流动注射在线液-液萃取火焰原子吸收法测定水中痕量铅

提出了一种流动注射在线液－液萃取火焰原子吸收直接测定水中痕量铅的分析方法。实验以APDC为螯合剂,用MIBK为萃取剂,研究了在线萃取中各种实验参数、酸度条件的影响,考察了共存元素的干扰。方法的RSD（n=12)为2．7％,测定检出限为3．1μg/L,回收率为96％－106％。     

重力分相器用于流动注射—液—液萃取—原子吸收光谱法间接测定硝酸根

应用一种新型的四通道重力分相器，通过实验，选定了流动注射－液－液萃取－原子吸收间接硝酸根的最佳力学待人接物仪器参数，方法的精密度（ＲＳＤ）和检出限分别为１．９％和０．０２８ｍｇ／Ｌ，测定速度为２５样／ｈ，用本系统水样中的硝酸根和亚硝酸根，标准加入顺收率为１００－１１０％。     

固相微萃取-气相色谱联用技术测定水相中的邻苯二甲酸二(2-乙基)己酯

利用顶空固相微萃取与气相色谱联用技术（HS－SPME－GC）以富勒烯聚二甲基硅氧烷（PSO－C60）固定相处制萃取头分析了塑料浸取液中的邻苯二甲酸二（2－乙基）己酯（DEHP），并对萃取温度、离子强度、吸附时间和热解析时间进行了研究。结果显示，该方法的线性范围在5μg/L－500μg/L，检测出了为2．8μg/L，相对标准偏差为4．8％（n=6).     

血、尿中氯硝西泮及其代谢物7-氨基氯硝西泮的GC-ECD法检测

报道了血、尿中氯硝西泮及其代谢物7－氨基氯硝西泮的GC－ECD检测方法。苯－异戊醇碱性条件下（pH10.8）液－液萃取，灵敏度较高，氯硝西泮和7－氨基氯硝西泮的检测限（LOD）分别为3．2ng/mL及1．7ng/mL。线性范围5－300ng/mL，RSD5．3％。     

高效液相色谱法测定烟草料液中的糖、甘油和丙二醇

研究了用高效液相色谱法测定烟草料液样品中糖、甘油和丙二醇的方法。烟草料液用Sep-Park-C18固相萃取小柱预分离，以Waters Surar-Pakl钙型阳离子交换柱为固定相，0．05g/L EDTA钙钠水溶液为流动相，示差折光仪为检测器，一次进样测定烟草料液样品中的糖、甘油和丙二醇。线性范围为0．005－5g/L,检测限在1．5－2．5mg/L之间，相对标准偏差为0．89％－1．3％，标准回收率在96．0％－103％之间。方法用于几种烟草料液样品测定，结果令人满意。     

饲料中克伦特罗和沙丁胺醇分离方法的研究

研究了用液-液萃取和固相萃取两种方法同时分离饲料中克伦特罗和沙丁胺醇．液．液萃取法中，采用乙酸乙酯 正己烷 异丙醇混合溶剂，克伦特罗和沙丁胺醇萃取率分别可达85．20％、83．00％：固相萃取法中，采用Amberlite XAD-2大孔吸附树脂，效果较液．液萃取更好。萃取率为91．25%和86．10％．两种分离方法用于饲料中克伦特罗和沙丁胺醇的测定。结果满意．     

用吐温80—盐—水液—固萃取体系从兔肌中分离纯化乳酸脱氢酶

用吐温８０－盐－水液－固萃取体系从兔肌中分离纯化乳酸脱氢酶＊柳畅先邓江天雷锦桂游文淑李步海（中南民族学院化学系武汉４３００７４）关键词液－固萃取吐温８０乳酸脱氢酶中图分类号Ｏ６５８．２非有机溶剂液－固萃取体系是一种新的萃取体系，其特点之一是聚合物固相...     

一种新的FI－液液萃取重力分相器的设计及其分析性能研究

本文设计了一种适用于各种萃取体系并能与原子光谱仪和分光光度计联用的ＦＩ液液萃取重力分相器．用该分相器分别研究了ＦＩ－ＭＩＢＫ萃取－ＦＡＡＳ测定金和ＦＩ－ＣＣｌ４萃取－分光光度法测定碘的分析性能．结果表明，该分相器操作简单，分相完全，是一种较理想的重力分相器     

一种在线液—液萃取微型多用分相器的设计和应用：IV.流动注射液— …

设计了在线液－液萃取多用重分布相器及相应流动注射流路系统与ＩＣＰ－ＡＥＳ法联用。具有良好的分析性能，通过对矿石中某些重稀土元素在硝酸介质中被ＴＢＰ萃取的应用研究表明钇，镱，铒的检出限（３σ）分别为６．８ｎｇ／ｍＬ，０．２ｎｇ／ｍＬ和１．５ｎｇ／ｍＬ，精密度（ＲＳＤ％）分别为０．２４，０．４７和１．８，进样频率为２５－３０个／ｈ。     

一种新的FI—液液萃取重力分相器的设计及其分析性能研究

本文设计了一种适用于各种萃取体系并能与原子光谱仪和分光光度计联用的ＦＩ液液萃取重力分相器。用该分相器分别研究了ＦＩ－ＭＩＢＫ萃取－ＦＡＡＳ测定金和ＦＩ－ＣＣｌ４萃取－分光光度法测定碘的分析性能。结果表明，该分相器操作简单，分相完全，是一种较理想的重力分相器。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

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.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

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.