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Fabrication and absolute calibration of B-dot probe for magnetic field measurement on a high power laser facility 被引量:1
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作者 Longyu KUANG Feibiao XUE +10 位作者 Longfei JING Ruizhen YU Huabing DU Tao YI Tingshuai LI Hang LI Yi YU Feng WANG Shaoen JIANG Guangyue HU Jian ZHENG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第8期71-75,共5页
The fabrication and absolute calibration of a B-dot probe is employed to measure the pulsed magnetic field at the Shenguang-Ⅱhigh power laser facility.Copper enameled silk with a cross section diameter of 0.1 mm is u... The fabrication and absolute calibration of a B-dot probe is employed to measure the pulsed magnetic field at the Shenguang-Ⅱhigh power laser facility.Copper enameled silk with a cross section diameter of 0.1 mm is used to wind the one-turn coil with a 1 mm diameter.Two coils are paired and reversely linked to their respective circuits to form a differential B-dot probe that is sealed in and protected by a quartz shell.This B-dot probe is experimentally calibrated and then used to measure the pulsed magnetic field in laser targeting experiments at the Shenguang-Ⅱhigh power laser facility.Signals show a high performance of this B-dot probe.The common mode noise can be effectively canceled out by the differential pair.The magnetic field of over 300 T can be extrapolated at the location close to the target. 展开更多
关键词 b-dot MAGNETIC FIELD DIAGNOSTIC laser TARGETING
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New Evidence, Conditions, Instruments &Experiments for Gravitational Theories
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作者 Benjamin T. Solomon 《Journal of Modern Physics》 2013年第8期183-196,共14页
Two significant findings compel a rethink of physical theories. First, using a 7-billion-year-old gamma-ray burst, Nemiroff (2012) showed that quantum foam could not exists. And second, Solomon (2011) showed that grav... Two significant findings compel a rethink of physical theories. First, using a 7-billion-year-old gamma-ray burst, Nemiroff (2012) showed that quantum foam could not exists. And second, Solomon (2011) showed that gravitational acceleration is not associated with the gravitating mass, that gravitational acceleration g is determined solely by τ the change in time dilation over a specific height multiplied by c2 or g = τc2. Seeking consistency with Special Theory of Relativity, as means to initiate this rethink, this paper examines 12 inconsistencies in physical theories that manifest from empirical data. The purpose of this examination is to identify how gravitational theories need to change or be explored, to eliminate these 12 inconsistencies. It is then proposed that spacetime is much more sophisticated than just a 4-dimensional continuum. And, that the Universe consists of at least two layers or “kenos” (Greek for vacuous), the 4-dimensional kenos, spacetime (x, y, z, t) and the 3-dimensional kenos, subspace (x, y, z) that are joined at the space coordinates (x, y, z). This explains why electromagnetic waves are transverse, and how probabilities are implemented in Nature. This paper concludes by proposing two new instruments and one test, to facilitate research into gravitational fields, the new torsion-, tension- and stress-free near field gravity probe, the gravity wave telescope, and a non-locality test. 展开更多
关键词 RELATIVITY Special THEORY of RELATIVITY General THEORY of RELATIVITY Entanglement Baking Bread Transverse WAVE Electromagnetism Separation Vectors Gamma Ray Burst Quarks GRAVITY Modification Exotic Matter Photons Strings Shielding CLOAKING INVISIBILITY Near Field GRAVITY probe WAVE Function Gaussian
