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Wavelength calibration and spectral analysis of vacuum ultraviolet spectroscopy in EAST
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作者 计华健 张洪明 +6 位作者 吕波 Cheonho BAE 何梁 林子超 尹相辉 沈永才 戴舒宇 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第8期37-43,共7页
A vacuum ultraviolet(VUV)spectroscopy with a focal length of 1 m has been engineered specifically for observing edge impurity emissions in Experimental Advanced Superconducting Tokamak(EAST).In this study,wavelength c... A vacuum ultraviolet(VUV)spectroscopy with a focal length of 1 m has been engineered specifically for observing edge impurity emissions in Experimental Advanced Superconducting Tokamak(EAST).In this study,wavelength calibration for the VUV spectroscopy is achieved utilizing a zinc lamp.The grating angle and charge-coupled device(CCD)position are carefully calibrated for different wavelength positions.The wavelength calibration of the VUV spectroscopy is crucial for improving the accuracy of impurity spectral data,and is required to identify more impurity spectral lines for impurity transport research.Impurity spectra of EAST plasmas have also been obtained in the wavelength range of 50–300 nm with relatively high spectral resolution.It is found that the impurity emissions in the edge region are still dominated by low-Z impurities,such as carbon,oxygen,and nitrogen,albeit with the application of fulltungsten divertors on the EAST tokamak. 展开更多
关键词 vacuum ultraviolet spectroscopy wavelength calibration impurity spectra
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Investigation on Binding between Cations and Amides using UV Raman Spectroscopy
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作者 Yi-xuan Liu Zhou-bing Wang +3 位作者 Jing-jing Wang Kang-zhen Tian Xin Meng Gui-lin Mao 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第4期539-544,I0094,共7页
The interaction of proteins with salt ions plays an important role in life activities.We used butyramide as a model molecule to investigate the interaction of protein backbones with cations.The experiment was performe... The interaction of proteins with salt ions plays an important role in life activities.We used butyramide as a model molecule to investigate the interaction of protein backbones with cations.The experiment was performed in an aqueous solution of metal chloride using UV Raman spectroscopy.It was found that well-hydrated metal cations(Ca^(2+),Mg^(2+))tend to bind to C=O in the amide bond,resulting in redistribution of the amide I band peaks.Specifically,the peak intensity ratio of 1655 cm^(-1)to 1610 cm^(-1)increases significantly with increasing concentrations.However,this phenomenon is not obviously observed in NaCl solution.Furthermore,we studied the effect of salt ions on the water structures.The addition of Ca^(2+)and Mg^(2+)is beneficial to the enhancement of the water signal at the 3400 cm^(-1)position,while the Na^(+)at the same concentration is not obvious.The results have shown that the interaction between cations and amides satisfies the following order:Ca^(2+)>Mg^(2+)>Na^(+),which conforms to the Hofmeister series. 展开更多
关键词 uv Raman spectroscopy Butyramide Hofmeister
