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41.
This paper describes a microfluidics-based sensing system that relies on electrochemical detection and electrogenerated chemiluminescent (ECL) reporting. The important result is that the ECL reporting reaction is chemically decoupled from the electrochemical sensing reaction. That is, the electrochemical sensing reaction does not participate directly in the ECL process, but because electrochemical cells require charge balance, the sensing and ECL reactions are electrically coupled. This provides a convenient and sensitive means for direct photonic readout of electrochemical reactions that do not directly participate in an ECL reaction and thus broadens the spectrum of redox compounds that can be detected by ECL. The approach can be implemented in either a two-electrode or bipolar (single-electrode) configuration. By manipulating the placement and dimensions of the conductors, the photonic response can be enhanced. The system is used to electrochemically detect benzyl viologen present in solution and report its presence via Ru(bpy)(3)(2+) (bpy = 2,2'-bipyridine) luminescence.  相似文献   
42.
过渡金属酞等配合物(MPC)用手均相液相氧化中作催化剂已有不少报导,象许多均相催化剂一样,MPC用于均相反应存在着难于从反应体系中分离出来的问题.把均相配合物催化剂固载在无机氧化物如硅股或有机高分子载体上是解决这一问题的一种方法.我们曾尝试把MP。固载在分子筛载体和硅胶载体上,并用ESR研究其对O2的活化作用[1,2].本文报导MPc通过共价键键联固载在SiO2上,并研究其对O2的活化作用.1实验部分1.1试剂HSIC13为日本东京化成株式会社产品,二级试剂·发烟硫酸(SO。质量分数大于20%)为分析纯试剂.PCl5为化学纯试…  相似文献   
43.
Metalation of covalent organic frameworks (COFs) is a critical strategy to functionalize COFs for advanced applications yet largely relies on the pre-installed specific metal docking sites in the network, such as porphyrin, salen, 2,2′-bipyridine, etc. We show in this study that the imine linkage of simple imine-based COFs, one of the most popular COFs, readily chelate transition metal (Ir in this work) via cyclometalation, which has not been explored before. The iridacycle decorated COF exhibited more than 10-fold efficiency enhancement in (photo)catalytic hydrogen evolution from aqueous formate solution than its molecular counterpart under mild conditions. This work will inspire more functional cyclometallated COFs to be explored beyond catalysis considering the large imine COF library and the rich metallacycle chemistry.

This study describes cyclometallation as a new metal binding mode for imine-based COFs. The iridacycle decorated COF could be used for catalytic hydrogen evolution from aqueous formate solution with high stability and high efficacy.  相似文献   
44.
Yang W  Lu C  Zhang Q  Chen S  Zhan X  Liu J 《Inorganic chemistry》2003,42(22):7309-7314
The hydrothermal reaction of NaVO(3).H(2)O, barbituric acid, NH(2)NH(2).2HCl, H(3)PO(4), and H(2)O gave a novel heteropolyoxovanadate Na(6)[(P(V)O(4))V(V)(6)V(IV)(12)O(39)](2).H(3)PO(4).31H(2)O (1) and an unexpected phase Na(2)[C(12)H(6)N(6)O(9)].7H(2)O (2). The basic building blocks in 1 are the six-capped sphere-shaped heteropoly anion [(P(V)O(4))V(V)(6)V(IV)(12)O(39)](3-) with framework similar to that of the reported polyoxovanadates possessing [V(18)O(42)] clusters encapsulating VO(4) or other ions. These heterpoly anionic units are linked via V[bond]O[bond]V bridges into an interesting 3D straight-channel structure. The structure of 2 consists of novel organic anions ([C(12)H(6)N(6)O(9)](2-), 5,5-bis(2',4',6'-trioxopyrimidyl)barbital, representing the first oxidized barbituric acid trimer) linked via sodium ions into 1D hollow tubes with diameter of 4.49 x 6.86 A and further connected into a three-dimensional framework via hydrogen bonds.  相似文献   
45.
Direct optical detection of singlet oxygen from a single cell   总被引:1,自引:0,他引:1  
Singlet oxygen has been detected in single nerve cells by its weak 1270 nm phosphorescence (a1deltag --> X3sigmag-) upon irradiation of a photosensitizer incorporated in the cell. Thus, one can now consider the application of direct optical imaging techniques to mechanistic studies of singlet oxygen at the single-cell level.  相似文献   
46.
Based on carbon nanofibers (CNFs) as a solid phase extraction adsorbent, a microcolumn preconcentration method coupled to inductively coupled plasma mass spectrometry (ICP–MS) was developed for the determination of trace elements (Mn, Co and Ni). The effect of various experimental parameters such as pH, sample flow rate and volume, elution solution and interfering ions on the retention of the studied ions have been investigated systematically. During all the steps of the experimental process, Mn, Co and Ni could be quantitatively sorbed on the microcolumn containing CNFs in the range of pH 6.0–9.0, and then eluted completely with 0.5 mol ml− 1 HNO3. A preconcentration factor of 150-fold was obtained. The detection limits for Mn, Co and Ni were 40, 0.4 and 8.0 pg ml− 1, respectively, with relative standard deviations less than 6.0%. In order to validate the proposed method, two certified reference materials of human hair (GBW 07601) and mussel (GBW 08571), and water sample were analyzed with satisfactory results. The recoveries were between 95.0 and 114%.  相似文献   
47.
本文合成了一类新的含手性基团的β-二酮铜(Ⅱ)配合物,双[1-对烷氧基苯基-3-对-(2′甲基丁氧基)苯基-1,3-丙二酮]合铜(Ⅱ),经元素分析、红外光谱及比旋光度测定确定了结构。通过偏光显微镜下相变观察及DSC图谱,证实这些配合物没有液晶性,其原因可能在于分子的对称性不好  相似文献   
48.
结合材料化学实验课程自身的特点及材料化学实验教学的经验,系统阐述我院材料化学实验改革的思路,通过深化材料化学实验教学改革,提高任课教师的学术水平,更新教学内容,优化教学模式,推进教材的系统性建设,实现材料化学实验教学质量的提高,激发学生的学习热情与兴趣,进一步培养学生的创新能力。  相似文献   
49.
Self-assembled multilayer thin films have been prepared on Au substrate by alternate surface derivatization with L-cysteine hydrochloride and cupric perchlorate. The layer-by-layer structure at each step of multilayer formation was investigated by X-ray photoelectron spectroscopy. The measurements indicate that there are two structure modes in the multilayers. One is that Cu(2+) sandwiches between two amino acid groups. The other one is that Cu(+) is bonded through disulfide and thiolate. This process is also confirmed by cyclic voltammetry of Cu ion at different self-assembled multilayers. Steps further on will lead to repeated multilayer films.  相似文献   
50.
利用傅立叶变换红外(FT-IR)和拉曼(FT-Raman)光谱研究了高浓度磷脂酰胆碱(PC)与牛血清白蛋白(BSA)的相互作用,及Eu3+对该作用的影响.FT-IR结果显示,PC/BSA混合体系中二者的相互作用主要发生在PC头部极性基团,且这一作用随BSA含量的增加而增强,作用后蛋白质二级结构中α螺旋的比例有所增加. FT-Raman光谱说明PC与BSA的相互作用影响磷脂CH链的排列有序程度. PC/BSA/Eu3+体系的红外光谱显示, Eu3+与PC的磷氧键发生了强相互作用,并使蛋白α螺旋的比例进一步增加.  相似文献   
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