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101.
Composite blending of ionic liquid–poly(ether sulfone) polymeric membranes: Green materials with potential for carbon dioxide/methane separation 下载免费PDF全文
The incorporation of imidazolium‐based ionic liquids into a poly(ether sulfone) (PES) polymeric membrane resulted in a dense and void‐free polymeric membrane. As determined through the ideal gas permeation test, the carbon dioxide (CO2) permeation increased about 22% compared to that of the pure PES polymeric membrane whereas the methane (CH4) permeation decreased tremendously. This made the CO2/CH4 ideal separation increase substantially by more than 100%. This study highlighted the utilization of imidazolium‐based ionic liquids in the synthesis of ionic liquid polymeric membranes (ILPMs). Two different ionic liquids were used to compare the CO2 separation performance through the membranes. The glass‐transition temperatures (Tgs) of ILPMs were found to be lower than the Tg of the pure PES polymeric membranes; this supported the high CO2 permeation of the ILPMs due to the increase in PES flexibility caused by ionic liquid addition. The results also draw attention to new trends of ionic liquids as a potential green candidates for future membrane synthesis. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43999. 相似文献
102.
Novel Poly(linolenic acid) Graft Copolymers: Synthesis,Characterization and Electrical Properties 下载免费PDF全文
Abdulkadir Allı Yurdagül Arı Muharrem Gökçen 《Journal of the American Oil Chemists' Society》2016,93(7):895-904
A poly(linolenic acid)‐g‐poly(tert‐butyl acrylate) graft copolymer was synthesized from polymeric linolenic acid peroxide possessing peroxide groups in the main chain by free radical polymerization of tert‐butyl acrylate. Graft copolymers having structures of poly(linolenic acid)‐g‐poly(caprolactone)‐g‐poly(tert‐butyl acrylate) were synthesized from polymeric linolenic acid, possessing peroxide groups on the main chain by the combination of free radical polymerization of tert‐butyl acrylate and ring‐opening polymerization of ε‐caprolactone in one‐pot. The obtained graft copolymers were characterized by proton nuclear magnetic resonance, gel permeation chromatography, thermal gravimetric analysis, differential scanning calorimetry, and scanning electron microscopy techniques. Furthermore, Au/n‐Si diodes were fabricated with and without poly(linolenic acid)‐g‐poly(caprolactone)‐g‐poly(tert‐butyl acrylate)‐4 to form a new interfacial polymeric layer for the purpose of investigating this polymer's conformity in electronic applications. Some main electrical characteristics of these diodes were investigated using experimental current–voltage measurements in the dark and at room temperature. 相似文献
103.
Ihsan Ali M. U. Islam M. S. Awan Mukhtar Ahmad M. Asif Iqbal 《Journal of Superconductivity and Novel Magnetism》2013,26(11):3277-3286
Nanostructured M-type hexaferrite Ba1?x Ca x Fe11.5Cr0.5O19 (x=0.0–0.5) powders have been synthesized by means of the sol-gel autocombustion method. The materials are characterized by differential scanning calorimetry, thermogravimetry, Fourier transform infra-red spectroscopy, X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, and vibrating sample magnetometry. X-ray diffraction analysis confirms the formation of M-type hexagonal phase and few traces of α-Fe2O3 are also observed. The c/a ratio falls in the expected range from a value of 3.97 to 3.94 of M-type hexaferrites. The average crystallite size is found to be in the range 15 to 36 nm, which is good enough to obtain the suitable signal-to-noise ratio in the high-density recording media. DC electrical resistivity at room temperature enhances up to 11.2×109 Ω?cm (x=0.4) and then drops upon increasing the Ca2+ contents further. The magnetic properties such as saturation magnetization (M s ), remanence (M r ), squareness ratio (M r /M s ) and coercivity (H c ) are calculated from the M–H-loops. The maximum magnetization and remanence reduces from a value of 52 to 33 and 33 to 16 emu/g, respectively, which attributes to the decrease of magnetic moment, and hence reduction in the superexchange interaction. The coercivity enhances from 4378 to 4706 Oe, which attributes to the increase in magnetocrystalline anisotropy due to the reduction of particle size. Owing to these properties, the synthesized nanomaterials can be considered useful for high-density recording media and permanent magnets. 相似文献
104.