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UV接枝聚硅氧烷-TiO_(2)复合棉织物的制备及性能
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作者 黄守磊 武凤艳 +2 位作者 田喜强 马阳 孙红梅 《印染》 CAS 北大核心 2024年第9期42-45,共4页
通过紫外辐射3-(异丁烯酰氧)丙基三甲氧基硅烷对棉织物进行接枝聚合改性,然后与钛酸四丁酯共水解,形成Si—O—Ti化学键,通过化学键合的形式引入TiO_(2)层。由于Si元素位于棉织物和二氧化钛之间,阻断TiO_(2)光催化降解棉织物。化学键合Ti... 通过紫外辐射3-(异丁烯酰氧)丙基三甲氧基硅烷对棉织物进行接枝聚合改性,然后与钛酸四丁酯共水解,形成Si—O—Ti化学键,通过化学键合的形式引入TiO_(2)层。由于Si元素位于棉织物和二氧化钛之间,阻断TiO_(2)光催化降解棉织物。化学键合TiO_(2)与棉织物的结合强度高,提高了耐久性。TiO_(2)对棉织物的整体结构未造成改变,但棉织物的抗紫外线能力显著提升,禁带宽度变小,光催化自清洁能力增强。 展开更多
关键词 功能整理 二氧化钛 紫外接枝 棉织物 聚硅氧烷 抗紫外 自清洁
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UV-LED表面消毒辐射场的数学模拟体系的建立及试验验证
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作者 童张法 姚森 +4 位作者 江怡清 张连峰 申聪敏 刘乃鑫 闫建昌 《安全与环境学报》 CAS CSCD 北大核心 2024年第10期4042-4051,共10页
为了实现紫外发光二极管(Ultraviolet Light-Emitting Diodes,UV-LED)表面消毒器设计的优化、高效、智能化目的,研究建立了UV-LED表面消毒辐射场的数学模型,并进行了试验验证。根据该数学模型,编写了VBA(Visual Basic for Applications... 为了实现紫外发光二极管(Ultraviolet Light-Emitting Diodes,UV-LED)表面消毒器设计的优化、高效、智能化目的,研究建立了UV-LED表面消毒辐射场的数学模型,并进行了试验验证。根据该数学模型,编写了VBA(Visual Basic for Applications)程序,对辐射场进行了模拟和分析。结果显示,辐射模型的计算值与实测值接近,试验验证了辐射模型的可行性。试验进行了应用举例,当照射距离与灯间距的比值为0.4时,选择最大发光角90°的UV-LED可使辐射场最优化;当照射距离与灯间距的比值为0.8和1.6时,对应的最优选择分别是45°和30°的UV-LED。数学模型和相关计算方法为优化设计紫外线表面消毒设施提供了模拟、优化的有效工具。 展开更多
关键词 环境工程学 紫外发光二极管(uv-LED) 表面消毒 辐射场 数学模拟 试验验证
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红光补充UV-A对叶用莴苣倍半萜内酯类化合物的调控效应 被引量:1
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作者 田原源 查凌雁 +3 位作者 王座祺 段逸文 魏仕伟 章竞瑾 《中国蔬菜》 北大核心 2024年第3期51-58,共8页
叶用莴苣特有的苦味来源于倍半萜内酯类化合物,主要包括山莴苣苦素和莴苣苦素等。为探究紫外光对叶用莴苣生长和倍半萜内酯类化合物的调控作用,以纯红光(180μmol·m^(-2)·s^(-1))为对照,比较了补充UV-A(30μmol·m^(-2)&#... 叶用莴苣特有的苦味来源于倍半萜内酯类化合物,主要包括山莴苣苦素和莴苣苦素等。为探究紫外光对叶用莴苣生长和倍半萜内酯类化合物的调控作用,以纯红光(180μmol·m^(-2)·s^(-1))为对照,比较了补充UV-A(30μmol·m^(-2)·s^(-1))、UV-B(10μmol·m^(-2)·s^(-1))对7个叶用莴苣品种生长及倍半萜内酯类化合物的影响;并进一步分析了红外光添加UV-A补光强度(15、30、45μmol·m^(-2)·s^(-1))及补光时长(0、1、2、3、6、9 d)对叶用莴苣倍半萜内酯类化合物含量的影响。结果表明:添加UV-A处理可显著提高绿罗的地上部鲜质量,显著降低7个叶用莴苣品种的山莴苣苦素和莴苣苦素含量,分别降低了33%~74%和29%~60%。随着UV-A补光强度的增加,叶用莴苣中倍半萜内酯类化合物含量逐渐降低,且以添加30μmol·m^(-2)·s^(-1)UV-A处理2 d后叶用莴苣中山莴苣苦素含量迅速上升,处理3 d时达到峰值,随后逐渐降低;而莴苣苦素含量在处理2 d后基本保持逐步上升的趋势,处理6~9 d时略有下降。综上所述,红光补充适量的UV-A(30μmol·m^(-2)·s^(-1)、3~6 d),可在不影响生物量的基础上显著降低叶用莴苣中倍半萜内酯类化合物含量,从而减轻苦味。 展开更多
关键词 叶用莴苣 紫外光 uv-A 山莴苣苦素 莴苣苦素
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紫外发光二极管(UV-LED)技术对食品微生物灭活应用的研究进展
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作者 李金东 张忠杰 +3 位作者 祁智慧 尹君 金毅 唐芳 《粮油食品科技》 CAS CSCD 北大核心 2024年第2期151-158,共8页
紫外辐照是一种非热杀菌技术,汞蒸气紫外灯是现阶段用于食品卫生处理的主要设备,但受某些因素影响,汞灯的生产使用将逐渐变少,被环保节能的紫外发光二极管(UV-LED)取代是一种不可避免的趋势。本文根据UV-LED发光原理和多波长耦合应用的... 紫外辐照是一种非热杀菌技术,汞蒸气紫外灯是现阶段用于食品卫生处理的主要设备,但受某些因素影响,汞灯的生产使用将逐渐变少,被环保节能的紫外发光二极管(UV-LED)取代是一种不可避免的趋势。本文根据UV-LED发光原理和多波长耦合应用的特点,综述了对微生物灭活的机理、探究了影响灭活效果的因素(波长、紫外剂量和物料特性)、处理食品的灭菌效果以及对部分食品品质的影响,为UV-LED在食品领域的杀菌处理工艺和设备参数优化提供参考。 展开更多
关键词 紫外发光二极管(uv-LED) 微生物灭活 食品行业 非热杀菌技术
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基于EEMs和UV-Vis法相结合的北方某城市原水三氯甲烷生成预测
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作者 黄慧婷 陆瑞 +2 位作者 邹放 汪洋 李春暖 《净水技术》 CAS 2024年第8期135-139,174,共6页
