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真空技术在分析技术领域的作用——TOF-SIMS分析技术在矿物样品表征上的应用
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作者 王富芳 徐子琪 +2 位作者 郭冲 梁汉东 李展平 《真空》 CAS 2024年第5期97-109,共13页
矿物样品的研究是矿物学、岩石学、矿床学等地质学科的基础,矿物的表面形貌、元素组成和分布特征能够揭示成矿物质来源、成矿过程和地质历史等。本文阐述了对于矿物样品表征具有广泛应用潜力的TOF-SIMS原理、技术优势及其所需的真空条件... 矿物样品的研究是矿物学、岩石学、矿床学等地质学科的基础,矿物的表面形貌、元素组成和分布特征能够揭示成矿物质来源、成矿过程和地质历史等。本文阐述了对于矿物样品表征具有广泛应用潜力的TOF-SIMS原理、技术优势及其所需的真空条件,重点总结了国内外学者应用TOF-SIMS在矿物识别、矿物成像、矿物成分定量分析和深度剖析及矿物加工上的研究进展与存在的问题,并对相关领域进行了展望。 展开更多
关键词 矿物表征 飞行时间二次离子质谱 成像分析
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Offline two-dimensional liquid chromatography coupled with ion mobility-quadrupole time-of-flight mass spectrometry enabling fourdimensional separation and characterization of the multicomponents from white ginseng and red ginseng 被引量:9
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作者 Tiantian Zuo Chunxia Zhang +7 位作者 Weiwei Li Hongda Wang Ying Hu Wenzhi Yang Li Jia Xiaoyan Wang Xiumei Gao Dean Guo 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2020年第6期597-609,共13页
Inherent complexity of plant metabolites necessitates the use of multi-dimensional information to accomplish comprehensive profiling and confirmative identification.A dimension-enhanced strategy,by offline two-dimensi... Inherent complexity of plant metabolites necessitates the use of multi-dimensional information to accomplish comprehensive profiling and confirmative identification.A dimension-enhanced strategy,by offline two-dimensional liquid chromatography/ion mobility-quadrupole time-of-flight mass spectrometry(2 D-LC/IM-QTOF-MS)enabling four-dimensional separations(2 D-LC,IM,and MS),is proposed.In combination with in-house database-driven automated peak annotation,this strategy was utilized to characterize ginsenosides simultaneously from white ginseng(WG)and red ginseng(RG).An offline 2 DLC system configuring an Xbridge Amide column and an HSS T3 column showed orthogonality 0.76 in the resolution of ginsenosides.Ginsenoside analysis was performed by data-independent high-definition MSE(HDMSE)in the negative ESI mode on a Vion?IMS-QTOF hybrid high-resolution mass spectrometer,which could better resolve ginsenosides than MSEand directly give the CCS information.An in-house ginsenoside database recording 504 known ginsenosides and 58 reference compounds,was established to assist the identification of ginsenosides.Streamlined workflows,by applying UNIFI?to automatedly annotate the HDMSEdata,were proposed.We could separate and characterize 323 ginsenosides(including 286 from WG and 306 from RG),and 125 thereof may have not been isolated from the Panax genus.The established 2 D-LC/IM-QTOF-HDMSEapproach could also act as a magnifier to probe differentiated components between WG and RG.Compared with conventional approaches,this dimensionenhanced strategy could better resolve coeluting herbal components and more efficiently,more reliably identify the multicomponents,which,we believe,offers more possibilities for the systematic exposure and confirmative identification of plant metabolites. 展开更多
