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101.
Reza Davarnejad Meysam Sabzehei Fatemeh Parvizi Saeid Heidari Asma Rashidi 《化学工程与技术》2019,42(12):2717-2725
Due to its low viscosity, soybean oil is commonly used as edible oil. Its production is accompanied by a large amount of wastewater containing hazardous materials like phenolic compounds. In this study, the electro‐Fenton process with response surface methodology was applied for oil removal from wastewater of soybean oil plants. Five independent variables, including reaction time, pH, current density, molar ratio of H2O2 to Fe2+, and volume fraction of H2O2 to wastewater, were investigated for their effects on oil removal. The significant independent variables were optimized by the Box‐Behnken design. The optimum conditions were statistically obtained, and the results were confirmed by experiment. 92.66 % oil removal were experimentally found for the optimum conditions. 相似文献
102.
Amina Nemchi Ahmed Bouzidane Marc Thomas Asma Abed 《Tribology - Materials, Surfaces & Interfaces》2018,12(2):59-70
This paper presents a theoretical study of the effects of Poiseuille Reynolds number and eccentricity ratio on the performance of four-pad hydrostatic squeeze film dampers. The finite difference method has been used to solve Reynolds equation based on Constantinescu’s turbulent lubrication theory. The numerical results obtained are analysed and compared between three and four-lobe hybrid journal bearings. The computed results indicate that the performance of a hydrostatic squeeze film damper loaded between pads is significantly influenced by the flow regimes. The results presented in this work can be useful to the bearing designers. 相似文献
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Muhammad Maqbool Qaisar Nawaz Muhammad Atiq Ur Rehman Mark Cresswell Phil Jackson Katrin Hurle Rainer Detsch Wolfgang H. Goldmann Asma Tufail Shah Aldo R. Boccaccini 《International journal of molecular sciences》2021,22(8)
In this study, as a measure to enhance the antimicrobial activity of biomaterials, the selenium ions have been substituted into hydroxyapatite (HA) at different concentration levels. To balance the potential cytotoxic effects of selenite ions (SeO32−) in HA, strontium (Sr2+) was co-substituted at the same concentration. Selenium and strontium-substituted hydroxyapatites (Se-Sr-HA) at equal molar ratios of x Se/(Se + P) and x Sr/(Sr + Ca) at (x = 0, 0.01, 0.03, 0.05, 0.1, and 0.2) were synthesized via the wet precipitation route and sintered at 900 °C. The effect of the two-ion concentration on morphology, surface charge, composition, antibacterial ability, and cell viability were studied. X-ray diffraction verified the phase purity and confirmed the substitution of selenium and strontium ions. Acellular in vitro bioactivity tests revealed that Se-Sr-HA was highly bioactive compared to pure HA. Se-Sr-HA samples showed excellent antibacterial activity against both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus carnosus) bacterial strains. In vitro cell–material interaction, using human osteosarcoma cells MG-63 studied by WST-8 assay, showed that Se-HA has a cytotoxic effect; however, the co-substitution of strontium in Se-HA offsets the negative impact of selenium and enhanced the biological properties of HA. Hence, the prepared samples are a suitable choice for antibacterial coatings and bone filler applications. 相似文献
105.
Saraj Bahadur Mushtaq Ahmad Muhammad Zafar Saba Gul Asma Ayaz Shomaila Ashfaq Saima Rubab Muhammad Shuaib Shakil Ahmad 《Microscopy research and technique》2020,83(4):345-353
Recent field exploration and collections has led to the findings of several new species in Pakistan. Here we reported two new species Ajuga reptance L and Sphagneticola trilobata (L.) Prusk for the first time in Pakistan flora as these species were neither listed in any other literature nor identified before in Pakistan. These species were found as a result of taxonomic studies performed in the year 2019 in District Rawalpindi and Islamabad, Pakistan. Microscopic techniques were used for the confirmation of foliar epidermal and pollen micromorphological features. Detailed study (morphological, palynological, and foliar epidermal) was provided for the correct identification and delimitation of the species using both light and scanning electron microscopy. Morphological results were compared with the flora of Taiwan and China. 相似文献
106.
Rahmoun Smail Mehiaoui-Hamitou Asma Borde Etienne Pautet Laurent Soubiran Elie 《Software and Systems Modeling》2019,18(1):107-127
Software and Systems Modeling - Designing software architectures and optimizing them based on extra-functional properties (EFPs) require to identify appropriate design decisions and to apply them... 相似文献
107.
