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Characterization of a Microhollow Cathode Discharge Plasma in Helium or Air with Water Vapor 被引量:2
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作者 D. FUKUHARA S. NAMBA +2 位作者 K. KOZUE T. YAMASAKI K. TAKIYAMA 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第2期129-132,共4页
Microhollow cathode discharge (MHCD) plasmas were generated in gas mixtures containing water vapor at pressures of up to 100 kPa of He or 20 kPa of air. The cathode diameter was 1.0 mm with a length of 2.0 ram. The ... Microhollow cathode discharge (MHCD) plasmas were generated in gas mixtures containing water vapor at pressures of up to 100 kPa of He or 20 kPa of air. The cathode diameter was 1.0 mm with a length of 2.0 ram. The electricM characteristics showed an abnormal glow mode. Spectroscopic measurements were carried out to examine the plasma and radicals. An analysis of the spectral profile of Ha at 656.3 nm enabled a derivation of the electron densities, namely 2× 1014 cm-3 (at 10 kPa) and 6× 1014 cm-3 (at 4 kPa) for the helium and air atmospheres, respectively, in the negative glow region. By comparing the observed OH radical spectra with those calculated by the simulation code L[FBASE, the gas temperature was deduced to be 900 K for 4 kPa of He at a discharge current of 50 mA. 展开更多
关键词 microhollow cathode discharge atmospheric pressure plasma plasma spec-troscopy
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Femtosecond laser user facility for application research on ultrafast science 被引量:1
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作者 Zhaohua Wang Shaobo Fang +3 位作者 Hao Teng Hainian Han Xinkui He Zhiyi Wei 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第7期66-71,共6页
The advent of chirped-pulse amplification (CPA) has greatly advanced the field of ultrafast and ultra-intense laser technology. CPA has become an indispensable platform for multidisciplinary research, such as physic... The advent of chirped-pulse amplification (CPA) has greatly advanced the field of ultrafast and ultra-intense laser technology. CPA has become an indispensable platform for multidisciplinary research, such as physics, chemistry, life sciences, and precision metrology. The femtosecond laser facility at the Synergic Extreme Condition User Facility (SECUF) is a comprehensive experimental platform with an advanced femtosecond laser source for ultrafast scientific research. It will provide an ultrafast scientific research system having a few-cycle pulse duration, wide spectral range, high energy, and high repetition rate for multipurpose applications. 展开更多
关键词 FEMTOSECOND carrier envelope phase (CEP) chirped-pulse amplification (CPA) ultrafast spec-troscopy optical parametric amplifier (OPA)
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A double toroidal analyzer for scanning probe electron energy spectrometer 被引量:1
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作者 徐春凯 张盼科 +1 位作者 郦盟 陈向军 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期183-187,共5页
An ultra-high vacuum (UHV) compatible electron spectrometer employing a double toroidal analyzer has been de- veloped. It is designed to be combined with a custom-made scanning tunneling microscope (STM) to study ... An ultra-high vacuum (UHV) compatible electron spectrometer employing a double toroidal analyzer has been de- veloped. It is designed to be combined with a custom-made scanning tunneling microscope (STM) to study the spatially localized electron energy spectrum on a surface. A tip-sample system composed of a piezo-driven field-emission tungsten tip and a sample of highly ordered pyrolytic graphite (HOPG) is employed to test the performance of the spectrometer. Two-dimensional images of the energy-resolved and angle-dispersed electrons backscattered from the surface of HOPG are obtained, the performance is optimized and the spectrometer is calibrated. A complete electron energy loss spectrum covering the elastic peak to the secondary electron peaks for the HOPG surface, acquired at a tip voltage of -140 V and a sample current of 0.5 pA, is presented, demonstrating the viability of the spectrometer. 展开更多