关键词 Dimension-enhanced strategy Multicomponent characterization GINSENOSIDE Offline two-dimensional liquid chromatography ion mobility-quadrupole time-of-flight mass spectrometry In-house database
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Dimension-Enhanced Ultra-High Performance Liquid Chromatography/Ion Mobility-Quadrupole Time-of-Flight Mass Spectrometry Combined with Intelligent Peak Annotation for the Rapid Characterization of the Multiple Components from Seeds of Descurainia sophia 被引量:1
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作者 Simiao Wang Xue Li +7 位作者 Boxue Chen Shitong Li Jiali Wang Jing Wang Mingshuo Yang Xiaoyan Xu Hongda Wang Wenzhi Yang 《Phyton-International Journal of Experimental Botany》 SCIE 2022年第3期541-567,共27页
The complex composition of herbal metabolites necessitates the development of powerful analytical techniques aimed to identify the bioactive components.The seeds of Descurainia sophia(SDS)are utilized in China as a co... The complex composition of herbal metabolites necessitates the development of powerful analytical techniques aimed to identify the bioactive components.The seeds of Descurainia sophia(SDS)are utilized in China as a cough and asthma relieving agent.Herein,a dimension-enhanced integral approach,by combining ultra-high performance liquid chromatography/ion mobility-quadrupole time-of-flight mass spectrometry(UHPLC/IMQTOF-MS)and intelligent peak annotation,was developed to rapidly characterize the multicomponents from SDS.Good chromatographic separation was achieved within 38 min on a UPLC CSH C18(2.1×100 mm,1.7μm)column which was eluted by 0.1%formic acid in water(water phase)and acetonitrile(organic phase).Collision-induced dissociation-MS^(2)data were acquired by the data-independent high-definition MS^(E)(HDMS^(E))in both the negative and positive electrospray ionization modes.A major components knockout strategy was applied to improve the characterization of those minor ingredients by enhancing the injection volume.Moreover,a self-built chemistry library was established,which could be matched by the UNIFI software enabling automatic peak annotation of the obtained HDMS^(E)data.As a result of applying the intelligent peak annotation workflows and further confirmation process,a total of 53 compounds were identified or tentatively characterized from the SDS,including 29 flavonoids,one uridine derivative,four glucosides,one lignin,one phenolic compound,and 17 others.Notably,four-dimensional information related to the structure(e.g.,retention time,collision cross section,MS^(1)and MS^(2)data)was obtained for each component by the developed integral approach,and the results would greatly benefit the quality control of SDS. 展开更多
