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101.
关于SBR工艺的书籍和文章很多。本文在这些资料的基础上整理总结 ,对经典SBR工艺的应用进行了综述 ,归纳了经典SBR工艺的特点 ,介绍了各种新型SBR工艺。 相似文献
102.
Palogue油田复合油藏动态响应及特征描述 总被引:1,自引:1,他引:0
以简单的复合油藏模型理论和方法为基础,以Palogue油田的实际测试井为例,介绍了复合油藏模型的试井动态识别与模型拟合,及与地质静态资料相结合的油藏综合描述过程.该描述方法将会对实际试井解释和油藏综合描述工作有所借鉴和帮助. 相似文献
103.
David M. Scott Debendra K. Das Vijayagandeeban Subbaihaannadurai 《Petroleum Science and Technology》2006,24(8):895-909
A finite element scheme is presented to model the dissociation of gas hydrates in porous media by hot water injection. We show a complete derivation of the finite element formulation, including the associated mass and energy conservation equations capable of performing transient analysis of both conductive and convective heat transfer for gas and liquid flow in porous media. The scheme also includes the latent heat effect to accommodate the change of phase due to melting of hydrate. In the companion paper, Part II, this method is successfully applied to hydrate reservoirs. 相似文献
104.
建立了斜拉桥动力分析的三维有限单元模型 ,研究了单元类型和参数变化对斜拉桥动力特性的影响。详细地讨论了斜拉桥非线性来源 ,并运用 6节点薄壁单元和 4节点索单元分别考虑了斜拉桥弯曲构件和索的非线性特性。通过对一斜拉桥的数值分析 ,得到了关于斜拉桥动力参数敏感性的一般结论。 相似文献
105.
106.
J. Gajdoš Kljusurić 《Sadhana》2003,28(6):991-998
This work is an experimental study of the differential scanning calorimetry characterisation of polymer materials used in
food packaging materials, such as polypropylene (0.03 mm), polyethylene (0.1 and 0.03 mm), poly(D-(-)-Β-hydroxybutyrate) (powder),
two-layered polypropylene (0.064 mm), and two-layered polypropylene with poly-vinylidene-chloride (0.012/0.021). The polymer
stability was checked by simulation of conditions during food preparation in microwave ovens, sterilisation or rapid freezing.
The materials were tested in the temperature range from 40 to 200‡C at different scan rates from 2 to 30°C min−1 during heating or cooling. The enthalpies show a high correlation coefficient (0.964) with scan rate. All samples undergo
phase change in the temperature range from 107 to 173°C during heating and enthalpies are in the range from 31.8 to 71.1Jg−1. Upon subsequent cooling from 200°C, the temperature range of phase changes is shifted to lower temperatures from 86 to 102°C
with enthalpies ranging from 30.4 to 57.8 J g−1.
Experiments with exposure of polymers to microwave radiation and freezing prove that the phase change considering the temperature
range is very similar in all experiments. 相似文献
107.
Kevin E. Spaulding Geoffrey J. Woolfe Rajan L. Joshi 《Color research and application》2003,28(4):251-266
Image sources, such as digital camera captures and photographic negatives, typically have more information than can be reproduced on a photographic print or a video display. The information that is lost during the tone/color rendering process relates to both the extended dynamic range and color gamut of the original scene. In conventional photographic systems, most of this additional information is archived on the photographic negative and can be accessed by adjusting the way the negative is printed. However, most digital imaging systems have traditionally archived only a rendered video RGB image. As a result, it is not possible to make the same sorts of image manipulations that historically have been possible with conventional photographic systems. This suggests that there would be an advantage to storing images using an extended dynamic range/color gamut color encoding. However, because of file compatibility issues, digital imaging systems that store images using color encoding other than a standard video RGB representation (e.g., sRGB) would be significantly disadvantaged in the marketplace. In this article, we describe a solution that has been developed to maintain compatibility with existing file formats and software applications, while simultaneously retaining the extended dynamic range and color gamut information associated with the original scenes. With this approach, the input raw digital camera image or film scan is first transformed to the scene‐referred ERIMM RGB color encoding. Next, a rendered sRGB image is formed in the usual way and stored in a conventional image file (e.g., a standard JPEG file). A residual image representing the difference between the original extended dynamic range image and the final rendered image is formed and stored in the image file using proprietary metadata tags. This provides a mechanism for archiving the extended dynamic range/color gamut information, which is normally discarded during the rendering process, without sacrificing interoperability. Appropriately enabled applications can decode the residual image metadata and use it to reconstruct the ERIMM RGB image, whereas applications that are not aware of the metadata will ignore it and only have access to the sRGB image. The residual image is formed such that it will have negligible pixel values for those portions of the image that lie within the sRGB gamut, and will therefore be highly compressible. Tests on a population of 950 real customer images have demonstrated that the extended dynamic range scene information can be stored with an average file size overhead of about 8% compared to the sRGB images alone. © 2003 Wiley Periodicals, Inc. Col Res Appl, 28, 251–266, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.10160 相似文献
108.
在分析一类离散事件动态系统的运行周期性及稳定性时,必须求解极大代数意义下矩阵的特征值。这一直被认为是十分困难的工作。直至目前为止,尚无一种能确定任一方阵全部特征值及特征向量的简易方法。本文对极大代数意义下任一方阵的幂矩阵的周期性特征进行了深入分析。本文的结果为寻求计算特征值及特征向量的新算法提供了十分有效的途径。 相似文献
109.
聚氨酯/聚(甲基丙烯酸甲酯-甲基丙烯酸丁酯)互穿聚合物网络聚合物的阻尼性能 总被引:7,自引:0,他引:7
采用本体聚合法合成出一系列阻尼性能良好的聚氨酯/聚(甲基丙烯酸甲酯-甲基丙烯酸丁酯)(PU/P(MMA-BMA))互穿聚合物网络(IPN)聚合物,通过动态力学分析方法表征了PU/P(MMA-BMA)IPN聚合物的阻尼性能。探讨了加入催化剂、高温后处理、交联剂用量及PU与P(MMA-BMA)的质量比对PU/P(MMA-BMA)IPN聚合物阻尼性能的影响。实验结果表明,经高温后处理后,以二月桂酸二丁基锡为催化剂、交联剂二乙烯基苯用量(占MMA和BMA的摩尔分数)为1.5%、PU与P(MMA-BMA)的质量比接近1或小于1时,PU/P(MMA-BMA)IPN聚合物具有良好的阻尼性能。 相似文献
110.
LiNi0.5Mn1.5O4 powder was synthesized via sol-gel method and coated with ZnO in order to test the electrochemical cyclability of the material as a cathode for the secondary Li battery in the 5 V range at 55 °C. The ZnO-coated LiNi0.5Mn1.5O4 powder nearly maintained its initial capacity of 137 mA h g−1 after 50 cycles whereas the uncoated powder was able to retain no more than 10% of the initial capacity after 30 cycles. TEM analysis of the cycled cathodes suggests that the formation of the graphitic surface phase, hindering the Li migration, may be responsible for the rapid capacity loss of the uncoated material while no such phase was observed on the surface of the ZnO coated LiNi0.5Mn1.5O4 powder. 相似文献