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Effect of CC Coherent Vibration on Relative Raman Scattering Cross Sections of All-trans β-Carotene

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Chemical Research in Chinese Universities 2010年第4期26卷 608-611页

作者： LI Zhan-long LI Dong-fei SUN Cheng-lin LI Zuo-wei ZHOU Qiang CAO jun-sheng GAO feng-li State Key Laboratory of Superhard Materials Jilin University Changchun 130012 P. R. China College of Physics Jilin Universty Changchun 130021 P. R. China Lab of Excited State Processes Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changchun 130033 P R. China State Key Laboratory of lntegrated Optoelectronics College of Electronic Science and Engineering Jilin University Changchun 130012 P R. China

We have determined the Raman scattering cross sections（RSCSs） of fl-carotene for C=C and C-C stretching modes, with the 1444 cm^-1 Raman band of cyclohexane as internal standard, in different solvents at low concentrations by measuring Raman intensity. The results show that RSCSs of β-carotene were 10^6-10^7 times larger than the general RSCSs, we analyzed that this enhancement was caused not only by the resonance Raman effect but also by nonlinear coherent CC vibration in aqueous β-carotene. Moreover, overtone and combinations of it were also observed and their intensities were 10%-20% of those of their fundamentals when β-carotene was dissolved in non-polar solvents, respectively.

关键词： Raman scattering cross section Electron-phonon coupling Coherent vibration

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储气库多周期运行井控参数预测模型

油气藏评价与开发 2024年第5期14卷 788-794页

作者：张思远杨佳坤宋丽娜周栋梁胡俊许锋施玉霞胥洪成裴根范家屹国家管网集团中原储气库有限责任公司中国石油勘探开发研究院

储气库是保障国家能源安全的重要手段，储气库多周期运行井控参数预测对储气库高效运行具有重要意义。为解决文23储气库目前注采运行动态规律认识不清，难以制定有效的储气库优化调整方案的问题，使用产量不稳定分析法为主的方法，建立... 详细信息

储气库是保障国家能源安全的重要手段，储气库多周期运行井控参数预测对储气库高效运行具有重要意义。为解决文23储气库目前注采运行动态规律认识不清，难以制定有效的储气库优化调整方案的问题，使用产量不稳定分析法为主的方法，建立储气库多周期运行井控参数预测模型，剖析井控参数随储气库开发的变化规律。首先，对文23储气库气井生产动态数据进行预处理，与储层参数一起输入至RTA软件中完成基础的数据整理及加载，并建立注采气组分相态模型，计算天然气高压物性参数；然后，根据气井压力恢复试井资料分析储气库地层渗流特征，建立及筛选最优井筒管流模型，用于计算气井井底压力；最后，使用Blasingame图版分析方法拟合井控参数建立基础模型，并通过拟合储气库气井生产数据，调整基础模型从而获得储气库多周期运行井控参数预测模型。使用所建井控参数预测模型对文23储气库气井多周期运行后井控参数进行预测，结果显示：可根据气井生产动态及井控特征将文23储气库气井分为3类，3类气井占比分别为39%、34%、27%；根据所建模型进行多周期井控参数变化分析，随着多周期注采运行，储气库多周期井控半径整体表现为初期增幅大，后期增幅减缓的趋势，储气库平均井控体积不断增加，3个类型的气井所控制储层的有效渗透率均呈先增加后稳定的趋势。

关键词：储气库产量不稳定分析井控特征井控参数参数预测

Revealing the low thermal conductivity of high-entropy rare-earth tantalates via multi-scale defect analysis

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Journal of Advanced Ceramics 2023年第11期12卷 2087-2100页

作者： jun Wang Qianqian Jin Jianbo Song Di Zhang Bin Xu Zhiyi Ren Meng Wang Shixiao Yan Xiaoliang Sun Chi Liu Xiaoyu Chong Jing feng Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China Materials Science and Engineering Research Center Guangxi University of Science and TechnologyLiuzhou 545006China Shanghai Electro–Mechanical Engineering Institute Shanghai 201109China Shanghai Spaceflight Precision Machinery Institute Shanghai 201109China