关键词 double toroidal analyzer scanning probe electron energy spectroscopy electron energy loss spec-troscopy secondary electron emission spectroscopy
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Excitation energy transfer mechanisms in allophycocyanin(Ⅰ)——Energy transfer mechanisms in monomer 被引量:1
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作者 ZHANG Jingmin, ZHENG Xiguang, ZHAO Fuli, WANG Hezhou, ZHANG Jianping, ZHAO Jingquan and JIANG Lijin State Key Laboratory for Ultrafast Laser Spectroscopy, Zhongshan University, Guangzhou 510275, China Institute of Photographic Chemistry , Chinese Academy of Sciences , Beijing 100101, China 《Chinese Science Bulletin》 SCIE EI CAS 1999年第11期1003-1008,共6页
The mechanisms of excitation energy transfer within allophycocyanin monomer with the theory of generalized master equation (GME) and the technique of time-resolved fluorescence anisotropic spectroscopy are studied. In... The mechanisms of excitation energy transfer within allophycocyanin monomer with the theory of generalized master equation (GME) and the technique of time-resolved fluorescence anisotropic spectroscopy are studied. In the case of known information of its structure and spectra, the theory applied is based on the assumption that the coupling interaction between two chromophores is fairly weak. The theory correctly predicts the experimentlly observed rate for excitation energy transfer in allophycocyanin monomer. Based on the results, the energy transfer mechanism can be described as Frster and these processes cannot take place from the high vibrational levels of donor to acceptor. 展开更多
关键词 ALLOPHYCOCYANIN energy transfer generalized MASTER equation TIME-RESOLVED fluorescence ANISOTROPIC spec-troscopy.
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Plasma Diagnosis for Microwave ECR Plasma Enhanced Sputtering Deposition of DLC Films
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作者 庞见华 陆文琪 +3 位作者 辛煜 王行行 贺佳 徐军 《Plasma Science and Technology》 SCIE EI CAS CSCD 2012年第2期172-176,共5页
Application of the Langmuir probe in plasma circumstance for deposition of diamond-like carbon (DLC) thin films usually faces the problem of rapid failure of the probe due to surface insulative coating. In this pape... Application of the Langmuir probe in plasma circumstance for deposition of diamond-like carbon (DLC) thin films usually faces the problem of rapid failure of the probe due to surface insulative coating. In this paper, we circumvent the problem by using the floating harmonic probe technique. In the real circumstance of DLC film deposition, the floating harmonic probe worked reliably over 3 hours, correctly indicating the ion density and electron temperature. The technique was practically used to measure the ion density and electron temperature in DLC film deposition processes using the microwave ECR plasma enhanced sputtering. Combined with the Raman spectroscopic characterization of the films, the conditions for deposition of DLC films were investigated. 展开更多
关键词 floating harmonic probe DLC films microwave ECR plasma Raman spec-troscopy
