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ICP-MS及AAS法测定川明参的无机营养元素

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中药材 2017年第12期40卷 2788-2794页

作者：杨晓阳岳媛黄红梁士贤林芷珊李晶吕光华成都中医药大学药学院/中药材标准化教育部重点实验室四川成都611137 重庆市中药研究院重庆400065 香港浸会大学化学系

目的:建立川明参药材中无机营养元素含量的测定方法,并比较不同产地川明参的营养元素。方法:从四川省8个川明参种植县/区采集23份川明参样品,根据地理位置,将其产地分为A(德阳市中江县和成都市金堂县和青白江区)、B(绵阳市盐亭县)、C(... 详细信息

目的:建立川明参药材中无机营养元素含量的测定方法,并比较不同产地川明参的营养元素。方法:从四川省8个川明参种植县/区采集23份川明参样品,根据地理位置,将其产地分为A(德阳市中江县和成都市金堂县和青白江区)、B(绵阳市盐亭县)、C(南充市阆中市、巴中市巴州区、广元市苍溪县)、D(达州万源市)产区。采用微波消解-ICP-MS及AAS法测定这些样品中13种营养元素的含量,并运用主成分分析法及t检验法对其所含元素进行评价。结果:23份川明参样品中13种无机营养元素的含量均在一定范围之内,平均值分别为0.026μg/g(Li)、6.105μg/g(B)、7.638μg/g(Mn)、56.139μg/g(fe)、0.031μg/g(Co)、3.695μg/g(Zn)、0.041μg/g(Se)、7.252μg/g(Sr)、0.022μg/g(Mo)、115.417μg/g(Na)、785.896μg/g(Mg)、7 356.074μg/g(K)、282.205μg/g(Ca)。尽管这些不同产地样品中元素的含量不同,但各自的指纹图谱却呈相似的波浪式分布态势。t检验结果表明,Se、Zn、Mn、Co、fe、Mg元素的含量在4个产区之间有显著性差异,其余元素含量差异不显著。主成分分析法提取前6个因子的综合得分模型为f=3.295C_1+2.341C_2+2.131C_3+1.362C_4+1.061C_5+0.734C_6。4个产区综合得分由高至低的顺序为D(0.917,n=5)、A(0.180,n=6)、B(-0.381,n=3)、C(-0.400,n=9)。结论:ICP-MS法和AAS法能够快速、准确的测定川明参中营养元素的含量。以无机营养元素为指标,川明参的营养价值较高,为滋补佳品。从无机营养元素的含量考虑,D产区(达州万源市)为栽培川明参的适宜产区。

关键词：川明参无机元素 ICP-MS AAS 主成分分析

Superelasticity and tunable thermal Expansion across a Wide temperature Range

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Journal of Materials Science & technology 2016年第8期32卷 705-709页

作者： Y.L. Hao H.L. Wang t. Li J.M. Cairney A.V. Ceguerra Y.D. Wang Y. Wang D. Wang E.G. Obbard S.J. Li R. Yang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Aerospace Mechanical & Mechatronic Engineering University of Sydney Sydney NSW2006 Australia Australian Centre for Microscopy and Microanalysis University of Sydney Sydney HSW2006 Australia State Key Laborotory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China State Key Laboratory for Mechanical Behavior of Materials and frontier Institute of Science and technology Xi'an Jiaotong Univemity Xi'an 710049 China Department of Materials Science and engineering Ohio State University Columbus OH 43210 USA Department of Electrical engineering and telecommunications University of New South Wales Sydney NSW2052 Australia

Materials that undergo a reversible change of crystal structure through martensitic transformation （Mt） possess unusual functionalities including shape memory, superelasticity, and low/negative thermal ex- pansion. these properties have many advanced applications, such as actuators, sensors, and energy conversion, but are limited typically in a narrow temperature range of tens of kelvin. Here we report that, by creating a nano-scale concentration modulation via phase separation, the Mt can be rendered continuous by an in-situ elastic confinement mechanism. through a model titanium alloy, we demon- strate that the elastically confined continuous Mt has unprecedented properties, such as superelasticity from below 4.2 K to 500 K, fully tunable and stable thermal expansion, from positive, through zero, to negative, from below 4.2 K to 573 K, and high strength-to-modulus ratio across a wide temperature range. the elastic tuning on the Mt, together with a significant extension of the crystal stability limit, provides new opportunities to explore advanced materials.

