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1.
本文根据从横径地区获得的温泉水、气体和同位素化学成分资料,系统地研究了该区地热水的成因。水、气体、同位素地球化学研究表明,横径地区热水的形成与岩浆和火山活动无关;地热水主要起源于大气降水,其中气体组分起源于大气、地壳和地幔的混合;地热水处在中低温的地热储中;地热水的补给区位于乌泥障地区,其补给区可能的高程为337.5-743.6m。  相似文献   

2.
一个新的交叉学科——绿色化学   总被引:1,自引:0,他引:1  
绿色化学致力于节约资源,从源头上防止污染物的生成,它是涉及整个化学领域的一个交叉学科。本文介绍绿色化学的提出、发展和研究内容,作者认为高校是绿色化学发展的重要力量。  相似文献   

3.
矿物热膨胀的晶体化学研究综述   总被引:2,自引:0,他引:2  
热膨胀是矿物材料的重要属性之一,对它的研究在矿物学及材料科学中具有重要意义。前人关于矿物的热膨胀系数和晶体化学参数之间关系的研究表明,矿物的 结构、成分、化学键及原子价态、配位数、外层电子结构等对热膨胀系数都有不同程度的影响。晶体化学方法是研究矿物热膨胀系数的有效方法,但由 于矿物的热膨胀系数和晶体化学参数之间的定量关系尚未完全弄清,目前仅仅能对简单结构矿物的热膨胀系数进行计算,结构、成分较复杂的矿物的热膨胀系数计算尚缺乏好的晶体化学模型。为达到精确计算矿物热膨胀系数的目的,必须对矿物按照晶体化学特性进行分类。 在分类的基础上,把晶体化学方法和理论计算方法有效地结合起来。矿物的热膨胀性可按照 受热时结构有无旋转划分为键膨胀型和结构旋转型,过渡金属阳离子所形成的化合物根据d电子层电子云的分布进行分类。通过以上的分类,在计算不同类型矿物热膨胀系数时 ,可按矿物类型处理。对键膨胀型的矿物只需估计键的膨胀情况,而对于结构旋转型除考虑 键的膨胀性以外还要考虑配位多面体旋转的情况。  相似文献   

4.
岩石化学研究表明,洋后变质超镁铁岩是由变质方辉橄榄岩和变质超镁铁堆积岩组成。变质方辉橄榄岩的微量元素地球化学及矿物化学特征表明,应为亏损的残余地幔产物。通过系统的岩石地球化学、矿物化学及年代学研究,认为洋后变质超镁铁岩可能为华南晚震旦-早古生代的蛇绿岩组成部分。  相似文献   

5.
关于土壤中“化学定时炸弹”及其触爆因素的探讨   总被引:36,自引:1,他引:35  
运用目前环境科学研究中较为流行的“化学定时炸弹”的概念,详细分析了我国土壤中可能的“化学定时炸弹”。认为土壤中存在着地带性和泛地带性的“化学定时炸弹”,地带性的包括土壤盐渍化、土壤酸化等;泛地带性的包括施肥造成的、工业污染造成的及特殊成土作用形成的“化学定时炸弹”。同时,探讨了导致土壤中这些“化学定时炸弹”内在和外在的可能触爆因素。提出了今后开展该领域宏观和微观研究的方向和建议。  相似文献   

6.
应汉龙 《地质与资源》1995,4(4):247-254
本文研究了胶东邓格庄金矿床金银系列矿物、黄铁矿、石英和方解石的化学成分,金银系列矿物主要为银金矿和金银矿,含Pt等微量元素,与金矿化关系密切的黄铁矿以Fe亏损占优势,富Au、Te、As和Ag为特点;石英具高的Al、K、Cu、Pb和Zn,低的Li含量;黄铁矿、石英和方解石的稀土元素组成指示成矿热液可能有二种来源,方解石的稀土元素组成指示成矿热液为岩浆或深部来源。  相似文献   

7.
对流层活性卤素化学:充满机遇和挑战的研究领域   总被引:2,自引:0,他引:2  
活性卤素物种(RHS)参与大气对流层中许多化学过程,影响许多重要物种的源和汇,在大气对流层化学中起着十分重要的作用,因此对流层活性卤素化学成为近年来国际大气化学研究的重要前沿研究领域。RHS在对流层的外场观测方法主要包括化学放大、大气压化学电离质谱(APCIMS)、长程差分吸收光谱(DOAS)、雾室和湿法化学分析法、光解法、碳同位素的比率法等。各种观测方法表明大气边界层中存在着不同种类的RHS,特别在海洋边界层、极地边界层和盐湖地区。RHS的浓度有较大的变化范围(10-12~10-10)。RHS可引起一些VOCs的氧化,影响HOx和NOx的反应,减少对流层O3,并对硫的氧化和汞化学有较大的影响。对流层RHS的源主要为有机卤素化合物的排放和海盐气溶胶的释放。在讨论RHS在对流层的循环转化的基础上,归纳总结出一个示意图;提出了现有的主要科学问题,进而展望了今后的研究前景。  相似文献   

