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IR Techniques (ir + techniques)
Selected AbstractsSelf-Assembly and Metallization of Resorcinarene Microtubes in Water,ADVANCED FUNCTIONAL MATERIALS, Issue 24 2008Yan Sun Abstract Amphiphilic resorcinarene-based multiwalled microtubes, millimetres in diameter and centimetres in length, are generated in water. The thickness of the tube wall approaches 300,nm. Their self-assembly properties are investigated using transmission electron microscopy, scanning electron microscopy, atomic-force microscopy, dynamic light scattering, X-ray diffraction, UV-vis spectra, and Fourier transform IR techniques. From these studies, the structures critical for the self-assembly of resorcinarene into microtubes in aqueous media are determined. Furthermore, the study manifests a feasible method that aims to completely change the structure from a microtube to a sheet-like morphology by selectively eliminating key groups. Subsequently, resorcinarene-capped water-soluble gold nanoparticles (AuNPs) are fabricated. By utilizing the obtained microtubes as a template, a gold/organic microtubular composite is successfully prepared. [source] Preparation and thermal decomposition reaction kinetics of a dysprosium(III) p -chlorobenzoate 1,10-phenanthroline complexINTERNATIONAL JOURNAL OF CHEMICAL KINETICS, Issue 2 2008Jian Jun Zhang The title complex [Dy(p -ClBA)3Phen]2·2H2O was synthesized, where p -ClBA is p -chlorobenzoate and Phen is 1,10-phenanthroline. The complex was characterized by various techniques including elemental analysis, IR, XRD, and molar conductance. The thermal decomposition of the complex was studied under the nonisothermal condition by TG-DTG and IR techniques. The kinetic parameters of dehydration process were obtained from the analysis of DSC curves of the complex by the NL-DIF and Popescu methods, respectively. © 2007 Wiley Periodicals, Inc. 40: 66,72, 2008 [source] Synthesis and thermal decomposition reaction kinetics of complexes of [Sm2(m -ClBA)6(phen)2],·,2H2O and [Sm2(m -BrBA)6(phen)2],·,2H2OINTERNATIONAL JOURNAL OF CHEMICAL KINETICS, Issue 2 2007Jian Jun Zhang Complexes of [Sm2(m -ClBA)6(phen)2],·,2H2O and [Sm2(m -BrBA)6(phen)2],·,2H2O (m -ClBA = m -chlorobenzoate, m -BrBA = m -bromobenzoate, and phen = 1,10-phenanthroline) were prepared and characterized by elemental analysis and IR spectra. The thermal decomposition processes of the two complexes were studied by means of TG,DTG and IR techniques. Their thermal decomposition kinetics were investigated from the analysis of the TG and DTG curves by jointly using a new method proposed by us and a newly nonlinear isoconversional integral method. © 2006 Wiley Periodicals, Inc. Int J Chem Kinet 39: 67,74, 2007 [source] Polymerization of linseed oil with phenolic resinsJOURNAL OF APPLIED POLYMER SCIENCE, Issue 2 2010Gökhan Çayl Abstract In this study, linseed oil was directly polymerized with different oil soluble resoles. p- Ethyl (PEP), p-tertiary butyl (PTB), p-tertiary octyl (PTO), and p- phenyl (PPP) phenols were separately reacted with formaldehyde to give linseed oil soluble resoles. These were then reacted with linseed oil to give transparent rubbery polymers. A model reaction was performed with methyl oleate and PTB phenol resole to clarify the reaction mechanism. Reaction products were characterized with 1H-NMR and IR techniques. Spectral examination of the model reaction showed that polymerization reaction proceeded via ene reaction of the quinone methide formed at the end group of the resole with the allylic positions of the fatty ester. Rubbery polymers were obtained with linseed oil using 10 to 40% of the different resoles. Hard, load bearing and tough materials were obtained at 40% phenolic resin loading. Mechanical properties of the materials were characterized by dynamic mechanical analyzer (DMA) and stress,strain tests. The best mechanical and thermal properties were obtained with PEP resole which showed a storage modulus of 350 MPa and a tan , peak at 65°C. Storage moduli of 275, 250, and 30 were obtained for PPP, PTB, and PTO resoles-linseed oil polymers, respectively. At the same phenolic resin loading, elongation at break and swelling ratios in CH2Cl2 increased with the longer alkyl substitution on the resole resins. The highest thermal stability was observed by PEP resole,linseed oil polymer which has a 5% weight loss temperature of 340°C as determined by TGA. The lowest thermal stability was observed for PTB resole-linseed oil polymer at 220°C. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] Investigating information retrieval support techniques for different information-seeking strategiesJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 8 2010Xiaojun Yuan We report on a study that investigated the efficacy of four different interactive information retrieval (IIR) systems, each designed to support a specific information-seeking strategy (ISS). These systems were constructed using different combinations of IR techniques (i.e., combinations of different methods of representation, comparison, presentation and navigation), each of which was hypothesized to be well suited to support a specific ISS. We compared the performance of searchers in each such system, designated "experimental," to an appropriate "baseline" system, which implemented the standard specified query and results list model of current state-of-the-art experimental and operational IR systems. Four within-subjects experiments were conducted for the purpose of this comparison. Results showed that each of the experimental systems was superior to its baseline system in supporting user performance for the specific ISS (that is, the information problem leading to that ISS) for which the system was designed. These results indicate that an IIR system, which intends to support more than one kind of ISS, should be designed within a framework which allows the use and combination of different IR support techniques for different ISSs. [source] Synthesis and Thermal Decomposition Kinetics of the Complex of Samarium p -Methylbenzoate with 1,10-PhenanthrolineCHINESE JOURNAL OF CHEMISTRY, Issue 1 2007Jian-Jun Zhang Abstract The complex [Sm(p -MBA)3phen]2 (p -MBA, p -methylbenzoate; phen, 1,10-phenanthroline) was prepared and characterized by elemental analysis, IR and UV spectra. The thermal decomposition process of [Sm(p - MBA)3phen]2 was studied under a static air atmosphere by TG-DTG and IR techniques. Thermal decomposition kinetics was investigated employing a newly proposed method, together with the integral isoconversional non-linear method. Meanwhile, the thermodynamic parameters (,H,, ,G, and ,S,) were also calculated. The lifetime equation at mass-loss of 10% was deduced as ln ,=,24.7825+18070.43/T by isothermal thermogravimetric analysis. [source] | |||||||||||||