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101.
Li Song Jiaxiang Lin Yang He Jingqing Li Jing Sheng Shichun Jiang Dinghai Huang 《Journal of Polymer Science.Polymer Physics》2019,57(6):323-330
In the lower critical solution temperature phase separation of poly(vinyl methyl ether) aqueous solutions, the process corresponding to the weakening of the hydrogen bond interaction with increasing temperature is dominant and occurs over the entire concentration region of solutions and over a broad temperature range from 30 to 41°C, giving rise to the energetic enthalpic effect during phase separation, while the conformational change, that is, collapse of the swollen polymer coils, occurs only in the swelling polymer solution when the water concentration is above 38.3 wt %, giving rise to the entropic effect during phase separation. In addition, the entropic process corresponding to the collapse of the polymer coils occurs in a much narrow theta temperature range from 35.5 to 37°C. If the solution is held at a constant temperature for a sufficiently long time, 90% collapse of the polymer coils occurs in only the 0.5 °C temperature region between 35.5 and 36°C. Accordingly, in the enthalpic process, the most dramatic blueshift of the νC‐O bond peak occurs in the temperature range between 35 and 41°C, while this blueshift is only approximately 2 cm?1 in the temperature range from 30 to 35°C, prior to the collapse of the polymer coils due to the entropic effect. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 323–330 相似文献
102.
Inertial microfluidics has attracted significant attentions in last decade due to its superior advantages of high throughput, label- and external field-free operation, simplicity, and low cost. A wide variety of channel geometry designs were demonstrated for focusing, concentrating, isolating, or separating of various bioparticles such as blood components, circulating tumor cells, bacteria, and microalgae. In this review, we first briefly introduce the physics of inertial migration and Dean flow for allowing the readers with diverse backgrounds to have a better understanding of the fundamental mechanisms of inertial microfluidics. Then, we present a comprehensive review of the recent advances and applications of inertial microfluidic devices according to different channel geometries ranging from straight channels, curved channels to contraction-expansion-array channels. Finally, the challenges and future perspective of inertial microfluidics are discussed. Owing to its superior benefit for particle manipulation, the inertial microfluidics will play a more important role in biology and medicine applications. 相似文献
103.
通过压强变化时显示屏上干涉条纹出现或者消失的数量,迈克尔逊实验仪可以测定空气的折射率。实验中测量的物理量较多,人工处理数据比较繁琐,且容易出错,因此使用Matlab软件处理数据可以直接得到不同气压的空气的折射率,处理过程快捷精确。Matlab软件处理数据时,对实验数据进行了最小二乘法处理,可以得到空气折射率随气压变化的拟合直线。 相似文献
104.
对于图G上热方程(△-/t-q)u=0的正解u=u(x,t),得到图上改进的Li-Yau梯度估计不等式,这里q满足Γ(q)≤η~2,η是一个常数,进而得到改进的Harnack型不等式,推广了以前的结果. 相似文献
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107.
Jiaxiang Cai 《Journal of Computational and Applied Mathematics》2010,234(3):899-905
In this paper, we derive a new 10-point multisymplectic scheme for the modified regularized long-wave equation. The new scheme is an explicit scheme in the sense that the third time level does not include nonlinear terms. Numerical results indicate that the new scheme not only provides satisfied numerical solutions, but also preserves three invariants of motion very well. 相似文献
109.
为实现铝箔板厚度的精确控制,采用了西门子S7-400PLC为核心的AGC系统,同时把模糊PID控制原理应用于某铝厂的铝箔板厚度控制系统,获得了理想的效果。详细阐述了AGC的工作原理、系统硬件和软件设计。实践表明,系统的轧制精度得到有效的提高,性能指标满足了生产的需要。 相似文献
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