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91.
The Ombilin Basin is filled by late Eocene to early Oligocene marginal fan deposits (Brani Formation) and lacustrine shales (Sangkarewang Formation), unconformably overlain by a late Oligocene to early Miocene fluvial sequence (Sawahlunto and Sawahtambang Formations) and capped by an early to mid-Miocene marine sequence (Ombilin Formation). Significant oil shale deposits occur in the Sangkarewang Formation, intercalated with thin laminated greenish-grey calcareous sandstones. X-ray diffraction shows that the sediments consist mainly of quartz, feldspar, carbonates and a range of clay minerals, together in some cases with minor proportions of sulphides, evaporites and zeolites. Feldspar and non-kaolinite clay minerals decrease up the sequence, relative to kaolinite, suggesting a changing sediment source as the basin was filled. Calcite, thought to be mainly of authigenic origin, is also more abundant in the middle and upper parts of the sequence.The organic matter in the oil shales of the sequence is dominated by liptinite macerals, particularly alginite (mainly lamalginite) and sporinite. Cutinite also occurs in some samples, along with resinite and traces of bituminite. The dominance of lamalginite in the liptinite components suggests that the material can be described as a lamosite. Samples from the Sangkarewang Formation have vitrinite reflectance values ranging between 0.37% and 0.55%. These are markedly lower than the vitrinite reflectance for coal from the overlying Sawahlunto Formation (0.68%), possibly due to suppression associated with the abundant liptinite in the oil shales.Fischer assay data on outcrop samples indicate that the oil yield is related to the organic carbon content. Correlations with XRD data show that, with one exception, the oil yield and organic carbon can also be correlated directly to the abundance of carbonate (calcite) and inversely to the abundance of quartz plus feldspar. This suggests that the abundance of algal material in the lake sediments was preferentially associated with carbonate deposition. High yields of oil are noted in some samples, as a percentage of the organic carbon content. This may indicate that partial generation of hydrocarbons from the material has already taken place, in association with thermal maturation of the Sangkarewang succession.  相似文献   
92.
火法试金控制铅扣的氧化还原平衡方程探讨   总被引:1,自引:0,他引:1  
袁功启 《岩矿测试》2005,24(4):287-290
根据分析物料的性质及在高温熔融过程中的主要反应,运用数学方法确立控制铅扣的氧化还原平衡方程式,并以此推导出几种矿物的应用公式。对影响铅扣大小的其他因素进行了探讨。  相似文献   
93.
以纤蛇纹石石棉、陶瓷纤维、玻璃纤维、岩棉、硅灰石为受试物,采用噻唑蓝(MTT)比色法检测染毒72h后V79细胞的存活率,并通过吉姆萨染色观察细胞形态学上的变化。不同浓度ρ/(μg.ml-1)的矿物粉尘(100,200,400,600,800,1000)作用72h后,V79存活率下降,细胞增殖明显受到抑制并出现大量细胞衰亡,呈现出剂量效应关系,且细胞毒性大小为玻璃纤维>纤蛇纹石石棉>陶瓷纤维>硅灰石>岩棉;形态学观察发现染毒细胞出现空泡、肿胀、裸核、黑褐色颗粒以及胞浆胞核模糊、形态变化等现象,且不同的粉尘对V79细胞的影响不同。总体而言,岩棉是五种粉尘中毒性最低的石棉代用纤维。  相似文献   
94.
The mussel Perna perna was used to monitor and assess areas suspected of oil contamination by transplanting animals from unimpacted to impacted sites and vice versa. The deployment lasted for three months during which total PAH were measured in seawater samples collected every 15 days. PAH concentrations were determined in mussel tissue monthly. The lysosomal neutral red assay and the condition index were used as biomarkers of the adverse biological effects. The PAH concentration in mussels at unimpacted sites, prior to deployment was ca. 100 microg kg(-1) but increased to 300 microg kg(-1) after three months at the contaminated site. Mussels transplanted to the uncontaminated site showed a decrease from 380 to 80 microg kg(-1). Significant changes in lysosomal stability occurred within one month of the beginning of the transposition; in contrast condition indexes were not correlated with the observed changes in PAH concentration.  相似文献   
