A Study on the Liquid Mass Spectrometer Experimental Technology

以植物中提取的一热不稳定有机化合物为例,分别采用液相质谱仪电喷雾电离源(ESI)和大气压化学电离源(APCI)方法检测。同时对ESI加热毛细管的技术参数设若干温度点(从200~104°C)跟踪检测分析,得出如下结果:对于极性且热不稳定有机化合物适宜的检测方式为ESI,随着加热毛细管温度不断降低,可以获得更为丰富的谱峰信息;在低于通常的加热毛细管温度设置区域能测得其准分子离子峰和相应的碎片峰。表明在液相质谱检测中优化传统溶剂等离子化效应下还必须关注到离子源和加热毛细管温度的选择,这对有机化合物的结构分析极有意义。To improve the detection accuracy and efficiency of the liquid mass spectrometer and the qualitative analysis level of the liquid mass spectrometer for the thermally unstable organic compounds,an optimized experiment technology of the liquid mass spectrometer was introduced for the thermally unstable organic compounds in this paper.A kind of the thermally unstable organic compounds extracted from the plant was detected respectively by electrospray ionization( ESI) and atmospheric pressure chemical ionization( APCI); by setting several temperature points( from 200 °C to 104 °C) of the heated capillary,the detected compounds was tracked and analyzed.With the temperature of the heated capillary reduced,more mass spectrometry information can be obtained.A conclusion could be drawn that the detection method of ESI is suitable to the extremely and thermally unstable organic compounds,the quasi-molecular ions spectrum and the corresponding fragment spectrum could be obtained in the settings area of lower capillary temperature.It was indicated that the ion source and the temperature of the heated capillary must be selected in the detection of the liquid mass spectrometer.It is important for the structure analysis of the thermally unstable organic compounds.厦门大学科技创新基金(XDKJCX20051003

桔皮挥发油、几种人工合成香精中α-柠檬烯含量的比较

目的 　观察桔皮挥发油、几种人工合成香精中α-柠檬烯不同含量结果。方法 　采用气相色谱 -质谱检测挥发油中α-柠檬烯。结果 　芦柑皮挥发油和 3种人工合成香精经色谱分离出 14～ 5 0多个峰不等 ,主要成分均为α-柠檬烯 ,其它各成分的含量均在 15 %以下。其中以香橙油香精含α-柠檬烯量最多 ( 89.49%) ,其次为桔子油香精 ( 88.3 %)。 结论 　挥发油中 80 %是α-柠檬烯 ,若能用人工合成的香精代替天然桔皮挥发油中的α-柠檬烯 ,可解决资源问题。若有人工合成品 ,对研究α-柠檬烯的药理作用取材更为方

The Combustion Property of Rare earth based Fluorite Type Oxide

CE基萤石型材料因低价阳离子ln3＋的掺杂，降低了它的还原温度，增强了氧化还原能力，故可较好地促进甲烷等挥发性有机物的完全燃烧，具有与钙钛矿形型化合物相类似的性能，而其热稳定性更好，因而有望在醇类代用燃料汽车的尾气净化处理中发挥更大作用。Doping with lower valence cations,the reducing temperature of Ce based Fluorite type materials can be lowered,and the reduction oxidation property can be enhanced.This Facilitates the combustion of methane as perovskite compounds do,and the Former has a better thermal stability.This material can play an important role in the treatment of exhaust gas From alcohol Fueled vehicles.福建省自然科学基

肌红蛋白的电喷雾质谱研究——推荐一个化学生物学教学实验

在原有实验的基础上,设计、实践了一个利用电喷雾质谱研究生物大分子与小分子相互作用的更为合理、简单、易行的实验方法。讨论了该实验在化学生物学专业本科生教学工作中的实践效果及经验

高硫合成气制甲硫醇钼基催化剂ESR和XPS表征

研究以 (NH4 ) 6Mo7O2 4 ·4H2 O为前驱物料所制得的MoO3 /K2 CO3 /SiO2 催化剂对高硫化氢合成气一步法合成甲硫醇的催化活性 ,考察K2 CO3 助剂对钼基催化剂催化行为的影响。ESR表征结果显示 ,工作态催化剂观测到氧包围的“oxo -Mo(V)”(g =1.93)、硫包围的“thio -Mo(V)”(g =1.98)和S(g =2 .0 1,g =2 .0 4)等信号 ,随着K2 CO3 添加量的增加 ,oxo -Mo(V)含量增加 ,thio -Mo(V)含量减少 ;XPS表征显示 ,钼包含了Mo4 + 、Mo5+ 和Mo6+ 的混合价态 ,硫包含了S2 -(16 1.5eV)、(S -S) 2 -(16 2 .5eV)和S6+ (16 8.5eV)等 3种物种 ,Mo5+ /Mo4 + 摩比为 0 .4和S2 -/ (S -S) 2 -比接近 1有利于甲硫醇的生

甲烷脱氢芳构化W/HZSM-5基催化剂EPR研究

利用ＥＰＲ等谱学方法，对Ｗ／ＨＺＳＭ－５基催化剂上Ｗ物种的价态及其在Ｈ２预还原过程中的动态行为进行了表征研究．结果表明，由碱性前驱液制备的Ｗ／ＨＺＳＭ５催化剂在１０７３Ｋ、Ｈ２预还原条件下只能还原产生一类主要Ｗ物种，Ｗ５＋；而由酸性前驱液制备的Ｗ－Ｈ２ＳＯ４／ＨＺＳＭ－５催化剂在相同反应条件下则可还原产生两类共存的Ｗ物种，Ｗ５＋和Ｗ４＋．关联到在相同的甲烷脱氢芳构化（ＤＨＡＭ）反应条件下Ｗ－Ｈ２ＳＯ４／ＨＺＳＭ－５对ＤＨＡＭ反应的催化活性比Ｗ／ＨＺＳＭ－５高得多的实验事实，可以推断，ＤＨＡＭ反应活性与催化剂上较高价态Ｗ物种（Ｗ５＋）的浓度并不存在顺变关系，而与Ｗ４＋物种的浓度则密切相关