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Experimental studies of N^+ implantation into CVD diamond thin films
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作者 辛火平 林成鲁 +5 位作者 王建新 邹世昌 石晓红 林梓鑫 周祖尧 刘祖刚 《Science China(Technological Sciences)》 SCIE EI CAS 1997年第4期361-368,共8页
The effects of N+ implantation under various conditions on CVD diamond films were analyzed with Raman spectroscopy, four-point probe method, X-ray diffraction (XRD), Rutherford backseattering spectroscopy (RBS), ultra... The effects of N+ implantation under various conditions on CVD diamond films were analyzed with Raman spectroscopy, four-point probe method, X-ray diffraction (XRD), Rutherford backseattering spectroscopy (RBS), ultraviolet photoluminescence spectroscopy (UV-PL), Fourier transformation infrared absorption spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The results show that the N+ implantation doping without any graphitization has been successfully realized when 100 keV N+ ions at a dosage of 2 × 1016 cm-2 were implanted into diamond films at 550℃ . UV-PL spectra indicate that the implanted N+ ions formed an electrically inactive deep-level impurity in diamond films. So the sheet resistance of the sample after N+ implantation changed little. Carbon nitride containing C≡N covalent bond has been successfully synthesized by 100 keV, 1.2×1018 N/cm2 N+ implantation into diamond films. Most of the implanted N+ ions formed C≡N covalent bonds with C atoms. The others were free state nitrogen, which existed in the excessive nitrogen layers. C(1s) XPS studies show the existence of three different C(1s) bonding states, corresponding to graphite, i-carbon and the carbon of C≡N covalent bonding state, respectively, which agrees well with the Raman results. 展开更多
关键词 N+ IMPLANTATION into diamond films Raman spectroscopy ultraviolet photoluminescence spec-troscopy (UV-PL) electrically inactive deep-level IMPURITY C≡N COVALENT bond carbon nitride X-ray photoelec-tron spectroscopy (XPS). N+ IMPLANTATION
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Synchronous fluorescence technique and its use in identification of polynuclear aromatic hydrocarbons in urine samples
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作者 Zhao Zhenhua and Quan Wenyi Beijing Municipal Research Insitute of Environmental Protection 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1989年第2期109-115,共7页
The synchronous fluorescence spectroscopy of three polymiclear aromatic hydrocarbons was studied. It was shown that the specific Δλ of the spectra were 10nm for benzo(k) fluoranthene, 25 nm for benzo(a) pyrene, and ... The synchronous fluorescence spectroscopy of three polymiclear aromatic hydrocarbons was studied. It was shown that the specific Δλ of the spectra were 10nm for benzo(k) fluoranthene, 25 nm for benzo(a) pyrene, and 40 nm for pyrene. The peaks of the spectra were at 407, 404, and 373 nm for the three chemicals, respectively. Benzo(k) fluoranthene, benzo(a) pyrene, and pyrene in the urine samples from smokers were identified by high pressure liquid chromatography combined with the synchronous fluorescence spectroscopy. 展开更多
关键词 polynuclear aromatic hydrocarbons synchronous fluorescence spec-troscopy urine.
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Thermal Behavior and Crystal Transition of Biodegradable Poly(butylenes adipate)Revealed by Two-Dimensional Correlation Spectroscopy
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作者 CHEN Yu-jing Isao Noda Young Mee Jung 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2016年第S1期139-140,共2页