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大迎角细长体非对称空间流场特性的试验研究 被引量:13
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作者 顾蕴松 明晓 《实验流体力学》 CAS CSCD 北大核心 2005年第2期1-6,共6页
应用七孔探针定量流场测试技术,在低速风洞中通过定量测试细长旋成体背风区三维空间流场,研究了零侧滑条件下细长旋成体在典型大迎角情况下(迎角为55°)背风区附体和离体涡系的空间演化规律,加深了对细长旋成体背风区不对称涡系空... 应用七孔探针定量流场测试技术,在低速风洞中通过定量测试细长旋成体背风区三维空间流场,研究了零侧滑条件下细长旋成体在典型大迎角情况下(迎角为55°)背风区附体和离体涡系的空间演化规律,加深了对细长旋成体背风区不对称涡系空间结构的认识。解释了截面侧向力沿模型体轴分布为幅值递减波形的形成机制。给出了有、无头部小扰动片及小扰动片非定常摆动控制三种情况下的细长体背风区不同的多涡空间结构。细长旋成体背风区横截面的涡量和总压分布测量结果表明在模型头部固定小扰动片可以改变非对称涡的非对称特性,但不能使非对称涡变为对称涡,而在头部非定常小扰动的控制下模型背风区流动呈现对称涡的流态特征。 展开更多
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湖北钟祥累托石的电子显微研究 被引量:9
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作者 洪汉烈 铁丽云 +1 位作者 边秋娟 周泳 《电子显微学报》 CAS CSCD 2005年第2期124-128,共5页
利用扫描电镜、电子探针分析方法,对钟祥累托石的晶体形貌及化学成分特征进行了原位电子显微分析。结果表明,钟祥累托石普遍发育折叠状形态,一般可见有四种形式:波纹状、弯曲状、折曲状和扭折状。累托石晶体表面上常发育有多角形的台阶... 利用扫描电镜、电子探针分析方法,对钟祥累托石的晶体形貌及化学成分特征进行了原位电子显微分析。结果表明,钟祥累托石普遍发育折叠状形态,一般可见有四种形式:波纹状、弯曲状、折曲状和扭折状。累托石晶体表面上常发育有多角形的台阶,说明累托石晶体是通过一层一层的叠合生长方式而形成的;板片状的水云母晶体边缘转化形成薄片状、纤维状的累托石晶体,表明累托石晶体来源于云母的转化;纤维状、棒状的累托石晶体包裹于或穿插片状的累托石晶体,说明钟祥累托石经历了多期次的结晶作用。电子探针的分析结果表明,钟祥累托石的晶体化学式为:云母层(Na0.44K0.16)Al2[(AlSi3)O10](OH)2和蒙脱石层(Ca0.46Mg0.04Fe0.06)(Al1.76Fe0.10Ti0.14)[Al0.90Si3.10O10](OH)2·nH2O,是由钾、钠云母层和钙蒙脱石层规则间层而形成的一种混层矿物。 展开更多
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ArcGIS<sup>TM</sup>and Principal Component Analysis of Probe Data to Micro-Map Minerals in Round Top Rare Earth Deposit
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作者 Lorraine M. Negrón Margaret Piranian +2 位作者 Maria A. Amaya Daniel Gorski Nicholas E. Pingitore 《Advances in Materials Physics and Chemistry》 2020年第2期39-52,共14页
Rare earth elements (REEs), especially heavy rare earth elements (HREEs), are in demand for their current and emerging applications in advanced technologies. Here we perform computer-driven micro-mapping at the millim... Rare earth elements (REEs), especially heavy rare earth elements (HREEs), are in demand for their current and emerging applications in advanced technologies. Here we perform computer-driven micro-mapping at the millimeter scale of the minerals that comprise Round Top Mountain, in west Texas, USA. This large rhyolite deposit is enriched in HREEs and such other critical elements as Li, Be, and U. Electron probe microanalysis of 2 × 2 mm areas of thin sections of the rhyolite produced individual maps of 16 elements. These were superimposed to generate a 16-element composition at each pixel. Principal components analysis of elements at each pixel identified the specific mineral at that site. The pixels were then relabeled as the appropriate minerals, thereby producing a single mineral map. The overall mineral composition of the 7 studied samples compared favorably with prior analyses of the Round Top deposit available in the literature. Likewise the range of porosity in the maps was consistent with that of previous direct measurements by water saturation. This new statistical and GIS-based technique provides a robust and unbiased approach to electron microprobe mapping. The study further showed that the high-value yttrofluorite grains exhibited little tendency to cluster with other late-stage trace minerals and that the samples extended the previously documented overall homogeneity of the deposit at field scale to this microscopic scale. 展开更多
关键词 ArcGISTM Electron probe MICROANALYSIS Principal Component Analy-sis Rare Earths Yttrofluorite X-Ray MAP Analyzer ROUND TOP
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库尔勒香梨的苹果褪绿叶斑病毒cDNA探针检测技术研究 被引量:1
