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1.
《矿物岩石地球化学通报》2016,(1)
利用X射线粉末衍射仪、X射线荧光光谱仪、热分析仪、场发射扫描电镜表征手段研究了铜陵褐铁矿的矿物组成及其形貌形态特征,通过热处理方式获得褐铁矿纳米结构化相变零价铁作为动态柱填料并探究其除磷性能。结果表明,铜陵褐铁矿主要由针铁矿(90%)和石英组成,针铁矿晶体呈针状和片状,具纳米尺寸,集合体呈笋状和球状;热处理促使针铁矿进一步纳米结构化相变形成零价铁,具多孔结构、高比表面积特征;零价铁作为动态柱填料净化模拟含磷(5mg/L)废水可运行1年以上,磷去除效率超过99%,出水磷浓度达到城镇污水一级A排放标准(0.5mg/L)。研究结果可促进褐铁矿资源在保护环境中的应用,也为深度处理含磷废水提供一种新材料。 相似文献
2.
微量元素在铁、锰氧化物间的分配系数：古环境的新指标 总被引：1，自引：1，他引：0
借助顺序提取技术对西太平洋富钴结壳的铁、锰氧化物进行了分级提取,并利用电感耦合等离子体光谱仪测定了其微量元素的组成.结果表明:锰矿物相(δ-MnO2)主要富集Mn、Ba、Co、Ni、Sr;铁矿物相(FeOOH)富集Fe、As、Cu、Mo、P、Pb,V、Zn.计算了Co、Cu、Ni和Zn元素在铁、锰两相之间的分配系数D=(M/Fe)铁相/(M/Mn)锰相,探讨了其作为古环境替代指标的可行性.发现Co、Cu、Ni和Zn的分配系数与其在富钴结壳中的总质量分数无关,而与海洋生产力存在明显的正相关,其作用机理有待于进一步的研究. 相似文献
3.
为研究元素在基岩-土壤-作物系统的迁聚特征,选取湛江市徐闻县菠萝主产区为研究区,采集土壤和菠萝样品,结合元素迁移系数、生物富集系数评价了基岩-土壤-菠萝系统元素的分布和迁聚特征。结果表明: 研究区土壤含富磷(TP)、土壤全铁(TFe2O3)、Co、Ge、S、Se含量丰富,土壤全氮(TN)含量中等,有机质含量以中等—较丰富为主,土壤全钾(TK)含量缺乏。基岩风化成土过程中,土壤中Pb、Cr、TFe2O3、Ni相对基岩表现为富集,Al2O3、Cu、Zn、Co、Mn、TP、K2O相对基岩表现为流失; 土壤中Co、Cr、Cu、Ge、Mn、Ni、Zn主要来源于磁铁矿风化蚀变,Se主要来源于黄铁矿风化蚀变。菠萝果实对Cd、Hg为微弱吸收,Cd相对其他元素更容易在菠萝果实中富集。Ge、As、Cd、Se、Ni在菠萝根部最为富集,Pb、Hg、Cr、Cu、Zn在菠萝叶片最为富集,菠萝果实对Cu、Pb、Cr、Hg的吸收存在协同作用。研究成果可为当地菠萝产业发展提供依据。 相似文献
4.
新疆昆仑山布喀达坂峰-依吞布拉克一带岩石地球化学特征及元素分布规律 总被引：1，自引：1，他引：1
新疆昆仑山东段布喀达坂峰-依吞布拉克一带区域岩石地球化学特征表明：长城系富集W、Pb；奥陶系富集Au；二叠系富集Cu、Zn、Hg、Sb；三叠系富集Zn、Pb、Ag；三叠纪石英斑岩富集Cu、Zn、Hg、Sb．元素区域分布规律表明：与全国高寒山区平均水平相比，工作区相对富集Ba、Hg、Pb、Sn、Mo元素，贫化铁族元素；工作区可分为北、中、南3个地球化学带．北带形成了富集Au、Ag、Sb、Hg、Cu、Zn、Pb、Mo、Mg及铁族元素，贫化Cr、Co、Ni、Li、Be、Bi元素地球化学带；中带富集Cu、Pb、Zn、Ag、W、Sn、Mo、U、Th，贫化Hg、Li及铁族元素，形成了有色、稀有稀土、放射性元素地球化学带；南带富集Au、As、Sb、Hg、Cu、Zn，形成了贵重、有色元素地球化学带．石英斑岩富集Cu、Zn、Hg、Sb元素．祁漫塔格带元素组合与斑岩型铜钼矿、层控型Pb、Zn矿和夕卡岩型铁多金属矿床元素组合相似．第四系元素含量均一，不存在元素大面积区域性富集与贫化的物理化学条件． 相似文献
5.
