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81.
介绍了Delta4型压力筛生产全漂白硫酸盐法马尾松浆的运行情况,对存在的问题进行分析探讨,并对比了技改重新选型后的生产情况。 相似文献
82.
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
83.
Burns G. Leonard; Gomez Rapson; Walsh James A.; de Moura Marcela Alves 《Canadian Metallurgical Quarterly》2003,15(1):118
G. J. DuPaul (see record 2003-02033-012) offered two suggestions for additional research to understand the strong source effects reported by R. Gomez, G. L Burns, J. A. Walsh, and M. A. de Moura (see record 2003-02033-001) in attention-deficit/ hyperactivity disorder (ADHD) rating scales. The first suggestion was to determine whether the source effects represent mostly bias or accuracy. The second suggestion was to minimize source effects through the development of better ADHD rating scales. Because source effects can represent bias or accuracy, it is important to minimize the bias aspect through content validation procedures prior to attempts to determine whether source effects better reflect bias or accuracy. This comment offers various suggestions to reduce the bias in ADHD rating scales. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
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
85.
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
86.
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
87.
88.
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
89.
详细介绍了ZPG系列盘式真空过滤机的主要特点、基本原理和主要技术参数。对盘式真空过滤机的过滤理论进行了系统的研究 ,以及为提高过滤系数和降低滤饼水分所采取的关键措施。与传统的真空过滤机进行了对比 ,表明ZPG系列盘式真空过滤机的滤饼水分可以降低 1 %~ 3 % ,过滤系数提高 3 0 %~5 0 % ,过滤每吨精矿的能耗可以降低 5 0 %左右 ,使得ZPG系列盘式真空过滤机在国内各大冶金矿山得到全面推广使用 ,创造了巨大的经济效益和社会效益。 相似文献
90.
The reversible persistent changes of the fill factor (FF) induced by the illumination and voltage bias along with changes in the electronic properties of the ZnO/CdS/Cu(In,Ga)Se2 photovoltaic devices have been studied. Admittance spectroscopy and capacitance–voltage characterization reveal a correlation between the FF and the space charge distribution within the absorber. Our experiments provide evidence that a major source of FF loss in efficient devices is caused by excess negative charge close to the interface. We explain the persistent changes in the net acceptor concentration in the interface region by the relaxation effects due to compensating donors—the same mechanism, which leads to metastable changes of the doping level in the bulk of the absorber. 相似文献