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51.
Kegler K Konieczny M Dominguez-Espinosa G Gutsche C Salomo M Kremer F Likos CN 《Physical review letters》2008,100(11):118302
Optical tweezers are employed to measure the forces of interaction within a single pair of DNA-grafted colloids, dependent on the molecular weight of the DNA chains, and the concentration and valence of the surrounding ionic medium. The resulting forces are short range and set in as the surface-to-surface distance between the colloidal cores reaches the value of the brush height. The measured force-distance relation is analyzed by means of a theoretical treatment that quantitatively describes the effects of compression of the chains on the surface of the opposite-lying colloid. Quantitative agreement with the experiment is obtained for all parameter combinations. 相似文献
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53.
Dr. Stefan Giselbrecht Dr. Bastian E. Rapp Prof. Dr. Christof M. Niemeyer 《Angewandte Chemie (International ed. in English)》2013,52(52):13942-13957
The term “cyborg” refers to a cybernetic organism, which characterizes the chimera of a living organism and a machine. Owing to the widespread application of intracorporeal medical devices, cyborgs are no longer exclusively a subject of science fiction novels, but technically they already exist in our society. In this review, we briefly summarize the development of modern prosthetics and the evolution of brain–machine interfaces, and discuss the latest technical developments of implantable devices, in particular, biocompatible integrated electronics and microfluidics used for communication and control of living organisms. Recent examples of animal cyborgs and their relevance to fundamental and applied biomedical research and bioethics in this novel and exciting field at the crossroads of chemistry, biomedicine, and the engineering sciences are presented. 相似文献
54.
Fischer RF Baltes C Weiss K Pazhenkottil A Rudin M Boesiger P Kozerke S 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2011,211(1):80-88
In this work Linear Response Equilibrium (LRE) and Echo-planar spectroscopic imaging (EPSI) are compared in terms of sensitivity per unit time and power deposition. In addition an extended dual repetition time scheme to generate broad stopbands for improved inherent water suppression in LRE is presented. The feasibility of LRE and EPSI for assessing cholesterol esters in human carotid plaques with high spatial resolution of 1.95×1.15×1.15 mm(3) on a clinical 3T MR system is demonstrated. In simulations and phantom experiments it is shown that LRE has comparable but lower sensitivity per unit time relative to EPSI despite stronger signal generated. This relates to the lower sampling efficiency in LRE relative to EPSI as a result of limited gradient performance on clinical MR systems. At the same time, power deposition of LRE is significantly reduced compared to EPSI making it an interesting niche application for in vivo high field spectroscopic imaging of metabolites within a limited bandwidth. 相似文献
55.
Jing Wang Christof Asbach Heinz Fissan Tim Hülser Thomas A. J. Kuhlbusch Drew Thompson David Y. H. Pui 《Journal of nanoparticle research》2011,13(4):1373-1387
Nanotechnology has great potential to transform science and industry in the fields of energy, material, environment, and medicine.
At the same time, more concerns are being raised about the occupational health and safety of nanomaterials in the workplace
and the implications of nanotechnology on the environment and living systems. Studies on environmental, health, and safety
(EHS) issues of nanomaterials have a strong influence on public acceptance of nanotechnology and, eventually, affect its sustainability.
Oversight and regulation by government agencies and non-governmental organizations (NGOs) play significant roles in ensuring
responsible and environmentally friendly development of nanotechnology. The EHS studies of nanomaterials can provide data
and information to help the development of regulations and guidelines. We present research results on three aspects of EHS
studies: physico-chemical characterization and measurement of nanomaterials; emission, exposure, and toxicity of nanomaterials;
and control and abatement of nanomaterial releases using filtration technology. Measurement of nanoparticle agglomerates using
a newly developed instrument, the Universal NanoParticle Analyzer (UNPA), is discussed. Exposure measurement results for silicon
nanoparticles in a pilot scale production plant are presented, as well as exposure measurement and toxicity study of carbon
nanotubes (CNTs). Filtration studies of nanoparticle agglomerates are also presented as an example of emission control methods. 相似文献
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Wahl Pierre Ly-Gagnon Dany-Sebastien Debaes Christof Miller David A. B. Thienpont Hugo 《Optical and Quantum Electronics》2012,44(3-5):285-290
Numerical calculations with finite-difference time-domain (FDTD) on metallic nanostructures in a broad optical spectrum require an accurate approximation of the permittivity of dispersive materials. In this paper, we present the algorithms behind B-CALM (Belgium-California Light Machine), an open-source 3D-FDTD solver operating on Graphical Processing Units with multi-pole dispersion models. Our modified architecture shows a reduction in computing times for multi-pole dispersion models. We benchmark B-CALM by computing the absorption efficiency of a metallic nanosphere on a broad spectral range with a six-poles Drude-Lorentz model and compare it with Mie theory.
相似文献58.
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Pons M Ahufinger V Wunderlich C Sanpera A Braungardt S Sen De A Sen U Lewenstein M 《Physical review letters》2007,98(2):023003
We demonstrate the possibility of realizing a neural network in a chain of trapped ions with induced long range interactions. Such models permit one to store information distributed over the whole system. The storage capacity of such a network, which depends on the phonon spectrum of the system, can be controlled by changing the external trapping potential. We analyze the implementation of error resistant universal quantum information processing in such systems. 相似文献