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921.
2-(2-苯并噻唑偶氮)-5-二羧甲氨基苯甲酸的合成及其应用——多元显色体系光度法测定金属材料中的镍 总被引:2,自引:0,他引:2
报道了新显色剂2-(2-苯并噻唑偶氮)-5-二羧甲氨基苯甲酸(BTACB)的合成,研究了在十二烷基硫酸钠(NaLS)存在下Ni~(2+)与BTACB形成蓝紫色配合物的条件,其λ_(max)~(MR)=600nm,ε=2.79×10~4L·mol~(-1)·cm~(-1),Ni在0~0.6μg/ml范围内服从比尔定律,反应具有一定的选择性。方法已用于直接测定铝合金、纯镁及含一定量Co的钢铁中痕量Ni和经萃取分离后测定纯钴中痕量Ni。 相似文献
922.
743离子交换快速分离—等离子体光谱法同时测定十五个稀土元素 总被引:1,自引:0,他引:1
本文研制了适用于地质样品中15个稀土元素分析的快速方法。样品经碱熔沉淀分离和743阳离子交换树脂分离富集将稀土元素制备成溶液用等离子体光谱法(ICP-AES)进行测量。方法检出限为0.002-0.3μg/g,当稀土元素含量为0.5-80,μg/g时,方法相对标准偏差为15%-2%。本方法经过多年的样品分析考验以及不断的改进和完善,证明方法简便快速,分析数据稳定可靠,能很好地满足地质样品中15个稀土分量测定的要求。 相似文献
923.
Tectonic Units and Their Fundamental Characteristics on the Northern Margin of the Alxa Block 总被引:6,自引:0,他引:6
Wu Tairan Geology Department China University of Geosciences Beijing He Guoqi Geology Department Peking University Jiang Minxi 《《地质学报》英文版》1993,67(4)
The northern margin of the Alxa block is the junction of a tectonic units. Four first-order tectonic units are distinguished: 1. the Yagan structural zone characteristic of an immature island arc; 2. the Zhusileng-Hangwula structural zone, which was a passive continental margin in the Early Palaeozoic and was transformed into an active continental margin in the Late Palaeozoic;3. the Shalazha structural zone characteristic of a mature island arc; 4. the Nuru-Langshan structural zone, which was a Proterozoic orogenic belt and later evolved into an extensional transtional crust in the Palaeozoic. The above-mentioned tectonic units differ remarkably in sedimentary formations, magmatic rock associations, metamorphism and geochemistry and are bounded by faults between one another. 相似文献
924.
925.
An experimental survey of the gold concentrated from well water by a hydroelectrical extraction (HEE) method has been carried out in the famous Au metallogenic province in the eastern part of Shandong Province in northeastern China. This method is based on the existence of ionic Au in groundwater around ore bodies. Under the action of an external electric field, ionic Au migrates toward the cathode where the metal is absorbed by a special absorbent attached to the cathode. Promising areas for further exploration can be evaluated from the amount of Au in the absorbent.Distinct Au anomalies were discovered by the experimental survey. The results from the follow-up study of some of these anomalies have shown that most of them are related to the known placer Au deposits and to the primary Au occurrences. However, two new Au prospects and several new Au sources have been found which offer new targets for Au hunting in the area.The hydroelectrical extraction method is an effective technique of looking for Au in areas covered with transported overburden. Since the Au in well water can be concentrated on the cathode with the absorbent, the sensitivity requirement for Au analysis could be reduced. The method also provides a useful tool for the exploration of blind placer Au. 相似文献
926.
Schuman Wu 《Tectonophysics》1989,170(3-4):171-182
In a low-temperature environment, the thin-section scale rock-deformation mode is primarily a function of confining pressure and total strain at geological strain rates. A deformation mode diagram is constructed from published experimental data by plotting the deformation mode on a graph of total strain versus the confining pressure. Four deformation modes are shown on the diagram: extensional fracturing, mesoscopic faulting, incipient faulting, and uniform flow. By determining the total strain and the deformation mode of a naturally deformed sample, the confining pressure and hence the depth at which the rock was deformed can be evaluated. The method is applied to normal faults exposed on the gently dipping southeast limb of the Birmingham anticlinorium in the Red Mountain expressway cut in Birmingham, Alabama. Samples of the Ordovician Chickamauga Limestone within and adjacent to the faults contain brittle structures, including mesoscopic faults and veins, and ductile deformation features including calcite twins, intergranular and transgranular pressure solution, and deformed burrows. During compaction, a vertical shortening of about 45 to 80% in shale is indicated by deformed burrows and relative compaction of shale to burrows, about 6% in limestone by stylolites. The normal faults formed after the Ordovician rocks were consolidated because the faults and associated veins truncate the deformed burrows and stylolites, which truncate the calcite cement. A total strain of 2.0% was caused by mesoscopic faults during normal faulting. A later homogenous deformation, indicated by the calcite twins in veins, cement and fossil fragments, has its major principal shortening strain in the dip direction at a low angle (about 22°) to bedding. The strain magnitude is about 2.6%. By locating the observed data on the deformation mode diagram, it is found that the normal faulting characterized by brittle deformation occurred under low confining pressure (< 18 MPa) at shallow depth (< 800 m), and the homogenous horizontal compression characterized by uniform flow occurred under higher confining pressure (at least 60 MPa) at greater depth (> 2.5 km). 相似文献
927.
新疆北天山巴音沟蛇绿岩的地质特征 总被引:3,自引:1,他引:3
巴音沟蛇绿岩虽受强热构造作用肢解,但仍保存有较完整的蛇纹石化超基性岩、状层辉长岩、基性熔岩(下部块状、上部枕状)和放射虫硅质岩的层序组合。岩石化学、地球化学、放射虫等古生物资料表明,它代表一个中石炭世陆缘海盆迅速扩张形成的洋壳和上地幔的残片。其侵位发生在中石炭世未海盆的封闭期间。 相似文献
928.
基于GIS的岩溶地区水土流失遥感定量监测研究——以贵州省(原)安顺市为例 总被引:1,自引:0,他引:1
本文主要介绍了基于GIS的水土流失定量评价模型的组成、各参数因子的算式算法 ,以及该模型在贵州省 (原 )安顺市的应用结果。模型是以修正的通用土壤流失方程 (RUSLE)为核心 ,在GIS中建立模型各因子空间数据 ,并通过PAMAP对它们进行综合分析。定量评价结果表明 ,(原 )安顺市年平均土壤流失总量为 86777吨 ,平均侵蚀模数为 4 0 9.4t/km2 ·a;轻度以上侵蚀面积 72 .7km2 ,强度以上侵蚀面积 53 .2km2 (含剧烈侵蚀面积 3 0 .9km2 )。其平均侵蚀模数与以往实测调查结果相比有 97.5%的一致性 ,表明该方法在贵州省岩溶地区的水土流失监测中具有较高的可靠性。 相似文献
929.
930.