N—（4,6—二甲氧基嘧啶—2—基）—N‘—磷酰基脲类衍生物的及生？…

利用二氯磷酰基异氰酸酯与４，６－二甲氧基－２－氨基嘧啶的加成反应合成了中间体Ｎ－（４，６－二甲基嘧啶－２－基）－Ｎ’－二氯代磷酰基脲，Ⅰ与２倍的醇或胺反应得到对称双取代磷酸基脲类化合物Ⅱａ－Ⅱｉ，Ⅰ与１倍的受反应得到氯代磷酰基脲类化合物Ⅲａ－Ⅲｅ，再与Ⅰ１倍的醇反应则得到不对称双取代磷酰基脲类化合物Ⅳａ－Ⅳｇ。     

硫酸铵—水杨基荧光酮—乙醇体系萃取分离钼

研究了硫酸铵－水杨基荧光酮－乙醇体系萃取钼的行为及乙醇水溶液的分相条件，试验表明，作为萃取溶剂的乙醇，能萃取电中性螯合物又能萃取带电荷螯合物，当溶液ｐＨ１～２，能使Ｍｏ（Ⅵ）与Ｆｅ（Ⅲ），Ｃｕ（Ⅱ），Ｃｏ（Ⅱ），Ｍｎ（Ⅱ）分离。     

二—（2—乙基己基聚氧化烯烃）琥珀酸双酯磺酸钠的表面活性及应用

二－（２－乙基己基聚氧化烯烃）琥珀酸双酯磺酸钠的表面活性及应用姚传义吴金川何志敏＊（天津大学化学工程研究所天津３０００７２）关键词二－（２－乙基己基聚氧化烯烃）琥珀酸双酯磺酸钠，表面活性，反胶团酶反应，橄榄油水解１９９７－０９－１９收稿，１９９７－１...     

2－乙基己基膦酸单（2－乙基己基）酯从盐酸溶液中萃取Ga（Ⅲ）的机理

２－乙基己基膦酸单（２－乙基己基）酯从盐酸溶液中萃取Ｇａ（Ⅲ）的机理赵经贵，邢美君，刘宏（黑龙江大学化学系哈尔滨１５００８０）关键词溶剂萃取，镓，乙基己基膦酸单（乙基己基）酯２－乙基己基膦酸单（２－乙基己基）酯（Ｐ５０７，ＥＨＰ）在稀有元素、有色金属...     

1,9—双（1′—苯基—3′—甲基—5′—氧代吡唑—4′—基）壬二酮—（1,9）与三？…

研究了１，９－双（１′－苯基－３′－甲基－５′－氧代吡唑－４′－基）壬二酮－（１，９）（ＢＰＭＰＮＤ，Ｈ２Ａ）与三辛基氧膦（ＴＯＰＯ，Ｂ）的氯仿溶液，从硝酸介质中对Ｌａ（Ⅲ），Ｄｙ（Ⅲ）的协同萃取，计算了体系的酸性协萃系数ＲＡ和协萃系数Ｒ，用斜率法测得协萃合物的组成ＬａＡ．ＨＡ．Ｂ和ＤｙＡ．ＨＡ．Ｂ计算了协萃取平衡常数，研究了温度对协萃反应的影响，用萃取法制得了固态协萃合物，并对其组成，ＩＲ及ＴＧ     

某些有机硅及2—三丁基锡二茂铁衍生物的合成及表征

由Ｎ，Ｎ－二甲氨甲基二茂铁（Ｉ）单锂化后与三甲基氯硅烷（Ｍｅ３ＳｉＣｌ）反应，合成了２－（三甲硅基）二甲氨甲基二茂铁（Ⅱ）；Ⅱ再单锂化后与Ｍｅ３ＳｉＣｌ反应得到了２，５－二（三甲硅基）二甲氨甲基二茂铁（Ⅲ）；单锂化的Ｉ与Ｍｅ２ＳｉＣｌ２反是得到了双－（２－（二甲氨甲基）二茂铁基）二甲基硅烷（Ⅳ）双锂化Ｉ与二倍量的Ｍｅ３ＳｉＣｌ反应得到了２，１′－二（三甲硅基）二甲氨甲基二茂铁（Ｖ），由碘化（２－（     

