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171.
四川盐源西范坪斑岩铜矿床中存在大量钾长环斑结构。研究表明这一结构是由正在冷凝的岩浆分泌出的成矿流体与刚结晶的斜长石相互作用形成的。在流体 -矿物相互作用过程中 ,流体从已经结晶的矿物尤其是黑云母中萃取出大量铜等成矿物质 ,从而进一步提高了体系的成矿能力。钾长环斑结构的出现不仅为矿床的岩浆热液成因提供了佐证 ,而且是一种良好的找矿标志。  相似文献   
172.
建立了用于新药阿斯匹林铜的高效液相色谱分析方法 .采用YWG C1 8柱 ,在室温下 ,n(乙腈 )∶n(水 )(内含 0 .2 %三乙胺 ,用H3 PO4调pH值至 2 ) =32∶68为流动相 ,药用标准品阿斯匹林和水杨酸为对照品 ,在紫外 2 30nm处检测阿斯匹林和水杨酸的含量 ;阿斯匹林铜和水杨酸铜的最小检测限为 0 .0 52mg·L-1 ,0 .0 4mg·L-1 ;阿斯匹林铜和水杨酸铜的平均回收率为 99.7% ,99.9% .  相似文献   
173.
CSP薄板表面裂纹的形成机理与预防措施   总被引:9,自引:1,他引:9  
对薄板坯连铸连轧生产线(CSP)生产的钢板出现表面裂纹及边裂进行了研究,并对CSP钢板表面裂纹的形成机理及其影响因素进行了分析,提出了防止裂纹的措施.X-射线能谱分析结果表明:在基体与氧化铁皮间的界面富集有铜等低熔点杂质元素,钢中残余元素含量偏高是产生表面裂纹的主要原因.  相似文献   
174.
合成出化学式为 { [Cu(tren) ]2 (μ2 -CO3) } (ClO4 ) 4·H2 O(tren为N_氨乙基_二乙烯三胺 )的配合物。该配合物经过元素分析、红外和紫外 -可见光谱等结构分析 ,研究结果表明Cu (Ⅱ )具有三角双锥的配位构型 ,并被碳酸根CO2 -3阴离子桥联形成三核Cu (Ⅱ )配合物。变温 (5~ 30 0K)磁化率被测定和拟合 ,计算结果表明标题配合物中Cu (Ⅱ )离子之间存在着弱的铁磁性相互作用。  相似文献   
175.
在含Cu^2 甲酸溶液的连续光催化氧化实验中,意外地观察到一个恒定的COD去除现象,归因于铜离子的光沉积和沉积铜的氧化溶解的循环过程,这一机理通过扫描电镜测试及pH值,铜离子浓度和光电流在反应过程中的涨落现象得到初步的证实。  相似文献   
176.
Carbon isotopic composition of pedogenic carbonate can be used to estimate the proportion of C4 and C3 plants. Here we present carbon isotopic data of carbonate in a red earth section at Xifeng, central Loess Plateau. Results show that C4 vegetation increased in ∼4.4 Ma B.P., stabilized between 4.0 and 3.0 Ma B.P. The character and timing of C4 expansion on the Loess Plateau are similar, but different with other localities, e.g. Pakistan and Africa, implying that regional climate changes were main factors driving the expansion of C4 plants. This event is comparable in timing with increased aridity evidenced by Xifeng grain size and North Pacific eolian dust records. Therefore we argue that the Pliocene expansion of C4 plants in northern China might have been caused by the increased aridity, which in turn might be related to rapid uplift of the Tibetan Plateau.  相似文献   
177.
The results of paleogeomagnetics and geochemistry of the coral reef in well Nanyong 2 of Nansha Islands showed that the bottom of the black sedimentary interlayer corresponds to the conversion boundary line between Brunhes Postive Polarity and Matuyama Reversed Polarity (B/M) and the cold/warm (19/20) climatic conversion bounds on δ18O curve, 0.78 Ma ago; and the red sedimentary interlayer corresponds to the ReunionⅠpolarity excursion (reversion) of the geomagnetic field, 2.01—2.04 Ma ago. Comparing with the normal light-coloured coral reef rock, the magnetic susceptibility (c), residual magnetization intensity (Mr) and the content of MnO and Fe2O3 of the black sedimentary layer appeared obviously positive abnormity. The magnetic susceptibility (c), residual magnetization intensity (Mr) and the content of Fe2O3 of the red sedimentary layer also appeared positive abnormity. Combining with the analyzing results of paleontology, we hold that this pair of special and typical sedimentary interlayers was relative to the sudden change of paleoclimate, i.e. the global climatic change and its incidental polarity reversal of the geomagnetic field directly affected the living environment of the paleontological species as well as the dispersion and enrichment of some chemical elements, especially the elements sensitive to redox such as Fe and Mn. For example, the elements Fe and Mn concentrated in the glacial period would be largely oxidized and diluted when the climate warmed up suddenly, and the originally oxidized high valence Fe would be condensed again when the climate cooled suddenly. This is possibly one of the important reasons of appearing and disappearing of the red and black sedimentary events of coral reef in well Nanyong 2.  相似文献   
178.
The faunal ecological type and sequence in the Tertiary red clay indicate that Hipparion fauna during the period 7.4-6.1 Ma in the middle reaches of the Yellow River is composed mainly of dorcadoides and mixed types. This represents semiarid veld environment with small fluctuation. The fossil assemblages characterized by the abundance of gaudryi types and even the occurrence of some Hominoid and Chalicotherium indicate an obviously warm and humid period since 5.3 Ma. The fossil assemblages during 3.4 Ma show the typical steppe fauna representing dry climate. It is indicated by the changes of ecological sequence that the climatic conditions in Pliocene are drier than that in late Miocene. The clay-skin content of red clay, which has a synchronous change with faunal features, is a rather good replacing palaeoclimatic index.  相似文献   
179.
The faunal ecological type and sequence in the Tertiary red clay indicate that Hipparion fauna during the period 7.4–6.1 Ma in the middle reaches of the Yellow River is composed mainly of dorcadoides and mixed types. This represents semiarid veld environment with small fluctuation. The fossil assemblages characterized by the abundance of gaudryi types and even the occurrence of some Hominoid and Chalicotherium indicate an obviously warm and humi period since 5.3 Ma. The fossil assemblages during 3.4 Ma show the typical steppe fauna representing dry climate. It is indicated by the changes of ecological sequence that the climatic conditions in Pliocene are drier than that in late Miocene. The clay-skin content of red clay, which has a synchronous change with faunal features, is a rather good replacing palaeoclimatic index.  相似文献   
180.
中国南方红土的研究进展   总被引:10,自引:0,他引:10  
中国南方的红土是晚新生代以来重要堆积物,为特定的气候环境下的产物,蕴藏着丰富的环境演化信息,为全球变化的 良好信息载体,作者对红土的成因、发育期次、年代学、古气候学、生物学、磁学性质等方面的不同观点作了较为详细的论述,从而提出了目前红土研究中存在的问题及解决的方法。  相似文献   
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