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作者 牛建新 朱军 马兵钢 《西北农业学报》 CAS CSCD 北大核心 2005年第2期58-63,共6页
以库尔勒香梨叶片和皮层为材料,对两种植物总RNA提取方法进行了比较研究,从中筛选出了适合库尔勒香梨的提取方法;并利用RT-PCR反应体系成功合成了生物素标记的cDNA探针,在此基础上,对影响杂交灵敏度的主要因素进行了实验研究。结果表明... 以库尔勒香梨叶片和皮层为材料,对两种植物总RNA提取方法进行了比较研究,从中筛选出了适合库尔勒香梨的提取方法;并利用RT-PCR反应体系成功合成了生物素标记的cDNA探针,在此基础上,对影响杂交灵敏度的主要因素进行了实验研究。结果表明,当探针浓度为400ng/mL,甲酰胺浓度为45%,42℃杂交反应6h,可获得最高灵敏度。Tween20的封闭效果比牛血清白蛋白好。对不同组织和不同提取方法提取的总RNA进行了杂交检测,并对库尔勒地区香梨带毒情况进行了检测。结果表明,不论幼叶、老叶、皮层及冷冻叶片均可出现杂交信号,两种提取方法提取的总RNA也都出现了杂交信号,库尔勒香梨样品有45%的带苹果褪绿叶斑病毒。 展开更多
关键词 绿 CDNA RNA PCR Tween20 RNA
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Correlation of work function and stacking fault energy through Kelvin probe force microscopy and nanohardness in diluteα-magnesium
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作者 Yigit Türe Ali Arslan Kaya +2 位作者 Hüseyin Aydin Jiang Peng Servet Turan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期237-250,共14页
Electronic interactions of the Group 2A elements with magnesium have been studied through the dilute solid solutions in binary Mg-Ca,Mg-Sr and Mg-Ba systems.This investigation incorporated the difference in the‘Work ... Electronic interactions of the Group 2A elements with magnesium have been studied through the dilute solid solutions in binary Mg-Ca,Mg-Sr and Mg-Ba systems.This investigation incorporated the difference in the‘Work Function'(ΔWF)measured via Kelvin Probe Force Microscopy(KPFM),as a property directly affected by interatomic bond types,i.e.the electronic structure,nanoindentation measurements,and Stacking Fault Energy values reported in the literature.It was shown that the nano-hardness of the solid-solutionα-Mg phase changed in the order of Mg-Ca>Mg-Sr>Mg-Ba.Thus,it was shown,by also considering the nano-hardness levels,that SFE of a solid-solution is closely correlated with its‘Work Function'level.Nano-hardness measurements on the eutectics andΔWF difference between eutectic phases enabled an assessment of the relative bond strength and the pertinent electronic structures of the eutectics in the three alloys.Correlation withΔWF and at least qualitative verification of those computed SFE values with some experimental measurement techniques were considered important as those computational methods are based on zero Kelvin degree,relatively simple atomic models and a number of assumptions.As asserted by this investigation,if the results of measurement techniques can be qualitatively correlated with those of the computational methods,it can be possible to evaluate the electronic structures in alloys,starting from binary systems,going to ternary and then multi-elemental systems.Our investigation has shown that such a qualitative correlation is possible.After all,the SFE values are not treated as absolute values but rather become essential in comparative investigations when assessing the influences of alloying elements at a fundamental level,that is,free electron density distributions.Our study indicated that the principles of‘electronic metallurgy'in developing multi-elemental alloy systems can be followed via practical experimental methods,i.e.ΔWF measurements using KPFM and nanoindentation. 展开更多
关键词 Mg alloys Dilute alloys Work function Stacking fault energy Kelvin probe force microscopy Short range order Miedema NANOINDENTATION EUTECTICS
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A Study of Design Optimization Using Response Surface Analysis and Fabricaiton MEMS Probe Tip
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作者 K. B. Kim J. W. Lee +2 位作者 S. J. Ha Y. K. Cho M. W. Cho 《Journal of Applied Mathematics and Physics》 2015年第2期201-207,共7页
