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101.
Syed Waqar Hasan Suhana Mohd. Said Mohd. Faizul Mohd Sabri Hasan Abbass Jaffery Ahmad Shuhaimi Bin Abu Bakar 《大分子材料与工程》2018,303(3)
In this work, thermally insulating composite mats of poly(vinylidene fluoride) (PVDF) and polyacrylonitrile (PAN) blends are used as the separator membranes. The membranes improve the thermal‐to‐electrical energy conversion efficiency of a thermally driven electrochemical cell (i.e., thermocell) up to 95%. The justification of the improved performance is an intricate relationship between the porosity, electrolyte uptake, electrolyte uptake rate of the electrospun fibrous mat, and the actual temperature gradient at the electrode surface. When the porosity is too high (87%) in PAN membranes, the electrolyte uptake and electrolyte uptake rate are significantly high as 950% and 0.53 µL s?1, respectively. In such a case, the convective heat flow within the cell is high and the power density is limited to 32.7 mW m?2. When the porosity is lesser (up to 81%) in PVDF membranes, the electrolyte uptake and uptake rate are relatively low as 434% and 0.13 µL s?1, respectively. In this case, the convective flow shall be low, however, the maximum power density of 63.5 mW m?2 is obtained with PVDF/PAN composites as the aforementioned parameters are optimized. Furthermore, multilayered membrane structures are also investigated for which a bilayered architecture produces highest power density of 102.7 mW m?2. 相似文献
102.
Magdy El-Hagary Said H. Moustafa Hany Hashem Essam R. Shaaban Mohamed Emam-Ismail 《Journal of the American Ceramic Society》2019,102(8):4737-4747
Mn-doped HgO nanostructured thin films (Hg1-xMnxO) have been prepared using electron beam evaporation technique on Corning glass (1022) substrate at room temperature with different concentrations x = 0, 0.015, 0.05, 0.1, 0.15, and 0.2. The microstructural, morphological, semiconducting, and optoelectronic properties of the films have been investigated. The X-ray diffraction spectra suggest a hexagonal wurtzite type structure with lattice parameters decreased with increasing Mn content. It was found that the average particle size of the films decreases with increasing Mn doping which is confirmed by FE-SEM and AFM micrographs. The optical band gap of the investigated Mn-doped HgO nanocrystalline films is determined from the absorption coefficient and found to increase with the increase of Mn concentration which is attributed to the sp-d exchange interaction and/or the quantum confinement effect. The refractive index and extinction coefficient of the Mn-doped HgO films are also reported. The refractive index dispersion n(λ) is analyzed by single-effective-oscillator dispersion model proposed by the Wemple–DiDomenico (WDD). The oscillator parameters were estimated. The obtained dispersion values are suitable for the design of optoelectronic devices. 相似文献
103.
Noresah Said Hasrinah Hasbullah Muhammad Nidzhom Zainol Abidin Ahmad Fauzi Ismail Pei Sean Goh Mohd Hafiz Dzarfan Othman Siti Hamimah Sheikh Abdul Kadir Fatmawati Kamal Mohd Sohaimi Abdullah Be Cheer Ng 《应用聚合物科学杂志》2019,136(21):47502
Protein existence in wastewater is an important issue in wastewater management because proteins are generally present as contaminants and foulants. Hence, in this study, we focused on designing a polysulfone (PSf) hollow-fiber membrane embedded with hydrophilic iron oxide nanoparticles (IONPs) for protein purification by means of ultrafiltration. Before membrane fabrication, the dispersion stability of the IONPs was enhanced by the addition of a stabilizer, namely, citric acid (CA). Next, PSf–IONP–CA nanocomposite hollow-fiber membranes were prepared via a dry–wet spinning process and then characterized in terms of their hydrophilicity and morphology. Ultrafiltration and adsorption experiments were then conducted with bovine serum albumin as a model protein. The results that an IONP/CA weight ratio of 1:20 contributed to the most stable IONP dispersion. It was also revealed that the membrane incorporated with IONP–CA at a weight ratio of 1:20 exhibited the highest pure water permeability (58.6 L m−2 h−1 bar−1) and protein rejection (98.5%) while maintaining a low protein adsorption (3.3 μg/cm2). The addition of well-dispersed IONPs enhanced the separation features of the PSf hollow-fiber membrane for protein purification. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47502. 相似文献
104.