In the present study,thermal behavior and crystal transition of pure poly(butylene adipate)(PBA)upon heating process were investigated by FTIR spectroscopy.To gain further insight into the thermal behavior alteration ... In the present study,thermal behavior and crystal transition of pure poly(butylene adipate)(PBA)upon heating process were investigated by FTIR spectroscopy.To gain further insight into the thermal behavior alteration and the phase transition of PBA,we performed two-dimensional(2D)correlation analysis.We found thatβ-form PBA crystal undergoes not only the melting process but also crystal transition upon the heating process. 展开更多
关键词 Poly(butylene adipate) Thermal behavior Crystal transition Two-dimensional correlation spec-troscopy
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“钻石钥匙”开启单分子磁共振研究之门 被引量:2
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作者 张琪 石发展 杜江峰 《物理》 CAS 北大核心 2015年第9期565-575,共11页
近半个世纪以来,快速涌现和发展的单分子技术使人们对微观世界的认知甚至调控能力得到前所未有的深化和提高。磁共振技术在获取物质的组成和结构信息方面,拥有准确、快速和无破坏性的独特优势,已广泛应用于物理、化学、材料和生物医学... 近半个世纪以来,快速涌现和发展的单分子技术使人们对微观世界的认知甚至调控能力得到前所未有的深化和提高。磁共振技术在获取物质的组成和结构信息方面,拥有准确、快速和无破坏性的独特优势,已广泛应用于物理、化学、材料和生物医学等领域。当前通用的磁共振技术通常仅能得到数十亿个分子的统计平均信息,将其灵敏度推进到单分子水平一直是磁共振领域最重要的课题之一,但实现这一目标面临诸多挑战。最新的研究进展表明,基于金刚石的新型磁共振技术能将研究对象推进到单分子,成像分辨率从原来的毫米级提升至纳米级。文章介绍了单分子磁共振研究的发展脉络和最新进展,并展望了今后的发展方向。 展开更多
关键词 金刚石 氮-空位缺陷 单分子磁共振 谱学 成像
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Neuroprotective effect of Naomaitong extract following focal cerebral ischemia induced by middle cerebral artery occlusion in rats 被引量:1
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作者 Yang Yongxia Chen Xi +3 位作者 Wang Shumei Wang Zhanhong Li Jiansheng Liang Shengwang 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2017年第3期333-340,共8页
OBJECTIVE: To examine the neuroprotective effect of extract from Naomaitong following focal cerebral ischemia reperfusion induced by occlusion of middle cerebral artery(MCA), and to determine the biochemical alteratio... OBJECTIVE: To examine the neuroprotective effect of extract from Naomaitong following focal cerebral ischemia reperfusion induced by occlusion of middle cerebral artery(MCA), and to determine the biochemical alterations in urine using proton nuclear magnetic resonance spectroscopy and principal component analysis.METHODS: Wistar rats were randomly assigned tothree groups: sham-operated group, MCA focal cerebral ischemia reperfusion model group, and active extract of Naomaitong treatment group. The model was established by an improved MCA occlusion(MCAO) method. Sham-operated rats received the same surgical procedure, but without occlusion. The Naomaitong treatment group were treated with active extract from Naomaitong at a dose of3.0 g·kg-·1d-1. Brain tissues and urine samples were collected from all groups for histopathological assessment and proton nuclear magnetic resonance spectroscopy-based metabonomics, respectively.RESULTS: Hematoxylin-eosin and triphenyl tetrazolium chloride staining of brain tissues showed a significant decrease in cerebral infarction area in the Naomaitong group. In model rats, metabonomic analyses showed increased urinary levels of glutamate, taurine, trimetlylamine oxide, betaine, and glycine, and reduced levels of creatinine and creatine.Naomaitong regulated the metabolic changes by acting on multiple metabolic pathways, including glycine metabolism, glutaminolysis, transmethylation metabolism and creatinine metabolism.CONCLUSION: These data demonstrate that extract from Naomaitong is neuroprotective against focal cerebral ischemia induced by MCAO, and can alleviate biochemical changes in urinary metabolism. Metabonomics may be a useful approach for assessing the biochemical mechanisms underlying the neuroprotective actions of extract from Naomaitong. 展开更多
