摘要： Artificial dewatering of shales is a method to eliminate shale related problems such as wellbore stability, swelling, and soil instability that produces landslides. In this dissertation, the semi-permeable membrane behavior of shale, permitting osmotic flux of fluid to the partial exclusion of ions, has been studied as a means to dewater shales exposed to chemical solutions with ion activities less than that of the in situ shale pore fluid. This dissertation examines the rich and complex physical-mechanical behaviors exhibited by shales when exposed to differing solutions over time, temperature, chemical, and stress conditions. Using several unique experimental designs and numerical modeling, this study advances the level of understanding of time dependent shale behavior arising from changes in clay mineral structure and crystalline phase. The flux of water and ions over time due to semi-permeable membrane properties of shale and very fine-grained material has been numerically modeled. The purposes of this model are to predict the flux of fluid and ions through natural geological fine-grained and clay-rich materials over time and to predict the effect of this flux on long-term shale membrane behaviors. The required input parameters for the model, including water activity of both interfacial chemical fluid and the pore-fluid of the membrane, membrane properties (reflection coefficient, porosity, hydraulic conductivity, mineral compressibility, diffusion processes), and temperature and pressure conditions, were determined by laboratory work on Pierre Shale using High-Temperature High-Pressure (HTHP) Shale Apparatus. Results of this model reveal that, due to the flux of solute through the semi-permeable membrane, the shale’s pore fluid activity will reduce through time, leading to a reduction in the ideality of the membrane. Given enough time (depending on the activity of the chemical used and the membrane thickness and permeability), the chemical and hydraulic differe

关键词： 微流体系统   无阀微泵   微流体数字化技术   泵送性能   生物制造   细胞支架   细胞输送  

摘要： 微泵是微流体系统的重要部件。主流微泵是基于容积式驱动技术发展的，其有阀型微泵，内部有可动件的阀体，微泵的可靠性和使用寿命不高;其扩张收缩管式无阀型微泵，反向止流性较差，不能实现单向流。基于其它驱动技术，如电渗式驱动、磁流体驱动技术的微泵，对所泵送的液体的适用性较差。所以，实现基于新的驱动技术，并对泵送液体无特殊要求，具有广泛适用性，内部无可动部件的微泵，是微泵送研究的重要课题。 本论文基于“微流体数字化”技术，充分利用微尺度特性，提出固液两相耦合驱动原理：在微尺度下，由外部作用，使固壁产生周期性的沿流向的小幅运动;由于边界流与固壁间的分子作用力，使边界流具有固体特性，所以边界流与固壁一起运动;边界流与中间流产生速度差势，由于液体间粘性力的作用，拖动中间流运动。 以此设计新型的非隔膜式的数字化无阀微泵。微泵两端呈针状，中间为腔体，进口端直径大于出口端直径。利用毛细作用力将液体吸入，再利用固液耦合作用驱动泵腔体内流体运动，由于进、出口端自锁，液体形成单向流，由出口端泵送出去，实现流体的微泵送。经建模分析，微泵的结构参数、固相运动参数以及液相粘性参数对流动产生影响，需要综合各参数，进行优化。 本论文针对玻璃成形特点，设计制作水平式微器件制备仪，并制作了成本较低的玻璃无阀微泵管。并进行原理性验证实验，证明原理正确，可实现泵送。针对不同的出口直径，微泵管的进、出口比率在适当的范围内，可实现泵送。 本论文的数字化无阀微泵可实现连续流、离散流的泵送。低频率驱动可泵送离散流，高频率驱动可泵送连续流。无阀微泵对泵送液体具有广泛的适用性。可泵送较低黏度液体，如蒸馏水、酒精;也可泵送较高粘度的酸奶;还实现了银粉悬浊液的泵送，没有沉积或堵塞现象;对含细胞的培养液也实现了培养液包裹细胞同时的单个的泵送。无阀微泵泵送液体量微小、单次离散泵送可达皮升级;泵送体积流速可控制得很小，经测量，可达0.541μL／min，甚至更小;泵送效率较高，泵送的出口速度可达0.2m／s。 结合生物制造中的应用研究，利用无阀微泵将细胞向组织支架上进行定点输送，摸索多种细胞在组织支架上的培养的可能性。运用微立体光刻技术，设计、制备初步的微米级的圆柱阵列式和三角孔式细胞支架，支架结构微小，支架孔径约为100-150μm，可作为原生代种子细胞的附着处，支架内部有营养存储空间和流动通道。选用虾卵、小鼠卵细胞实验，该无阀微泵可利用毛细作用力，将含有细胞的培养液连同细胞一起吸入微泵管内，并可将细胞定点输送到指定的支架微孔内，并能保持生物活性。此方法为三维空间多种细胞排列生长提供一种思路。