以北方城市某水厂采集的原水作为研究对象,利用三维荧光光谱进行测定,通过计算荧光指数(FI)判断原水中溶解性有机物(DOM)的来源,并考察加氯后的三氯甲烷生成情况与水中DOM紫外-可见分光光谱特性之间的联系。结果表明,当水厂的原水中DOM... 以北方城市某水厂采集的原水作为研究对象,利用三维荧光光谱进行测定,通过计算荧光指数(FI)判断原水中溶解性有机物(DOM)的来源,并考察加氯后的三氯甲烷生成情况与水中DOM紫外-可见分光光谱特性之间的联系。结果表明,当水厂的原水中DOM主要为微生物的代谢产物时,加氯后三氯甲烷的生成量可通过测定溶解性有机物在280 nm处吸光度,进行负对数计算得到-lnA280来反映三氯甲烷生成量,由此提供了一种更加操作简单、成本较低的预测三氯甲烷质量浓度的方法。 展开更多
关键词 饮用水 溶解性有机物(DOM) 氯消毒 三氯甲烷 紫外吸收光谱
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柔性透明导电膜用UV胶的配方探讨
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作者 徐丹丹 秦苏琼 +2 位作者 陶军 瞿然 刘世国 《电子工业专用设备》 2024年第1期43-47,57,共6页
应用于柔性透明导电膜用UV胶压印技术,对柔性透明导电膜产品性能有重要作用,特别是胶的黏度、硬度、附着力、光学性能、耐水性、伸长率等对实现高精度印刷效果、导电膜柔韧性、透光率和稳定性都有重要的意义。根据柔性透明导电膜用UV胶... 应用于柔性透明导电膜用UV胶压印技术,对柔性透明导电膜产品性能有重要作用,特别是胶的黏度、硬度、附着力、光学性能、耐水性、伸长率等对实现高精度印刷效果、导电膜柔韧性、透光率和稳定性都有重要的意义。根据柔性透明导电膜用UV胶实用性能的要求,讨论了柔性透明导电膜用UV胶的配方成份。 展开更多
关键词 柔性透明导电膜 紫外光固化胶(uv胶) 压印
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UV-TiO_(2)-PS光催化降解煤化工废水中含氮有机物 被引量:3
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作者 陈莉荣 宛艳玉 +1 位作者 王瑞 谷振超 《化工环保》 CAS CSCD 北大核心 2023年第3期313-318,共6页
比较了由紫外光(UV)、TiO_(2)、H_(2)O_(2)、过硫酸盐(PS)组合而成的5种工艺对溶液中喹啉的光催化降解效果,分析了影响UV-TiO_(2)-PS降解喹啉的主要因素和降解机理,考察了该体系对吲哚和吡啶的降解效果。实验结果表明:相同条件下,5种体... 比较了由紫外光(UV)、TiO_(2)、H_(2)O_(2)、过硫酸盐(PS)组合而成的5种工艺对溶液中喹啉的光催化降解效果,分析了影响UV-TiO_(2)-PS降解喹啉的主要因素和降解机理,考察了该体系对吲哚和吡啶的降解效果。实验结果表明:相同条件下,5种体系对喹啉的去除效果依次为UV-TiO_(2)-PS>UV-TiO_(2)-H_(2)O_(2)>UV-PS>UV-H_(2)O_(2)>UV-TiO_(2),氧化剂H_(2)O_(2)或PS与UV-TiO_(2)联用,能提高喹啉去除率;在喹啉溶液初始质量浓度20 mg/L、TiO_(2)加入量1.2 g/L、PS加入量0.012 mol/L、初始pH 6.5的最佳工艺条件下,光反应150 min,喹啉去除率为97.07%,光反应180 min,TOC去除率为72.32%;在UV-TiO_(2)-PS降解喹啉的最佳工艺条件下,光反应150 min,该体系对吡啶和吲哚的去除率分别为41.12%和80.13%;UV-TiO_(2)-PS氧化降解喹啉过程中,活性物种的贡献依次为SO_(4)^(-)·>O_(2)-·>·OH>h^(+)。 展开更多
关键词 煤化工废水 喹啉 含氮杂环化合物 紫外光(uv) TiO_(2) 过硫酸盐(PS) 高级氧化
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Strain H_2-419-4 of Haematococcus pluvialis induced by ethyl methanesulphonate and ultraviolet radiation 被引量:9
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作者 孙延红 刘建国 +1 位作者 张晓丽 林伟 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第2期152-156,共5页
Two strains H2-410 and H2-419 were obtained from the chemically mutated survivors of wild Haematococcus pluvialis 2 by using ethyl methanesulphonate (EMS). Strains H2-410 and H2-419 showed a fast cell growth with 13% ... Two strains H2-410 and H2-419 were obtained from the chemically mutated survivors of wild Haematococcus pluvialis 2 by using ethyl methanesulphonate (EMS). Strains H2-410 and H2-419 showed a fast cell growth with 13% and 20% increase in biomass compared to wild type, respectively. Then H2-419-4, a fast cell growth and high astaxanthin accumulation strain, was obtained by exposing the strain H2-419 to ultraviolet radiation (UV) further. The total biomass, the astaxanthin content per cell, astaxanthin production of H2-419-4 showed 68%, 28%, and 120% increase compared to wild H. pluvialis 2, respectively. HPLC (High Performance Liquid Chromatography) data showed also an obvious proportional variation of different carotenoid compositions in the extracts of H2-419-4 and the wild type, although no peak of carotenoids appeared or disappeared. Therefore, the main compositions in strain H2-419-4, like its wild one, were free of astaxanthin, monoester, and diester of astaxanthin. The asexual reproduction in survivors after exposed to UV was not synchronous, and different from the normal synchronous asexual reproduction as the mother cells were motile instead of non-motile. Interestingly, some survivors from UV irradiation produced many mini-spores (or gamete?), the spores moved away from the mother cell gradually 4 or 5 days later. This is quite similar to sexual reproduction described by Elliot in 1934. However, whether this was sexual reproduction remains questionable, as no mating process has been observed. 展开更多
