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铜锍物料经焙烧除硫后,用王水分解,聚氨酯泡沫塑料吸附富集分离试样中金,硫脲解脱后,采用火焰原子吸收光谱(FAAS)法测定金含量。针对该类物料基体复杂的特点,对影响测定结果的各种条件进行了优化实验,确定了最佳分析条件。结果表明:该方法具有较高的准确度和精密度,能够较好地解决铜锍及含铜烧结物中金含量测定难的问题。 相似文献
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本文提出的铜矿石中金的赋存状态分析流程包括:混汞测定解离金;碘—碘化钾溶解连生金;溴—甲醇溶解铜矿中的金;王水溶解黄铁矿中的金;脉石中的金用火试金或经氢氟酸处理后再行测定。设备简单,方法可行。此分析流程测得的分析结果,经有关部门使用效果较好。 相似文献
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巯基棉纤维(简称S.C.F.)富集和分离由于简单、易行和便于普及,已在环境样品分析中多有应用,用于贵金属实样分析则仅见于矿石中金和冶金物料中金和钯的分离及测定。本文研究了盐酸介质中七种贵金属元素和铜、镍、铁、钴等在S.C.F.上的吸附行为,拟订了从相应冶金物料中富集和分离金、钯及铂的方法。即先在3 N盐酸中用S.C.F.吸附金和钯,然后向流出液中入少量氯化亚锡,再用S.C.F.吸附铂。被吸附的铂可用2 N氢氧化钠溶液定量洗脱,而金和钯则需将S.C.F.同硝酸、高氯酸和硫酸一起冒烟破坏,然后分别转化成盐酸溶液,用分光光度法测定。方法 相似文献
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容量法测定金合金中的金 总被引:4,自引:0,他引:4
对重铬酸钾滴定过量硫酸亚铁返滴定法测定金合金中金的主要问题做了探讨和实验.拟定了简便、准确的测定方法,方法的重现性好,金含量为60%~99%时的相对标准偏差<0.2%. 相似文献
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西昆仑苦阿金铁矿床为与火山-沉积作用有关的沉积变质型矿床。对矿床矿石的物质组成、矿石中金的成色、赋存状态及粒度进行论述,并加强矿石选冶性能研究,为开展区域性金矿评价和开发利用提供指导意义。 相似文献
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为解决湿法溶解处理测定杂铜中金的基体干扰,采用硝酸湿法分离基体铜,再用王水溶解金。在5%的盐酸介质中,在设定的仪器工作条件下,用火焰原子吸收光谱法测定杂铜中的金。方法相对标准偏差为0.5%,该法简单快速、准确可靠。 相似文献
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A. Y. Shinyaev 《Metal Science and Heat Treatment》1994,36(8):404-406
In the development of high-temperature alloys the use of refractory metals with a high melting point — Ta and W — for alloying is becoming conventional. These metals, and also the alloys based on them, may come into contact with metals and alloys whose melting points are much lower (for example, in composite-type materials). Upon heating there develop in the areas of contact of the metals differing in their melting point the processes of mutual diffusion, knowledge of which makes it possible to determine the chemical composition of the transition zone and the thermal stability of the composite material. Since production of the refractory metals involves great difficulties, intermediate products are prepared from them by the powder metallurgy method. The powder materials contain more defects, particularly pores, in comparison with the cast materials, which must be considered in studying the diffusion. In the present article we examine on the basis of experimental data and thermodynamic analysis the characteristics of the kinetics of the process of mutual diffusion of vanadium and the refractory metals in cast and powder variants at various temperatures.All-Union Scientific Research Institute of Hard Alloys. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 8, pp. 9–11, August, 1994. 相似文献
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把原粘土砂湿型生产法兰主轴铸件的工艺改为覆砂铁型工艺,解决了内部缩松等一系列缺陷问题。与原工艺相比,实现了覆砂铁型工艺的"多、快、好、省"。 相似文献
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The reactions of methane with the gold complexes [Au(OH)]−, [Au(OCH3)4]−, [Au(O(CO)2O2]− and [Au(O2CH)2]+, [AuI(acac)], [AuIII(acac)2]+ (acac-acetylacetonato) were studied using the DFT/PBE method with the SBK basis set. High activation barriers were obtained for
the electrophilic substitution in [Au(OH)]−, [Au(OCH3)4]−, [Au(O(CO)2O)2]-and [AuIII(acac)2]+ complexes, which excludes the possibility that these reactions might proceed under mild conditions. The reactions of the
[Au(HCO2)2]+ and [AuI(acac)] complexes with methane have rather low energy barriers and proceed through the formation of an intermediate complex. The
alternative mechanism of methane oxidation with a gold complex in the presence of oxygen is simulated. 相似文献
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移动式三轴三混可升降式树脂砂混砂机采用双槽低速预混搅笼和终混高速搅笼新工艺,比普通混砂机多一轴,解决了双轴双混和单轴单混两种混砂机混砂效果差的问题。 相似文献
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