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排序方式： 共有7211条查询结果，搜索用时 15 毫秒
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Dou G Holmes AS Yeatman EM Wright RV Kirby PB Yin C 《Advanced materials (Deerfield Beach, Fla.)》2011,23(10):1252-1256
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Zhang L Yu JC Mo M Wu L Kwong KW Li Q 《Small (Weinheim an der Bergstrasse, Germany)》2005,1(3):349-354
In this study we demonstrate that one-dimensional (1D) nanostructured lead telluride (PbTe) can be synthesized in a hydrothermal reaction between lead foil and tellurium powder. The resulting materials were characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The formation of the 1D structure can be explained by an in situ hydrothermal rolling-up mechanism whereby PbTe is formed hydrothermally and deposited on the lead substrate. The lead underneath the PbTe layer is then selectively etched by a cetyltrimethylammonium bromide solution, thus allowing the PbTe to roll up into 1D structures. This method can be extended to prepare other 1D tellurides, including CdTe, Cu(2)Te, and Ag(2)Te. 相似文献
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某钼铅多金属矿,有用矿物为辉钼矿、方铅矿和磁铁矿,脉石矿物为石英、方解石、长石、云母。针对辉钼矿与方解石相互包裹紧密连生,辉钼矿与方铅矿简单连生,黄铁矿包裹它形粒状方铅矿颗粒,少量方铅矿与辉钼矿连生等特点,采用钼铅混合浮选-钼铅分离的工艺流程,即将原矿磨细至75%-0.074 mm,经一次粗选、一次扫选、两次精选获得钼铅混合精矿,混合精矿再磨至80%-0.038 mm后,经一次粗选、两次扫选、四次精选获得钼精矿和铅精矿。小型闭路浮选试验获得钼精矿中钼品位为49.6%,铅精矿中铅品位为54.98%,钼、铅回收率分别为85.44%和85.83%。 相似文献
88.
The mechanisms of adsorption of cadmium(II), mercury(II) and lead(II) on to shredded rubber from old automobile types have been studied and it is shown that at least two distinct processes can be involved depending upon the metal being adsorbed. Mercury and cadmium uptake are accompanied by displacement of zinc and therefore probably involve an ion exchange type mechanism. Lead adsorption, in contrast, involves no zinc displacement and is not competitive with cadium or mercury uptake, suggesting that a completely separate mechanism and site of binding are used by lead(II). 相似文献
89.
The electroflotation of palm oil mill effluent (POME) using lead dioxide-coated titanium anode on a laboratory scale was described. The anode was found to be corrosion-resistant under the conditions of the experiment. The feasibility of the process was determined by monitoring the effluent quality as a function of electrolysis time. Simultaneous flotation of suspended particles and anodic destruction of soluble substances in POME were observed. About 40% of the COD of the dissolved substances of POME could be anodically destroyed together with 86% of suspended particles, made up of mainly plant cell debris, floated off. It is envisaged the electroflotation process could form the first stage of a treatment system with aerobic or physicochemical process as secondary treatment step. 相似文献
90.
A colorimetric method for the determination of arsenic in potable water was developed with a limit of detection of 0.0005 mg l−1. Arsenic(V) reacts quantitatively with potassium iodide in the presence of sulphuric acid and releases an equivalent amount of iodine, which imparts a pink colour to a carbon tetrachloride extract, this colour being measured at a predetermined wavelength of 515 nm. The method was used to differentiate between arsenic(V) and arsenic(III) and to analyse water samples from rivers, wells and lakes. No interference from arsenic(III), iron(III), chromium(VI) or lead(IV) was observed. 相似文献