933 resultados para Tin oxyhydroxide
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A novel organotin complex, EtPhSnCl(2) . 2HOC(10)H(6)CH = NC6H1OCH3 was synthesized, and its crystal structure was determined by X-ray diffraction method. The crystal is triclinic, belonging to space group,
with unit cell parameters a = 1.150 8(5) nm, b = 1. 153 1(5) gm, c = 1. 004 6 (3) nm, alpha = 94. 15 (3)degrees, beta = 115.47 (3)degrees, r = 85. 94 (4)degrees, V = 1199 7(1) nm(3), Z=2, D-c=1.68 g/cm(3), mu=13. 20 cm(-1), F(000)=618 for 4 131 reflections tions. R=0. 047, R(w)=0. 047. The ligand coordinates to tin atom via phenolic oxygen atom. The complex has a distored trigonal bipyramidal structure, the phenolic oxygen atom of the ligand and one of two chlorine atoms occupy the axial position. The distance between noncoodinated nitrogen atom with phenolic oxygen atom is 0. 257 4 nm, which indicates that the intramolecular hydrogen bond of Schiff base ligand is retained in the complex.
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The voltammetric behavior of cytochrome c entrapped in hydrogel membranes at paraffin wax-impregnated spectroscopic graphite electrodes (WISGE) was studied in this paper. A pair of well-defined peaks appeared at +70 mV (vs. Ag/AgCl). Beside these two peaks, another pair of peaks emerged at around +225 mV. Further investigations suggested that at least three states of cytochrome c existed in the membranes due to the special structure of the hydrogel. The native conformation of cytochrome c molecules was stabilized by the hydrophilic environment that was formed by the hydroxyl structure of the membranes and facilitated the cytochrome c electron transfer reaction at +70 mV. The molecules directly adsorbed on the surface of the graphite electrode were responsible for the redox peaks at around +225 mV. Whether the adsorption peaks were detectable or not was related to the thickness of membranes and the pre-retaining time before the formation of membranes.
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The synthesis and properties of the title complex CH3OCOCH2CH2SnCl3.2-HOC6H4CH=NC6H4-3'-CH3 are described. It crystallizes from benzene in the monoclinic space group P2(1/n) with unit cell dimensions a=10.326 (C),b=6.815(8), c=12.931(6) Angstrom, beta =111.52(3,)degrees, V=2088.7(1) Angstrom (3), Z=4, F(000) =1040, mu =16.31 cm(-1), Dc=1. 67g/cm(3) final R factor is 0.037 for 3177 observed reflections, 1 greater than or equal to3 sigma (1(0)). The tin atom in the structure of the complex exists in a distored octahedral geometry defined by three Cl atoms, the C and O atoms of a chelating methoxycarbonylethyl. group as well as an O atom derived from the Schiff base ligand.
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The title complex was synthesized and characterized by H-1, C-13, Sn-119 NMR and IR spectra. A single crystal X-ray diffraction study confirmed its molecular structure and revealed that 3,4,5-trimethoxy-benzoyl salicylahydrazone was a tridentate and approximately planar ligand. The complex crystallizes in the triclinic space group P1BAR with a = 9.208(3), b = 12.536(2), c = 12.187(4) angstrom, alpha = 113.12(2), beta = 90.58(2), gamma = 81.42(2), V = 1277.5(6) angstrom, Z = 2. The structure was refined to R = 0.033 and R(w) = 0.041 for 3944 observed independent reflections. The tin atom has a distorted trigonal bipyramidal coordination. The Sn-C bond lengths are 2.129(5) and 2.113(5) angstrom (av. 2.121(5) angstrom), the C-Sn-C angle is 123.3(2); the bond length between the tin atom and the chelating nitrogen is 2.173(3) angstrom. Two chain carbon atoms and the chelating nitrogen atom occupy the basal plane. The skeleton of two erect oxygen atoms and the tin atom is bent (O-Sn-O angle = 153.5(1)). In the complex, the ligand exists in the enol-form.
