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1.
灰色理论在液相色谱保留值研究中的应用   总被引:13,自引:4,他引:13  
周申范  刘敏 《分析化学》1993,21(10):1126-1130
本文应用灰色理论中的GM(1,1)模型,对液相色谱中的Ф和k'的关系进行了研究,其结果达到用Schoenmakers公式和卢佩章公式预测及计算k'的水平。结果指出:灰色理论完全适用于对色谱保留问题的研究,其方法也这无全能满足实际工作中的应用。  相似文献   

2.
色谱保留值参数与灰色模型参数的关系   总被引:2,自引:0,他引:2  
唐婉莹  周申范  杨凌霄 《色谱》1998,16(2):95-99
用数学方法对灰色GM(1,1)模型与色谱中表述k′和φ关系的A,B值间的参数关系进行了推导,得出了两者间的函数关系式,从而预测了化合物的出峰位置以及各种混合组分分离分析的可能性,并对实验数据进行了检验,提出了一个获得适当的修正关系式的方法。结果表明:灰色GM(1,1)模型完全适合于对色谱参数值问题的研究。  相似文献   

3.
傅若农 《色谱》1992,10(1):41-42
从80年代初交联毛细管柱和大内径厚液膜毛细管柱的问世,显示了毛细管色谱法的突出优点,从而以毛细管柱逐步取代填充柱成为必然趋势。气相色谱法从1959年开始用于火炸药分析,从80年代初起把毛细管气相色谱用于火炸药污染物的分析以来,气相色谱法已成为火炸药分析十分有用的工具。根据我们多年的研究认为毛细管气相色谱法在很多情况下优于填充柱气相色谱法。  相似文献   

4.
本文根据气相色谱柱前,柱后蒸汽压的变化,通过对含不同碳原子的6类化合物于不同温度下蒸汽压的研究,提出采用气相色谱法时组分的蒸汽压必须高于15-746Pa,容量因子k^1必须在0.2-20之间。运用相应碳链长度(CCCL)的概念,通过固定相特性参数(Vg(7)和A1)解决了一定温度下“什么组分可从气相色谱柱中流出?“的预测问题。结合检测器特性得出是保留值太大限制了组分采用气相色谱法,阐明了只要组分能  相似文献   

5.
气相色谱灰色分析体系中未知组分保留指数的预测   总被引:4,自引:3,他引:1  
提出在部分组分已知的气相色谱灰色体系中,利用已知组分的保留指数和保留时间推算死时间和正构烷烃的保留时间,再计算未知组分保留时间的方法,结果显示,在已知组分不是太少的情况下,该方法计算的死时间和正构烷烃的保留时间与实验值吻合,预测的保留指数也有较高的精度.  相似文献   

6.
王恩琪  李佩芳 《色谱》1988,6(6):370-372
硝化甘油(NG)、二硝基甲苯(2,6-DNT和2,4-DNT)、三硝基甲苯(α-TNT)及二甲基二苯脲(C)是火药中最常见的组分。这些组分可用气相色谱法(GC)进行分离测定,但因NG的热稳定性较差,结果的精确度较差。对上述组分较有效的分析方法是高效液相色谱法(HPLC),因此法一般是在室温下进行,可避免NG等爆炸性组分的热分解。 HPLC分析火药组分在国内外早有报道。但国内做的工作不多。近年来我院开始应用HPLC分析火炸药组分。  相似文献   

7.
果蔬中107种残留农药的气相色谱-质谱检测方法   总被引:45,自引:12,他引:33  
采用毛细管气相色谱-质谱法对果蔬中107种残留农药检测进行了系统研究,考察了被测组分在不同极性毛细管色谱柱上的保留时间值,对比了不同前处理技术对检测结果的影响,确定了气相色谱-质谱检测农残初筛离子选择原则,规定了气相色谱-质谱确证被捡出农药应符合的条件。  相似文献   

8.
张维冰  史景江  吴也平 《色谱》1994,12(4):234-237
本文以统计热力学的观点,对流动相和固定相同时采用定标粒子理论处理,得到了描述分子间相互作用与k'间定量关系的关联方程,并对该方程加以实验验证及讨论。  相似文献   

9.
在Godon模型的基础上,应用pH函数导数峰值法和多点标准加入法来测定酸碱组分的pK值及其含量。在T'~pH图形上,峰位对应于组分的pK值,峰高正比于组分的浓度。  相似文献   

10.
烯烃在Ag柱上顶替置换色谱机理的研究   总被引:1,自引:1,他引:0  
陆婉珍  龙义成  陶学明 《色谱》1996,14(5):327-330
选择环己烯、苯或甲基叔丁基醚(MTBE)作为高效液相色谱法(HPLC)流动相改性剂、正己烷为流动相时,吸附在银型磺酸键合硅胶固定相上的烯烃与流动相改性剂之间存在顶替置换作用,即烯烃的容量因子k'的对数与改性剂浓度[Bm]的对数间有很好的线性关系。由关联直线的斜率p可获得烯烃置换改性剂的计量关系。但在不同流动相体系下,顶替置换过程不尽相同。在流动相改性剂浓度低于一定值时,内烯烃混合物与α-烯烃混合物都能与饱和烃分离并以不同的k'流出,各自lgk'值与lg[Bm]值之间也有线性关系。  相似文献   

11.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

12.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

13.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

14.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

15.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

16.
Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.  相似文献   

17.
用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.  相似文献   

18.
19.
A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu0 as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than CuI in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).  相似文献   

20.
(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C60, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.  相似文献   

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