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61.
The electrochemical treatment of solutions containing C.I. Basic Yellow 2 (BY2) in aqueous solutions with carbon-PTFE (polytetrafluoroethylene) and carbon nanotube (CNT)-PTFE electrodes as cathode has been studied. The fabricated electrodes were characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The amount of electrogenerated H2O2 on the surface of these electrodes was investigated, too. The results showed that the amount of H2O2 obtained with the CNT-PTFE electrode was nearly three times higher than that of carbon-PTFE electrode. The decolorization efficiency of BY2 in peroxi-coagulation process reached 62% and 96% in the first 10 min by carbon-PTFE and CNT-PTFE electrodes at 100 mA, respectively. The effect of operational parameters such as applied current, initial pH and initial dye concentration was studied in an attempt to reach higher decolorization efficiency. The degradation and mineralization of BY2 using CNT-PTFE electrode were followed by total organic carbon (TOC) and GC–MS analysis. The results of TOC measurements indicated that peroxi-coagulation with carbon-PTFE allowed 81% mineralization after 6 h of electrolysis; whereas peroxi-coagulation with CNT-PTFE yields 92% mineralization under the same conditions. GC–MS analysis verified the identity of intermediates and a reaction pathway based on them was proposed.  相似文献   
62.
本文系统收集整理了云南省东南部新寨锡矿资源勘查过程中形成的85个探矿工程编录资料,建立了三维空间数据库,对具有空间属性的锡品位数据进行了基本统计分析和矿化趋势分析,并绘制了矿化等值线图和矿化趋势图,认为新寨矿区矿化富集带走向与矿化趋势等值线走向均与地层走向方向一致,显示出赋矿地层对锡的富集具有明显的控制作用;矿区南东浅部矿化富集带较北西深部矿化富集带锡矿化强度高,总体矿化趋势北西低南东高,结合地质背景推测矿区发育的向斜挠曲构造影响了锡的富集,远离向斜轴部锡品位有增强趋势。  相似文献   
63.
五龙沟金矿是青海省东昆仑成矿带最具找矿潜力的矿床。在搜集五龙沟地区金多金属矿床成矿大地构造背景、区域地层、岩性、构造、岩浆岩等方面资料的基础上,首先对区内典型金多金属矿床地质特征分别进行了描述,然后从地层、岩浆岩、构造等方面对区内金多金属矿床的控矿因素进行了系统分析,最后从矿床成矿时间、空间分布及成因等方面对成矿规律进行了总结。结果表明:①五龙沟地区金多金属矿床产于构造韧性剪切带中,受构造及其演化控制明显;②金矿床在时间上具有多阶段性和长期性的分布规律,在空间上严格沿3条韧性、脆-韧性剪切带分布,各剪切带内矿床具有等距性和平行性的分布特点;③多金属矿床多分布于剪切带与后期NE-SW向的断裂带交汇部位,往往成群成组分布;④金矿体形成于多金属矿之前,以深部岩浆为主的壳幔混源、壳源是金多金属矿的重要成矿物质来源,伴随构造演化使成矿物质进一步活化并富集形成金多金属矿体。上述研究成果对于区内进一步开展金多金属矿、构造热液蚀变型矿床的找矿工作具有一定的参考价值。  相似文献   
64.
Degradation of a synthetic azo dye, Orange II, by electro-peroxone (E-peroxone) treatment was investigated. During the E-peroxone process, ozone generator effluent (O2 and O3 gas mixture) was continuously sparged into an electrolysis reactor, which was equipped with a carbon-polytetrafluorethylene (carbon-PTFE) cathode to electrochemically convert the sparged O2 to H2O2. The in-situ generated H2O2 then reacted with the sparged O3 to produce •OH, which can oxidize ozone-refractory organic pollutants effectively. Thus, by simply combining conventional ozonation and electrolysis processes, and using a cathode that can effectively convert O2 to H2O2, the E-peroxone process degraded Orange II much more effectively than the two processes individually. Complete decolorization and 95.7% total organic carbon (TOC) mineralization were obtained after 4 and 45 min of the E-peroxone treatment, respectively. In comparison, only 55.6 and 15.3% TOC were mineralized after 90 min of the individual ozonation and electrolysis treatments, respectively. In addition to its high efficiency, the E-peroxone process was effective over a wide range of pH (3–10) and did not produce any secondary pollutants. The E-peroxone process can thus provide an effective and environmentally-friendly alternative for wastewater treatment.  相似文献   
65.
