溴化十二烷基吡啶的吸附和表面胶团化对二氧化硅悬浮液稳定性的影响

研究了阳离子表面活性剂溴化十二烷基吡啶（ＤＰＢ）的吸附和表面胶团化对二氧化硅（ＣＡＢ－Ｏ－ＳＩＬ）悬浮液稳定性的影响，以及加入电解质的效应．结果表明：ＤＰＢ在ＣＡＢ－Ｏ－ＳＩＬ上的吸附等温线呈双平台（或ＬＳ）型，溴化钠（０．１ｍｏｌ／Ｌ）的存在使吸附等温线向低浓区移动，第二平台的饱和吸附量增大，但基本不影响第一平台的吸附量，这些结果都与涉及形成表面胶团的二步吸附模型相符．当ＤＰＢ浓度很低时，ＣＡＢ－Ｏ－ＳＩＬ悬浮液的稳定性随ＤＰＢ浓度的增大而下降；当ＤＰＢ浓度增至ｓｍｃ（临界表面胶团浓度）附近时，悬浮液稳定性急剧提高．ＮａＢｒ的存在，并不影响上述悬浮液稳定性规律．利用表面活性剂的二步吸附和颗粒相互作用模型，并结合ＤＰＢ吸附等温线的研究结果，可以合理地解释ＣＡＢ－Ｏ－ＳＩＬ悬浮液稳定性的实验结果．     

表面活性剂和聚乙烯吡咯烷酮在ZrO2上的吸附对其悬浮体稳定性的影响

研究了水溶液中十二烷基苯磺酸钠（ＳＤＢＳ）、溴代十四烷基吡啶（ＴＰＢ）和聚乙烯吡咯烷酮（ＰＶＰ）在ＺｒＯ２上的吸附及对ＺｒＯ２水悬浮体稳定性的影响。结果表明：ｐＨ＝２．４时ＳＤＢＳ在ＺｒＯ２上的吸附等湿线为ＬＳ型，ｐＨ＝７．０时ＴＰＢ的吸附等温线为Ｓ型，吸附等温线与ＺｒＯ２粒子ζ电势变化同线有大体一致的关系。在最大吸附量时ＺｒＯ２粒子ζ电势较大，且吸附的表面活性剂离子形成大部分亲水基朝向水相的表面     

PNPAR—CTMAB光度法测定水中痕量阴离子表面活性剂

本文研究了对硝基偶氮间苯二酚（ＰＮＰＡＲ）与溴化十六烷基三甲铵（ＣＴＭＡＢ）形成的离子缔合物ＰＮＰＡＲ－ＣＴＭＡＢ作显色剂与阴离子表面活性剂（ＡＳ）的显色反应，发现在ｐＨ１３．０的ＮａＯＨ介质中，ＡＳ能定量置换出ＰＮＰＡＲ－ＣＴＭＡＢ中的ＰＮＰＡＲ，而使其最大吸收波长６３０ｎｍ处吸光度下降，阴离子表面活性十二烷基苯磺酸钠（ＳＤＢＳ）和十二烷基磺酸钠（ＳＤＳ）的ε值分别为３．５×１０＾４，５．８×１     

用表面增强拉曼光谱研究BMAT对不锈钢的缓蚀机理

应用表面增强拉曼散射光谱（ＳＥＲＳ）技术，研究０．５％ＨＣｌ体系中缓蚀剂在１８－８不锈钢表面的吸附。谱图是在不锈钢表面电沉积不连续Ａｇ颗粒条件下测得的。缓蚀剂ＢＭＡＴ通过电极表面与缓蚀剂中的Ｎ原子，以及苯并咪唑环的共轭大π键形成化学吸附，ＢＭＡＴ斜卧于电极表面。其烯丙基起到空间的阻碍的作用。     

