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排序方式: 共有141条查询结果,搜索用时 31 毫秒
81.
82.
多相流动测井数据的预处理方法及软件研制 总被引:1,自引:1,他引:1
通过测井曲线平滑处理和深度校正,对生产测井资料进行了预处理。采用VisualC++及与其兼容的C语言开发的可视化程序实现了生产测井资料的预处理功能,并且多相流动测井数据预处理的软件化为以后的解释工作提供了方便。实际测井资料解释试验表明,该方法应用于产液剖面测井资料解释,提高了解释的精度和可靠性。 相似文献
83.
氯化钙体系对松香废水的絮凝处理 总被引:2,自引:1,他引:2
黄国林 《华东地质学院学报》1997,20(4):396-400
本文报道了氯化钙和硫酸铝或聚丙烯酰胺组成的处理体系对松香废水进行的絮凝研究,全面分析了福建省南平林化厂废水的物质组成和污染指标。通过正交试验,确定处理的主要影响因素。结果表明,用该体系处理松香废水,比用单一絮凝剂,能更好地降低废水的化学耗氧量,树脂及色度,为治理松香废水提供了较充分的数据。 相似文献
84.
Ying FU Shuili YU 《中国地球化学学报》2006,25(B08):149-150
Chemical coagulation is very important in water treatment, in which coagulant is an essential part. Pre-polymerized Al^3+ and Fe^3+ products have been used in practice, continuously spread for many years. However, iron-based coagulant has become the focus of studies due to cumulative biologic toxicity of residual Al in treated water. Polyferric sulfate (PFS) and poly-silicic-ferric sulfate (PSF) are all pre-polymerized polymers of Fe^3+ salts. The hydrolysis process and species distribution of Fe^3+ ions have been investigated extensively by many chemists and water-treatment specialists. Generally, the coagulation mechanism of conventional or pre-polymerized coagulants was often studied through jar-test, absorption experiment, microstructure observation or hydrolysis species indirectly. However, few researches have been done on the hydrolysis process of PSF in detail and on the study of the coagulation mechanism using its hydrolysis species distribution until now. In this work, PSF was prepared using water glass, ferrous sulfate and sodium chlorate by a copolymerization method. The hydrolysis species distribution was theoretically derived from pH variation during hydrolysis process of PSF compared to that of polyferric sulfate (PFS), and then characteristics [morphology, species size, Zeta potential, spectra of X-ray diffraction and infrared spectra (IR)] and coagulation performances were explored between them. Coagulation mechanism was analyzed according to hydrolysis species distribution, characteristics and coagulation performances. The results showed that PSF gives different species distribution at different pH values and characteristics from those of PFS, leading to different coagulation mechanisms between the two coagulants. 相似文献
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86.
We consider the dynamic behavior of a large-scale, two-dimensional fibril fracture field embedded in a sedimentary pile which is resting on a tectonically active crustal basement. Fractures are treated statistically as a dilute gas composed of parallel, stressed fractures. The salient physical processes are annihilation/coalescence of fractures through binary collisions and their precipitation, diffusion, and advection caused by their motions. The analysis uses techniques of coagulation theory to follow evolution of fractures as they develop from small-scale, elementary ruptures (fibrils) to large-scale objects. The purpose is to study size distribution and temporal variations of emerging fractures at the sedimentary surface with fibril fractures throughout the sedimentary pile. Analysis suggests that transport and in situ coalescence/annihilation of fibril fractures through sediments may be responsible for the size spectrum and temporal variations observed in surface fractures and ruptures. We find that smaller-scale fractures advected to the sedimentary surface have a time lag relative to larger-scale precipitated fractures—suggestive of an after-shock type of behavior. We also find that annihilation reactions (approach to hydrostatic stress and/or cementation) can be effective in reducing the mean size of emerging fractures. Simple estimates indicate that if the annihilation rate is about 5–10 times the coalescence rate, then the coalescence process is virtually unable to produce any larger-scale fractures than the original elementary ruptures (fibrils). 相似文献
87.
Conventional methods of soil nitrogen extraction are time consuming, expensive and tedious. Remote sensing and Geographical Information System technologies can be used for the rapid and efficient prediction of the presence of soil nitrogen. However, studies are limited by and large to fields of larger and homogeneous units. This research concentrates on the prediction of topsoil nitrogen from harvested, scattered and small-sized agricultural fields of India using hyperspectral data. Spaceborne hyperspectral Hyperion data are used for the prediction of the presence of nitrogen. Multivariate partial least square regression method was used to predict the presence of nitrogen from reflectance. Reflectance data were pretreated using moving average and Savitzky–Golay filters which resulted in moderate prediction of R2 0.65 and 0.63 for calibration and validation, respectively. It can be inferred that Hyperion data can be effectively used for the prediction of the presence of soil nitrogen with a moderate level of accuracy even in case of scattered fields and fields of sizes approximately equal to the spatial resolution of the satellite. 相似文献
88.
混凝和膜分离联用处理制药废水二级出水中试试验 总被引:3,自引:2,他引:1
对东北制药总厂废水处理厂的二级出水采用混凝-超滤-反渗透膜工艺进行中试处理研究。试验结果表明:混凝工艺对浊度和COD的去除率分别在62.0%和22.3%以上;超滤工艺对浊度和COD的去除率分别在87.4%和54.5%以上;反渗透工艺产水脱盐率在97.6%以上。工艺出水满足循环用水水质指标,工艺运行稳定。 相似文献
89.
湖泊沉积物粒度分析前处理过程中絮凝现象的消除方法研究 总被引:1,自引:0,他引:1
采用激光粒度仪对湖泊沉积物进行粒度分析时需要进行必要的前处理.在有效去除有机质与碳酸盐颗粒的同时,需要消除细粒泥沙质样品中絮凝现象对粒度分析结果造成的误差或错误.本文以武汉三角湖表层沉积物样品为例,采用X射线粉晶衍射(XRD)对其矿物组成和粘土矿物种属进行鉴定,并采用全自动激光粒度仪对样品进行粒度分析.X射线粉晶衍射结果表明样品中非粘土矿物主要为石英与长石,粘土矿物以伊利石、高岭石、绿泥石为主;粒度分析结果显示样品中小于30μm组分占94.5%.这些特征表明该样品易于在前处理过程中形成絮凝.本次研究采用单因素寻优法探讨了超声震荡、分散剂、洗酸对于以伊利石、高岭石、绿泥石为主、平均粒径较小的样品消除絮凝现象的最佳条件.研究结果表明,针对此类样品消除絮凝现象的最佳条件为:超声震荡时间应选择6~8 min,分散剂浓度为20 g/L左右,同时在粒度分析之前需要对样品进行洗酸. 相似文献
90.