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21.
铜阳极泥预处理脱铜工艺优化   总被引:3,自引:0,他引:3  
分析了铜阳极泥预处理过程中有价元素Cu、Te、As的分布状况及工艺存在的问题,提出了铜阳极泥预处理过程工艺优化方案。结果:一,中间物料如吸收后液、银过量还原后液等得到充分利用,工艺过程试剂消耗为零。同时,脱铜渣含铜可稳定控制在6%左右,并回收了部分Au、Ag物料,提高了Au、Ag的回收率。  相似文献   
22.
脉状黄铁矿床集中于鲁、浙、粤三省,其中伴生金、碲、硒等元素可以在黄铁矿中得到富集,研究了成矿规律,对综合利用工作提出了看法。  相似文献   
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In this work, we report the 2.05 μm emission and ∼3 μm broadband spectra of Ho2O3-doped 33GeO2–30TeO2–27PbO–10CaO (in mol%) glass under 640 nm laser excitation. Clear emission spectra due to the 5I75I8 transition and the 5I65I7 transition in Ho3+ are observed. The 2.05 μm emission intensity and the full width at half maximum (FWHM) of the ∼3 μm broadband depend on the Ho concentration. The peak stimulated emission cross-section of Ho3+ is 6.57 × 10−21 cm2 at 2.05 μm, as calculated by the McCumber theory. The emission spectra are recorded and the maximum emission intensity at 2.05 μm is obtained at a doping level of 0.5 mol% Ho2O3 in the glass. A broad and flat emission band from 2700 nm to 3050 nm is observed in 2 mol% Ho2O3-doped tellurium germanate glass. The lifetime of the 5I7 state decreases with the increase in Ho3+ concentration due to non-radiative relaxation processes. An energy transfer coefficient of 271.88 mol−1 s−1 is obtained.  相似文献   
25.
Tellurium tubular crystals were grown by direct thermal evaporation of tellurium metal in an inert atmosphere on quartz substrates at ambient pressure without employing any catalyst. Tellurium powder was evaporated by heating at 600 °C and was condensed at a substrate temperature of 300–350 °C in the downstream of argon gas at a flow rate of 100 mL/min. The structure and chemical composition of the as-synthesized samples were examined by X-ray diffraction analysis, scanning electron microscopy, energy-dispersive X-rays microanalysis and micro-Raman spectroscopy. Scanning electron microscopy images and X-ray diffraction patterns showed that the as-synthesized Te had a tubular single-crystalline morphology with a hexagonal cross-section. The Te microtubes were typically 0.5–6 mm long, 30–70 μm in external diameter, and 5–20 μm thick. NO2 gas-sensing properties of the Te microtubes at room temperature were also investigated. They showed a promising sensitivity and response towards tested gas.  相似文献   
26.
刘海英  王燕 《当代化工》2014,(9):1907-1908
地质样品经由硝酸、氢氟酸、高氯酸三酸溶解,用盐酸溶液提取溶解样品,加入一定量的铁盐用以掩蔽干扰。采用断续流动氢化物原子荧光光谱法测定样品中元素碲的含量,并且在试验过程中找出该方法测定碲元素的最佳条件。  相似文献   
27.
Ammonium trichloro[1,2-ethanediolato-O,O′]-tellurate (AS101) is the most important synthetic Te compound from the standpoint of its biological activity. It is a potent immunomodulator with a variety of potential therapeutic applications and antitumoral action in several preclinical and clinical studies. An experimental design has been used to develop and optimize a novel microwave-assisted synthesis (MAOS) of the AS101. In comparison to the results observed in the literature, refluxing Te(IV) chloride and ethylene glycol in acetonitrile (Method A), or by refluxing Te(IV) chloride and ammonium chloride in ethylene glycol (Method B), it was found that the developed methods in the present work are an effective alternative, because although performance slightly decreases compared to conventional procedures (75% vs. 79% by Method A, and 45% vs. 51% by Method B), reaction times decreased from 4 h to 30 min and from 4 h to 10 min, by Methods A and B respectively. MAOS is proving to be of value in the rapid synthesis of compounds with new and improved biological activities, specially based on the benefit of its shorter reaction times.  相似文献   
28.
Tellurium oxide-based glasses in the form of 75TeO2 – 10ZnO – (10-x)Nb2O5 – 5Li2O – xCe2O3; where x = 0.5, 1, 1.5, 2, 2.5 mol%, were prepared by using the melt-quenching method. X-Ray Diffraction pattern (XRD) detected the amorphous nature of all the prepared glasses. Physical properties like density (ρ), molar volume (Vm), and oxygen packing density (OPD), have been determined and calculated. Fourier transform infrared spectroscopy (FTIR) studies showed that the glass network contains TeO4, TeO3+1/TeO3, ZnO4, and NbO6 as structural units. The glass transition temperature (Tg), onset of glass crystallization temperature (Tx), crystallization temperature (Tc), and melting temperature (Tm) have been determined by using differential scanning calorimetry (DSC). The optical band gap (Eopt), the Urbach energy (?E), and the cut off wavelength (λc) were determined through the optical absorption data.  相似文献   
29.
This work describes the study of Te underpotential deposition on Pt in acid media using cyclic voltammetry, rotating ring-disc electrode and electrochemical quartz crystal microbalance techniques. The voltammetric results indicate the presence of two dissolution peaks in the positive scan with a total charge density of 420 μC cm−2. These phenomena are attributed to the deposition of one Te monolayer with the occupancy of two active Pt sites by each ad-atom. This is confirmed by rotating ring-disc electrode results. The electrochemical quartz crystal microbalance (EQCM) experiments yielded the small mass variation of −32 ng cm−2 (while the theoretical one is −140.4 ng cm−2 for a complete Te monolayer). This low value can be attributed to the simultaneous adsorption of water, perchlorate anions and the formation of platinum oxide.  相似文献   
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