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61.
研究了经熔剂法预处理的碳钢热浸镀ZAS35锌合金工艺、ZAS35锌合金/碳钢双金属制作工艺及双金属界面特性.试验表明,采用700
℃及10 min热浸镀法,铸型预热至500 ℃,ZAS35合金液浇注温度为700 相似文献
62.
Metal‐Organic Frameworks Derived Nanotube of Nickel–Cobalt Bimetal Phosphides as Highly Efficient Electrocatalysts for Overall Water Splitting 下载免费PDF全文
Liting Yan Lei Cao Pengcheng Dai Xin Gu Dandan Liu Liangjun Li Ying Wang Xuebo Zhao 《Advanced functional materials》2017,27(40)
The design of highly efficient, stable, and noble‐metal‐free bifunctional electrocatalysts for overall water splitting is critical but challenging. Herein, a facile and controllable synthesis strategy for nickel–cobalt bimetal phosphide nanotubes as highly efficient electrocatalysts for overall water splitting via low‐temperature phosphorization from a bimetallic metal‐organic framework (MOF‐74) precursor is reported. By optimizing the molar ratio of Co/Ni atoms in MOF‐74, a series of Cox Niy P catalysts are synthesized, and the obtained Co4Ni1P has a rare form of nanotubes that possess similar morphology to the MOF precursor and exhibit perfect dispersal of the active sites. The nanotubes show remarkable hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) catalytic performance in an alkaline electrolyte, affording a current density of 10 mA cm?2 at overpotentials of 129 mV for HER and 245 mV for OER, respectively. An electrolyzer with Co4Ni1P nanotubes as both the cathode and anode catalyst in alkaline solutions achieves a current density of 10 mA cm?2 at a voltage of 1.59 V, which is comparable to the integrated Pt/C and RuO2 counterparts and ranks among the best of the metal‐phosphide electrocatalysts reported to date. 相似文献
63.
双标倒垂孔的施工与控制 总被引:5,自引:0,他引:5
介绍了目前比较成功的倒垂孔钻孔、钻孔偏斜、保护管安装、双金属标的埋设及安装等施工方法和控制措施。 相似文献
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67.
目的 研究不同厚度的Fe Co Ni Cr Cu高熵合金涂层对Al/Mg双金属组织和力学性能的影响。方法 通过超音速火焰喷涂工艺在A356嵌体表面喷涂不同厚度的FeCoNiCrCu高熵合金涂层,采用消失模复合铸造工艺制备Al/Mg双金属,利用扫描电镜、EDS能谱及XRD衍射仪、维氏硬度测试仪和万能试验机对Al/Mg双金属界面微观组织和力学性能进行测试和分析。结果 未喷涂高熵合金涂层的Al/Mg双金属界面由共晶层和金属间化合物层组成,断裂位置主要位于金属间化合物层,裂纹从Al3Mg2扩展至共晶层结束,具有典型的脆性断裂特征,剪切强度仅为30.37 MPa。当高熵合金涂层厚度为5μm时,Al/Mg双金属形成了Al3Mg2+Mg2Si/AlxFeCoNiCrCu+FeCoNiCrCu+Al-Mg-Co-Ni混合相/δ-Mg+Al12Mg17共晶组织的复杂界面,断裂发生在高熵合金层与δ-Mg+Al12Mg17<... 相似文献
68.
《International Journal of Hydrogen Energy》2020,45(3):1784-1792
Ni-based catalysts are considered as an efficient anode material for urea fuel cells due to the low cost and high activity in alkaline media. Herein, we demonstrate that Ni-Co bimetallic hydroxide particles with highly porous nanostructures can be synthesized using mesoporous silica nanoparticles as templates. The replicated nanostructures of the Ni-Co hydroxide samples from the mesoporous silica templates are observed. The porous Ni0.8Co0.2(OH)2 particles exhibited considerably enhanced electro-catalytic activity for urea oxidation reaction by providing a high surface area and fast mass transport for urea oxidation reaction. It is also found that the Co-doping at 20% significantly reduce the overpotential and increase the peak current of urea oxidation reaction. A direct urea/H2O2 fuel cell with the porous Ni0.8Co0.2(OH)2 as anode material shows an excellent performance with maximum power densities of 11.2 and 25.6 mW cm−2 at 20 °C and 70 °C with 0.5 M urea in 5 M KOH, respectively. Thus, this work suggests that the highly porous Ni0.8Co0.2(OH)2-derived from the mesoporous silica templates can be used for urea oxidation and as an efficient anode material for urea-based fuel cells. 相似文献
69.
Kuk-Jin Hwang Mi Jang Min Kyu Kim Seok Hee Lee Tae Ho Shin 《Journal of the European Ceramic Society》2021,41(4):2674-2681
Solid oxide fuel cells (SOFCs) have been gaining increased attention in the energy sector. Commonly, yttria-stabilized zirconia is widely employed as commercial electrolyte, however, resulted in drawbacks such as high-temperature operating and low conductivity which negatively affect the durability and efficiency. Thus there are many efforts to find high-ionic conductors. From the point of manufacturing, the major difficulty of LaGaO3-based electrolyte as a high-ionic conductor is its incompatibility with commercial Ni-based anodes during high-temperature processes as well as operating. Several interlayers have been introduced to prevent the reaction between LaGaO3-based electrolyte and Ni-based anode. In this study, we investigate the optimal thickness of the La-doped CeO2 (LDC) interlayer by the screen-printing method using La0.9Sr0.1Ga0.8Mg0.2O3-δ for the commercial electrolyte supported SOFCs. As a result, the superior power performance of 2.2 W·cm?2 at 1123 K is achieved through the optimized LDC thickness of 20 μm through not lab-scaled but commercial ceramic manufacturing processing. 相似文献
70.
负载镍、铜双金属催化剂的表征及催化性能 总被引:1,自引:0,他引:1
采用活性炭、α-Al_2O_3、硅胶和ZSM-5为载体,制备了负载镍、铜双金属催化剂.用SEM、XRD、XPS测示仪对反应前后的催化剂结构进行了表征.考察了所制备的催化剂在乙醇羰基化反应中的活性,提出了催化剂失活的原因. 相似文献