点可迁图中的正则因子

设图G是一个K-正则连通点可迁图.如果G不是极大限制性边连通的,那么G含有一个(k-1)-因子,它的所有分支都同构于同一个阶价于k和2k-3之间的点可迁图.此结果在某种程度上加强了Watkins的相应命题:如果k正则点可迁图G不是k连通的,那么G有一个因子,它的每一个分支都同构于同一个点可迁图.     

微乳液增敏对硝基苯基荧光酮光度法测定人发中痕量镍

研究了微乳液介质中,在pH等于10.4时,镍与对硝基苯基荧光酮(p-NPF)显色生成稳定的1∶3配合物,在600nm处摩尔吸光系数为1.64×105L/(mol·cm),镍含量在0～0.7μg/mL范围内符合比耳定律,采用巯基葡聚糖凝胶分离富集,消除了共存离子的干扰,用所拟方法测定人发中的痕量镍,结果令人满意.     

香云多糖的分子表征和稀溶液性质研究

The polysaccharide of lentinus edodes and polytictus versicolor has been fractionated by repeated precipitation method.All fractions and the unfractionated samples have been characterized by rapid dynamic membrane osmometry. For its aqueous solution, the second virial coefficient A₂ decreases as the molecular weight increases. The relationship is A₂= 2 slope (MnRT)-1/2.Determination of the distribution curve by means of fractional precipitation. Separation of a polysaccharide into six fractiona by a fractional precipitation carried out. The distribu-tion-curve of integral and differential is obtained. After according to the modified Elias'cloud-point titration method and using an Abbe's refractometer to define the clou-point,^[6-]8it was found that water/acetone (89:11 by vo-lume) is a θ solvent for the polymer at 25±0.05 C. For θ conditions,the intrinsic viscosities were determined by capillary viscometry. Thus a monodispersed [n]-M relationship has been obtained: [n]_θ=2.59×10^-2M^0.509 From the result above the unperturbed dimensi on(r²_θ)^1/2 was found to be 4.7×10^-9M^1/2.     

Chromatographic Properties for Enantiomeric Separation of Amino Acid Derivatives on the Molecularly Imprinted Monoliths

Since their introduction in 1992 by Fréchet and Svec[1], monolithic supports as stationary phases in high performance liquid chromatography (HPLC) and capillary electrochromatography (CEC) have gained significant interest due to a number of unique properties. Their ease of preparation, high reproducibility, versatile surface chemistry and fast mass transport are advantageous in a variety of applications[2-4]. Separations in diverse chromatographic modes have been performed in either HPLC or CEC, showing their strong point for high-speed separations of biological and synthetic molecules[5-12]. Although a number of papers have been reported on the application of monolithic supports as chiral stationary phases in CEC and pressure-assisted capillary electrochromatography (p-CEC)[13-19], few reports have so far been published on chiral monolithic stationary phases for liquid chromatography[20].     

Preparation of A New Fiber by Sol-gel Technology in Solid-phase Microextraction （SPME）

The sol-gel technology is applied for the preparation of solid-phase microextraction (SPME) fiber. The fiber demonstrates high thermal stability, efficient extraction rate and the selectivity for non-polar or low-polar analytes. Efficient SPME-GC-FID analyses of benzenetoluene-ethylbenzene-xylenes (BTEXs) and low-polar halocarbon were achieved by the sol-gel coated DSDA-DDBT-TiO2 fiber. Some parameters of the SPME fiber for the determination of halocarbon in aqueous sample were investigated.     

示波极谱法测定电解锰用阳极板中锡

样品经硝酸分解，有硫酸钡共沉淀分离铅后，锡在硫酸氯化钠底液中，在峰电位－0．52V处产生良好的还原波，能直接测定电解锰电解锰用阳极板中锡。回收率为98．0％－101．6％，相对标准偏差0．91％－2．98％，方法简便，快速，准确、优于容量法，已应用于工业分析。     

采用原位聚合法制备固相微萃取涂层的初步研究

采用一步原位合成法制备了新型有机多孔聚合物涂层，并对其进行了初步评价研究．观察了单体浓度对其所制备涂层的萃取容量的影响，并优化了合成浓度．同时，在分析水体基质中的苯系物时，证明了该涂层对苯系物等含苯环物质具有选择性吸附的能力．     

MPP/PER/APP系统阻燃的PA6/OMMT纳米复合材料的燃烧特性

以聚磷酸蜜胺(MPP)／季戊四醇(PER)／聚磷酸铵(APP)三元膨胀型阻燃剂(IFR)(其中P／PER／三聚氰胺(MA)的摩尔比为4．1／1．0／1．1)对聚酰胺6(PA6)／有机蒙脱土(OMMT)纳米复合材料(wOMMT=0．03)进行阻燃，测定了阻燃PA6／OMMT的极限氧指数(LOI)及垂直燃烧阻燃性(UL94)，以锥形量热仪(CONE)测定了材料诸多与火灾安全性有关的阻燃参数，包括释热速率、有效燃烧热、总释热量、质量损失速率、比消光面积及引燃时间等，并与PA6、阻燃PA6及PA6／OMMT进行了比较，用扫描电镜(SEM)观察了由CONE测试所得残炭的形态。     

α－一铌二钼十五钨磷杂多酸盐的合成和性质研究

合成了通式为α－Ｍ＿（７－ｘ）Ｈ＿ｘ［Ｐ＿２Ｗ＿（１５）Ｍｏ＿２ＮｂＯ＿（６２）］·ｘＨ＿２Ｏ［Ｍ＝Ｋ~＋，（ＣＨ＿３）＿４Ｎ~＋，（Ｃ＿２Ｈ＿５）＿４Ｎ~＋，（Ｃ＿４Ｈ＿９）＿４Ｎ~＋］的４种盐．用ＩＲ、ＵＶ吸收光谱、极谱、~（１８３）ＷＮＭＲ、ＸＰＳ和ＸＲＤ等方法对其进行了表征，确认三取代的位置是在Ｄａｗｓｏｎ结构的同一“极位”．研究了取代Ｗ原子数目对~（１８３）ＷＮＭＲ化学位移的影响，发现“极位”Ｗ原子的~（１８３）ＷＮＭＲ化学位移平均值与取代原子数目呈线性关系．     

N-取代苯基-2-取代-1,3-噻唑烷-3-甲酰胺的合成、结构及生物活性

为了寻找新的含噻唑杂环的先导化合物, 利用2-取代-1,3-噻唑烷与取代苯基异氰酸酯在三乙胺催化下发生偶合反应, 合成了17个N-取代苯基-2-取代-1,3-噻唑烷-3-甲酰胺化合物3, 并利用¹H NMR, IR, MS和元素分析对其结构进行了表征. 用X-ray单晶衍射测定了N-苯基-2-氧代-1,3-噻唑烷-3-甲酰胺(3a)的晶体结构. 初步生物活性试验结果表明, 在试验浓度下部分目标化合物具有一定的杀菌和杀虫活性.