95.
岳明新  赵恩好  张泉 《岩矿测试》2011,30(4):510-513
遵循《标准样品工作导则》GB/T 15000系列标准和YS/T 409—1998行业标准,研制了火试金用铅箔标准样品,样品加工厚度为0.1~0.2 mm,质量3 g,呈正方形。利用方差法对标准样品进行均匀性检验,并委托6家权威实验室采用火试金富集-原子吸收光谱法和电感耦合等离子体质谱法对金和银进行定值,用狄克逊法和夏皮罗-威尔克法检验分析数据。结果表明,研制的铅箔标准样品均匀性良好,金和银的标准值分别为0.011 g/t、0.313 g/t,定值结果准确;Au属于似正态分布,Ag属于正态分布。铅箔标准样品用于实验室火试金法分析金、银等贵金属矿物,效果良好,已经被批准为行业标准样品,编号为YSS045-2009。  相似文献   
96.
激光剥蚀电感耦合等离子体质谱(LA-ICP-MS)适合于直接分析硫化物矿物中痕量元素的含量及空间分布,但硫化物矿物的激光剥蚀特性与硅酸盐及氧化物不同,受到的干扰也更严重,且由于硫化物标准物质(尤其是含铂族元素、Au、Ag等贵金属元素标准物质)极度缺乏,限制了LA-ICP-MS技术在硫化物微区分析中的广泛应用。本文以贵金属标准样品GPT-9和矿石标准物质为原料合成锍镍试金扣,并封入真空管中重熔,利用背散射电子图像和LA-ICP-MS分析元素分布的均匀性,探讨真空重熔锍镍试金扣制备硫化物原位微区分析标准样品的可行性。背散射电子图像(BSE)显示真空重熔后锍镍试金扣由单相S、Ni化合物组成。LA-ICP-MS线扫描和点扫描分析表明,锍镍试金扣中S、Ni、Cr、Co、Cu、Pb、Sb、Cd、Bi等主量及微量元素分析精密度(RSD)均小于10%,均匀分布;在镍扣制备过程中Zn相对于Cu、Pb、Sb更难进入硫化物相;贵金属元素Au、Ag、Pt均一性较好,其余贵金属元素由于含量低、仪器波动及质谱干扰等影响因素造成分析数据的RSD相对较大,但可通过提高原料中贵金属元素含量、降低熔融样品淬火温度等方法进一步提高其均匀性。锍镍试金扣的组成元素对铂族元素分析的质谱干扰研究表明,重铂族元素(Os、Ir、Pt)和Au受到的干扰可忽略不计;轻铂族元素(Ru、Rh、Pd)受金属氩化物干扰较为严重,需进行干扰校正。研究认为,真空重熔技术可有效提高锍镍试金扣中各元素(包括贵金属)的均一性,达到硫化物原位微区分析标准样品的要求,利用真空重熔锍镍试金扣制备LA-ICP-MS原位微区痕量及贵金属硫化物分析标准样品具可行性。  相似文献   
97.
向明华  蒋昌华 《贵州地质》2007,24(2):154-155,153
由于成煤原始植物不同,成煤古地理环境各异以及地质造构运动等方面的影响,在特殊条件下,煤质化验数据会表现出异常的情况,通过数据审查,发现异常数据加以分析,对提高煤质报告的编制水平是十分必要的。  相似文献   
98.
吴东艳  周立志 《湖泊科学》2012,24(1):129-136
富营养化湖泊的蓝藻水华加剧了水体污染,影响湖泊生态系统的稳定.本研究针对安徽沿江富营养化程度不同的巢湖和菜子湖,2010年4--9月份,利用微核和彗星电泳实验检测水体污染物对克氏原螯虾(Procambarus clarkii)血细胞的微核率和DNA损伤,评价湖泊污染物的遗传毒性效应.巢湖和菜子湖细胞微核率最低值分别为0.316±0.131和0.243±0.063,最高值分别为0.624±0.136和0.360±0.081;巢湖DNA损伤三项指标TailDNA、TM和OTM最高值为7.59±1.58、2.75±1.55和3.12±1.45,菜子湖为5.02±1.42、1.07±0.16和1.19±0.26.两个湖泊克氏原螯虾血细胞微核率和DNA损伤都表现为随时间推移而增加,且巢湖6、7月份血细胞微核率和DNA损伤增加幅度最大.7、8、9三个月份,两湖泊细胞微核率和DNA损伤差异性达到极显著.彗星实验和微核实验结果一致,但前者更敏感.两种不同的遗传毒性检测方法结合能更好地检测污染物对机体产生的遗传毒性作用.  相似文献   
99.
李晓林  童纯菡 《岩矿测试》1998,17(3):167-171
采用镍锍试金预富集 中子活化分析方法,测定了大洋多金属结核标准物质GSPN 2、GSPN 3和深海沉积物标准物质GSMS 2、GSMS 3中的铂族元素;根据大洋样品成分特征,对常规的镍锍试金配方和熔炼条件作了改善;计算了活化分析中的铂族元素干扰核反应,校正了Au对Pt的二级干扰;选用羰基化镍粉配料,降低了铂族元素空白值。用国家一级标准物质GBW07102作了对照分析,结果与标准值相符。  相似文献   
100.
Evidence has been presented that a number of environmental agents perturbs the function of the sex hormone signalling pathways in marine animals.

In this work the estrogenic/antiestrogenic activity of coastal marine water samples from five sites of the Northern Mediterranean Sea was assayed using a recombinant Saccharomyces cerevisiae yeast strain (RMY326 ER-ERE) transfected with the human estrogen receptor . Extraction of potential EDCs from seawater was performed in columns packed with XAD-2 resins.

The estrogenic activity was calculated as percentage of the activity of 17β-estradiol (10 nM) and it ranged from 4.8% and 59.03%, significantly depending on sampling site (p = 0.0013) and season (p < 0.05). Antagonistic activity of extracts was also detected and the percentage of inhibition of estradiol-dependent β-galactosidase induction ranged to 52.8%. These results point the reliability of the yeast assay as a first level screening test to assess the quality of aquatic environments.  相似文献   

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