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51.
Ali IZADI GHAHFEROKHI Masoud KASIRI-ASGARANI Kamran AMINI Mahdi RAFIEI Reza EBRAHIMI-KAHRIZSANGI 《中国有色金属学会会刊》2022,32(3):908-926
研究使用不同的中间层瞬时液相连接两种异种高温合金的适用性.在1100℃、不同时间下瞬时液相连接GTD-111/IN-718体系,研究BNi-2、BNi-3和BNi-9三种类型的中间层对该体系显微组织和力学性能的影响.采用场发射扫描电子显微镜和能量色散光谱技术,研究接头区域的成分变化和显微组织.结果表明,非热凝固区Ni3... 相似文献
52.
Mohammad Sabzi Masoud Babaahmadi Navid Samadi Gholam Reza Mahdavinia Mohsen Keramati Nasser Nikfarjam 《Polymer International》2017,66(5):665-671
Here strong electroactive shape memory nanocomposites were prepared by incorporating graphene nanoplatelets into poly(vinyl acetate) (PVAc ) through the simple solvent mixing method. TEM and XRD revealed that well exfoliated graphene nanoplatelets formed a continuous network throughout the matrix with a large amount of interconnectedness. Dynamic mechanical analysis showed that the inclusion of graphene significantly improves both glassy and rubbery moduli of the matrix. Furthermore, the prepared nanocomposites demonstrated a marked electrical conductivity up to 24.7 S m?1 and thereby surprisingly rapid electrical actuation behaviour exhibiting a 100% recovery ratio in 2.5 s. Moreover, PVAc and its nanocomposites displayed scratch self‐healing capability. This work demonstrates that the PVAc /graphene nanocomposites with high modulus and excellent electroactive shape memory performance can be a promising material in many applications such as sensors and fast deployable and actuating devices. © 2016 Society of Chemical Industry 相似文献
53.
54.
In this work, neat and modified nanodiamond (ND) particles were embedded into high-density polyethylene (HDPE) membranes to improve hydrophilicity and antifouling properties. The membranes were prepared via thermally induced phase separation (TIPS) method and used for pharmaceutical wastewater treatment in membrane bioreactors (MBR) system. To prevent the agglomeration of ND, it was modified using two methods: thermal carboxylation (ND-COOH) and grafting with polyethylene glycol (ND-PEG). Membranes with different concentration of ND-COOH and ND-PEG nanoparticles ranging from 0.00 to 1.00 wt % were prepared and characterized using a set of analyses including water contact angle, pure water flux, tensile strength, differential scanning calorimeter, field emission scanning electron microscopy, and energy dispersive X-ray spectroscopy. It was found that the optimum contents of ND-COOH and ND-PEG nanoparticles were 0.50 wt % and 0.75 wt %, respectively. The interfacial interaction between nanoparticles and HDPE matrix was studied based on Pukanzsky model. To examine the performance of membranes, critical flux, filtration experiment in the MBR, and fouling analysis of membranes were carried out. The results showed that among the fabricated membranes, 0.75 wt % HDPE/ND-PEG membrane had the highest water flux and the best antifouling properties. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47914. 相似文献
55.
A highly efficient solvent-free and simple one-pot approach for the synthesis of 4-hydroxythiazolidine-2-thione is described. The reaction of primary amines and carbon disulfide in the presence of 2-chloroacetaldehyde afforded the title compounds in high yields. 相似文献
56.
SPEEK/cSMM membrane for simultaneous electricity generation and wastewater treatment in microbial fuel cell 下载免费PDF全文
57.
Masoud Beheshti 《电子与电脑》2009,(12):90-92
简介手机、便携式媒体播放器、便携式导航工具及蓝芽(Bluetooth)耳机等新一代手持装置不断缩小体积外型,同时加强效能与功能。就充电管理而言,这些强化的功能使得设计工程人员必须同时顾及用户的便利性与体验感受,以及整体充电时间与成本的均衡。 相似文献
58.
Asghar Alizadehdakhel Masoud Rahimi Jafar Sanjari Ammar Abdulaziz Alsairafi 《International Communications in Heat and Mass Transfer》2009,36(8):850-856
A large number of experiments in a 2 cm diameter and 6 m length tube were carried out in order to study the two-phase flow regimes and pressure drops in it. The two-phase flow in the experimental tube was modeled using commercial CFD code, Fluent 6.2. An Artificial Neural Network (ANN) with three inputs including gas and liquid velocities and tube slope was designed and trained to predict average pressure drop across the tube. The comparison between CFD and ANN predictions of pressure drops with experimental measurements shows that the CFD results are more accurate than the ANN evaluations for new conditions. 相似文献
59.
The effect of bed-load transport on flow resistance of alluvial channels with undulated bed was experimentally investigated.
The experiments were carried out in a tilting flume 250mm wide and 12.5m long with glass-sides of rectangular cross-section
and artificial dune shaped floor that was made from Plexi-glass. Steady flow of clear as against sediment-laden water with
different flow depths and velocities were studied in the experiments with a fine sand (d
50 = 0.5mm). The results indicate that the transport of fine particles (d
50 = 0.5mm) can decrease the friction factor by 22% and 24% respectively for smooth and rough beds. Increasing the bed-load
size (d
50 = 2.84 mm) can decrease the friction factor by 32% and 39% respectively for smooth and rough beds. The decrease in flow resistance
is due to filling up of the troughs of dunes. This separation zone is responsible for increasing the flow resistance. On the
upstream side of dunes condition is similar to plane bed. Presence of bed-load causes to increase the shear velocity and hence
increasing flow resistance. But decreasing in flow resistance is more and it causes to decrease the total flow resistance.
Grains saturated the troughs in the bed topography, effectively helping in smoothening of bed irregularities. 相似文献
60.
The use of composite materials has vastly increased in recent years. Great interest is therefore developed in the damage detection
of composites using non-destructive test methods. Several approaches have been applied to obtain information about the existence,
location and growth of the faults. The main goal in this paper is to use the vibration response of a composite plate to detect
and localize delamination defect based on the frequency response and modal analysis. The features extracted are used as the
input data in an artificial intelligence scheme to identify the severity of the damages. Experiments are then conducted to
validate the developed model. 相似文献