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41.
Chin-Kuen Tai Pao-Ling Yeh Chun-Chi Chang Wen-Hao Chen Rong-Hou Wu Yu-Ma Chou Bo-Cheng Wang 《Research on Chemical Intermediates》2014,40(6):2355-2362
Recently, the organic synthesis and electronic device applications of π-conjugated polymer-based materials with low energy band gap (below 2 eV) and high values of incident photon to current efficiency have been presented. In the present study, the physical properties of polythiophene (PTH) and its derivative systems (PTs) were investigated as π-conjugated low energy band gap polymers. Density functional theory with periodic boundary condition (PBC), the B3LYP functional, and the 6-31G(d) basis set was applied to determine their geometric and electronic structures and corresponding energies (E HOMO, E LUMO, and E g = E LUMO ? E HOMO) from the monomer of thiophene and its derivatives for one-dimensional (1D) extension to polymer. The effects of 3-substitution in PTs including electron-donating (CH3–, C6H13–, OH–, Cl–, OCH3–, and CHO–) and electron-withdrawing groups (Cl–, CHO–, CN–, NO2–, CF3–, and COOH–) compared with PTH were investigated. According to the calculation results, PTs with electron-donating and electron-withdrawing substituents should exhibit red- and blue-shifts, respectively, compared with PTH. These calculation results show good agreement with experimental data and provide further information for molecular design considerations. 相似文献
42.
Micro-contact imprinting has been used to form thin-film molecular imprints of ovalbumin (OVA) in polymers supported on glass slides. Thermocalorimetric data was used to optimise the choice of functional monomer and cross-linker to maximise selectivity and minimise non-specific recognition.A polymer comprising polyethyleneglycol 400 dimethacrylate (95 vol.%) and methacrylic acid (5 vol.%) showed both maximum recognition for OVA when made as a molecularly imprinted polymer (MIP), and minimal recognition when made as a non-imprinted, i.e. control polymer. OVA rebinding to the molecularly imprinted polymer, from a buffered 2 µM OVA solution, was 1.55 × 10− 11 mol cm− 2, while the control polymer showed 10-fold less re-binding, i.e. 0.154 × 10− 11 mol cm− 2.Experiments in which human serum albumin (HSA), conalbumin, ovomucoid or lysozyme, were re-bound to the polymers, either as single proteins or in competition with OVA, showed them to have low affinity for the polymer formulation used. Of the competing proteins examined, in non-competitive binding experiments, HSA showed the greatest affinity 0.45 × 10− 11 mol cm− 2 for the OVA imprinted polymer. In two protein competition experiments, i.e. with OVA and a competing protein present at equal concentrations (2 µM), OVA binding to the OVA imprinted polymer was in all cases significantly greater than that of the competitor. 相似文献
43.
44.
This study investigates the influences of the microstructures and doping effect on electrical and optical properties of ZnO:Al
films deposited by sol–gel method. Experimental results showed that aluminum concentration affected the crystallite size obviously
and enhanced the relative intensity i
(002) faintly. Based on photoluminescence results, too much doping atoms generally can cause film crystallinity to deteriorate.
Hall measurements indicated the carrier concentration rose only to a certain level after several coating processes. According
to ellipsometric data, higher carrier mobility was mainly caused by the escalating density resulted by the increasing film
thickness. However, the formation mechanism of charge carrier by doping technique in the sol–gel process is different from
that of sputtering technique. The best sample having a sheet resistance of 182 Ω/sq and a transmittance of over 80% in visible
region was obtained in aluminum concentration of 1.0 at.%. 相似文献
45.
C. -W. Chang Y. -C. Chou J. -M. Tseng M. -Y. Liu C. -M. Shu 《Journal of Thermal Analysis and Calorimetry》2009,95(2):639-643
Many concerns over unsafe or unknown properties of multi-walled carbon nanotubes (MWNTs) have been raised. The thermal characteristics
regarding stability would represent potential hazards during the production or utilization stage and could be determined by
calorimetric tests for various thermokinetic parameters. Differential scanning calorimetry (DSC) was employed to evaluate
the thermokinetic parameters for MWNTs at various compositions.