2—氯／2—甲磺酰基—5—（2—苯基—4—喹啉基）—1,3,4—恶二唑…

借处理２－羟基－５－（２－苯基－４－喹啉基）－１，３，４－恶二唑同ＰＣｌ５／ＰＯＣｌ３之间的反应合成了２－氯－５－（２－苯基－４－喹啉基）－１，３，４－恶二唑（３）和通过２－Ｙｕ基－５－（２－苯基－４－喹啉基）－１，３，４－恶二唑的甲基化，然后氧化制得２－甲磺酰基－５－（２－苯基－４－喹啉基）－１，３，４－恶二唑（６）。并分别研究了３和６同胺、叠氮及肼的反应，得到２，５－二取代的恶二唑新衍生物。初     

2—乙基己基膦酸单（2—乙基己基）酯萃淋树脂分离—火花源质谱法测定…

本文采用萃取色谱法以２－乙基己基膦酸单（２－乙基己基）酯（Ｐ５０７）萃淋树脂为固定相，以ＨＣｌ－ＮＨ４Ｃｌ体系为淋洗液，研究了９９．９９９％￣９９．９９９９％的高纯Ｙｂ２Ｏ３中稀土杂质和Ｙｂ基体的分离条件，将杂质淋洗液富集于复合螯合剂－活性碳上，经灼烧灰化后制成样品电极，进行质谱测定。测定下限达０．０１￣０．０５μｇ／ｇ，可用于高纯Ｙｂ２Ｏ３中杂质的测定。回收率在８０％以上。     

4,4‘—双—（外型—二环[2,2,1]庚—2—烯—5,6—二酰亚胺）基二苯甲烷合成

４，４’－双－（外型－二环［２，２，１］庚－２－烯－５，６－二酰亚胺）基二苯甲烷合成沙耀武徐寿颐（清华大学化学系北京１０００８４）目前液晶显示器件（ＬＣＤ）已成为显示器件领域中的主流产品之一。液晶分子在玻璃基片表面的定向排列技术直接影响到液晶显示器件...     

1,2—双（1‘—苯基—3’—甲基—5‘—氧代吡唑—4’—基）—1,2…

用萃取法合成了１５种１，２－双（１＇－苯基－３＇－甲基－５＇－氧代吡唑－４＇－基）－１，２苯二酮（ＢＰＭＯＰＰ，简作Ｈ２Ｌ）稀土配合物。元素分析确定其化学组成为ＲＥ２Ｌ３·ｎＨ２Ｏ。通过电子光谱、红外光谱、核磁共振谱、热谱、摩尔电导等进行了表征，并讨论了配合物的性质。     

Vortex-Assisted Liquid–Liquid Microextraction (VALLME): Applications

Recently, a new and fast equilibrium-based solvent microextraction technique termed vortex-assisted liquid–liquid microextraction was developed. In this technique, the dispersion of the extraction solvent is enhanced by vortex mixing. The aim of the present review is to discuss the applications of vortex agitation in solvent-microextraction procedures.

     

Liquid crystalline derivatives of bis(tricarbollide)Fe(II)

A series of Schiff bases 2[n] with n = 4, 6, 8, 10, 12, and 18 was prepared by the condensation of 9,9'-diaminobis(tricarbollide)Fe(II) (1b) with appropriate 4-alkoxybenzaldehydes (3[n]). Thermal analysis showed that they form nematic and smectic phases with clearing temperatures above 200 degrees C. Comparative studies of series 2[n] and its organic analogs demonstrated that the effectiveness of bis(tricarbollide)Fe(II) in supporting liquid crystalline phases is between that of benzene and biphenyl for n < or = 18 and lower than that of benzene for n = infinity. The photophysical properties were investigated for the butoxy derivative 2[4] and modeled using ZINDO calculations.     

Liquid chromatography of josamycin on poly(styrene-divinylbenzene)

An isocratic liquid chromatographic method for the assay and purity control of josamycin using wide-pore poly(styrene-divinylbenzene) as the stationary phase is presented. Josamycin has been well separated from all the related leucomycins, present as impurities in commercial samples. Wide-pore PLRP-S 8 m 1000 Å has shown the best selectivity. The separation has been carried out at 65°C with a mobile phase of 2-methyl-2-propanol/0.2 mol/l potassium phosphate buffer pH 10.5/water (24.5: 5: 70.5, V/V) and a flow rate of 1.0 ml/min. UV detection has been performed at 232 nm. The total analysis time has been about 40 min. The method has been used to analyse commercial bulk samples and tablets containing josamycin base.Dedicated to Professor Dr. Dr. h.c. mult. J.F.K. Huber on the occasion of his 70th birthday     

Enhanced Fluorescence And Room Temperature Liquid Phosprorescence Detection In Pseudophase Liquid Chromatography (Plc)

Abstract

The effect of a micellar mobile phase on the fluorescence detection of a variety of polynucleararomatic hydrocarbons (PAH's) separated via HPLC is examined. It was found that the “fluorescence peaks” of the separated PAH's were enhanced up to ten times by the sodium dodecylsulfate micellar mobile phase. Furthermore, one can use room temperature liquid phosphorescence detection when the mobile phase consists of a deoxygenated aqueous solution of thallium and sodium dodecylsulfate micelles. The phosphorescence intensity was relatively weak and difficult to obtain compared to the fluorescence.     

