酚羟基桥八胺穴醚及其镧系配合物的合成与表征(英)

通过将相应的席夫碱穴醚还原的方法合成了三个具有不同取代基（R=溴，4；苯基，5；甲基，6）的新的酚羟基桥的八胺穴醚，并对其进行了表征。将这些新穴醚与镧系元素的高氯酸盐反应制备了它们的镧系元素配合物(7～12)。核磁、质谱、红外、紫外和元素分析等表征结果表明这些镧系元素配合物为单核配合物并可能具有N₃O₃N₃型的对称配位结构。讨论了铕(Ⅲ)配合物8在乙腈溶液中的荧光性质。     

铜锌超氧化物歧化酶(Cu2Zn2SOD)在汞电极上的吸附研究

金属氧化还原蛋白质的电化学行为作为生物电化学领域中一个重要的研究内容,受到了广泛的关注犤1～3犦,生物体系一些重要的反应均与基本电荷运动有关,如生物催化、神经传导、光合作用以及呼吸作用等均涉及到一些重要氧化还原蛋白质的氧化还原过程。利用电化学的基本原理和实验方法,不但能在生命体系和有机组织的整体水平上,更主要是能在分子和细胞水平上研究氧化还原蛋白质体系中的电子转移以及氧化态转化的化学本质和规律。铜锌超氧化物歧化酶(Cu2Zn2SOD)是一个二聚体,由两个等同的亚单位组成,每一个亚单位含有咪唑桥联的铜?和锌?离子,催…     

Synthesis,spectroscopy and crystal structure of a new heterodinuclear silver(I)—copper(I) cryptate

A new heterodinuclear cryptate [AgCuL](ClO₄ ^–)₂ was synthesized by transmetallation via its precursor [Ag₂L](ClO₄ ^–)₂ (L = ligand). The electrospray mass spectrum (ES-MS) showed that the heterodinuclear entity exists in the solution. The X-Ray structure analysis shows that the Ag^I ion has tetrahedral geometry while Cu^I lies in a three-coordinate environment.     

CuOx/TiO2光催化水蒸气还原CO2反应研究

以商品TiO2-P25为原料,通过浸渍法负载一定量过渡金属Cu,得到一系列不同含量的CuOx/TiO2光催化剂.利用X射线衍射(XRD),X-射线光电子能谱(XPS),BET,高分辨率透射镜(HRTEM),X射线荧光光谱(XRF)和光致发光光谱(PL)等方法对催化剂进行了详细表征,在自建的光催化反应器中评价了气态水光催化还原CO2反应的活性和CH4收率.结果表明负载CuOx后的TiO2纳米材料光催化性能显著提高,其中1%CuOx/TiO2样品紫外光照72 h后,CH4生成量达到了24.86μmol.gTi-1.同时,CuOx负载量、反应温度、反应时间等因素对CH4收率均有显著影响.     

用MnO_2离子筛吸附剂从溶液中提取锂(英文)

研究了MnO2离子筛的制备、表征及其提锂性能。通过控制低温水热合成反应条件制备了4种不同晶相的一维纳米MnO2,进一步用浸渍法制备了Li-Mn-O三元氧化物前驱体,并经酸处理后得到对Li+具有特殊选择性的离子筛。用XRD、吸附等温线、吸附动力学及pH滴定等手段对产物的晶相结构和Li+吸附性能进行了研究。结果表明,SMO-b和SMO-d离子筛的Li+平衡吸附量符合Freundlich吸附等温方程。反应物浓度对MnO2不同晶面的生长速率有不同的影响,但(NH4)2SO4对吸附容量并无提高。吸附速率方程符合一级动力学Lagergren方程。MnO2离子筛Li+的吸附量远远高于Na+。     

Three-step calcination synthesis of high-purity Li8ZrO6 with CO2 absorption properties

Li(8)ZrO(6) contains a high lithium content and may bear a great ability of CO(2) absorption, yet the reports about the properties of CO(2) absorption on Li(8)ZrO(6) are few to date for its difficulty in production. In this paper, high-purity Li(8)ZrO(6) is synthesized via a three-step calcination method combined with an effective lithium source and a suitable initial Li/Zr molar ratio. The produced Li(8)ZrO(6) possesses a great CO(2) absorption capacity of about 53.98 wt % at 998 K, which could be well-maintained in a wide range of CO(2) partial pressures of 0.1-1.0 bar although it decreased gradually during the multicycle process of CO(2) absorption-desorption in a 10% CO(2) feed stream because of the high working temperature. These properties imply that Li(8)ZrO(6) may be a new option for high-temperature CO(2) capture applied in industrial processes such as a steam methane reformer.     

CTAB对H2O2氧化抗坏血酸反应动力学的影响

H₂O₂氧化抗坏血酸H₂A的反应为一复杂过程,其过程可用下面可逆连续反应来描述:HA－＋H₂O₂ A,本文用热导式热量计研究了该复杂反应在25 ℃和pH=7的磷酸缓冲溶液(离子强度μ=0.1 mol•L^－1)以及在阳离子表面活性剂十六烷基三甲基溴化铵(CTAB)存在下的反应动力学, 获得了不同CTAB浓度下该复杂反应的表观动力学参数k₁、k₂和k_－1.研究结果表明,表面活性剂CTAB单体分子对反应参数k_－1影响不大, 但却能催化第一步正向反应使k₁变大,而使k₂减小; 在临界胶束浓度cmc附近k₁达到最大值,随后又降低；低浓度胶束对k_-1影响不大,而使k₂增大；高浓度胶束则使k_-1增大而使k₂减小. 低浓度CTAB胶束对的活性影响不大, 而高浓度CTAB胶束将较显著地促进的歧化过程, 减缓的氧化过程. 胶束的静电效应、疏水效应和局部浓聚效应是影响上述反应的重要因素.     

牛红细胞铜锌超氧化物歧化酶（BESOD）在汞电极表面吸附行为的研究

牛红细胞铜锌超氧化物歧化酶（ＢＥＳＯＤ）在汞电极表面吸附行为的研究钱雯，孟庆国，罗勤慧，沈孟长（南京大学配位化学研究所，配位化学国家重点实验室南京，２１００９３）关键词铜锌超氧化物歧化酶，吸附，循环伏安，双阶跃计时电量超氧化物歧化酶是超氧离子（·Ｏ）...     

A label-free electrochemical immunosensor based on gold nanoparticles for detection of paraoxon

An electrochemical immunosensor for the direct determination of paraoxon has been developed based on the biocomposites of gold nanoparticles loaded with paraoxon antibodies. The biocomposites are immobilized on the glassy carbon electrode (GCE) using Nafion membrane. On the immunosensor prepared paraoxon shows well-shaped CV with reduction and oxidation peaks located −0.08 and −0.03 mV versus SCE, respectively. The detection of paraoxon performed at −0.03 mV is beneficial for guaranteeing sufficient selectivity. The amount of the biocomposite consisting gold nanoparticles loaded with antibodies and the volume of Nafion solution used for fabricating the immunosensor have been studied to ensure sensitivity and conductivity of the immunosensor. The immunosensor has been employed for monitoring the concentrations of paraoxon in aqueous samples up to 1920 μg l⁻¹ with a detection limit of 12 μg l⁻¹.