首页> 外文学位 >文献详情
【6h】

Mechanics of mass, energy and momentum transfer in complex textured materials at micro/nanoscales.

机译:在微米/纳米尺度上复杂质感材料中质量,能量和动量传递的力学。

获取原文
获取原文并翻译 | 示例
¥30

摘要

The aim of this work is the investigation of the physical properties associated with nanostructured materials for various advanced applications which include controlled drug release, pressure driven nanofluidics, spray cooling etc.;Polymer nanofibers (monolithic or core-shell) and turbostatic carbon nanotube bundles fabricated through electrospinning and co-electrospinning respectively were used as the key materials in this work. For controlled release applications, a model fluorescent dye Rhodamine 610 chloride, proteins, drugs or antigens encapsulated inside electrospun polymer nanofibers and its release to a buffer medium was analyzed. As a result of these experiments, it was discovered that the release process is limited by desorption process from nanopore surfaces. The experimental results were used as foundation as novel theory of release process and also allowed characterization of the relevant physical parameters of different compounds involved. In addition, thermal characterization of these electrospun polymer nanofibers was carried out to investigate their creep properties. The aim of this part was in the establishment of a detailed mechanism responsible for shrinkage of nanofiber mats at elevated temperatures and elucidation of its relation to the microscopic thermally-induced changes occurring in the polymer structure. In particular, thermal behavior of Poly(epsilon-caprolactone) (PCL), Poly(methylmethacrylate) (PMMA), Polyacrylonitrile (PAN) and Polyurethane (PU) in electrospun nanofibers and original pellets were studied using Differential Scanning Calorimetry (DSC) and linked to the onset of thermally-induced shrinkage of nanofiber mats.;The elctrospinning setup was then extended to Co-electrospinning process for fabricating Turbostratic Carbon Nanotube Bundles, for pressure driven flow of suspensions. Using a model water soluble compound, fluorescent dye Rhodamine 610 chloride, it was shown that deposit buildup on the inner walls of the delivery channels and its adverse consequences pose a severe challenge in implementing pressure-driven fluidic delivery through nano- and microcapillaries even in the case of homogeneous solutions.;The final work was in the investigation of the rheological properties of complex textured micro material, mainly gypsum slurries. Gypsum slurries experience rapid evaporation of water which causes them to solidify in a few seconds. It is therefore important to study their rheological properties for enhancing the efficacy of the production processes as well as to minimize the associated water content. Therefore, in this work, rheological characterization of gypsum slurries were studied under various initial conditions namely Water to Stucco Ratio, effect on rheological properties of the slurries due to the addition of foam and time related shear measurements.
机译:这项工作的目的是研究与各种先进应用相关的纳米结构材料的物理性能,包括控制药物释放,压力驱动的纳米流体,喷雾冷却等;制造的聚合物纳米纤维(整体式或核壳式)和静压碳纳米管束通过静电纺丝和共静电纺丝分别作为这项工作的关键材料。对于控释应用,分析了模型荧光染料若丹明610氯化物,包裹在电纺聚合物纳米纤维内部的蛋白质,药物或抗原,并将其释放到缓冲介质中。这些实验的结果发现,释放过程受到纳米孔表面解吸过程的限制。实验结果被用作新的释放过程理论的基础,并允许表征所涉及的不同化合物的相关物理参数。此外,对这些电纺聚合物纳米纤维进行了热表征,以研究其蠕变性能。该部分的目的是建立详细的机制,该机制负责在升高的温度下使纳米纤维垫收缩,并阐明其与聚合物结构中发生的微观热诱导变化的关系。尤其是,使用差示扫描量热法(DSC)研究了电纺丝纳米纤维和原始颗粒中的聚ε-己内酯(PCL),聚甲基丙烯酸甲酯(PMMA),聚丙烯腈(PAN)和聚氨酯(PU)的热行为,并进行了关联;然后将电纺丝装置扩展到共电纺丝工艺,以制造涡轮层状碳纳米管束,以压力驱动悬浮液流。使用模型水溶性化合物荧光染料若丹明610氯化物,结果表明,沉积物堆积在输送通道的内壁上,其不利后果对通过纳米和微毛细管实现压力驱动的流体输送提出了严峻的挑战,即使在纳米管中也是如此。最后的工作是研究复杂纹理的微材料,主要是石膏浆料的流变性能。石膏浆料会经历水的快速蒸发,这导致它们在几秒钟内固化。因此,重要的是研究它们的流变性质,以提高生产过程的效率以及使相关的水含量最小化。因此,在这项工作中,研究了在各种初始条件下石膏浆料的流变特性,即水灰泥比,由于添加泡沫而对浆料流变性的影响以及与时间有关的剪切测量。

著录项

  • 作者

    Raman, Srikar.;

  • 作者单位

    University of Illinois at Chicago.;

  • 授予单位 University of Illinois at Chicago.;
  • 学科 Engineering, Mechanical.;Nanotechnology.
  • 学位 Ph.D.
  • 年度 2010
  • 页码 191 p.
  • 总页数 191
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 TP7;
  • 原文服务方 国家工程技术数字图书馆
  • 关键词

    ;

相似文献

  • 外文文献
站内服务

联系方式:18141920177 (微信同号)

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号