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21.
In this contribution, a novel sulfate‐ion‐controlled synthesis is developed to fabricate freestanding nickel hydroxide nanoarrays on Ni substrate. As an inorganic morphology‐controlled agent, SO42− ions play a critical role in controlling the crystal growth and the nanoarray morphologies, by modulating the growth rate of adsorbed crystal facets or inserting into the metal hydroxide interlayers. By controlling the SO42− concentration, the nanostructured arrays are tailored from one‐dimensional (1D) Ni(SO4)0.3(OH)1.4 nanobelt arrays to hierarchical β ‐ Ni(OH)2 nanosheet arrays. With further graphene oxide modification and postheat treatment, the obtained NiO/graphene hybrid nanoarrays show great potential for high‐performance sodium‐ion batteries, which exhibit a cyclability of 380 mAh g−1 after undergoing 100 cycles at 0.5 C and reach a rate capability of 335 mA h g−1 at 10 C. 相似文献
22.
《材料科学技术学报》2019,35(8):1797-1802
A new insight into the promotion action of Co2+ on both particle and metal deposition in Ni-diamond composite electrodeposition system was analyzed according to electrochemical measurements. The results showed that the addition of Co2+ made particles content in deposits increased remarkably. The change of particles content in deposits was related inversely to the change of cathodic zero potential with the increase of the concentration of cobalt sulfate. Zero charge potential of cathode was shifted to much more negative region. The negative shift of the zero potential, combining with positive shift of the zeta potential, increased the electrostatic force between the particle-adsorbed metallic cations and the cathode. It not only benefits to the transportation of particles in solution towards cathode, but also shortens their residence time on cathodic surface. Meanwhile, entry of particles is also promoted. For metals deposition, reduction resistance of metallic cations rises greatly and deposition current at cathodic potentiodynamic polarization decreases after cobalt sulfate has been added into electrolyte. These factors are favorable for increasing particles content in deposits. In addition, physical model of diamond particles deposition state before and after the addition of Co2+ has been discussed. 相似文献
23.
Liquid–liquid phase diagrams of surfactant-based aqueous two-phase systems (ATPS) composed of TritonX-100, as a non-ionic surfactant, and two different salts have been studied at 298.15 K. The salts used were an inorganic salt, magnesium sulfate (MgSO4), and an organic salt, sodium citrate (Na3C6H5O7). The results show that the salt MgSO4 is more capable of inducing ATPS formation than the salt Na3C6H5O7. The experimental liquid–liquid equilibrium data were correlated using a modified virial model. Good agreement was obtained with the experimental data. 相似文献
24.
遵义锰矿地质特征及找矿潜力分析 总被引:3,自引:0,他引:3
遵义锰矿系指产于二迭系上统龙潭组底部以碳酸盐锰矿石为主的沉积型锰矿,几乎全部集中分布于遵义市及其附近地区。文章通过对遵义锰矿区域地质背景,矿区地质特征和矿体特征、矿床成因、找矿标志的分析,对该区找矿潜力进行了分析。 相似文献
25.
H. Hofmann D. Mattissen T. W. Schaumann 《Materialwissenschaft und Werkstofftechnik》2006,37(9):716-723
Advanced multiphase steels offer a great potential for bodies‐in‐white through their combination of formability and achievable component strength levels. They are first choice for strength and crash‐relevant parts of challenging geometry. The intensive development of high‐strength multiphase steels by ThyssenKrupp has led to hot dip galvanizing concepts with an outstanding forming potential. Hot rolled, hot dip galvanized complex phase steels are currently produced in addition to cold rolled DP and RA steels. New continuously annealed grades with tensile strength levels of up to 1000 MPa in combination with sufficient ductility for applications mainly in the field of structural automobile elements make use of the classic advantages of microalloying as well as the principles of DP and TRIP steels. Further improvement of properties will be reached by the new class of high manganese alloyed steels. 相似文献
26.
27.
中国锰系铁合金的发展与思考 总被引:3,自引:0,他引:3
对近年来我国锰系铁合金的产量、表观消耗量、进出口量及锰矿资源、进口量进行了汇总,并对锰系合金与锰矿的需求与走势进行了量化分析。还对我国生产的纯钢消耗数据给出了统计分析。此外,文章对我国锰矿进口对策浅述了作者的设想。 相似文献
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29.
贵州省铜仁锰业的思考 总被引:1,自引:1,他引:1
针对贵州省铜仁锰业锰产品开发市场、有利条件和限制因素,提出了做大做强铜仁锰业的具体措施和建议。 相似文献
30.
羟胺低温磷化 总被引:2,自引:1,他引:2
为解决当前磷化工艺中存在的高温、多渣等不足,通过羟胺类低温磷化促进剂与其他传统磷化促进剂相复配,采用正交试验的方法研究了一种新型的低温磷化工艺.试验结果表明,羟胺具有优异的促进作用,硫酸羟胺是较好的室温促进剂,单独使用时的最低用量为5 g/L,与氯化钠配合使用可大大降低其有效用量,最低成膜浓度2 g/L,并能改善膜层的耐碱性.最佳磷化配方为:ZnO 10 g/L,HNO3 10 mL/L,H3PO4 15 mL/L,HAS 2 g/L, NaClO3 1.0 g/L,有机酸3.0 g/L钼酸钠0.04 g/L,促进剂A适量;酸度比 7~12;pH值 1~2;磷化时间 15~20 min;磷化温度 30 ℃.磷化膜均匀呈灰黑色,膜重8~12 g/m2,硫酸铜点滴≥130s. 相似文献