Development of a Pico-joule Calorimeter Instrument

微机械加工技术的进步和高精度电子器件的出现产生了一类新的热传感仪器。 这些进展将对开发一种新的超灵敏量热仪产生重大影响，该仪器用于测量超过纳焦耳到皮焦耳灵敏度的能量。 该奖项提供了支持，以开发一个量热计，这将具有皮焦耳灵敏度，通过使用新的微加工技术。 这台仪器将用于物质系统的基本能量测量，范围从仅含100个原子的团簇之间的相互作用到纳升生物样品的真实的时间测量。量热法是研究物质基本性质的理想工具，例如熔点、熔化热和热容。 然而，直到最近，量热法仅限于研究散装材料。 现在，新的进展为我们提供了第一次机会，将这种强大的技术应用于纳米尺度的材料，在尺寸上，材料的性质与其体积值相差很大。 Bertsch最近在《科学》杂志上发表了一篇题为“团簇中的增强熔化”的文章，强调了量热法中的新突破技术。 他讨论了光束[2]和表面[3]上自由团簇熔化温度降低的尺寸依赖现象。使用新技术，拟议中的仪器将在灵敏度方面产生10，000倍的量子飞跃，超过任何现有的传统系统。 这种灵敏度的提高将允许在新的热力学测量水平上探索材料特性。皮热量计将被应用于广泛的材料合作研究，包括（i）增强熔点研究，（ii）薄膜生长过程中表面团簇成核、聚结和生长的直接热力学研究，（iii）热退火过程中离子注入损伤的缺陷恢复，（iv）液晶（LC）氟化嵌段聚合物的表面重建，以及（v）单细胞胚胎中细胞分裂的研究。来自伊利诺伊大学、芝加哥和康奈尔大学的教师和学生将参与这一新仪器的开发。%**

9803019AllenAdvances in techniques of micro-machining small microheater elements and the availability of high precision electronics have generated a new class of heat sensing instruments. These advances will have major impact in developing a new ultra-sensitive calorimetry instrument for measuring energy beyond nanojoule to picojoule sensitivities. This award provides support to develop a calorimeter which will have picojoule sensitivity by using novel micro-machining techniques. This instrument will be used for fundamental energy measurements in material systems ranging from interactions between clusters containing only a hundred atoms to the real time measurement of nanoliter biological samples.Calorimetry is the ideal tool for studying the fundamental properties of material, e.g. the melting point, heat of fusion, and the heat capacity. However, until recently calorimetry was limited to studies of bulk material. Now, new advances have provided us with the first opportunity to apply this powerful technique on the nanometer scale of material, at dimensions where material properties deviate tremendously from their bulk values. A recent article in SCIENCE by Bertsch [1] entitled " Enhanced Melting in Clusters," highlights the new breakthrough techniques in calorimetry. He discusses the size-dependent phenomenon of reduced melting temperature of free clusters in a beam [2] and on a surface [3].Using the new technology, the proposed instrument will generate a quantum leap in sensitivity of factor of 10,000 over any current conventional systems. This increased sensitivity will allow exploration of material characterization at a new level of thermodynamic measurement.The picocalorimeter will be applied to a broad range of collaborative materials studies including (i) enhanced melting point studies, (ii) direct thermodynamic studies of nucleation, coalescence and growth of surface clusters during film growth, (iii) defect recovery of ion-implant damage during thermal annealing, (iv) surface reconstruction of Liquid Crystal (LC) fluorinated block polymers, and (v) studies of cell division in a single-cell embryo.Faculty and students from the University of Illinois, University of Chicago, and Cornell University will be involved with the development of this new instrument.%%%***