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The behaviour of the electroplated copper film electrode on tin oxide/glass or glassy carbon surface was studied in potassium hydroxide medium by cyclic voltammetry and in situ transmission spectroelectrochemistry. The results indicate that the electroplated copper film electrode is similar to a copper electrode and cyclic voltammetry with this electrode affords more resolution. The anodic peaks were found to correspond successively to the adsorption of oxygen, the formation of a surface layer of Cu2O, the formation of a surface layer of Cu(OH)2 or CuO and formation of a thick multilayer film of CuO. This is the first time it has been proposed that a surface layer of Cu(OH)2 or CuO is formed from the oxidation of the surface layer of Cu2O. Similarly, a clear interpretation is presented that the cathodic peaks correspond successively to the reduction of CuO to Cu2O, the reductions of Cu2O to Cu and the soluble Cu(II) species to Cu. On the other hand, a shoulder peak related to the chemical transformation of Cu(OH)2 to CuO was first observed.
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The present work is devoted to the studies on relationship of structure and activity of Sn-Mo oxides by using XRD, ESR, IR, XPS, TEM and SEM. Eight samples with Mo/(Mo + Sn) rations: 0.0, 0.1, 0.2, 0.4, 0.6, 0.8, 0.9, 1.0 were prepared. On the basis of structure characterization, Sn-Mo oxides can be divided into three groups: Catalysts I with Mo/(Mo + So) less-than-or-equal-to 0.2, Catalysts II with 0.2 < Mo/(Mo + Sn) < 0.8, and catalysts III with Mo/(Mo + Sn) greater-than-or-equal-to 0.8. The solid solution of Mo5+ in tin oxide was formed and the cation vacancy was formed in catalysts I. The solid solution of Sn4+ in molybdenum oxide was formed in catalysts III. The lattice oxygen in catalysts III has higher mobility and reactivity than that in catalysts I. The catalysts III showed higher activity but lower selectivity than that of catalysts I.
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The mineralogical and geochemical characteristics of Fe-oxyhydroxide samples from one dredge station (long. 103 degrees 54.48'W, lat. 12 degrees 42.30'N, water depth 2655 m) on the East Pacific Rise near lat 13 degrees N were analyzed by XRD, ICP-AES, and ICP-MS. Most Fe-oxyhydroxides are amorphous, with a few sphalerite microlites. In comparison with Fe-oxyhydroxides from other fields, the variable ranges in the chemical composition of Fe-oxyhydroxide samples are very narrow; their Fe, Si, and Mn contents were 39.90%, 8.92%, and 1.59%, respectively; they have high Cu (0.88%-1.85%) and Co (65x10(-6)-704x10(-6)) contents, and contain Co+Cu+Zn+Ni > 1.01%. The trace-element (As, Co, Ni, Cu, Zn, Ba, Sr) and major-element (Fe, Ca, Al, Mg) contents of these samples are in the range of hydrothermal sulfide from the East Pacific Rise near 13 degrees N, reflecting that this type of Fe-oxyhydroxide constitutes a secondary oxidation product of hydrothermal sulfide. The Fe-oxyhydroxide samples from one dredge station on the East Pacific Rise near 13 degrees N are lower in Sigma REE (5.44x10(-6)-17.01x10(-6)), with a distinct negative Ce anomaly (0.12-0.28). The Fe-oxyhydroxide samples have similar chondrite-normalized rare-earth-element (REE) patterns to that of seawater, and they are very different from the REE composition characteristics of hydrothermal plume particles and hydrothermal fluids, showing that the REEs of Fe-oxyhydroxide are a major constituent of seawater and that the Fe-oxyhydroxides can become a sink of REE from seawater. The quick settling of hydrothermal plume particles resulted in the lower REE content and higher Mn content of these Fe-oxyhydroxides, which are captured in part of the V and P from seawater by adsorption. The Fe-oxyhydroxides from one dredge station on the East Pacific Rise near 13 degrees N were formed by secondary oxidation in a low temperature, oxygenated environment. In comparison with the elemental (Zn, Cd, Pb, Fe, Co, Cu) average content of hydrothermal sulfide samples from the East Pacific Rise near 13 degrees N, the Zn, Cd, and Pb contents of the Fe-oxyhydroxides are lower, and their Fe, Co, and Cu contents are higher.