关键词： ti alloy Superelasticity thermal expansion behavior temperature characteristic

turbulent hydrodynamics experiments in high energy density plasmas： scientific case and preliminary results of the turboHEDP project

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High Power Laser Science and Engineering 2018年第3期6卷 50-64页

作者： A. Casner G. Rigon B. Albertazzi th. Michel t. Pikuz A. faenov P. Mabey N. Ozaki Y. Sakawa t. Sano J. Ballet P. tzeferacos D. Lamb E. falize G. Gregori M. Koenig Universite de Bordeaux-CNRS-CEA CELIA (CEntre Lasers Intenses et Applications) UMR 5107 F-33405 Talence France LULI- CNRS Ecole Polytechnique CEA Universite Paris-Saclay UPMC Univ Paris 06 : Sorbonne Universites -F-91128 Palaiseau cedex France ENS Lyon Universite de Lyon CHELS 69342 Lyon France Open and transdisciplinary Research Initiatives Osaka University Suita Osaka 565-0871 Japan Joint Institute for High temperature RAS Moscow 125412 Russia Graduate School of Engineering Osaka University Suita Osaka 565-0871 Japan Institute of Laser Engineering Osaka University Suita Osaka 565-0871 Japan Laboratoire AIM CEA-IRFU/CNRS/Universite Paris Diderot Departement d'Astrophysique CEA Saclay F-91191 Gif sur Yvette France flash Center for Computational Science University of Chicago USA CEA DAM DIF F-91297 Arpajon France Clarendon Laboratory University of Oxford Parks Road Oxford OX1 3PU UK

the physics of compressible turbulence in high energy density(HED) plasmas is an unchartered experimental *** of compressible and radiative flows relevant for astrophysics rely mainly on subscale parameters. therefore,we plan to perform turbulent hydrodynamics experiments in HED plasmas(turboHEDP) in order to improve our understanding of such important phenomena for interest in both communities: laser plasma physics and astrophysics. We will focus on the physics of supernovae remnants which are complex structures subject to fluid instabilities such as the Rayleigh–taylor and kelvin–Helmholtz instabilities. the advent of megajoule laser facilities, like the National Ignition facility and the Laser Megajoule, creates novel opportunities in laboratory astrophysics, as it provides unique platforms to study turbulent mixing flows in HED plasmas. Indeed, the physics requires accelerating targets over larger distances and longer time periods than previously achieved. In a preparatory phase, scaling from experiments at lower laser energies is used to guarantee the performance of future MJ experiments. this subscale experiments allow us to develop experimental skills and numerical tools in this new field of research, and are stepping stones to achieve our objectives on larger laser facilities. We review first in this paper recent advances in high energy density experiments devoted to laboratory astrophysics. then we describe the necessary steps forward to commission an experimental platform devoted to turbulent hydrodynamics on a megajoule laser facility. Recent novel experimental results acquired on LULI2000, as well as supporting radiative hydrodynamics simulations, are presented. together with the development of Lif detectors as transformative X-ray diagnostics, these preliminary results are promising on the way to achieve micrometric spatial resolution in turbulent HED physics experiments in the near future.

关键词： high energy density physics inertial confinement fusion laboratory astrophysics plasmas astrophysics

精确测量功率MOSfEt的R_(DS(on))

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今日电子 2008年第11期 72-73页

作者： John t.Andrews 飞兆半导体公司

电阻值的测量通常比较简单。但是，对于非常小阻值的测量，我们必须谨慎对待我们所做的假定。对于特定的几何形状，如电线，kelvin方法是非常精确的。可以使用类似的方法来测量均匀样本的体电阻率和面电阻率，但是所使用的公式不同。在... 详细信息

电阻值的测量通常比较简单。但是，对于非常小阻值的测量，我们必须谨慎对待我们所做的假定。对于特定的几何形状，如电线，kelvin方法是非常精确的。可以使用类似的方法来测量均匀样本的体电阻率和面电阻率，但是所使用的公式不同。在这砦情况下，必须考虑探针间距和样本厚度。仅仅运用kelvin法本身无法保证精度。

关键词：精确测量功率MOSfEt RDS(on) 测试实验室测量值设备晶圆几何形状

Efficient mid-infrared single-photon detection using superconducting NbtiN nanowires with high time resolution in a Gifford-McMahon cryocooler

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Photonics Research 2022年第4期10卷 1063-1070页

作者： Jin chang Johannes W.N.Los Ronan Gourgues Stephan Steinhauer S.N.Dorenbos Silvania f.Pereira HPaul Urbach Val Zwiller Iman Esmaeil Zadeh Optics Research Group ImPhys DepartmentFaculty of Applied SciencesDelft University of TechnologyDelft 2628 CJThe Netherlands Single Quantum B.V. Delft 2628 CJThe Netherlands KtH Royal Institute of technology Department of Applied PhysicsAlbanova University Centre10691 StockholmSweden

