Monotone Chemical Reaction Networks

We analyze certain chemical reaction networks and show that every solution converges to some steady state. The reaction kinetics are assumed to be monotone but otherwise arbitrary. When diffusion effects are taken into account, the conclusions remain unchanged. The main tools used in our analysis come from the theory of monotone dynamical systems. We review some of the features of this theory and provide a self-contained proof of a particular attractivity result which is used in proving our main result.     

Crystal and molecular structure of nitrosyl(1,10-phenanthroline)-bis(triphenylphosphine)iridium(I) Dihexafluorophosphate, [Ir(NO)(phen)(PPh3)2][PF6]2

Summary The structure of [Ir(NO)(phen)(PPh₃)₂][PF₆]₂ has been determined from x-ray diffractometer data. The compound crystallizes in space groupPnam with four molecules in a unit cell witha = 19.924(12),b = 14.793(9) andc = 16.348(9) A. Full-matrix least-squares refinement has led to a final R value of 0.061 for the 4796 observed reflections. The structure consists of well-separated ions, and the geometry around the metal is trigonal bipyramidal with nitrosyl and bidentate 1,10-phenanthroline (in spite of the very narrow bite angle of 75.8°) ligands occupying the equatorial positions and the triphenylphosphine ligands the axial positions. The cation has an imposed crystallographicm symmetry. Important bond lengths are as follows: Ir-P, 2.391(3): Ir-N (nitrosyl) 1.700(12): Ir-N (1,10-phenanthroline) 2.103(12) and 2.142(11): N-O, 1.201(18)A. The nitrosyl ligand is linear [Ir-N-O = 179.9(9)°] so that this complex can be formulated as an NO⁺ complex of iridium(I).     

Preparation of Nanoelectrode Ensembles by Assembly of Nano—Silver Colloid on Gold Surface

A novel method for preparing silver nanoelectrode ensembles(SNEEs) and gold nanoelectrode ensembles (GNEEs) has been developed. Silver colloid particles were first absorbed to the gold electrode surface to form a monolayer silver colloid. N-hexadecyl nercaptan was then assembled on the electrode to form a thoil monolayer on which hydrophilic ions cannot be transfered. The SNEEs was prepared by removing thiol from silver colloid surface through applying and AC voltage with increasing frequency at 0.20V(vs.SCE). Finally,GNEEs was obtained by immersing a SNEEs into 6 mol/L HNO3 to remove the silver colloid particles. By comparison with other methods such as template method ect., this method enjoys some advantages of lower resistance, same diameter,easy preparation,controllable size and density.     

立方介孔相含钇氧化硅的合成与表征

以低浓度的十六烷基三甲基溴化铵为结构导向剂,在碱性条件下通过水热法合成了具有立方结构的含钇Y MCM 48介孔分子筛材料。XRD测试表明当Y/Si<0.05时可以获得典型的长程有序介孔立方结构相,随Y/Si比的增加,晶胞参数的增大和红外吸收光谱(FTIR)的变化为Y进入介孔分子筛骨架中提供了有力证据。N2吸附-脱附实验给出这种立方介孔材料的BET表面积为1180m2·g-1,BJH平均孔径为3.4nm。紫外 可见漫反射光谱(UV vis)证明钇以一种六配位的形式存在。X射线光电子能谱(XPS)进一步证明钇以三价形式存在于立方介孔分子筛骨架中。     

三甘氨酸双11钨硅双核稀土杂多配合物的合成与性质

利用一缺位杂多酸对一维链式配合物的断链取代反应,合成了未见文献报道的以甘氨酸为桥联配体的双核稀土杂多配合物,其结构简式为K₁₀[(O₃₉W₁₁Si)RE(Gly)₃RE(SiW₁₁O₃₉)]·9H₂O(RE=La,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Y;Gly=NH₃⁺CH₂COO<     

Mixed ligand system of cysteine and thioglycolic acid assisting in the synthesis of highly luminescent water-soluble CdTe nanorods

Highly luminescent water-soluble CdTe nanorods were prepared with the assistance of the mixed ligand system of cysteine and thioglycolic acid; the aspect ratio and photoluminescence of the CdTe nanorods could be controlled by the refluxing time.     

卟啉类光敏剂在染料敏化太阳能电池中的应用

染料敏化太阳能电池结合了染料光敏剂和无机半导体的优势，具有较宽的光谱响应范围，制造工艺简单、成本较低，对环境友好，应用前景广阔，因而备受人们的关注。本文以卟啉配合物为主线，介绍光敏太阳能电池的基本构造和光电原理，从改善电池性能的角度，综述了各种卟啉类光敏剂在染料太阳能电池中的应用，讨论了卟啉配合物及其超分子结构对光电转化率的影响机理。     

Siloxane-Based Nanobuilding Blocks by Reaction Between Silanediol and Trifunctional Silicon Alkoxides

The preparation of nanostructured organic-inorganic materials by assembling of nanobuilding blocks allows controlling the extent of phase interaction, which in its turn governs structure-properties relationships. We present here the synthesis of siloxane-based nanobuilding blocks prepared by reacting diphenylsilanediol with vinyltriethoxysilane and triethoxysilane. The reaction products were obtained by non-hydrolytic condensation between silanediol and ethoxide groups in inert atmosphere, in the presence of pyridine, triethylamine or butyl lithium. Different synthetic conditions were examined by means of ATR-FTIR and NMR spectroscopies, showing the formation of siloxane bonds. In the case of triethoxysilane the reaction carried out in the presence of pyridine leads to Si–H bond preservation in the final product. Air stable products with improved Si–O–Si hydrolytic stability can be obtained by removal of the base after the reaction completion. The condensation products can be described as a mixture of siloxane rings involving difunctional and trifunctional silicon units.