Probe metal binding mode of imine covalent organic frameworks: cycloiridation for (photo)catalytic hydrogen evolution from formate

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.     

CuO／活性炭和Fe2O3／活性炭催化还原NO

ＣｕＯ／活性炭和Ｆｅ_２Ｏ_３／活性炭催化还原ＮＯ高志明，赵震，杨向光，吴越（中国科学院长春应用化学研究所长春１３００２２）关键词活性炭，还原，ＮＯ，氧化铜，氧化铁目前，对固定源的ＮＯ处理是采用Ｖ２Ｏ５／ＴｉＯ２作催化剂，ＮＨ３作还原剂的选择催化还原方...     

Structure and properties of a novel 3D straight-channel polyoxovanadate and an unexpected trimeric barbiturate obtained by hydrothermal reactions

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.     

Direct optical detection of singlet oxygen from a single cell

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.     

The use of carbon nanofibers microcolumn preconcentration for inductively coupled plasma mass spectrometry determination of Mn,Co and Ni

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%.     

一类新的手性β-二酮铜(Ⅱ)配合物合成及性质 Ⅰ.( )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)

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     

AN/St悬浮共聚体系中AN在水/油两相间分配及其对共聚物组成的影响

研究了丙烯腈/苯乙烯(AN/St)悬浮共聚体系中AN在水/油两相间的分配及其对AN/St共聚物组成的影响.结果表明,AN分配于水/油两相间,使油相AN的含量低于相同单体配料比的本体聚合,导致生成的AN/St共聚物组成偏离本体共聚.为了准确预测进而控制AN/St悬浮共聚物的组成,提出了在考虑AN相分配的基础上计算AN/St悬浮共聚物组成的模型.计算结果与实验值一致,计算中用到的油相实际竞聚率与本体聚合相同,但该悬浮聚合的表观竞聚率随水/油比的变化而发生较大改变.     

材料化学实验课程体系的改革与建设

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。     

General solution for Poisson-Boltzmann equation in semiinfinite planar symmetry

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.