Asma Sofyane Mohammed Lahcini Abdellatif El Meziane Mehdi Khouloud Abdelmalek Dahchour Sylvain Caillol Mustapha Raihane 《Journal of the American Oil Chemists' Society》2020,97(7):751-763
In an effort to enhance the efficiency of fertilizer use and minimize their negative impact on the environment, a novel biomass-based, functional controlled-release fertilizer was used to improve nutrient use efficiency and increase crop production systems for more sustainable agriculture practices. Here, bio-based amino-oil (Priamine) mixtures were proposed as an outer coating with different layers for the control of phosphorus release from diammonium Phosphate (DAP). These hydrophobic coatings conferred excellent barrier properties and flexibility to coatings. The morphological characterization of the coated fertilizer was performed by scanning electronic microscopy (SEM), electronic diffraction X-ray (EDX) and mapping, and revealed the formation of a cohesive film and a good adhesion between DAP fertilizer and coating film. The release rate of nutrients (phosphate) in water was investigated by UV–Vis spectrophotometer. The effect of coating thickness was investigated on release time and diffusion coefficient of phosphor release in distilled water. Release time increased with the coating thickness. The diffusion coefficient of nutrient release decreased with the coating thickness. Compared with uncoated granule which is totally solubilized after less than 2 hours, the P release profiles of the coated granules reached the equilibrium stage approximately after 98 and 126 hours when the DAP is coated with only Priamine single-layer (1L) and double-layer (2L), respectively. Moreover, the strategy adopted has successfully provided a very slow release and long-term availability of nutrient sources with bio-based coating oil compared to uncoated fertilizer (DAP) and therefore exhibited promising application for sustainable development of modern agriculture and circular economic. 相似文献
108.
Wireless Personal Communications - Among metrics that highly affect video quality and quality of experience (QoE), we can cite the stalling and the visual quality caused by mobile network overhead.... 相似文献
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Tayyaba Najam Shumaila Ibraheem Muhammad Altaf Nazir Asma Shaheen Amir Waseem Muhammad Sufyan Javed Syed Shoaib Ahmad Shah Xingke Cai 《International Journal of Hydrogen Energy》2021,46(13):8864-8870
It's still an ongoing research challenge to explore non-precious metal-based catalysts for substituting precious metal catalysts during full water electrocatalysis. Herein, we reported the partially oxidized cobalt species in nitrogen-doped carbon nanotubes hierarchical structures to produce dual-functionality towards oxygen/hydrogen evolution reactions. The in situ transformation of carbon nanotubes and well-exposed metal-oxide contributes to mass diffusion and greater electrolyte-accessible surface area. The as-synthesized catalyst displays low overpotentials of 287 mV and 171 mV for oxygen and hydrogen evolution reactions at 10 mA cm?2 of current density with remarkable performance during long-term stability. Furthermore, when employed as cathode and anode, a respectable performance of 1.68 V demonstrated our catalyst as an efficient bifunctional material for conducting water-splitting operation. 相似文献
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Nisar Fatima Muhammad Bilal Tahir Asma Noor M. Sagir M. Suleman Tahir Hussein Alrobei Urooj Fatima Khurram Shahzad Arshid Mahmood Ali Shabbir Muhammad 《International Journal of Hydrogen Energy》2021,46(50):25413-25423
Recently, photocatalysis has received huge attention in order to overcome energy crisis worldwide. Many semiconductors, potential schemes and hierarchies have come to light during past few decades to fabricate efficient catalysts however, among all these methods heterostructures have taken the world by surprise. With the advancement in post-graphene 2D materials, van der Waals heterostructures have come to light exploring enhancement in photocatalysis. During a very short period a number of ZnO-based van der Waal heterostructures have taken the limelight in the field of photocatalysis. First principles calculations and DFT approach towards the heterostructures of GeC, GaN, WSe2, WS2 and other layered 2D materials unleased a series of properties and facts for the provision of enhanced catalysis. Reduction in bandgap of ZnO has also been observed which widens the pathways towards visible light irradiation. However, energy applications of zinc oxide are also fascinating feature as it can serve as a photoanode to replace TiO2. Whereas the famous hydrogen production, batteries and solar cells have also been fabricated by the use of this semiconductor. 相似文献