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视疲劳患者近视力受损的发生率及影响因素 预览
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作者 王志玲 魏莹莹 +4 位作者 贾杨雪 周恩亮 张勇 柯根杰 顾永昊 《国际眼科杂志》 CAS 北大核心 2019年第10期1800-1804,共5页
目的:研究视疲劳患者中近视力受损的发生率及其影响因素。方法:选取2017-05/2018-05在我院门诊就诊的视疲劳患者51例102眼,根据日常生活近视力是否受损分为日常近视力受损组(24例)和无近视力受损组(27例),收集两组患者的一般资料,并进... 目的:研究视疲劳患者中近视力受损的发生率及其影响因素。方法:选取2017-05/2018-05在我院门诊就诊的视疲劳患者51例102眼,根据日常生活近视力是否受损分为日常近视力受损组(24例)和无近视力受损组(27例),收集两组患者的一般资料,并进行常规眼部检查、主觉验光和双眼眼动参数检测。结果:本组患者中裸眼近视力受损者27例(53%),日常生活近视力受损者24例(47%),无最佳矫正近视力受损者。日常近视力受损组患者年龄显著高于无近视力受损组,其中≥45岁的患者比例显著高于无近视力受损组(P<0.01)。两组患者中≥45岁的患者NRA/PRA、水平聚散力[BO(40cm)]、水平聚散幅度(40cm)均有明显差异(P<0.05)。结论:视疲劳患者多伴有近视力受损,年龄增大、正负相对调节不平衡是其发生的主要影响因素。 展开更多
关键词 近视力受损 视疲劳 眼动参数 调节幅度 老视
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Mechanisms and efficient elimination approaches of self-absorption in LIBS
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作者 侯佳佳 张雷 +7 位作者 赵洋 王哲 张勇 马维光 董磊 尹王保 肖连团 贾锁堂 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2019年第3期125-139,共15页
Laser-induced breakdown spectroscopy(LIBS)is a promising analytical spectroscopy technology based on spectroscopic analysis of the radiation emitted by laser-produced plasma.However,for quantitative analysis by LIBS,t... Laser-induced breakdown spectroscopy(LIBS)is a promising analytical spectroscopy technology based on spectroscopic analysis of the radiation emitted by laser-produced plasma.However,for quantitative analysis by LIBS,the so-called self-absorption effects on the spectral lines,which affect plasma characteristics,emission line shapes,calibration curves,etc,can no longer be neglected.Hence,understanding and determining the self-absorption effects are of utmost importance to LIBS research.The purpose of this review is to provide a global overview of self-absorption in LIBS on the issues of experimental observations and adverse effects,physical mechanisms,correction or elimination approaches,and utilizations in the past century.We believe that better understanding and effective solving the self-absorption effect will further enhance the development and maturity of LIBS. 展开更多
关键词 LASER-INDUCED BREAKDOWN spectroscopy(LIBS) SELF-ABSORPTION effect optically thin ELEMENTAL analysis
Squeezed back-to-back correlations of K^+K^- in d+Au collisions at √sNN=200 GeV and Au+Au collisions at √sNN=62.4 GeV
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作者 张勇 杨婧 吴卫华 《中国物理C:英文版》 SCIE CAS CSCD 2019年第7期61-69,共9页