关键词 Haematococcus pluvialis ASTAXANTHIN ethyl methanesulphonate (EMS) ultraviolet radiation (uv
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Development of vacuum ultraviolet spectroscopy for measuring edge impurity emission in the EAST tokamak 被引量:4
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作者 Hongming ZHANG Bo LYU +9 位作者 Liang HE Yongcai SHEN Jun CHEN Jia FU Bin BIN Xunyu WANG Fudi WANG Yingying LI Ling ZHANG Bing LIU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第8期8-13,共6页
The dominant wavelength range of edge impurity emissions moves from the visible range to the vacuum ultraviolet(VUV)range,as heating power increasing in the Experimental Advanced Superconducting Tokamak(EAST).The meas... The dominant wavelength range of edge impurity emissions moves from the visible range to the vacuum ultraviolet(VUV)range,as heating power increasing in the Experimental Advanced Superconducting Tokamak(EAST).The measurement provided by the existing visible spectroscopies in EAST is not sufficient for impurity transport studies for high-parameters plasmas.Therefore,in this study,a VUV spectroscopy is newly developed to measure edge impurity emissions in EAST.One Seya-Namioka VUV spectrometer(McPherson 234/302)is used in the system,equipped with a concave-corrected holographic grating with groove density of 600 grooves mm-1.Impurity line emissions can be observed in the wavelength range ofλ=50-700 nm,covering VUV,near ultraviolet and visible ranges.The observed vertical range is Z=-350-350 mm.The minimum sampling time can be set to 5 ms under full vertical binning(FVB)mode.VUV spectroscopy has been used to measure the edge impurity emission for the 2019 EAST experimental campaign.Impurity spectra are identified for several impurity species,i.e.,lithium(Li),carbon(C),oxygen(O),and iron(Fe).Several candidates for tungsten(W)lines are also measured but their clear identification is very difficult due to a strong overlap with Fe lines.Time evolutions of impurity carbon emissions of CⅡat 134.5 nm and CⅢat 97.7 nm are analyzed to prove the system capability of time-resolved measurement.The measurements of the VUV spectroscopy are very helpful for edge impurity transport study in the high-parameters plasma in EAST. 展开更多
关键词 EAST TOKAMAK IMPURITY tungsten vacuum ultraviolet spectroscopy EDGE IMPURITY EMISSION plasma diagnostics
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Interaction between Eu-phenylalanine and DNA Using Cyclic Voltammetry and UV Spectroscopy 被引量:2
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作者 沈鹤柏 蒯丽衡 +2 位作者 倪丽华 李建粤 章宗穰 《Journal of Rare Earths》 SCIE EI CAS CSCD 1997年第4期60-63,共4页
