滨海超深软土刚性桩复合地基工作性能研究

滨海地区深厚软土地基沉降控制是工程建设的关键.本文以珠海航空新城某近海市政道路工程为依托,对超深软土刚性桩复合地基工作性能进行了研究,研究结果表明:(1)采用等效桩墙简化的平面应变模型可以有效模拟刚性桩复合地基的受力及变形;(2)持力层沉降占地基总沉降比例超80％,当边桩桩间距较大时,最大沉降及最大桩-土差异沉降均发生...     

静电纺PLA微/纳米纤维膜的浸润性能研究

采用静电纺丝技术制备聚乳酸(PLA)微/纳米纤维膜,研究了其可纺性、浸润性能及结构。结果表明:以二氯甲烷为溶剂的PLA电纺丝溶液,当PLA质量分数为7%时,可纺出纤维直径为280～690 nm的PLA微/纳米纤维膜。PLA微/纳米纤维膜与水的接触角为127.6°,高于PLA流延膜与水的接触角107.7°;红外光谱分析表明,PLA微/纳米纤维膜的分子组成没有发生变化;X光电子能谱测试表明PLA微/纳米纤维膜的表面碳氧含量比高于PLA流延膜,PLA微/纳米纤维膜的疏水性得到提高。     

地铁联络通道人工冻结法的数值模拟分析

以冻结管间距为0.3、0.4、0.5 m及其相应间距的单双排布置作为主要变量,考虑土的比热容、密度以及导热系数,建立热传递有限元模型对冻结法施工的积极冻结过程以及融化过程进行数值模拟。研究表明:当冻结管采用间距为0.3 m布置时,双排管会比单排管的制冷效果更加明显。同时发现冻结管间距越密集制冷效果会越高,从经济上考虑,冻结管的布置形式可以采用间距为0.4 m双排布置。在隧道中心竖向位置处,距离地表面越近,受到冻结后土体竖向产生的位移越大,在冻结帷幕内的冻土位移不随深度的变化而变化;在地表面距离隧道中心水平距离越大的位置,受冻土膨胀产生的竖向位移越小,在隧道中心处位移最大,同时发现地表水平方向的径向位移变化并不明显。     

基于QPSO的震动传感器片上相位补偿器设计方法

震动传感器的系统相位非一致性会对地震波到时时差提取产生很大的误差,严重影响震源定位精度;针对这一问题,提出了一种基于量子粒子群优化算法（QPSO）的震动传感器片上相位补偿器设计方法。首先对震动传感器进行相位标定,获得传感器与参考传感器的相位差;其次设计基于QPSO算法的相位补偿滤波器对相位差进行修正,使其无限趋近于0;最后,将相位补偿滤波器封装成FPGA软核部署于FPGA上,完成对震动传感器的相位片上实时补偿。为了验证该方法的性能,将相位补偿滤波器部署于自研的多通道震动信号采集系统上,对8个相同型号震动传感器进行相位一致性校准。试验结果表明,在震动传感器频响范围内,该方法可以将2.5°内的传感器相位差实时修正至0.0044°以下,实现了震动传感器阵列的相位一致性实时校准。该成果在地下浅层震源定位领域具有较强的应用价值。     

多变量预估控制技术在聚丙烯装置上的应用

介绍了多变量预估控制技术在长盛石化聚丙烯装置的设计、开发过程以及多变量预估控制器的运行情况和应用效果,证明了应用该技术的系统增强了装置的抗干扰能力,提高了装置生产的平稳性,减轻了操作负荷和能耗,增加了装置效益,改变了传统的生产模式。     

高透氧软性角膜接触镜研究进展

基于硅水凝胶材料的高透氧软性角膜接触镜是最新一代的接触镜,可以满足消费者连续配戴的要求,同时可以消除因配戴接触镜引起的缺氧相关症状。硅水凝胶能很好平衡光学性质、透氧性、含水量和机械强度等本体性质。回顾了大量文献和专利,从本体材料角度,综述了高透氧软性接触镜的研究现状。     

