共搜索到74853条信息,每页显示10条信息,共7486页。用时:0小时0分1秒703毫秒
积的钴会出现明显的返溶现象.这是因为Cu2+首先被锌粉置换,与Zn组成Cu-Zn微电池,沉积的铜成为微电池中Co2+沉积的阴极基底,Co在铜阴极上的析出有较正的电势,有利于钴的沉积;但是当Cu2+浓度高于一定范围时,反而对除钴有害,因为H+在Cu上的放电过电势低于在Zn上的放电过电势,所以Cu2+大量沉积会使H+大量放电,造成锌粉表面上的pH上升,而溶液中Zn2+浓度又很高,于是在锌粉表面形成碱式...向溶液中加入一定量硫酸铜或一段净化时保留少量铜和镉的方法,实现了深度净化除钴.关于其作用机理,开展了大量的研究.一些研究者认为,Cu2+的作用是降低Co的超电势,增大锌钴微电池电势差,从而增大置换过程的热力学推动力[1,7-9],Cd2+可起到阻止碱式硫酸锌或氢氧化锌吸附在锌粉表面的作用[10];另一些研究者认为,Cu2+和Cd2+首先被锌粉置换出来,形成Co沉积的基底[11-14],提高锌粉净化......
Cu bulk and CNTs /Cu composite with different electrical currents. The worn surfaces of pure Cu bulk reveal not only intensive abrasive and adhesive wear with deep grooves but also a mass of oxide... Effect of electrical current on tribological property of Cu matrix composite reinforced by carbon nanotubes XU Wei1, 2, HU Rui1, LI Jin-shan1, FU Heng-zhi1 1. State Key Laboratory......
by bonding together. Key words: liquid metal Cu; molecular dynamics simulation; Q-SC multi-body potential; microstructure evolution; nucleation; growth 受具体实验条件的限制,对金属熔体凝固过程中晶体成核生长和微观结构的精确测定尚比较困难.但近年来...文章编号:1004-0609(2015)10-2863-08 液态金属铜Cu凝固过程中团簇结构的形成以及成核生长特性的模拟 易学华 (嘉应学院 物理与光信息科技学院,梅州 514015) 摘 要:采用分子动力学方法和Quantum Sutton-Chen多体势,对2万个液态金属铜(Cu)原子在两个不同冷速凝固过程中其微观团簇结构的形成特性以及晶体的成核生长进行模拟.运用双体分布函数......
and DTA. Microstructure of Sm(Co, Cu, Fe, Zr)z-sintered magnets was analyzed through SEM and EDS.The results indicate that the antioxidation effect of the alloy powder treated in silane solution is better... solution is not suitable for metal injection molding (MIM) because it severely damages the magnetic properties and microstructure of Sm(Co, Cu, Fe, Zr)z-sintered magnets. SA solution can not only......
Microstructure evolution of semi-solid 2024 alloy during two-step reheating process WANG Shun-cheng(王顺成), LI Yuan-yuan(李元元), CHEN Wei-ping(陈维平), ZHENG Xiao-ping(郑小平) School of Mechanical...-liquid zone temperature. Microstructure evolution of the semi-solid billet during two-step reheating was studied by optical microscope and compared with that during isothermal reheating. The results show......
机磷酸类-羟肟体系 螯合羟肟萃取剂与有机磷酸混合有机相对钴和镍表现出很强的协同效应,如LIX 63+P204,LIX 63+P507等体系明显增大了钴和镍的分离系数[7].CHENG等[8-9]采用LIX 84+Cyanex 272体系从钴,镍溶液中分离出铜,铁和锌,铜,铁和锌与钴,镍的分离系数达到3×105,其中,100% Fe和超过97%(Cu+Zn)(质量分数)进入有机相,共萃取的钴,镍含量...; synergistic solvent extraction; separation 钴和镍在工业中占据着重要地位,主要应用于航空,航天,电子和电池等领域.随着国民经济的增长,钴和镍的消费量迅速增长,而钴和镍资源日益枯竭,低品位的钴,镍氧化矿和硫化矿逐渐被开采,这种矿石宜采用湿法冶金工艺处理.近年来,低品位矿的湿法冶金技术得到了很大的发展,特别是生物浸出技术和各种组合的溶剂萃取工艺.生物浸出液中成分复杂......
clearly disclose a microstructure evolution of films upon doping Cu. Doping Cu can effectively suppress film grain growth, causing a small grain size as well as uniform size distribution. Furthermore... improved, which makes them promising candidates for various applications. Key words: beryllium; thin films; Cu doping; microstructure 1 Introduction Beryllium (Be), one of the lightest elements (Atomic......
火焰原子吸收光谱法连续测定钴矿中Co,Ni和Cu 王旭珍1,冯学珠1,唐清华1,张秀香1 (1.烟台师范学院化学系,山东,烟台,264025) 摘要:用HCl-HNO3-KClO3溶解试样,在几个相同量的试液中,分别加入浓度依次递增的3种元素的标准溶液,用空气-乙炔火焰原子吸收法连续测定Co,Ni和Cu的含量.建立了优化的仪器测定条件,并对可能存在的元素进行了干扰试验.钴,镍,铜的回收率为98.3%~101.0%,相对标准偏差为0.76%~2.31%. 关键词:原子吸收光谱法; 钴矿; Co; Ni; Cu; [全文内容正在添加中] ......
: ψ(BCC-Cu)=[Ar](3dn)5.26(3dc)4.37 (4sc)0.08 (4sf)1.29, ψ(BCC-Ag)=[Kr](4dn)5.75(34dc)3.29(5sc)1.84(5sf)0.13, ψ(BCC-Au)=[Xe](5dn)4.00(5dc)5.18 (6sc)1.20(6sf)0.62. 4 初态液体LIQUID-Cu, Ag, Au的电子结构 与HCP和BCC初态特征晶体的情况类似, 由SGTE数据库晶格稳定参数可求得初体LIQUID-Cu, Ag, Au的结合能依次为Ec(L-Cu)= 323.035kJ/mol, Ec(L-Ag)=272.975kJ/mol, Ec(L-Au)=355.448kJ/mol. 假定Cu, Ag, Au在熔化后仍具有FCC短程有序结构, 则根据其在熔化前后的密度[25]及固态FCC-Cu, Ag......
treatment on microstructure and electrochemical performances of Co-free MlNi4.0Al0.3Si0.1Fe0.6 hydrogen storage alloy [J]. The Chinese Journal of Nonferrous Metals, 2004, 14(11): 1862-1868. (in Chinese...Article ID: 1003-6326(2005)05-1021-05 Influence of Cr or Co doping on electrode properties of V2.1TiNi0.5Hf0.05 hydrogen storage alloy CHEN Li-xin(陈立新), GUO Rui(郭 蕊), LI Lu(李 露), LEI......