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101.
The question of pattern in architecture generally divides architects into two distinct groups: those with an aesthetic interest in man-made ornament; and those who take a deeper interest in the processes that underlie the formation of pattern in the natural world. An investigation of the performative, though, enables an exploration of pattern that arises out of the interaction of man-made interventions with the natural environment. Michael Hensel , Professor for research by Design at AHO, the Oslo School of Architecture and Design, and Achim Menges of the Emtech (Emergent Technologies and Design programme) at the Architectural Association in London, explore this arena based on their research and educational work at the AA and other international institutions, which focuses on aspects of performance in the built environment. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
102.
DeCarlo PF Kimmel JR Trimborn A Northway MJ Jayne JT Aiken AC Gonin M Fuhrer K Horvath T Docherty KS Worsnop DR Jimenez JL 《Analytical chemistry》2006,78(24):8281-8289
The development of a new high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) is reported. The high-resolution capabilities of this instrument allow the direct separation of most ions from inorganic and organic species at the same nominal m/z, the quantification of several types of organic fragments (CxHy, CxHyOz, CxHyNp, CxHyOzNp), and the direct identification of organic nitrogen and organosulfur content. This real-time instrument is field-deployable, and its high time resolution (0.5 Hz has been demonstrated) makes it well-suited for studies in which time resolution is critical, such as aircraft studies. The instrument has two ion optical modes: a single-reflection configuration offers higher sensitivity and lower resolving power (up to approximately 2100 at m/z 200), and a two-reflectron configuration yields higher resolving power (up to approximately 4300 at m/z 200) with lower sensitivity. The instrument also allows the determination of the size distributions of all ions. One-minute detection limits for submicrometer aerosol are <0.04 microg m(-3) for all species in the high-sensitivity mode and <0.4 microg m(-3) in the high-resolution mode. Examples of ambient aerosol data are presented from the SOAR-1 study in Riverside, CA, in which the spectra of ambient organic species are dominated by CxHy and CxHyOz fragments, and different organic and inorganic fragments at the same nominal m/z show different size distributions. Data are also presented from the MIRAGE C-130 aircraft study near Mexico City, showing high correlation with independent measurements of surrogate aerosol mass concentration. 相似文献
103.
We report on chemically specific, subsurface imaging with high spatial resolution. Using tip-enhanced Raman spectroscopy, we probe carbon nanotubes buried beneath a host dielectric media. We demonstrate our ability to map and resolve specific vibrational modes with 30 nm spatial resolution for dielectric layers with different thicknesses. 相似文献
104.
Klaus Pollinger Robert Hennig Miriam Breunig Joerg Tessmar Andreas Ohlmann Ernst R. Tamm Ralph Witzgall Achim Goepferich 《Small (Weinheim an der Bergstrasse, Germany)》2012,8(21):3368-3375
Renal nanoparticle passage opens the door for targeting new cells like podocytes, which constitute the exterior part of the renal filter. When cyclo(RGDfC)‐modified Qdots are tested on isolated primary podocytes for selective binding to the αvβ3 integrin receptor a highly cell‐ and receptor‐specific binding can be observed. In displacement experiments with free cyclo(RGDfC) IC50 values of 150 nM for αvβ3 integrin over‐expressing U87‐MG cells and 60 nM for podocytes are measured. Confocal microscopy shows a cellular Qdot uptake into vesicle‐like structures. Our ex vivo study gives clear evidence that, after renal filtration, nanoparticles can be targeted to podocyte integrin receptors in the future. This could be a highly promising approach for future therapy and diagnostics of podocyte‐associated diseases. 相似文献
105.
Völk S Knall F Schülein FJ Truong TA Kim H Petroff PM Wixforth A Krenner HJ 《Nanotechnology》2012,23(28):285201
Acousto-electric charge conveyance induced by a surface acoustic wave (SAW) is employed to dissociate photogenerated excitons. Over macroscopic distances, both electrons and holes are injected sequentially into a remotely positioned, isolated and high quality quantum emitter, a self-assembled quantum post. This process is found to be highly efficient and to exhibit improved stability at high acoustic powers when compared to direct optical pumping at the position of the quantum post. These characteristics are attributed to the wide matrix quantum well in which charge conveyance occurs and to the larger number of carriers available for injection in the remote configuration, respectively. The emission of such pumped quantum posts is dominated by recombination of neutral excitons and fully directional when the propagation direction of the SAW and the position of the quantum post are reversed. 相似文献
106.