基于福建省龙海市4类典型成土母质的垂向土壤剖面样品分析数据,研究了常量组分和微量元素含量及剖面分布特征。结果表明:研究区在温暖湿润气候条件下,化学风化作用强烈,Ca、Mg、Na、Si、K淋失贫化,含量明显低于全国均值,Al、Fe则相对富集,风化淋溶系数(ba)和硅铝铁率(Saf)值远低于全国土壤,土壤风化程度达到脱硅富铝铁阶段,花岗岩类成土母岩区风化作用尤为强烈;剖面土壤环境质量总体较好,微量元素含量与成土母质密切有关,九龙江口冲海积成因(剖面1)土壤重金属含量明显高于其他3个剖面;多数微量元素垂向分布受常量组分的控制,As、Cd、Cu、Hg、Pb、Zn与土壤中Fe等组分具有显著正相关性。因表层土壤中细粒黏质组分随地表径流淋失或下渗迁移,导致表层土壤低Fe、Al和重金属元素;在生物地球化学循环和人为污染的影响下,Hg、Cd、Pb、Zn等在表层土壤呈富集特征;多数重金属元素的相对富集系数小于1.0,且表层土壤无明显富集特征,认为除Hg、Pb等少数重金属元素外,其他元素受人为污染影响较小。 相似文献
6.
李广贺 《吉林大学学报(地球科学版)》1988,(1)
本文以野外土化学分析资料和室内原状土Ph(Ⅱ)、Cu(Ⅱ)和Hg(Ⅱ)的混合溶液淋滤实验资料为基础,以热力学基本原理为理论根据,建立Pb(Ⅱ)、Cu(Ⅱ)和Hg(Ⅱ)在土层系统中的迁移形式的数学模型。以此,评价Pb(Ⅱ)、Cu(Ⅱ)和Hg(Ⅱ)在包气带土层系统中的积累位置、积累方式及其迁移条件。确定配位体(∑HCO~-_3、∑Cl~-,∑SO~(2-)_4)浓度变化对于Pb(Ⅱ)、Cu(Ⅱ)和Hg(Ⅱ)稳定迁移形式和稳定迁移浓度大小的影响程度。 相似文献
7.
《矿物学报》2017,(6)
游离态Fe(Ⅱ)与磁铁矿的相互作用对环境污染物具有较强的还原活性。在自然界中,磁铁矿结构中的Fe2+和Fe3+常被过渡金属类质同像置换,显著改变磁铁矿的结构特征,物理化学性质和表面反应性。本研究考察了锌类质同像置换对磁铁矿与Fe(Ⅱ)共存体系去除Cr(Ⅵ)活性的制约及其机制。系列锌置换磁铁矿(Fe3-xZnxO4,x=0,0.25,0.49,0.74和0.99)用共沉淀法制备,并用XRD、TG、比表面积、酸碱滴定等方法进行系统的结构和物理化学性质表征。研究结果表明:系列锌置换磁铁矿样品具有尖晶石结构,Zn置换没有明显改变磁铁矿的晶体结构。比表面积和表面位密度随Zn置换量的提高而逐渐增大。在中性条件下,Cr(Ⅵ)快速吸附到磁铁矿表面,然后逐渐被磁铁矿及其表面吸附态Fe(Ⅱ)还原,最终固定在磁铁矿表面。随着Zn置换量的增加,磁铁矿与Fe(Ⅱ)共存体系对Cr(Ⅵ)的去除效率呈现先降低,后提高的变化趋势,这主要归因于共存体系对Cr(Ⅵ)还原能力的降低和吸附能力的提高。 相似文献
8.