Shortly after their inception, superconducting nanowire single-photon detectors(SNSPDs) became the leading quantum light detection technology. With the capability of detecting single-photons with near-unity efficiency,high time resolution, low dark count rate, and fast recovery time, SNSPDs outperform conventional single-photon detection techniques. However, detecting lower energy single photons(th high efficiency and low timing jitter has remained a challenge. to achieve unity internal efficiency at mid-infrared wavelengths, previous works used amorphous superconducting materials with low energy gaps at the expense of reduced time resolution(close to a nanosecond), and by operating them in complex milli kelvin(mK) dilution refrigerators. In this work,we provide an alternative approach with SNSPDs fabricated from 5 to 9.5 nm thick NbtiN superconducting films and devices operated in conventional Gifford-McMahon cryocoolers. By optimizing the superconducting film deposition process, film thickness, and nanowire design, our fiber-coupled devices achieved >70% system detection efficiency(SDE) at 2 μm and sub-15 ps timing jitter. furthermore, detectors from the same batch demonstrated unity internal detection efficiency at 3 μm and 80% internal efficiency at 4 μm, paving the road for an efficient mid-infrared single-photon detection technology with unparalleled time resolution and without mK cooling requirements. We also systematically studied the dark count rates(DCRs) of our detectors coupled to different types of mid-infrared optical fibers and blackbody radiation filters. this offers insight into the trade-off between bandwidth and DCRs for mid-infrared SNSPDs. to conclude, this paper significantly extends the working wavelength range for SNSPDs made from polycrystalline NbtiN to 1.5–4 μm, and we expect quantum optics experiments and applications in the mid-infrared range to benefit from this far-reaching technology.

关键词： nanowires technology SNSPD

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100MΩ范围内电阻比的测量

中国检验检测 1992年第4期 50-52页

作者： Andrew f.Dunn 沈怀诚

1.前言电阻比的测量,有赖于上述两种方法之一:对两个或多个串联电阻施加电流,并测量这些电阻端的电压比;或对每一对电阻施加已知比率的电流,直导每个电阻器上的端电压相同。经典的 Wheatstone 电桥及 kelvin 双电桥是运用第一种方法的实... 详细信息

1.前言电阻比的测量,有赖于上述两种方法之一:对两个或多个串联电阻施加电流,并测量这些电阻端的电压比;或对每一对电阻施加已知比率的电流,直导每个电阻器上的端电压相同。经典的 Wheatstone 电桥及 kelvin 双电桥是运用第一种方法的实例,而直流比例比较电桥则是运用第二种方法之实例。第一种方法是借

关键词：测量不确定度直流数字电压表检测器检测仪器电位计电位差计电阻比

Simulations on the Nonlinear Mode Coupling in Multiple-scale Drift-type turbulence with Coherent flow Structures

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Southwestern Institute of Physics Annual Report

Southwestern Institute of Physics Annual Report 2006年第1期 94-96页

作者： LI Jiquan Uzawa K. Lin Z. Kishimoto Y. Miyato N. Matsumoto t. DONG Jiaqi 不详 Graduate School of Energy Science Kyoto University 611-0011 Gokasho Uji Japan Department of Physics and Astronomy University of California Irvine California 92697 USA fusion Research and Development Directorate JAEA Naka Ibaraki 311-0193 Japan

1 Introduction Plasma fluctuations in magnetically confined devices, such as the magnetohydrodynamic （MHD） and drift-type turbulence in tokamaks, possess multiple spatio-temporal scales and spectral anisotropy and/or nonlinear instabilities. coexist and interplay each due to the richness of linear Multi-scale fluctuations may other in a highly turbulent environment so that the characteristics of individual turbulence may be affected, even changed. this important issue has attracted intensive attention recently. As an aspect of such problems, coherent zonal flow and low frequency long wavelength generalized kelvin-Helmholtz （GKH） fluctuations are generated nonlinearly as a secondary component.

关键词：非线性模式耦合漂流湍流流变力学

1979年夏季40—50天周期振荡的空间结构及其位相传播

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南京气象学院学报 1985年第1期8卷 56-66页

作者：何金海 Murakami t. Nakazawa 美国夏威夷大学气象系

本文根据fGGE Level Ⅲb资料详细分析了1979年夏季大范围内(30°S—30°N,30°E—150°W)40—50天周期振荡的空间分布及其传播特点。结果证实了早先关于“这些低频振荡主要表现为纬向风振荡”的究研结果,且它们向东向北传播。而季风区域... 详细信息

本文根据fGGE Level Ⅲb资料详细分析了1979年夏季大范围内(30°S—30°N,30°E—150°W)40—50天周期振荡的空间分布及其传播特点。结果证实了早先关于“这些低频振荡主要表现为纬向风振荡”的究研结果,且它们向东向北传播。而季风区域850毫巴经向风的振荡周期却小于10天,这或许反映了这一地区季风扰动的活跃。在赤道,40—50天周期的纬向风的扰动系统地向东(600公里/天)和向上(0.7公里/天)传播。纬向风、位势高度和大尺度的“视热源”场之间的位相关系表明这些扰动确实不象大气中的开尔文波。与赤道地区不同,沿着15°N的纬向风的位相虽然也向东传播但不很系统。在这一纬度,纬向风的振荡在季风地区是低层显著,而西太平洋地区是在高层显著。这两个系统的相互作用导致西风或东风在阿拉伯海地区向下传播。西风(东凤)向下的位相对应着南亚和东南亚地区季风活跃(中断)的开始。

关键词：毫巴西风位相周期振荡低层赤道地区东风向下传播垂直环流圈纬向风纬度剖面

Application of Micro-Electrochemical techniques in Corrosion Research

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Application of Micro-Electrochemical Techniques in Corrosion...