一些无机盐对甲烷的液相选择催化氧化

考察了无机盐Ｃｒ２（ＳＯ４）３，ＣｄＳＯ４，ＦｅＳＯ４，ＶＯＳＯ４，Ｃｅ（ＳＯ４）２，ＭｎＳＯ４，ＳｎＣｌ４和ＨｇＳＯ４在浓硫酸介质中对甲烷的催化活性，发现ＭｎＳＯ４，ＳｎＣｌ４和ＨｇＳＯ４对甲烷氧化有活性，在此基础上考察了ＨｇＳＯ４体系中气液体积比，温度，浓度，反应时间以及硫酸浓度地反应活性的影响，认为反应按亲电取代反应机理进行。     

阻抑褪色光度法测定痕量汞

提出一种测定痕量汞的新的光度法。该法基于Ｈｇ（Ⅱ）对Ｈ２Ｏ２与离子缔合物ＡｇＣｌ·ＰＶＡ·Ａｇ~＋·Ｆｉｎ~－褪色反应的抑制效应,该离子缔合物对应于聚乙烯醇存在下Ｆａｊａｎｓ（法扬斯）法的终点,线性回归方程△Ａ＝０．０２＋ ４．０×１０~（－３）Ｃ_（Ｈｇ（Ⅲ））（μｇ／Ｌ）,相关系数ｒ＝０．９９９２,Ｈｇ（Ⅱ）浓度在４．０～２０．０μｇ／Ｌ范围内服从比耳定律,检出限０．０４μｇ／Ｌ。该法用于废水样中Ｈｇ（Ⅱ）的测定,结果与双硫腙法结果相符。     

水杨醛二缩邻苯二胺汞（Ⅱ）配合物为载体的高选择性碘离子电极的研究

研究了希夫碱金属「Ｃｏ（Ⅱ）、Ｍｎ（Ⅱ）、Ｚｎ（Ⅱ）、Ｈｇ（Ⅱ）」配合物为载体的阴离子选择性电极,结果表明,水杨醛二缩邻苯二胺汞对碘离子具有高的选择性,且电极呈现反Ｈｏｆｍｅｉｓｔｅｒ行为,其选择性次序为：Ｉ〉ＳＣＨ〉Ｂｒ〉ＣｌＯ４〉Ｃｌ〉ＮＯ２〉ＮＯ３〉ＳＯ４＾２－。该电极响应速度快,具有良好的稳定性,使用寿命在三个月以上,用交流阻抗,紫外可见光谱技术研究了电极的响应机理并将电极用于药品分析,结     

等离子体光谱法同时测定羟基磷灰石中的As,Hg方法研究

等离子体光谱法同时测定羟基磷灰石中的Ａｓ、Ｈｇ方法研究胡明芬童式国（四川大学分析测试中心成都６１００６４）关键词砷汞等离子体光谱法氢化物发生羟基磷灰石［Ｃａ５（ＰＯ４）３（ＯＨ），简称ＨＡ］是一种优良的生物活性材料，在医学上主要是制备各种人工骨制品，...     

新显色剂—6硝基—苯并噻唑重氮氨基偶氮苯与汞的显色反应及其应用研究

研究了新显色试剂６－硝基－苯并噻唑重氮氨基偶氮苯与Ｈｇ（Ⅱ）的显色反应。在乳化剂ＯＰ存在下，于ｐＨ１０．０的缓冲溶液中，Ｈｇ（Ⅱ）与显色剂形成１：２的稳定红色络合物。络合物的λｍａｘ＝５１５ｎｍ，其表观摩尔吸光系数为１．５３×１０＾５Ｌ·ｍｏｌ＾－１·ｃｍ＾－１，Ｈｇ（Ⅱ）含量在０￣５μｇ／１０ｍＬ范围符合比尔定律，样品分析结果令人满意。     

二茂铁亚胺及其环汞化合物的薄层色谱及紫外—可见,红外光…

通过测定Ｒｆ值对比研究了二茂铁亚胺及其环汞化合物的色谱亲和性，发现环汞化合物比未汞化的二茂铁亚胺具有较高Ｒｆ值，并用Ｎ→Ｈｇ分子内配位作用给予解释，分析取代基效应表明，亚胺氮上电子密度越高，Ｒｆ值越小，紫外可见光谱表明，环汞化合物人子中存在有Ｎ→Ｈｇ分子内配位作用，研究了Ｎ－Ａｒ环和亚胺碳上的取代基效应对紫外光谱的影响，与Ｎ－Ａｒ环上无取代基时相比，π→πＣＴ跃进带的最大吸收波长移动值△λｍａｘ和     

ICP—AES用于铋系超导体块材及薄膜的组分分析

本文研究了一个简便，快速的用ＩＣＰ－ＡＥＳＢｉ（Ｐｂ）ＳｒＣａＣｕＰｂＯ，Ｂｉ（Ｐｂ，Ｓｂ）Ｓｒ－ＣａＣｕＯ，Ｂｉ（Ｐｂ，Ｙ）ＳｒＣａＣｕＯ超导体块材及薄膜中Ｂｉ，Ｐｂ，Ｓｂ，Ｙ，Ｓｒ，Ｃａ，Ｃｕ含量的方法。样品溶解在５０％ＨＣｌ及５０％ＨＮＯ３的混合酸中，直接引入等离子体光谱中进行测定。对共存元素的相互干扰及基片成分的干扰进行了研究。分析了大量样品，给出了各组分的挥发情况及Ｐｂ的挥发量与烧结温度     

线型异核三金属M—E—M（M=Mo,W;E=Hg,Zn）化合物的研究…

研究了含汞三金属化合物「η－ＲＣ５Ｈ４（ＣＯ）３Ｍ２「Ｈｇ（Ｍ＝Ｍｏ，Ｗ；Ｒ＝Ｍｅ，Ｅｔ，ＣＯ２Ｍｅ，ＣＯ２Ｅｔ）与锌粉的置换反应，发现当取代基Ｒ为给电子的Ｍｅ和Ｅｔ时底物不发生反应，而取代基Ｒ为拉电子的ＣＯ２Ｍｅ和ＣＯ２Ｅｔ时，则底物中的汞可被锌置我。     

荧光光谱法测定工业废水中痕量汞的研究

利用汞（Ⅱ）在适量一乙醇和β－环糊精存在下对四（４－三甲铵苯基）卟啉（ＴＡＰＰ）的荧光熄灭作用,提出了测量汞的高灵敏荧光光度新方法,拟定条件下的荧光激发峰λｅｘ＝４１４ｎｍ,荧光发射峰λｅｍ＝６４６ｎｍ,荧光熄灭值△Ｆ与Ｈｇ（Ⅱ）的质量浓度在０～３μｇ／２５ｍＬ范围内呈线性关系。本法操作简便,不必加热,也无需催化剂,应用迅速且体系稳定。本法用于测定工业废水等样品中的痕量汞,与其它方法的结果吻合。     

MZrO3（M=Ba,Sr,Ca）水热合成中结构与反应活性的关系

ＭＺｒＯ_３（Ｍ＝Ｂａ，Ｓｒ，Ｃａ）水热合成中结构与反应活性的关系郑文君，庞文琴（吉林大学化学系，长春，１３００２３）关键词水热合成，ＭＺｒＯ_３（Ｍ＝Ｂａ，Ｓｒ，Ｃａ），结构，反应活性钙钛矿型复合氧化物ＭＺｒＯ３（Ｍ＝Ｂａ，Ｓｒ，Ｃａ）是重要的功能陶...     

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%.     

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.     

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.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.