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排序方式: 共有558条查询结果,搜索用时 171 毫秒
81.
Ahmed Youssef Al-Faraj Furat Scholz Miklas Soliman Akram 《Water Resources Management》2019,33(7):2485-2500
Water Resources Management - The aim of this article is to determine how human interventions in upstream countries coupled with drought events are affecting the flow regime of downstream countries... 相似文献
82.
AbstractDiazotized sulfadiazine derivative (1) was coupled with some nitrogen heterocyclic namely (thiazolone derivatives 2a–c, thiazole derivatives 4a–c and barbituric acid derivatives 6a,b) to give the corresponding azo compounds 3a–c, 5a–c and 7a,b in good yields. The newly synthesized azo benzene sulfonamide dyes were recorded their UV visible spectra in the region 200–600?nm in four different solvents and discussed the effect of solvents, substituent and effect of acid and base on the absorption values of these dyes. 相似文献
83.
Magdy Germein Harb Mohamed E. Elshaer A. M. Saad Laila Ebrahim Shaker Soliman Moataz 《JOM Journal of the Minerals, Metals and Materials Society》2019,71(6):1944-1951
JOM - Nanofibers were prepared from a poly(acrylonitrile-co-vinyl acetate) [P(AN-co-VAC)]/polyvinylidene fluoride (PVDF) blend and used as a quasi-solid (QS) electrolyte for dye-sensitized solar... 相似文献
84.
85.
Nancy Soliman Gilles Gasser Christophe M. Thomas 《Advanced materials (Deerfield Beach, Fla.)》2020,32(47):2003294
Ru(II) polypyridyl complexes are compounds of great interest in cancer therapy due to their unique photophysical, photochemical, and biological properties. For effective treatment, they must be able to penetrate tumor cells effectively and selectively. The development of nanoscale carriers capable of delivering Ru(II) polypyridyl complexes has the potential to passively or selectively enhance their cellular uptake in tumor cells. Many different strategies have been explored to incorporate Ru(II) polypyridyl complexes into a variety of nanosized constructs, ranging from organic to inorganic materials. Herein, recent developments in nanomaterials loaded with Ru(II) polypyridyl complexes are highlighted. Their rational design, preparation, and physicochemical properties are described, and their potential applications in cancer therapy are eventually discussed. 相似文献
86.
E. M. Abdel Bary Yaser A. Soliman Ahmed Fekri 《The International journal of environmental studies》2018,75(5):750-762
Novel membranes consisting of polyvinyl alcohol (PVA), cellulose nanocrystals (CNCs) originated from Rice Husk (RH), Glutaraldehyde (GLA) and Glycerine (G) were manufactured by the compression moulding process. Rice husk is a new source to isolate pure cellulose nanocrystals via mechanical and chemical treatment. The biodegradability of the membranes has been evaluated using UV accelerated weathering as well as a soil burial test. The morphology of membranes (PVA/RH-CNCs) was characterized by using the Scanning Electron Microscope (SEM). The chemical structure of the membranes (PVA/RH-CNCs) was characterised by Fourier-Transformation Infrared (FTIR) spectroscopy as well as wide-angle X-ray diffraction. The mechanical properties of the membranes were evaluated using standard techniques. Swelling and weight loss resulting from biodegradation were also evaluated. The results showed that the developed transient membranes can be used as food packaging bags owing to biodegradability (weight loss) under irradiation and during soil burial. 相似文献
87.
The wear behaviour of Al-4% Cu alloy and its composite containing-type alumina fibres has been studied at roomtemperature and at 150°C, using a standard pin-on-ringtribometer. The results show higher wear resistance and a lowercoefficient of friction for the composite material as comparedwith the matrix alloy. Three wear mechanisms of the matrix alloytested at room temperature were observed: oxidation-induceddelamination, seizure and subsequent wear due to surfacemelting. At 150°C, however, the matrix wear is due toseizure and melting. In the case of the composite material,different wear mechanisms were found: at low loads, oxidation-induced delamination was predominant, changing to high-strain-induced delamination at higher loads up to 80 N; at high loads(beyond 120 N) sub-surface delamination was the prevailingmechanism. 相似文献
88.