土壤-农作物重金属富集规律是土壤和农作物重金属风险管控的关键问题。通过实地调查、现场采样、实验测试、综合分析等方法,重点研究了金矿活动影响区内的土壤Hg、Pb、Cr、As、Cu、Zn等重金属元素的全量、有效态含量特征,以及小麦不同部位与立地土壤中重金属含量之间的关系。结果表明:土壤Hg、Pb、Cu元素累积显著,Hg、Pb含量平均超标倍数为6.65、2.04倍;土壤中Hg(34.44%)、Pb(83.31%)、Cu(44.24%)、Zn(40.82%)的有效态含量占相应重金属全量的比例高,是危害农作物的主要元素;小麦籽中Hg、Pb、Zn元素平均超标率分别为26.33%、100%、26.32%;除Zn元素外,Hg、Pb、Cr、As、Cu含量全部符合籽粒茎杆根须土壤的规律;重金属含量的富集率平均值排序为Zn(30.54%)Cu(10.33%)Pb(0.45%)As(0.38%)Hg(0.14%)Cr(0.13%),Zn、Cu是小麦富集能力强的重金属元素。 相似文献
9.
对辽宁省鞍山一本溪地区经历了绿片岩一低角闪岩相变质的新太古代条带状铁建造中磁铁矿和黄铁矿矿物对的Fe同位素分析结果显示:相对于标准IRMM-014,所有样品的磁铁矿和黄铁矿均显示Fe的重同位素富集;且黄铁矿的Fe同位素比值均大于磁铁矿的Fe同位素比值(ε57Fe黄铁矿ε57Fe磁铁矿),两种矿物的Fe同位素比值之差为△57Fe黄铁矿-磁铁矿=2.23～5.13.黄铁矿富集铁的重同位素表明矿物的Fe同位素组成并不代表其原始沉积的特征,而是在区域变质作用过程中Fe同位素发生了交换的结果.由同位素平衡判别图解可知,在绿片岩一低角闪岩相变质作用中,磁铁矿-黄铁矿间的Fe同位素基本达到了平衡,且在平衡条件下黄铁矿比磁铁矿更富集Fe的重同位素,二者之间的Fe同位素平衡分馏系数α黄铁矿-磁铁矿≈1.000 4‰±0.06‰(2σ).这一研究成果是对变质作用过程中Fe同位素的地球化学行为认识的重要进展. 相似文献
10.
《地质科技情报》2017,(3)
运用纳米零价铁进行地下水污染原位处理是近年新发展的环境修复新技术,传统合成纳米零价铁一般多采用无氧条件(通氮气保护)液相法,操作繁琐,不适合批量生产。为了达到纳米零价铁液相法大规模制备和便于现场应用的目的,通过对比传统方法(通氮气除氧),提出在空气氛围中(有氧)制备纳米零价铁。透射电镜和X射线衍射分析表明,空气中直接制备的纳米零价铁Fe@Fe_2O_3有明显核壳结构,粒径40~100nm,内核零价铁,外壳氧化铁厚4~5nm。纳米铁降解水中甲基橙和去除六价铬的实验表明,空气氛围中制备的纳米铁反应活性最好,10min内0.4g/L(RO)Fe@Fe_2O_3能够把200mg/L甲基橙降解98.6%,30min内0.2g/L(RO)Fe@Fe_2O_3能够把20mg/L六价铬去除84.7%。因此,省略了氮气保护环节,成功合成核壳结构纳米零价铁,这有利于现场应用时现配现用,并降低运输保管纳米铁的成本和风险,对开展原位现场污染修复具有启示和应用价值。 相似文献
11.
