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Enhancement of red emission by co-dopant Ln^(3+) ions in Eu^(3+) :LaOF nanoparticles

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Science China(Physics,Mechanics & Astronomy) 2013年第5期56卷 928-932页

作者： FU zhenxing zheng HaiRong HE EnJie GAO Wei LI GuiAn College of Physics and Information Technology Shaanxi Normal University College of Physics and Information Technology Ningxia Normal University

Fluoride nanoparticles of Ln3＋（Ln3＋=Pr3＋, Nd3＋, Sm3＋, Cod3＋,Tb3＋ Dy3＋, I-I03＋, Er3＋, Tm3＋, yb3＋）/Eu3＋：LaOF and Eu3＋：LaOF with rhombohedral crystal structure were prepared by a hydrothermal-sintering method. The red fluorescence emission of Eu3＋ ions was found to be enhanced with most of the co-dopant Ln3. ions. Compared with strong fluorescence emission at 610 nm of Eu3＋：LaOF nanoparticles, the enhancement factors was up to ten times in Ln3~ （Ln3＋=Gd3＋, Dy3＋, Tm3＋）FEu3＋：LaOF co-doped nanoparticles. The results show that the asymmetry of the local environment of Eu3＋ ion was reduced by co-doping Ln3＋ ion into the nanoparticles, and that energy transfer might occur between Eu3_ and codopant Ln3＋ ions, which is suggested as the source of the observed fluorescence enhancement.

关键词： fluorescence enhancement Ln3+/Eu3+:LaOF nanoparticles asymmetry ratio

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无源电光式传感器及其进展

传感器技术 1999年第3期18卷 5-7页

作者：谢彦召郑振兴焦杰西北核技术研究所

基于晶体的电光效应原理、利用光纤传输制作的电光式传感器具有宽频带、抗干扰能力强、对被测对象扰动极小、灵敏度高等突出优点，可以对复杂环境中或小空间内的ＥＭＰ场进行高保真的测量。论述了电光式传感器的原理及其发展应用情况。

关键词：电光效应光纤传感器无源电光式传感器

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不同阻垢剂官能团对脱硫石膏结晶的影响

锅炉技术 2024年第4期55卷 1-6页

作者：赫祥宇肖海平周政梁伦涛雷兢韩振兴华北电力大学能源动力与机械工程学院北京102206

为评价不同循环水阻垢剂成分对脱硫石膏品质的作用,选用含特定官能团的6种单一成分阻垢剂进行成核试验和生长试验,研究其对石膏结晶过程的影响。成核试验中,含磺酸基阻垢剂使石膏结晶诱导时间缩短3.2%,磺酸基提高硫酸钙过饱和度,有利于... 详细信息

为评价不同循环水阻垢剂成分对脱硫石膏品质的作用,选用含特定官能团的6种单一成分阻垢剂进行成核试验和生长试验,研究其对石膏结晶过程的影响。成核试验中,含磺酸基阻垢剂使石膏结晶诱导时间缩短3.2%,磺酸基提高硫酸钙过饱和度,有利于石膏成核。含膦酸基和羧基阻垢剂使石膏结晶诱导时间延长6.5%~45.2%,抑制石膏成核。生长试验中,含磺酸基阻垢剂使石膏粒径减小30.3%,细碎石膏结晶增多。含膦酸基和羧基阻垢剂使石膏粒径增大21.5%~72.6%,石膏形貌发生畸变,出现片状孪晶。膦酸基和羧基主要通过吸附作用使石膏特定位置生长速率改变,使石膏发生畸变,有利于石膏生长。因此,含羧基官能团的阻垢剂对石膏品质负面影响最小,更适合作为全厂废水零排放背景下的循环水阻垢剂。

关键词：脱硫石膏阻垢剂晶体生长

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雷达动目标显示对消器性能分析

雷达与对抗 2024年第1期44卷 26-30页

作者：李振兴王康郑林谭宏星 63889部队河南孟州454750

基于动目标显示对消器模型,着重分析递归三次对消器前馈和反馈支路参数对动目标显示性能的影响;仿真对比不同对消器系数对凹口宽度、通带平坦度和改善因子等性能的影响;结合仿真实验进行验证。仿真结果表明递归三次对消器能够获得更优... 详细信息

基于动目标显示对消器模型,着重分析递归三次对消器前馈和反馈支路参数对动目标显示性能的影响;仿真对比不同对消器系数对凹口宽度、通带平坦度和改善因子等性能的影响;结合仿真实验进行验证。仿真结果表明递归三次对消器能够获得更优的通带平坦度,有利于提高待检测信号的信噪比。

