高分子固载化Lewis酸催化剂——聚苯乙烯-三氯化铝/四氯化钛复合物

<正> 均相催化剂的固载化是目前催化剂研究方向之一。Skct等首次将BF_5和AlCl_3分别与苯乙烯反应制成高分子催化剂,对酯化、缩醛、缩酮等有机反应具有良好的催化作用。我们曾将四氯化钛与聚苯乙烯反应制成一种稳定复合物,有良好的催化效能。为了改进其重复使用性能,本文将等摩尔的AlCl_3,和TiCl_4的Lewis酸同时与聚苯乙烯交     

正丁基黄原酸根合镉(Ⅱ)的合成和晶体结构

黄原酸配合物以及它们与各种路易斯碱反应的产物得到广泛的研究犤１～４犦。可溶性的黄原酸碱金属盐广泛用于汞、银、镉等金属的萃取分离犤５～７犦，并且这类盐对于汞中毒具有解毒作用犤８犦。E．D．Zelmon等犤９犦对过渡金属黄原酸配合物的非线性光学性质进行了研究。但迄今为止，对黄原酸镉配合物与路易斯碱的反应与结构研究较少。我们首先合成了一种配位聚合物犤Cd（S２CO－n－C４H９）２犦n晶体，然后利用吡啶与犤Cd（S２CO－n－C４H９）２犦n反应破坏其原有配位聚合物的结构，得到了犤Cd（C５H５N）２（S２CO－n－C４H９）…     

氰基乙烯基苯胺衍生物的电化学行为

本文利用循环伏安法研究了电子给-受体模型化合物——氰基乙烯基苯胺衍生物的电化学行为,并对推电子取代基团—NH_2和—N(CH_3)_2与吸电子取代基团氰基乙烯基对化合物电化学行为的影响进行了较为详细的讨论.提出了这些化合物的电氧化态和电还原态的结构,通过分析比较叔、仲和伯自由基对化合物电化学行为的影响,探讨了电极反应机理.     

Synthesis and Crystal Structure of N-cyclopropyl-9 -（3,4-dicholophenyl）- 1,2,3,4,5,6,7,8,9,10-decahydroacridine -1,8-dione under Microwave Irradiation

1 INTRODUCTION aryl or methyl group to the nitrogen atom of these compounds leads to enhanced activities of fluo- A lot of natural and synthetic compounds con- rescence[7, . Since the pyridine scaffold is included 8] taining acridine skeletons display interesting biolo- in decahydroacridine-1,8-dione, a question is whether gical and physical activities[1]. Acridinedione, for the same modification on the nitrogen atom of de- example, has been identified as antimalarial and cahydroacridine-1…     

IONIC CONDUCTIVITY OF METHYLSILOXANE TERMINATED POLYETHYLENE OXIDE WITH LITHIUM PERCHLORATE NETWORK FILMS

Complex films of crosslinked poly(methylsiloxane-co-ethylene oxide) and lithium perchlorate were prepared. These solid state polymeric electrolytes show a markedly higher ionic conductivity, and excellent flexibility. The ionic conductivity of the network films closed to 10~(-5) Scm~(-1) at room temperature. The effects of Li~+ content, species and contents of crosslinking agents, molecular weight of poly(ethylene oxide) and temperature on the ionic conductivity of the network films were also investigated.     

氧化酶及烷烃氧化

记述了氧化酶在生物催化中的应用. 较之传统的化学反应, 氧化还原生物催化反应有较好的选择性、可控性和经济性, 人们正在积极地寻找这类催化剂. 自然界中被高度还原的烃类品种丰富, 因此催化烷烃末端或近末端氧合反应的酶也相对容易找到. 很多这一类的酶生化特性已作了详细的描述, 烷烃加氧酶催化高附加值反应的潜力已得到了广泛地认可.     

Small Peptides Catalyzed Direct Aldol Reactions of Aldehydes with Hydroxyacetone with Regiocontrol in Aqueous Media

Very recently, we[1] found that L-proline amides and dipeptides acted as efficient catalysts for the asymmetric direct aldol reaction. We report here that L-proline-based peptides 1～5 can catalyze the aldol reactions of hydroxyacetone with aldehydes 6 in aqueous media, to give 1,4-diols (7), the disfavored products with either aldolase or L-proline. Both peptides 3 and 4 give good results.     

硝酸铽与1，1，1′，1′-四(吡啶-2-羧酸酯基)联三甲基丙烷配合物的合成、表征及荧光性质

Solid complex of terbium nitrate with a novel tetrapodal ligand, 1,1,1′,1′-tetra(2-pyridinecarboxylester)-di(trimethylpropane) was prepared. This new complex with the formula of [TbL(NO₃)](NO₃)₂·2H₂O was charact-erized by elemental analysis, molar conductivity, IR spectroscopy and thermal analysis. At the same time, the luminescent property of the complex was also studied.     

流动注射壳聚糖在线微柱预富集电热原子吸收光谱法测定痕量Cr(Ⅵ)

以天然高分子材料壳聚糖作在线预富集柱填料,流动注射与电热原子光谱联用测定痕量Cr(Ⅵ).采样体积5.80mL,采样频率22样/h,富集倍数51倍,线性范围0.02μg/L～0.12μg/L,该方法的检出限(3s,n=11)0.69ng/L,相对标准偏差5.1%(CCr(Ⅵ)=0.10μg/L,n=11).将该方法用于环境水样、茶叶样品和头发样品中Cr(Ⅵ)的测定,结果满意.     

Preparation of a Star Network PEG-based Gel Polymer Electrolyte and Its Application to Electrochromic Devices

A star network polymer with a pentaerythritol core linking four PEG-block polymeric arms was synthesized, and its corresponding gel polymer electrolyte based on lithium perchlorate and plasticizers EC/PC with the character being colorless and highly transparent has been also prepared. The polymer host was characterized and confirmed to be of a star network and an amorphous structure by FTIR, ^1H NMR and XRD studies. The polymer host hold good mechanical properties for pentaerythritol cross-linking. Maximum ionic conductivity of the prepared polymer electrolyte has reached 8.83 × 10 ^-4 S·cm^-1 at room temperature. Thermogravimetry （TG） of the polymer electrolyte showed that the thermal stability was up to at least 150 ℃. The gel polymer electrolyte was further evaluated in electrochromic devices fabricated by transparent PET-ITO and electrochromically active viologen derivative films, and its excellent performance promised the usage of the gel polymer electrolyte as ionic conductor material in electrochrornic devices.