In semiconductor manufacturing process, probe station that is testing equipment is important. Inspection step is for detecting defects on semiconductor before the packaging. Probe card is a part of probe station and c... In semiconductor manufacturing process, probe station that is testing equipment is important. Inspection step is for detecting defects on semiconductor before the packaging. Probe card is a part of probe station and contains probe tip that contacts to semiconductor. Through probe tip, it can inspect defects of semiconductor. In this paper, optimization method is used with response surface analysis to design MEMS type probe tip. And fabricating probe tip uses maskless lithography, electro-plating and lapping process. 展开更多
关键词 A STUDY of Design Optimization USING RESPONSE Surface Analysis and Fabricaiton MEMS probe TIP
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A First Principles Simulation Framework for the Interactions between a Si(001) Surface and a Scanning Probe
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作者 Dung Q. Ly Charalampos Makatsoris 《Journal of Surface Engineered Materials and Advanced Technology》 2012年第3期194-202,共9页
By means of total energy calculations within the framework of the local density approximation (LDA), the interactions between a silicon Si(001) surface and a scanning probe are investigated. The tip of the probe, comp... By means of total energy calculations within the framework of the local density approximation (LDA), the interactions between a silicon Si(001) surface and a scanning probe are investigated. The tip of the probe, comprising 4 Si atoms scans along the dimer lines above an asymmetric p(2 × 1) surface, at a distance where the chemical interaction between tip-surface is dominant and responsible for image resolution. At that distance, the tip causes the dimer to toggle when it scans above the lower atom of a dimer. The toggled dimers create an alternating pattern, where the immediately adjacent neighbours of a toggled dimer remain unchanged. After the tip has fully scanned across the p(2 × 1) surface, causes the dimers to arrange in a p(2 × 2) reconstruction, reproducing the images obtained in scanning probe experiments. Our modelling methodology includes simulations that reveal the energy input required to overcome the barrier to the onset of dimer toggling. The results show that the energy input to overcome this barrier is lower for the p(2 × 1) surface than that for the p(2 × 2) or c(4 × 2) surfaces. 展开更多
关键词 DFT Si(001)-p(2 × 1) p(2 × 2) c(4 × 2) Scanning probe Microscopy Phase TRANSITIONS DIMER Toggling
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地高辛标记探针检测猪胸膜肺炎放线杆菌的研究与应用 被引量:9
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作者 刁有祥 丁家波 +3 位作者 姜世金 孙淑红 崔治中 陈本龙 《畜牧兽医学报》 CAS CSCD 北大核心 2005年第6期585-589,共5页
利用PCR反应扩增出胸膜肺炎放线杆菌ApxⅣ基因650 bp的DNA,回收并纯化PCR产物,用地高辛标记,制备出地高辛标记的核酸探针。该探针与不同血清型的胸膜肺炎放线杆菌均能发生特异性杂交,而与大肠杆菌、多杀性巴氏杆菌、沙门氏菌、葡萄球菌... 利用PCR反应扩增出胸膜肺炎放线杆菌ApxⅣ基因650 bp的DNA,回收并纯化PCR产物,用地高辛标记,制备出地高辛标记的核酸探针。该探针与不同血清型的胸膜肺炎放线杆菌均能发生特异性杂交,而与大肠杆菌、多杀性巴氏杆菌、沙门氏菌、葡萄球菌、猪肺炎支原体、支气管败血波氏杆菌等细菌的核酸杂交均为阴性。对胸膜肺炎放线杆菌的最低检出限量为10×102 个放线杆菌。对疑似胸膜肺炎放线杆菌感染病变组织检测结果表明,在扁桃体、鼻腔、气管、肺脏均可检测出胸膜肺炎放线杆菌,以扁桃体的检出率最高。为猪胸膜肺炎放线杆菌的诊断和流行病学调查提供了良好的方法。 展开更多
关键词 线 PCR PCR DNA APX
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Dynamic NMR and Twisted Intramolecular Charge Transfer Excited States
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作者 Iraj Parchamazad Debra Hornyak Melvin Miles 《American Journal of Analytical Chemistry》 2015年第5期402-410,共9页