Spectroscopic characterization of methyl orange degraded by Fe-Cu iron internal electrolysis

应用紫外-可见光谱(uV-VIS)、质谱(MS)和电子顺磁共振(EPr)对甲基橙印染废水在fE-Cu铁内电解中的变化进行跟踪表征.研究结果表明,PH=3时,甲基橙在fE-Cu(质量比1∶1)和fE-Cu-Mn(质量比1∶1∶0.05)铁内电解体系中随着反应时间的增加在400—600nM区域uV-VIS吸收峰面积逐渐减少;fE-Cu-Mn(质量比1∶1∶0.05)吸收峰迅速蓝移至350—550nM区域,且吸收峰面积也逐渐减少.MS正负离子模式测得甲基橙准分子离子峰强度逐渐减小,但相应还检测到由于甲基橙分子断裂引起的逐渐变多的诸如芳香类和苯环裂解后共轭二烯物质的碎片信息.EPr检测到fE3+、fE2+的信号略有增加,在fE-Cu-Mn(质量比1∶1∶0.05)中Mn2+的6条超精细结构谱峰由弱转强.这些研究表明,在fE-Cu铁内电解中甲基橙降解的原因之一是氧化还原反应破坏发色基团,即偶氮双键的消失,引起甲基橙溶液脱色;另一原因是在微电场中,甲基橙分子断裂为更小质荷比的分子离子碎片而引起甲基橙脱色降解,这些研究结果为探索甲基橙溶液在铁内电解中脱色、降解机理提供有力的理论依据.The change of methyl orange in Fe-Cu iron internal electrolyzer was examined by UVVi S,MS and EPR.The results showed that UV-Vi S absorption peak in the range of 400—600 nm decreased with the increase of the reaction time in Fe-Cu( mass ratio 1 ∶ 1) and Fe-Cu-Mn( mass ratio 1 ∶ 1 ∶ 0.05) iron internal electrolyzer when the solution p H was 3.Positive and negative ion mode MS displayed that the quasi-molecular or ion peaks of methyl orange gradually decreased,but the fragments produced by the degradation of methyl orange were detected.EPR signals assigned to Fe2 +and Fe3 +increased slightly and the six fine peaks assigned to Mn2 +changed from weak to strong signal.These results indicated that one of the degradation routes of methyl orange is that the azo double bond was destroyed by oxidation-reduction reaction in Fe-Cu iron internal electrolyzer,which results in the decoloration of methyl orange.Another route was that in weak electric field,methyl orange was broken down to smaller fragments with lesser m / z.It is helpful to explore the efficiency of catalytic degradation and the degradation mechanism in the decoloration of methylorange in iron internal electrolyzer.福建省高校产学合作科技重大关键资助项目(2012H6008); 福州市科技计划项目(2013-G-92)资

Structural Recombination of Polymethylsilicone Induced by Laser Plasma

[中文文摘]将脉冲激光束在惰性气氛中溅射石墨产生的等离子体,与一维链状聚甲基硅氧烷的蒸气束流反应 ,在产物中通过真空升华和重结晶分离出了两种单晶,经X射线衍射测定为具有 (CH3SiO1.5) n(n =8,10 )组成的硅氧烷,它们均具有多面体的三维笼状构型 .通过色 -质联用还检测到其它硅氧烷化合物,其中某些产物已表征为二维多环的构型.反应结果表明,经由激光等离子体的碰撞和能量传递,反应物的链状结构发生解离和进一步反应,经结构重组形成了多种不同组成和构型的产物。[英文文摘]A special synthetic reaction has been developed, in which vapor of the reactant interacts with the high temperature plasma generated by laser ablating a graphite target. By selecting chained methylsilicone as reactant, a series of methylsilsesquioxanes products with various structural configurations have been obtained. Among them, two products, which were separated by sublimation in high vacuum and recrystalization, were characterized by X-ray crystal diffraction as (CH_3SiO_ 1.5)_n (n=8,10). Both of them are found to have three-dimensional cage structure.In addition,other products with double ring structure were detected by GC-MS analysis.The results demonstrate the potential application of the synthetic reaction.In the reaction described in this article,resulting from the collision and energy-transfer of the laser plasma,chain structure of the reactant dissociated and recombined to give the cage and ring structure of the product.国家自然科学基金重大项目(29890210)资助课

关注手性药物:从“反应停事件”说起

自从20世纪60年代发生"反应停"事件以来,药物手性的研究在新药研发领域引起了极大关注。手性异构体在生物体中可能表现出截然不同的药理、药物动力学、代谢和毒理活性等。近年来结合手性光谱的手性高效液相色谱(HPLC)技术在手性药物的分析、测定和分离等方面得到广泛应用,这对于手性药物对映体含量的检测和质量控制至关重要。国家自然科学基金(21571070,21273175,51772289)国家基础科学人才培养基金(J1310024)广东省自然科学基金(2018A030313193)广州市科学研究计划重点项目专题(201804020019

茶叶中茶多酚的吸附分离提取

研制了聚酰胺/硅胶负载型吸附剂并用于提取茶叶中的茶多酚。该吸附剂对茶多酚的吸附能力与硅胶的平均孔径和聚酰胺的负载量有关，硅胶平均孔径以12-13nM为宜；聚酰胺的担载量以10~20WT%效果最佳。该吸附剂对茶多酚的提取率约12%；制品纯度为85%─90%可直接用于食品加工工业