关键词 Descurainia sophia multicomponent characterization ultra-high performance liquid chromatography ion mobility/quadrupole time-of-flight mass spectrometry high-definition MS^(E) flavonoid
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Influence of Basicity on the Formation of Cluster Ions/Adduct Ions for Organic Ammonium Halides by Positive Secondary Ion Mass Spectrometry
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作者 FU Hua CHEN Xin +4 位作者 LI Zhao long ZHAO Yu fen WANG Jing zun XIAO Hong zhan WU Yi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1997年第4期93-97,共5页
InfluenceofBasicityontheFormationofClusterIons/AdductIonsforOrganicAmmoniumHalidesbyPositiveSecondaryIonMasS... InfluenceofBasicityontheFormationofClusterIons/AdductIonsforOrganicAmmoniumHalidesbyPositiveSecondaryIonMasSpectrometryFUHua,... 展开更多
关键词 Positive secondary ion mass spectrometry(PSIMS) Organic ammonium halide BASICITY Cluster ion /Adduct ion
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石墨烯负载纳米Ag颗粒增强ToF-SIMS分子离子峰
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作者 孙立民 丁雪 +1 位作者 陈振营 张南南 《实验室研究与探索》 CAS 北大核心 2023年第5期53-56,67,共5页
制备石墨烯与纳米Ag颗粒的复合材料(AgNP-GE),并用作新型衬底/基质材料,研究了Ag纳米颗粒对有机物分子峰的增强检测机制。用溶液滴涂法将两种样品Irganox 1010与Risperidone分散到AgNP-GE衬底上,并以ToF-SIMS对其表征。实验发现,两种样... 制备石墨烯与纳米Ag颗粒的复合材料(AgNP-GE),并用作新型衬底/基质材料,研究了Ag纳米颗粒对有机物分子峰的增强检测机制。用溶液滴涂法将两种样品Irganox 1010与Risperidone分散到AgNP-GE衬底上,并以ToF-SIMS对其表征。实验发现,两种样品均检测出(M+Ag)^(+),但Irganox 1010更容易产生(M+Ag)^(+),而Risperidone更容易产生(M+H)^(+)。表明AgNP-GE衬底可以起到类似氧化银(AgO)衬底的作用而形成(M+Ag)^(+)。由于石墨烯衬底自身有助于有机分子的(M+H)^(+)的形成,AgNP-GE有望成为提高有机物分子的分子离子峰检测灵敏度的一种新型基质材料。 展开更多
关键词 飞行时间二次离子质谱 分子离子峰增强 纳米银颗粒 石墨烯
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FIB-TOF-SIMS联用技术在矿物学研究中的应用 被引量:4
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作者 王涛 葛祥坤 +1 位作者 范光 郭冬发 《铀矿地质》 CAS CSCD 2019年第4期247-252,共6页
基于聚焦离子束扫描电子显微镜的飞行时间二次离子质谱联用技术同时具备了聚焦离子束高空间分辨率以及飞行时间二次离子质谱轻元素、同位素分析以及较低的元素检出限的优势。可以实现:扫描电镜下原位分析H、Li、Be、B等轻元素;元素分布... 基于聚焦离子束扫描电子显微镜的飞行时间二次离子质谱联用技术同时具备了聚焦离子束高空间分辨率以及飞行时间二次离子质谱轻元素、同位素分析以及较低的元素检出限的优势。可以实现:扫描电镜下原位分析H、Li、Be、B等轻元素;元素分布的纳米级横向空间分辨率;元素三维空间分布。能够同时得到纳米级矿物的形貌、元素组成以及元素空间分布信息,该技术在地学领域有广阔的应用前景。 展开更多
关键词 飞行时间二次离子质谱 聚焦离子束扫描电镜 元素三维空间分布 轻元素分析 纳米级空间分辨率
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A depressant for marmatite flotation:Synthesis,characterisation and floatation performance 被引量:2
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作者 Tichen Wang Guiju Sun +5 位作者 Jiushuai Deng Hongxiang Xu Guoyong Wang Mingzhen Hu Qizheng Qin Xiaohao Sun 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第6期1048-1056,共9页