Gerges M. Salama Alshimaa H. Ismail Tarek Abed Soliman Hesham F.A. Hamed Nirmeen A. El‐Bahnasawy 《International Journal of Communication Systems》2020,33(12)
In 5G cloud computing, the most notable and considered design issues are the energy efficiency and delay. The majority of the recent studies were dedicated to optimizing the delay issue by leveraging the edge computing concept, while other studies directed its efforts towards realizing a green cloud by minimizing the energy consumption in the cloud. Active queue management‐based green cloud model (AGCM) as one of the recent green cloud models reduced the delay and energy consumption while maintaining a reliable throughput. Multiaccess edge computing (MEC) was established as a model for the edge computing concept and achieved remarkable enhancement to the delay issue. In this paper, we present a handoff scenario between the two cloud models, AGCM and MEC, to acquire the potential gain of such collaboration and investigate its impact on the cloud fundamental constraints; energy consumption, delay, and throughput. We examined our proposed model with simulation showing great enhancement for the delay, energy consumption, and throughput over either model when employed separately. 相似文献
89.
Ebtesam E. Ateia Galila Abdelatif Fatma S. Soliman 《Journal of Materials Science: Materials in Electronics》2017,28(8):5846-5851
Calcium nano ferrite with composition CaGdxEryFe2?x?yO4 (x?=?y?=?0.0, x?=?0.025, y?=?0.05) was prepared by citrate gel auto combustion method. The prepared samples showed orthorhombic phase structure and the crystallite sizes were found in the range of 32.1–35.3 nm. Detailed observation via the Field Emission Scanning Electron Microscopy (FESEM) showed that the calcium ferrite nano-particles were spherical and capsule like formation shape. The hysteresis loop confirms the magnetic behavior of the investigated samples, which is then discussed on the basis of super exchange interactions. Magnetic parameters such as saturation magnetization, coercivity, and retentivity were obtained. Greater than six-fold increase in coercivity (≈2085 Oe) was observed in calcium nanoferrites compared to the doped samples (≈360 Oe). The CaFe2O4-type structure includes edge- and corner sharing BO6 octahedral, constituting a very unique network similar to perovskite-related nanoparticles. This structural network leads to an improvement in the physical properties of the investigated samples. Great efforts have been made to synthesize pure nanoferrite samples without any secondary phases even after the substitution of low soluble rare earth ions. Special attention should be given to calcium ferrite nanoparticles which are suitable candidates to be used in the manufacturing of bone-like scaffolds, hyperthermia treatment of cancer and biological activity. 相似文献
90.
Naira Elazab Shaker El-Sappagh Ahmed Atwan Hassan Soliman Mohammed Elmogy Louai Alarabi Nagham Mekky 《计算机、材料和连续体(英文)》2021,67(2):1915-1926
Realism rendering methods of outdoor augmented reality (AR) is an interesting topic. Realism items in outdoor AR need advanced impacts like shadows, sunshine, and relations between unreal items. A few realistic rendering approaches were built to overcome this issue. Several of these approaches are not dealt with real-time rendering. However, the issue remains an active research topic, especially in outdoor rendering. This paper introduces a new approach to accomplish reality real-time outdoor rendering by considering the relation between items in AR regarding shadows in any place during daylight. The proposed method includes three principal stages that cover various outdoor AR rendering challenges. First, real shadow recognition was generated considering the sun’s location and the intensity of the shadow. The second step involves real shadow protection. Finally, we introduced a shadow production algorithm technique and shades through its impacts on unreal items in the AR. The selected approach’s target is providing a fast shadow recognition technique without affecting the system’s accuracy. It achieved an average accuracy of 95.1% and an area under the curve (AUC) of 92.5%. The outputs demonstrated that the proposed approach had enhanced the reality of outside AR rendering. The results of the proposed method outperformed other state-of-the-art rendering shadow techniques’ outcomes. 相似文献