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排序方式: 共有432条查询结果,搜索用时 15 毫秒
331.
Huma Bader Ul Ain Nazir Ahmad Ali Imran Bushra Niaz Muhammad Afzaal 《International Journal of Food Properties》2018,21(1):1463-1480
Cereals have captured global importance owing to the presence of bioactive moieties in cell wall. Numerous components have been considered but non-starch polysaccharides (NSP) of cereals cell wall are of prime concern. In this comprehensive review, the basic aim is to elaborate the functional and nutritional importance of cereals cell wall with special reference to NSP. Among bioactive components of cell wall, NSP, such as arabinoxylans, ß-glucans, and arabinogalactans of wheat and barley, have gained much importance. Moreover, literature revealed that NSP have greater role as prebiotic, immunomodulator, antioxidant, anti-diabetic, and cardio-protector as well as major food applications. 相似文献
332.
Chandrani Pramanik Tariq Jamil Jacob R. Gissinger Darice Guittet Pedro J. Arias‐Monje Satish Kumar Hendrik Heinz 《Advanced functional materials》2019,29(50)
Polyacrylonitrile (PAN) is among the most promising precursor polymers to produce strong and lightweight carbon fiber. Conformations in solution and the extent of binding to carbon nanotubes (CNTs) are critical during gel spinning and for alignment of graphitic layers upon carbonization. Here, quantitative insights into these processes are reported using molecular dynamics simulations at the atomic scale including virtual π electrons and comparisons to experimental data. Common solvents for fiber spinning induce significant differences in PAN conformation in dilute solutions at 25 °C with persistence lengths between 0.5 and 2 nm. Variations in conformation become smaller at 75 °C, in the presence of CNTs, and at higher PAN concentration. “Aging” of PAN conformations in dimethylformamide and dimethylsulfoxide at higher temperature is explained and a correlation between extended polymer conformations and increased binding to CNTs is identified in dilute solutions. PAN is overall barely attracted to CNTs under common solution conditions and enters significant surface contact only at higher concentration as solvent is physically removed. The impact of temperature is small, whereby binding increases at lower temperatures. The results provide guidance to control interactions of polymers with CNTs to induce distinct conformations and specific binding at the early stages of assembly. 相似文献
333.
A. A. Atta H. H. Wahba Ali. A. Alkathiri Waly A. L. Al-hasni Bushra Ahmed E. M. 《Glass Physics and Chemistry》2022,48(3):187-201
Glass Physics and Chemistry - Binary oxide glass system of the composition (100 – x)B2O3?xPbSO4 [0 ≤ x ≤ 40] is prepared by the press-quenching technique. The X-ray... 相似文献
334.
Ahmed A. Morgan Khalid M. Jamil Khayyat 《International Transactions in Operational Research》2022,29(1):259-300
The proper allocation of facilities within Islamic holy places is barely studied. These places annually witness millions of pilgrims and guests. The number of people during pilgrimage has been growing recently and is expected to grow further in the future. Different facilities should be optimally allocated to properly serve this large number of people and efficiently respond to their requests. In this paper, we target the problem of optimally allocating facilities within the largest Islamic holy place, Arafat. We evaluate the current allocation with respect to distance, coverage, and cover inequality metrics. Average-case and worst-case values of the three metrics are considered for evaluation. Results show that the current allocation strategy is far from being optimal. For the three considered metrics, we use crowdedness-based techniques to allocate facilities within the area of Arafat. Optimal allocations are first obtained by solving integer programming (IP) models. Thereafter, two widely used metaheuristics, genetic algorithms (GA) and simulated annealing, are experimented and evaluated. Results show that the optimal solution could be easily obtained for coverage and cover inequality metrics. For the distance metric, the computation time of the IP technique is large and GA appears as a good candidate to balance between computation time and solution quality. Finally, we study allocating facilities from a multiobjective perspective. Both scalar-weighted formulation and nondominated sorting genetic algorithm II techniques are considered. Results show that the latter technique outperforms the former technique in the number of generated Pareto-optimal allocations as well as the quality of these allocations. 相似文献
335.
Nosheen Feroze Bushra Arshad Muhammad Younas Muhammad Irfan Afridi Saddam Saqib Asma Ayaz 《Microscopy research and technique》2020,83(1):72-80
Nanoparticles as biomedicine has made a crucial role in health biotechnology. Different transition metals in various forms playing role in nanotechnological advances and biological applications. Silver as one of the nontoxic, safe inorganic antibacterial agents and can serve as replacement of antibiotics. Present research is based on biogenic synthesis of silver nanoparticles (Ag‐NPs) as potential antibiotics from fungal metabolites of Penicillium oxalicum. We used different analytical techniques X‐ray diffraction (XRD) and scanning electron microscopy (SEM) for characterization of biosynthesized silver nanoparticles. Furthermore, the antibacterial activity of biosynthesized silver nanoparticles was checked against Staphylococcus aureus, S. dysenteriae, and Salmonella typhi by using well diffusion method and UV visible spectrophotometer. Maximum zone of inhibition recorded against S. aureus, Shigella dysenteriae was 17.5 ± 0.5 mm (mm) for both species and 18.3 ± 0.60 mm for Salmonella typhi. The biosynthesized silver nanoparticles of P. oxalicum showed excellent antibacterial activity. It was concluded from our results that biosynthesized silver nanoparticles have significant potential and might be useful for a wide range of biological applications such as bactericidal agent against resistant bacteria, preventing infections, healing wounds, and anti‐inflammation. 相似文献
336.