8.
 R-mode factor analysis of the recently acquired data on water and sediment chemistry has been performed. Basic chemical parameters have been merged together which aid in interpreting a few empirical geochemical factors controlling the chemical nature of water and sediments of the Gomti River, a major Himalayan tributary of the Ganges drainage basin. Water chemistry seems to be controlled by three factors: bicarbonate, rainfall and silicate and phosphate factors. Sediment chemistry is largely controlled by the following four factors: clay, adsorption/desorption, Fe-Mn hydroxide and mercury factors. These factors show spatial and temporal variability in terms of their R-scores. Received: 8 September 1997 · Accepted: 15 December 1997  相似文献   

9.
刘羽  贺英侠 《矿物学报》1992,12(4):359-366
本文通过对某些磷灰石的电子探针成分分析,X射线粉晶衍射及红外光谱特征的综合测试,发现这些磷灰石的晶体化学特征具有一定差异,因而有可能作为标型特征。其中与基性岩浆有关的磷灰石含OH~-较高,而CO_2较少;热液型的含氯较高,这可能是其α、c值较大的原因;沉积型的则以含明显的结构CO_2和高c/α值为特征。在各种地质作用中,CO_2均有可能进入磷灰石结构。根据红外光谱对比,推测2000cm~(-1)附近的吸收是磷灰石的固有吸收,它可能为PO_4的v_2吸收的倍频,也可能由与F、OH~-离子有关的振动引起。  相似文献   

10.
但德忠 《矿物岩石》1992,12(4):111-116
本文拟就流动注射分析在电分析化学中的应用和进展作一概略的回顾和讨论  相似文献   

11.
中国坡缕石晶体化学研究   总被引:13,自引:2,他引:13  
郑自立  田煦 《矿物学报》1997,17(2):107-114
本研究通过对坡缕石化学成分分析数据的系统数理统计分析及结合透射电镜研究提出了Al2O3、Fe2O3、Mgo同SiO2一样为坡缕石的自身氧化物组分,而CaO、K2O、Na2O、TiO2等为主要以吸附态存在的非自身氧化物成分。相应的坡缕石晶体化学式为(Mg、Al、Fe、)5SiO20。(OH)2:·4(H2O)·nH2O(□—空位)。Ala3 、Fe3 、Mg2 异价类质同象置换的线性方程为Mg2 =4.978-1.519(Al3 +Fe3 )。穆斯堡尔谱、红外光谱及(020)面网晶格条纹象的分裂研究表明了阳离子占位形式:MIM2M3M3M1,其中边缘M1=(Fex3+)(Mg),中间M3=(A13 +Fe3+),M2=Al3 (缺Fe3 )或M2=(Fe3 +Al3 )或等于(Fe3 )和(□)。坡缕石的Mg2 -Al3 -Fe3 组分三角形图解揭示了:富Fe外生沉积成因为主的土状坡缕石和贫Fe富Al的热液交代蚀变充填作用为主的纤维状坡缕石的成分成因分类。  相似文献   

12.
卞学洛 《地下水》2008,30(1):15-20
第四系第Ⅱ含水组地下水经长期开采,早已完成主固结过程;开采Ⅱ组地下水可使上覆咸水淡化越流,最终加快各类地表水的入渗,多年来在适宜地段大幅恢复Ⅱ组地下水的开采。经调查大部分水井水质恶化非含水层水质变化,绝大多数地区咸水底界没有下移趋势。笔者认为在滨海平原区能使咸、淡水保持数10万年高浓度差的粘土层,具有半透膜特性。由于部分观点与前人研究结果相左,澄清"井水咸化"与地下水咸化污染的区分就显得尤为重要。为此,将多年地下水水质调查资料进行分类,推进咸化污染机理研究推进。  相似文献   

13.
Water and sediment samples collected from the Gomti River, a tributary of the Ganges River system, during the postmonsoon season have been analyzed to estimate major elemental chemistry. Water chemistry of the River Gomti shows almost monotonous spatial distribution of various chemical species, especially because of uniform presence of alluvium Dun gravels throughout the basin. The river annually transports 0.34×106 tonnes of total suspended material (TSM) and 3.0×106 tonnes of total dissolved solids (TDS), 69 percent of which is accounted for by bicarbonate ions only. Samples collected downstream of the city of Lucknow show the influence of anthropogenic loadings for a considerable distance in the river water. Na+, Cl, and SO4 2– concentrations build up downstream. The bed sediment chemistry is dominated by Si (36 percent), reflecting a high percentage of detrital quartz, which makes up about 74 percent of the mineralogy of the bed sediments in the River Gomti. The average Kjeldahl nitrogen concentration (234 g/g) indicates indirectly the amount of organic matter in the sediments. The Hg concentration in sediments has been found to be higher (average 904 ppb) than the background value. The suspended sediments are well sorted, very finely skewed, and extremely leptokurtic, indicating a low energy condition of flow in the Gomti River. The influence of chemical loads in the Gomti has been found to be small or nonexistent on the Ganges River, perhaps because the water discharge of the Gomti (1.57 percent) to the Ganges is quite low.  相似文献   

