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161.
B. Boyarbay H. Çetin A. Uygun E. Ayyildiz 《Applied Physics A: Materials Science & Processing》2011,103(1):89-96
Thin films of polyaniline (PANI) titanium dioxide (TiO2) nanocomposites prepared with and without surfactant (tetradecyltrimethylammonium bromide, TTAB) were formed by spin coating
onto chemically cleaned p-type silicon substrates. The current–voltage characteristics of the Au/PANI
TiO
2/p-Si/Al and Au/PANI
TiO
2
TTAB/p-Si/Al heterojunctions had rectifying behavior with the potential barrier formed between the polymeric thin films and p-Si semiconductor, and they were analyzed on the basis of the standard thermionic emission (TE) theory. Cheung functions combined
with conventional forward I–V characteristics were used to obtain diode parameters such as barrier height, ideality factor and series resistance (R
s
). The values of barrier height, ideality factor and R
s
were found as 0.496±0.003 eV, 2.313±0.067 and 23.633±7.554 Ω for the Au/PANI
TiO
2/p-Si/Al device; 0.494±0.003 eV, 2.167±0.018 and 12.929±2.217 Ω for the Au/PANI
TiO
2
TTAB/p-Si/Al device. In addition, the energy distributions of the interface state density of the devices were determined from the forward
I–V characteristics by taking into account the bias dependence of the ideality factor and barrier height. It was seen that the
PANI
TiO
2
TTAB/p-Si device had slightly higher interface state density values than those of the PANI
TiO
2/p-Si device. 相似文献
162.
Ionics - Poly(vinylidene fluoride) (PVDF)/sodium hydrogen carbonate (NaHCO3)-based microporous polymer membranes were prepared by salt leaching. In this study, lithium-trifluoromethane sulfonate... 相似文献
163.
Hüseyin Karaca Devrim Türker Murat Teker 《Journal of Dispersion Science and Technology》2013,34(12):1800-1807
AbstractIn this study the effect of the dose and particle size of the adsorbent, initial dye concentration, initial pH, contact time and temperature were investigated for the removal of by means of fly ash (FA) methylene blue (MB) from an aqueous solution. The FA dose was found to be 2.0?g and the under 270 mesh sized particles were found to be effective particles for adsorption. The adsorption process reached its maximum value at 0.5?mg/L dye concentration and attained equilibrium within 10?minutes. The adsorption isotherm was found to follow the Langmuir model. The estimated adsorption free energy (ΔGo), enthalpy change (ΔHo), and entropy change (ΔSo) for the adsorption process were ?37.77?kJ mol?1, ?13.44?kJ mol?1 and 122 J mol?1 K?1 respectively at 298 K. The maximum adsorption capacity is 0,12?mg g?1 at 298 K and 0,07?mg g?1 at 398 K. The adsorption process was exothermic, feasible and spontaneous. The positive value of ΔSo shows the affinity of FA for MB while the low value of ΔGo suggests a physical adsorption process. 相似文献
164.
Arca Anil Omer Faruk Sadak Bartu Karakurt Dr. Yusuf Kocak Dr. Igor Lyubinetsky Prof. Dr. Emrah Ozensoy 《Chemphyschem》2023,24(13):e202200787
Understanding the activation of CO2 on the surface of the heterogeneous catalysts comprised of metal/metal oxide interfaces is of critical importance since it is not only a prerequisite for converting CO2 to value-added chemicals but also often, a rate-limiting step. In this context, our current work focuses on the interaction of CO2 with heterogeneous bi-component model catalysts consisting of small MnOx clusters supported on the Pd(111) single crystal surface. These metal oxide-on-metal ‘reverse’ model catalyst architectures were investigated via temperature programmed desorption (TPD) and x-ray photoelectron spectroscopy (XPS) techniques under ultra-high vacuum (UHV) conditions. Enhancement of CO2 activation was observed upon decreasing the size of MnOx nanoclusters by lowering the preparation temperature of the catalyst down to 85 K. Neither pristine Pd(111) single crystal surface nor thick (multilayer) MnOx overlayers on Pd(111) were not capable of activating CO2, while CO2 activation was detected at sub-monolayer (∼0.7 ML) MnOx coverages on Pd(111), in correlation with the interfacial character of the active sites, involving both MnOx and adjacent Pd atoms. 相似文献
165.
Hamide Filiz Ayyildiz Fakhar N. Memon Irfan Ali Mangi Huseyin Kara 《Journal of separation science》2023,46(14):2200914
Multimode chromatographic separations are highly desirable in pharmaceutical and environmental sciences. Current study deals with the application of newly developed mixed-mode end capped-immobilized humic acid onto an aminopropyl silica based chromatographic column for separation and identification of six drugs belonging to different therapeutic groups for its applicability in pharmaceutical industries. For this, central composite design was used to evaluate the separation and resolution by optimization of three most effective parameters (acetonitrile%, flow rate, and pH of mobile phase). Second-order quadratic model was used to evaluate their effect on resolution of peaks; the probability value (<0.05) obtained from analysis of variance suggested the best applicability of the model. Desirability function was applied to calculate optimum conditions (44.8% acetonitrile, 1.75 mL/min of flow rate, and 7.5 pH) required to achieve maximum separation with good resolution within 11 min. The method was validated for linearity, precision accuracy, selectivity, and sensitivity. The results revealed a highly precise (coefficient of variance > 1%), linear (R2 = 0.99), and highly selective method. Moreover, the limit of detection/quantification values revealed acceptable sensitivity of the method. The developed column was compared for its efficiency with a commercially available column and found to be highly applicable for industrial applications. 相似文献