A world model of soil carbon dioxide: A reply     

George A. Brook  Elgene O. Box 《地球表面变化过程与地形》1984,9(1):85-87

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陕西略阳煎茶岭镍矿床成矿及矿石变质过程的地球化学研究     

Zhang Benren Chen Dexing Hu Yikeng 《地球科学》1986,(4)

矿床中存在着岩浆离熔成因的磁黄铁矿-镍黄铁矿矿石和热液改造成因的黄铁矿-针镍矿-辉镍矿矿石。研究证明现在矿石中存在的硫化物均为较低温度条件下的变质产物,并且矿物组合的更替不仅同温度变化有关,同时还受体系中氧逸度和硫离子活度的控制。矿物组合的地球化学分析表明,现有Fe-Ni-S体系低温（<300℃）相平衡图解之间存在着矛盾的原因可能是忽略了氧化-还原条件的影响。  相似文献   

金矿床石英中负价氮的发现及赋存状态探讨     

许虹  田丽华 《吉林大学学报(地球科学版)》1995,(1)

利用ｘ光电子能谱测试，发现金矿床石英中有负价氮的存在。这种氮的结合能为３９８ｅＶ士，该结合能氮的化合物有多种，氦均为负价态，其中有Ｓｉ＿３Ｎ＿４Ｓｉ的ｘ光电子能谱有二个谱峰值：１０３．４ｅＶ和１０１．９ｅＶ，前者为ｓｉＯ＿２的结合能，后者为Ｓｉ＿３Ｎ＿４的结合能。Ｎ和Ｓｉ的结合能均表明石英中有Ｓｉ＿３Ｎ＿４为负三价态。石英中负价Ｎ可能为替代氧的类质同象成分。  相似文献   

Emission of aliphatic amines from animal husbandry and their reactions: Potential source of N2O and HCN     

Gunnar W. Schade  Paul J. Crutzen 《Journal of Atmospheric Chemistry》1995,22(3):319-346

We measured the emissions of volatile aliphatic amines and ammonia produced by the manure of beef cattle, dairy cows, swine, laying hens and horses in livestock buildings. The amine emissions consisted almost exclusively of the three methylamines and correlated with those of ammonia. The molar emission ratios of the methylamines to ammonia, and data on NH₃ emissions from animal husbandry in Europe, together with global statistics on domestic animals, were used to estimate the global emissions of amines. Annual global methylamine-N input to the atmosphere from animal husbandry in 1988 was 0.15±0.06 TgN (Tg=10¹² g). Almost 3/4 of these emissions consisted of trimethylamine-N. This represents about half of all methylamine emissions to the atmosphere. Other sources are marine coastal waters and biomass burning.Possible reaction pathways for atmospheric methylamines are shown. Among various speculative but possible products N₂O and HCN are of interest because the emission of methylamines could contribute to the global budgets of these compounds. Maximum atmospheric N₂O production from methylamines are below 0.4 Tg N/year, which is less than 10% of the annual N₂O growth rate. Although we do not expect the methylamine emissions to contribute in a major way to the atmospheric N₂O budget, more studies are needed to establish this conclusion beyond doubt. Similar conclusions hold for HCN.  相似文献   

Comparison between Pollutant Concentration in the Samples of Fog and Rime Water Collected at Mt. Milešovka     

Fišák  Jaroslav  Řezáčová  Daniela 《Studia Geophysica et Geodaetica》2001,45(3):319-324

The article aims at showing the differences in concentration of pollutants that are contained in the samples of fog and/or low cloud water in comparison with the water from rime. The results follow from the fog and rime measurements made at Mt. Mileovka (eské Stedohoí Mountains). They are compared with the results of other studies that also report the differences in fog and rime chemistry.  相似文献   

天然气中甲烷和CO2的二元同位素特征     

唐茂  赵辉  刘耘 《矿物学报》2007,27(3):396-399

不同成因的天然气由于形成温度不同，往往会有不同的稳定同位素特征。但是，由于经常不能同时获得天然气以及它的生成母体的同位素成分，很难用单独的C或H同位素成分来确定它的形成温度。在形成天然气时，不同的温度会形成不同的二元同位素的浓度，温度越低，二元同位素的比例越大，因此只需要知道天然气本身的二元同位素的浓度，就可以确定形成温度，从而避免了需要知道天然气生成母体的同位素成分这一难题。本文利用高级量子化学计算，预测了不同温度下天然气中甲烷和CO2气体的二元同位索（Clumped isotope）的特征，提供用于天然气成因分析的新方法。  相似文献   