The interaction between DNA and the Eu(Phe) 3+ 3 complex ion has been studied by means of cyclic voltammetry and differential UV spectroscopy The results depicted an obvious decrease of peak current in CV plot... The interaction between DNA and the Eu(Phe) 3+ 3 complex ion has been studied by means of cyclic voltammetry and differential UV spectroscopy The results depicted an obvious decrease of peak current in CV plot after the reaction between the two species studied The observed peak potential separation was increased but the diffusion coefficient of Eu complex ion was decreased Hypochromicity was observed at 226 and 258 nm after the predicted interaction of them A preliminary interpretation is proposed for discussion 展开更多
关键词 Rare earths DNA Cyclic voltammetry uv spectroscopy
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In Deep UV Quantitative Analysis of Multi-Element Low Alloy Steel by Laser-Induced Breakdown Spectroscopy 被引量:4
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作者 Yong Xin Lanxiang Sun +3 位作者 Zhibo Cong Lifeng Qi Yang Li Zhijia Yang 《Journal of Computer and Communications》 2013年第7期19-22,共4页
The multi-element components of low alloy steel were quantified by using laser-induced breakdown spectroscopy (LIBS) in deep UV. The Nd:YAG pulsed laser was used to produce plasma. The spectrum was simultaneously obta... The multi-element components of low alloy steel were quantified by using laser-induced breakdown spectroscopy (LIBS) in deep UV. The Nd:YAG pulsed laser was used to produce plasma. The spectrum was simultaneously obtained by deep UV spectrometer. This paper studied the influence of experiment parameters on LIBS spectral intensity, such as delay, energy of laser, and the distance between the focusing lens and the surface of the sample. With the optimal expe- riment parameters, the characteristic lines of C, Ni, Si, Cr and Cu contained in low alloy steel were selected for quantit- ative analysis and the calibration curves of these elements were obtained. The linear correlation coefficient was good. Using the calibration curves to quantitative analysis for the sample 05-d, and the relative error of analytical results is less than 10% for most elements. 展开更多
关键词 LASER-INDUCED BREAKDOWN spectroscopy Plasma QUANTITATIVE Analysis DEEP uv
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Interzeolite transformation from FAU to CHA and MFI zeolites monitored by UV Raman spectroscopy 被引量:3
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作者 Juan Zhang Yueying Chu +4 位作者 Xiaolong Liu Hao Xu Xiangju Meng Zhaochi Feng Feng-Shou Xiao 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第12期1854-1859,共6页
As a powerful and sensitive tool for the characterization of zeolite building units,UV Raman spectroscopy has been used to monitor interzeolite transformation from FAU to CHA and MFI zeolites.The results show that the... As a powerful and sensitive tool for the characterization of zeolite building units,UV Raman spectroscopy has been used to monitor interzeolite transformation from FAU to CHA and MFI zeolites.The results show that the behavior of double 6-membered rings(D6Rs)in the FAU zeolite framework plays an important role during the formation of the target product in the interzeolite transformation.For the transformation of FAU to CHA,because both zeolites contain the same D6R units,direct