuiChina

Drivers are not far-sighted when they execute lane-changing *** address this issue,this study proposes a rule to improve vehicles'lane-changing decisions with accurate information of surrounding vehicles(*** headway)-More specifically,connected and autonomous vehicles(CAVs)change lanes in advance if they find severer flow reducing in the lanes,while CAVs should maintain the car-following state if the variations of traffc flow in all lanes have a similar *** ilustrate the idea,this study frst calibrates two classic car-following models and a lane-changing model,and then conducts numerical simulations to illustrate the short-sighted decision of *** study incorporates the idea into a lane-changing decision rule by changing the lane-changing model's pa-rameter,and conducts numerical tests to evaluate the effectiveness of the lane-changing decision rule in a multi-lane highway with a *** results of this study indicate that the new lane-changing decision rule can substantially improve the throughput of the traffic flow,especially when the inflow exceeds the remaining capacity of the *** lane-changing rule and results can bring insights into the control of CAVs,as well as the driver assistance system in connected vehicles.

关键词： lane-changing manoeuvre decision rule connected and autonomous vehicle(CAV)

The impacts of climate change and human activities on grassland productivity in qinghai Province, China

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Frontiers of Earth Science 2014年第1期8卷 93-103页

作者： Fang YIN Xiangzheng DENG qin jin Yongwei YUAN Chunhong ZHAO Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Center for Chinese Agricultural Policy Chinese Academy of Sciences Beijing 100101 China School of Mathematics and Physics China University of Geosciences Wuhan 430074 China Faculty of Resource and Environmental Science Hubei University Wuhan 430062 China

qinghai Province, which is the source of three major rivers （i.e., Yangtze River, Yellow River and Lancang River） in East Asia, has experienced severe grassland degradation in past decades. The aim of this work was to analyze the impacts of climate change and human activities on grassland ecosystem at different spatial and temporal scales. For this purpose, the regression and residual analysis were used based on the data from remote sensing data and meteorological stations. The results show that the effect of climate change was much greater in the areas exhibiting vigorous vegetation growth. The grassland degradation was strongly correlated with the climate factors in the study area except Haixi Prefecture. Temporal and spatial heterogeneity in the quality of grassland were also detected, which was probably mainly because of the effects of human activities. In the 1980s, human activities and grassland vegetation growth were in equilibrium, which means the influence of human activities was in balance with that of climate change. However, in the 1990s, significant grassland degradation linked to human activities was observed, primarily in the Three-River Headwaters Region. Since the 21st century, this adverse trend continued in the qinghai Lake area and near the northern provincial boundaries, opposite to what were observed in the eastern part of study. These results are consistent with the currently status of grassland degradation in qinghai Piovince, which could serve as a basis for the local grassland management and restoration programs.

关键词： climate change human activities grassland degradation spatial distribution residual analysis

基于神经架构搜索及特征组合的便携式雷达个体识别方法

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航天电子对抗 2024年第2期40卷 1-4页

作者：茆旋宇王欢王佩秦晋中国航天科工集团8511研究所江苏南京210007

电磁环境日趋复杂、雷达辐射源体制愈发多样,面向现代电子对抗需求的辐射源个体识别任务充满严峻挑战,特别是针对便携式雷达目标,个体识别模型性能会随着环境、参数变化、调制方式变换等因素出现显著下降。针对上述问题,提出了一种基于... 详细信息

电磁环境日趋复杂、雷达辐射源体制愈发多样,面向现代电子对抗需求的辐射源个体识别任务充满严峻挑战,特别是针对便携式雷达目标,个体识别模型性能会随着环境、参数变化、调制方式变换等因素出现显著下降。针对上述问题,提出了一种基于神经架构搜索及特征组合的个体识别方法,利用神经架构搜索自适应组建深度神经网络模型,对原始信号、不同特征之间的组合进行结构化调整,提高模型面对便携式雷达信号时的识别性能。

关键词：神经架构搜索个体识别便携式雷达