Simulation results for continuous vacuum evaporation crystallization obtained by Aspen Plus and experimental results for semi‐batch vacuum evaporation crystallization are presented. In the crystallization experiments, the fixed heat duty was used to compare the water evaporation rates and crystal properties obtained at different pressures. The solution selected was aqueous glycine. It has the ability to form a number of different crystalline polymorphs, which allows it to exhibit a variety of different physical properties while maintaining its chemical properties. X‐ray diffraction results demonstrated that mainly the γ‐crystal form is produced under the conditions applied in vacuum evaporation crystallization. 相似文献
105.
106.
Matsagopane Gaamangwe Olakanmi Eyitayo Olatunde Botes Annelize Kutua Said 《JOM Journal of the Minerals, Metals and Materials Society》2019,71(5):1840-1857
JOM - Documentation on the correct process and component requirements for setting up efficient aluminum powder production systems capable of manufacturing powder that meets the requirements for the... 相似文献
107.
This work concerns the steady‐state and dynamic analysis of misaligned compliant journal bearings considering the effects of couple stresses arising from the lubricant blended with polymer additives. Based on the Stokes micro‐continuum theory, a modified form of the Reynolds equation is derived. The displacement field at the fluid film–bearing liner interface due to pressure forces is determined using the elastic thin liner model. The effects of the misalignment and the couple stress parameters on static and dynamic performances such as pressure distribution, load‐carrying capacity, power loss, side leakage flow, misalignment moment, critical mass and whirl frequency are presented and discussed. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
108.
The effects of two biodegradable corrosion inhibitors derived from vanillin and aminophenol (Meta: VPAP and Para: VOAP) on the corrosion of carbon steel in 1 M HCl solution were examined. The efficiency of these inhibitors on carbon steel corrosion increased by increasing the concentration and decreased by increasing the temperature. The inhibitors adsorbed on carbon steel physically and obeyed the Langmuir isotherm. The potentiodynamic measurements showed mixed-type inhibitor. The geometry of the inhibitors showed that VPAP has slightly higher efficiency in corrosion inhibition than VOAP. The inhibitors showed good biodegradability in the environment within 28 days. 相似文献
109.
Said Mohamed Elhadi Mezhoud Bilel Bouraiou Abdelmalek Chibani Aissa 《Protection of Metals and Physical Chemistry of Surfaces》2016,52(4):731-736
The 1-methylquinolinium iodide (I) Qui+, I– and 2-methylisoquinolinium iodide isoQui+, I– were investigated as a corrosion inhibitors for mild steel in sulfuric acid using electrochemical impedance spectroscopy and potentiodynamic polarization techniques. The results indicated that the corrosion inhibition efficiency and extent of surface coverage were increased with increase in inhibitors concentrations. Polarization curves revealed that both inhibitors acted as a mixed-type inhibitor. The thermodynamic parameters were evaluated for corrosion inhibition process. The adsorption of both inhibitors on mild steel surface obeyed Langmuir adsorption isotherm. 相似文献
110.
H. Babel J. Gibson M. Tarkanian C. Parrish M. Prietto A. Ordonez-Chu H. Haberl J. Kabisch R. Clark J. Ogren O.S. Es Said 《Journal of Materials Engineering and Performance》2007,16(5):584-591
The purpose of this study was to determine the acceptability of nonpenetrating, key-locked inserts in 2099 aluminum-lithium.
The tests conducted to make this assessment were: (1) microscopic examination for thread damage and delaminations after key
installation, (2) pull-out load at 21 °C (70 °F) and −179 °C (−290 °F), and (3) mechanical cycling tests at room temperature
and −179 °C (−290 °F). The test results indicated that for the three sizes evaluated, key-locked inserts in 2099-T6 and 2099-T8
were acceptable and although delaminations did occur on some T6 temper specimens, it was only as a failure mode at ultimate
load and such behavior was judged to be acceptable. 相似文献