In this paper the results of dynamic NMR studies on ethylmethylamino-tertiary-butyl-phenylborane (EMABPB) with or without light are reported. The NMR data were recorded on a Bruker 400 MHz NMR equipped with our custom... In this paper the results of dynamic NMR studies on ethylmethylamino-tertiary-butyl-phenylborane (EMABPB) with or without light are reported. The NMR data were recorded on a Bruker 400 MHz NMR equipped with our custom-made optical probe and with our custom-made 450 watts (W) monochromatic light sources. The molecular photochemistry including twisted intramolecular charge-transfer-excited-state (TICT) of the EMABPB in several solvents has been investigated. These results indicate that the aminoborane demonstrates multiple configurations in CD3Cl and CD2Cl2 resulting in the shifts of the signals of the alkyl groups on the nitrogen and boron. This indicates that there are some time-dependent changes at constant temperature over the irradiation interval. At ﹣60&deg;C and the presence of light (λ = 265 nm), we observed a large change in the populations of the two sites, and this by itself indicates a modification in the rotation around the boron nitrogen bond in the excited state. By considering the existence of the TICT state, many important energy technologies may be developed with higher efficiency by controlling the back-electron transfer processes. 展开更多
关键词 TWISTED Intramolecular Charge TRANSFER STATE Back Electron TRANSFER TWISTED Excited STATE Dynamic NMR Rotation around B-N Bond Molecular PHOTOCHEMISTRY inside NMR probe Customized Optical probe Solvent Effect Low Temperature Spectra
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三维原子探针——从探测逐个原子来研究材料的分析仪器 被引量:11
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作者 周邦新 《自然杂志》 北大核心 2005年第3期125-129,共5页
材料是科学技术和国民经济发展的重要基础,研究和开发先进材料,满足科学技术发展的要求,是材料研究工作者的永恒主题。材料的成分和加工工艺,决定了材料的显微组织,而材料的性能又与显微组织有着密切的关系。因此,研究材料的显微组织是... 材料是科学技术和国民经济发展的重要基础,研究和开发先进材料,满足科学技术发展的要求,是材料研究工作者的永恒主题。材料的成分和加工工艺,决定了材料的显微组织,而材料的性能又与显微组织有着密切的关系。因此,研究材料的显微组织是研究开发先进材料的工作基础,而充分并正确利用现代的各种分析仪器,是研究显微组织的关键。本文介绍了一种能够分析逐个原子的仪器——三维原子探针,用这种仪器可以了解金属材料中不同合金元素在微区中不均匀分布的问题;可以了解合金元素在各种界面及晶体缺陷处的偏聚分布;可以了解显微组织变化初期时只有数十个不同原子发生团聚时的过程。三维原子探针是目前最微观的分析仪器,能够进行成分的定量分析,在研究金属材料的许多问题时都可以发挥重要的作用。 展开更多
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Probe Selection for Over-the-Air Test in 5G Base Stations with Massive Multiple-Input Multiple-Output 被引量:3
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作者 Xiang Zhang Shangbin Qiao +1 位作者 Mugen Peng Yong Li 《China Communications》 SCIE CSCD 2019年第7期1-12,共12页
In 5G systems, massive multiple-input multiple-output (MIMO) has been adopted in base stations (BSs) to improve spectral efficiency and coverage. The traditional conductive performance test techniques are challenging ... In 5G systems, massive multiple-input multiple-output (MIMO) has been adopted in base stations (BSs) to improve spectral efficiency and coverage. The traditional conductive performance test techniques are challenging due to the unaffordable cost and high complexity when testing a large number of antennas. To solve this problem, the over-the-air (OTA) test has been presented, in which probe selection is the key to reduce the number of channel emulators and probes. In this paper, a novel artificial bee colony (ABC) algorithm is introduced to enhance the efficiency and accuracy of probe selection procedure. A sectoring- based multi-probe anechoic chamber (MPAC) is built to evaluate the throughput performance of massive MIMO equipped in 5G BS. In addition, link level simulation is carried out to evaluate the proposal’s performance gain under the commercial network assumptions, where the average throughput of three velocity is given with different SNR region. The results suggest that OTA chamber and multi-probe wall are available not only for 5G BSs, but also for user equipments (UEs) with end-to-end communication. 展开更多
