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Three-dimensional Network Structure (three-dimensional + network_structure)
Selected AbstractsEffects of interactions among polyaniline, camphorsulfonic acid and silica on the structure and properties of their conductive hybridsPOLYMER ENGINEERING & SCIENCE, Issue 3 2008Hsun-Tsing Lee In this work, the effects of interactions among polyaniline (PAn), camphorsulfonic acid (CSA), and silica on the structure and properties of their sol-gel hybrids are investigated. These interactions were revealed by FTIR, UV,vis spectra, and XRD patterns. The interaction between PAn and CSA raises conductivities of the CSA-doped PAn/SiO2 (c-PAn/SiO2) hybrids. Moreover, the hydrogen bonding interaction between c-PAn and silicic acid (precursor of SiO2) leads to a less degree of three-dimensional network structure of the SiO2 component in a hybrid with higher PAn content. In addition, because of the interactions among CSA, Pan, and SiO2, the conductive c-PAn-rich phase distributes uniformly in the hybrid and thermal resistance of the hybrid is enhanced consequently. Besides, the c-PAn/SiO2 hybrid with higher SiO2 content exhibits more significant blue-shift of its polaron band, lower conductivity, and higher thermal resistance. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers [source] A new adamantanecarboxylate coordination polymer: poly[[(,3 -adamantane-1,3-dicarboxylato)aquadioxidouranium(VI)] monohydrate]ACTA CRYSTALLOGRAPHICA SECTION C, Issue 8 2010Julia A. Rusanova The title compound, {[U(C12H14O4)O2(H2O)]·H2O}n, is the first actinide complex featuring adamantanecarboxylate ligands. The metal ion possesses a pentagonal,bipyramidal UO7 coordination involving two axial oxide ligands [U,O = 1.732,(5) and 1.764,(5),Å] and five equatorial O atoms [U,O = 2.259,(5),2.494,(4),Å] of aqua and carboxylate ligands. The latter display pseudo-chelating and bridging coordination modes of the carboxylate groups that are responsible for the generation of the centrosymmetric discrete uranium,carboxylate [UO2(,- RCOO)2UO2] dimers [U...U = 5.5130,(5),Å] and their connection into one-dimensional chains. Hydrogen bonding involving two coordinated and two solvent water molecules [O...O = 2.719,(7),2.872,(7),Å] yields centrosymmetric (H2O)4 ensembles and provides noncovalent linkage between the coordination chains to generate a three-dimensional network structure. [source] Tetraaquabis(2-methoxybenzaldehyde isonicotinoylhydrazone)cadmium(II) dinitrateACTA CRYSTALLOGRAPHICA SECTION C, Issue 10 2007Zhongwu Fu The CdII centre in the title complex, [Cd(C14H13N3O2)2(H2O)4](NO3)2, occupies a crystallographic inversion centre and is coordinated by two donor N atoms from two 2-methoxybenzldehyde isonicotinoylhydrazone ligands and by four O atoms from four coordinated water molecules, giving a slightly distorted octahedral geometry. There is an extended three-dimensional network structure resulting from O,H...O hydrogen bonds between coordinated water and nitrate anions, and between coordinated water and carbonyl O atoms, and from N,H...O hydrogen bonds between NH groups and nitrate O atoms. [source] High Surface Area, Mesoporous, Glassy Alumina with a Controllable Pore Size by Nanocasting from Carbon AerogelsCHEMISTRY - A EUROPEAN JOURNAL, Issue 5 2005Wen-Cui Li Dr. Abstract A strategy to synthesize amorphous, mesoporous alumina by nanocasting has been developed, involving carbon aerogel as a hard template and aluminum nitrate solution as an alumina precursor. The alumina generated exhibits small, transparent granules with a 3,6 mm diameter and has inherited the three-dimensional network structure of the carbon template. The mesopore surface area of the alumina can be as high as 365 m2,g,1, and the pore volume reaches 1.55 cm3,g,1 after calcination at 600,°C in air for 8 h. The pore parameters can be varied within a certain range by variation of the carbon aerogel template and the loading amount of the alumina precursor. At high loadings, the obtained glassy alumina clearly has a bimodal pore size distribution in the mesopore range. [source] | ||||||||||