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THz time-domain spectroscopy of amino acids

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Chinese Science Bulletin 2005年第15期50卷 1561-1565页

作者： WANG Weining YUE Weiwei yan haitao ZHANG Cunlin ZHAO Guozhong Department of Physics Capital Normal University. Beijing 100037China

The optical characteristics of four kinds of amino acids (tyrosine, arginine, histidine and glutamine) filled with nitrogen at room temperature were studied by THz time-domain spectroscopy (THz-TDS). Well-resolved absorption and refractive spectrums between 0.1 and 2.8 THz were obtained based on the physical model for extract-ing the optical parameters of materials in THz range. The results not only fill up the spectra gap of amino acids in far-infrared range, supply data for amino acid molecular identification and conformation analysis, but also demon-strate significantly potential to promote the research and application of biological materials in bio-chemical and medical fields by THz-TDS.

关键词：太赫时域光谱学氨基酸指纹光学参数

Efficacy evaluation and neurobiological mechanism of psychedelics based on looming model

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中国药理学与毒理学杂志 2023年第7期37卷 533-534页

作者： XIA Ke yan haitao SU Ruibin Beijing Key Laboratory of Neuropsychopharmacology State Key Laboratory of Toxicology and Medical Countermeasures Institute of Pharmacology and Toxicology Academy of Military Medical Sciences

OBJECTIVE To investigate the effect of psychedelics on innate fear behavior of mice in Looming model(LM) and its neurobiological mechanism. METHODS(1) Adult male C57BL/6J mice were randomly divided into saline group, DOM group, psilocybin group and mescaline group. The drugs of the corresponding groups were given ip injecction 5 min in advance and LM were used to test the effect of them on freezing time in shelter of mice.(2) The mice were performing ip given DOM or psilocybin following 5-HT2Areceptor antagonist M100907 ip30 min later involved looming experiments.(3) Quantified the expression of EGR1 protein in mouse brains by immunofluorescence staining, then use ibotenic acid(IBO) damaged the mouse brain regions based on the result above and performed looming experiments.(4) Specifically activate or inhibit CaMK Ⅱ, PV, VIP and SOM neurons of mice in saline or psilocybin groups respectively by chemical genetic methods and followed looming experiments. RESULTS(1) In LM, the freezing time in shelter of mice in DOM, psilocybin and mescaline groups was significantly shorter compared to the saline group(P<0.05), and the dose-effect curves of above psychedelics were U-shaped.(2) Compared with the vehicle +psilocybin/DOM groups, the freezing time in shelter of mice in M100907 + psilocybin/DOM groups was significantly prolonged(P<0.05), and there was no significant difference between the vehicle + saline group and the M100907 + psilocybin/DOM groups.(3) Psilocybin significantly increased the expression of EGR1 protein in prelimbic cortex(PrL) compared with saline, and the damage of PrL could effectively antagonized the effect of psilocybin shortening the freezing time in LM.(4) Chemicalgenetic specific inhibition of CaMK Ⅱ, PV or VIP neurons in PrL could effectively antagonize the effect of psilocybin in LM,while chemicalgenetic specific activation of CaMK Ⅱneurons could significantly shorten the freezing time of saline-treated mice. CONCLUSION Psychedelics have capability

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Understanding Bonding Nature of α-Keggin Polyoxometalates[XW_(12)O_(40)]^(n−)(X=Al,Si,P,S):A Generalized Superatomic Perspective

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Energy & Environmental Materials 2024年第6期7卷 176-183页

作者： Rui Li Yulei Shi Famin Yu Rui Wang haitao yan Boon K.Teo Zhigang Wang Department of Physics Capital Normal UniversityBeijing 100048China Key Laboratory of Material Simulation Methods&Software of Ministry of Education College of PhysicsJilin UniversityChangchun 130012China Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China State Key Laboratory for Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Institute of Theoretical Chemistry College of ChemistryJilin UniversityChangchun 130012China

α-Keggin polyoxometalates(POMs)[XW_(12)O_(40)]^(n−)(X=Al,Si,P,S)are widely used in batteries owing to their remarkable redox ***,the mechanism underlying the applications appears inconsistent with the widely accepted covalent bonding ***,first-principles calculations show that XW_(12)are core–shell structures composed of a shell and an XO_(4)^(n−)core,both are stabilized by covalent ***,owing to the presence of a substantial number of electrons in W_(12)O_(36)shell,the frontier molecular orbitals of XW_(12)are not only strongly delocalized but also exhibit superatomic properties with high-angular momentum electrons that do not conform to the Jellium *** analysis indicates that energetically high lying filled molecular orbitals(MOs)have reached unusually high-angular momentum characterized by quantum number K or higher,allowing for the accommodation of numerous *** attribute confers strong electron acceptor ability and redox activity to XW_(12).Moreover,electrons added to XW_(12)still occupy the K orbitals and will not cause rearrangement of the MOs,thereby maintaining the stability of these *** findings highlight the structure–activity relationship and provide a direction for tailor-made POMs with specific properties at atomic level.