A. Mesdaghinia M. T. Rafiee F. Vaezi A. Mahvi A. Torabian A. Ghasri 《International Journal of Environmental Science and Technology》2006,2(4):335-342
Jar-test experiments were conducted to study enhanced coagulation effectiveness in removal of disinfection by products (DBPs) from Zayandehrud River at Isfahan Province-the center part of Iran-in 2004. In this study, the removal of suspended and colloidal particles and natural organic matter (NOM) at various coagulant doses and coagulation pHs was assessed through raw and treated water measurements of turbidity, UV254 absorbance, TOC, and dissolved organic carbon (DOC). The trihalomethane formation potential (THMFP) was also determined by a mathematical relationship with TOC. Results indicated that NOM removal was a function of coagulant type, coagulant dose, and pH of coagulation. In general, TOC, DOC, and UV254 absorbance removal enhanced with increasing coagulant dose. However, further increases in coagulant dosage had little effect on disinfection by-products precursors removal. Ferric chloride was consistently more effective than alum in removing NOM. Coagulation pH was appeared to be a determining factor for maximum NOM removal and the removal of DBPs precursors by enhanced coagulation was significantly enhanced at pH 5.5 in comparison with initial pH of water. Furthermore, it is specified that preadjustment of pH with sulfuric acid reduced the coagulant dosage and thus, production of sludge. The reduction in THMFP was consistent with the trends observed for DBPs precursors removal data (i.e. UV254 and TOC data). 相似文献
12.
地层流体受两大流体系统的控制：压实流和重力流。利用流体势分析系统(简称FPAS)研究地下流体势及压力分布可克服井资料不系统的局限性，有效地进行油气资源的预测评价。由于琼东南盆地地质务件极其复杂，海洋油气勘探程度很低，勘探成本高，石油地质研究水平也比较低，分析认为区内有巨大的油气资源前景，但油气运移方向和路程均不清楚。用地下流体力场和势分析的方法可以统一处理和定量解释油气的运移和聚集规律，明确预测油气运移的主通道，确定有利的油气勘探靶区，显著提高钻探成功率。综合本区剖面、平面流体势及压力特征，结合其他有关地质资料，找出最有利的勘探目的层位。该方法在琼东南盆地松东地区的应用，取得了良好的效果。 相似文献
13.
M. Ichikuni 《Chemical Geology》1979,27(3):207-214
The uptake of F by aragonite is attributed to the ion-exchange process, in which one CO32? ion in the structure is replaced by two F? ions. Under the equilibrium condition at 15° C and 1 atm., the partition of F between aragonite and aqueous solution is described by: were [F] denotes the F content of aragonite in mol/g, and aF and aCa are the aqueous activities of F? and Ca2+, respectively. The equation was successfully applied to estimating the F content of marine aragonite. 相似文献
14.
ICP—AES法分析辉锑矿 总被引：1，自引：0，他引：1
本文针对辉锑矿成分复杂、主元素Sb易水解、部分元素易挥发,酸不溶元素的存在以及元素之间的干扰等问题,拟定了酸溶和碱熔分解试样的分析流程。在酸溶系统中结合TBP萃淋树脂和巯基棉分离富集分组,ICP-AES法测定Fe、Ca、Mg、Cu、Mn、Pb、Zn、Co、Ni、Au、Ag、In、Tl、Cd、Bi、Ga、Mo、Se、Te、As等20个元素。碱熔系统不分离主元素,用校正因素校正元素间光谱干扰并采用内标法ICP-AES测定Al、Ti、V、Ba、Sr、Sn、Sc、Cr、Be、Si和Sb等11个元素。试样验证表明,方法可行。 相似文献
15.
Fluoride uptake by serpentine depends on a number of parameters, viz. the chemical composition of serpentine, its particle size, pH of the medium, etc. Exchangeable (OH)? in serpentine minerals is essential for fluoride uptake. Data are also presented indicating the existence of an equilibrium between the fluoride concentrations in the solution and that taken up by serpentine over a wide range of experimental conditions. The available evidence strongly suggests the proxy of F? for (OH)? group as contributing to the principal mechanism of the process. 相似文献
16.
17.
