Effect of Pb2＋ on the Kinetic and Spectral Characterization of Ribulose-1,5-bisphosphate Carboxylase/Oxygenase

本文利用各种光谱手段在体外研究了各种浓度的Pb2+对菠菜Rubisco活性影响的机制。 结果表明,Rubisco活性随着Pb2+处理浓度的增加而逐渐下降,低浓度Pb2+下Rubisco的动力学常数和最大反应速率分别为1.74 µM 和 0.42 µmol CO2/mg protein∙min,高浓度Pb2+下Rubisco的动力学常数和最大反应速率分别为11.82 µM and 0.28 µmol CO2/mg protein∙min。光谱学分析证实Pb2+可直接结合到Rubisco上, 其结合位点数为1.1个,结合常数分别为8.63×104 和 2.18×105 L/mol。ICP-MS和圆二色谱分析证实Pb2+取代了酶活性中心的Mg2+ 并改变了酶的构象。     

Hydrothermal Synthesis and Crystal Structure of a New One-dimensional Cobalt(Ⅱ) Complex with 2-Pyridinecarboxyic Acid and 4,4'-Bipyridine Ligands

A new metal-organic coordination polymer [Co(2-pya)2(4,4'-bipy)]2n·[(4,4'- bipy)0.5· H2O]2n(2-pya = 2-pyridinecarboxylic acid, 4,4'-bipy = 4,4'-bipyridine) 1 has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, TG and single-crystal X-ray diffraction. The complex crystallizes in tetragonal, space group I41/a with a = b = 22.719(2), c = 10.710(2) A, V = 5527.8(14) A3, C54H46N10Co2O10, Mr = 1112.87, Dc = 1.337 g/cm3,μ(MoKα) = 0.665 mm-1, F(000) = 2296, Z = 4, the final R = 0.0633 and wR = 0.1096 for 1261 observed reflections (I ＞ 2σ(I)). It exhibits a one-dimensional chain-like structure constructed by mixed ligands of 2-pyridinedicarboxylic acid and 4,4'-bipyridine.     

AM1法研究乙烯与环己－1，3－二烯热加成反应

用ＡＭ１方法（采用非限制的Ｈａｒｔｒｅｅ－ＦｏｃｋＵＨＦ计算）研究乙烯与环己－１，３－二烯的热Ｄｉｅｌｓ－Ａｌｄｅｒ反应。结果表明反应是放热的且存在两条竞争的路径；协同反应的活化能以及双自由反应速度控制步骤的活化能分别为１１２．６６７ｋＪ／ｍｏｌ和７８．４０６ｋＪ／ｍｏｌ。     

微波诱导低级醇的等离子体化学反应

微波诱导低级醇的等离子体化学反应王真，洪品杰，张承聪，戴树珊（云南大学化学系，昆明，６５００９１）关键词微波，等离子体化学，低级醇等离子体能产生大量的活性自由基、亚稳态粒子和激发态离子，它所包含的能量传递过程和反应过程不仅与反应碰撞理论有关，而且还涉...     

过渡金属与邻香兰素氨基酸类Schiff碱配合物合成及其性质的研究

本文合成了邻香兰素白氨酸合Cu(Ⅱ) 1, Ni(Ⅱ) 2, 邻香兰素苯丙氨酸合Ni(Ⅱ) 3及邻香兰素丙氨酸合Zn(Ⅱ) 4四种配合物。对其组成、结构进行了分析表征, 研究了它们的热稳定性及非等温热分解动力学, 用微分和积分法进行分析, 推断了第一步热分解反应机理, 得到了热分解反应动力学方程此外, 还得到了配合物的热分解反应动力学补偿效应数学表达式。     

载体化Et(Ind)2ZrCl2催化乙烯-苯乙烯共聚

用均相亚乙基二(1-茚基)二氯化锆(Et(Ind)₂ZrCl₂)催化乙烯和苯乙烯共聚时,所得共聚物中苯乙烯链节含量和聚合活性不能同时满足聚乙烯功能化的要求^[1,2].因此我们用SiO₂对Et(Ind)₂ZrCl₂进行载体化.     

RECTIFYING EFFECT OF POLYANILINE(PANI)/N-TYPE POROUS SILICONE HETEROJUNCTION*

Heterojunctions between polyaniline (PANI) and n-type porous silicon (PS), Al/PS-PANI/Au cell,were fabricated, and the rectifying parameters of this heterojunction diode were measured as a function of thepreparation conditions of PANI and PS, the electronic structure of PANI as well as cell structure. Therectifying parameters of Al/PS-PANI/Au cell were determined to be γ= 1 .8×10~1～ 1 .0×10~5 for the rectifyingratio at 3V, n = 3 ～12 for the ideal factor,j_0 = 8.0×10~(-5)～5.6×10~(-2) mA/cm~2 for the reversed saturated currentdensity, and φ_b = 0.67～ 0.83 V for the barrier height, respectively. The best rectifying heterojunction diodemade between PANI and n-type PS with higher rectifying factor (γ= 1 .0×10~5 at 3V ), output current (>1500mA/cm~2 at 3V) and lower ideal factor (n = 3.3) was obtained by preventing the oxidation of PS beforeevaporating Al electrode.     

The Luminescence of The Phosphor Sr_2ZrO_4 with One-dimensional Chains Structure

IntroductionThenumberofzirconateswhichcanbeexcitedbyconventionalUVexcitation(X>240urn)issmall,sothatzirconateemissioniseasilyoverlooked.SomecompoundswhichabsorbcoventionalUVradiation.ig.ZrO,andBaZrO,(240urn)donotluminenceowingtoenergymigration=.Ontheotherhand,althoughseveralzircinatessuchasZrP,O,:.BaZrSi,O,'andSrZrSi=O,'showefficientUVzirconateemission(around300"m),theirexcitationwavelengthsareshorterthanusual(200"m).Moreover.theirluminescenceareatverylowtemperature(4.2K),whichlimits…     

基于半刚性配体的柔性超微孔金属有机骨架的合成及其尺度选择性二氧化碳捕获

基于半刚性的配体3′,5′-di(1H-1,2,4-triazol-1-yl)-(1,1′-biphenyl)-3,5-dicarboxylic acid (H₂DTBDA)和硝酸钴制备了一个柔性超微孔的金属有机骨架{[Co(DTBDA)]·4H₂O}_n (FJI-H35),并对该材料的结构进行了系统的表征。FJI-H35活化以后可以发生自适应的结构转变,使得孔径从0.43 nm收缩到0.37 nm。气体吸附测试表明FJI-H35可以从氮气和甲烷中选择性捕获二氧化碳,具有很高的吸附选择性和相对低的吸附焓。突破实验进一步证实FJI-H35可以从二氧化碳/氮气(15∶85,V/V)和二氧化碳/甲烷(50∶50,V/V)混合气中高效选择性捕获二氧化碳。     

1,2-二乙炔基四苯基乙硅烷与1,2-二乙炔基四甲基乙硅烷的共聚及其光解

1,2-二乙炔基四苯基乙硅烷与1,2-二乙炔基四甲基乙硅烷在催化剂铑(Ⅰ)络合物[氯化三-(三苯基膦)铑]的作用下得到一种新的含硅共聚物。实验证明此共聚物的主链是有规交替结构。研究了固体薄膜及其溶液的光解作用,并测定了SbF_5蒸气处理后的共聚物薄膜的导电性。