曲溪金矿床冷家溪群地层初始具有较高的含金背景值,由于变质和构造作用,易释放出金并活化迁移,在局部沉淀富集。燕山早期由于陆内俯冲碰撞挤压作用,构造热事件致使深部的冷家溪群地层重熔或同熔形成花岗岩浆。岩浆发生底侵作用,沿深大断裂上侵,在上侵过程中,深部流体混入变质水和大气降水,并萃取了冷家溪群地层中金等成矿物质,携金热液迁移至构造有利部位卸载富集成矿。曲溪金矿床成矿过程中冷家溪群地层为成矿提供了金物质来源。花岗岩不但提供金物质来源,而且为成矿提供热动力。  相似文献   
66.
采用室内恒温好气培养试验,研究不同C/N有机物料腐解过程中有机磷的矿化特征与进程。结果表明:新鲜粪肥类有机物料中磷以无机磷(P i)为主,秸秆类有机物料中磷以有机磷(Po)为主,有机物料中有机磷在培养的前30天矿化最快,之后趋于平缓,培养结束时,供试有机物料中磷均以无机磷为主,约占全磷的70~90%;不同有机物料有机磷的残留率在腐解前期差别很大,后期趋于一致,有机磷的矿化要先于有机氮;有机物料中磷的矿化速率大小与C/PO及有机磷含量的大小存在显著的相关关系。  相似文献   
67.
New strategies for sludge stabilization and mineralization need to be developed since the use of sludge in agriculture is debatable and sludge incineration cannot be a systematic solution. Minimization of sludge production should be preferred. In this work, the effect of ozone on activated sludge solubilization and mineralization during batch experiments is assessed by establishing carbon and ozone mass balances. After extended ozonation of the sludge, more than 90% of the particulate carbon is modified. Depending on the experimental conditions, from 15 to 50% is found in a soluble form and from 35% to 95% was mineralized. The VSS/SS ratio decreases from 86% to less than 50% illustrating the sludge mineralization. The initial rate of ozone consumption by the sludge is very high (estimated value: 30 mgO3/g VSS.min) and corresponds to high rates of carbon solubilization and mineralization. More than 50% of the carbon obtained after ozonation is found to be readily biodegradable using a short-term BOD procedure.  相似文献   
68.
Based on chelation effect between iron ions and amino groups of chitosan, in situ mineralization of magnetite nanoparticles in chitosan hydrogel under ambient conditions was proposed. The chelation effect between iron ions and amino groups in CS–Fe complex, which led to that chitosan hydrogel exerted a crucial control on the magnetite mineralization, was proved by X-ray photoelectron spectrum. The composition, morphology and size of the mineralized magnetite nanoparticles were characterized by X-ray diffraction, Raman spectroscopy, transmission electron microscopy and thermal gravity. The mineralized nanoparticles were nonstoichiometric magnetite with a unit formula of Fe2.85O4 and coated by a thin layer of chitosan. The mineralized magnetite nanoparticles with mean diameter of 13 nm dispersed in chitosan hydrogel uniformly. Magnetization measurement indicated that superparamagnetism behavior was exhibited. These magnetite nanoparticles mineralized in chitosan hydrogel have potential applications in the field of biotechnology. Moreover, this method can also be used to synthesize other kinds of inorganic nanoparticles, such as ZnO, Fe2O3 and hydroxyapatite.  相似文献   
69.
冀西石湖金矿成矿地质特征   总被引:4,自引:5,他引:4       下载免费PDF全文
以幔枝构造成矿理论为指导,根据石湖金矿的地质特征、成矿物质来源、矿石品位变化、成矿控矿构造分析,指出石湖金矿区深部及外围均具较大找矿潜力。  相似文献   
70.
采用培育试验研究了红壤与潮土两个长期定位试验中不同处理小区表层土壤的矿化和硝化作用特征。结果表明:红壤的矿化作用和硝化作用都很弱,而潮土硝化作用非常强烈。采用适宜的施肥措施培肥后氮素的矿化和硝化速率都有很大的提高;pH是影响硝化作用的重要因素之一,硝化速率与土壤pH呈显著正相关。合理施用肥料调控土壤肥力是提高红壤和潮土肥力的重要措施。  相似文献   
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