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991.
运用往复线性摩擦试验方法,搭配自制的摩擦试验夹具,模拟织造过程中氧化铝纤维束-筘齿的摩擦行为,研究加载力、预加张力和摩擦频率对悬空状态下氧化铝纤维束摩擦磨损性能的影响.结果表明:随着加载力的增加,氧化铝纤维束所受摩擦力及长丝断裂根数增加,摩擦系数减小;在预加张力为0.40 N时,氧化铝纤维束所受摩擦力和摩擦系数出现最小值,磨损程度也最小;在摩擦稳定阶段,摩擦频率增加,则氧化铝纤维束所受摩擦力先下降,后略有上升,当摩擦频率增加至5 Hz时,氧化铝纤维束的摩擦系数较1 Hz时增加18.7%,磨损程度也最为严重. 相似文献
992.
993.
Telecommunication Systems - Wireless sensor networks (WSNs) and Internet of Things domain comprise of numerous small sized battery powered sensor nodes. Energy efficiency and energy balancing are... 相似文献
994.
995.
Multidimensional Systems and Signal Processing - In medical Image processing, the chief objective is to detect Neoplasm effectively. Neoplasm is basically a sort of abnormal excessive cell growth... 相似文献
996.
Design Automation for Embedded Systems - Moving object tracking is a computation-intensive operation that requires accelerating hardware solution. In this work, a high-performance design for mean... 相似文献
997.
Kashin V. A. Shurygina I. S. 《Journal of Communications Technology and Electronics》2021,66(10):1155-1162
Journal of Communications Technology and Electronics - Abstract—A simple approach to creating multibeam patterns is considered, when there is one microwave input/output, and a set of beams is... 相似文献
998.
Wireless Networks - Rendezvous (RDV) in cognitive radio ad-hoc networks (CRAHNs) is one of the key ways for a pair of unknown cognitive radio users to initiate communications. CRAHN is a... 相似文献
999.
H. Alrobei M.K. Prashanth C.R. Manjunatha C.B. Pradeep Kumar C.P. Chitrabanu Prasanna D. Shivaramu K. Yogesh Kumar M.S. Raghu 《Ceramics International》2021,47(7):10322-10331
In the present study we made an effort to deploy eco-friendly synthesized reduced graphene oxide/Lanthanum Alluminate nanocomposites (RGO-LaAlO3) and Lanthanum Alluminate (LaAlO3) as adsorbents to remove dye from the synthetic media. XRD, SEM, BET surface area and EDX have been used to characterize the above-mentioned adsorbents. The impacts of different factors like adsorbent dosage, the concentration of adsorbate and PH on adsorption were studied. The best fit linear and nonlinear equations for the adsorption isotherms and kinetic models had been examined. The sum of the normalized errors and the coefficient of determination were used to determine the best fit model. The experimental data were more aptly fitted for nonlinear forms of isotherms and kinetic equations. Pseudo-second-order and Freundlich isotherm model fits the equilibrium data satisfactorily. Methyl orange (MO) has been used as model dye pollutant and maximum adsorption capacity was found to be 469.7 and 702.2 mg g?1 for LaAlO3 and RGO-LaAlO3, respectively. 相似文献
1000.
To investigate the evolution of the structural and enhanced magnetic properties of GdMnO3 systems induced by the substitution of Mn with Cr, polycrystalline GdMn1-xCrxO3 samples were synthesized via solid-state reactions. XRD characterization shows that all GdMn1-xCrxO3 compounds with single-phase structures crystallize well and that Cr3+ ions entering the lattice sites of GdMnO3 induce structural distortion. SEM results indicate that the grain size of the synthesized samples (a few microns) decreases as the Cr substitution concentration increases. Positron annihilation lifetime spectroscopy reveals that vacancy-type defects occur in GdMn1-xCrxO3 ceramics and that the vacancy size and concentration clearly change with the Cr content. The temperature and field dependence of the magnetization curves show that Cr substitution significantly influences the magnetic ordering of the gadolinium sublattice, improving the weak ferromagnetic transition temperature and magnetization of GdMn1-xCrxO3. The enhanced magnetization of GdMn1-xCrxO3 is closely related to the vacancy defect concentration. 相似文献