共查询到20条相似文献,搜索用时 46 毫秒
1.
锌锡合金经盐酸-过氧化氢溶解,在氯化铵存在下,以铁盐做载体,用氨水沉淀分离锡等杂质元素,经二次沉淀分离消除沉淀对锌的吸附作用。经蒸发除氨,在p H值5~6的醋酸-醋酸钠缓冲溶液中,以二甲酚橙为指示剂,用EDTA标准溶液滴定。此方法准确可靠,干扰少,重现性好,已用于实际样品的分析检测,对实际分析工作有指导作用。 相似文献
2.
锌锭样品用盐酸溶解后,在氨性介质中加入Al3+,锡铅锑铋离子与氢氧化铝共沉淀后,用盐酸(2+98)溶解沉淀,氢化物发生-原子荧光光谱法测定锡铅锑铋。选择0.10 mol/L的Al3+加入量为4.0~5.0 mL,共沉淀时间为30 min,用10 mL 0.1 mol/L的氨水洗涤沉淀符合共沉淀要求且不会造成沉淀损失。基体锌及试液中引入的Al3+对测定均不产生干扰。方法用于锡铅锑铋的质量分数大于0.001%的锌锭中几种离子的测定,结果满足分析要求。 相似文献
3.
从合金丝废料回收铅,锡和铟 总被引:1,自引:0,他引:1
用酸/碱浸出法从含铅、锡和铟的合金丝废料中成功地回收了这些金属。用热的HCl-HNO3浸出废料,冷却至10℃时,最初存在的71.8%铅以氯化铅分离出来。在45℃下,用每当量铅1.5当量的铟粉转换沉淀回收其余大部分铅(22.9%)。在pH2.0 ̄2.8时,用NaOH以水合氧化锡形式从酸性溶液中回收锡。用两种不同方法从残液中回收铟。第一种方法是在pH3.91时,用H3PO4以磷酸盐形式沉淀铟,用NaO 相似文献
4.
5.
6.
研究了钢铁中微量锡的分析,使用P-E5000型原子吸收分光光度计,利用高温石墨炉技术,样品经酸溶解后进样20ul,经石墨炉原子化后,将锡的吸光度计算转换成浓度值接打出印出钢铁中微量锡的分析结果,此方法简单,干扰少,分析速度快。灵敏度高,精密度能满足要求,可分析钢中0.0002%-0.020%锡的含量。 相似文献
7.
研究了对一二甲胺基苄叉绕丹宁沉淀吸附分离光度法测定铜精矿中的银。在20毫升0.1mol/L HNO3介质中,2mg试剂产生的沉淀可迅速吸附0-10μg银,回收率达到98%以上。沉淀用浓HNO3溶解后,分光光度法测定银。本法可测定铜精矿中**-***g/t的银。 相似文献
8.
9.
原子吸收法测定银铜锌锡合金和铜合金中的锡 总被引:3,自引:0,他引:3
用浓硝酸和浓硫酸溶样,以空气-乙炔火焰原子吸收法测定银铜锌锡合金和铜合金中的锡,测定范围为0.02% ̄10.12%。 相似文献
10.
11.
12.
Comments on A. R. Fiester's (see record 1979-26797-001) analysis of the Joint Commission on Accreditation of Hospitals standards for accreditation of community mental health centers (CMHCs) and addresses some additional issues, including the financial future of CMHCs and the influence of the Balanced Service System model on various aspects of accountability and responsibility. These standards may pose problems for psychiatric facilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
13.
Wang Xiangbin Pan Yi Lados Diana A. 《Metallurgical and Materials Transactions B》2018,49(4):2097-2117
Metallurgical and Materials Transactions B - Friction stir welding is a solid-state welding technique that has many advantages over traditional fusion welding, and has been widely adopted in the... 相似文献
14.
金属陶瓷既保持了陶瓷材料优异特性,又具备金属材料优势,是一种重要的新型工程材料。本文利用粉末冶金方法制备氧化铝-铝金属陶瓷材料,研究其致密化机理,为制备高性能金属陶瓷材料提供参考。研究表明,随着Al含量的降低,金属陶瓷材料的致密度逐渐降低。在扫描电镜图片中,颗粒呈连续分布且较大的为金属Al颗粒,颗粒呈不连续分布较细小的为Al2O3颗粒。随着Al含量的降低,金属陶瓷材料的晶界数量逐渐增多。随着Al含量由75%(质量分数,下同)减至25%时,硬度依次下降,Al含量高,易熔融相多,Al2O3粉末相对少,Al能较好较充分的将Al2O3粉末包裹住,且致密化效果好,故样品整体有较高的硬度。随着Al含量的降低,样品的导电性逐渐变差。 相似文献
15.
16.
17.
18.
Wettability of liquid A359 alloy on SiC particles under molten salt NaCl-KCl-NaF is found at 180 deg, meaning that SiC particles
prefer the molten salt phase against the Al phase or the Al/molten salt interface. Thus, this molten salt can be used for
recycling, i.e., to separate the phases in the SiC reinforced Al matrix composites. If the separation process is interrupted, Al droplets
(submillimeter solidified powder) can be produced, stabilized/surrounded by a monolayer of shielding SiC particles. 相似文献
19.
Mojtaba Jafarian Mohsen Saboktakin Rizi Morteza Jafarian Hossein Zare Hamid Reza Javadinejad 《Transactions of the Indian Institute of Metals》2018,71(12):3011-3020
In the present study, microstructural and mechanical properties of diffusion bonding of AZ31–Mg with Al 5754, Al 6061, and Al 7039 alloys were compared under same conditions. The vacuum diffusion processes were performed at a temperature of 440 °C, the pressure of 29 MPa, and a vacuum of 1?×?10?4 torr for 60 min. The microstructural characterizations were investigated using optical microscopy and scanning electron microscopy equipped with EDS analysis and linear scanner. The XRD analysis was performed to study phase figures near the interface zone. The results revealed the formation of brittle intermetallic compounds like Al12Mg17, Al3Mg2, and their other combinations at bonding interfaces of all samples. Additionally, the hardness of Al alloys seemed to play a key role in increasing diffusion rate of magnesium atoms toward the aluminum atoms, with Al 6061 alloy having the highest diffusion rate. It consequently led to an increase in diffusion rate and thus formation of a strong diffusion bonding between magnesium and aluminum alloys. The highest strength was about 42 MPa for the diffusion bonding between Mg AZ31 and Al 6061. Further investigations on surfaces indicated that the brittle phases especially Al3Mg2 caused brittle fracturing. 相似文献