Thermal barrier coating(TBC)materials can improve energy conversion efficiency and reduce fossil fuel ***,novel rare earth tantalates RETaO_(4),as promising candidates for TBCs,were reassembled into multi-component solid solutions with a monoclinic structure to further depress thermal conductivity via an entropy *** formation mechanisms of oxygen vacancy defects,dislocations,and ferroelastic domains associated with the thermal conductivity are demonstrated by aberration-corrected scanning transmission electron *** to single-RE RETaO_(4)and 8YSZ,the intrinsic thermal conductivity of(5RE1/5)TaO4 was decreased by 35%–47%and 57%–69%at 1200℃,respectively,which is likely attributed to multi-scale phonon scattering from Umklapp phonon–phonon,point defects,domain structures,and dislocations.r¯3+RE/r5+Ta and low-temperature thermal conductivity are negatively correlated,as are the ratio of elastic modulus to thermal conductivity(E/κ)and high-temperature thermal ***,the high defects’concentration and lattice distortion in high-entropy ceramics enhance the scattering of transverse-wave phonons and reduce the transverse-wave sound velocity,leading to a decrease in the thermal conductivity and Young’s *** addition,5heC-1 has ultra-low thermal conductivity,moderate thermal expansion coefficients,and high hardness among three five-component high-entropy ***,5heC-1 with superior thermal barrier and mechanical properties can be used as promising thermal insulating materials.

关键词： thermal barrier coating(TBC) entropy strategy oxygen vacancy dislocation ferroelastic domains intrinsic thermal conductivity

健康档案建立对中青年流动人口慢性病患者健康管理服务利用的影响——以高血压和2型糖尿病为例

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现代预防医学 2024年第9期51卷 1630-1636页

作者：王楠吴群红冯亚杰张环宇刘俊萍刘智新刘伟梁立波哈尔滨医科大学卫生管理学院

目的了解中青年流动人口高血压和2型糖尿病患者建立健康档案对其接受健康管理服务的影响，为提高健康管理服务利用率，实现基本公共卫生服务均等化提供参考。方法基于2017年全国流动人口卫生计生动态监测数据中6 391名30～59岁中青年... 详细信息

目的了解中青年流动人口高血压和2型糖尿病患者建立健康档案对其接受健康管理服务的影响，为提高健康管理服务利用率，实现基本公共卫生服务均等化提供参考。方法基于2017年全国流动人口卫生计生动态监测数据中6 391名30～59岁中青年慢性病患者人口特征、家庭特征、健康与公共服务特征资料，运用Probit模型及倾向得分匹配法分析健康档案对中青年流动人口高血压及2型糖尿病患者接受健康管理服务的影响。结果 Probit模型结果显示，高血压患者、2型糖尿病患者及两病共患者建立健康档案的系数分别为0.940、0.905、1.333，且均在1%水平上显著，即建立健康档案对中青年流动人口慢性病患者接受健康管理服务有正向作用。纠正模型内生性问题后，这一结果仍然稳健。异质性分析发现建立健康档案对接受健康管理服务存在年龄、自评健康及健康教育差异。结论建立健康档案对中青年流动人口慢性病患者接受健康管理服务有正向影响。今后应关注中青年流动人口高血压和2型糖尿病患者的基本公共卫生服务需求，针对不同特征的患者开展健康教育宣传工作，提高基本公共卫生服务知晓率与使用率。

关键词：流动人口中青年慢性病患者健康档案健康管理服务

Entering the duodenal diverticulum:A method for cannulation of the intradiverticular papilla

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World Journal of Gastroenterology 2012年第48期18卷 7394-7396页

作者： Bao-Can Wang Wei-Bin Shi Wen-Jie Zhang jun Gu Yi-Jing Tao Yu-Qin Wang Xue-feng Wang Department of Gastroenterology Xinhua HospitalShanghai Jiaotong University School of Medicine Department of General Surgery Xinhua HospitalShanghai Jiaotong University School of Medicine

Successful cannulation of the common bile duct may be difficult in patients in whom the papilla is located entirely within a *** this study,we report successful biliary cannulation in three patients following intubation of the distal tip of the duodenoscope into the duodenal diverticulum and locating the major *** complications occurred during the operation or during the postoperative *** method didn't need second incubation an endoscope and might lower the burden of *** this skill is useful to deal with the papilla hidden inside the large diverticulum because of its safety and convenience.