337.
Muhammad Faisal Jamil Emre Biçer Begüm Yarar Kaplan Selmiye Alkan Gürsel 《International Journal of Hydrogen Energy》2021,46(7):5653-5663
High Pt loading has better tradeoff in polymer electrolyte membrane fuel cell (PEMFC) in terms of improved performance and operational longevity. But, to employ low amounts of Pt electrocatalysts via an alternative carbon-based support and utilization technique is vital. This study presents the use of a one-step novel technique, an electrophoretic deposition (EPD) method, through which reduced graphene oxide (rGO) supported Pt nanoparticles have been directly fabricated onto carbon paper to form electrodes for PEMFC. Our process involves simultaneous synthesis and deposition of Pt-reduced GO nanocomposites onto oxygen plasma pre-treated carbon paper in an organo-aqueous media at various deposition time. Through this technique, homogenously distributed Pt nanoparticles ranging from 5 to 6 nm in size on graphene support were successfully synthesized to form catalyst layer on carbon paper. The characteristics of fabricated electrodes were investigated ex-situ by Raman spectroscopy, FE-SEM, XPS, ICP, FIB, TEM. Furthermore, catalytic activity towards hydrogen oxidation reaction was evaluated via CV measurements and fuel cell performance tests were also conducted. The highest ECSA value of 27.4 m2g-1 and the Pt utilization efficiency of 1.48 kW/gPt?1 were achieved at an optimized Pt loading of 0.129 mg cm?2. A maximum power density of 280 mW cm?2 was obtained with increasing EPD time and Pt precursor concentration at the same time. The achieved results are attributed to the dispersion of Pt nanoparticles on rGO nanosheets displaying synergetic performance as catalyst necessary for PEMFCs, thanks to the EPD technique's viability, ease in handling, and reproducibility in the synthesis route. In the previous studies on Pt/GO based fuel cell electrodes by EPD, on one hand, Pt NPs were synthesized on GO by chemical methods first and electrodes were fabricated by a subsequent EPD. On the other hand, the fuel cell performances of those electrodes have been rarely shown. To the best of our knowledge, this is the first time in literature not only about the use of EPD technique for the fabrication of fuel cell electrodes in one-step but also the evaluation of fuel cell performance of the electrodes fabricated by EPD. 相似文献
338.
Joyce Robin Panwar Deepak Kumar Shakil Moh. Varghese Soney Akhtar Jamil 《Microsystem Technologies》2018,24(5):2277-2285
Microsystem Technologies - Substrate masking plays an important role in wet chemical etching process, however; coating a cost effective masking material with higher stability in the harsh chemical... 相似文献
339.
Sabah Said Razouki Bushra M. Salem 《International Journal of Pavement Engineering》2017,18(2):108-118
A laboratory investigation and analysis on the resilient modulus of gypsum-rich roadbed sand with a gypsum content of 38.8%, subjected to cyclic soaking and drying with a cycle length of 14 days, is presented and discussed. Eleven pairs of California bearing ratio (CBR) soil specimens were prepared for determining the resilient modulus using the wave propagation technique. After the application of this technique, the CBR load–penetration test was performed on each specimen to make use of the corresponding curve for determining the resilient modulus too. The wave propagation resilient modulus results are generally in good agreement with those based on CBR full load–penetration curve. The paper reveals that the cyclic soaking and drying process converges to an equilibrium state after the fifth cycle resulting in a resilient modulus which is much less than that for the common four days of soaking or that obtained from published correlation studies. 相似文献
340.
Jampana B.R. Melton A.G. Jamil M. Faleev N.N. Opila R.L. Ferguson I.T. Honsberg C.B. 《Electron Device Letters, IEEE》2010,31(1):32-34
The design of coherently strained InGaN epilayers for use in InGaN p-n junction solar cells is presented in this letter. The X-ray diffraction of the epitaxially grown device structure indicates two InGaN epilayers with indium compositions of 14.8% and 16.8%, which are confirmed by photoluminescence peaks observed at 2.72 and 2.67 eV, respectively. An open-circuit voltage of 1.73 V and a short-circuit current density of 0.91 mA/cm2 are observed under concentrated AM 0 illumination from the fabricated solar cell. The photovoltaic response from the InGaN p-n junction is confirmed by using an ultraviolet filter. The solar cell performance is shown to be related to the crystalline defects in the device structure. 相似文献