氢化物发生辅助雾化火焰原子吸收法测定水中铅

研究了一种提高火焰原子吸收测定铅灵敏度的新方法——氢化物发生辅助雾化的火焰原子吸收法；方法采用硼氢化钠与铅(Ⅳ)在原火焰原子吸收雾化器喷口处反应生成氢化物，以提高火焰原子吸收法的雾化效率；采用重铬酸钾一酒石酸预处理体系，重铬酸钾氧化样品中铅(Ⅱ)为铅(Ⅳ)，酒石酸稳定铅(Ⅳ)的亚稳态化合物；对各种实验参数和干扰情况也进行了研究；方法操作简单、快速，灵敏度比通常的火焰原子吸收法提高了6．8倍；检出限(K=3，n=11)为6．64μg/L，线性范围为0．021～3．2mg／L；测定水样的回收率达94％～99％。     

茶多酚中微量铜的原子吸收光谱分析

叙述了干灰法消化样品后，利用原子吸收光谱仪测定茶多酚中微量铜的方法。该法的回收率在９０％￣１０５％之间；对同一样品进行６次平行测定，其相对标准偏差为３．９％，结果可靠，方法简便；可用于实际样品分析。     

交联壳聚糖富集分离冷原子吸收分光光度法测定环境水样中痕量无机汞

报道了采用不溶于酸碱的交联壳聚糖，以ＥＤＴＡ为络合剂性富集分离，冷原子吸收分光光度法直接测定环境水样中痕量无机汞的方法，并发分析的最佳条件进行了探讨。地分析实际水样，回收率为９４％－９８％；检测下限为７．８ｎｇ／Ｌ；相对标准偏差小于６％。     

用毛细管电泳同时分析饮料中合成色素和防腐剂

建立了饮料中合成色素与防腐剂的毛细管电泳分离、紫外吸收检测分析方法；详细研究了缓冲体系组成与浓度对分离效果的影响。在优化条件下，１１ｍｉｎ完成５种色素和２种防腐剂的分析，检测限为１５～５８ｍｇ／Ｌ；保留时间精度为０３９％～１１％；峰高测量精度为１４％～２９％；该法成功地用于实际样品的分析。     

甘薯中微量钙铁的原子吸收分光光度法测定

研究了用原子吸收分光光度法测定甘薯中的微量钙、铁的含量；采用高温灰化法对样品进行处理，并对40多种不同品种和不同种植地区的甘薯进行了实样测定和含量差异比较；对9个样品进行钙和铁的加标回收试验，测定的回收率在91％－107％之间，相对标准偏差RSD（n=9)分别为4．6％、5．4％，结果令人满意。     

石墨炉原子吸收分光光度法测定茶叶中的铅

采用石墨炉原子吸收分光光度法测定了产自福建等地茶叶中的铅含量。方法的线性范围为0—80μg/L，回收率达91．7％-101．5％，相对标准偏差1．47％-3．88％。茶样检测结果表明，铅合格率为92．0％；不同茶类铅含量前3位由高到低依次为绿茶，乌龙茶，红茶；各类茶铅含量平均值为1．069mg／kg。     

火焰原子吸收法测定癌细胞中的钙、镁、铜等金属元素

采用火焰原子吸收法直接测定一系列(食道、胃)癌细胞及其近旁的正常细胞中的钙、镁、铜等金属含量。结果表明，钙的变异系数为1．83％-4．19％，回收率为99．8％-104．0％；镁的变异系数为0．02％～1．18％，回收率为97．2％-98．5％；铜的变异系数为3．80％-6．68％，回收率为90．5％～99．7％；均得到较满意的结果，具有一定的参考价值。     

锆硼陶瓷材料中总硼分析方法研究

对锆硼陶瓷材料中总硼的分析方法进行了研究，采用硫酸和硫酸铵及重铬酸钾氧化两步溶解法分解样品，氮气载带硼酸三甲酯蒸馏分离硼与锆（氦气流速150mL/min水溶加热，NaOH溶液吸收），材料中成分为Zr粉＋B4C粉，Zr含量≥99％（ut），经阳离子交换法除去吸收液中Na后采用ICP-AES法测定硼。方法的相对标准偏差（n=6）小于2．0％；标准加入回收率为99％。     

火焰原子吸收光谱法直接测定食用菌中的铅和镉

采用火焰原子吸收法直接测定了食用菌中铅和镉的含量。方法灵敏、准确，测定时无须富集、萃取，操作简便，快速，铅和镉的相对标准偏差分别在3．3％～7．3％和3．1％～7．5％之间。回收率在94％～106％和95％～105％之间；检出限为0．016mg/L和0．008mg/L。     

磁性纳米TiO2/Fe3O4光催化复合材料的制备及性能

采用溶胶-凝胶法，在磁性Fe3O4表面包覆TiO2，制备了一种新型纳米TiO2/Fe3O4光催化复合材料．XRD，TEM对材料形态结构及包覆情况的分析，显示TiO2包覆在Fe3O4表面，形成平均尺寸为35～50nm的复合结构；UV-vis吸收曲线表明，复合材料对光的吸收出现红移，吸收强度增大；对染料废水光催化降解的模拟研究表明，该复合材料对活性艳红染料的脱色率达100％，是一种便于回收、可重复使用的高效光催化剂．     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

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.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

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.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

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%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

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.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

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.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

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.     

正丁胺对激光染料荧光谱影响的研究

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.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

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 Cu^I 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).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(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.