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精馏-膜分离集成过程与传统精馏工艺相比,因其具有明显节能降耗的经济性优势,故工业应用日渐增多,所以对其进行全面研究更有理论和实际意义。本文介绍了膜分离的机理模型,根据膜的亲水性和亲有机性对膜材料进行分类,总结了精馏-膜分离集成过程的理论研究方法,并分别从脱水和脱有机物两方面介绍了精馏-膜分离集成过程的主要实验研究及工业应用研究进展。通过对现有研究分析发现,目前该集成过程在膜材料和集成优化理论研究方面存在一定局限性,使其未能在工业上得以广泛推广应用。基于上述全面分析,提出了一定改进思路。 相似文献
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Tianchong Zhang Futing Yi Bo Wang Jing Liu Marina Ashmkhan Xinshuai Zhang 《Microsystem Technologies》2014,20(10-11):2005-2010
Micro pore optics (MPO) as an X-ray imaging system is perfectly suited for the applications in space telescopes due to its light-weight and high-resolution properties. We report the fabrication of MPO samples by LIGA process focusing on its sidewall surface used as mirrors for X-ray reflection. An intermediate mask is fabricated and used to obtain the working mask in order to avoid the UV exposure to a very thick photo resist layer. Around 400 μm-thick nickel MPO plate is obtained with the aspect ratio of the square pore and sidewall of 8 and 32, respectively. The root mean square roughness of the sidewall surface is below 10 nm in a 5 × 5 μm2 region. Some striations are found on the sidewall surface originating from the jagged edge of the chromium coating on the UV mask. 相似文献
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针对数字天顶仪原有方法计算过程复杂和计算过程中存在误差的问题,通过改变时间补偿方式和优化迭代核心,提出了一种改进的数字天顶仪定位方法.该方法在切平面中进行均值过程,消除了原方法运算中引入的误差,也避免了切平面变换和反变换的反复计算,从而大幅简化了计算流程.通过实验比较了传统方法与改进方法的计算效率和精度,结果表明:改进方法的计算效率比原方法提高了至少6倍;改进方法赤纬的计算精度比原来的15米左右提高了约1.05 m.因此,改进方法能够在一定程度上提高定位的精度. 相似文献
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Xiaowen Hu Xinmin Zhang Wenmin Yang Xiao-Fang Jiang Xinshuai Jiang Laurens T. de Haan Dong Yuan Wei Zhao Nan Zheng Mingliang Jin Lingling Shui Albertus P. H. J. Schenning Guofu Zhou 《应用聚合物科学杂志》2020,137(30):48917
A stable and scalable polymer-stabilized liquid crystal window which electrically switches from transparent to opaque has been fabricated. Scanning electron microscope measurement shows that higher polymer concentration will induce denser polymer network in polymer stabilized liquid crystal system and then stronger anchoring force between polymer network and liquid crystal molecules, which resulting in larger operating voltage. The cell with larger cell gap has a lower saturated transmittance in the voltage-on state, which attributed to a larger number of scattering domains in thick cell. The optimized cell exhibits a highly transparent voltage-off state (3.5% haze) and a voltage-on scattering state (98% haze) with the threshold voltage of around 20 V. The durability test shows that the optical device switches at least 100,000 times without degradation of optical contrast and shows a high temperature tolerance. Meanwhile, a 40 × 50 cm2 window has been developed in an industrial production line showing the same optical properties. Our results demonstrate the fabrication of smart windows with a highly transparent rest state and high optical contrast on a commercial mass production scale, making them attractive for applications in buildings, automobiles, and switchable sunglasses for light management and potentially energy saving. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48917. 相似文献
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比较8种大孔树脂对横山老黑豆酚类化合物的静态吸附和解吸特性,筛选出分离最佳的大孔树脂,分析静态吸附动力学曲线和最佳的乙醇解吸体积分数,优化不同的样品质量浓度和不同上样流速动态吸附工艺参数。HPLC方法确定8种酚酸含量以及5种异黄酮含量。结果表明,NKA-9大孔树脂的静态吸附和解吸对横山老黑豆酚类化合物的效果最好,静态吸附4 h可达到平衡,乙醇解吸体积分数为70%。动态吸附和解吸参数:样品上样质量质量浓度为1.96 mg/mL,上样流速为2.14 BV/h。HPLC分析和鉴定NKA-9大孔树脂分离纯化前后的横山老黑豆酚类物质种类没有变化,含量降低很少。横山老黑豆酚类物质中原儿茶酸、绿原酸、咖啡酸、大豆苷和染料木苷含量较高。 相似文献
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基于各向正交惩罚材料密度法法,建立了以自由阻尼结构模态阻尼比最大化为目标,以阻尼材料体积为约束条件,以阻尼材料单元相对密度为设计变量的拓扑优化数学模型。推导了模态阻尼比对阻尼单元相对密度的灵敏度和设计变量的更新准则,基于优化准则算法用MSC.Nastran的Direct Matrix Abstraction Program语言编制了通用的阻尼材料拓扑优化程序。以一铝板-声腔耦合系统为对象,以结构一阶弯曲模态阻尼比最大为目标,利用该拓扑优化程序和有限元分析方法对铝板上的阻尼材料进行优化布置,并用试验进行了验证。把铝板全阻尼处理和拓扑优化后部分阻尼处理的降噪效果进行对比,在仿真环境中,参考点处声压分别下降了110.6Pa和107.7Pa,在实验条件下,参考点处声压分别下降了22.47Pa和20.91Pa,从而验证了优化方法的有效性。 相似文献
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