Low-firing thick-film piezoresistive sensors for medical instruments

In this work, a low-firing thick-film materials system allowing fabrication of piezoresistive sensors on surgical alloys is presented in detail, with application to a force-sensing surgical instrument. The system comprises a series of individual thick-film dielectric, conductor, resistive and overglaze compositions based on a lead borosilicate glass matrix. The moderate achieved firing temperature, around 625 °C, greatly increases compatibility with metallic substrates, allowing the use of high-strength medical alloys with low thermal degradation. Specific fillers for the dielectric layers increase adhesion on steel substrates and allow thermal matching to austenitic and ferritic/martensitic steels, as well as titanium alloys, and preliminary work demonstrating reactive stabilisation of the dielectric layer to achieve an even wider process window is also shown. Finally, the functionality of this materials system is successfully demonstrated here by implementing it into a previously developed ligament-balancing force sensor for total knee arthroplasty (TKA) [1].     

The origins of town planning in New Zealand 1900–1926: a divergent path?

This article explores the origins of the development of town planning in New Zealand. In doing so it attempts to commence the task of charting the planning history of that country, a task that to date has been only partly or incompletely addressed. The discussion is set within a comparative framework that tries to relate the development and establishment of town planning in New Zealand to the factors that encouraged its development in Britain, the United States and Australia. From this exploration there emerges a picture of town planning developing in New Zealand not as much in response to the existence of slums and public health concerns, but as a product of the interests of some key individuals and their desire to ensure that the problems of the Old World were not perpetuated in New Zealand. Thus the diffusion of ideas on town planning from overseas becomes an important motivation to establishing town planning in New Zealand. Equally the need for local body reform and the willingness of the central state to intervene helped to ensure that town planning was accepted as an appropriate tool to regulate the urban fabric.     

Occurrence of sotolon,abhexon and theaspirane‐derived molecules in Gueuze beers. Chemical similarities with ‘yellow wines’

The typical Belgian Gueuze beers are produced with aged hop from a grist of malt and wheat, according to a very long oxidation process (extended boiling, cooling overnight in an open‐air container, oak‐barrel ageing). Two theaspirane‐oxidation‐derived products, dihydrodehydro‐β‐ionone and 4‐hydroxy‐7,8‐dihydro‐β‐ionone, are evidenced here for the first time in Gueuze beers. Both compounds have been recently identified in oxidative wines such as Jura Flor‐Sherry and Sauternes wines. Another analogy with Jura Flor‐Sherry wines was the presence of the nutty/curry odorants sotolon and abhexon, although at lower concentrations. Copyright © 2012 The Institute of Brewing & Distilling     

Development of a qualitative test method for the cleanability of polymer woven filter media

In this paper a new method for cleaning of filter media is presented, and the cleanability with different textures and surface finishes is compared. With the method described, it is possible to evaluate the quality of the cleaning process. According to the German VDMA standard cleaning test, riboflavin and malt extract are applied as model contaminants for evaluation of the cleaning results. To compare the cleanability of filter media with different properties and geometries the results are adapted to the law of mass transfer and to the Sherwood number, a dimensionless parameter describing the quality of a cleaning process.     

设计资本

UN设计六步法(或多或少) 现如今,建筑学科敞开大门接受彻底变革的可能性.那些关于收益和增长的叙述曾在过去几十年中,阐释并大力推进建筑学的发展,并为其提供了合理的依据;如今这些叙述已被打断.现在的焦点在于,如何对建筑核心领域内的一切可能的重要因素提炼阐明新的概念.一切事,是的,所有一切事都可以进行改变,整个世界需要共同面临的问题和需求如此之大. 意识到这一挑战还需要了解其有益的潜力;新颖引领建筑学蓬勃发展.如果缺乏连续的物质、文化和意识上的创新,行业便失去其特殊性,而成为建筑行业中平淡无奇的一部分.通过UNStudio,我们早就意识到了这一点,这就是为什么我们在许多不同的方向上推动自己,不断应对新的挑战和问题.但与此同时,这一实验态度也使我们有意识地致力于尽可能多的建造.在全球化经济的背景下,脱离建筑行业的危险性从来就不是我们的首选方案.     

Influence of Si:Al ratio on the microstructural and mechanical properties of a fine-limestone aggregate alkali-activated slag concrete

Three series of fine limestone aggregate, alkali-activated blast furnace slag (AAS) concretes were fabricated and tested; two through activation with waterglass/NaOH solution, of which one included NaCl as a retarding agent, and one activated by Na₂CO₃. Each of these series was made up of three formulae containing different amounts of Al₂O₃. The compressive strengths of the series activated by waterglass/NaOH after 28 days were ≈65 ± 5.3 MPa, a 22% increase compared to previously reported formulae containing no additional Al₂O₃. Increasing the amount of Al₂O₃ did not further increase strength, however. The Na₂CO₃-activated formulae had strengths of ≈35 ± 3 MPa after 28 days, representing no increase in strength over formulae not containing Al₂O₃ previously reported. X-ray diffraction showed the main binding phase to be calcium silicate hydrate (C–S–H) gel, as is commonly found in ordinary Portland cement (OPC). Fourier transform infrared spectroscopy showed little difference from the previously reported results for formulae not containing Al₂O₃ and strongly resemble the spectra reported elsewhere for C–S–H. Electron microscopy, coupled with energy dispersive spectroscopy, showed the cementing phase to be a single homogenous phase—not a mixed system of geopolymer and C–S–H gel—with a lower volume fraction of unreacted slag than formulae without Al₂O₃. The reason for the increase in strength of Al₂O₃-containing formulae is unclear, but is unlikely to be ascribed to the formation of large amounts of ‘geopolymers’ and may be related to a possible increase in reaction temperature of between 2 and 5°C, depending on amount of additive.