关键词 anechoic chamber MASSIVE MIMO base stations over-the-air TEST probe SELECTION performance evaluation
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Molecular Probes in Tandem Electrospray Ionization Mass Spectrometry: Application to Tracing Chemical Changes of Specific Phospholipid Molecular Species
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作者 Hiroko Tominaga Tomoe Ishihara +8 位作者 A. K. M. Azad Shah Rumiko Shimizu Arnold N. Onyango Hideyuki Ito Toshinori Suzuki Yasuhiro Kondo Hiroshi Koaze Koretaro Takahashi Naomichi Baba 《American Journal of Analytical Chemistry》 2013年第10期16-26,共11页
New ionization and detection techniques in mass spectrometry have been successfully applied for efficient analyses of complex biological systems. It is, however, still difficult to trace structural changes of a specif... New ionization and detection techniques in mass spectrometry have been successfully applied for efficient analyses of complex biological systems. It is, however, still difficult to trace structural changes of a specific molecular species in such systems. In the present study, a molecular probe strategy in combination with tandem electrospray ionization mass spectrometry has been examined using synthetic deuterium-labeled phosphatidylcholine hydroperoxide (PC-OOH/D3) and ethyl-labeled phosphatidylcholine having docosahexaenoic acid side chain (DHA-PC/Et). Administration of a mixture of PC-OOH/D3 and DHA-PC/Et to human blood and human skin surface, followed by extraction and analysis with collision-induced tandem electrospray ionization mass spectrometry demonstrated that metabolites of both molecular probes can be detected simultaneously with strict selectivity. The present method is also found to be useful in tracing chemical changes of the unstable docosahexaenoyl group on the surface of processed fish. The activity of phospholipase A2 can also be assessed using a phospholipid molecular probe with a linoleoyl and a deuteriomethyl group via selective detection of the lyso-phospholipid product by mass spectrometry. The advantage of the present method is that no chromatographic separation is required and analysis can be performed under strictly the same condition for different molecular probes, affording multiple data by one experiment. The present strategy may be useful for tracing time-dependent phenomena in dynamic phospholipid biochemistry, and can be widely used for any biological and food systems. 展开更多
关键词 Molecular probe Stable ISOTOPE Mass Spectrometry ELECTROSPRAY Ionization LIPID PEROXIDATION LIPID Oxidation Skin Surface
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Lipid-Protein Microinclusions in the Morphological Structures of Organelle Membranes Studied by Fluorescent Confocal Microscopy
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作者 Michael Yu. Chernyshov Vadim N. Nurminsky Natalia V. Ozolina 《Advances in Biological Chemistry》 2017年第1期42-59,共18页
Peculiar properties of morphological structures of organelle membranes were studied by fluorescent confocal microscopy. The list of objects in our experiments was represented by mitochondria, chloroplasts and vacuoles... Peculiar properties of morphological structures of organelle membranes were studied by fluorescent confocal microscopy. The list of objects in our experiments was represented by mitochondria, chloroplasts and vacuoles. During this study, identification of lipid microinclusions having the form of such lipid-protein structural microformations as lipid-protein