14.
Column leaching tests on black coal mine washery wastes were performed, to determine the chemistry of acid generation. Coal mine coarse rejects and tailings were subjected to wet and dry cycle dissolution and subsequently column leached. The rates of iron sulphide oxidation and carbonate mineral dissolution were determined based on the drainage chemistry. The kinetic data from column leach experiments are used to predict the time required to deplete the acid producing and acid consuming minerals in the mine wastes. The acid production in the mine rejects was found to depend upon iron chemistry, carbonate chemistry, diffusion of oxygen, and permeability. The chemistry of the drainage from two different coal mines is compared.  相似文献   

15.
改性铝土矿做净水剂,与市售其它混凝剂比较,具有PH值适用范围宽,对水中阴阳离子,尤其是对SO^2-4的吸附能力强等优点。去除水中的浊度,颜色,COD等同于市售其它混凝剂。  相似文献   

16.
青藏高原北缘火山岩中辉石岩包体研究   总被引:7,自引:2,他引:7       下载免费PDF全文
青藏高原北缘可可西里鲸鱼湖、雄鹰台、双泉子火山岩中含有辉石岩包体 ,其主要矿物组成为单斜辉石和斜方辉石。辉石的化学成分与国内外幔源包体 -橄榄岩和辉石岩中的类似 ,与麻粒岩中的明显不同 ;辉石温压计计算结果表明 ,辉石形成的温度为 110 1~ 140 0℃ ,压力为 30× 10 8~ 6 0× 10 8Pa,结合岩浆动力学计算结果 ,推测岩浆的来源深度大于 15 0km ,这与地球物理研究得出本区地下深处存在低速层的结果相吻合。  相似文献   

17.
Mississippian shoal carbonates of Western CanadaSedimentary Basin are important hydrocarbon hosts.Dolomitization plays a major role in the evolution ofreservoir porosity in these carbonates. This processvaries across the basin and reflects, in part, divergentsources and chemistry of pore fluids. Dolomites fromseveral petroleum reservoirs were analyzed formineralogical, geochemical and isotopic variation. Thedata clearly demonstrate the progressive and complexrecrystallization of dolomite during shallow and deepburial in modified marine, meteoric and burial fluids.These data include: change in crystal size,stoichiometry, cathodoluminscence characteristics,stable oxygen and carbon isotopic shifts and changesin radiogenic Sr isotopic composition. However,regional geology, tectonic history and fluid flowevolution play important roles in the diageneticimprints and the degree of recrystallization.Early microcrystalline dolomite formed in normalmarine and evaporative conditions in Mississippiancarbonates from Western Canada Sedimentary Basinhave undergone variable degrees of recrystallization, frompristine dolomite akin to Holocene sabkha dolomitewith preserved mineralogical and chemical attributesto highly recrystallized mesodolomite, however stillnonstoichiometric, but with highly altered chemicalsignatures. Careful attention should be made to localgeology, hydrodynamics and fluid flow when investigatingdolomite recrystallization in sedimentary basins.  相似文献   

18.
What controls partial melting in migmatites?   总被引:4,自引:0,他引:4  
Abstract The layers of six stromatic migmatites from Northern, Western, and Central Europe display small but systematic chemical and mineralogical differences. At least five of these migmatites do not show any signs of largescale metamorphic differentiation, metasomatism, or segregation of melts. It is concluded, therefore, that the compositional layering observed in most of the investigated migmatites is due to compositional differences inherited from the parent rocks. Almost isochemical partial melting seems to be the most probable process transforming layered paragneisses, metavolcanics, or schists into migmatites.
The formation of neosomes is believed to be caused by higher amounts of partial melts formed due to higher amounts of water moving into these layers. The neosomes have less biotite and more K-feldspar, if K-feldspar is present at all, than the adjacent mesosomes. These differences are small but systematic and seem to control the access of different amounts of water to the various rock portions. Petrographical observations, chemical data, and theoretical considerations indicate a close relationship between rock composition, rock deformation, transport of water, partial melting, and formation of layered migmatites.  相似文献   

19.
一种新的隐伏矿勘查技术——地电化学法的现状和展望   总被引:2,自引:0,他引:2  
本文论述了国内外地电化学研究总体情况,着重介绍了各分支方法的基本原理和功能;国内外在机理研究方面所获进展、列举了几个成功的找矿实例;分析了我国当前存在的差距及必需采取的措施。  相似文献   

20.
用离散变分Xα 量子化学计算方法 ,研究了络合离子 [Au(Sb2 S4) ]-吸附在粘土矿物高岭石晶体边缘时 ,它们之间的化学键性质。根据所选用的络合离子 [Au(Sb2 S4) ]-处于基面及侧面不同位置的 10个模型的计算结果 ,表明当络合离子 [Au(Sb2 S4) ]-位于高岭石晶片的侧面时 ,比其位于基面时更为稳定 ,而且与高岭石晶片侧面中的O形成共价键。  相似文献   

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