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本文利用ICP-AES、EPMA、X-ray衍射等测试技术以及聚类分析和因子分析等多种数理统计方法,系统地对中太平洋海区富钴结壳的元素地球化学特征、矿物组成和微观组构进行了研究,并探讨了其成因机制,获得以下主要认识: 1中太平洋海区富钴结壳类型多样,均为水成成因,其矿物相主要由锰矿物相、铁矿物相和非金属矿物相组成;富钴结壳壳层发育多种原生和次生构造类型。 2磷酸盐化作用不仅强烈改变富钴结壳元素初始含量,而且造成富钴结壳某些元素间的相关性发生改变,这些敏感型元素对可用于指示富钴结壳是否发生磷酸盐化。在不同水深段内,未磷酸盐化型富钴结壳的主要元素随经向、纬向的变化趋势相似,表明其受水体化学障、表面生产力和物质来源等环境参数控制;而随水深的变化则具有区域一致性,表明水体化学具有区域成层性。 3未磷酸盐化富钴结壳稀土元素含量和轻重稀土分馏程度随水深发生规律变化,这种变化不仅与它们在海洋中的含量和行为有关,也与海洋背景颗粒的吸附有关;铈(Ce)在富钴结壳中基本上呈4价,且动力学因素控制了其富集过程,因此Ce异常不能用于指示富钴结壳形成环境的氧化程度。 4基于富钴结壳微层呈锯齿状且同一微层生长速率不同,提出了富钴结壳在各种基底表面生长以及后继发育过程受固液界面双电层控制的发育模式。在富钴结壳整个发育过程中,经历了从贫氧环境向富氧环境的转变,但微环境则呈富氧-低氧过程的交替。 关键词: 富钴结壳;中太平洋;元素地球化学;界面双电层
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有害赤潮(Harmful algal blooms, HAB)已成为全球性的海洋灾害,对我国近海养殖业危害尤为巨大,研究赤潮发生、发展的主要环境影响因子,对于控制赤潮的发生以及加强赤潮的防治具有十分重要的意义。本文根据国家自然科学基金“九五”重大项目“中国沿海典型增养殖区有害赤潮发生动力学防治对策研究”项目组近年来对胶州湾东北部养殖海域的监测资料,分析了该海区营养状况,结合该区自然环境特点,探讨了发生于1998年7月和1999年6月两次硅藻赤潮的主要影响因子;并应用胶州现场海水进行了室内模拟培养实验,对影响有害赤潮生消过程的关键环境因子进行了分析探讨。对1998和1999年赤潮多发季节胶州湾东北部增养殖水域海水的营养状况进行了分析,并参照潜在性富营养化的概念,应用NQI指数对该海域的富营养化水平进行了评价。结果表明:(1)胶州湾东北部增养殖海域赤潮多发季节TIN、DIP和活性硅酸盐的含量均较高,远高于同期胶州湾大面观测站各营养盐的平均含量;该海域有机污染物含量相对营养盐含量不高。(2)该海域春季氮、磷营养盐含量充足,水域属富营养化平;夏季该海域具有较高的生物具,磷酸盐水平相对较低,海域多数时间属于磷限制潜在性富营养化水平;但这种限制极易为外界补充所改变,如陆源输入、养殖废水的排放等。(3)该海域为典型增养殖区,养殖废水对海域营养盐的补充有重要意义,因此应当加强对该海域养殖业的综合管理。对分别于1998年7月和1999年6月在胶州湾东北部增养殖海域发生的中肋骨条藻(Skeletonema costatum)赤潮和浮动弯角藻(Eucampia zoodiacus)赤潮生消过程中环境因子的变化进行了探讨。发生赤潮生物量的升高常伴随海水pH值、溶解氧(DO)含量的升高以及各营养盐(氮、磷、硅)含量的降低;认为在该海域较高营养盐含量和较高生物量的情况下,赤潮发生前大规模的降雨过程及随后的气候条件为赤潮生物的快速生长繁殖创造了有利条件;无机磷和活性硅酸盐含量相对于无机氮显得较低,对该海域硅藻赤潮的生消过程起着控制作用。采集胶州湾现场海水进行了实验室模拟培养实验,对影响赤潮生消过程的主要环境因素进行了研究和探讨。结果表明,现场海水进行模拟培养时,排除了潮流、风以及水团间交流混合等因素对水体中浮游生物的影响,培养水体中的浮游植物生物量都存在增高的现象;在氮、磷、硅等营养盐含量充足的条件下,浮游植物可快速进入指数增长期,并较快发展形成赤潮,高浓度的营养盐常导致培养水体中浮游植物的较高的生长速率,浮游植物对氮磷营养盐的吸收受到环境中营养盐含量的影响;初始环境下营养盐的限制可抑制浮游植物的进一步增殖,发生赤潮水体中某种营养盐的含量降低最终导致了赤潮的消亡。
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Eleven species of the caridean family Crangonidae are reported from the material collected by the Philippine PANGLAO 2004 and PANGLAO 2005 expeditions. Although they have been reported from the Philippines before, all the species have their colouration described and illustrated here for the first time.