microdomains, vesicles and membrane tubular structures (cytoplasmic transvacuolar strands and nanotubes) located in organelle membranes or bound up with them was conducted. Such membrane probes as laurdan, DPH, ANS and bis-ANS were used. Comparison of fluorescence intensity of these membrane probes was conducted. This investigation of the morphological properties of lipid-protein structural microformations was accompanied with analysis of 1) the phase state and 2) dynamics of microviscosity variations in the membrane elements of isolated plant cell organelles. Distributions of laurdan fluorescence generalized polarization (GP) values for the membrane on the whole and for the intensively fluorescing membrane segments were obtained. It was discovered that the microviscosity of intensively fluorescing membrane segments essentially differed from the microviscosity of the rest part of the membrane. In conclusion, some results of the study of peculiar properties of lipid-protein structural microformations related to the structure of organelle membranes and the discoveries made in this investigation are discussed. 展开更多
关键词 Identification of Lipids MORPHOLOGICAL Structure of Cell Organelles MORPHOLOGICAL Structure of Vacuolar MEMBRANE FLUORESCENT Confocal Microscopy FLUORESCENT probes Lipid-Protein Structural MEMBRANE Microinclusions Types of Microformations Identified Lipid-Protein Microdomains Lipid-Protein MEMBRANE Nanotubes Vesicles Cytoplasmic Strands MICROVISCOSITY
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PCR和核酸探针检测猪源沙门氏菌四环素耐药基因tetC的研究 被引量:15
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作者 代敏 王红宁 吴琦 《畜牧兽医学报》 CAS CSCD 北大核心 2005年第5期482-485,共4页
对沙门氏菌的四环素耐药性进行了检测,结果表明,沙门氏菌对四环素类抗生素产生了广泛的耐药性,耐药率达100%,对其四环素耐药基因tetC进行了扩增,结果获得以质粒为模板的特异性产物,与药敏试验结果阳性符合率75%,具有较高的检出率。用光... 对沙门氏菌的四环素耐药性进行了检测,结果表明,沙门氏菌对四环素类抗生素产生了广泛的耐药性,耐药率达100%,对其四环素耐药基因tetC进行了扩增,结果获得以质粒为模板的特异性产物,与药敏试验结果阳性符合率75%,具有较高的检出率。用光生物素对PCR产物进行标记,制备核酸探针,采用菌落原位杂交的方法对沙门氏菌进行检测,结果表明13株阳性、3株阴性,杂交结果与PCR结果阳性符合率为93.75%,具有较高的特异性。通过条件的优化,建立的四环素耐药基因tetC的PCR和核酸探针检测技术,为四环素耐药性的分子流行病学监测提供了有效的途径。 展开更多
关键词 TETC PCR PCR
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Zemax-Based Optimum Structural Design of Probe of an Optical-Fiber Sensor 被引量:1
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作者 Hang Tianyuan Wang Xiaolei +2 位作者 Liu Feng Ye Song Chen Zhentao 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第2期309-317,共9页
Bubble plumes are important during the process of air-sea exchange,and optical-fiber phase detection is a suitable way to observe bubble plumes entrained by breaking waves.This paper designs a new optical-fiber probe(... Bubble plumes are important during the process of air-sea exchange,and optical-fiber phase detection is a suitable way to observe bubble plumes entrained by breaking waves.This paper designs a new optical-fiber probe(OFP)made of sapphire to overcome the limitations of existing materials(e.g.,high brittleness,poor corrosion resistance,and narrow bandwidth)and thereby enhance the detection performance of the OFP by improving its structure.Based on total internal reflection and light refraction,a simulation model of the probe is established in the Zemax optical design software to optimize the probe tip and matching mode of the two probe tips.The results show that the optimum OFP tip is a conical sapphire one with a cone angle of 35°.Tests are then conducted on a bespoke OFP sensor,the results of which are consistent with those predicted theoretically.The simulation results lay the foundation for the integrated design of OFP sensors and the optimization of their internal optics.The findings could also be applied to OFPs with multiple tips. 展开更多
