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排序方式: 共有372条查询结果,搜索用时 140 毫秒
361.
362.
Mohammad Javad Goodarzi Majid Moradi Pedram Jalali Moein Abdolmohammadi Seyed Milad Hasheminejad 《The Structural Design of Tall and Special Buildings》2023,32(11-12):e2017
Fragility curves development in structures has always been a focus of research interest among structural and earthquake engineers for which the maximum story drift is usually considered as the engineering demand parameter (EDP) known as the conventional approach. This paper aims at calculating the fragility curves of a tall building with outrigger braced system by considering the plastic strain energy as the EDP and compare it with the conventional approach. In addition, the effect of optimizing the position of outriggers on the exceedance probability of the structure under near- and far-fault seismic loadings is investigated in this paper. Fragility curves of this structure in four performance levels including immediate occupancy (IO), life safety (LS), collapse prevention (CP), and instability is extracted based on the conventional method. The fragility curves for the aforementioned performance levels are also extracted based on the plastic strain energy and compared with the conventional approach. The results have demonstrated that optimizing the location of the bracing system would lower the exceedance probability of the structure. Moreover, the exceedance probability of the investigated building with outrigger braced system under far-fault records in various levels is more than that of near-fault records. It is also concluded that the conventional approach would lead to more conservative results compared with the energy approach. 相似文献
363.
Yi Lu Milad Kamkar Shasha Guo Xun Niu Zhangmin Wan Junhua Xu Xiaoya Su Yimin Fan Long Bai Orlando J. Rojas 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(39):2370315
Non-equilibrium multiphase systems are formed by mixing two immiscible nanoparticle dispersions, leading to bicontinuous emulsions that template cryogels with interconnected, tortuous channels. Herein, a renewable, rod-like biocolloid (chitin nanocrystals, ChNC) is used to kinetically arrest bicontinuous morphologies. Specifically, it is found that ChNC stabilizes intra-phase jammed bicontinuous systems at an ultra-low particle concentration (as low as 0.6 wt.%), leading to tailorable morphologies. The synergistic effects of ChNC high aspect ratio, intrinsic stiffness, and interparticle interactions produce hydrogelation and, upon drying, lead to open channels bearing dual characteristic sizes, suitably integrated into robust bicontinuous ultra-lightweight solids. Overall, it demonstrates the successful formation of ChNC-jammed bicontinuous emulsions and a facile emulsion templating route to synthesize chitin cryogels that form unique super-macroporous networks. 相似文献
364.
365.
Maleki Dastjerdi Sajad Arzani Milad 《Clean Technologies and Environmental Policy》2023,25(7):2213-2232
Clean Technologies and Environmental Policy - In this study, for the first time, an off-grid zero-energy building with hydrogen energy storage integrated with two hydrogen cars is simulated and... 相似文献
366.
Farajollahi Amirhamzeh Rostami Mohsen Feili Milad Ghaebi Hadi 《Clean Technologies and Environmental Policy》2023,25(5):1673-1698
Clean Technologies and Environmental Policy - Generally, a stand-alone flash-binary geothermal power plant loses most of its input energy, so its efficiency declines accordingly. Its overall... 相似文献
367.
Abbas Moghim Maisam Jalaly Sadegh Sadeghzadeh 《International Journal of Applied Ceramic Technology》2022,19(3):1669-1677
In the first stage of this work, the master nanocomposite of niobium carbide (NbC)–Cu (ceramic-based nanocomposite) was synthesized by a mechanically induced magnesiothermic combustion in the Nb2O5/CuO/Mg/C system. Ignition time in this system was recorded to be ∼28 min of milling. In the second stage, appropriate amounts of NbC–Cu nanocomposite powder were mixed with pure copper powder to prepare Cu-based nanocomposite with 0, 5, 10, 15, and 20 volume fraction of NbC. The final metal matrix nanocomposite powder was sintered by spark plasma sintering method. The density of nanocomposite specimens decreased with increasing the percentage of NbC nanoparticles, while the microhardness of specimens increased with increasing nano-NbC content. Regarding the tensile test, the sample Cu–10 vol.% NbC nanocomposite with a strength of 372 MPa (∼63% higher than that of nonreinforced copper) was the best composition, and the nanocomposite strength decreased at higher NbC concentrations, mostly due to the agglomeration and nonhomogeneous distribution of reinforcing nanoparticles. 相似文献
368.
Silicon - This article presents a new directional coupling between two transverse strip metal-insulator-metal (TS-MIM) waveguides on silicon-on-insulator (SOI) platform at 1.55 μm... 相似文献
369.
In this study, we investigate the use of asphaltene, a natural waste product that is inevitably formed during heavy oil processing, as a filler in polymer composites. The focus of this work is on the compatibility of various asphaltenes, featuring different polarities, with several polymers, including polypropylene (PP), polystyrene (PS), polymethyl methacrylate (PMMA), and polycarbonate (PC). The Hansen solubility parameters were plotted to predict the compatibility of polymers with different asphaltenes. Then, polymer composites were prepared by two common techniques: melt mixing and solution mixing. The dispersion state of the asphaltenes in each polymer was investigated by using imaging and rheological techniques. This work showed that the network structure of the asphaltenes and, thus, the final properties of the composites can be controlled by the polarity of asphaltenes, mixing technique, and melt viscosity of the polymer. For instance, more polar asphaltene (Asph P) produced smaller aggregates in PMMA, which has a higher polar solubility parameter than PP or PS. At 2.5 wt.% of asphaltene, Asph P showed 26% and 177% larger asphaltene agglomerates in PP and PS, respectively, than the less polar asphaltene (Asph Al). PS/asphaltene and PMMA/asphaltene composites prepared by the solution mixing method exhibited better dispersion compared to their melt-mixed counterparts. In melt-mixed composites, the dispersion quality of the asphaltene was better for polymers with higher melt viscosity. Thus, a careful choice of polymer, asphaltene, and preparation conditions can be used to tune the properties of asphaltene/polymer composites. 相似文献
370.
Hasan Naghizadeh Reza Nosouhi Seyed Adel Badiezadegan Milad Soleymani Amir Mohammad Azadi Noushin Azimy Hamidreza Azimy 《Advanced Engineering Materials》2023,25(12):2201918
This research aims to investigate the effect of adding copper oxide nanoparticles to the oil Gr-6004 base fluid and its concentration changes from 0.1% to 0.4% on the surface roughness of gudgeon pin and the thermal conductivity of the nanofluids during the superfinishing process. The main novelty of this investigation is analyzing the impact of utilizing CuO/oil Gr-6004 nanofluid on thermal conductivity of oil and surface quality of gudgeon pin during superfinishing process. Based on the results, adding nanoparticles to the oil Gr-6004 has significantly reduced the surface roughness. In addition, by increasing the concentration of nanoparticles to 0.4%, the surface roughness has decreased by 57% compared to oil Gr-6004. Also, by adding nanoparticles, the thermal conductivity of the nanofluids has increased to 19.5%. In addition, dispersing CuO nanoparticles into base fluid reduces oil temperature by 17.44%. 相似文献