关键词： 铅锌矿床   流体包裹体   成矿环境   锡铁山   青海  

摘要： 在分析流体包裹体特征的基础上，提出锡铁山铅锌矿床两种矿石类型成矿流体的特点：条带状矿石具有中低温度（182℃-229℃），低盐度或较低盐度（5．3％-21．9％），密度小于1×10^3kg／m^3，弱酸、弱还原环境；块状矿石具有中高温（224．5℃-341℃）,较高盐度（22．8％-34．7％），密度大于1×10^3kg／m^3，中性、弱还原环境。两种不同类型的矿石也说明了该矿床具有两个不同成矿期次的热液：火山喷流沉积成矿热液在裂谷凹陷盆地富集形成务带状矿石；火山作用期后热液叠加改造前者形成块状矿石。两个不同成矿期次的热液造成锡铁山矿床的矿体和矿石的多样性。

关键词： 微机电系统   微流体系统   微流体驱动  

摘要： 微流体驱动大致可以分为两类:一类是从宏观流体驱动移植过来的驱动方式;另一类是根据微尺度下流体特性设计的驱动方式。对两类不同的驱动方式进行了介绍与比较,前者原理成熟,基本都符合经典流体理论,在亚微米以上级微流体流道尺寸中的应用较广;相比之下,后者设计原理新颖,常用于微米甚至纳米级的微流体系统中,具有更好的发展前景。

摘要： This dissertation reports on the development of devices and concepts for electrical and microfluidic cell manipulation. In the present con- text, the term cell manipulation stands for both cell handling and cell modification. The combination of microfluidic channels with micropatterned elec- trodes allows for the definition of highly localised chemical and elec- trical environments with spatial resolution comparable to the size of a cell. The devices fabricated in the frame of this thesis employ dielec- trophoretic particle handling schemes such as deflection and trapping in pressure-controlled laminar flows to bring cells to - or immobilise them at - locations where cell altering electric fields or chemicals are present. The two concepts of dielectrophoretic cell dipping and cell immersion are introduced and experimentally shown for erythrocytes dipped into Rhodamine in flow, and for individually immobilised Jurkat cells im- mersed by Trypan Blue. Also, in-situ membrane breakdown in high intensity AC electric fields is optically assessed by efflux of haemoglobin (haemolysis) and by in- flux of nucleic stains or fluorescence-enhancing ions. The most advanced experiments are on-chip medium exchange followed immediately by electropermeablisation or electrodeformation. The majority of assays presented in this thesis are carried out in micro- fabricated glass-polymer-glass chips featuring top-bottom electrodes. The devices are fluidically controlled by external gas pressure bridging circuits. Experimental evidence of the unmatched precision of pressure bridg- ing is given in the case of micrometric xy positioning of cells at the intersection of two perpendicular microfluidic channels. Further shown in this document are two methods of optical in-situ temperature measurements, important for bioinstrument characterisa- tion. The two concepts of thermoquenching of a fluorescent dye and the original thermoprecipitation of "smart polymers" are used. The last part of this work

关键词： alfalfa   crop nutrient   trace elements   flue gas desulfurization   petroleum coke   environmental quality   nickel   vanadium  

摘要： To reduce S emissions, petroleum coke with a high concentration of S was combusted with limestone in a circulating fluidized bed (CFB) boiler. The combustion process creates a bed product that has potential for agricultural uses. This CFB product is often alkaline and enriched in S and other essential plant nutrients, but also contains high concentrations of Ni and V. Agricultural land application of CFB product is encouraged, but little information is available related to plant responses and environmental impacts. CFB product and agricultural lime (ag-lime) were applied at rates of 0, 0.5, 1.0, and 2.0 times the soil's lime requirement (LR) to an acidic soil (Wooster silt loam). The 2.0 x LR application rate of CFB product was equivalent to 67.2 Mg ha(-1). Alfalfa yield was increased 4.6 times by CFB product and 3.8 times by ag-lime compared to untreated control. Application of CFB product increased the concentration of V in soil and alfalfa tissue, but not in soil water, and increased the concentration of Ni in soil and soil water, but not in alfalfa tissue. However, these concentrations did not reach levels that might cause environmental problems.