transformation occurs,in which the D6Rs were largely unchanged.In contrast,for the transformation of FAU to MFI,the D6Rs can be divided into two single 6-membered rings(S6Rs),which further assembled into the MFI structure.In this crystallization,5-membered rings(5Rs)are only observed in the MFI framework formation,suggesting that the basic building units in the transformation of FAU to MFI are S6Rs rather than 5Rs.These insights will be helpful for further understanding of the interzeolite transformation. 展开更多
关键词 Interzeolite transformation uv Raman spectroscopy DFT calculation Double 6-memberred rings Decomposition and re-assembly
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Infrared Spectroscopy of Neutral Clusters Based on a Vacuum Ultraviolet Free Electron Laseri 被引量:1
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作者 Gang Li Chong Wang +4 位作者 Hui-jun Zheng Tian-tong Wang Hua Xie Xue-ming Yang Ling Jiang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2021年第1期51-60,I0011,共11页
Spectroscopic characterization of clusters is crucial to understanding the structures and reaction mechanisms at the microscopic level,but it has been proven to be a grand challenge for neutral clusters because the ab... Spectroscopic characterization of clusters is crucial to understanding the structures and reaction mechanisms at the microscopic level,but it has been proven to be a grand challenge for neutral clusters because the absence of a charge makes it di伍cult for the size selection and detection.Infrared(IR)spectroscopy based on threshold photoionization using a tunable vacuum ultraviolet free electron laser(VUV-FEL)has recently been developed in the lab.The IR-VUV depletion and IR+VUV enhancement spectroscopic techniques open new avenues for size-selected IR spectroscopies of a large variety of neutral clusters without confinement(i.e.,an ultraviolet chromophore,a messenger tag,or a host matrix).The spectroscopic principles have been demonstrated by investigations of some neutral water clusters and some metal carbonyls.Here,the spectroscopic principles and their applications for neutral clusters are reviewed. 展开更多
关键词 CLUSTERS Infrared spectroscopy Vacuum ultraviolet free electron laser STRUCTURES Reaction mechanisms
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High-performance frequency stabilization of ultraviolet diode lasers by using dichroic atomic vapor spectroscopy and transfer cavity 被引量:1
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作者 Danna Shen Liangyu Ding +4 位作者 Qiuxin Zhang Chenhao Zhu Yuxin Wang Wei Zhang Xiang Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第7期356-362,共7页
We develop a high-performance ultraviolet(UV)frequency stabilization technique implemented directly on UV diode lasers by combining the dichroic atomic vapor laser lock and the resonant transfer cavity lock.As an exam... We develop a high-performance ultraviolet(UV)frequency stabilization technique implemented directly on UV diode lasers by combining the dichroic atomic vapor laser lock and the resonant transfer cavity lock.As an example,we demonstrate a stable locking with measured frequency standard deviations of approximately 200 kHz and 300 kHz for 399 nm