Iron‐Catalyzed Azidoalkylthiation of Alkenes with Trimethylsilyl Azide and 1‐(Alkylthio)pyrrolidine‐2,5‐diones

A simple, efficient and practical iron‐catalyzed azidoarylthiation of alkenes has been developed at room temperature, and the corresponding products containing ortho‐sited sulfide and azide units were obtained in moderate to good yields with good tolerance of functional groups. The protocol uses readily available 1‐(alkylthio)pyrrolidine‐2,5‐diones and trimethylsilyl azide as the alkylthiation and azidation reagents, respectively, inexpensive and environmentally friendly iron chloride as the catalyst without addition of any ligand and additive.

     

Chemical Synthesis of a Synthetic Analogue of the Sialic Acid‐Binding Lectin Siglec‐7

As a basis for the development of an artificial carbohydrate‐binding lectin, we chemically synthesized a domain of siglec‐7, a well‐characterized sialic‐acid‐binding lectin. The full polypeptide (127 amino acids) was constructed by sequential native chemical ligation (NCL) of five peptide segments. Because of poor cysteine availability for NCL, cysteine residues were introduced at suitable ligation sites; these cysteine residues were alkylated in order to mimic native glutamine or asparagine residues, or converted to an alanine residue by desulfurization after NCL. After folding the full‐length polypeptide, the sialic‐acid‐binding activity of the synthetic siglec‐7 was clearly demonstrated by STD NMR and ELISA experiments. We succeeded in the synthesis of siglec‐7 by installing three extra cysteine residues with side‐chain modifications and found that these modifications did not affect the binding activity.     

Evaluation of the Interaction between Phosphohistidine Analogues and Phosphotyrosine Binding Domains

We have investigated the interaction of peptides containing phosphohistidine analogues and their homologues with the prototypical phosphotyrosine binding SH2 domain from the eukaryotic cell signalling protein Grb2 by using a combination of isothermal titration calorimetry and a fluorescence anisotropy competition assay. These investigations demonstrated that the triazole class of phosphohistidine analogues are capable of binding too, suggesting that phosphohistidine could potentially be detected by this class of proteins in vivo.     

季戊四醇改性三氯化铝催化C_(12)～C_(14)烯烃齐聚反应的研究

使用季戊四醇改性三氯化铝催化剂,对C12-C14的内烯烃的齐聚反应进行研究,对反应过程中的三氯化铝用量,改性剂用量,反应时间,反应温度对齐聚物的收率的影响。确定其最佳的工艺条件,三氯化铝用量2%,改性剂季戊四醇用量0.25%,水浴反应加热温℃度,反应时间4 h,在此条件下,以C12-C14内烯烃为反应主原料合成了聚烯烃合成油,对其物理性质和化学性质进行研究。研究结果显示,采用此质量分数的C12-C14的内烯烃,可以合成100℃黏度为7.15 mm2·s-1。粘度指数为133和凝点-39℃的聚烯烃合成油,其收率为78%,具有黏度低,凝点低和黏度指数高的特点,是高质量的润滑油基础油。。     

环氧大豆油丙烯酸酯光固化保护材料的合成

以环氧大豆油和丙烯酸为原料合成环氧大豆油丙烯酸酯(ESOA),对催化剂种类和反应温度进行探讨。以四丁基溴化铵为催化剂、100℃时合成的ESOA预聚体为主体树脂、三羟甲基丙烷三丙烯酸酯(TMPTA)为活性稀释剂、184为光引发剂进行涂膜紫外光固化。结果表明,制得的紫外光固化保护膜材料附着力为1级,硬度为5H,收缩率小且具有良好的柔韧性及耐磨性。     

金刚石——前生·今世·未来（一）

20世纪50年代人工合成金刚石成功之后,金刚石家族就出现了天然金刚石和人造金刚石两大分支。文章全面系统综合地介绍了它们的发展历程和未来。     

国际人造金刚石行业近期发展态势（上）

人造金刚石的应用从最初的工业应用领域发展到宝石级人造金刚石用于珠宝行业然后又发展到纪念品钻石服务于丧事家庭和特殊礼品等。文章阐述了工业用人造金刚石、宝石级人造金刚石与纪念品钻石的最新进展以及工业用人造金刚石在高科技与各工业部门的最新应用。全面反映国际工业用人造金刚石、宝石级人造金刚石和纪念品钻石技术的当前发展水平以及人造金刚石的未来发展趋势。此外,对国际上主要的工业用人造金刚石生产企业以及宝石级人造金刚石与纪念品钻石生产厂家的发展作简单介绍。     

基于遥感解译与模糊数学的矿山地质环境综合评价——以戈壁荒漠区某有色金属矿山为例

戈壁荒漠区属生态环境脆弱区,原生地质环境敏感性强,矿业开发一定程度上加剧了土地沙化、盐渍化和荒漠区砾幕层的破坏,但戈壁荒漠区以往矿山地质环境调查工作程度较低,亦亟需开展矿山地质环境调查与评价工作。通过基于遥感解译的地质环境调查,查明了矿山地质环境现状。建立了适用于戈壁荒漠区矿山地质环境评价指标体系,通过模糊数学综合评价与综合指数模型评价,得到模糊综合评判指数与综合评价指数分别为4.806、4.833,确定矿山地质环境影响程度为中度影响。基于遥感解译与模糊数学的评价方法在戈壁荒漠区有色金属矿山地质环境综合评价中有效可行,为有色金属矿山地质环境调查与评价提供了方法借鉴,为矿山地质环境保护与恢复治理及土地复垦提供了依据。     

Bioaugmentation of floating treatment wetlands for the remediation of textile effluent

This pilot study evaluated the effects of bacterial augmentation on the efficiency of floating treatment wetlands (FTWs) to remediate textile wastewater. Two wetland plants, Phragmites australis and Typha domingensis, were used to develop FTWs, which were then augmented with a bacterial consortium of three strains (Acinetobacter junii, Pseudomonas indoloxydans, and Rhodococcus sp.). Results showed that both plant species removed colour, organic matter, toxicity, and heavy metals from textile wastewater and their removal efficiency was further enhanced by augmentation with bacteria. The maximum removal efficiencies of colour, COD and BOD after an 8‐day period were 97, 87 and 92%, respectively, by FTWs carrying P. australis inoculated with the bacterial consortium. Furthermore, the same combination showed 87–99% reduction of heavy metals in the textile wastewater as well. These results indicate that FTWs can be used for the treatment of textile effluent and their working efficiency can be improved by plant‐bacterial synergism.     

稀土催化剂在MDI型聚氨酯塑胶跑道材料中的应用研究

研究了MDI型聚氨酯塑胶跑道材料中稀土催化剂的固化性能及其对样品物理性能的影响。结果表明:稀土复合催化剂可以完全取代常用的有机Pb/Hg、Pb/Zn和Zn/Sn等复合催化剂体系,从而消除MDI型聚氨酯塑胶跑道材料的生产和使用过程中Pb、Hg污染。