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111.
Abolfazl Shoja Mohamad Ali Adabi Masoud Ahmadnia Jamal Zamani 《Propellants, Explosives, Pyrotechnics》2014,39(4):574-579
In most blast loading structure analyses, it is assumed that the load acts uniformly on a target area. For the rationable design, it is useful to have a quantitative criterion to determine at which maximum distance the standoff can be placed to assume a uniform pressure distribution. Surprisingly, no standard criterion was found in the literature and the effect of blast wave clearing was not considered as well. In this paper, pressure histories applied on structures are calculated considering the non‐uniform loading characteristic as well as pressure relief from the edges. Additionally, the effects of various parameters on uniformity of impulse distribution are investigated. The results have shown that the effect of pressure relief on impulse uniformity is very important, especially when the blast wave is attenuated. This phenomenon leads an optimum distance at which impulse distribution is the most uniform. 相似文献
112.
Gillian R. Hayes Sen Hirano Gabriela Marcu Mohamad Monibi David H. Nguyen Michael Yeganyan 《Personal and Ubiquitous Computing》2010,14(7):663-680
Interventions to support children with autism often include the use of visual supports, which are cognitive tools to enable learning and the production of language. Although visual supports are effective in helping to diminish many of the challenges of autism, they are difficult and time-consuming to create, distribute, and use. In this paper, we present the results of a qualitative study focused on uncovering design guidelines for interactive visual supports that would address the many challenges inherent to current tools and practices. We present three prototype systems that address these design challenges with the use of large group displays, mobile personal devices, and personal recording technologies. We also describe the interventions associated with these prototypes along with the results from two focus group discussions around the interventions. We present further design guidance for visual supports and discuss tensions inherent to their design. 相似文献
113.
Juan Xie Yawen He Xian Li Ming Duan Junlei Tang Yingying Wang Mohamad Chamas Hu Wang 《Journal of Materials Science: Materials in Electronics》2017,28(20):14981-14987
Strontium titanate (STO) with shape of nanosheet, polyhedron and nanosphere is prepared by one-pot solvothermal method using ethanolamine (EA), diethanolamine (DA) and ethylene glycol (EG), respectively. Upon the different crystalline size and morphology of STO, effect of solvents on nucleation and growth is discussed. In this case, energy band and flat band potential of samples are measured by UV–Vis diffuser reflectance (DRS) and Mott-Schottky (MS). Results show narrow energy band (Eg) 2.68, 2.87 and 3.17 eV of as-synthesized pure STOs (EA-STO, DA-STO and EG-STO) compared with empirical STO. Simultaneously, valence band shows 0.55, 1.80 and 2.21 eV respectively. Rhodamine B (RhB) and methyle orange (MO) are selected as anionic and cationic target contaminants. Correlation of photodegradation performance and valence band is depicted. 相似文献
114.
115.
Ahmed Y. Musa Abu Bakar Mohamad Abdul Amir H. Kadhum Mohd Sobri Takriff Waleed Ahmoda 《Journal of Industrial and Engineering Chemistry》2012,18(1):551-555
Quantum chemical calculations were performed on ten thio compounds using semi-empirical method PM3 within program package of Material Studio 5.5. The effect of molecular structure on the corrosion inhibition efficiency was investigated using the quantum chemical calculations. The electronic properties such as highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO) energy levels, (LUMO–HOMO) energy gap, dipole moment (λ) and fraction of electron transfer (ΔN) were calculated and discussed. A relationship between the corrosion inhibition efficiency and several quantum parameters was established with coefficient correlation (R2) of 0.8894. 相似文献
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117.
Yannick Raoul des Essarts Mohamad Sabbah Arnaud Comte Laurent Soulère Yves Queneau Yves Dessaux Valérie Hélias Denis Faure 《International journal of molecular sciences》2013,14(10):19976-19986
Bacteria belonging to the Pectobacterium genus are the causative agents of the blackleg and soft-rot diseases that affect potato plants and tubers worldwide. In Pectobacterium, the expression of the virulence genes is controlled by quorum-sensing (QS) and N-acylhomoserine lactones (AHLs). In this work, we screened a chemical library of QS-inhibitors (QSIs) and AHL-analogs to find novel QSIs targeting the virulence of Pectobacterium. Four N,N′-bisalkylated imidazolium salts were identified as QSIs; they were active at the μM range. In potato tuber assays, two of them were able to decrease the severity of the symptoms provoked by P. atrosepticum. This work extends the range of the QSIs acting on the Pectobacterium-induced soft-rot disease. 相似文献
118.
Addition of low quantities of ytterbium to sol–gel prepared Ni/γ-Al2O3 catalysts has been shown to lead to significant increases in catalytic activity and long term stability in the catalytic conversion of CO2 and CH4 into syngas (H2 and CO). The role of ytterbium in these catalysts was investigated in this study through detailed investigations on the structure and composition of ytterbium promoted Ni/γ-Al2O3 catalysts using the following techniques: synchrotron X-ray diffraction, X-ray Photoemission Spectroscopy, Transmission Electron Microscopy, Scanning Electron Microscopy/Energy Dispersive X-ray analysis, Temperature Programmed Reduction techniques and N2 adsorption–desorption isotherms. The results obtained indicated that ytterbium, at small quantities (up to 2 wt%), interacted strongly with the support which in turn altered the interaction between nickel and the support (most notably it was found to completely inhibit the formation of NiAl2O4). This decreased interaction between Ni and the support also led to a higher quantity of Ni being present in the catalyst in the form of Ni. 相似文献
119.
120.
Nader Ghaffari-Nasab Mohamad Saeed Jabalameli Mir Bahador Aryanezhad Ahmad Makui 《The International Journal of Advanced Manufacturing Technology》2013,67(9-12):2007-2019
The location-routing problem (LRP) is a relatively new research area within location analysis that concerns simultaneously both the problems of location of facilities and routing of vehicles among the established facilities and the demand points. In this work, we address the capacitated LRP with probabilistic travel times, which may arise in many practical contexts in logistics and supply chain management, and present some bi-objective mathematical programming formulations to model the problem using different stochastic programming approaches. The first objective is to minimize the overall system-wide costs, while the second objective concerns minimization of the maximum delivery time to the customers. In all the cases, the deterministic equivalents of the stochastic models have been extracted. To solve the resulted models, a variable neighborhood descent-based heuristic is proposed and finally computational study is performed and numerical results are reported. 相似文献