聚（β－羟基丁酸酯）／聚双酚A羟基醚共混体系相容性及结构的研究

ＤＳＣ和ＦＴＩＲ测试表明，结晶／非晶共混体系聚（β－羟基丁酸酯）（ＰＨＢ）／聚双酚Ａ羟基醚（ＰＢＨＥ）是部分相容的．熔融结晶退火可以大大提高共混物的结晶度，增加其相容性，７５／２５组分ＰＨＢ相结晶度最大，５０／５０组分（０２０）、（１３０）晶面微晶尺寸最大．ＳＡＸＳ研究表明，纯ＰＨＢ的中间层约为１．５ｎｍ，片层厚约４．０ｎｍ；共混物的中间层在２．０ｎｍ左右，片层厚在５．０—７．２ｎｍ之间，５０／５０组分片层最厚．７５／２５组分晶相和非晶相的密度差最大．     

在表面活性剂存在下用5—Br—PADAP吸光光度法测定汞

研究了在阴离子表面活性剂ＳＤＳ存在下,用５－Ｂｒ－ＰＡＤＡＰ测定汞的最佳条件。试验表明,在硼砂－盐酸缓冲介质中,ＰＨ为８．３５￣１０．４０时,络合物的最大吸附波长为λｍａｘ＝５６２ｎｍ,表观摩尔吸光系数为１．１２×１０＾５,络合物的组成为Ｈｇ（Ⅱ）：５－Ｂｒ－ＰＡＤＡＰ＝１：２,线性范围为０￣３５μｇ／２５ｍｌ．方法体系简单,操作方便,是目前光度法测定痕量Ｈｇ（Ⅱ）灵敏度较高的方法之一。     

盐酸溶液中阴离子表面活性剂在铝表面上的吸附

用失重法研究了盐酸溶液中阴离子表面活性剂十二烷基磺酸钠（ＤＳＡＳＳ），十二烷基苯磺酸钠（ＤＢＳＡＳ）以及十二烷基硫酸钠（ＳＤＳ）在铝表面上的吸附作用，提出这种吸附作用与铝的失重量有关，且符合Ｌａｎｇ－ｍｕｉｒ方程，计算出吸附热，吸附熵和吸附自由能等热力学参数。认为这种吸附主要靠静电作用，根据接触角的变化讨论了阴离子表面活性剂分子在铝表面上的吸附取向。     

Ag2CO3溶胶中PABA表面增强拉曼光谱及增强机制的探讨

首次观测到Ａｇ２ＣＯ３溶胶体系中的吸附分子（对氨基苯甲酸ＰＡＢＡ）表面增强拉曼散射（ＳＥＲＳ）效应特强，该体系对ＰＡＢＡ的增强程度比Ａｇ胶还强。同时，分别向该体系加入少量的Ｓ２Ｏ３，Ｆｅ（ＣＮ）６，Ｈ２Ｏ２和ＮＯ３－溶液后，观测其对ＰＡＢＡ的ＳＥＲＳ谱带强度的影响，探讨该体系的增强机制。结果表明，胶体表面的Ａｇ＋或Ａｇδ＋是该体系的ＳＥＲＳ活位吸附点，而表面络合物对其ＳＥＲＳ起到一定的作用。     

载锰活性碳纤维SACF-Mn的制备及对乙基硫醇的吸附性能研究Ⅱ.-SACF-Mn对乙基硫醇的吸附性能研究

研究了ＳＡＣＦ－Ｍｎ对乙基硫醇的吸附性能。发现ＳＡＣＦ-Ｍｎ对乙基硫醇的吸附性能与ＳＡＣＦ－Ｍｎ的制备条件密切相关．ＳＡＣＦ－Ｍｎ对乙基硫醇的吸附，特别对汽油中硫醇的吸附性能优异于ＳＡＣＦ．     

AB—8树脂对罗汉果皂甙的吸附

本文初步研究了大孔吸附树脂ＡＢ－８对罗汉果皂甙的吸附性能，比较了１５℃和６５℃下的吸附速度，获得了在ＳＶ２、ＳＶ５、ＳＶ８三种空速下的穿漏吸附量。     

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%.     

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.     

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.     

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.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

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.