This study synthesised a zincic salt(ZS)as a depressant for marmatite-galena separation.The effect of ZS on the flotation of marmatite and galena was investigated through micro-flotation tests.88.89%of the galena was ... This study synthesised a zincic salt(ZS)as a depressant for marmatite-galena separation.The effect of ZS on the flotation of marmatite and galena was investigated through micro-flotation tests.88.89%of the galena was recovered and 83.39%of the marmatite was depressed with ZS dosage of 750 mg·L^(−1)at pH=4.The depression mechanism of ZS on marmatite was investigated by a variety of techniques,including adsorption measurements,Fourier transform infrared(FTIR),X-ray photoelectron spectroscopic(XPS)analysis,and time of flight secondary ion mass spectrometry(ToF-SIMS).Results of adsorption tests and FTIR reveal that ZS adsorbed on marmatite surface and impeded the subsequent adsorption of butyl xanthate(BX).The results of XPS and ToF-SIMS indicate that the ZnO_(2)^(3-)released by ZS could be chemisorbed on the marmatite surface and depress marmatite flotation. 展开更多
关键词 MARMATITE zincic salt flotation separation depression mechanism time of flight secondary ion mass spectrometry
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新疆汉代羊毛织物染料的飞行时间二次离子质谱表征
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作者 刘婕 陈相龙 +2 位作者 梁汉东 铁偲 李展平 《质谱学报》 EI CAS CSCD 北大核心 2024年第3期386-395,I0003,共11页
汉代女性干尸着鲜艳的红-蓝-浅黄三色羊毛纤维编制的华丽服饰,本研究以织物片段作为研究样本,主要采用飞行时间二次离子质谱(TOF-SIMS)法对其染料进行表征。离子成像与高质量分辨数据显示:红色纤维表面产生汞同位素离子(^(202)Hg+和^(19... 汉代女性干尸着鲜艳的红-蓝-浅黄三色羊毛纤维编制的华丽服饰,本研究以织物片段作为研究样本,主要采用飞行时间二次离子质谱(TOF-SIMS)法对其染料进行表征。离子成像与高质量分辨数据显示:红色纤维表面产生汞同位素离子(^(202)Hg+和^(199)Hg+)、汞-硫离子(HgS^(+),m/z 234)、硫同位素离子(^(32)S−和^(34)S−)等,指示其染料属于天然无机矿物朱砂(HgS);蓝色纤维则出现目标化合物的准分子离子m/z 263([M+H]^(+)),以及合理的碎片离子系列,如m/z 235(C_(15)H_(11)N_(2)O^(+))和m/z 247(C_(16)H_(11)N_(2)O^(+))等,指示其呈色来自经典天然植物有机染料靛蓝(C_(16)H_(10)N_(2)O_(2),分子质量262.0742);浅黄纤维未检出有机染料(如姜黄)或无机染料(如铁黄),其呈色可能是白色羊毛自然老化陈旧所致。本工作表明,擅长微区原位与超高灵敏度检测的TOF-SIMS法既适用于有机染料分析,也适用于无机染料分析,该方法有望在考古和博物馆馆藏相关研究中获得广泛应用。 展开更多
关键词 染料 汉代 织物 有机 无机 飞行时间二次离子质谱(tof-sims)
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基于质谱的单细胞分析技术研究新进展
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作者 尤穆英楠 刘心昱 +1 位作者 石先哲 许国旺 《质谱学报》 EI CAS CSCD 北大核心 2024年第3期316-331,I0001,共17页
细胞是生物体最基本的结构和功能单位。近年来,人们对细胞异质性的关注越来越多。为了分析细胞的这种异质性,避免单细胞信息被群体细胞的平均值所淹没,单细胞分析技术不断发展起来。由于单细胞的体积小,内含物质含量低且种类繁多,某些... 细胞是生物体最基本的结构和功能单位。近年来,人们对细胞异质性的关注越来越多。为了分析细胞的这种异质性,避免单细胞信息被群体细胞的平均值所淹没,单细胞分析技术不断发展起来。由于单细胞的体积小,内含物质含量低且种类繁多,某些物质在细胞内的变化迅速,分析过程中不同物质之间相互干扰,造成了单细胞分析极具挑战性。基于质谱的单细胞分析技术具有通用性强、无需标记、高灵敏度、高分辨率、高选择性的优点,已逐渐在单细胞分析技术中脱颖而出,成为单细胞分析的理想工具。本文系统地总结了近5年来基于质谱的单细胞分析技术的最新进展,包括电喷雾电离质谱、激光解吸电离质谱、二次离子质谱、电感耦合等离子体质谱,并对未来的研究和技术方向进行展望,希望为单细胞质谱分析技术的研究提供参考。 展开更多
关键词 单细胞 电喷雾电离质谱(ESI-MS) 激光解吸电离质谱(LDI-MS) 二次离子质谱(SIMS) 电感耦合等离子体质谱(ICP-MS)
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使用飞行时间二次离子质谱法判定痕量氧元素的测试方法
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作者 冯殿福 崔云 +2 位作者 陶春先 杨峰 侯瑶 《理化检验(物理分册)》 CAS 2024年第7期31-34,共4页