We investigate the squeezed back-to-back correlations(BBC) of K^+K^-, caused by the mass modification of particles in the dense medium formed in d + Au collisions at √sNN= 200 GeV and Au + Au collisions at √sNN= 62.... We investigate the squeezed back-to-back correlations(BBC) of K^+K^-, caused by the mass modification of particles in the dense medium formed in d + Au collisions at √sNN= 200 GeV and Au + Au collisions at √sNN= 62.4 GeV. Considering that some kaons may not be affected by the medium, we further study the BBC functions of K+K-when parts of all kaons have a mass-shift. Our results indicate that the BBC functions of K+K-can be observed when only ~10% of all kaons have a mass-shift in d + Au collisions at √sNN = 200 GeV and the peripheral collisions of Au + Au at √sNN= 62.4 GeV. Since the BBC function is caused by the mass-shift due to the interactions between the particle and the medium, the successful detection of the BBC function indirectly marks that the dense medium has formed in these collision systems. We suggest the experimental measurement of the BBC function of K^+K^- in d + Au collisions at √sNN = 200 GeV and peripheral collisions of Au + Au at √sNN= 62.4 GeV. 展开更多
关键词 SQUEEZED BACK-TO-BACK CORRELATIONS K^+K^- mass modification DENSE medium
Extinction coefficients of surface atmospheric aerosol above LHAASO
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作者 皮文萱 黄敏 +5 位作者 祝凤荣 何钰 谢宁 张勇 陈起辉 贾焕玉 《中国物理C:英文版》 SCIE CAS CSCD 2019年第8期117-123,共7页
We investigate the extinction coefficients of the surface atmospheric aerosol over the Large High Altitude Air Shower Observatory (LHAASO), located at the Haizi Mountain, Daocheng County, China. To this end, we utiliz... We investigate the extinction coefficients of the surface atmospheric aerosol over the Large High Altitude Air Shower Observatory (LHAASO), located at the Haizi Mountain, Daocheng County, China. To this end, we utilize the Longtin model, Mie scattering theory, and experimental data obtained by the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO). Our theoretical calculations show that the total extinction coefficients of the atmospheric aerosol at the wavelength of 200–500 nm are inversely proportional to the laser wavelength, and influenced by the wind speed. From July 2015 to October 2016, the extinction coefficient of the surface atmospheric aerosols at 532 nm wavelength reached 0.04 km^-1 with no wind, while it increased to 0.1 km^-1 with gusts. In this period, the extinction coefficients of the surface atmospheric aerosol at 532 nm wavelength, obtained by the CALIPSO, change from 0.01 to 0.07 km^-1, which is less than the values obtained the theoretical calculation and larger than the average of Tibetan Plateau in 2006-2016. These calculations and experimental evidence provide important arguments to the model of atmospheric aerosol to be applied in the calibration of LHAASO. Our results suggest that the extinction coefficients over LHAASO require further study, including research on the size distribution, shape, concentration of aerosols particles, wind dependence, relative humidity dependence, etc. 展开更多
关键词 LHAASO EXTINCTION COEFFICIENT ATMOSPHERIC AEROSOL