关键词： first principles molecular orbital polyoxometalate redox activity superatom

Design Scheme of Electric Lifting Workbench for Maintenance of Aerometer in Observation Field

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Journal of Atmospheric Science Research 2019年第1期2卷 37-40页

作者： haitao yan Meteorological Bureau of Tai’an City Shandong ProvinceTai’an271000People’s Republic of China

The wind speed and wind direction meter of meteorological station is installed on the wind meter pole 10 meters high from the observation site, which also causes some difficulties for the maintenance of the wind speed and wind direction meter in the later period. Based on this situation, an electric lifting worktable (referred to as the electric lifting worktable) is specially designed for the maintenance of wind meters in meteorological observation sites. It can lift the maintenance personnel and equipment and tools to a height convenient for work, and then grasp the wind meter pole through the mechanical arm. It can be operated by a single person, thus getting rid of the traditional dimension by climbing the wind meter pole or releasing the wind meter pole. The present situation of repairing has the characteristics of saving manpower and easy operation, which is conducive to improving work efficiency and reducing work intensity. It also greatly guarantees the safety of maintenance personnel, and has good practicability and extensive popularization value.

关键词： Observation field Wind maintenance Electric lifting table Design scheme

Exploration and Research on Fault Maintenance System of New Generation Weather Radar

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Journal of Atmospheric Science Research 2019年第2期2卷 46-50页

作者： haitao yan Meteorological Bureau of Tai'an Tai’anShandong271000China

In order to improve the standardization, specialization, intelligence and timeliness of the new generation weather radar fault repair, the technical threshold of radar fault repair is greatly reduced, so that the general operators can carry out radar fault repair work. In order to achieve this goal, this paper designs a new generation weather radar fault repair system, which aims to solve two problems: one is to solve the causes and locations of the new generation weather radar faults which can be quickly and accurately detected and diagnosed[1];the other is to solve the problem that the grass-roots radar operational staff are inexperienced in maintenance and will not be repaired, and to provide visual through the maintenance system. Maintenance methods and steps with expert intelligence level [2], so that general radar operators can operate radar fault repair according to video steps, and have the technical level of maintenance experts, to achieve breakthroughs in technical difficulties of radar fault repair, to achieve both disease detection and treatment effect, to improve the efficiency of the use of new generation weather radar and to achieve modern technical equipment support. Chemistry plays an important role and significance.

关键词： New Generation Weather Radar Fault Maintenance System Exploration and Research

Magnetic response to atmospheric heavy metal pollution recorded by dust-loaded leaves in Shougang industrial area, western Beijing

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Chinese Science Bulletin 2008年第10期53卷 1555-1564页

作者： HU ShouYun DUAN XueMei SHEN MingJie U BLAHA W ROESLER yan haitao E APPEL V HOFFMANN State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sci- ences Nanjing 210008 China Graduate University of Chinese Academy of Sciences Beijing 100049 China epartment of Geography East China Normal University Shanghai 200062 China Institute for Geosciences University of Tubingen 72076 Tubingen Germany epartment of Geography Shanghai Normal-University Shanghai 200234 China

Fifty-five evergreen tree's leaves growing less than one year were collected from Shougang industrial area in western suburb of Beijing, including steel plants and its ambient residential areas, recreational parks and farmlands. Rock magnetic properties and heavy metal contents were studied. The results show that the magnetic properties of leaf samples are predominated by low-coercivity magnetite, and both the concentration and grain size of magnetite particles gradually decreased with the distance from the main pollution source increases. Moreover, there is a significant linear relationship between magnetic parameters (the low-field magnetic susceptibility, saturation isothermal remanent magnetization and anhysteretic remanent magnetization) and heavy metals contents (Fe, Pb, V, Cr and Zn) (0.73≤R≤ 0.88). Hence, the magnetic parameters of leaves can serve as a proxy for quick detecting of the recent atmospheric metallic pollution.