L. M. Pavlova V. I. Radomskaya L. P. Shumilova A. M. Ionov P. Sorokin 《Doklady Earth Sciences》2017,473(2):457-460
The mechanism of platinum biomineralization by microscopic fungi is displayed based on data of electron microscopy, infrared and X-ray photoelectronic spectroscopy. It was suggested the platinum sorption process by microscopic fungi has some stages. The initial interaction is carried out by the mechanisms of physical and chemical sorption. Hereafter the reduction process of adsorbed platinum ions up to zero state is performed, probably, for account of organic compounds, which are produced by fungi biomass as metabolism result, and the process terminates by nulvalent particles aggregating up to nanosize forms. Obtained data on the platinum biomineralization extends the concept concerning the character of forming platinum nanoparticles in carbonous paleobasin. 相似文献
18.
《岩土力学》2017,(7):1869-1877
场地地震液化灾变(液化触发与震后变形)评价对基础设施抗震设计和安全服役有重要意义。为研究目前常用地震动强度指标IM的液化灾变评价能力,开展水平饱和砂土场地离心机振动台模型试验,对模型在50 g离心加速度下进行了20次不同幅值的振动,得到了液化与非液化响应数据。基于振动台台面输入建立峰值加速度a_(max)、地震剪应力比CSR、阿里亚斯强度I_a和累积绝对速度CAV_5的算法,并利用模型试验数据检验了这几种IM与液化触发和震后变形的相关性。分析表明,几类IM对液化触发的评价能力接近,且从超静孔压产生到初始液化触发都存在明显的IM阈值;几类IM对震后沉降评价能力有一定差异,其中I_a和CAV_5优于a_(max)和CSR,并对造成上述差异的原因做了初步分析。文中研究为选择合理的地震动强度指标评价场地液化灾变提供了科学依据。 相似文献
19.
H.-C. Kuo D.-F. Juang L. Yang W.-C. Kuo Y.-M. Wu 《International Journal of Environmental Science and Technology》2014,11(6):1661-1668
The purpose of this study was to investigate the effect of phytoremediation on soils contaminated with heavy crude oil using plants infected by mycorrhizal fungi. Five plant species, Vetiveria zizanioides, Bidens pilosa, Chloris barbata, Eleusine indica, and Imperata cylindrica, infected with the species of mycorrhizal fungi Glomus mosseae, were selected for this study. The degradation of total petroleum hydrocarbons in soils and several physiological parameters of plants such as shoot length and biomass were analyzed. Out of the 5 plant species tested, only V. zizanioides, B. pilosa, and E. indica could take up the G. mosseae. Out of these three, V. zizanioides showed the greatest growth (biomass) in soils with 100,000 mg kg?1 total petroleum hydrocarbons. In addition, B. pilosa infected with G. mosseae was found to be able to increase degradation by 9 % under an initial total petroleum hydrocarbons concentration of 30,000 mg kg?1 in soils after 64 days. We conclude that plants infected with mycorrhizal fungi can enhance the phytoremediation efficiency of soils contaminated with high concentrations of heavy oil. 相似文献
20.
A Practical Procedure for the Measurement of Fragmentation by Blasting by Image Analysis 总被引：1，自引：0，他引：1
Summary. The operation of a digital image analysis system in a limestone quarry is described. The calibration of the system, required
in order to obtain moderately reliable fragmentation values, is done from muckpile sieving data by tuning the image analysis
software settings so that the fragmentation curve obtained matches as close as possible the sieving. The sieving data have
also been used to extend the fragment size distribution curves measured to sizes below the system’s optical resolution and
to process the results in terms of fragmented rock, discounting the material coming from a loose overburden (natural fines)
that is cast together with the fragmented rock. Automatic and manual operation modes of the image analysis are compared. The
total fragmentation of a blast is obtained from the analysis of twenty photographs; a criterion for the elimination of outlier
photographs has been adopted using a robust statistic. The limitations of the measurement system due to sampling, image processing
and fines corrections are discussed and the errors estimated whenever possible. An analysis of consistency of the results
based on the known amount of natural fines is made. Blasts with large differences in the amount of fines require a differentiated
treatment, as the fine sizes tend to be the more underestimated in the image analysis as they become more abundant; this has
been accomplished by means of a variable fines adjustment factor. Despite of the unavoidable errors and the large dispersion
always associated with large-scale rock blasting data, the system is sensitive to relative changes in fragmentation. 相似文献