葡萄膜巩膜途径降眼压机制治疗青光眼的研究进展 预览
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作者 张勇 朱小敏 谢琳 《国际眼科杂志》 CAS 北大核心 2019年第7期1131-1133,共3页
房水排出障碍导致的眼压升高是引起青光眼发病的主要原因,而降眼压仍是目前青光眼治疗的主要方法。房水外流主要通过传统的小梁网途径和非传统的葡萄膜巩膜途径,通过非压力依赖性的葡萄膜巩膜途径降低眼压以治疗青光眼越来越受到重视。... 房水排出障碍导致的眼压升高是引起青光眼发病的主要原因,而降眼压仍是目前青光眼治疗的主要方法。房水外流主要通过传统的小梁网途径和非传统的葡萄膜巩膜途径,通过非压力依赖性的葡萄膜巩膜途径降低眼压以治疗青光眼越来越受到重视。本文综述了应用药物和手术从葡萄膜巩膜途径降眼压机制治疗青光眼的研究进展。 展开更多
关键词 青光眼 眼压 葡萄膜巩膜途径
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船载浮式离心压缩机转子动力学特性分析 预览
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作者 太兴宇 李云 +2 位作者 杨树华 张勇 褚福磊 《风机技术》 2019年第1期63-70,I0009共9页
以船载浮式离心压缩机转子为研究对象,建立了考虑隔振器(AVM,anti-vibration mount)的转子-轴承-弹性基础动力学模型。由于实际波浪载荷作用周期长,所以在计算过程中,将由波浪载荷导致的复合基础运动考虑为静态加载,不考虑瞬态特性。基... 以船载浮式离心压缩机转子为研究对象,建立了考虑隔振器(AVM,anti-vibration mount)的转子-轴承-弹性基础动力学模型。由于实际波浪载荷作用周期长,所以在计算过程中,将由波浪载荷导致的复合基础运动考虑为静态加载,不考虑瞬态特性。基于这一点,计算了复合基础运动下的轴承特性以及整体惯性载荷,并分析了船载浮式离心压缩机转子的横向振动以及运行稳定性。通过分析发现,基础运动会影响轴承的动力特性,使轴承负载产生一个偏离角度,并导致轴承交叉耦合项增大。轴承动力特性的改变和隔振器的采用,会使得系统固有频率和不平衡响应发生明显变化,隔振器会使转子在最危险工况下的共振峰值明显减低。与此同时,基础运动会通过轴承以及密封运行间隙影响转子系统的稳定性,使对数衰减率降低,甚至会导致转子失稳,而隔振器可以改善转子的稳定性。 展开更多
关键词 船载浮式离心压缩机 转子动力学 复合基础运动 横向振动 稳定性
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饲料类型对茶尺蠖幼虫肠道细菌多样性及幼虫存活率的影响
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作者 张勇 赵天宇 +3 位作者 邓竣丹 吴珍珍 杨云秋 龙雁华 《微生物学报》 CAS CSCD 北大核心 2019年第5期881-890,共10页
【目的】茶尺蠖是茶园中的重要害虫。研究茶尺蠖寄主食物-肠道菌群-茶尺蠖生长发育三者之间的关系对于茶尺蠖的防治具有重要的理论指导价值。【方法】分析不添加茶叶因子的纯人工饲料和茶树鲜叶对茶尺蠖幼虫的存活影响;用高通量测序技... 【目的】茶尺蠖是茶园中的重要害虫。研究茶尺蠖寄主食物-肠道菌群-茶尺蠖生长发育三者之间的关系对于茶尺蠖的防治具有重要的理论指导价值。【方法】分析不添加茶叶因子的纯人工饲料和茶树鲜叶对茶尺蠖幼虫的存活影响;用高通量测序技术分析不同饲料饲喂的茶尺蠖幼虫的肠道菌群异同。【结果】取食人工饲料的幼虫死亡率远远高于取食茶树鲜叶的幼虫;取食人工饲料的幼虫肠道细菌多样性和丰富度高于取食茶树鲜叶的幼虫;茶尺蠖幼虫肠道中存在很多促进宿主生长的细菌。【结论】饲料类型影响茶尺蠖幼虫的存活;饲料类型影响茶尺蠖幼虫肠道菌群结构。 展开更多
关键词 肠道菌群 茶尺蠖幼虫 多样性 差异性
IBPSO-Based MUSIC Algorithm for Broken Rotor Bars Fault Detection of Induction Motors
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作者 Pan-Pan Wang Xiao-Xiao Chen +2 位作者 Yong Zhang Yong-Jun Hu Chang-Xin Miao 《中国机械工程学报:英文版》 SCIE EI CAS CSCD 2018年第5期48-57,共10页
In spectrum analysis of induction motor current, the characteristic components of broken rotor bars(BRB) fault are often submerged by the fundamental component. Although many detection methods have been proposed for... In spectrum analysis of induction motor current, the characteristic components of broken rotor bars(BRB) fault are often submerged by the fundamental component. Although many detection methods have been proposed for this problem, the frequency resolution and accuracy are not high enough so that the reliability of BRB fault detection is a ected. Thus, a new multiple signal classification(MUSIC) algorithm based on particle swarm intelligence search is developed. Since spectrum peak search in MUSIC is a multimodal optimization problem, an improved bare?bones particle swarm optimization algorithm(IBPSO) is proposed first. In