关键词： Endoscopic retrograde cholangiopancrea-tography Intradiverticular papilla Duodenoscope

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一种小型化的低功耗短波红外成像组件设计

光学与光电技术 2024年第2期22卷 140-148页

作者：王瑞洪普宫文峰胡志强陈洲朱俊文华中光电技术研究所—武汉光电国家研究中心湖北武汉430223 湖北久之洋红外系统股份有限公司湖北武汉430299

短波红外兼具可见光与热红外的成像优点,近年来得到了快速的发展。现有的短波红外相机多应用于机载或车载平台,可以对快速移动的目标进行跟踪识别,但是存在尺寸重量较大、功耗成本较高等问题,限制了其在民用方向的推广。针对这一问题,... 详细信息

短波红外兼具可见光与热红外的成像优点,近年来得到了快速的发展。现有的短波红外相机多应用于机载或车载平台,可以对快速移动的目标进行跟踪识别,但是存在尺寸重量较大、功耗成本较高等问题,限制了其在民用方向的推广。针对这一问题,提出了一种低功耗、低成本、小型化的短波红外成像组件解决方案,降低帧频以精简信号处理架构;选择国产低功耗现场可编程门阵列(Field-Programmable Gate Array,FPGA)芯片;提高电源效率,在保证信噪比的前提下,单板面积减小到38 mm×38 mm,正常工作状态下功耗为2.8 W。在短波红外相机的尺寸和功耗方面都有了显著优化,降低了成本及装载要求,提升了续航能力,为民用方向的推广起到了一定的推动作用。

关键词： InGaAs探测器低功耗短波红外全差分运算放大器 TEC温度控制

Complex geometric modeling and tooth contact analysis of a helical face gear pair with arc-tooth

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Journal of Central South University 2022年第4期29卷 1213-1225页

作者： MO Shuai SONG Wen-hao ZHU Sheng-ping feng Zhi-you TANG Wen-jie GAO Han-jun School of Mechanical Engineering Tiangong UniversityTianjin 300387China Tianjin Key Laboratory of Modern Electromechanical Equipment Technology Tianjin 300387China State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China The State Key Laboratory of Virtual Reality Technology and Systems Beijing University of Aeronautics and AstronauticsBeijing 100083China

A complex geometric modeling method of a helical face gear pair with arc-tooth generated by an arc-profile cutting(APC)disc is proposed,and its tooth contact characteristics are ***,the spatial coordinate system of an APC face gear pair is established based on meshing *** the coordinate transformation matrix and the tooth profile of the cutter,the equations of the curve envelope of the APC face gear pair are *** the surface equations are solved to extract the point clouds data by programming in MATLAB,which contains the work surface and the fillet surface of the APC face gear *** the complex geometric model of the APC face gear pair is built by fitting its point *** last,through the analysis of the tooth surface contact,the sensitivity of the APC face gear to the different types of mounting errors is *** results show that the APC face gear pair is the most sensitive to mounting errors in the tooth thickness direction,and it should be strictly controlled in the actual application.