关键词： MTI 固定地杂波反馈支路通带平坦度改善因子

Structure characteristics and microwave dielectric properties of Pr_(2)(Zr_(1-x)Ti_(x))_(3)(MoO_(4))_(9) solid solution ceramic with a stable temperature coefficient

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Journal of Materials Science & Technology 2022年第21期116卷 121-129页

作者： Huanrong Tian Jinjie zheng Lintao Liu Haitao Wu Hideo Kimura Yizhong Lu zhenxing Yue School of Environmental and Material Engineering Yantai UniversityYantai 264005China School of Materials Science and Engineering University of JinanJinan 250022China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Pr_(2)(Zr_(1−x)Ti_(x))_(3)(MoO_(4))_(9)(x=0.1-1.0)ceramics were prepared via a conventional solid-state method,the dependence of crystal structure and bond characteristics on microwave dielectric properties was investigated *** X-ray diffraction patterns indicated that the single-phase Pr_(2)Zr_(3)(MoO_(4))_(9)structure was formed in all the *** the Ti^(4+)content increased,the lattice volume gradually decreased,which was ascribed to the fact that the ionic radius of Ti^(4+)was smaller than that of Zr^(4+).Notably,outstanding microwave dielectric properties withεr of 10.73-16.35,Q·f values of 80,696-18,726 GHz and minorτ_(f) values−14.1-−2.6 ppm/℃were achieved in Pr_(2)(Zr_(1−x)Ti_(x))_(3)(MoO_(4))_(9)***ε_(r) increased with the rising x values,which was associated with the increase ofα/Vm *** decreasing Q·f was affected by the decline of lattice energy of[Zr/TiO_(6)]***τf value was dominated by[Zr/TiO_(6)]octahedral distortion,Mo-O bond energy,bond strength and B-site bond ***,infrared reflection spectra suggested that the properties were mainly caused by the absorption of phonon,and the dielectric loss could be further reduced by optimizing the experimental process.

关键词： Pr_(2)(Zr_(1-x)Ti_(x))_(3)(MoO_(4))_(9) Normalized bond length Bond characteristics Raman spectra

A Robotic System with Robust Remote Center of Motion Constraint for Endometrial Regeneration Surgery

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Chinese Journal of Mechanical Engineering 2022年第4期35卷 169-181页

作者： Jianhua Li Chongyang Wang zhenxing Wang Xiong zheng Zhidong Wang Jichun Tan Hao Liu State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169China University of Chinese Academy of Sciences Beijing 100049China Shenyang Jianzhu University Shenyang 110168China Chiba Institute of Technology Chiba 275-0016Japan Shengjing Hospital of China Medical University Shenyang 110016China

Surgical robots have been widely used in diferent procedures to improve and facilitate the ***,there is no robot designed for endometrial regeneration surgery,which is a new therapy for restoring fertility in women using stem *** regeneration surgery requires processing of the endometrium and transplantation of stem cells with minimal trauma to the *** this paper,we introduce a surgical robotic system that consists of a dexterous hysteroscope,supporting arm,and additional novel instruments to facilitate the operation and decrease trauma to the *** center of motion(RCM)constraint is required to protect the cervix of the ***,the supporting arm and hysteroscope are controlled separately in kinematics to ensure that the RCM constraint and hysteroscope’s shape and posture are ***,a task-decoupled method is used to improve the robustness of the RCM *** confrm that the proposed method is more robust and achieves higher RCM *** addition,the master-slave control of a robot with RCM constraint is also *** study proposes the realization of a robot with robust RCM control for endometrial regeneration surgery.

关键词： Endometrial regeneration Surgical robot Remote center of motion Task decoupled

Prevalence of physical fitness in Chinese school-aged children： Findings from the 2016 Physical Activity and Fitness in China -The Youth Study

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Journal of Sport and Health Science 2017年第4期6卷 395-403页

作者： zheng Zhu Yang Yang zhenxing Kong Yimin Zhang Jie Zhuang Shanghai Research Center for Physical Fitness and Health of Children and Adolescents Shanghai University of Sport Shanghai 200438 China School of Kinesiology Shanghai University of Sport Shanghai 200438 China Shanghai Municipal Center for Students' Physical Fitness and Health Surveillance Shanghai Municipal Education Committee Shanghai 200011 China Key Laboratory of Exercise and Physical Fitness Ministry of Education Beijing Sport University Beijing 100084 China