关键词 Cerebrovascular circulation REPERFUSION Middle cerebral artery Principal componentanalysis METABONOMICS Magnetic resonance spec-troscopy Naomaitong
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Role of Nanocavity Plasmons in Tunneling Electron Induced Light Emission on and near a Molecule 被引量:1
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作者 Hui-fang Wang Gong Chen +1 位作者 Xiao-guang Li Zhen-chao Dong 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2018年第3期263-268,367,共7页
By using a microscopic quantum model, we study theoretically different roles of nanocavity plasmons in scanning tunneling microscope(STM) induced light emission upon selective initial excitation of molecules or plasmo... By using a microscopic quantum model, we study theoretically different roles of nanocavity plasmons in scanning tunneling microscope(STM) induced light emission upon selective initial excitation of molecules or plasmons. The time evolution and spectroscopic properties of the emission from the coupled plasmon-molecule system in each case are studied using time-dependent quantum mater equations. When the STM tip is placed on the molecule to ensure direct carrier injection induced molecular excitation, the major role of the plasmons is to enhance the molecular emission via increasing its radiative decay rate, resulting in sharp molecule-specific emission peaks. On the other hand, when the STM tip is located in close proximity to the edge of the molecule but without direct carrier injection into the molecule, the role of the plasmon-molecule coupling is to cause destructive interferences between the two quantum objects, leading to the occurrence of Fano dips around the energy of the molecular exciton in the plasmonic emission spectra. 展开更多
关键词 Scanning TUNNELING MICROSCOPE INDUCED luminescence PLASMON enhanced spec-troscopy Fano resonance Quantum master equation
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02(1△) Yield Measurement by Raman Spectroscopy With Elimination of Chlorine Fluorescence Interference
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作者 Rong-rong Cui Wen-bo Shi +3 位作者 Lie-zheng Deng He-ping Yang Guo-he Sha Cun-hao Zhang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第2期142-146,I0003,共6页
Deleterious chlorine fluorescence was found to occur at the same frequency as the Raman scattering of 02 (1 A) and 02 (3 E), seriously affecting the 02 (1 A) yield measurement in the reaction of chlorine with ba... Deleterious chlorine fluorescence was found to occur at the same frequency as the Raman scattering of 02 (1 A) and 02 (3 E), seriously affecting the 02 (1 A) yield measurement in the reaction of chlorine with basic hydrogen peroxide by use of the Raman spectroscopy technique. To solve this problem we have taken advantage of the fact that Raman radiation is always strongly polarized while fluorescence is essentially non-polarized in a gaseous medium. When chlorine utilization of a singlet oxygen generator is 88%, 02(1A) yield reaches (42.4±7.4)% with the effect of chlorine fluorescence completely eliminated. 展开更多
关键词 Chemical oxygen iodine laser Singlet oxygen yield Spontaneous Raman spec-troscopy Chlorine fluorescence
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Two-Dimensional Infrared Spectroscopy of the Photoproduct of π-Cyclopentadienyliron Dicarbonyl Dimer
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作者 Fan Yang Peng-yun Yu +3 位作者 Ji-pei Shi Juan Zhao Xue-mei He Jian-ping Wang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第6期721-728,I0004,共9页
