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991.
992.
Shalaby Mohamed Shokair Mona Messiha Nagy Wadie 《Wireless Personal Communications》2019,109(3):1955-1970
Wireless Personal Communications - Localization in wireless sensor networks (WSNs) is a necessity as there is a vital need to have location information combined with the measured quantities. The... 相似文献
993.
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
994.
Mohamed R. Rizk Muhammad G. Abd El-Moghny 《International Journal of Hydrogen Energy》2021,46(1):645-655
We report on glycerol electro-oxidation in alkaline medium at macroporous Ni electrodes decorated with Cu particles. Macroporous Ni film is electrodeposited, using hydrogen bubbles as dynamic templates, atop of a Cu substrate. This film shows good electrocatalytic activity towards glycerol oxidation reaction (GOR). The Ni film is further decorated with Cu via spontaneous deposition from CuSO4 solution. This is done to enhance the catalytic activity of the film towards GOR. The morphology of the Cu-decorated Ni film is controlled using various additives such as KCl and (NH4)2SO4 which are added to the Cu deposition bath. The as-prepared Cu-decorated Ni films are characterized by electrochemical measurements, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). It is found that these additives have tremendous effects on the morphology and the electrocatalytic activity of the decorating Cu particles.The decorated Ni foam showed superior electrocatalytic activity towards the GOR, as confirmed by the negative shift in the onset oxidation potential (ca. 100 mV) together with an increase in oxidation current that is up to 1.5-fold during the cyclic voltammetry (CV) measurements, compared to the undecorated Ni foam. 相似文献
995.
We consider a two-sided sequence of bounded operators in a Banach space which are not necessarily injective and satisfy two properties (SVG) and (FI). The singular value gap (SVG) property says that two successive singular values of the cocycle at some index d admit a uniform exponential gap; the fast invertibility (FI) property says that the cocycle is uniformly invertible on the fastest d-dimensional direction. We prove the existence of a uniform equivariant splitting of the Banach space into a fast space of dimension d and a slow space of codimension d. We compute an explicit constant lower bound on the angle between these two spaces using solely the constants defining the properties (SVG) and (FI). We extend the results obtained by Bochi and Gourmelon in the finite-dimensional case for bijective operators and the results obtained by Blumenthal and Morris in the infinite dimensional case for injective norm-continuous cocycles, in the direction that the operators are not required to be globally injective, that no dynamical system is involved and no compactness of the underlying system or smoothness of the cocycle is required. Moreover we give quantitative estimates of the angle between the fast and slow spaces that are new even in the case of finite-dimensional bijective operators in Hilbert spaces. 相似文献
996.
997.
Hendawi Abdeltawab Gupta Jayant Liu Jiayi Teredesai Ankur Ramakrishnan Naveen Shah Mohak El-Sappagh Shaker Kwak Kyung-Sup Ali Mohamed 《The Journal of supercomputing》2019,75(12):8207-8230
The Journal of Supercomputing - In the current era of the Internet of Things (IoT), massive number of sensors are used in our daily lives. Sensors are everywhere around us. They exist in our homes,... 相似文献
998.
The purpose of this present study is to monitor the failure modes of pure resin and single layer of adhesively bonded lap joints using acoustic emission (AE) technique under tensile loading. Parametric analysis is performed using AE count rate, cumulative counts, time, frequency, amplitude and duration on the AE data obtained during the tensile test of adhesively bonded lap joints. After preliminary investigations in the parametric analysis, it was seen that AE amplitude parameter changes with the different AE events, thus failure modes were characterized using frequency analysis. Fast fourier transform (FFT) analysis has been proposed to identify the importance of peak frequency content of each failure mode corresponding to the AE hits using frequency FFT analysis. Short time fast fourier transform resulting frequency is correlated with FFT analysis of AE data, to find the peak frequency ranges for each of the failure modes. Scanning electron microscope as complementary, post-test inspection method is used to find microscopic evidence for the assumed assignment of failure modes. 相似文献
999.
Shahira Said Aly Tsuyoshi Imai Mohamed Salah Hassouna Diem-Mai Kim Nguyen Takaya Higuchi Ariyo Kanno Koichi Yamamoto Rinji Akada Masahiko Sekine 《International Journal of Hydrogen Energy》2018,43(10):5300-5313
The ability of Clostridium butyricum RAK25832 to use casamino acids as a nitrogen source was investigated. Strain RAK25832 showed the capacity to utilize different types of carbon sources. With glucose as a carbon source (10 g/L), the preferred final concentration of casamino acids was 26.67 g/L, with a cumulative hydrogen production, production rate, and yield of 2505 mL H2/L, 160 mL/h, and 1.81 mol H2/mol glucose, respectively. Eighteen metal elements were screened to identify the most important metals for biohydrogen production, and four elements were optimized. The optimal medium composition was MgCl2·6H2O (0.1 g/L), K2HPO4·3H2O (6.67 g/L), NaHCO3 (2.6 g/L), and FeCl2·4H2O (0.002 g/L). Vitamin supplementation of the medium showed no significant effect on hydrogen production. Under the optimized conditions, cumulative hydrogen production reached 3074 mL H2/L. This is the first study to demonstrate the use of casamino acids as a nitrogen source by C. butyricum. 相似文献
1000.
Abdelhedi Mohamed Mnif Thameur Abbes Chedly 《Russian Journal of Nondestructive Testing》2018,54(5):345-355
This paper discusses the ability of ultrasonic wave velocity to evaluate some physical parameters within mortar. The behavior of ultrasonic pulse velocity within mortar subjected to incremetal stress was also studied. For experimentation, we carried out ultrasonic measurements on mortar samples before and during uniaxial compressive strength, perpendicularly to the stress direction. The water/cement ratios were varied in order to contribute certain specific characteristics. A set of expressions was obtained linking the initial velocities of longitudinal ultrasonic waves with compressive strength, density, porosity and load at elastic limit.The evolution of ultrasonic velocity through mortar samples under continuous incremental uniaxial stress were also investigated. The results illustrated the behavior of ultrasonic pulse velocity as a function of the applied stress. It was observed that velocity did not decrease under initial loading and until about 70% of the ultimate stress, where sudden decrease occurred, followed by the failure of the material. 相似文献