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A solid polymer electrolytes (SPE) comprising blend of poly(ethylene oxide; PEO) and epoxidized natural rubber as a polymer
host and LiCF3SO3 as a dopant were prepared by solution-casting technique. The SPE films were characterized by field emission scanning electron
microscopy to determine the surface morphology, X-ray diffraction, and differential scanning calorimeter to determine the
crystallinity and thermogravimetric analysis to confirm the mass decrease caused by loss of the solvent. While the presence
of the complexes was investigated by reflection Fourier transform infrared (ATR-FTIR) spectroscopy. Electrochemical impedance
spectroscopy was conducted to obtain ionic conductivity. Scanning electron microscopy analysis showed that a rough surface
morphology of SPE became smoother with addition of salt, while ATR-FTIR spectroscopy analysis confirmed the polymer salt complex
formation. The interaction occurred between the salt, and ether group of polymer host where the triple peaks of ether group
in PEO merged and formed one strong peak at 1,096 cm−1. Ionic conductivity was found to increase with the increase of salt concentration in the polymer blend complexes. The highest
conductivity achieved was 1.4 × 10−4 Scm−1 at 20 wt.% of LiCF3SO3, and this composition exhibited an Arrhenius-like behavior with the activation energy of 0.42 eV and the preexponential factor
of 1.6 × 103 Scm−1. 相似文献
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The Ba(Ce0.8Zr0.2)0.95Yb0.05O2.975 ceramics electrolyte was prepared via a Pechini method using metal nitrate salts as starting materials. An optimum annealing
temperature of 1,400 °C was needed to obtain a pure perovskite-like phase with orthorhombic structure. Particle size distribution
showed a bimodal distribution that corresponds to the loose powders and agglomerates size. Scanning electron micrograph revealed
that the loose powders were in the nanosize range (70–200 nm). These ultrafine loose powders enhanced the densification of
a pellet with relative density ∼95% obtained at 1,400 °C. The sample formed clear and compact grains with submicron sizes.
Impedance results showed that the impedance semicircle of the grain was observed only at T ≤ 250 °C. The introduction of 20 mol% Zr improved the chemical stability of BaCe0.95Yb0.05O2.975 sample in atmosphere containing carbon dioxide at 600 °C. The sample also exhibited high proton conductivity in wet hydrogen. 相似文献
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Nadia Abdullah Abd Rahim Abu Talib Helmey Ramdhaney Mohd Saiah Abdul Aziz Jaafar Mohamad Amran Mohd Salleh 《Experimental Thermal and Fluid Science》2009,33(4):561-578
Thermochromic liquid crystals (TLCs) have been widely employed by researchers in heat transfer and fluid flow communities as a reliable and non-intrusive temperature measurement tool due to their unique optical properties such as birefringence, optical activity, circular dichroism and selective reflection of colours in the visible spectrum as function of temperature. The use of narrowband TLCs are attractive for temperature and heat transfer measurements due to their higher precision in temperature measurements and due to the fact that narrowband TLCs are less affected by variations in illumination-viewing angles and illumination disturbances. Narrowband TLCs have been used with full intensity-matching methods to provide robust image processing for measurements of thermal parameters in transient heat transfer tests. Calibration of narrowband TLCs is necessary in order to obtain the intensity-temperature relationship of the TLCs. Film thickness is one of the factors which affects calibrations of TLCs. In this research, film thicknesses of 10, 20, 30, 40 and 50 μm were investigated on green intensity-based calibrations of R35C1W TLC during heating and cooling. Results showed an increase in magnitude of peak green intensity with increasing film thickness, with a percentage increase of nearly 18% when film thickness increased from 10 to 50 μm. Results also showed an inconsistent shift in temperature at which peak green intensity occurs, with a maximum shift of 0.40 °C, suggesting that film thickness effects may be insignificant for narrowband TLCs compared with wideband TLCs. A theoretical method for estimating the volume of TLC coating required to achieve a desired film thickness has also been described in this paper, based on the surface area and dry solids content of the TLC. The method is easily implemented and applicable for sprayable TLC coatings. 相似文献
