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53.
鄂尔多斯盆地镇北地区三叠系延长组长8油组储层特征 总被引:1,自引:0,他引:1
鄂尔多斯盆地镇北地区延长组长8油层段是盆地重要的储集层之一。通过储层岩石学、储层物性、孔隙结构等方面对储层特征进行深入研究,研究结果表明,储层岩石类型主要为中细粒长石砂岩和岩屑长石砂岩,成分成熟度低,结构成熟度中—高;发育粒间孔隙、溶蚀孔隙、晶间孔等孔隙类型,喉道以中细喉—细喉为主。岩石物性总体较差,属低孔、低渗砂岩储层。研究结果对油田开发具有重要的指导意义。 相似文献
54.
本文提出一种能方便、快速、灵敏地检测水中苯胺类化合物的试剂盒。该方法是以N -氯代丁二酰亚胺和 8-羟基喹啉与苯胺的显色反应为基础。显色反庆所得的蓝绿色化合物的最大吸收波长为 6 1 0nm ,在苯胺为 0 .2~ 8mg/L的浓度范围内符合比尔定率 ,最低检出限为 0 .0 1mg/L ,测定的重现性在± 5 %以内。本方法已成功地用于环境水样的分析测定 相似文献
55.
Anindita Bhattacharyya 《Chemical engineering science》2004,59(21):4481-4492
An arbitrary flow of a viscous, incompressible fluid past a porous sphere of radius `a' with an impermeable core of radius `b', using Brinkman's equation in the porous region is discussed. At the interface of the clear fluid and porous region, stress jump boundary condition for the tangential stresses along with the continuity of normal stresses and the velocity components are used. On the surface of the impermeable core no slip condition is used. The corresponding Faxen's laws are derived to compute the drag and torque acting on the surface r=a. It is found that the drag and torque not only change with the change of the permeability, but also a significant effect of the stress jump co-efficient is observed. The variation of drag and torque with permeability for different thickness (a-b) of the porous region as well as for different values of stress jump coefficient is discussed when the basic flow is due to uniform flow, two dimensional irrotational flow, doublet in a uniform flow, stokeslet, rotlet. In case of uniform flow the flow field has been plotted. In all the cases, a significant effect of the stress jump coefficient has been realized. 相似文献
56.
论述了用于C8芳烃中二甲苯异构体以及乙苯分离的各种吸附分离技术进展,对各种工艺和特点以及工业应用状况进行了分析比较。详细介绍了目前国内C8芳烃吸附分离装置中的工业生产状况和面临的问题及挑战。提出应抓紧开发具有自主知识产权的C8芳烃吸附分离技术,尤其是开发一种对乙苯和二甲苯同时具有高选择性、高吸附能力、容易脱附的吸附剂,实现从C8芳烃中同时得到乙苯和二甲苯高纯度产品的目的,打破国外的技术垄断。 相似文献
57.
8-Hydroxyqunioline end-capped polystyrene was prepared through atom transfer free radical polymerization (ATRP) with 8-(5-chloromethyl) quinolyl acetate as initiator. The results indicated that this polymerization is a first order reaction with respect to monomer conversion. The molecular weight increased linearly with monomer consumption and very narrow distribution of molecular weight was obtained (polydispersity index less than 1.2). The FT-IR and NMR results show that the 8-hydroxyquinloine group was chemically bonded to the polymer end and there is nearly one 8-hydroxyquinoline group in per polymer chain. All those data show that polymerization of styrene at such conditions displayed living characters. The polymer with 8-hydroxyqquinoline end group reacted with triethylaluminum to form polymeric light-emitting complex and single layer LED was prepared by common spin-coating method. The peak wavelength of LED based on synthesized polymeric complex was around 570 nm. 相似文献
58.
A. El Ghazali S. Belcadi J. J. Rameau F. Dalard 《Journal of Applied Electrochemistry》1998,28(7):725-735
Electrosynthesis of peroxodiphosphate ions (P2O84–) was performed in 2m K3PO4, 1m K2HPO4 medium, using a platinum anode. The results showed that under conditions of potentiostatic polarization at constant potential, the reaction rate reaches a maximum value of 125mAcm–2 and a faradaic yield of 30%. From about 1.9V, the reaction kinetics are increasingly inhibited as the potential shifts positively. Rapid scanning potential voltammetry was used to characterize the oxidation state of the electrode surface. This method shows that the growth of (PtO) and (PtO2 or PtO3) oxides depend on the applied potential. It also establishes a correlation between the inhibition of P2O84– ion electrosynthesis and the oxide coating surface. When 2×10–3m KSCN is added to the solution, some oxygen evolution sites are selectively blocked and oxide occurs at more positive potential values. Consequently, the rate of peroxodiphosphate ion formation and the faradaic efficiency are increased to 380mAcm–2 and 75%, respectively. Under pulsed potential conditions it was possible to reach 1200mAcm–2 for P2O84– ion electrosynthesis with a faradaic yield of 82%. 相似文献
59.
Ni–W catalysts were prepared by impregnation of commercial -alumina and silica supports. The sulfidation, performed directly after drying at 100°C, yielded fully sulfided Ni–W species on both supports (SEM-EDAX, XPS, XRD). At optimal metals loading (50 wt% NiO + WO3, Ni/W = 2), the sulfided catalysts had similar texture (N2 adsorption) and displayed similar activity in dibenzothiophene hydrodesulfurization (DBT HDS), while the activity of the Ni–W/SiO2 catalyst in toluene hydrogenation (HYD) was six times higher than that of Ni–W/Al2O3. This is due to the more than two times higher WS2 slabs stacking number in Ni–W/SiO2 compared with Ni–W/Al2O3 (XRD, HR-TEM), yielding stronger adsorption of toluene (TPD). 相似文献
60.
Effects of allelochemicals on plant respiration and oxygen isotope fractionation by the alternative oxidase 总被引:8,自引:1,他引:8
The goal of this investigation was to determine the effects of allelochemicals on plant respiration that thereby may be responsible for their role in growth inhibition. We have tested the effects of juglone, quercetin, cinnamic acid, and-pinene on respiration rates, and electron partitioning through the cytochrome and alternative respiratory pathways, by measuring on-line oxygen consumption and oxygen isotope fractionation in soybean cotyledon tissue. Cinnamic acid and-pinene decreased the oxygen consumption rate and increased the relative partitioning of electron transport to the alternative pathway. Possible biochemical mechanisms of these effects are discussed. 相似文献