the IBPSO, a modified strategy of subpopulation determination is introduced into BPSO for realizing multimodal search. And then, the new MUSIC algorithm, called IBPSO?based MUSIC, is proposed by replacing the fixed?step traversal search with IBPSO. Meanwhile, a simulation signal is used to test the e ectiveness of the proposed algorithm. The simulation results show that its frequency precision reaches 10-5, and the computational cost is only comparable to that of traditional MUSIC with 0.1 search step. Finally, the IBPSO?based MUSIC is applied in BRB fault detection of an induction motor, and the e ectiveness and superiority are proved again. The proposed research provides a modified MUSIC algorithm which has su cient frequency precision to detect BRB fault in induction motors. 展开更多
关键词 MUSIC MULTIMODAL Bare?bones particle SWARM optimization Induction motors Broken ROTOR bars Fault detection
Kaempferol protects ethanol-induced gastric ulcers in mice via pro-inflammatory cytokines and NO
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作者 Qinchen Li Xinxin Hu +7 位作者 Yanhan Xuan Jianghua Ying Yujia Fei Jielu Rong Yong Zhang Jian Zhang Chunyan Liu Zheng Liu 《生物化学与生物物理学报:英文版》 SCIE CAS CSCD 2018年第3期246-253,共8页
胃的溃疡(GU ) 是在全世界影响许多人的普通病理。过多的白酒消费是 GU 的主要原因之一;然而,仍然有为 GU 的预防或治疗的有效的药的缺乏。在这研究,我们在老鼠把保护的效果和 kaempferol (KAE ) 的可能的机制与尖锐导致乙醇的损害... 胃的溃疡(GU ) 是在全世界影响许多人的普通病理。过多的白酒消费是 GU 的主要原因之一;然而,仍然有为 GU 的预防或治疗的有效的药的缺乏。在这研究,我们在老鼠把保护的效果和 kaempferol (KAE ) 的可能的机制与尖锐导致乙醇的损害作比较到胃的 mucosa。Fasted 老鼠口头上地被给车辆(0.9% 盐) , omeprazole (20 mg/kg ) ,或为在在由有绝对乙醇(10 ml/kg ) 的挑战的 GU 模型的建立以前的不同试验性的集合的 1 h 的 KAE (40, 80,或 160 mg/kg ) 。动物是 euthanized 在乙醇吸入以后的 1 h,和他们的血浆和胃纸巾服从于进一步的检查。宏观、显微镜的损害,和免疫学的和生物化学的参数被观察。发炎的效果用下列指示物被调查:肿瘤坏死因素 --(TNF-) , interleukin-1 (IL-1 ) , IL-6, myeloperoxidase (军邮局) ,和氮的氧化物(没有) 。结果证明 KAE 显著地减少了溃疡索引,增加了预防索引,完全保护了 mucosa 免受损害,和保存胃的 mucosal glycoprotein 的伤害。KAE 减少了军邮局活动和支持 inflammatory cytokine (TNF- ,和 IL-1 ) 铺平,并且没改进层次。KAE 的 gastroprotective 活动可能被归因于胃的有粘液的 glycoproteins 层次的保藏,这样由禁止嗜中性的累积和军邮局活动,调整支持 inflammatory cytokines 的层次,并且不改进生产。 展开更多
关键词 CYTOKINES 乙醇 溃疡 保护 老鼠 生物化学 IL-6
Revisit of advection-dispersion equation model with velocity-dependent dispersion in capturing tracer dynamics in single empty fractures 预览
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作者 王沐 赵卫东 +3 位作者 Rhiannon Garrard Yong Zhang 刘咏 钱家忠 《水动力学研究与进展:英文版》 SCIE EI CSCD 2018年第6期1055-1063,共9页
An accurate quantification of the contaminant transport through fractured media is critical for dealing with water-quality related scientific and engineering issues, where the dispersion coefficient is an important an... An accurate quantification of the contaminant transport through fractured media is critical for dealing with water-quality related scientific and engineering issues, where the dispersion coefficient is an important and