采用飞行时间二次离子质谱法对CaF_(2)晶体、YF_(3)薄膜和Au薄膜中的痕量氧元素进行测试。结果表明:通过改变分析离子源光阑大小来改变离子束流,进而改变作用在试样表面的单位面积离子剂量,当离子束流增大时,CaF_(2)晶体与YF_(3)薄膜的... 采用飞行时间二次离子质谱法对CaF_(2)晶体、YF_(3)薄膜和Au薄膜中的痕量氧元素进行测试。结果表明:通过改变分析离子源光阑大小来改变离子束流,进而改变作用在试样表面的单位面积离子剂量,当离子束流增大时,CaF_(2)晶体与YF_(3)薄膜的氟离子、氧离子产额均增加,表明CaF_(2)晶体与YF_(3)薄膜中存在氧元素,测试结果与CaF_(2)的紫外光谱测试结果和YF_(3)薄膜的红外光谱测试结果相吻合;当离子束流增大时,金离子产额增加,而氧离子产额无明显变化,说明检测到的氧元素来自试验环境中的残余气体,Au膜中不存在氧元素。 展开更多
关键词 飞行时间二次离子质谱 痕量元素 残余气体 离子束流
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Al在不同类型Si基中的扩散深度差异及其温度相关性研究
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作者 刘雪婷 孙恒志 +4 位作者 段丙皇 王扶刚 杨帆 卢子伟 王铁山 《现代应用物理》 2024年第5期164-172,181,共10页
金属原子在半导体材料中的扩散对半导体器件的电阻率、传导率和光电学性能有直接影响。采用飞行时间二次离子质谱分析技术,结合分子动力学模拟方法研究了常用金属原子Al在不同Si基中的扩散深度差异及其温度相关性。实验结果表明,Al在本... 金属原子在半导体材料中的扩散对半导体器件的电阻率、传导率和光电学性能有直接影响。采用飞行时间二次离子质谱分析技术,结合分子动力学模拟方法研究了常用金属原子Al在不同Si基中的扩散深度差异及其温度相关性。实验结果表明,Al在本征、N型以及P型Si基中的扩散深度随温度的升高而增加,其中,Al在P型Si基中的扩散深度大于本征和N型Si基。模拟结果表明,Al在Si基中的扩散深度和扩散系数随温度的升高而增加,温度增高至625 K后其扩散行为更为显著,与实验结果相符。研究表明Al在Si中的扩散行为与Si基的性质及环境温度密切相关。相关研究为深入了解Al在Si基中的扩散及其温度相关性提供了重要基础,同时也为探索其他金属在Si基中的扩散行为以及半导体器件加工工艺的优化提供了新的思路和参考依据。 展开更多
关键词 金属扩散 温度相关性 飞行时间二次离子质谱 分子动力学模拟
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锂电池内部结构原位表征方法开发与验证 被引量:1
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作者 韩瑶 朱燕华 +2 位作者 鲍中秋 张莹 何琳 《实验室研究与探索》 CAS 北大核心 2024年第5期24-27,67,共5页
锂电池材料与空气接触会迅速发生反应,导致原始形貌和性能发生改变,限制了其构效关系的进一步深入解析,是锂电池研究领域亟待解决的瓶颈问题。因此,需要设计一种隔绝空气条件下未氧化锂电池内部结构微观尺度上的原位表征方法。目前,传... 锂电池材料与空气接触会迅速发生反应,导致原始形貌和性能发生改变,限制了其构效关系的进一步深入解析,是锂电池研究领域亟待解决的瓶颈问题。因此,需要设计一种隔绝空气条件下未氧化锂电池内部结构微观尺度上的原位表征方法。目前,传统的聚焦离子束(FIB)、扫描电子显微镜(SEM)、X射线能量色散谱(EDS)、电子背散射衍射(EBSD)和飞行时间二次离子质谱(TOF-SIMS)等技术的表征方法相对独立,一次性装样就完成上述全部测试的应用尚未见相关文献。利用70°预倾台,在常规扫描电子显微镜、X射线能量色散谱和电子背散射衍射技术的基础上,采用聚焦离子束与飞行时间二次离子质谱联用技术,建立了一个真空环境下一次性装样就可完成锂电池正极材料内部结构表征的方法,并验证了该方法的可行性。这种方法还可以推广至其他类似结构的材料研究中,具有广泛的应用范围和广阔的应用前景。 展开更多
关键词 锂电池 原位表征方法 聚焦离子束 飞行时间二次离子质谱
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基于原位液相飞行时间二次离子质谱的电化学固液界面研究
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作者 张燕燕 汪福意 《质谱学报》 EI CSCD 北大核心 2024年第1期1-13,I0001,共14页
电化学界面是能源转换与存储、生物化学、传感器和腐蚀等领域的核心,研究电化学界面结构与性能的关系一直是电化学和化学测量学的热点与难点。本文重点介绍了基于高真空兼容微流控装置的原位液相飞行时间二次离子质谱(ToF-SIMS)技术的... 电化学界面是能源转换与存储、生物化学、传感器和腐蚀等领域的核心,研究电化学界面结构与性能的关系一直是电化学和化学测量学的热点与难点。本文重点介绍了基于高真空兼容微流控装置的原位液相飞行时间二次离子质谱(ToF-SIMS)技术的原理、特性,及其在电化学固液界面实时、原位探测方面的研究进展。随着微流控装置的进一步创新以及ToF-SIMS仪器的不断发展,原位液相ToF-SIMS将为电催化、电池等领域的复杂电化学固液界面研究提供重要手段。 展开更多
关键词 电化学固液界面 原位液相飞行时间二次离子质谱 原位分析 实时分析
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适温离子交换掺铒铌酸锂薄膜的制备研究
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作者 何雨轩 吴江威 +1 位作者 陈玉萍 陈险峰 《人工晶体学报》 CAS 北大核心 2024年第3期441-448,共8页
本文通过制备KNO_(3)和Er(NO_(3))_(3)熔融混合物,将其与铌酸锂薄膜在高温管式炉中混合进行适温热扩散,并结合退火工艺,发明了一种直接在铌酸锂薄膜上掺杂Er^(3+)的方法。通过不断变换热扩散温度、掺杂试剂浓度比例和晶体切向等参数,用... 本文通过制备KNO_(3)和Er(NO_(3))_(3)熔融混合物,将其与铌酸锂薄膜在高温管式炉中混合进行适温热扩散,并结合退火工艺,发明了一种直接在铌酸锂薄膜上掺杂Er^(3+)的方法。通过不断变换热扩散温度、掺杂试剂浓度比例和晶体切向等参数,用控制变量法探究了不同参数对适温离子交换法掺杂Er^(3+)效果的影响,在热扩散和退火温度360℃及KNO_(3)和Er(NO_(3))_(3)质量比25∶1的参数设置下获得了表面形貌较佳的Z切掺铒铌酸锂薄膜。通过飞行时间二次离子质谱仪并利用已知掺杂浓度的薄膜进行定标,检测了所获得的掺铒铌酸锂薄膜中的Er^(3+)浓度情况,对所采用适温离子交换法的有效性进行了验证。这一方法大幅简化了铌酸锂薄膜掺杂的工艺,同时节约了成本,有助于后续在铌酸锂薄膜平台上实现分区掺杂的工作,为未来定制化铌酸锂光子集成平台的搭建提供参考。 展开更多