Cornelius Demuth Matthias BiedaAndrés F. Lasagni Achim MahrleAndreas Wetzig Eckhard Beyer 《Journal of Materials Processing Technology》2012,212(3):689-699
This work presents a new approach to the thermal modelling of direct laser interference patterning (DLIP). The spatial and temporal evolution of the temperature distribution within metallic substrates, which are irradiated by nanosecond pulses during the DLIP process, is computed by means of a smoothed particle hydrodynamics (SPH) method. The developed model considers the conversion of laser energy into heat within a very thin surface layer, heat conduction into the bulk material and the effect of latent heat during involved phase transformations. The importance of proper determination of characteristic SPH parameters and adequate spatial resolution of the computational domain on the accuracy of the numerical solution is discussed in detail. The computed temperature distributions are in good agreement with the results of a previously developed FEM model and correspond very well to simultaneously performed experimental investigations. 相似文献
107.
Moritz Fleischmann Jan Knippers Julian Lienhard Achim Menges Simon Schleicher 《Architectural Design》2012,82(2):44-51
Material behaviour computes form. In the physical world, material form is always inseparably connected to internal constraints and external forces; in the virtual space of digital design, though, form and force are usually treated as separate entities – divided into processes of geometric form generation and subsequent engineering simulation. Using the example of the interdisciplinary ICD/ITKE Research Pavilion, constructed at the University of Stuttgart in 2010, Moritz Fleischmann, Jan Knippers, Julian Lienhard, Achim Menges and Simon Schleicher explain how feedback between computational design, advanced simulation and robotic fabrication expands the design space towards previously unexplored architectural possibilities. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
108.
109.
Amstad Fabienne T.; Meier Laurenz L.; Fasel Ursula; Elfering Achim; Semmer Norbert K. 《Canadian Metallurgical Quarterly》2011,16(2):151
A literature review of studies analyzing work–family conflict and its consequences was conducted, and 427 effect sizes were analyzed meta-analytically. Work–family conflict was analyzed bidirectionally in terms of work interference with family (WIF) and family interference with work (FIW). We assessed 3 categories of potential outcomes: work-related outcomes, family-related outcomes, and domain-unspecific outcomes. Results show that WIF and FIW are consistently related to all 3 types of outcomes. Both types of interrole conflict showed stronger relationships to same-domain outcomes than to cross-domain outcomes. Thus, WIF was more strongly associated with work-related than with family-related outcomes, and FIW was more strongly associated with family-related than with work-related outcomes. In moderator analyses, parenthood could not explain variability in effect sizes. However, time spent at work did moderate the relationships between WIF and family-related outcomes, as well as FIW and domain-unspecific outcomes. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
110.
Achim Jungbluth Michael Kolloch F. Marx Konrad Pfeilsticker 《European Food Research and Technology》1997,204(3):215-220
The initial steps of the degradation of L-de- hydroascorbic acid (L-DHA) in acidic aqueous solutions and the catalytic effect of different transition metal ions on this reaction were studied. The main product was identified as 3,6-furanosido-2,3-hexodiulosonic acid-2-hydrate (compound I) by GLC-MS and 13C-NMR, formed by lactone hydrolysis and hydration of the carbonyl group in the C-2 position of L-dehydroascorbic acid. In addition, number of other compounds were detected; they are formed from compound I by simple enolisation, lactonisation, hydration and dehydration reactions as well as by cleavage and formation of cyclic half acetal bonds. The chemical structures of these compounds were tentatively deduced by the mass spectra of their TMS derivatives and a reaction scheme for their formation is proposed. The velocity and the direction of the reactions were found to be strongly influenced by the presence of catalytic amounts of different transition metal ions. It was concluded that in acidic medium, in contrast to the situation in neutral and alkaline solutions, the opening of the lactone ring of L-DHA is, to a certain degree, a reversible reaction. 相似文献