elusive parameter for the solute transport modeling. Many previous studies show that the dispersion coefficient(D) in the standard advection-dispersion equation(ADE) model can be approximated by D=αv^λ(where α is the dispersivity), a formula to be revisited systematically in this study by laboratory experiments and model analysis. First, a series of tracer transport experiments in single empty fractures are conducted in cases of different hydraulic gradients. Second, the tracer breakthrough curves are determined by simulations based on the ADE model, to obtain the dispersion coefficients corresponding to various fracture roughnesses and flow velocities. A varying trend of λ is analyzed under different flow conditions. Results show that although the standard ADE model cannot be used to characterize the late-time tailing of the tracer BTCs, likely due to the solute retention, this simple model can simulate most of the solute mass dynamics moving through fractures and may therefore provide information for estimating the dispersion in parsimonious models appropriate for the non-Fickian transport. The following three conclusions are drawn:(1) the peak of the breakthrough curves comes earlier with increasing the roughness, according to the ADE simulation,(2) the value of λ generally decreases as the relative roughness of the fracture increases,(3) the value of λ is approximately equal to 2.0 when the dispersion is dominated by the molecular diffusion in the smooth fracture. 展开更多
关键词 DISPERSION coefficient molecular diffusion ROUGHNESS variation trend SINGLE fracture
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塞来昔布对糖尿病大鼠视网膜缝隙连接蛋白Cx43的作用 预览
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作者 潘桂萍 田朕 +2 位作者 张勇 袁均 王雅琴 《国际眼科杂志》 CAS 北大核心 2018年第8期1389-1392,共4页
目的:观察COX-2(cyclooxygenase,COX-2)抑制剂(塞来昔布)对糖尿病大鼠视网膜缝隙连接蛋白Cx43(connexin43,Cx43)表达的影响。方法:选取SD(Sprague-Dawley)大鼠45只,随机分为3组:对照组、糖尿病组、用药组,每组各15只,采用ST... 目的:观察COX-2(cyclooxygenase,COX-2)抑制剂(塞来昔布)对糖尿病大鼠视网膜缝隙连接蛋白Cx43(connexin43,Cx43)表达的影响。方法:选取SD(Sprague-Dawley)大鼠45只,随机分为3组:对照组、糖尿病组、用药组,每组各15只,采用STZ腹腔注射造模的方式进行造模,快速血糖仪监测各组大鼠空腹血糖,正常对照组、糖尿病模型组、用药组分别用生理盐水、生理盐水、塞来昔布溶液进行灌胃,3mo后采用过量麻醉法处死大鼠,制备视网膜标本,采用免疫组化法观察Cx43蛋白,实时定量PCR技术检测大鼠视网膜Cx43mRNA的相对表达量,采用SPSS13.0统计软件进行统计分析,对各组检测结果进行比较。结果:免疫组织化学染色缝隙连接蛋白Cx43在视网膜大鼠的神经节细胞层、神经纤维层、内丛状层、色素上皮层、内皮细胞层可见表达不同程度点状、片状表达,计算机图像灰度分析发现塞来昔布对糖尿病大鼠视网膜Cx43表达有促进作用,正常对照组、糖尿病组、用药组灰度值分别是0.233±0.025、0.124±0.014、0.197±0.021,两两比较差异均有统计学意义(P〈0.05);实时定量PCR检测发现塞来昔布促进糖尿病大鼠Cx43 mRNA表达量增加,正常对照组、糖尿病组、用药组相对表达量分别是0.635±0.084、0.110±0.061、0.367±0.074,两两比较差异有统计学意义(P〈0.05)。结论:缝隙连接蛋白Cx43在糖尿病大鼠视网膜中表达减少,塞来昔布可以减缓糖尿病大鼠视网膜缝隙连接蛋白Cx43表达的减少。 展开更多
关键词 糖尿病视网膜病变 塞来昔布 CX43
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Passive round-robin differential-quadrature-phase-shift quantum key distribution scheme with untrusted detectors
