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排序方式: 共有3161条查询结果,搜索用时 46 毫秒
91.
Khalid Almutairi Seyyed Shahabaddin Hosseini Dehshiri Seyyed Jalaladdin Hosseini Dehshiri Ali Mostafaeipour Alibek Issakhov Kuaanan Techato 《International Journal of Hydrogen Energy》2021,46(36):18795-18815
Increasing energy demand has led to a substantial growth in the use of wind energy across the world, which can be attributed to the low initial and running costs and rapid and easy deployment of this technology. The development of hydrogen from wind energy is an excellent way to store the excess wind power produced, as the produced hydrogen can be used not only as clean fuel but also as input for various industries. Considering the good wind potentials of Yazd province, the variety of industries that are active in this area, and the central location of this province in Iran, which gives it ample access to major transport routes and other industrial hubs, hydrogen production from wind power in this province could benefit not only this region but the entire country. Given these considerations, we conducted a technical, economic, and environmental assessment of the potential for wind power generation and hydrogen production in Yazd province. Overall, the assessments showed that the best locations for harvesting wind energy in this province are Bahabad and Halvan stations. For these two stations, it is recommended to use EWT DW 52-900 turbine to take advantage of its higher nominal capacity to achieve higher electricity and hydrogen output and emission reduction. For Abarkoh and Kerit stations, which have a low wind energy potential, it is recommended to use small turbines such as Eovent EVA120 H-Darrieus. Also, economic and technical assessments showed that it is not economically justified to harvest wind energy in Ardakan station. The results of ranking the stations with the Step-wise Weight Assessment Ratio Analysis (SWARA) and Evaluation based on Distance from Average Solution (EDAS) techniques showed that Bahabad station was introduced as the best place to produce hydrogen from wind energy. 相似文献
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93.
Bahareh Sarmadi Farhana Aminuddin Muhajir Hamid Nazamid Saari Azizah Abdul-Hamid Amin Ismail 《Food chemistry》2012
Fat, alkaloid and polyphenol contents of two clones of cocoa (UIT1 and PBC 140) were removed and the remaining powder was autolyzed at pH 3.5 and 5.2. Based on the results, autolysates of UIT produced at pH 3.5 exhibited the highest ability to inhibit α-amylase activity. However, no α-glucosidase inhibition activity was observed under the conditions specified. Autolysates produced under pH 3.5 caused the highest amount of insulin secretion. In streptozotocin-diabetic rats, all cocoa autolysates significantly decreased blood glucose at 4 h. To assure that the results from the assays were not due to the polyphenols of cocoa autolysates qualitative and quantitative tests were applied. According to their results cocoa autolysates were found to be free from polyphenols. Analysis of amino acid composition revealed that cocoa autolysates were abundant in hydrophobic amino acids. It can be suggested that besides other compounds of cocoa, its peptides and amino acids could contribute to its health benefits. 相似文献
94.
Mehdi Panji Hamid Koohsari Mohammad Adampira Hamid Alielahi Jafar Asgari Marnani 《岩石力学与岩土工程学报(英文版)》2016,(4):480-488
In this paper, stress behavior of shallow tunnels under simultaneous non-uniform surface traction and symmetric gravity loading was studied using a direct boundary element method(BEM). The existing fullplane elastostatic fundamental solutions to displacement and stress fields were used and implemented in a developed algorithm. The cross-section of the tunnel was considered in circular, square, and horseshoe shapes and the lateral coefficient of the domain was assumed as unit quantity. Double-node procedure of the BEM was applied at the corners to improve the model including sudden traction changes. The results showed that the method used was a powerful tool for modeling underground openings under various external as well as internal loads. Eccentric loads significantly influenced the stress pattern of the surrounding tunnel. The achievements can be practically used in completing and modifying regulations for stability investigation of shallow tunnels. 相似文献
95.
A numerical method for the generation of the microstructure of a binary aluminum copper alloy is presented. This method is based on the repeated addition of some basic grain shapes into a representative volume element. Depending of the orientation of adjacent grains, different type of grain boundaries can be formed. The primary and secondary phases are distinguishable in our model and have distinct properties, reflecting the heterogeneous nature of the microstructure. The digital microstructure was then transformed into a finite element model. Using the finite element software ABAQUS, the stress distribution inside our heterogeneous material model has been studied and its mechanical properties have been found. That also makes possible to study and to visualize the cracks generated during the loading of the material where the local stress was sufficiently high. As a result of these analyses, the elastic modulus of such a heterogeneous domain and the effect of crack formation on ductility were evaluated. 相似文献
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98.
M. Ebrahimi R. Raeisi Shahraki S. A. Seyyed Ebrahimi S. M. Masoudpanah 《Journal of Superconductivity and Novel Magnetism》2014,27(6):1587-1592
The influence of the precipitant and ferric concentration on the magnetic properties of coprecipitated zinc ferrite nanoparticles has been investigated. The nanoparticles were characterized using X-ray diffraction, scanning and transmission electron microscope, and vibrating sample magnetometer techniques. The results showed that the single-phase zinc ferrite with partially inverse spinel structures can be formed at high concentrations. The inversion coefficient calculated by the Rietveld method decreases with increasing of the concentrations, may be due to the crystal growth. The magnetic measurements exhibited that the coprecipitated zinc ferrite nanoparticles were superparamagnet and magnetization decreases with increasing of the concentrations through decreasing of inversion coefficient. 相似文献
99.
100.
Sachin Patil Yi Yang Tay Farzad Baratzadeh Hamid Lankarani 《Journal of Mechanical Science and Technology》2017,31(7):3225-3232
Ever increasing requirements regarding vehicle safety have led to rapid developments in various joining process. Among FSW widely used for Aluminum alloy welded structure of car body because of their remarkable performance in welding. For a better understanding of this performance, it is necessary to determine the behavior of butt weld in service conditions. In earlier phase of this study, thermo mechanical simulations and analysis are performed to understand the thermal behavior in the FSW weld zones. The developed models are correlated against published experimental results in terms of temperature profile of the weld zone. The objectives of the second part of this work is to develop and demonstrate an FE model of bumper and crash box assembly that would improve on the current modeling techniques for the mechanical response of welds in structural problems. 相似文献