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941.
X. Li T. Liu P. Lin W. Xiang H. Shang Y. Liu S. Zhang 《Materialwissenschaft und Werkstofftechnik》2023,54(1):98-108
Carbon fiber reinforced composites have attracted lots of attention in many fields. However, on account of the poor infiltration of resin to carbon fiber, the weak interface performance between fiber and resin has been restricting the interface properties of composites. In recent progress, the review attaches more importance to the introduction of the third phase monomer, which mainly uses physical and chemical methods to assemble nanomaterials (such as carbon nanotubes, graphene, etc.) on the carbon fiber surface to modify the interface structure of the carbon fiber reinforced composites, and all of them have been demonstrated in this paper. Furthermore, the effects of introducing nanomaterials on the structure of the fiber/resin interface and the relationship between multi-scale interface structure and properties have been investigated. It can be seen that the design idea of researchers mainly uses one or more theories to improve the interface properties of carbon fiber reinforced composites, such as transition layer, chemical bonding, mechanical interlocking, infiltration, diffusion, and adsorption. In brief, this work provides some novel insights for the preparation of carbon fiber reinforced composites with excellent interlaminar shear strength. 相似文献
942.
Yahuan Huan Tiantian Luo Xiaocang Han Jun Ge Fangfang Cui Lijie Zhu Jingyi Hu Feipeng Zheng Xiaoxu Zhao Lili Wang Jian Wang Yanfeng Zhang 《Advanced materials (Deerfield Beach, Fla.)》2023,35(1):2207276
Exploring new-type 2D magnetic materials with high magnetic transition temperature and robust air stability has attracted wide attention for developing innovative spintronic devices. Recently, intercalation of native metal atoms into the van der Waals gaps of 2D layered transition metal dichalcogenides (TMDs) has been developed to form 2D non-layered magnetic TMDs, while only succeeded in limited systems (e.g., Cr2S3, Cr5Te8). Herein, composition-controllable syntheses of 2D non-layered iron selenide nanosheets (25% Fe-intercalated triclinic Fe5Se8 and 50% Fe-intercalated monoclinic Fe3Se4) are firstly reported, via a robust chemical vapor deposition strategy. Specifically, the 2D Fe5Se8 exhibits intrinsic room-temperature ferromagnetic property, which is explained by the change of electron spin states from layered 1T'-FeSe2 to non-layered Fe-intercalated Fe5Se8 based on density functional theory calculations. In contrast, the ultrathin Fe3Se4 presents novel metallic features comparable with that of metallic TMDs. This work hereby sheds light on the composition-controllable synthesis and fundamental property exploration of 2D self-intercalation induced novel TMDs compounds, by propelling their application explorations in nanoelectronics and spintronics-related fields. 相似文献
943.
在对垃圾处理现状进行系统的调查研究的基础上,作者提出了湖北省城镇垃圾处理的合理改革与相应措施. 相似文献
944.
简斌 《土木与环境工程学报》1998,20(4):1-7
变刚度分析法是一种解预应力超静定结构问题的便易行且精度较高的分析方法,该分析方法的计算结果与屡系列大型试验所验证。 相似文献
945.
K. Kumagai S. Ikeda J. Jiang M. S. Lin C. C. Lai H. C. Ku 《Journal of Low Temperature Physics》1996,105(5-6):1641-1646
195Pt-,139La- and11B-NMR have been investigated in quaternary RM2B2C (R=Y, La, Th and M=Ni, Pd, Pt). The electric quadrupole frequency of139La changes more than 5 times in magnitude from M=Ni to Pt, indicating that the hybridization of La-5d and d-electrons of M-element changes largely. The analysis of11B and139La spectra shows also the large change of the magnetic anisotropy with R and M element, i.e., II c>II ab in LaNi2B2C, but II c>II ab YNi2B2C.The data of T1T and K of195Pt and11B are consistent with the band effects and with no evidence of strong antiferromagnetic correlation effects. 相似文献
946.
947.
P. Jian D. G. Ivey R. Bruce G. Knight 《Journal of Materials Science: Materials in Electronics》1996,7(2):77-83
A detailed microstructural study has been done on Au-Pd-Zn ohmic contacts to p-type InGaAsP epitaxially grown on InP. The doping level in the InGaAsP was 1.0 × 1019 to 1.5 × 1019 cm–3 near the surface with the Zn concentration graded to a value of 7 × 1018 cm–3 at the InGaAsP-InP interface. Metal layers (10 nm Pd,3 nmZn, 25 nm Pd and 50 nm Au) were deposited sequentially by electron beam evaporation. Contact resistances less than 10–4 cm2 were achieved for all annealing temperatures studied (380–440 C) and a minimum contact resistance of 2 × 10–6 cm2 was obtained for an anneal at 400 C for 20 s. Comparisons were made to similar metallizations on p-type InP. Lower contact resistances were achieved for the quaternary material compared with the binary material, however, contact stability and uniformity were worse. 相似文献
948.
949.
Ensemble of surrogates with recursive arithmetic average 总被引:2,自引:0,他引:2
Xiao Jian Zhou Yi Zhong Ma Xu Fang Li 《Structural and Multidisciplinary Optimization》2011,44(5):651-671
Surrogate models are often used to replace expensive simulations of engineering problems. The common approach is to construct
a series of metamodels based on a training set, and then, from these surrogates, pick out the best one with the highest accuracy
as an approximation of the computationally intensive simulation. However, because the choice of approximate model depends
on design of experiments (DOEs), the traditional strategy thus increases the risk of adopting an inappropriate model. Furthermore,
in the design of complex product system, because of its feature of one-of-a-kind production, acquiring more samples is very
expensive and intensively time-consuming, and sometimes even impossible. Therefore, in order to save sampling cost, it is
a reasonable strategy to take full advantage of all the stand-alone surrogates and then combine them into an ensemble model.
Ensemble technique is an effective way to make up for the shortfalls of traditional strategy. Motivated by the previous research
on ensemble of surrogates, a new technique for constructing of a more accurate ensemble of surrogates is proposed in this
paper. The weights are obtained using a recursive process, in which the values of these weights are updated in each iteration
until the last ensemble achieves a desirable prediction accuracy. This technique has been evaluated using five benchmark problems
and one reality problem. The results show that the proposed ensemble of surrogates with recursive arithmetic average provides
more ideal prediction accuracy than the stand-alone surrogates and for most problems even exceeds the previously presented
ensemble techniques. Finally, we should point out that the advantages of combination over selection are still difficult to
illuminate. We are still using an “insurance policy” mode rather than offering significant improvements. 相似文献
950.
刘建 《计算机测量与控制》2011,19(12)
从现有车辆导航系统的基本原理和组成出发,结合我国自主的北斗卫星导航系统,综合应用通信、控制、GIS等多种技术,提出了一种兼容自主式和中心式车辆导航系统的设计,并重点讨论了控制中心和移动终端的实现方案,控制中心通过采集实时交通信息,进行分析处理后形成最优的路径规划,移动终端根据自身所在的位置区域获取相应的诱导信息,使城市的交通流趋向最优分布,减少车辆在道路上的逗留时间,从而有效地改善城市交通状况,减少交通拥堵. 相似文献