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作者 刘宏伟 屈文秀 +3 位作者 窦天琦 王吉鹏 张勇 马海强 《中国物理B:英文版》 SCIE EI CAS CSCD 2018年第10期208-215,共8页
关键词 知更鸟 钥匙 分发 测量设备 QKD 相容性 协议 特征
响应曲面法研究二次铝灰中AlN水解对水解后残渣分形维数的影响 预览
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作者 张勇 郭朝晖 +1 位作者 韩自玉 肖细元 《中国有色金属学报:英文版》 SCIE EI CAS CSCD 2018年第12期2574-2581,共8页
利用响应曲面方法研究二次铝灰中AlN水解条件对水解后残渣分形维数的影响。研究结果表明,AlN水解显著影响水解后残渣分形维数。在303~373K温度下,AlN水解标准状态下可自发进行,水解液固比显著影响水解后残渣分形维数(p<0.05),残渣维... 利用响应曲面方法研究二次铝灰中AlN水解条件对水解后残渣分形维数的影响。研究结果表明,AlN水解显著影响水解后残渣分形维数。在303~373K温度下,AlN水解标准状态下可自发进行,水解液固比显著影响水解后残渣分形维数(p<0.05),残渣维数实际变化范围为1.16~1.80,与计算值吻合度较高。此外,水解温度与水解时间之间交互作用,液固比与水解时间之间交互作用影响水解后残渣分形维数(p<0.01)。当二次铝灰中AlN水解优化条件为水解温度30℃、水解液固比5mL/g和水解时间10min时,残渣最小分形维数达到1.15。为提高二次铝灰综合利用,响应曲面法可以优化AlN水解条件以获得较小分形维数的残渣。 展开更多
关键词 二次铝灰 AlN水解 分形维数 优化 响应曲面
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High-Efficiency Wide-Band Cross-Polarization Conversion Using Bi-layered Metal Hole Pairs
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作者 张勇 李先科 黄成平 《中国物理快报:英文版》 SCIE CAS CSCD 2018年第10期40-43,共4页
关键词 极化变换器 金属 宽带 电影 红外线 电磁波 试验性 微波
Cascading failure in multilayer networks with dynamic dependency groups*
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作者 金磊 王小娟 +1 位作者 张勇 由婧文 《中国物理B:英文版》 SCIE EI CAS CSCD 2018年第9期645-651,共7页
关键词 复杂网络 串联 组织 连接部件 坚韧性 依存关系 恢复机制 影响因素
Quasars in the Galactic Anti-Center Area from LAMOST DR3
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作者 Zhi-Ying Huo Xiao-Wei Liu +11 位作者 Jian-Rong Shi Mao-Sheng Xiang Yang Huang Hai-Bo Yuan Jian-Nan Zhang Wei Zhang Jian-Ling Wang Yu-Zhong Wu Zi-Huang Cao Yong Zhang Yong-Hui Hou Yue-Fei Wang 《天文和天体物理学研究:英文版》 SCIE CAS CSCD 2017年第4期7-10,共4页
We present a sample of quasars discovered in an area near the Galactic Anti-Center covering150?≤ l ≤ 210?and |b| ≤ 30?,based on LAMOST Data Release 3(DR3).This sample contains 151 spectroscopically confirmed quasar... We present a sample of quasars discovered in an area near the Galactic Anti-Center covering150?≤ l ≤ 210?and |b| ≤ 30?,based on LAMOST Data Release 3(DR3).This sample contains 151 spectroscopically confirmed quasars.Among them 80 are newly discovered with LAMOST.All these quasars are very bright,with i magnitudes peaking around 17.5 mag.All the new quasars were discovered serendipitously from objects that were originally targeted with LAMOST as stars having bluer colors,except for a few candidates targeted as variable,young stellar objects.This bright quasar sample at low Galactic latitudes will help fill the gap in the spatial distribution of known quasars near the Galactic disk that are used to construct an astrometric reference frame for the purpose of accurate proper motion measurements that can be applied to,for example,Gaia.They are also excellent tracers to probe the kinematics and chemistry of the interstellar medium in the Milky Way disk and halo via absorption line spectroscopy. 展开更多