关键词 铌酸锂薄膜 Er^(3+) 适温离子交换 二次离子质谱仪
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Compositional and Structural Study of Macerals in Coals and Source Rocks Using SIMS
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作者 刘大锰 金奎励 毛鹤龄 《International Journal of Mining Science and Technology》 SCIE EI 1997年第1期11-18,共8页
The authors applied the Secondary Ion Mass Spectrometry (SIMS) technique to the analysis of compositions and structures of vitrinites fusinites, fusinites bitumens and graptolites in the hydrocarbon source rocks with ... The authors applied the Secondary Ion Mass Spectrometry (SIMS) technique to the analysis of compositions and structures of vitrinites fusinites, fusinites bitumens and graptolites in the hydrocarbon source rocks with different maturities dscribed their SIMS spectral characteristics and found that different macerals have differnt spectra which, reflected the compositional and structural differences of macerals. Moreover, the change bod of parameter CH2+/CH3+ can be used for the evaluation of thermal evolution regularity of macerals in the hydrocarbon source rocks The study results show that the SIMS technique is a powerful means for microara analysis of macerals in coals and source rocks. It is certain that the study level of macerals can be raised by detailed study of SIMS results of SIMS results of macerals. 展开更多
关键词 MACERALS of COALS and source ROCKS chemical composition and structure secondary ion mass spectrometry
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Probing interaction of melittin with lipid membranes using liquid secondary ion mass spectrometry
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作者 武轶 隋森芳 《Science China Chemistry》 SCIE EI CAS 1998年第1期77-84,共8页
The membrane insertion mechanism of toxic protein is a very active domain in the study of molecular biology. and the “anchor state” of the membrane-hund protein on membrane is the key problem which it is difficult t... The membrane insertion mechanism of toxic protein is a very active domain in the study of molecular biology. and the “anchor state” of the membrane-hund protein on membrane is the key problem which it is difficult to solve with traditional methotls. In the present work we first studied the “anchor state” of melittin on membrane using liquid secondary ion mass spectrometry (LSIMS) in combination with proteolysis by specific enzyme. The results show that the membrane-bound melittin molecules mainly take the conformation in which the axis of α-helix lies parallel to the membrane surface and the side containing Lys7, Lys2I and Arg22 faces the outside of the lipid membrane. This discovery is very significant to the studies of membrane insertion mechanism. The results also indicate that the combination of mass spectrometry technique with the proteolysis by specific enzyme has provided a very new and effective method for the studies of the membrane insertion mechanism. 展开更多