Thermoanalytical curves showed that the average heat of decomposition (ΔH
d) of the MWNTs samples in a manufacturing process was about 31,723 J g−1, by identifying them as an inherently hazardous material. In this study, significant thermal analysis appeared in the presence
of sulfuric acid (H2SO4). From the DSC experiments, the purification process of MWNTs could induce an unexpected reaction in the condition of batch
addition with reactants of H2SO4. The results can be applied for designing emergency relief system and emergency rescue strategies during a perturbed situation
or accident. 相似文献
46.
Yu Lin Song Chih Hsiao Cheng Luh-Maan Chang Chia-Fone Lee Yuan Fang Chou 《Applied Acoustics》2011,(12):949-952
Mono-disperse polycarbonate (PC) nanoparticles 20 nm in diameter was spray coated on silicon substrate using a novel high-frequency ultrasonic nozzle. Specifically, Bisphenol-A polycarbonate with a molecular weight (Mw) of approximately 6.4 × 104 g/mol was first dissolved in pyridine. The resulting solution was sprayed into surfactant-containing de-ionized (DI) water using a 300 kHz silicon-based multiple-Fourier horn nozzle (MFHN). As pyridine was extracted into the water, PC nanoparticles formed but remained dispersed. This suspension of PC nanoparticles was then sprayed onto a silicon substrate using a 500 kHz 3-Fourier horn nozzle. Scanning electron microscopy (SEM) of the dried substrate revealed that PC nanoparticles were spread uniformly with no aggregation. 相似文献
47.
Shih-Feng Tseng Wen-Tse HsiaoDonyau Chiang Kuo-Cheng HuangChang-Pin Chou 《Applied Surface Science》2011,257(16):7204-7209
The fluorine-doped tin oxide (FTO) thin film deposited on a soda-lime glass substrate was annealed by a defocus ultraviolet (UV) laser irradiation at ambient temperature. The mechanical and optoelectric properties of FTO films annealed by using the various laser processing parameters were reported. After the FTO films were subjected to laser post-annealing, the microhardness were slightly less but the reduced modulus values were larger than that of unannealed FTO films, respectively. The average optical transmittance in the visible waveband slightly increased with increasing the laser annealing energy and scan speed. Moreover, all the sheet resistance of laser annealed films was less than that of the unannealed ones. We found that the sheet resistance decrease was obviously influenced by annealing. The suitable annealing conditions could maintain the film thickness and relief the internal stress generated in the film preparation process to improve the electrical conductivity via decreasing laser energy or increasing scan speed. 相似文献
48.
49.
Reagen Ying‐Tai Su Li‐Ko Chiu Shan‐Wei Weng Ying‐Shiun Chou Raymond Chien‐Chao Tsiang 《Journal of Polymer Science.Polymer Physics》2012,50(4):280-288
White polymeric light‐emitting diode (WPLED) based on a single polymer, poly(3‐hexylthiophene‐alt‐9,9‐dioctylfluorene) (PTAF), has been successfully demonstrated. This conjugated alternating copolymer, PTAF, comprises 50 mol % of 3‐hexylthiophene which is an orange‐red color chromophore and 50 mol % 9,9‐dioctylfluorene which is a bluish‐green color chromophore. It was synthesized by Suzuki cross‐coupling reaction and has a molecular weight of 15,021 and polydispersity of 1.36. Nanocomposite consisting PTAF and graphene nanosheets enhances the optoelectronic properties and the device fabricated with a configuration of ITO/PEDOT:PSS/(PTAF + 1% graphene)/Ca/Al shows two‐color white electroluminescence with CIE 1931 coordinates of (0.28, 0.34). The white luminescence from a single polymer affords the WPLED device a simple structure and low fabrication cost. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011 相似文献
50.