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111.
以浙江和新疆的膨润为原料合成了氧化铬-铝混杂柱支撑蒙脱石。分别用铝盐及铬盐溶液,经碱水解生成的聚羟基铬-铝混杂阳离子的成柱溶液,聚羟基铬-铝混杂阳离子通过阳离子交换引入蒙脱石,所得产物的性质用X射线衍射、热分析、红外光谱和BET比表面及孔径分布测量等方法研究并与氧化铬柱支撑脱石(简称铬蒙脱石)的性能进行比较,所得氧化铬-铝混杂柱支撑蒙脱石(简称铬-名蒙脱石),其基面间距较高(2.1nm^2/g,这  相似文献   
112.
根据赤峰沸石矿的XRD分析数据,经JCPDS卡片检索,定性分析出矿石中的各矿物相,然后结合其化学成分分析结果,利用化学成分满足法(MOSCC)算算出矿石中各矿物的含量(wt%).  相似文献   
113.
The interaction of γ-rays with smectite clays induces noticeable changes in the structure and physicochemical properties of the minerals. For sodium-montmorillonite, Mössbauer spectra show that γ-irradiation causes a partial reduction of trivalent iron to the divalent state due to hydrogen radicals production from the radiolysis of interlayer water. The XRD results show no change in the interlayer space upon irradiation and therefore the radiolysis of interlayer water causes no measurable changes in the architectural organization of the interlayer environment. Intercalation of simple organic molecules (ethylene glycol, tert-butanol and tetraalkylammonium salts) causes partial oxidation of structural divalent iron and affects the Mössbauer parameters of the M1 and M2 ferric components. Irradiation of ethylene glycol- or tert-butanol-clay composites indicates reduction of trivalent iron to the divalent state. XRD data show that the irradiation of clay-ethylene glycol complex causes collapse of the initial double layer of glycol molecules to a single layer complex. Finally, XRD results show that the effects of γ-irradiation on clay-tetraalkylammonium complexes depend upon the chain length of the organic cations.  相似文献   
114.
江苏镇江—扬州长江公路大桥桥基断裂断层泥定量研究   总被引:7,自引:1,他引:6  
汪明武  罗国煜 《地质论评》2000,46(4):437-442
本文通过断裂层泥的矿物组分特征、粒度成分结构和分形、成熟度和目前活动度、石英碎屑形貌SEM观测来分析与评价镇江至扬州长江公路大桥桥基断裂的抗震和抗断问题,得到主要影响桥基稳定性的NW-NNW向世业洲场区优势断裂,主要活动时间为Q3-Q2。该研究对断裂带上建设特大型桥梁工程的区域稳定性综合研究和论证,以及对大桥工程的合理选址、设计和确保安全具有重大实际意义。  相似文献   
115.
Marine clay deposits are encountered in the coastal regions of the world. They are soft in consistency with low shear strength and are highly compressible. The properties of these deposits are complex and diverse, and they mainly depend on the minerals present and microstructural arrangement of constituent particles. In the present investigation, the physico-chemical properties of the sediment samples obtained from marine deposits of east and west metropolitan coastal cities of India are discussed, and the test results obtained are compared with the synthetic samples such as bentonite and kaolinite. Mineralogical and fabric studies were carried out using scanning electron microscopy and x-ray diffraction techniques. Several consolidation and strength tests were carried out to study the engineering behaviour of these deposits. The strength and compressibility (Cc) values of these deposits varies from 27 to 45 kN/m2 and 0.37 to 0.81 respectively. XRD studies confirm the presence of highly compressible clay minerals such as smectite, vermiculite, chlorite and traces of the low swelling mineral, kaolinite. The fabric studies indicate that the constituent particles were arranged in an open network, or flocculated structure resulting in a high void ratio.  相似文献   
116.
湖泊沉积物碳酸盐含量的XRD半定量分析   总被引:1,自引:1,他引:0  
杨波  刘兴起  王永波 《湖泊科学》2014,26(4):637-640
湖泊沉积中的碳酸盐对于气候环境具有很好的指示意义.利用化学分析方法(气量法)和X衍射(XRD)方法,对青藏高原可可西里库赛湖KS-2006孔沉积物中的碳酸盐含量进行了半定量分析.结果表明:虽然KS-2006孔沉积物中的矿物种类达9种之多,且XRD的测量误差(±5%)高于气量法的测量误差(±0.8%);但XRD法获得的KS-2006孔沉积物碳酸盐总含量的平均值(18.9%)以及波动范围(7%~39%),同气量法所获得的碳酸盐含量的平均值(19.4%)和波动范围(5.0%~30.7%)基本一致,而且二者具有很好的正相关关系(相关系数R2为0.3940),随深度的波动趋势一致,说明XRD方法在半定量分析湖泊沉积物碳酸盐矿物种类及其含量方面,具有很高的可靠性.  相似文献   
117.
118.
采集了东南太平洋热液区DYl15-20V一$35一TVGl7站位的沉积物硫化物样品,其含有76.717%(m/m)强还原性的磁性良好的黄铁矿.以乳酸钠为电子供体,不溶性的氢氧化铁为电子受体,对该样品进行Fe¨还原细菌的定向富集培养.通过构建该茵群的16SrDNA基因文库,随机挑选82个阳性克隆子进行群落结构多样性分析.研究结果表明:82个克隆代表的6种基因型分别属于4个主要类群,其中ε一变形杆菌占有绝对优势,达到55.2%.此外其还包括厚壁菌门、β一变形杆菌和仅.变形杆菌,克隆子比例依次为27.6%、10.3%、6.9%.在富集产物中还原氢氧化铁的功能菌群主要是具有硫还原作用的ε一变形菌中的硫还原菌.  相似文献   
119.
Graphite from deposits occurring in the high-grade metamorphic rocks and their larteritized equivalents of the Thodupuzha-Kanjirappally Belt in Madurai Granulite Block, southern India is structurally fully ordered (crystallite size, Lc(002) ranging from 469 to 749 Å), possess high degree of graphitization (DG value ranging from 105 to 267 Å) and reflect crystallization at high temperature (700±100°C). Raman spectra of graphite display profiles corresponding to high crystallinity and high structural ordering. The high temperature crystallinity characteristics of graphite were not obliterated during retrogression of granulites to amphibolite facies gneisses. Preliminary carbon stable isotope results show a spread in isotope values from —11.8 to —26.8 %, which suggest more than one sources for carbon. The lighter carbon isotope values are suggestive of biogenic origin, whereas the heavier ones are probably fluid precipitated graphite.  相似文献   
120.
This study provides a measurement of success rate of Raman spectroscopy for mineral identification, and a direct comparison of powder X‐ray diffraction (PXRD) is provided by applying the same procedure for measuring its success rate against the identical set of samples. Consistent, standardised analytical procedures were applied to a set of fifty‐five minerals, and a success score was assigned to the results of each analytical method for each sample. For each analytical method, an average success rate (on a scale of 0–100) was calculated from these success scores. The success rate measured for powder XRD is 89, while the success rate for Raman spectroscopy came to 77. As the most common analytical challenge in Raman spectroscopy is specimen photoluminescence (PL), an estimate of the impact of technological advances that would eliminate this interference is provided by recalculating the success rate after removing the samples that produced PL interference from consideration. The resulting no‐PL success rate of 90 indicates that the success rate of Raman spectroscopy would be quite comparable to powder XRD if PL interference could be removed from Raman spectra.  相似文献   
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