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The sonochemical synthesis of inorganic and biological materials.

机译：声化学合成无机和生物材料。

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Understanding and harnessing the interaction between energy and matter is a basic scientific endeavor. The use of high intensity ultrasound to initiate chemical reactions, as opposed to traditional energy sources such as heat and light, has opened new avenues of research. The mechanism of sonochemistry involves acoustic cavitation: the formation, growth, and collapse of bubbles in a liquid. New biological and inorganic materials can be synthesized using this unusual high energy source.; This thesis is divided into two parts. The first part describes the synthesis, characterization and applications of proteinaceous microspheres. We developed a sonochemical technique to synthesize microspheres filled with water-insoluble whose shell is composed entirely of albumin protein. Scanning electron microscopy, optical microscopy, and particle counting characterization reveals that these microcapsules are spherical with typical concentrations of 1.5 {dollar}times{dollar} 10{dollar}sp9{dollar} microcapsule/mL. The microcapsule synthesized have a narrow Gaussian size distribution (average diameter 2.5 {dollar}pm{dollar} 1.0 {dollar}mu{dollar}m). Microcapsule formation is strongly inhibited by free radical traps, by superoxide dismutase (but not by catalase), by an absence of O{dollar}sb2{dollar}, and by a lack of free cysteine residues in the protein. The microcapsules are held together by disulfide bonds between protein cysteine residues, and superoxide (sonochemically produced during acoustic cavitation) is the oxidizing agent that cross-links the proteins. These biological materials have many medical uses including drug delivery and contrast agents for magnetic resonance imaging and echosonography.; The second part of my thesis develops the use of ultrasound for the synthesis of unusual inorganic materials. Specifically, we have explored the sonochemical synthesis, characterization, and catalytic reactivity of amorphous iron. Enormous heating and cooling rates of between 10{dollar}sp9{dollar} to 10{dollar}sp{lcub}13{rcub}{dollar} K/sec are produced during acoustic cavitation. Ultrasonic irradiation of iron pentacarbonyl, a volatile inorganic compound, produces nearly pure amorphous iron. X-ray powder diffraction and electron microdiffraction, transmission electron microscopy, and differential scanning calorimeter techniques showed the iron powder to be amorphous. The amorphous iron is a reactive catalyst for the Fischer-Tropsch hydrogenation of CO and for cyclohexane hydrogenolysis and dehydrogenation.
机译：了解和利用能量与物质之间的相互作用是一项基本的科学努力。与传统的能源（例如热和光）相反，使用高强度超声来引发化学反应，开辟了新的研究途径。声化学的机理涉及声空化：液体中气泡的形成，生长和破裂。利用这种不同寻常的高能量来源，可以合成新的生物和无机材料。本文分为两个部分。第一部分描述了蛋白质微球的合成，表征和应用。我们开发了一种声化学技术来合成充满水不溶性物质的微球，其壳层完全由白蛋白组成。扫描电子显微镜，光学显微镜和颗粒计数表征表明，这些微囊是球形的，典型浓度为1.5 {dol}×{dol} 10 {dol} sp9 {dol} / mL。合成的微胶囊具有狭窄的高斯尺寸分布（平均直径为2.5 {pm} pm {dol} 1.0 {dol} mu {dol} m）。微胶囊的形成受到自由基陷阱，超氧化物歧化酶（但不受过氧化氢酶的抑制），缺少Osbsb2 {dollar}以及蛋白质中游离半胱氨酸残基的强烈抑制。微囊通过蛋白质半胱氨酸残基之间的二硫键结合在一起，而超氧化物（在声空化过程中以声化学方式产生）是使蛋白质交联的氧化剂。这些生物材料具有许多医学用途，包括用于磁共振成像和超声检查的药物输送和造影剂。我的论文的第二部分发展了超声波在特殊无机材料合成中的应用。具体来说，我们探索了非晶铁的声化学合成，表征和催化反应性。在声空化过程中，产生的加热和冷却速率极大地介于10 {dol}} 9 {dol}至10 {dol}} {lcub} 13 {rcub} {dol} K / sec之间。五羰基铁（一种挥发性的无机化合物）的超声波辐照产生几乎纯的非晶铁。 X射线粉末衍射和电子微衍射，透射电子显微镜和差示扫描量热技术显示铁粉为非晶态。非晶铁是用于CO的费-托加氢以及环己烷加氢和脱氢的反应性催化剂。

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