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81.
82.
Microstructure and corrosion properties of thick WC composite coating formed by plasma cladding 总被引:1,自引:0,他引:1
The thick Ni-coated WC coatings, in a matrix of Nickel-based alloys, were prepared on AISI 1045 steel using plasma cladding equipment. A pre-placed layer of uniform mixture, with different weight fractions of Ni-coated WC powder and Nickel-based alloy powder, on the steel substrate was melted at the high temperature of the plasma jet. The coating composition, microstructure and microhardness were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectrometer (EDS) and microhardness testing. The experimental results show that the metallurgical bond was formed between the coating and substrate. The XRD results show that the coatings contain γ-Ni, carbides (such as M23C6 and M7C3) and boride (such as Fe2B, Fe3B phases). SEM shows that all the coatings are crack-free with lower porosity (<1%). It is found that the microhardness and the electrochemical behavior of the coatings are depended on the content of Ni-coated WC powder. The corrosion mechanism for the coatings may be due to the microgalvance corrosion between the phases in the cladding coatings. 相似文献
83.
Accelerated projection-based forward-backward splitting algorithms for monotone inclusion problems
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In this paper, based on inertial and Tseng''s ideas, we propose two projection-based algorithms to solve a monotone inclusion problem in infinite dimensional Hilbert spaces. Solution theorems of strong convergence are obtained under the certain conditions. Some numerical experiments are presented to illustrate that our algorithms are efficient than the existing results. 相似文献
84.
根据D-T反应中子的能谱和角分布数据,建立了中子源模型;根据石灰岩地层标准刻度井群数据,建立了井模型。采用MCNP程序模拟了井中中子和射线的输运,得到了不同地层密度、不同源距处NaI探测器中的混合能谱和非弹能谱。在混合能谱2.5~4.5 MeV能区开窗,混合射线相对计数随源距的变化曲线显示,源距应选择在20~80 cm,密度与混合射线计数之间呈现非线性关系。在非弹能谱1.0~8.0 MeV能区开窗,非弹射线相对计数随源距的变化数据显示,源距应选择在20~40 cm或80 cm附近,密度与非弹射线计数之间成近似线性关系。 相似文献
85.
In this paper, fixed point and equilibrium problems are considered based on a hybrid projection method. Strong convergence theorems of common elements are established in the framework of real Hilbert spaces. 相似文献
86.
The major aim of the note is to strengthen the results of Asaad in Communications in Algebra, 42 (2014), 2319–2330. 相似文献
87.
讨论了有序Banach空间E中的非线性二阶周期边值问题-u″(t)+bu′(t)+cu(t)=f(t,u(t)),0≤t ≤ ω,u(0)=u(ω),u′(0)=u′(ω)正解的存在性,其中b,c∈R且c>0,f:[0,ω]×P→P连续,P为E中的正元锥.本文通过新的非紧性测度的估计技巧与凝聚映射的不动点指数理论,获得了该问题正解的存在性结果. 相似文献
88.
Linxing Meng Xiaolong Zhou Siyu Wang Yu Zhou Wei Tian Pinit Kidkhunthod Sarayut Tunmee Yongbing Tang Run Long Yu Xin Liang Li 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(46):16821-16828
A photoelectrochemical (PEC) cell can split water into hydrogen and oxygen with the assistance of solar illumination. However, its application is still limited by excessive bulk carrier recombination and sluggish surface oxygen evolution reaction (OER) kinetics. Taking SnS2 as an example, a promising layered optoelectronic semiconductor, Ar plasma treatment strategy was used to introduce a SnS/SnS2 P?N heterojunction and O?S bond near the surface of a SnS2 nanosheet array, simultaneously increasing the separation efficiency of photogenerated electron–hole pairs in the bulk and lowering the OER overpotential at the surface. The onset potential of the plasma‐treated SnS2 nanosheet array shifts negatively to 0.16 V, and the photocurrent density at 1.23 V vs. RHE boosts to 2.15 mA cm?2, which is 7 times that of pristine SnS2. This work demonstrates a facile plasma treatment strategy to modulate the energy band structure and surface chemical states for improved PEC performance. 相似文献
89.
Chen Hanchi Cai Xiaoqing Xu Anjie Zhu Linjiang Lu Yuele Chen Xiaolong Liu Shijie 《Applied biochemistry and biotechnology》2019,189(2):345-358
Applied Biochemistry and Biotechnology - Glucose phosphorylation by glucokinase exhibits a sigmoidal dependency on substrate concentration regardless of its simple structure. Dimorph mechanism... 相似文献
90.