纳米科学和技术的二次浪潮

在过去的十年里纳米科学的首次浪潮澎湃而过。在此期间，国际、国内以及香港的学者已向世人证实他们可以采用“build-up”或“build-down”的办法制造大量的纳米管，纳米线以及纳米团簇，这些努力已经表明，如果纳米结构能够低廉地制造，那我们就会有更丰硕的收获。尺度小于20纳米的结构会展现非经典的性质，这提供给我们一个用全新的想法来制造功能器件的基础。在半导体工业，制造结构尺寸小于70纳米器件的能力允许器件的持续微型化。在下一个10年中，纳米科学和技术的另一次浪潮将可能来临，在这个新时期，科学家和工程师需要展示人们对纳米结构的期待功能以及证实他们的进一步的潜力，拥有在纳米结构实际器件的尺寸、组份，有序和纯度上的良好控制能力将实现人们期望的功能，在本文中，我们将讨论纳米科学和技术在新时期里发展所面对的困难和挑战。一系列新的方法将被讨论。我们还将讨论倘若这些困难能够被克服我们可能会有的收获。     

高强度聚焦超声(HIFU)的声场检测

针对高强度聚焦超声（HIFU）声场的特点，对高强度聚焦超声（HIFU）声场检测的方法如，辐射压力法、水听器测量法、光纤检测和光学检测进行了综述，并对上述检测方法进行了比较。     

After Boyle and the Leviathan: the Second Generation of British Air Pumps

This paper examines the second generation of British air pumps, covering the period 1700–1750. The air pump originated in the 1650s and 1660s thanks to the work of Otto von Guericke in Magdeburg, Robert Boyle in Oxford and London, and Accademia del Cimento in Florence. While these first models were often seen as unreliable and temperamental, and available to a small group only, the next period saw the air pump transformed into a publicly accessible device for use in public and private demonstrations, in practical applications, as well as in the production of new knowledge. In England, the instrument maker Francis Hauksbee and his followers played a decisive role in this process, which was connected, among other things, to popular medicine, anatomy and health. In this period, pneumatics (the field of air pumps and air-pump practice) reached a state where the pump came to be regarded as an unproblematic tool; and where a ‘vacuum’ came to be thought of and handled as an object.     

中小科技企业在香港创业板上市需特别重视的几个问题

中小科技企业由于自身的一些特点,如创建初期的风险较高、自身的资产规模较小、经营体制不健全、盈利能力差等,加上现阶段我国又缺乏必要的信用担保体系等的限制,使得其获得国有商业银行贷款的可能性不大。在这种情况下,众多中小科技企业寄希望于直接融资这一渠道上。本文试对中小科技企业在香港创业板市场上市筹备中的难点问题进行深入分析,希望有助于更多的科技企业成功上市。     

The reversibility objection against the Second Law of thermodynamics viewed,and avoided,from a logical point of view

In this paper we offer a formal-logical analysis of the famous reversibility objection against the Second Law of thermodynamics. We reconstruct the objection as a deductive argument leading to a contradiction, employing resources of standard quantified modal logic and thereby highlighting explicit and implicit assumptions with respect to possibility, identity, and their interaction. We then describe an alternative framework, case-intensional first order logic, that has greater expressive resources than standard quantified modal logic. We show that in that framework we can account for the role of sortals in possibility judgments. This allows us to formalize the relevant truths involved in the reversibility objection in such a way that no contradiction ensues. We claim that this analysis helps to understand in which way the Second Law is, specifically, a law of thermodynamics, but not of systems of particles in general.