Equilibrium photoproduct of 7r-cyclopentadienyliron dicarbonyl dimer [CpFe(CO)2]2 in non- polar solvent carbon tetrachloride (CC14) is investigated using time-resolved 2D IR spec- troscopy. One of the several poss... Equilibrium photoproduct of 7r-cyclopentadienyliron dicarbonyl dimer [CpFe(CO)2]2 in non- polar solvent carbon tetrachloride (CC14) is investigated using time-resolved 2D IR spec- troscopy. One of the several possible visible-light-driven photoreaction pathways is confirmed and the product is found to contain a di-carbonyl group that exhibits quantum beating be- tween two equivalent transitions in time-resolved 2D IR spectra, which turns out to be the anti-symmetric and symmetric stretching of the terminal carbonyl stretching modes of CpFe(CO)2C1. This is the main product and its reaction pathway involves radical formation, followed by chloride addition. Quantum-chemistry computations support these experimental results. Our results indicate that 2D IR method can be used to identify in situ structures and dynamics of chemical species involved in condensed-phase chemical reactions. 展开更多
关键词 Organometallic compound Photoproduct Carbonyl stretch 2D IR spec-troscopy
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Accurate Measurement of Raman Depolarization Ratio in Gaseous CO2
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作者 靳玉娟 喻远琴 +3 位作者 王钰熙 林珂 周晓国 刘世林 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第1期17-20,I0001,共5页
The Raman depolarization ratios of gaseous CO2 in the spectral range of 1240-1430 cm-I are determined with a sensitive photoacoustic Raman spectroscopy, and more accurate data compared to the literature results are pr... The Raman depolarization ratios of gaseous CO2 in the spectral range of 1240-1430 cm-I are determined with a sensitive photoacoustic Raman spectroscopy, and more accurate data compared to the literature results are presented. The precision of the obtained depolarization ratio is achieved by measuring and fitting the dependence of the PARS signal intensity on the cross angle between the polarizations of two incident laser beams. 展开更多
关键词 Depolarization ratio Accurate measurement Photoacoustic Raman spec-troscopy Global fitting
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Comparative Study on the Infrared Spectra of Straight Guard Hairs of Leopard Cat and Golden Cat
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作者 郭海涛 《Agricultural Science & Technology》 CAS 2013年第11期1683-1686,共4页
[Objective] The paper was to compare the infrared spectra of straight guard hairs of leopard cat and golden cat. [Method] The straight guard hairs of leopard cat and golden cat were detected and analyzed by FTIR (Fou... [Objective] The paper was to compare the infrared spectra of straight guard hairs of leopard cat and golden cat. [Method] The straight guard hairs of leopard cat and golden cat were detected and analyzed by FTIR (Fourier Transform Infrared Spectroscopy). [Result] There was significant interspecific difference in the infrared spectra and second derivative spectra for the middle part of guard hair. An evident M-shaped bimodal absorption peak appeared in golden cat at 648 and 654 cm-1, respectively, while did not appear in leopard cat. The second derivative spec-tra of golden cat at wave numbers from 709 to 763 cm -1 were mainly unimodal peaks with strong peak intensity, while that of leopard cat mainly was M-shaped bi-modal absorption peak with weak peak intensity. It indicated that there was obvious difference in the structure of protein side chain in guard hairs of these two animals. [Conclusion] The FTIR analysis showed great application foreground in the study of animal hairs for interspecific identification. 展开更多