新疆东准噶尔北部扎河坝富碱花岗质岩石矿物学特征及物理化学条件     

张东阳  高阳  苏慧敏  王鹏 《矿物岩石》2007,27(4):30-38

新疆东准噶尔北部扎河坝富碱花岗质岩石分布于乌伦古大断裂与额尔齐斯-玛因鄂博大断裂之间。富碱花岗岩类有石英碱性正长岩、碱性长石花岗岩、石英二长斑岩及碱性长石正长岩等岩石类型。在详细的显微镜观察基础上,全岩分析和电子探针分析结果表明,富碱花岗质岩中的矿物组合是碱性长石 石英 钠铁闪石 霓辉石,以出现高硅、富碱、贫铝、低钙、低镁、高铁、高锰、贫水为特征。铁钛氧化物温度计估算出的富碱花岗岩体结晶温度在650℃~755℃之间,氧逸度为10-17.17Pa~10-14.39Pa,结合钠铁闪石的特征,碱性岩浆演化后期存在着明显的水-岩作用,扎河坝富碱花岗质岩石形成于低压、高氧逸度、中高温环境,反映了相对开放、浅成的形成环境。  相似文献   

江西安远路迳金伯利质煌斑岩筒研究——一种新型的幔源碱性超基性岩   总被引：1，自引：0，他引：1  

叶松  杨眉  叶德隆  邰道乾  任迎新 《矿产与地质》2007,21(4):383-394

路迳岩筒属火山通道相,由金伯利质煌斑岩、角砾岩、角砾凝灰岩组成,富含幔源橄榄岩包体、普通辉石巨晶和岩球。造岩矿物是橄榄石、斜方辉石、单斜辉石、角闪石和金云母,深源特征指示矿物有镁铝榴石、铬透辉石、铬尖晶石和镁钛铁矿。岩石化学组成超低SiO2,低MgO,高Al2O3,富碱,富挥发组分。轻稀土元素富集,相容元素贫化,不相容元素明显富集。岩浆起源深度约85km。其中：岩体产状,富含包体、巨晶和岩球,岩石结构和构造,矿物组成,岩石化学组成超低SiO2、富碱、富挥发组分等特征与金伯利岩相似;但岩石化学组成高Al2O3,低MgO,K2O低于Na2O,REE和LREE/HREE偏低,部分微量元素的亏损或富集,金云母成分富TiO2,富TFeO,贫MgO,镁铝榴石、铬透辉石、铬尖晶石和镁钛铁矿的Cr2O3含量偏低,岩浆起源深度较浅,均与金伯利岩有重大差异,而更接近煌斑岩类。研究认为,是幔源岩浆岩的一种新类型,岩石名称界定为金伯利质煌斑岩。  相似文献   

Evaluation of ostracod-based palaeoenvironmental reconstruction with instrumental data from the arid Faiyum Depression,Egypt     

K. W. Keatings  I. Hawkes  J. A. Holmes  R. J. Flower  M. J. Leng  R. H. Abu-Zied  A. R. Lord 《Journal of Paleolimnology》2007,38(2):261-283

The utility of ostracod-based palaeoenvironmental reconstruction was evaluated using instrumental data for Lake Qarun, Egypt. The euryhaline ostracod Cyprideis torosa was the only species found in the lake’s recent sediment record. This species is known to tolerate salinity levels and water solute compositions that may prevent colonisation by other species. Oxygen and carbon isotope ratios of ostracod carbonate from lake sediments covary with changes in instrumental values for lake level and salinity for the period 1890–1974. δ¹³C-values correlate negatively with lake water salinity (r ² = 0.87) and δ¹⁸O-values correlate negatively with measured lake level changes (r ² = 0.41). Other ostracod proxy data provide qualitative information on lake level trends. Fossil assemblage data (juvenile/adult and valve/carapace ratios and valve preservation) provide information on wave energy. Ecophenotypic variation of C. torosa valves provided some useful palaeolimnological information. Sr/Ca and Mg/Ca ratios in ostracods were not found to reflect water composition, due to the uncoupling of these ratios with salinity in Lake Qarun. Overall, our results highlight the need to calibrate ostracod proxy data in modern systems prior to their use for palaeoenvironmental reconstruction.  相似文献   

用离子色谱法测定金矿区水样中常规无机离子   总被引：6，自引：1，他引：6  

黄园英  刘芬  罗锡明  贾刚军 《黄金地质》2002,8(2):69-73

利用DX－120离子色谱仪进行阴阳离子的精密度和准确度测定，100mg/L时相对标准偏差范围为1．00％－3．80％，回收经95．83％－105．00％；5mg／L时相对标准偏差范围为1．18％－4．57％，回收率92．40％－103．20％，完全达到实际要求。用该离子色谱仪测定甘肃阳山金矿山水样中常规无机离子，数据表明该区域水质较好，所测离子浓度都未超过饮用水标准。  相似文献