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1.
陈寿  吴守国  蒲国刚  汪尔康 《色谱》1992,10(3):130-133
 〕设计和研制了多工作模式的液相色谱电化学检测系统,主要包括一个多工作模式的电化学流通池和一个双恒电位仪。检测系统具有四种单双工作电极模式:壁面射流型、薄层型、双电极串行和平行相对型,既能用于定量分析工作,也能用于动力学研究。系统使用方便,灵敏度高,稳定性好。  相似文献   

2.
化学发光与色谱联用具有选择性好、灵敏度高等优点,应用广泛.本文主要介绍近三年来化学发光包括鲁米诺、过氧草酸酯、Ru(bipy)33 、无机等体系作为液相色谱柱后检测及含氮、含硫化合物气相化学发光等体系作为气相色谱柱后检测的现状.  相似文献   

3.
陈寿  吴守国  蒲国刚  汪尔康 《色谱》1992,10(6):326-328
 ]从理论上导出了薄层池的电极响应电流方程式。电极响应与流动相流速的关系为ip∝u0.332,与理论预测基本吻合。电极响应与池通道厚度有关,池通道越薄,电极响应越大。单电极薄层池工作方式用于分离和检测止痛药类化合物,分离效果好,灵敏度高,m-APAPSAm和Phen的检测限分别为1ng,4ng和4ng。  相似文献   

4.
采用高效液相色谱/串联质谱技术建立了快速鉴定Z型盐酸头孢吡肟原料药中E型异构体杂质的新方法。以乙腈-醋酸盐缓冲溶液(4∶96)为流动相经C18柱分离,通过高分辨电喷雾串联质谱在线检测,获得了相关的色谱和质谱信息。在所建立条件下,Z型盐酸头孢吡肟及其E型异构体杂质获得了有效分离,保留时间分别为5.22 m in和14.60 m in,同时它们的二级质谱及裂解方式呈现明显差异。本法能在无对照品情况下,快速、准确地分离鉴定盐酸头孢吡肟原料药中的Z/E异构体。  相似文献   

5.
新药研发、蛋白质组学分析、中药有效成分分析等前沿领域的快速发展,对分析检测方法的灵敏度、样品通量等提出了更高的要求,色谱分析技术面临着新的严峻挑战。作为色谱技术的核心,高效快速、高选择性的新型色谱柱开发是当前研究的热点之一。有机聚合物整体色谱柱因具有制备简单、通透性好、耐酸碱性能强、特别适合复杂样品的快速分离分析等优点,有望克服传统色谱分离介质的不足而备受关注。近年来分析对象越来越复杂,基于整体材料制备简单的特点,开发特殊功能化的新型整体色谱材料,成为分析科学及材料科学等领域研究者高度重视的方向之一。该文系统介绍了整体柱的发展史,并主要综述了有机聚合物整体色谱柱的发展及其功能化研究。  相似文献   

6.
氨基酸-铜配位化合物的紫外检测高效液相色谱研究   总被引:2,自引:0,他引:2  
研究了氨基酸-铜配位化合物的紫外检测反相高效液相色谱分离、测定方法,阐明了色谱分离、检测机理,探讨了流动相pH值、己基磺酸盐、铜离子、缓冲液浓度等对溶质保留和紫外检测灵敏度的影响,确定了最佳色谱分离、检测条件,并用于生物样品分析。  相似文献   

7.
采用快速高分辨液相色谱(RRLC)分离系统与QTRAP型及QTOF型MS/MS仪联用技术,通过考察尿液样本前处理方法,优化液相色谱条件和质谱检测参数,建立了用于尿液中代谢物分析的RRLC-MS方法.采用本方法对尿液浓度下的20种代表性代谢物进行了检测,考察了方法的灵敏度和精密度,证明本方法适用于尿液代谢组学的研究.对穿...  相似文献   

8.
局部麻醉药的反相色谱安培法检测   总被引:2,自引:1,他引:1  
周建迅  张丽静 《分析化学》1993,21(9):1031-1033
本文系统研究了普鲁卡因,利多卡因,丁卡因等3种局部麻醉药的液相色谱安培法检测行法,并与液相色谱光度法检测结果进行了比较。  相似文献   

9.
采用加速溶剂萃取-凝胶色谱净化建立了动物源性食品中胆固醇检测的高效液相色谱方法。结果表明,胆固醇浓度在1.0~40.0mg/L范围内线性关系良好,加标回收率为89.1%~99.8%,相对标准偏差为3.1%~7.8%。该方法准确、灵敏度高,适用于富含脂类的动物源性食品中胆固醇的检测。  相似文献   

10.
杨三东  李乃杰  马周  唐涛  李彤 《色谱》2021,39(10):1065-1076
小型化是液相色谱分离技术发展的重要趋势之一,包括仪器外形尺寸的小型化、分离材料粒径的小型化以及色谱柱内径的小型化。色谱柱内径的减小能够降低样品和流动相的消耗,具有更高的质量灵敏度,特别适合用于复杂样品体系的分离分析。纳升液相色谱一般是指使用内径小于100 μm的毛细管色谱柱,流速范围在每分钟几十至几百纳升的色谱技术。由于流速很低,色谱柱体积很小,柱外效应显著,因此对色谱仪器系统各个模块的性能以及系统柱外效应的优化提出了较高的要求。纳升液相色谱的输液装置需要能够准确稳定地输送纳升级流速,具有梯度输液模式,且拥有一定的耐压能力,以适应不同规格的色谱柱类型;进样装置需要能够进行准确重复的进样过程,进样体积及进样方式适合毛细管色谱柱,同时不产生明显的柱外效应;检测装置需要具有较高的灵敏度,且具有较小的柱外扩散;管路与连接系统需要稳定、可靠、易操作,并能够最大限度地减小柱外体积,适配纳升级流速。鉴于目前大多数纳升液相色谱系统与质谱检测器联用,因而本文主要从输液装置、进样装置、管路与连接3个方面对相关技术领域的研究论文、技术专利以及仪器厂商的宣传文件等进行了检索与归纳,综述了这些模块的技术路线与研究进展,同时简要介绍光学吸收型检测装置的优化思路与研究进展,并对部分商品化的纳升液相色谱系统进行了对比。  相似文献   

11.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

12.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

13.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

14.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

15.
针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。  相似文献   

16.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。  相似文献   

17.
In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.  相似文献   

18.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

19.
袁丽秋 《化学教育》2006,27(5):8-10
面对日益枯竭的能源危机,氢能是一种洁净、最有前景的替代能源。目前在各种制氢的方法中光催化分解水制氢的研究最多,光解水过程中催化剂最关键,本文对利用太阳能光解水的途径、提高光催化反应效率以及光催化剂的开发研究进行了综述。  相似文献   

20.
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