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Ten species belonging to three genera of the subfamily Pontoniinae were colleted by the deep-sea expedition "PANGLAO 2005" in the Philippines, including four new species of the genus Periclimenes, i.e., P. boucheti n. sp., P. leptunguis n. sp., P. ngi n. sp., and P. panglaonis sp. nov., and one newly recorded species from the Philippines, Periclimenes laccadivensis. They are reported with color photographs except one species, Plesiopontonia monodi. The possible synonymy of Periclimenes foresti and P. granuloides is discussed.
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Muanggang-Dajing area located in the south end of Dahinggan Mts is the only discovered tin-polymetallic minerzalization belt and the only tectonic magmaism zone with middle-upper grade tin-ore deposites in North China. Tin mineralization in this area is believed tn related to Yanshannian granites which is different from those in South China tin belt. Through geochemical study of these granites on the base of fieldworks , thin section observation, major and trace elements as well as isotopic composision determination, the isochronic sequence and petrogenetic series for the granites have been determined. Hi light ing on the petrogenesis of earlier Yanshannian of MOmarh granites, two groups granites with different Neodymium isotopic features have been distinguished. Both belonging to hi-K calc-alkalinic series, their nature of source rocks and.magma processing were restricted, we argue for that the two groups have get the isotopic differences from their sources-middle and later proterozoic juvenial crustal via mantle underplating. From then on , there is a pre-enrichment of tin in this area. The partial melting from a F rich soruses can dissolve and carry more tin from the same some due to the de-connection of melt, which supply the mineralization fluids after a thoroughly evolement.