Absorption of Low Concentration Sulfur Dioxide Using Liquid-containing Microporous Membrane

The absorption of low concentration SO2 in flue gas by using the module of liquid-containing microporous membrane which is made up of hollow fiber and citric acid-sodium citrate buffer solution was investigated. The absorption efficiency of hydrophilic and hydrophobic membranes by using the concept of dynamic contact angle was mainly studied. The influences on absorption efficiency from absorption time, flowrate of gas phase, SO2 concentration of gas phase, air pressure, citrate concentration, pH value of solution as well as the generation of sulfate radical in absorption solution were examined. The results indicate that the hydrophobic hollow fiber membrane is better than hydrophilic membrane, the absorption efficiency decreases with increasing absorption time, gas phase flowrate, gas phase SO2 concentration and air pressure, the absorption rate and capacity of SO2 can be improved by increasing the citrate concentration, the absorption efficiency can be improved by increasing the pH value of citrate solution, the concentration of SO42- in absorption solution increases linearly with the absorption time at a rate around 0.192 g/(L×h).     

The Therapeutic Potential of Exosomes in Soft Tissue Repair and Regeneration

Soft tissue defects are common following trauma and tumor extirpation. These injuries can result in poor functional recovery and lead to a diminished quality of life. The healing of skin and muscle is a complex process that, at present, leads to incomplete recovery and scarring. Regenerative medicine may offer the opportunity to improve the healing process and functional outcomes. Barriers to regenerative strategies have included cost, regulatory hurdles, and the need for cell-based therapies. In recent years, exosomes, or extracellular vesicles, have gained tremendous attention in the field of soft tissue repair and regeneration. These nanosized extracellular particles (30–140 nm) can break the cellular boundaries, as well as facilitate intracellular signal delivery in various regenerative physiologic and pathologic processes. Existing studies have established the potential of exosomes in regenerating tendons, skeletal muscles, and peripheral nerves through different mechanisms, including promoting myogenesis, increasing tenocyte differentiation and enhancing neurite outgrowth, and the proliferation of Schwann cells. These exosomes can be stored for immediate use in the operating room, and can be produced cost efficiently. In this article, we critically review the current advances of exosomes in soft tissue (tendons, skeletal muscles, and peripheral nerves) healing. Additionally, new directions for clinical applications in the future will be discussed.     

Lipid biophysics and/or soft matter-inspired approach for controlling enveloped virus infectivity

Proven as a natural barrier against viral infection, pulmonary surfactant phospholipids have a biophysical and immunological role within the respiratory system, acting against microorganisms including viruses. Enveloped viruses have, in common, an outer bilayer membrane that forms the underlying structure for viral membrane proteins to function in an optimal way to ensure infectivity. Perturbating the membrane of viruses using exogenous lipids can be envisioned as a generic way to reduce their infectivity. In this context, the potential of exogenous lipids to be used against enveloped virus infectivity would be indicated by the resulting physical stress imposed to the viral membrane, and conical lipids, i.e. lyso-lipids, would be expected to generate stronger biophysical disturbances. We confirm that when treated with lyso-lipids the infectivity three strains of influenza virus (avian H2N3, equine H3N8 or pandemic human influenza H1N1) is reduced by up to 99% in a cell-based model. By contrast, lipids with a similar head group but two aliphatic chains were less effective (reducing infection by only 40–50%). This work opens a new path to merge concepts from different research fields, i.e. ‘soft matter physics'' and virology.     

制浆蒸煮过程卡伯值测定的研究

采用RBF-CSR方法测定卡伯值，CSR方法将从自变量参数矩阵和因变量向量中提取成分，循环地构造并扩张Krylov子空间，且以此作为源空间，运用最小二乘淮则解得映射到因变量实空间的线性泛函。整个求解过程包括了最小二乘回归（LSR），主成分回归（PCR），偏最小二乘回归（PLS）及其他中间回归方法。然后由预报能力的强弱，从中确定最佳回归模型。通过实验表明，采用该方法测定制浆蒸煮过程卡伯值，效果良好。