20 resultados para 13077-023


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合成了三茚基稀土配合物(η~5-C_9H_7)_3Ln·OC_4H_8(Ln=Nd、Gd、Er),经元素分析、红外光谱、水解产物核磁共振谱及质谱表征,并测得了(η~5-C_9H_7)_3Nd·OC_4H_8(1)及(η~5-C_9H_7)_3Gd·OC_4H_8(2)的晶体结构。(1)、(2)均属六方晶系,P6_3空间群,Z=2。(1)的晶体学参数为a=b=1.1843(3)nm,c=1.0304(4)nm,V=1.25165(87)nm~3,D_c=1.49g·cm~(-3),最后一致性因子R=0.049;(2)的晶体学参数a=b=1.1805(2)nm,c=1.0236(2)nm,V=1.23536(56)nm~3,D_c=1.54 g·cm~(-3),R=0.023。平均Nd-C=0.2812nm,Gd-C=0.2795nm;Nd-O=0.2557(21)nm,Gd—O=0.2459(13)nm。配合物中四氢呋喃的四个碳原子处于完全无序状态。

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The complexes named in the title (eta-5-C9H7)3Ln.OC4H8 (Ln = Nd, Gd, Er) were synthesized by the reaction of anhydrous lanthanide trichlorides with indenyl potassium and cyclooctadienyl potassium (1:2:1 molar ratio) in THF. The complexes were characterized by elemental analysis, infrared and H-1-NMR spectroscopy, and mass spectrometry. In addition, the crystal structures of (eta-5-C9H7)3Nd.OC4H8 (1) and (eta-5-C9H7)3Gd.OC4H8 (2) were determined by an X-ray diffraction study. Complexes 1 and 2 belong to hexagonal space group P6(3) with unit cell parameters a = b = 11.843(3), c = 10.304(4) angstrom, V = 1251.7(9) angstrom-3, D(c) = 1.49 g.cm-3, Z = 2 for 1, and a = b = 11.805(2), c = 10.236(2) angstrom, V = 1235.4(6) angstrom-3 D(c) = 1.54 g.cm-3, Z = 2 for 2. The structures were solved by Patterson and Fourier techniques and refined by least-squares to final discrepancy indices of R = 0.049, R(w) = 0.053 using 925 independent reflections with I greater-than-or-equal-to 3-sigma(I) for 1, and R = 0.023, R(w) = 0.025 using 1327 independent reflections with I greater-than-or-equal-to 3-sigma(I) for 2. Coordination numbers for Nd3+ and Gd3+ are 10; the average bond lengths Nd-O and Gd-O are 2.557(21) and 2.459(13) angstrom, respectively. The structural studies showed the complexes to have 3-fold symmetry, but the THF molecule has no such symmetry; consequently the arrangement of carbon atoms in the THF molecule are disordered.

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Located in the Paleozoic uplift along the southern margin of Tu-Ha basin in eastern Xinjiang, the newly discovered Hongshan Cu-Au deposit occurs in the superimposed Mesozoic volcanic basin upon the north section of later Paleozoic Dananhu-Tousuquan accretionary arc. Kalatage Cu-Au orebelt is controlled by NWW-trend faults, and includes Hongshan and Meiling Cu-Au deposits. The host rocks of Hongshan ore district are mainly rhyolitic-dacitic ignimbrites, whereas Cu-Au mineralization is closely related to quartz porphyry, rhyolitic porphyry and granitic porphyry. Mineralization styles are dominantly veinlet-disseminated and veinlet, occasionally stockwork. The mineral association is chalcopyrite, pyrite, bornite, chalcocite and sphalerite. The hydrothermal alteration consists of silicfication, sericitization, alunitization, pyrophylitization, illitization, hydromuscovitization, and chloritization. Hongshan Cu-Au deposit, on the edge of the desert, is one of the driest areas in eastrn Tianshan. Moreover, the highest temperature has been up to 60℃, and the average rainfall receives only 34.1mm/y. The light rainfall and rapid evaporation in the vicinity of this deposit have allowed the formation of a great variety of water-soluble sulfates. Oxidization zone of this deposit lies on the upper part of primary sulfide orebodies appearing with a depth of 50-60m, which is dominant in sulfate minerals. 