关键词 Leopard Cat Golden cat HAIRS FTIR (Fourier Transform Infrared spec-troscopy
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铱(IV)离子与人血丙种球蛋白的作用研究 被引量:45
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作者 常希俊 黄艳 贺群 《化学学报》 SCIE CAS CSCD 北大核心 2005年第3期223-228,共6页
在 0.1 mol?L-1醋酸-醋酸钠(pH 5.0)体系中, 采用紫外吸收光谱、荧光光谱及同步荧光光谱法研究了人血丙种球蛋白(gamma seroglobulinum humanum, 简称 GSH)与铱(IV)离子的相互作用. 结果表明, Ir(IV)离子使人血丙种球蛋白的构象发生了改... 在 0.1 mol?L-1醋酸-醋酸钠(pH 5.0)体系中, 采用紫外吸收光谱、荧光光谱及同步荧光光谱法研究了人血丙种球蛋白(gamma seroglobulinum humanum, 简称 GSH)与铱(IV)离子的相互作用. 结果表明, Ir(IV)离子使人血丙种球蛋白的构象发生了改变, α-螺旋含量减少, 并且用同步荧光光谱发现 Ir(IV)离子与人血丙种球蛋白的作用位点更接近于色氨酸,从而使色氨酸残基的疏水性略有减小. 荧光光谱结果表明Ir(IV)对人血丙种球蛋白内源荧光(342 nm)产生了较强的荧光猝灭作用, 根据不同温度下 Ir(IV)对人血丙种球蛋白的荧光猝灭作用, 证明了这种荧光猝灭为静态猝灭机制, 计算了其结合常数和结合位点数, 从而得出了静电作用力为其主要的作用力. 展开更多
关键词 人血丙种球蛋白 作用研究 改变 GSH 色氨酸 含量 离子 同步荧光光谱 Α-螺旋 作用位点
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乌骨鸡黑素的一些基本结构特征的初步研究 被引量:39
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作者 袁缨 袁星 白庆余 《动物学报》 SCIE CAS CSCD 1993年第3期287-291,共5页
应用元素分析、电子能谱(XPS)和红外光谱(IR)分析技术对乌骨鸡体内黑素结构特征进行了研究。元素分析结果得到黑素分子中C、H、N、O克原子比率的均值为10:12:1:3.该比值与动物性吲哚黑素的相应元素比例接近。XPS波谱显示出黑素中含有两... 应用元素分析、电子能谱(XPS)和红外光谱(IR)分析技术对乌骨鸡体内黑素结构特征进行了研究。元素分析结果得到黑素分子中C、H、N、O克原子比率的均值为10:12:1:3.该比值与动物性吲哚黑素的相应元素比例接近。XPS波谱显示出黑素中含有两种价态的硫(S~Ⅵ、S~Ⅰ),其中以低价态占优势,S2p电子结合能比人发黑素要大些。氮原子只有一种价态。IR光谱中有五组明显吸收峰,其中以主要表征吲哚环的1619—1632CM^(-1)处的吸引峰最强。以上结果初步表明出乌骨鸡黑素是以吲哚环为主体的异聚物。 展开更多
关键词 乌骨鸡 黑素 元素组成
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稻草原料表面特性FTIR和XPS分析 被引量:25
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作者 吴章康 周定国 《木材工业》 2003年第6期6-8,23,共4页
运用红外光谱(IR)和X射线光电子能谱分析(XPS)方法.考察了热磨处理对稻草表面特性的影响。结果表明:稻草秸秆内表面的活性基团数量和氧碳元素百分比都明显高于外表面;经热磨处理,稻草纤维表面的羟基、甲基、亚甲基等官能团含量显著增加... 运用红外光谱(IR)和X射线光电子能谱分析(XPS)方法.考察了热磨处理对稻草表面特性的影响。结果表明:稻草秸秆内表面的活性基团数量和氧碳元素百分比都明显高于外表面;经热磨处理,稻草纤维表面的羟基、甲基、亚甲基等官能团含量显著增加,氧碳元素百分比相对秸秆表面有大幅度提高,证明热磨处理能增强稻草表面活性,为脲醛树脂稻草中纤板制造的技术可行性提供了依据。 展开更多
关键词 脲醛树脂稻草中纤板 稻草秸秆 表面特性 红外光谱 X射线光电子能谱 热磨处理
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IDEAL-IQ与MRS定量测量肝脏脂肪含量的可行性及相关性 被引量:26
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作者 黄梦月 程敬亮 +3 位作者 吕晓婷 高雪梅 屈召慧 黄梦娜 《放射学实践》 北大核心 2017年第5期447-450,共4页
目的:探讨非对称回波的最小二程估算法迭代水脂分离技术(IDEAL-IQ)与磁共振波谱(MRS)定量测量肝脏脂肪含量的可行性及相关性。方法:采用IDEAL-IQ和MRS定量测量87例非酒精性脂肪肝患者及20例健康志愿者的肝脏脂肪含量,对比分析IDEAL-IQ、... 目的:探讨非对称回波的最小二程估算法迭代水脂分离技术(IDEAL-IQ)与磁共振波谱(MRS)定量测量肝脏脂肪含量的可行性及相关性。方法:采用IDEAL-IQ和MRS定量测量87例非酒精性脂肪肝患者及20例健康志愿者的肝脏脂肪含量,对比分析IDEAL-IQ、MRS测量的脂肪含量的差异及相关性。结果:107例受检者中IDEAL-IQ扫描成功102例(95.8%,102/107),MRS扫描成功76例(71.0%,76/107),两种检查方法的扫描成功率差异有统计学意义(P<0.05)。76例受检者MRS、IDEAL-IQ均扫描成功,此76位受检者由MRS、IDEAL-IQ测得的相对脂质含量(RLC)、脂肪分数(FF)分别为(17.33±10.86)%、(16.28±10.27)%,两者差异无统计学意义(P=0.192)。IDEAL-IQ与MRS测量肝脏脂肪含量相关性的散点图显示两者呈线性关系,Pearson相关性分析显示RLC和FF呈正相关(r=0.784,P=2.613)。结论:MRS、IDEAL-IQ均可定量测量脂肪肝的脂肪含量,两者测量的肝脏脂肪含量呈线性正相关。 展开更多
关键词 非酒精性脂肪肝 肝脏脂肪含量 磁共振成像 磁共振波谱
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野菊花不同提取物的红外光谱分析 被引量:25
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作者 张艳玲 夏远 +2 位作者 朝格图 周群 孙素琴 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2012年第12期3225-3228,共4页
利用红外光谱的宏观指纹特性,对野菊花不同溶剂提取物的红外光谱图和二阶导数红外光谱图进行了整体分析。可知,野菊花石油醚提取物主含长链脂肪酸(酯)、不饱和酮以及小分子萜类等低极性化合物,乙酸乙酯提取物主含萜类和黄酮类化合物,无... 利用红外光谱的宏观指纹特性,对野菊花不同溶剂提取物的红外光谱图和二阶导数红外光谱图进行了整体分析。可知,野菊花石油醚提取物主含长链脂肪酸(酯)、不饱和酮以及小分子萜类等低极性化合物,乙酸乙酯提取物主含萜类和黄酮类化合物,无水乙醇提取物主含黄酮及黄酮苷类化合物,95%乙醇提取物主含黄酮苷类化合物,去离子水提取物主含多糖及鞣质类等大极性成分。此外,与野菊花指标成分蒙花苷的红外光谱分析比较,可知野菊花无水乙醇提取物中所含有的黄酮量是最多的。因此,利用红外光谱法对中药提取物直接进行分析,可初步识别其主体成分,为下一步制定药效成分的提取方案和检测方法提供方向性参考。 展开更多
关键词 野菊花 傅里叶变换红外光谱 提取物 二阶导数红外光谱
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