and 370 nm diode lasers in 20 min.We achieve a long-term frequency drift of no more than 1 MHz for the target 370 nm laser within an hour,which is further verified with fluorescence count rates of a single trapped ^171Yb+ion.We also find strong linear correlations between lock points and environmental factors such as temperature and atmospheric pressure.Our approach provides a simple and stable solution at a relatively low cost,and features flexible control,high feedback bandwidth and minimal power consumption of the target UV laser. 展开更多
关键词 frequency stabilization ultraviolet diode laser dichroic atomic vapor spectroscopy transfer cavity
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Characterization on the Exfoliation Degree of Graphite Oxide into Graphene Oxide by UV-visible Spectroscopy 被引量:3
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作者 艾凡荣 ZHONG Yu +1 位作者 HU Xiaowu YAN Xiluan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第3期515-518,共4页
The exfoliation degree of graphite oxide into graphene oxide plays an important role in the massive production method of reduced graphene oxide. It is significant to find a simple and feasible method to analyze the ex... The exfoliation degree of graphite oxide into graphene oxide plays an important role in the massive production method of reduced graphene oxide. It is significant to find a simple and feasible method to analyze the exfoliation degree of graphite oxide. In the present work, graphite oxide was synthesized by a modified Hummers method, and then graphene oxide colloids were obtained by exfoliation of graphite oxide dispersed in de-ionized water. UV-visible spectroscopy was used to characterize the absorption of the graphene oxide colloids, and the concentration of graphene oxide colloids indicated by absorption area of UV-visible spectra was studied. Results show that there is a relatively stable relationship between them, indicating that UV- visible spectroscopy is a potential method for analyzing the exfoliation degree of graphite oxide into graphene oxide. 展开更多
关键词 GRAPHENE graphene oxide graphene oxide colloids uv-visible spectroscopy
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Application of Two-Dimensional Correlation UV-Vis Spectroscopy in Chinese Liquor Moutai Discrimination 被引量:9
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作者 Zhengyong Zhang Jiuying Jiang +3 位作者 Guoxiang Wang Hu Wang Jun Liu Haiyan Wang 《American Journal of Analytical Chemistry》 2015年第5期395-401,共7页
Chinese liquor Moutai is the “National alcoholic drink” in China and plays a very important role of social activities in Chinese people’s life. In pursuit of high profits, some illegal counterfeit Moutai liquors ha... Chinese liquor Moutai is the “National alcoholic drink” in China and plays a very important role of social activities in Chinese people’s life. In pursuit of high profits, some illegal counterfeit Moutai liquors have begun to appear in the market. Therefore, it is an urgent need for new techniques to discriminate the genuine and counterfeit Moutai liquor. In this work, the conventional Ultraviolet-Visible (UV-Vis) spectroscopy and two-dimensional correlation UV-Vis spectroscopy are applied to obtain