1. Based on the field observation, the volcanic and sub-volcanic rock composition, hydrothermal alteration, ore structure and mineralization characteristics, this paper proposed that the Hongshan Cu-Au deposit belongs to a transitional type from high-sulfide epithermal to porphyry Cu-Au deposit, which corresponds with the typical HS-epithermal deposit such as Zijinshan Au-Cu deposit in Fujian Province, SE-China. 2. The Hongshan copper-gold deposit was controlled by the tectonic, stratum, magma activity and volcanic apparatus, whereas Au mineralization is closely related to quartz porphyry, rhyolitic porphyry and fine grained pyritization in hydrothermal activity, and Cu mineralization is closely related to quartz porphyry and hydrothermal explosive breccia. 3. Oxidation zone of Hongshan Cu-Au deposit lies on the upper part of primary sulfide orebodies deposit. 23 sulfate minerals were identified in this work. The results of samples XRD and chemical analysis were furthermore confirmed through thermal, infrared spectrum and mössbauer spectrum analysis. Among those, nine minerals as Ferricopiapite, Cuprocopiapite, Rhomboclase, Parabutlerite, Krausite, Yavapaiite, Metasideronatrite Kroehnkite and Paracoquimbite were founded in China for the first time. And Paracoquimbite was secondly reported in the world (first case reported at 1938 in Chile). 4. EPMA analysis shows that Al impurity in crystal lattice is important to polytype formation of paracoquimbite and coquimbite besides stack fault. 5. Compared with Meiling Cu-Au deposit in the same Kalatage ore belt from the characteristics of δ34S of barite, lithofacies, hydrothermal alteration and homogeneous temperature, Hongshan Cu-Au deposit belongs to the same metallogenic system of HS-epithermal type as Meiling Cu-Au deposit. But Hongshan Cu-Au deposit has less extensive alteration and shallower denudation. 6. Sulfur isotope analyses show that δ34S values of pyrites vary in the range of +1.86‰~+5.69‰, with an average of 3.70‰, mostly in the range of +1.86‰~+3.20‰, and δ34Scp<δ34Spy. Therefore ore-forming fluid of porphyry comes from mantle and was contaminated by the earth’s crust. Sulfur isotope has reached balance in ore-forming process. 7. Sulfur isotope analyses show that δ34S values of sulfates vary in the range of +2.15‰~+6.73‰, with an average of +3.74‰, mostly equals as δ34S values of primary sulfides in Hongshan Cu-Au deposit. So supergene sulfates inherit sulfur of primary sulfide. δ34S values are mostly same in different sulfates. As well as pyrite and chalcopyrite, volcanic hot spring and associated native sulfur underground also provide water medium and sulfur during the formation process of sulfate. 