关键词： arc-tooth face gear complex geometric modeling point clouds mounting errors tooth contact analysis

Electronic properties of defects in Weyl semimetal tantalum arsenide

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Chinese Physics B 2018年第9期27卷 462-468页

作者： Yah-Long Fu Chang-Kai Li Zhao-jun Zhang Hai-Bo Sang Wei Cheng feng-Shou Zhang Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Beijing Radiation Center Beijing 100875China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of LanzhouLan＇zhou 730000China Ningbo h2stitute of Industrial Technology Chinese Academy of SciencesNingbo 315201China

The tantalum arsenide （TaAs） is a topological Weyl semimetal which is a class of materials of gapless with three- dimensional topological structure. In order to develop a comprehensive description of the topological properties of the Weyl semimetal, we use the density functional theory to study several defects of TaAs after H irradiation and report the electronic dispersion curves and the density of states of these defects. We find that various defects have different influences on the topological properties. Interstitial H atom can shift the Fermi level. Both Ta vacancy with a concentration of 1/64 and As vacancy with a concentration of 1/64 destruct a part of the Weyl points. The substitutional H atom on a Ta site could repair only a part of the Weyl points, while H atom on an As site could repair all the Wevl points.

关键词： Weyl semimetal first-principles calculations band structures density of states

母马补喂支链氨基酸对哺乳马驹生长性能和粪便菌群的影响

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中国畜牧兽医 2024年第8期51卷 3355-3364页

作者：刘笑天贾雨欣高凤袁鑫鑫王永发薛宇恒孟军曾亚琦李晓斌新疆农业大学动物科学学院新疆马繁育与运动生理重点实验室乌鲁木齐830052

[目的]本试验旨在探究泌乳期伊犁马母马补喂不同剂量的支链氨基酸(BCAAs)对哺乳期马驹生长性能和粪便菌群的影响,为保障马驹哺乳期生长及健康提供参考依据。[方法]选择泌乳期母马及其马驹各20匹(哺乳期马驹在2~3月龄之间,初始体重为97.6... 详细信息

[目的]本试验旨在探究泌乳期伊犁马母马补喂不同剂量的支链氨基酸(BCAAs)对哺乳期马驹生长性能和粪便菌群的影响,为保障马驹哺乳期生长及健康提供参考依据。[方法]选择泌乳期母马及其马驹各20匹(哺乳期马驹在2~3月龄之间,初始体重为97.60 kg±13.24 kg;泌乳期母马体重为392.90 kg±12.18 kg),随机分成4组,每组母马及其马驹各5匹,分别为对照组和试验Ⅰ组、Ⅱ组、Ⅲ组,在相同饲养管理条件下饲养67 d(预饲期7 d,试验期60 d)。试验期间,对照组与试验组母马每天补喂精料补充料2 kg,试验Ⅰ、Ⅱ、Ⅲ组母马分别额外补喂38、76、114 g/d BCAAs。试验前1 d和第60天测量马驹的体尺和体重数据,第60天采用直肠取粪法采集马驹粪便,分析马驹粪便菌群多样性。[结果]试验第60天,试验Ⅲ组马驹的胸围和体重显著高于对照组(P0.05)。试验Ⅱ组马驹粪便螺旋体菌门相对丰度显著高于对照组和试验Ⅰ组(P<0.05),毛螺旋菌科相对丰度显著高于对照组和试验Ⅲ组(P<0.05);试验Ⅰ和Ⅱ组的瘤胃球菌科相对丰度均显著高于对照组(P<0.05),试验Ⅲ组的理研菌科相对丰度显著高于对照组(P<0.05)。在属水平上,试验Ⅱ组密螺旋体属的相对丰度最高且显著高于试验Ⅰ组(P<0.05),且瘤胃球菌属相对丰度显著高于其他3个组(P<0.05);试验Ⅲ组普氏菌科未分类菌004相对丰度极显著高于对照组和试验Ⅰ组(P<0.01)。LEfSe分析与PICRUSt2功能预测所表现的差异项目均与肠道发酵代谢、短链脂肪酸的生产、氨基酸的代谢相关。[结论]给伊犁马母马补喂不同剂量的BCAAs可促进哺乳马驹胸围和体重的增长,提高其肠道有益菌群的丰度,降低有害菌群的丰度,以母马补喂76 g/d BCAAs效果最佳。

关键词：母马支链氨基酸马驹粪便菌群

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