Two studies test the assertion that anger, sadness, fear, pride, and happiness are typically narrated in different ways. Everyday events eliciting these 5 emotions were narrated by young women (Study 1) and 5- and 8-year-old girls (Study 2). Negative narratives were expected to engender more effort to process the event, be longer, more grammatically complex, more often have a complication section, and use more specific emotion labels than global evaluations. Narratives of Hogan’s (2003) juncture emotions anger and fear were expected to focus more on action and to contain more core narrative sections of orientation, complication, and resolution than narratives of the outcome emotions sadness and happiness. Hypotheses were confirmed for adults except for syntactic complexity, whereas children showed only some of these differences. Hogan’s theory that juncture emotions are restricted to the complication section was not confirmed. Finally, in adults, indirect speech was more frequent in anger narratives and internal monologue in fear narratives. It is concluded that different emotions should be studied in how they are narrated, and that narratives should be analyzed according to qualitatively different emotions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
105.
Muhammad Saleem Muhammad H. Sayyad Khasan S. Karimov Muhammad Yaseen Mukhtar Ali 《Journal of Materials Science》2009,44(5):1192-1197
In this study, an organic semiconductor 5,10,15,20-tetrakis(4′-isopropylphenyl) porphyrin (TIPP) was synthesized and investigated
as an active material in surface-type multifunctional sensor. As electrodes, 100 nm thick Ag films were deposited on 25 mm × 25 mm
glass substrate with 40 μm gap between them. Thin film of TIPP of area 15 mm × 15 mm was thermally sublimed to cover the gap
between the silver electrodes. Thickness of TIPP film was 100 nm. A change in electrical resistance and capacitance of the
fabricated device was observed with the increase in relative humidity (RH), temperature, and illumination. Hysteresis, response,
and recovery times were investigated over a wide range of RH (0–94%). Activation energy of the TIPP was estimated. An equivalent
circuit of the Ag/TIPP/Ag humidity, temperature, and illumination sensor was developed. Humidity, temperature, illumination
dependent capacitive, and resistive properties of this sensor make it promising for use in a humidity, temperature, and lux
multi-meters. 相似文献
106.
Synthesis of yttrium and cerium doped ZnO nanoparticles as highly inexpensive and stable photocatalysts for hydrogen evolution 总被引:1,自引:0,他引:1
Irshad Ahmad Muhammad Shoaib Akhtar Mian Faisal Manzoor Muhammad Wajid Muhammad Noman Ejaz Ahmed Mukhtar Ahmad Waheed Qamar Khan Anwar M.Rana 《中国稀土学报(英文版)》2021,39(4):440-445
Yttrium and cerium co-doped ZnO nanoparticles were synthesized by combustion route and characterized using X-ray diffraction(XRD),scanning electron microscopy(SEM),Brunauer-Emmett-Teller(BET),energy dispersive spectroscopy(EDS),X-ray photoelectron spectroscopy(XPS),UV-visible diffuse reflectance spectroscopy(UV-vis DRS),photoluminescence(PL)and electrochemical impedance spectroscopy(EIS)techniques.The introduction of yttrium ions has efficiently increased the relative percentage of Ce3+ions in ZnO.Yttrium and cerium co-doped ZnO shows efficient photo activity for hydrogen evolution(10.61 mmol/((g·h))higher than previously reported optimal value for rare earth codoped ZnO photocatalysts.This remarkably increased hydrogen evolution can be ascribed to the synergy between electronic anchoring effect of Y3+/Y2+and Ce4+/Ce3+redox couples.This report presents new idea for the synthesis of efficient photocatalyst using economical route and ion anchoring effect.The hydrogen evolution was also tested using Na2S and Na2SO3as electron donors under visible light illumination.The synthesized photocatalysts also exhibit high stability. 相似文献
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