8. According to the EPMA of sample chalcopyrite and pyrite in Hongshan Cu-Au, the value of Cu/Ni is 0.98-34.72, mostly close to the value of 5, which shows that Hongshan deposit is a typical volcanogenic magmaic hypothermal deposit. Au and Ag, Zn, Te and Bi are positive correlation, Cu and Hg, Se, Sb are positive correlation, indicates Au and Cu don’t locate in the factor of mineralization of same mineralization groups. The reasons of gold concentration in the oxidation zone are: 1). Change of redox potential (Eh) makes gold to deposit from the liquid of mineralization zone; 2). PH is one of the most factors of gold’s deposition; 3). Soluble complex and colloid of gold can be adsorbed easily. 9. The biotite and hornblende K-Ar isotopic ages from the wall rock-quartz diorite, biotite granite and monzonite granite are 231.99±3.45Ma, 237.97±2.36Ma and 296.53±6.69Ma respectively. The ore-bearing rhyolitic breccia lava contains breccia of the biotite granite which indicates the volcanism and related Cu-Au mineralization occurred later than the granite, possibly in Mesozoic. K-Ar ages of granitoids in Sanya, Baishiquan and Hongliugou area and Molybdenite Re-Os age of Baishan Mo deposit all are in Triassic. Besides late Paleozoic magmatism, igneous magmatic event of Mesozoic was widespread in eastern Tianshan. 10. The K-Ar age dating indicates that the K-Ar age of Voltaite occurred below surface 1m is 56.02±3.98Ma, K-Ar age of Ferricopiapite occurred below surface 1.5m is 8.62±1.12Ma, K-Ar age of Yavapaiite occurred below surface 14 m is 4.07±0.39Ma, and K-Ar age of Voltaite occurred below surface 10 m is 14.73±1.73Ma. So the age interval of oxidation zone of Hongshan copper-golden bed is between 60 -3.38Ma. Oxidization occurred at Caenozoic era (from 65Ma), which can be identified through comparing with different deposits oxidation zone in other countries. The coupling between global tectonic event and climatic change event which occur from Caenozoic era has some effect on epigeosphere system, which can act on the surface of bed oxidation zone similarly. It induces that the age mentioned above coincide with collision of India-Asia and multistage uplifting of Qinhai-Tibet Plateau happened subsequently. Bed oxidation zone is the effect and record of collision and uplifting of Tibet Plateau. The strong chemical weathering of surface accumulation to which was leaded by PETM event occurred Paleocene and Eocene is the reason of Voltaite sharply rises. On the contrary, Ferricopiapite formed due to the global cold weather. The predecessor did much research through biota, isotopes, susceptibility, but this paper try to use different sulfate mineral instead of climatic change. So the research of sulfate minerals not only indicates a great deal of oxidized zone feature, but also the intergrowth of sulfate minerals may be used to trace paleoenviroment and paleoclimate of oxidation zone. 11. Analysis of the information of alteration and mineralization features of four bore cores, induced activity polarization well logging and Eh-4 geophysical section, deep mineralization anomaly objects of Hongshan ore districts shows low resistance, middle and high polarization, measurements of Eh-4 consecutive conductance section show the existing of concealed porphyry ore body deeper than 450m, on the top of and around rock body there are low resistance