关键词 MELITTIN LIQUID secondary ion mass spectrometry protein orientation LIPID membrane.
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Probing the Proteolysis of Melittin Using Liquid Secondary Ion Mass Spectrometry
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作者 武轶 王敬尊 隋森芳 《Tsinghua Science and Technology》 SCIE EI CAS 1997年第1期57-60,共4页
Liquid secondary ion mass spectrometry(LSIMS) was used to probe the proteolysis of melittin by trypsin and pepsin. The results showed that LSIMS is good for monitoring proteolytic reactions. It can not only identify... Liquid secondary ion mass spectrometry(LSIMS) was used to probe the proteolysis of melittin by trypsin and pepsin. The results showed that LSIMS is good for monitoring proteolytic reactions. It can not only identify the proteolytic products of proteins, but also be used to research the dynamics of proteolytic reactions. The proteolysis of melittin by trypsin gave seven main peptide fragments: 1, AA 1 AA 7 ; 2, AA 1 AA 21 ;3, AA 1 AA 22 ; 4, AA 1 AA 23 ; 5, AA 1 AA 24 ; 6, AA 8 AA 21 ; 7, AA 8 AA 22 . The proteolysis of melittin with pepsin gave thirteen peptide fragments: 1, AA 1 AA 3; 2, AA 4 AA 6;3, AA 1 AA 4;4, AA 1 AA 5 ;5, AA 1 AA 6 ;6, AA 1 AA 8;7, AA 7 AA 13 ;8, AA 10 AA 13 ;9, AA 14 AA 16 ;10, AA 14 AA 26 ;11, AA 15 AA 26 ;12, AA 17 AA 26 ;13, AA 20 AA 26 . 展开更多
关键词 MELITTIN PROTEOLYSIS liquid secondary ion mass spectrometry
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Layer-by-Layer Analysis of the Composition of Thin Films by SIMS and Raman Spectroscopy
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作者 Nikolay N. Nikitenkovt A. N. Nikitenkov Yu. I. Turin I. V. Dushkin V. S. Sypchenko O. V. Vilhivskaya 《Journal of Chemistry and Chemical Engineering》 2014年第2期187-190,共4页
In this study, thin films were produced by magnetron sputtering NC (nanocrystalline) specimens of titanium saturated in hydrogen and were evaluated by layer-by-layer SIMS (secondary ion mass spectrometry) and Rama... In this study, thin films were produced by magnetron sputtering NC (nanocrystalline) specimens of titanium saturated in hydrogen and were evaluated by layer-by-layer SIMS (secondary ion mass spectrometry) and Raman spectroscopy. Due to magnetron sputtering, the chemical composition of the films was non-homogeneous and was variable among layers. Moreover, in the deposition of specimens saturated with hydrogen, hydrogen diffused throughout the depth of the film; diffusion, however, was restricted to the area near the film-substrate interface, affecting less than 50% of the thickness of the film. 展开更多
关键词 Thin films HYDROGEN Raman spectroscopy secondary ion mass spectrometry.