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Amir Reza Sadrolhosseini Mohd Maarof Moksin W. Mahmood Mat Yunus Zainal Abidin Talib Mahnaz M. Abdi 《Optical Review》2011,18(4):331-337
Copper corrosion is one of the important parameters used for evaluating the quality of biodiesel. In this work, a polypyrrole-chitosan
sensing layer was utilized for the detection of Cu2+ in biodiesel using the surface plasmon resonance technique. With the sensitivity of this sensor being about 0.1 ppm, different
corrosion levels could be recognized in samples that were classified as class 1a according to the standard copper strip test. 相似文献
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Development and validation of a rapid ultra high performance liquid chromatography with tandem mass spectrometry method for the simultaneous determination of darunavir,ritonavir, and tenofovir in human plasma: Application to human pharmacokinetics 下载免费PDF全文
Ambavaram Vijaya Bhaskar Reddy Jafariah Jaafar Azmi Bin Aris Zaiton Abdul Majid Khalid Umar Juhaizah Talib Gajulapalle Madhavi 《Journal of separation science》2015,38(15):2580-2587
A sensitive ultra high performance liquid chromatography with tandem mass spectrometry method was developed for the simultaneous determination of darunavir, ritonavir and tenofovir in human plasma. Sample preparation involved a simple liquid–liquid extraction using 200 μL of human plasma extracted with methyl tert‐butyl ether for three analytes and internal standard. The separation was accomplished on an Acquity UPLC BEH C18 (50 mm x 2.1 mm, 1.7 μm) analytical column using gradient elution of acetonitrile/methanol (80:20, v/v) and 5.0 mM ammonium acetate containing 0.01% formic acid at a flow rate of 0.4 mL/min. The linearity of the method ranged between 20.0 and 12 000 ng/mL for darunavir, 2.0 and 2280 ng/mL for ritonavir, and 14.0 and 1600 ng/mL for tenofovir using 200 μL of plasma. The method was completely validated for its selectivity, sensitivity, linearity, precision and accuracy, recovery, matrix effect, stability, and dilution integrity. The extraction recoveries were consistent and ranged between 79.91 and 90.04% for all three analytes and internal standard. The method exhibited good intra‐day and inter‐day precision between 1.78 and 6.27%. Finally the method was successfully applied for human pharmacokinetic study in eight healthy male volunteers after the oral administration of 600 mg darunavir along with 100 mg ritonavir and 100 mg tenofovir as boosters. 相似文献
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Mahmoud Al‐Talib Hasan Tashtoush Areej Al‐Ghoul Burkhard Ziemer Ulrich Koert 《Journal of heterocyclic chemistry》2005,42(2):287-288
Phenylmalonic acid dihydrazide reacted with 2,4‐pentanedione to give, unexpectedly, 5,7‐dimethyl‐1,3‐dioxo‐2‐phenyl‐2,3‐dihydro‐1H‐pyrazolo[1,2‐a]pyrazole‐4‐ylium 5. The structure of the product is confirmed by X‐ray crystallography. 相似文献
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Yasser Shahzad Maimoona Maqbool Talib Hussain Abid Mehmood Yousaf Ikram Ullah Khan Tariq Mahmood 《Natural product research》2020,34(1):16-25
AbstractThis study was aimed at developing orodispersible films of citalopram using combination of natural and semisynthetic polymers for patients with swallowing problem. Okra biopolymer and moringa gum were utilized in combination with hydroxypropyl methylcellulose (HPMC) and pullulan. The disintegration time was less than 30?seconds and the drug content uniformity was 97.89–102.05% for all film formulations. Films formulated with HPMC (K15 and K4M) combination (F1) and combination of okra and HPMC K15 (F2) had superior mechanical properties as compared with F3 (okra and pullulan) and F4 (moringa gum and HPMC). Thermal analysis revealed stable formulations over the studied temperature range and the crystalline citalopram was completely or partially transformed into amorphous form as revealed by the differential thermal analysis, X-ray diffraction and scanning electron microscopy images. In conclusion, okra biopolymer could be used in combination with HPMC for the development of orodispersible films. 相似文献
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