body ranged from 100-300Ω•m, this area may be the ore-bearing part. In a word, Hongshan Cu-Au deposit deposit is a combine of upper HS-style epithermal Au deposit and deeper porphyry mineralization system. It has great potential to find large HS-style epithermal-porphyry Au-Cu deposits. This paper consists of seven chapters and twenty seven sections. The geological character of deposit is basic condition in this work. Constitute of oxidation zone, research of sulfate mineral, relation between oxidation and primary zone, K-Ar ages of potassic sulfate are key parts of thesis. Genesis of ore deposit is the further expansion of this research. Analysis of ore-controlling factors is the penetration above basic. Analysis of potential is application of exploration.

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对洱海沉积物间隙水中溶解有机质(DOM)含量、紫外一可见吸收、荧光以及分子量等的垂直分布特征进行了研究。结果表明,DOC含量在沉积物一水界面明显富集,随后急剧下降,6cm处达到最小值,随后呈上升趋势。DOC与吸光度值、荧光发射光谱强度之间具有一定的线性相关关系。DOM的E3/EAL值范围在1-6之间,绝大多数在1—3.5之间。表征DOM中腐殖质来源的指标荧光指数值处于1.48—1.59之间,说明DOM以陆源输入为主。此外,洱海沉积物间隙水DOM分子量分布呈多峰分布模式,重均分子量(Mw)值在1462—1953Da之间,数均分子量(Mn)值在547—900Da之间,多分散性系数ρ值在2.02—3.05之间。随着沉积深度增大,Mw和Mn有略微的增大趋势,但变化不大。沉积物的氧化还原条件、微生物活动以及铁、锰氧化物等在沉积剖面的差异是控制间隙水中DOM各种地球化学特性的主要因素。

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本论文的主要研究内容有以下三个方面:(1)蒸馏一乙基化GC-CVAFS法测定天然水体中甲基汞方法的建立及应用;(2)乌江表层河水不同形态汞分布特征的研究;(3)以乌江中上游干流不同年龄水库(乌江渡水库和东风水库)为例,探讨水库对乌江河流汞输送的影响及水库内汞的迁移转化。通过本论文的研究,取得以下成果:1.建立了一种基于蒸馏一乙基化结合气相色谱(GC)一冷原子荧光(CVAFS)测定天然水体中甲基汞的分析方法。水样中甲基汞经蒸馏后与四乙基硼化钠反应生成挥发性的甲基乙基汞,由氮气吹扫捕集于Tenax管,然后由GC-CVAFS测定。该方法的回收率为88.2%-108.4%,平均相对标准偏差为5.4%。取45mL水样测定,方法的最低检出限为0.009ng/L。该方法能准确测定天然水体中甲基汞的含量,步骤简洁、快速,明显优于国内目前使用的其余测定水体甲基汞的方法。2.乌江表层河水总汞的浓度分别为:丰水期659ng/L,枯水期16.9ng/L,明显高于北美和欧洲一些没受污染的河流,表明乌江流域已存在一定程度的污染。乌江河水汞的主要形态为颗粒态汞,其占总汞的比例为丰水期84%,枯水期占52%,乌江河流汞的分布、迁移行为主要受颗粒态物质控制。3.根据输入一输出通量模型,估算出东风水库总汞净通量为-57785.1g/yr,占总汞输入量的40.2%;乌江渡水库总汞净通量为-23273.7g/yr,占总汞输入量的14.0%,两个水库都表现为总汞的“汇”。与总汞相反,两个水库都表现为甲基汞的“源”,东风水库甲基汞净通量为+284.7g/yr,占甲基汞总输入量的4.4%;乌江渡水库甲基汞的净通量为+6622.0g/yr,占甲基汞总输入量的80.1%。乌江渡水库甲基汞的“源”作用显著大于东风水库。4.乌江渡水库和东风水库水体总汞和甲基汞都呈现明显的季节变化,表现为春季>冬季、夏季。乌江渡水库水体总汞平均为冬季9.0ng/L、春季16.0ng/L、夏季7.9ng/L;东风水库水体总汞平均为冬季8.2ng/L、春季12.5ng/L、夏季9.4ng/L。水体甲基汞的平均值分别为:乌江渡水库冬季0.74ng/L、春季0.97ng/L夏季0.89ng/L;东风水库冬季0.74ng/L、春季1.12ng/L、夏季0.38ng/L。水库水体甲基汞与总汞之间有相关关系,但未达极显著水平(乌江渡水库,r=0.451*,n=24;东风水库,r=0.471*,n=27)。水库内汞和甲基汞的形态、含量以及分布受外源性输入、降水稀释、水库初级生产力水平以及水库运行方式等因素控制。5.乌江渡水库和东风水库沉积物总汞明显高于其它未受污染地区水库沉积物总汞。乌江渡水库沉积物总汞含量为254.7±44.3ng/g,东风水库沉积物总汞为171.0±23.0ng/g。两个水库沉积物总汞没有季节变化,且在沉积物垂直剖面上也没有明显的浓度梯度变化。与总汞相反,两个水库沉积物甲基汞在垂直剖面上有明显的梯度变化和季节变化。无机汞的甲基化作用主要发生在沉积物表层5cm以内。沉积物中甲基汞含量受微生物活性影响显著,通常在水库生物生产量和营养物输入量较大时甲基汞浓度也较高。沉积物甲基汞含量在两个水库都表现为冬季<春季<夏季,甲基汞含量以及甲基汞占总汞的比例为东风水库<乌江渡水库。6.沉积物间隙水中无机汞的含量没有显著的季节变化;与此相反,沉积物间隙水中甲基汞浓度表现出明显的季节变化。沉积物间隙水中甲基汞在垂直剖面上的分布趋势与沉积物中甲基汞的分布趋势相一致,沉积物间隙水中甲基汞含量与沉积物中甲基汞含量呈显著性相关(乌江渡水库,r=0.770**,n=75;东风水库,r=0.675**,n=75)。7.沉积物间隙水中无机汞和甲基汞是水体中无机汞和甲基汞的“源,,i但对乌江渡水库和东风水库而言,由于水体深度较大,水力停留时间较短,间隙水中扩散出来的甲基汞和无机汞对水库内水体中相应形态汞含量的影响程度有限。但这种影响作用为甲基汞>无机汞,乌江渡水库>东风水库。8.因采集的鱼多为人工饲养鱼(生长速度快、食物链短),两个水库鱼体总汞和甲基汞含量均低于国家食用标准。但乌江渡水库鱼体甲基汞含量以及甲基汞占总汞的比例均高于东风水库。可见,乌江流域水库鱼体甲基汞含量不取决于水库年龄,而受水库内水生食物链底端食物中甲基汞的含量控制。9.通过本论文的研究,得出由于被淹没土壤有机质含量较低,乌江流域水库无机汞甲基化的驱动力为水库内源性输入有机质。在一定的时间范围内,随着水库的发育,水库初级生产力水平的提高,内源性有机质输入量增加,会显著促进沉积物中无机汞的甲基化进程。