关键词 LAMOST 类星体 银河系 中心区域 数据发布 精确测量 空间分布 参考框架
Mass production of magnetocaloric LaFeMnSiB alloys with hydrogenation
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作者 Tao Zhang Cheng-yong Wang +2 位作者 Lugee Li Yong Zhang Cui-lan Liu 《钢铁研究学报:英文版》 SCIE EI CAS CSCD 2017年第4期462-468,共7页
LaFe_(11.39)Mn_(0.35)Si_(1.26)B_(0.1)Hxalloys were prepared by hydrogenation.Samples were annealed at 1343Kfor30-90 hto form the NaZn13 phase.La-rich andα-Fe secondary phases were also detected.Saturated hydrogenatio... LaFe_(11.39)Mn_(0.35)Si_(1.26)B_(0.1)Hxalloys were prepared by hydrogenation.Samples were annealed at 1343Kfor30-90 hto form the NaZn13 phase.La-rich andα-Fe secondary phases were also detected.Saturated hydrogenation at 553 Kand 0.15 MPa of H_2 pressure for 5hwas employed to improve the Curie temperature of the alloys to 279 K.The maximum magnetic entropy change,relative cooling power,and adiabatic temperature change of LaFe_(11.39)Mn_(0.35)Si_(1.26)B_(0.1)H_x annealed at 1343 Kfor 90hafter hydrogen absorption are 6.38J/(kg·K)(magnetic changesμ0ΔH =1.65T),100.1J/kg(μ0ΔH =1.65T),and 2.2 K(μ0ΔH =1.48T),respectively.Although the maximum magnetic entropy change of the LaFe_(11.39)Mn_(0.35)Si_(1.26)B_(0.1)H_x alloys is lower than those of similar alloys with high purity raw materials,the relative cooling power is nearly the same.The effect of impurities of the raw materials used was also discussed.It is assumed that the impurity of 0.2wt.% Al is responsible for the reduced entropy change of the resulted alloys.The LaFe_(11.39)Mn_(0.35)Si_(1.26)B_(0.1)H_x alloys prepared by this method could be a low cost alternative material for room temperature magnetic cooling applications. 展开更多
Candidate members of the Pal 5, GD-1, Cetus Polar and Orphan tidal stellar halo streams from SDSS DR9, LAMOST DR3 and APOGEE catalogs
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作者 Guang-Wei Li Brian Yanny +8 位作者 Hao-Tong Zhang Zong-Rui Bai Yue Wu Yi-Qiao Dong Ya-Juan Lei Hai-Long Yuan Yong-Hui Hou Yue-Fei Wang Yong Zhang 《天文和天体物理学研究:英文版》 SCIE CAS CSCD 2017年第6期117-128,共12页
We present candidate members of the Pal 5,GD-1,Cetus Polar and Orphan tidal stellar streams found in LAMOST DR3,SDSS DR9 and APOGEE catalogs.In LAMOST DR3,we find 20,4 and 24 high confidence candidates of tidal stream... We present candidate members of the Pal 5,GD-1,Cetus Polar and Orphan tidal stellar streams found in LAMOST DR3,SDSS DR9 and APOGEE catalogs.In LAMOST DR3,we find 20,4 and 24 high confidence candidates of tidal streams GD-1,Cetus Polar and Orphan respectively.We also list 59,118 and 10 high confidence candidates of tidal streams Cetus Polar,Orphan and Pal 5,respectively from the SDSS DR9 spectroscopic catalog.Furthermore,we find seven high confidence candidates of the Pal 5 tidal stream