关键词 BUBBLE measurement OPTICAL-FIBER probe OPTIMUM design light transmission test ZEMAX OPTICAL simulation
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Radix Polygoni Multiflori Praeparata and Dioscorea Bulbifera Rhizome Decoctions Display Combined Effects Detected by a Three-Probe Drug Cocktail with Substrates of Rat Hepatic Cytochrome P450 Enzymes
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作者 Li Jiang Pingping Shan +3 位作者 Hui Yu Jiayuan Tao Chunyan Gong Guoqing Shen 《Pharmacology & Pharmacy》 2014年第7期736-746,共11页
Objectives: Radix Polygoni Multiflori Praeparata (RPMP) and Dioscorea Bulbifera Rhizomes (DBR) are used in Chinese herbal medicine and have been frequently reported for adverse reactions on liver. In this research, we... Objectives: Radix Polygoni Multiflori Praeparata (RPMP) and Dioscorea Bulbifera Rhizomes (DBR) are used in Chinese herbal medicine and have been frequently reported for adverse reactions on liver. In this research, we aimed to evaluate in vivo effects of RPMP and DBR on rat cytochrome P450 enzymes (CYP1A2, CYP2E1 and CYP3A2) with their respective substrates as probes. Methods: Rats were orally administered RPMP, DBR and RPMP/DBR combination at 12, 10 and (12 + 10) g/kg, respectively, or saline as a control, once daily for 7 days. Thereafter, a cocktail containing 10 mg/kg caffeine, 20 mg/kg chlorzoxazone and 10 mg/kg dapsone was tail vein injected to rats. At defined time points, plasma drug concentrations were simultaneously evaluated by HPLC. Pharmacokinetic parameters simulated by DAS software were used to assess RPMP and/or DBR effects on cytochrome P450 enzymes activity. ANOVA and Dunnett’s test were used for data analysis. Results: Caffeine metabolism was enhanced in RPMP animals and reduced after pretreatment with DBR, but no effect was observed in RPMP/DBR combination group. Chlorzoxazone and dapsone metabolism was enhanced in both RPMP and DBR groups and consequently in combination group. The data suggested that RPMP independently induces rat CYP1A2, CYP2E1 and CYP3A2 activity, while DBR independently inhibits activity of rat CYP1A2 and induces that of CYP2E1 and CYP3A2. RPMP/DBR combination showed no significant benefit compared with the two drugs alone and even showed a neutralized effect in CYP1A2 activity. Conclusions: Caution is needed when RPMP and/or DBR are co-administered with drugs metabolized by human CYP1A2, CYP2E1 and CYP3A4. 展开更多
关键词 RADIX Polygoni Multiflori Praeparata DIOSCOREA Bulbifera Rhizomes Cytochrome P450 Herb-Drug Interactions Three-probe DRUG COCKTAIL
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信息处理板综合测试系统设计 被引量:1
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作者 王刚 王跃科 王大明 《计算机测量与控制》 CSCD 2005年第3期229-231,共3页
为实现某型信息处理板的验收测试和提供科研调试的技术支持, 该信息处理板综合测试系统采用了以工控机为基础的虚拟仪器系统设计方案, 基于开放式自动测试系统体系结构的要求, 配合各仪器子模块、继电器阵列、专用测试夹具和程控电源, ... 为实现某型信息处理板的验收测试和提供科研调试的技术支持, 该信息处理板综合测试系统采用了以工控机为基础的虚拟仪器系统设计方案, 基于开放式自动测试系统体系结构的要求, 配合各仪器子模块、继电器阵列、专用测试夹具和程控电源, 在LAB VIEW及其工具包的协调下实现了产品验收的自动测试, 并通过设计的一套" DSP软件探针" 对科研人员的程序调试提供了技术支持。 展开更多
关键词 DSP
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译者主体性意识的语用透视 被引量:2
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作者 李占喜 《北京第二外国语学院学报》 2010年第12期1-7,共7页
本文从关联理论和顺应理论的语用学视角对译者的主体性意识赋予了新的语用含意,并对翻译过程中译者的主体性意识进行了语用透视。笔者认为:译者客观、不偏不倚的翻译态度将会对其译文选择具有重要作用;在语篇释意交际过程中,译者读者和... 本文从关联理论和顺应理论的语用学视角对译者的主体性意识赋予了新的语用含意,并对翻译过程中译者的主体性意识进行了语用透视。笔者认为:译者客观、不偏不倚的翻译态度将会对其译文选择具有重要作用;在语篇释意交际过程中,译者读者和研究者身份的"介入"使其调动其现有的认知资源,解读出与作者交际意图相匹配的最佳关联;在语篇产出交际过程中,译者的作者替身、再创造者、协调者身份的"介入",在最佳关联的引导下进行语言选择,以确保译文读者认知和谐的方式,达到跨文化交际的成功实现。 展开更多
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