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锡的分布和成矿作用通常与花岗岩浆作用具有十分密切的联系。以往研究表明锡矿化与高度分异的S型花岗岩或陆壳改造型花岗岩具有密切的成因联系,但近年来随着大量与A型花岗岩有关的锡矿床的发现,人们开始关注A型花岗岩与锡成矿关系的研究。相对于与S型花岗岩有关的锡矿床来说,与A型花岗岩有关的锡矿床成成矿机理的研究积累少,研究程度相对较低。 湘南地区位于南岭多金属成矿带中部,是我国华南地区重要的有色金属成矿带。近年来在该成矿带上新发现的芙蓉超大型锡多金属矿床为世界瞩目,该矿床的形成与骑田岭花岗岩具有密切的时空关系。近年来研究显示骑田岭花岗岩具有A型花岗岩的特征。本文以芙蓉超大型锡多金属矿床和相关的骑田岭岩体为研究对象,在前人研究的基础上,运用岩石学、矿物学、流体包裹体、微量元素和稳定同位素地球化学等理论和方法,对芙蓉锡矿成矿流体的地球化学特征及其演化机制进行了系统的研究,并在此基础上探讨了骑田岭花岗岩体与芙蓉锡矿间的成因联系和芙蓉锡矿的成因机制。论文取得的主要认识包括以下几个方面: 1. 运用矿物学、岩石化学、微量元素地球化学以及同位素地球化学方法,进一步证实了骑田岭花岗岩体具有A型花岗岩的特征,总体具有偏铝质-弱过铝质、高硅富碱高钾的地球化学特征,早晚两期花岗岩具有同源岩浆演化特征,属于A2型花岗岩。同位素地球化学数据显示花岗岩体具有EMII型富集地幔的特征,形成于华南大陆地壳拉张减薄的构造环境,成岩过程中有地幔物质加入。 2. 通过对矿石矿物组构和成分的岩矿鉴定、扫描电镜和电子探针分析,确定了芙蓉锡多金属矿床原生夕卡岩形成于较氧化的环境,成岩作用主要与早期侵入的角闪石黑云母花岗岩密切相关,锡主要以Sn(IV)进入夕卡岩的造岩矿物晶体内。退蚀变夕卡岩、云英岩和蚀变花岗岩矿化为锡成矿主阶段,三种矿化类型的成矿流体具有相似的地球化学性质,即富Cl、Ti和Sn的特征,而锡石硫化物型矿石形成于成矿晚阶段。 3. 运用流体包裹体地球化学理论和方法以及激光拉曼分析技术,揭示了芙蓉锡矿的成矿流体组成、形成的物理化学条件和演化特征。芙蓉锡多金属矿田成矿流体为CO2-CH4-CaCl2- NaCl-KCl不混溶体系,成矿过程中发生流体不混溶作用。芙蓉锡矿成矿流体盐度为0~50.63 wt%NaCl eq.,密度为0.31~1.12g/cm3,主成矿阶段热液流体的均一温度主要集中在300-450℃,流体压力为179-1800bar,成矿晚阶段锡石硫化物型矿石中均一温度主要集中在150~300℃,流体压力为400-600bar。成矿流体特别是主成矿阶段的流体成矿过程中普遍发生了沸腾现象。从主成矿阶段到成矿晚阶段、矿化期后,热液流体盐度呈降低的趋势,流体成分也从含CO2、CH4的CaCl2-NaCl-KCl-H2O水溶液体系转化为不含CO2的简单NaCl-KCl-H2O水溶液体系。 4. 通过分析主要矿化类型矿石中脉石矿物的稀土元素和稳定同位素特征,揭示了成矿流体来源。研究表明芙蓉矿床成矿期热液脉石矿物的稀土元素地球化学和稳定同位素地球化学显示了与本区花岗岩具明显的相似性,骑田岭黑云母花岗岩形成过程中分异出的岩浆期后热液应是芙蓉矿床成矿流体的主要来源,成矿过程中有少量经过深循环的大气降水加入。 5. 在总结前人研究成果的基础上,综合上述研究,探讨了骑田岭花岗岩体与芙蓉锡矿间的成因联系和芙蓉锡矿的成因机制。本文认为骑田岭岩体中黑云母花岗岩与Sn成矿具有密切的成因联系,芙蓉锡矿田的成矿流体主要来源于黑云母花岗岩岩浆结晶期后分异出的富Cl和Sn的热液流体。芙蓉锡矿成矿流体中锡主要呈Sn(II)与氯离子形成亚锡氯络合物进行迁移,低温的大气降水与高温的岩浆热液流体混合,导致流体体系温度、盐度、压力的降低和富CO2相流体的分离(CO2去气作用),流体的氧逸度升高,使得Sn(II)与氯离子形成亚锡氯络合物解体,Sn(II)被氧化成SnO2并发生沉淀作用。这种流体的混合作用是导致锡石沉淀的最有效的机制。