in the APOGEE data.Compared with SDSS,the new candidates from LAMOST DR3 are brighter,so that together,more of the color-magnitude diagram,including the giant branch,can be explored.Analysis of the SDSS data shows that there are three metallicity peaks associated with the Orphan stream which also exhibit some spatial separation.The LAMOST data confirm multiple metallicities in this stream.The metallicity,given by the higher resolution APOGEE instrument,of the Pal 5 tidal stream is [Fe/H] ~-1.2,higher than that given earlier by SDSS spectra.Many previously unidentified stream members are tabulated here for the first time,along with existing members,allowing future researchers to further constrain the orbits of these objects as they move within the Galaxy's dark matter potential. 展开更多
The metallicity of K giant stars along the Sagittarius streams
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作者 Hong-Bo Ren Wei-Bin Shi +4 位作者 Xu Zhang Yan-Ke Tang Yong Zhang Yong-Hui Hou Yue-Fei Wang 《天文和天体物理学研究:英文版》 SCIE CAS CSCD 2017年第7期121-128,共8页
大天空区域多目标纤维分光镜的望远镜(LAMOST ) 数据版本 3 向 341 691 颗 K 巨大的星提供了星的参数。基于法律与 Majewski 的模型,我们在与人马座(Sgr ) 矮子星系联系的领先的溪流识别了 252 颗 K 巨大的恒星。我们获得了用 Belokur... 大天空区域多目标纤维分光镜的望远镜(LAMOST ) 数据版本 3 向 341 691 颗 K 巨大的星提供了星的参数。基于法律与 Majewski 的模型,我们在与人马座(Sgr ) 矮子星系联系的领先的溪流识别了 252 颗 K 巨大的恒星。我们获得了用 Belokurov 等的模型属于 Sgr 的后面的手臂的 132 颗 K 巨大的星。我们沿着溪流学习了成员星的 metallicity 分发并且在第一发现了一个扁平的坡度领先的溪流包,在第二领先的溪流并且在第一包后面的溪流包。而且,我们从文学与我们的样品和数据获得了一个联合 metallicity 坡度。我们也分析了 overdensity 的性质,它位于 Sgr 的领先的溪流。 展开更多
关键词 金属丰度 人马座 巨星 LAMOST 地塞米松 丰度梯度 天文望远镜 大天区面积
Handgrip Strength as a Predictor of Nutritional Status in Chinese Elderly Inpatients at Hospital Admission 预览
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作者 ZHANG Xin Sheng LIU Ying Hua +7 位作者 ZHANG Yong XU Qing YU Xiao Ming YANG Xue Yan LIU Zhao LI Hui Zi LI Feng XUE Chang Yong 《生物医学与环境科学:英文版》 SCIE CAS CSCD 2017年第11期802-810,共9页
ObjectiveTo 估计营养的地位并且在老 inpatients.MethodsA 为营养不良或营养的风险定义性特定、年龄特定的有力的握手力量(HGS ) 切割点价值 1,343 个老住院病人的代表性的学习在中国 PLA 医院将军被进行。屏蔽的营养风险(NRS 2002 ) ... ObjectiveTo 估计营养的地位并且在老 inpatients.MethodsA 为营养不良或营养的风险定义性特定、年龄特定的有力的握手力量(HGS ) 切割点价值 1,343 个老住院病人的代表性的学习在中国 PLA 医院将军被进行。屏蔽的营养风险(NRS 2002 ) 和主观全球评价(SGA ) 被管理。人体测量的大小和血生物化学的指示物用标准技术被获得。操作特征(巨鸟) 曲线的性特定、年龄特定的接收装置被构造由 SGA 和 NRS 2002 为营养的地位评估 HGS。在曲线(AUC ) 下面的敏感,特性,和区域是到 NRS 2002 和 SGA 的 calculated.ResultsAccording, 63.81% 老住院病人在营养的风险, 28.22% 是营养不良的。有更高的 HGS 的病人有营养不良的独立地减少的风险和营养的风险。AUC 在 0.670 和 0.761 之间变化了。根据 NRS 2002,最佳的 HGS 切割点为女人为男人和 17.0 kg 和 14.6 kg (75-90 年)(65-74 年) 是 27.5 kg (65-74 年) 和 21.0 kg (75-90 年) 。根据 SGA,最佳的 HGS 切割点为男人和 15.2 kg 和 13.5 kg (75-90 年)(65-74 年) 是 24.9 kg (65-74 年) 和 20.8 kg (75-90 年) 因为 women.ConclusionElderly 住院病人增加了营养不良或营养的风险的发生。HGS 切割点能被用于在中国在医院承认在老住院病人估计营养的地位。 展开更多
关键词 有力的握手力量 老住院病人 营养评价 营养地位 营养不良
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