Purpose： This study was to present the 2016 prevalence estimates of Chinese school-aged children meeting physical fitness standards and to examine differences by sex and residence locales in children who did not meet fitness standards. Methods： We conducted cross-sectional analyses of 171,991 children and adolescents （boy： 50.0%, Grades 1-12） who participated in the 2016 Physical Activity and Fitness in China--The Youth Study. The main outcomes were fitness measures, assessed by the 2014 revised Chinese National Student Physical Fitness Standard （CNSPFS）, covering areas of aerobic capacity, upper body strength, flexibility, body mass index, abdominal strength, and trunk strength. Children＇s overall physical fitness performance was categorized, per CNSPFS standards, as excellent, good, pass, or no pass. Data on the prevalence of physical fitness categories and not meeting fitness standards （i.e., among children who received a ＂no pass＂ mark） were analyzed, through logistic regression, by sex （boy, girl） and residence locales （urban, rural） across 3 school grades （primary, junior middle, and junior high）. Results： In 2016, 5.95% of Chinese children and adolescents achieved an ＂excellent＂ mark, 25.80% received a ＂good＂ rating, 59.90% received a ＂pass＂, and 8.35% received a ＂no pass＂. Overall, boys were more likely to not pass the fitness standards compared with girls （adjusted odds ratio （aOR） = 1.710; 95% confidence interval （CI）： 1.708-1.712） and children living in urban areas were more likely to not pass the standards than those living in rural areas （aOR = 1.298; 95%CI： 1.296-1.299）. Consistent patterns of not meeting fitness standards were also found by sex and residence locales across all 3 school grades. Conclusion： In the Chinese school-aged population, about 3 in 10 children achieved an ＂excellent＂ or ＂good＂ fitness standard in 2016, and about 8% of this population did not meet CNSPFS standards. Children living in urban areas were more likely to not meet minim

关键词： Cardiorespiratory endurance Children Fimess Flexibility Muscular strength Physical activity

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难选氧化锑矿工艺矿物学及选矿回收

矿冶 2024年第3期33卷 383-390页

作者：王振兴郑永兴黄翔解晓晨省部共建复杂有色金属资源清洁利用国家重点实验室昆明650093 昆明理工大学国土资源工程学院昆明650093 广东粤桥新材料科技有限公司广东茂名525000

采用X射线荧光光谱分析、化学多元素分析、X射线衍射分析、电子探针分析对某氧化锑矿进行工艺矿物学研究,结果表明原矿中锑的含量仅为1.21%,含锑矿物为锑华、辉锑矿,脉石矿物为石英,并且原矿性脆、易泥化,属低品位难选氧化锑矿。在工艺... 详细信息

采用X射线荧光光谱分析、化学多元素分析、X射线衍射分析、电子探针分析对某氧化锑矿进行工艺矿物学研究,结果表明原矿中锑的含量仅为1.21%,含锑矿物为锑华、辉锑矿,脉石矿物为石英,并且原矿性脆、易泥化,属低品位难选氧化锑矿。在工艺矿物学研究结果的基础上开展对该矿的回收探索试验。采用分级—重选法对矿石进行选别,首先将原矿分级后获得+74μm和-74μm两种产品;对+74μm粒级产品采用磨矿—螺旋溜槽粗选—摇床精选的分选工艺流程进行处理,其中用螺旋溜槽选别-74μm占比为28.03%的原矿,获得的螺旋溜槽粗精矿中Sb品位2.01%、Sb作业回收率28.49%,在此基础上用摇床对螺旋溜槽粗精矿进行精选获得Sb品位6.03%、Sb作业回收率56.90%的摇床精矿;对-74μm粒级产品用悬振锥面选矿机进行选别,获得Sb品位4.87%、Sb作业回收率26.12%的锑精矿。在合适的磨矿细度下,通过多级重选以及多种重选设备的组合,可有效回收该氧化锑矿中的含锑矿物。研究结果可为该难选氧化锑矿的综合回收提供参考。

关键词：氧化锑矿重选摇床螺旋溜槽悬振锥面选矿机细粒选矿

Anisotropy of Bi_(2)Sr_(2)CaCu_(2)O_(y) Superconducting Single Crystals Under High Pressure

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Chinese Physics Letters 1991年第1期8卷 29-32页

作者： LIU zhenxing zheng Dongning YAN Yifeng WANG Jihong WANG Lijun ZHAO Zhongxian Institute of Physics Academia SinicaBeijing 100080

It is shown that there exists the anisortropic nature of pressure dependence for the superconducting transition temperature and resistivity in Bi_(2)Sr_(2)CaCu_(2)O_(y) single *** maximum superconducting critical temperature and the minimum resistance along a-b plane under about 8kbar have been observed,no obvtous structure phase transition was observed at room temperature under pressure,and there is not the same behaviour along the c axis up to 13kba.r.A slight difference between the rates dT_(c)/dP along a-6 plane and c axis was also *** anisotropy may have close relation to the coupling between layers.

关键词： resistance plane Crystal