摘要： The goal of this thesis has been to evaluate microfluidic systems for applications in drug delivery. In particular, we have focused on safety in reciprocating pumps, for continuous insulin delivery, and identified the microvalves, as being critical components. We have investigated a technology for engineering of microfluidic components which promises good sealing properties. A good sealing property is a mean to ensure a high safety level for applications in drug delivery, and we have used the technology to fabricate a turning microvalve, which provides a significantly higher safety level compared to deliv- ery systems using prestressed check valves. The technology is based on construction with soft incompressible rubber materials and hard surfaces. By basic studies on sliding friction between rubber and a hard sub- strate we show that friction force scales with contact area, and depends linearly on the contact pressure. Therefore, energy savings are obtained by down-scaling. Similar basic flow studies show that sealing properties depend on contact pressure, and how well the rubber-incompressibility is utilized in the actual geometry. In addition to the basic studies, scaling properties and dependency on contact pressure for turning valves are illustrated by construction and test of a large and a small turning valve. Therefore, low-energy, turning microvalves with high-pressure seals are feasible. The major benefits of down-scaling mechanical systems are the more compact and less energy consuming devices. We show the feasibility of a low-energy, turning microvalve with a high pressure seal by construction and test of a demonstrator with a rod diameter of 250 μm, the actuation energy of opening and closing is 0.15 mJ, and it withstand a pressure above 0.7 MPa. We have also used the studied technology to suggest the design and construction of a pump in an unexplored branch of micropumps, namely, the reciprocating piston pump. The pump utilizes turning microvalves to re

关键词： 微流体系统   乳化液滴   两相流   表面张力  

摘要： 在乳化液的生产中，既要保证离散液滴的快速生成率，又要保证乳化液中的液滴尺度的均匀一致。目前最合适的制备乳化液滴的方法是采用微流体系统法，本课题以液滴动力学和微流体系统为基础，分析不同工况下各物理参数对乳化液滴尺寸和生成频率的影响，对微管道中乳化液离散液滴的生成进行研究。鉴于以往微管道中液滴的研究主要采用的实验方法，本文运用Fluent软件，模拟两种形式的微管道中乳化液滴的生成过程。\n 本文完成了T型微管乳化液滴的数值模拟计算，经过体积分数的图谱分析，与文献实验中的结果符合的较好，说明文中建立的模型模拟计算微管中的乳化液的形成过程，是可行的。在此基础上，模拟了CF型微管中乳化液滴的形成过程，并针对常规工况下液滴形成的规律进行分析，得出以下结论：其他参数一定时，随着连续相的速度Vc增大，液滴的半径减小，生成时间减少；随着分散相速度Vd增大，液滴的半径增大，生成时间也减少。随着表面张力的增加，液滴的半径增大，液滴的生成的时间也越长。水包油型和油包水型液滴的对比分析可得：在同一模型和工况下，水包油型液滴的三维尺寸明显比油包水液滴的三维尺寸大，生成液滴的时间也相对于油包水液滴要长一些。最后本文初步预测了在特殊工况下CF型乳化液滴中各物理参数对液滴频率和半径的影响。得出的结论与常规情况下基本一致。

摘要： Rimstone dams are barriers composed mainly of calcium carbonate deposited from solution in ground and surface waters. These structures form a subclass of travertine formations which include owstone and stalactites, and often appear in close proxim- ity to these features. The initial formation of rimstone dams requires some degree of cave slope, a semi-continuous ow of water, and the preexistence of irregularities in the cave oor. These dams develop at heights from a few millimeters to several me- ters within free-surface streams, and create a self-propagating dam and pool structure which grows upward. The genesis and evolution of rimstone dams is theorized to be the result of hydrodynamic and chemical-kinetic control. The purpose of this paper is to develop a model, the scope of which encompasses both hydrodynamics and the reactive transport, which is qualitatively consistent with observed and experimentally derived results, and method for analyzing the mechanism governing the formation of these unique rimstone features.

关键词： 雷诺数   鞭毛   动力蛋白   渗透压  

摘要： 在流体环境中生存的生物,会形成适应特定环境的外形结构、内部组织、运动模式以及自身物质运行的方式。通过具体例子从宏观和微观生物结构分析了这些特点。在试验分析中加入了定量分析的方法,能够更准确地描述,也能更清楚地看到隐藏在生物内部的这些规律。