the UV-Vis characteristic of Moutai liquor and counterfeit one, respectively. The experimental results reveal that the conventional UV-Vis spectra of the genuine and counterfeit Moutai liquor are similar. However, the two-dimensional correlation UV-Vis spectra of them are different and this method would be applied to differentiate the counterfeit Moutai liquor from the genuine Moutai liquor. Compared with conventional methods, this novel method has the advantages of easy operation, simple instrumentation and direct recognition, which make it a potential tool in the fields of food safety. 展开更多
关键词 TWO-DIMENSIONAL CORRELATION SPECTRA uv-VIS spectroscopy Moutai LIQUOR DISCRIMINATION
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Sensitivity Enhancement in Uranium Determination by UV-Visible Spectroscopy Using Ion Imprinted Polymer 被引量:2
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作者 Tulin BICIM Mehmet YAMAN 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2016年第6期1992-1997,共6页
There is need to determination of uranium concentration at ppb level in environmental matrices.Due to low sensitivity of FAAS,UV-Visible Spectroscopy is generally used as measurement technique.In this study,ion-imprin... There is need to determination of uranium concentration at ppb level in environmental matrices.Due to low sensitivity of FAAS,UV-Visible Spectroscopy is generally used as measurement technique.In this study,ion-imprinted polymers(IIP)were prepared for uranyl ion(imprint ion)by formation of ternary(salicylaldoxime and 4-vinylpyridine)complex in 2-methoxy ethanol(porogen)following copolymerization with methacrylic acid(MAA)as a functional monomer and ethylene glycol dimethacrylate(EGDMA)as crosslinking monomer using 2,2-azobisisobutyronitrile as initiator.The synthesized polymers were characterized by FTIR and TGA analysis.ArsenazoⅢin 3M HClO_4 was used as complexing agent in the measurement step.The optimal pH for preconcentration was found to be between 3.5~6.5values.The developed method was applied to uranium(Ⅵ)determination in natural water samples. 展开更多
关键词 URANIUM Ion imprinted polymer ArsenazoⅢ uv-vis spectroscopy
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基于UV-Vis漫反射、Raman与PL光谱联用技术在黄色珍珠无损检测中的应用 被引量:1
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作者 严雪俊 周扬 +3 位作者 胡丹静 俞丹燕 余思逸 严俊 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2023年第6期1703-1710,共8页
应用紫外-可见(UV-Vis)漫反射、拉曼(Raman)与光致发光(PL)光谱就当前市售的大小各异、金色饱和度深浅不一的珍珠其致色属性予以对比分析。结果表明:基于珍珠UV-Vis漫反射光谱特征的差异将金黄色珍珠初分为两种类型:Ⅰ型珍珠其谱图在(36... 应用紫外-可见(UV-Vis)漫反射、拉曼(Raman)与光致发光(PL)光谱就当前市售的大小各异、金色饱和度深浅不一的珍珠其致色属性予以对比分析。结果表明:基于珍珠UV-Vis漫反射光谱特征的差异将金黄色珍珠初分为两种类型:Ⅰ型珍珠其谱图在(360±5) nm处存在吸收带、在(420±10) nm处存在较弱的吸收峰或肩,该类珍珠为当前珍珠销售市场较为常见的自身致色珍珠;除Ⅰ型珍珠外,将其他金黄色系珍珠归属为Ⅱ型,其对应的UV-Vis反射光谱主吸收峰可位于340~430 nm区间,部分Ⅱ型样品在280~600 nm无明显吸收或仅存在较弱的吸收肩。进一步就Ⅱ型珍珠予以Raman光谱检测,在激发强度较低时经处理的Ⅱ型黄色珍珠在150~1 000 cm^(-1)区间可产生较强的荧光峰,且荧光峰的强度明显高于文石约1 086 cm^(-1)处的特征峰。同时,上述经处理的Ⅱ型珍珠对应的PL光谱同样表明在500~600 nm区间的荧光强度显著增大。此外,部分经处理的珍珠其Raman或PL光谱中可见与珍珠组成成分无关的特征峰位。上述珍珠的Raman与PL光谱中出现的异常荧光与外来特征峰可作为珍珠经处理的佐证依据。课题工作为当前金黄色珍珠颜色的形成属性及仿珍珠的鉴定提供理论与技术支撑,同时对于Raman光谱在其他类宝玉石、特别是有机宝石的检测鉴定中具有重要的借鉴意义。 展开更多
关键词 黄色珍珠 天然色 处理色 紫外-可见漫反射光谱 拉曼光谱 光致发光光谱
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