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91.
渗透率是反映储层渗流能力的重要参数,目前对于单一储层的渗透率表征方法,通常是在岩心分析渗透率或测井解释渗透率的基础上进行厚度加权算术平均。这种方法对于均质的储层来说是适用的,但对于非均质严重的储层,不能准确反映该储层的实际渗流能力。本文提出一种应用可动流体体积权衡表征渗透率的方法,经实际资料验证,能较好地反映储层的实际渗透能力。 相似文献
92.
Sumathy Arumuganathar Scott Irvine Jean R. McEwan Suwan N. Jayasinghe 《应用聚合物科学杂志》2008,107(2):1215-1225
In a recent discovery, coaxial electrospinning was explored to encapsulate living organisms within a continuous bio‐polymeric microthread from which active biological scaffolds were fabricated (Townsend‐Nicholson and Jayasinghe, Biomacromolecules 2006, 7, 3364). The cells were demonstrated to have gone through all expected cellular activity without their viability being compromised. These biologically active threads and scaffolds have direct and tremendous applicability from regenerative to therapeutic medicine. Currently these post‐processed cells as composite threads and scaffolds are being investigated in‐depth at a cellular level to establish if the processing methodology has any affect on the cellular make‐up. We now demonstrate a competing non‐electric field driven approach for fabricating composite threads and scaffolds influenced only by a differential pressure. We refer to this novel composite thread to scaffold fabrication methodology as coaxial aerodynamically assisted bio‐threading (CAABT). Our investigations firstly, demonstrate that this technique can process handle living organisms without biologically perturbing them in anyway. Secondly the process is elucidated as possessing the ability to form composite active threads from which biologically viable scaffolds are formed. Finally our study employs florescent activated cell sorting (FACScan), a method by which the cellular dynamics and viability are quantified on control and threaded cellular samples at two prescribed time points. In parallel with FACScan, optical comparison of cellular morphology at three time points within a period of three weeks is carried out to photographically observe any changes in the post‐processed cellular phenotype. Our developmental investigations into this novel aerodynamically assisted threading methodology has unearthed a unique biomicrofabrication approach, which joins cell electrospinning in the cell threading to scaffold fabrication endeavor. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
93.
A. Mounir EL Sayed A. Yamauchi N. A. Darwish A. A. Abd EL‐Mageed S. F. Halim 《应用聚合物科学杂志》2008,109(5):2988-2993
The charged mosaic polymer membrane (CMM) without reinforcement and the composite charged mosaic polymer membrane (CCMM) with reinforcement were investigated in terms of salt and water transport (permeability). The composite charged mosaic polymer membrane (CCMM) with reinforcement showed a unique transport behavior such as preferential material transport Lp and ω. Water permeability coefficient, Lp and salt permeability coefficient, ω were estimated by taking account of active layer thickness of composite polymer gel. The Lp and ω values of CCMM with reinforcement were larger than those of CMM without reinforcement. On the other hand, the reflection coefficient of CCMM, σ, showed negative value, which suggested preferential material transport to solvent transport. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
94.
Effect of Li+ ions on structure,properties, and actuation of cellulose electro‐active paper actuator
We have reported an electro‐active paper actuator from regenerated cellulose. After dissolving cellulose fibers with a solution of lithium chloride in N,N‐dimethylacetamide, cellulose was regenerated by combining distillation of cellulose solution along with washing with the mixture of deionized water, isopropyl alcohol, and running water. However, the effect of Li+ ions on structure, properties, and the actuation behavior of the actuator was not studied. This article describes the changes in these parameters when the Li+ ions are removed by subjecting it to different running water exposure time. The structure and properties of cellulose electro‐active paper and its actuation behavior were studied. As Li+ ions content reduced from 4354.17 to 10.26 ppm by increasing the exposure time of running water, crystallinity, Young's modulus, and bending displacement decreased. Details about the investigation have been explained. This elimination of ions is important to increase the piezoelectric effect in EAPap by decreasing the ion migration effect. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008 相似文献
95.
介绍光电被动感应控制开关模块工作原理,研究开发了一种基于被动感应控制原理的自动冲水控制装置,总结比较了主动感应控制与被动感应控制的优缺点及其应用特点。 相似文献
96.
电流变体特性及电流变体应用器件的进展 总被引:2,自引:0,他引:2
本文详细评述了电流变体(ERF)材料的组成、工作机理及其流变力学性能,提出以Bingham塑性体来近似描述电流变体的流变特性,综述了电流变体在智能材料、汽车离合器、液压阀门等器件中的应用,给出了含电流变体的双层智能复合材料梁单层、双层加电状态对其振动特性的影响,设计了含电流变体的主动控制式减振器,并对其在外加电场作用下的减振性能进行了评价。 相似文献
97.
Fischer-Tropsch synthesis on Fe-Mn ultrafine catalysts 总被引:2,自引:0,他引:2
The Fischer-Tropsch (FT) synthesis on Fe-Mn ultrafine catalysts prepared by a special degradation method of Fe-Mn complexes is presented. The effects of preparation method and Mn content on the FT performance are examined and the active phases and the role of Mn are elucidated. 相似文献
98.
对具有结构不稳定性的有源滤波器的非线性问题进行了研究,通过对绝缘栅双极型晶体管(IGBT)器件开关过程产生的瞬态电流脉冲的传播过程进行分析,将IGBT器件的控制电压引起的结构稳定问题的抑制转化为该瞬态电流脉冲传播通路的阻断。利用仿真和实验对正激式与反激式开关变换器进行抗干扰能力的研究,说明反激式开关变换器用于有源电力滤波器(APF)的辅助开关电源,更有利于APF对非线性问题的抑制。 相似文献
99.
100.
Athanasios Eftaxias Josep Font Agusti Fortuny Azael Fabregat Frank Stüber 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(6):677-687
The wet air oxidation of phenol over a commercial active carbon catalyst was studied in a trickle bed reactor (TBR) in the temperature and oxygen partial pressure ranges of 120–160 °C and 0.1–0.2 MPa, respectively. The performance of the active carbon was compared in terms of phenol and COD destruction. The weight change of active carbon due to reaction was also measured. Finally, oxic phenol adsorption isotherms were assessed in batch conditions at 25, 125 and 160 °C. In order to use the conversion data obtained from the TBR for a kinetic study, special care was taken to check the kinetic control in the TBR experiments. Several kinetic models including power law or Langmuir–Hinshelwood expressions were considered to describe the catalytic oxidation of phenol over active carbon. The simple power law model with first order dependence on both phenol and oxygen concentration predicted satisfactorily the experimental data not only over the entire range of operating conditions studied, but also outside its validity range. Copyright © 2005 Society of Chemical Industry 相似文献