Liquid Crystalline Dendritic Networks Derived from Poly(propylene imine) (PPI) Dendrimers

Summary: A nematic liquid crystalline network based on a poly(propylene imine) dendrimer [PPI‐(NH₂)₃₂ (G = 4)] was prepared in the form of films. In the network the PPI dendritic molecules are partially functionalised with a chiral aldehyde and are connected to each other by an achiral dialdehyde. The phase behaviour of the network was investigated by polarising‐light optical microscopy, differential scanning calorimetry, and X‐ray diffractometry. Thermoelastic measurements ruled out the possible elastomeric nature of the material.

Schematic of the nematic dendritic network prepared here.     

离子液体增塑的聚合物电解质

离子液体增塑的聚合物电解质;偏氟乙烯六氟丙烯共聚物;乙基甲基咪唑鎓四氟硼酸盐;微波合成;电学行为     

Liquid crystalline glycosteroids and acyl steroid glycosides (ASG)

ABSTRACT

As part of our studies on glycolipidic liquid crystals, we have investigated some molecules comprising a steroid moiety. These systems can exhibit several types of structures depending on their polarity pattern based on the number of polar and non-polar moieties and their resulting molecular shape. Therefore, to aid describing such systems, we have proposed a specific classification based on this polarity pattern. Many compounds in this family are natural products, which possess important biological properties. Some of the compounds have bolaphilic structures, with both a steroid and a fatty alkyl chain attached to the carbohydrate moiety, such as either the β-galactoside BbGL-1 or the α-glucoside α-CAG that are found in the membranes of the pathogens Borrelia burgdorferi and Helicobacter pylori, respectively. In this account, after a brief introduction on liquid crystalline glycolipids, we focus on carbohydrate–steroid hybrids, summarising our previous work on glycosteroids prepared by the CMGL-synthon strategy, and reporting our preliminary results on the thermotropic behaviour of acyl steroid glycosides (ASG), namely cholesteryl 6-O-acyl-β-gluco- and -galacto-pyranosides.     

聚[甲基丙烯酸（磺酸钠烷基酯）]高分子溶致液晶

溶致液晶是两亲分子有序组合体的一种形式.与表面活性剂相比,高分子溶致液晶的研究开展较少,其中以主链型溶致液晶为主,而侧挂型支链高分子溶致液晶报导极少[1-3],但含有离子的不同烷基侧链的高聚物在溶液中自织组成液晶的规律性和性质的研究,在基础理论和应用方面皆有重?..     

分子中部含齐聚氧化乙烯单元的酯-醚液晶

以4-(4′-烷氧基苯甲酰氧基)苯甲酸作为液晶中间体,合成了在分子中部含齐聚氧化乙烯的系列酯-醚液晶化合物.对其化学结构和液晶性能进行了表征,除个别化合物外,其余样品均具有热致液晶性.     

Optimal Parameters in High Speed Liquid Chromatography (HPLC)

After a decade, the first storm of development in high performance liquid chromatography seems to be abating. Providing the stationary phase and eluent are optimized, most routine analytical and semi-preparative separation problems require columns having between 1000 and 10000 theoretical plates. Commercial apparatus and columns completely satisfy these requirements. For many separation problems the efficiency of the columns on offer is greater than required. Since optimal (not maximal) separation is required with shorter analysis times, the column inlet pressure is increased in order to increase the eluent velocity, while at the same time reducing the column efficiency. The same result can be obtained by using shorter columns and lower pressures. Since inlet pressures of more than 100 bar are seldom required in routine analysis, the term “high pressure liquid chromatography” is a misnomer.—It is probable that difficult separation problems, where several 100 000 theoretical plates are required, will be studied in the next phase of development. It can be shown using nomograms that such problems can be solved within acceptable time limits using inlet pressures of less than 500 bar. Further possible directions of development are indicated.