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Source Rock Classification and the Basic Structure of Coal and Kerogen
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作者 金奎励 杨陆武 《Journal of China University of Mining and Technology》 2002年第1期1-5,共5页
In accordance with the confusion on classification of source rocks, the authors raised a source rock classification for its enriched and dispersed organic matter types based on both Alpern’s idea and maceral genesis/... In accordance with the confusion on classification of source rocks, the authors raised a source rock classification for its enriched and dispersed organic matter types based on both Alpern’s idea and maceral genesis/composition. The determined rock type is roughly similar to palynofacies of Combaz , whereas it is "rock maceral facies (for coal viz. coal facies)" in strictly speaking. Therefore, it is necessary to use the organic ingredients classification proposed by the authors so that it can be used for both maceral analysis and environment research . This source rock classification not only shows sedimentology and diagenetic changes but also acquires organic matter type even if hydrocarbon potential derived from maceral’s geochemical parameters. So, it is considered as genetic classification. The "rock maceral facies" may be transformed to sedimentary organic facies , which is used as quantitative evaluation means if research being perfect.Now, there are many models in terms of structure either for coal or for kerogen. In our opinion, whatever coal or kerogen ought be polymer, then we follow Combaz’s thought and study structure of amorphous kerogens which are accordance with genetic mechanism showing biochemical and geochemical process perfectly. Here, we use the time of flight secondary ion mass spectrometry (TOFSIMS) to expand Combaz’s models from three to five. They are also models for coal. 展开更多
关键词 Source rock classification organic ingredient classification basic structure for coal/kerogen time of flight secondary ion mass spectrometry (TOFSIMS)
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Analysis of the linkage positions and isomers of monosaccharide units in oligosaccharides by negative secondary ion mass spectrometry in combination with the stereoselective reaction with substituted boronic acid
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作者 YAN,Lin FANG,Yi-Wei Institute of Chemistry,Chinese Academy of Sciences,Beijing 100080 《Chinese Journal of Chemistry》 SCIE CAS CSCD 1993年第1期53-58,共8页
The negative secondary ion mass spectrometry,in combination with the stereoselective derivatizations with substituted boronic acid RB(OH)_2,was used in the analysis of fourteen oligosac- charides.The mass spectra of t... The negative secondary ion mass spectrometry,in combination with the stereoselective derivatizations with substituted boronic acid RB(OH)_2,was used in the analysis of fourteen oligosac- charides.The mass spectra of the derivatives provide information on their linkage Positions and iso- merism of the individual monoscaccharide units.The results indicated that among the derivatives of the oligosaccharides analyzed,those with 1—4 and 1—6 linkages all presented the ion peaks at m/z 287,sometimes one more peak at m/z 449.Furthermore,a relationship was found between the linkage positions and the intensity orders of the derivative ions.Finally,the derivatives of the disaccharides with a galactose presented an intense ion peak at m/z 347,and those of oligosaccharides with 1—6 linkage to a galactose at terminal presented the ion at m/z 317.In the case of oligosaccharides with a fructose residue,characteristic ion of m/z 155 was produced.The conditions of stereoselective derivatizations and mass spectrometry were studied,in order to obtain a better reproducibility of the mass spectra. 展开更多
关键词 Analysis of the linkage positions and isomers of monosaccharide units in oligosaccharides by negative secondary ion mass spectrometry in combination with the stereoselective reaction with substituted boronic acid acid
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