关键词：首钢集团大气重金属污染磁场参数环境保护

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数字散斑相关方法实现鼠标定位原理

光学学报 2008年第3期28卷 467-471页

作者：闫海涛王鸣南京师范大学物理科学与技术学院江苏省光电技术重点实验室江苏南京210097

在激光鼠标工作原理的基础上,利用数字散斑相关方法对激光鼠标的定位原理进行了研究。设计实验得到散斑场并用数码相机拍摄。用图像采集卡采集CCD扫描数散斑图像得到的图像,将图像数字化,分析数据得到了图像最优采样的像素单元和图像位... 详细信息

在激光鼠标工作原理的基础上,利用数字散斑相关方法对激光鼠标的定位原理进行了研究。设计实验得到散斑场并用数码相机拍摄。用图像采集卡采集CCD扫描数散斑图像得到的图像,将图像数字化,分析数据得到了图像最优采样的像素单元和图像位移两个参量。基于两个参量,实验采集散斑图像在一定的轨迹运动下的散斑场,用Matlab软件模拟,并比较分析了实验和模拟结果。结果表明,用数字散斑相关方法可以实现激光鼠标的定位功能,并且分辨力可达到1μm,远高于市场上激光鼠标30μm的分辨力。

关键词：成像光学数字散斑自相关激光鼠标定位

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Effect of grain boundary characteristic distribution on brittle cracking of ferritic stainless steel

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Baosteel Technical Research 2008年第1期2卷 9-12页

作者： Bi Hongyun yan haitao Li Xin Wang Weiming Technology Center for Stainless Steel Baosteel Research Institute Baoshan Iron ＆ Steel Co. Ltd. Shanghai 200431 China Key Laboratory for High Temperature Materials and Tests of Ministry of Education Shanghai Jiao Tong University Shanghai200030 China Stainless Steel Branch Baoshan Iron ＆ Steel Co. Ltd. Shanghai 200431 China

In order to better understand the relation between grain boundary characteristic distribution （GBCD） and the brittle cracking of ferritic stainless steel, the GBCD, impact test and bend test were investigated using scanning electron microscopy （SEM） and the electron backscatter diffraction （EBSD） technique. The results show that a crack occurs preferentially at high angle boundaries, and that low angle and low-∑ coincidence site lattice（CSL） boundaries can offer resistance to the propagation of cracks. It is suggested that an optimum GBCD, i.e. a high frequency of low angle or low-∑ CSL boundaries and discontinuous high angle boundaries network can offer the potential for decreasing the ductile-to-brittle transition temoerature （DBTT） of ferritic stainless steels.

关键词： grain boundary characteristic distribution ductile-to-brittle transition temperature ferritic stainless steel electron backscatter diffraction

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Monitoring Flue-Cured Tobacco Leaf Chlorophyll Content under Different Light Qualities by Hyperspectral Reflectance

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American Journal of Plant Sciences 2020年第8期11卷 1217-1234页

作者： Fangfang Jia Shuang Han Dong Chang haitao yan Yueqi Xu Wenna Song School of Life Sciences Shangqiu Normal University Shangqiu China School of Information Engineering Zhengzhou University Zhengzhou China Henan Pingdingshan Municipal Tobacco Company Pingdingshan China

Rapid assessment of foliar chlorophyll content in tobacco is critical for assessment of growth and precise management to improve quality and yield while minimizing adverse environmental impact. Our objective is to develop a precise agricultural practice predicting tobacco-leaf chlorophyll-a content. Reflectance experiments have been conducted on flue-cured tobacco over 3 consecutive years under different light quality. Leaf hyperspectral reflectance and chlorophyll-a content data have been collected at 15-day intervals from 30 days after transplant until harvesting. We identified the central band that is sensitive to tobacco-leaf chlorophyll-a content and the optimum wavelength combinations for establishing new spectral indices (simple ratio index, RVI;normalized difference vegetation index, NDVI;and simple difference vegetation index, DVI). We then established linear and BackPropagation (BP) neural network models to estimate chlorophyll-a content. The central bands for leaf chlorophyll-a content are concentrated in the visible range (410 - 680 nm) in combination with the shortwave infrared range (1900 - 2400 nm). The optimum spectral range for the spectral band combinations RVI, NDVI, and DVI are 440 and 470 nm, 440 and 470 nm, and 440 and 460 nm, respectively. The linear RVI, NDVI, and DVI models, SMLR model and the BP neural network model have respective R2