碳热还原制备不同形貌的碳化硅纳米线

以酚醛树脂为碳源，正硅酸乙酯为硅源，硝酸镧和表面活性剂为调控剂，通过溶胶-凝胶和碳热还原反应制备了不同形貌的碳化硅纳米线。采用X射线衍射、扫描电子显微镜、透射电子显微镜和X射线散射能谱对所制备的碳化硅纳米线进行表征。结果表明，通过此方法所制备的碳化硅纳米线均为立方结构的β-SiC，分别具有直线状、竹节状和链珠状、分枝状等不同形貌。金属催化剂和表面活性剂对碳化硅纳米线的结构和形貌变化有重要影响。     

DNA光复活作用机理研究中的模型化合物

用模型化合物模拟光解酶诱导的DNA光复活作用，能深入认识其作用机理。介 绍了用于DNA光复活机理研究的各种模型化合物的合成，并综述了由模型化合物研 究得到的光复活机理，以及底物嘧啶二聚体的修复效率受外界因素的影响。     

有机锡试剂在有机合成中的某些新应用

本文阐述有机锡试剂在有机台成巾的一些新应用。在钯催化下,有机锡试剂与亲电试剂进行偶联,条件温和,收率高。有机锡试剂促进醇醛缩合,可用于不对称合成中。     

Ag-MoO3催化丙烯直接气相环氧化反应的原位红外研究

制备了对丙烯直接气相环氧化具有较好催化性能的Ag-MoO3催化剂, 采用原位FT-IR技术研究了丙烯、环氧丙烷及丙烯+氧气的混合气在Ag和Ag-MoO3催化剂表面上的吸附及反应行为. 研究表明, 丙烯在Ag和Ag-MoO3催化剂表面上吸附后, 均不发生化学反应, 而环氧丙烷吸附后在较高温度下则发生开环和聚合反应直至产生积炭. 与Ag催化剂相比, 在Ag-MoO3催化剂上, MoO3的加入在降低催化剂活性的同时, 在一定程度上抑制了产物环氧丙烷的开环及深度反应, 使环氧丙烷的选择性提高. 另外, 在较低的反应温度和较短的滞留时间下, 环氧丙烷发生深度反应的程度明显降低.     

具有双螺旋链的新型二维无机-有机骨架晶体材料Ni(PDC)(H2O)2的合成与结构

本文报道由H2PDC合成的新型维层状无机-有机骨架晶体Ni(PDC)(H2O)2(H2PDC=吡啶-2,5-二羧酸), 该化合物的一层是由右手螺旋Ni—O—C链与左手螺旋Ni-pdc链组成, 而邻近的一层则是由左手螺旋Ni—O—C链与右手螺旋Ni-pdc链组成, 层与层之间通过氢键作用形成了三维超分子结构. 用ICP、TG、IR和X射线单晶衍射分析等手段对其结构进行表征.     

恒电量瞬态扰动测量Tafel斜率及数据积分处理

提出了一个三参数积分法拟合恒电量强极化数据以测定Tafel斜率的新方法.实验证明,恒电量瞬态扰动测量碳钢在酸溶液中的腐蚀,获得的Tafel斜率与消除了溶液电阻影响的Tafel外推结果有很好的一致性,说明恒电量法有效地消除了溶液电阻对该体系测量结果的影响,并且通过电化学和失重实验验证表明,这种快速测量可以获得准确的腐蚀速率.这种新的恒电量强极化积分算法相对微分法的优势体现在算法简捷和用于数值计算的数据具有较高的信噪比,因此能够提高测量精度.     

芳香环状低聚物组分分布与单体结构关系的研究

根据Jacoson-Stockmayer(J-S)环化理论,应用基质辅助激光解吸离子化飞行时间质谱(MAIDL-TOFMS),对一系列芳香环状低聚物组分分布进行分析,研究了芳香环状低聚物的组分分布与单体结构的关系,结果表明,在芳香聚酯、聚膦酸酯及芳香聚醚环状低聚物系列中,Incn与Inn呈良好的线性关系,符合J-S理论分布,在环状聚酯及聚膦酸酯系列中,低聚物的组分分布受双酚单体的中心键角影响,单体的中心键角在100°～120°之间,其中心键角愈小,γ值愈大,而在聚醚系列中,在固定一种单体的前提下,环化物的组分分布受另一单体键角的影响与环状聚酯和聚膦酸酯相一致.     

Baylis-Hillman Reactions of Sulfonyl Aldimines or Aryl Aldehydes with 3-Methylpenta-3,4-dien-2-one or 3-Benzylpenta-3,4-dien-2-one

The attempted Baylis-Hillman reactions of sulfonyl aldimines or aryl aldehydes with 3-methylpenta-3,4-dien-2-one or 3-benzylpenta-3,4-dien-2-one gave the corresponding Baylis-Hillman adducts in moderate yields in DMSO under the catalysis of DBU or PMe3, respectively. Moderate diastereoselectivities were observed in the reaction of 3-benzylpenta-3,4-dien-2-one with N-arylmethylidene-1-naphthalenesulfonamides catalyzed by chiral catalyst cinchona alkaloid derivative TQO {4-（3-ethyl-4-oxa-1-azatricyclo[4.4.0.0^3,8]dec-5-yl）quinolin-6-ol}.     

Solid Phase Catalytic Oxidation of Alcohols by Polymer Supported Rare Earth Catalysts

Oxidation of alcohols to the corresponding aldehydes or ketones is one of the most fundamental reactions in organic chemistry [1,2]. Some of the products of the oxidation exhibit an important role in the organic synthesis as well as pharmaceutical synthesis. In most reactions, the lanthanide complexes show satisfied catalytic activities for some compounds. Furthermore, there has been increasing interest in the lanthanide complexes and several reports have appeared in the literature [3, 4]. But the exploitation of these complexes for the oxidation of some organic substrates has been limited. Here we reported a method for the preparation and the catalytic properties as well as the recycling of lanthanide complexes in oxidation of alcohols.The synthetic procedure for the polymer supported lanthanide complexes is shown as following(scheme 1):●-NH2+CICH2COOH(C2Hs)3N→●-NHCH2COOHM=Ce(Ⅲ), Tb(Ⅲ), Sm(Ⅲ)scheme 1The oxidation of benzyl alcohol was carried out in the presence of iodosylbenzene by the polymer supported Ce(Ⅲ), Tb(Ⅲ) and Sm(Ⅲ) catalysts at 80℃ for 4.0h, the yields of benz-aldehyde are as following (table 1):Table 1 Oxidation of benzyl alcohol with the supported catalysts**Reaction condition: benzyl alcohol 0.1 mmol, iodosylbenzene 0.15mmol,catalyst 0.2mg, 80℃ for 4.0h in 1,2-dichloroethane.It can be seen from the table that the Tb(Ⅲ) complex shows higher catalytic activity for the oxidation of benzyl alcohol. Further investigation is now being carded on to optimize the results.     

Synthesis and Properties of Polyetherketones Containing Sulfide and Phthalazinone

High molecular weight copoly(ether ketone)s (PEK) based on 4-(4-hydroxyphenyl)-1-phthalazinone (DHPZ)/4,4′-thiobisphenol (TBP)/4,4′-diflourodiphenylketone (DFK) were prepared by nucleophilic substitution polycondensation. The copolymers were characterized by FT- and ^1H-NMR. Thermal properties and solubility of copolymers were studied.