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华南地区中生代地壳拉张、岩石圈伸展减薄与大规模成岩成矿作用的时代分布格局和地球动力学背景一直是国内外关注的重要科学问题。富碱侵入岩及其有关的成矿作用是伸展构造的直接表现之一。近年来的研究发现,南岭中段花山-西山-香花岭-骑田岭NE向的花岗岩带为一中晚侏罗世形成的具有高εNd(t)和低Nd模式年龄的富碱侵入岩带,并伴有大规模的钨锡多金属成矿作用,是研究大规模地壳拉张、岩石圈伸展减薄与该区大规模的钨锡多金属成矿作用的耦合关系及其深部动力学机制的理想对象。本文以香花岭地区花岗岩及其有关的钨锡多金属矿床为研究对象,运用岩石学、元素地球化学、同位素地球化学等方法手段,对香花岭矿区花岗岩的成因和形成构造环境、成矿物质与成矿流体的来源、成矿年代学及成岩成矿的地球动力学背景等方面进行了系统研究,并初步建立了该矿的成矿模式。论文主要获得以下认识: (1)通过对香花岭矿区癞子岭和尖峰岭岩体的主、微量元素及Sr、Nd同位素研究,查明上述两个岩体均具有高硅、富碱及成矿元素,富LILE及Zr、Ga等部分高场强元素(HFSE),贫Ca、Mg,P,Eu,较高的εNd及较低的Nd模式年龄等特征,具有相同的岩浆源区,属于后造山背景下形成的铝质A型花岗岩(A2型),具有壳、幔混合来源。 (2)利用白云母Ar-Ar同位素定年手段对香花岭锡多金属矿床、香花铺钨多金属矿床及尖峰岭云英岩型锡多金属矿床进行了成矿年代学研究,并首次对该矿的矿石矿物-锡石进行了U-Pb同位素定年。结果表明,香花岭地区钨锡多金属矿床的成矿时限为154-161 Ma,与矿区花岗岩黑云母K-Ar年龄相一致,并与区域主要钨锡矿床的形成时间一致。 (3)微量元素、稀土元素及同位素地球化学的研究表明,香花岭锡多金属矿床与矿区花岗岩具有密切的成因联系,矿区花岗岩不仅为该区成矿作用提供热动力和介质条件,而且为成矿作用提供了主要的物源。此外,矿区内的赋矿地层可能提供了部分成矿物质。早期成矿流体以岩浆水为主,晚期有大量大气降水的加入。 (4)对香花岭锡多金属矿床锡的超常富集机制作了初步探讨,认为该区锡的超常富集可能归功于如下几个因素:首先,富含F等挥发分的花岗岩浆高度分异演化出富含挥发分及成矿元素的超临界流体,成矿流体在流经赋矿地层时萃取了其中的部分成矿元素;其次,伴随着围压的不断降低,成矿流体发生了沸腾及连续的去气作用,导致了成矿流体的高度浓缩,当流体达到饱和或过饱和时,成矿元素沉淀成矿;最后,早期形成的矿床进一步受到后期的叠加改造,从而形成该区高品位的锡矿石。 (5)根据上述研究,香花岭锡多金属矿床与矿区花岗岩具有密切的时间、空间及成因联系,二者应为同一构造背景下形成的产物。结合区域上的研究,香花岭矿区的成岩成矿作用与南岭中段同时代的其他钨锡多金属矿床具有相同的地球动力学背景。这种构造背景可能与该区中-晚侏罗世构造体制转换,地壳拉张-岩石圈伸展减薄背景下,软流圈地幔上涌及发生壳、幔相互作用密切相关。 (6)初步建立了香花岭锡多金属矿床的成因模式:在该区中晚侏罗世大规模地壳拉张、岩石圈伸展减薄背景下,地幔物质上涌到中下地壳,发生壳幔相互作用,形成壳幔混合的花岗岩浆。花岗岩浆经充分分异演化,形成富含挥发分和成矿元素的一种具超临界性质的成矿流体。成矿流体在上升过程中随着围压的不断降低,发生了连续的去气作用,使得成矿流体高度浓缩并沿有利的构造部位成矿,并在后期受到改造、叠加等成矿作用,以至于形成了该区最富的锡矿床。
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柿竹园有色金属矿山是我国已经探明的地质资源储量最大的钨、钼、锡、铋等多金属矿山,其中锡累计探明储量达48万吨。目前柿竹园仅回收钨、铋、钼、铅、锌、萤石矿等,大量锡随着钨、钼、铋等金属的开采作为废料进入尾矿,因此在尾砂库中保留了丰富的锡资源。对柿竹园尾矿中锡进行回收再利用,必须首先对其综合回收利用途径与前景作出科学评价。本文对柿竹园多金属矿床Ⅲ矿带锡的赋存形式、千吨尾矿库尾矿物质组成特征、锡的丰度、赋存形式和分布进行了研究,在此基础上分析柿竹园尾砂锡综合回收利用的前景。