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Journal of Statistical Physics - We show that macro-molecular self-assembly can recognize and classify high-dimensional patterns in the concentrations of N distinct molecular species. Similar to... 相似文献
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Yosyp Schwab Harkirat S. Mann Brian N. Lang Jarrett L. Lancaster Ronald J. Parise Anita J. Vincent‐Johnson Giovanna Scarel 《Complexity》2014,19(4):44-55
The mechanism that activates a bi‐junction power generator under the effects of heat is the Seebeck effect, that is, the production of voltage difference ΔV(t) is directly proportional to the temperature difference ΔT(t) between the “hot” and “cold” junctions of the device. This phenomenon is well established and is known as thermoelectric power generation. Here, it is shown that, instead, the causal and linear relationship between ΔV(t) and ΔT(t) is lost when continuous broadband infrared (CB‐IR) radiation illuminates a bi‐junction power generator in an insulated compartment. The observed phenomenon is IR power generation. Heat transfer calculations fail in explaining the experimental trends. The interaction between CB‐IR radiation and the charge carriers in the bi‐junction power generator might play a role in the ΔV(t) production, depending upon the geometry of the experimental setup. The longitudinal propagation of collective oscillations, for example, polaritons, in the plates protecting the “hot” and “cold” junctions of the bi‐junction power generator could explain the ΔV(t) production and the characteristic time constants. The findings should be considered in the design, fabrication, and improvement of thermopiles, power meters, and IR energy‐harvesting devices. © 2013 Wiley Periodicals, Inc. Complexity 19: 44–55, 2014 相似文献
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In d dimensions, first-order tensor-product finite-element (FE) approximations of the solutions of second-order elliptic problems are well known to converge algebraically, with rate at most 1/d in the energy norm and with respect to the number of degrees of freedom. On the other hand, FE methods of higher regularity may achieve exponential convergence, e.g. global spectral methods for analytic solutions and hp methods for solutions from certain countably normed spaces, which may exhibit singularities. In this note, we revisit, in one dimension, the tensor-structured approach to the h-FE approximation of singular functions. We outline a proof of the exponential convergence of such approximations represented in the quantized-tensor-train (QTT) format. Compared to special approximation techniques, such as hp, that approach is fully adaptive in the sense that it finds suitable approximation spaces algorithmically. The convergence is measured with respect to the number of parameters used to represent the solution, which is not the dimension of the first-order FE space, but depends only polylogarithmically on that. We demonstrate the convergence numerically for a simple model problem and find the rate to be approximately the same as for hp approximations. (© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Mirjam C. K. Geditz Georg Heinkele Asma Ahmed Peter G. Kremsner Reinhold Kerb Matthias Schwab Ute Hofmann 《Analytical and bioanalytical chemistry》2014,406(17):4299-4308
Artesunate (AS), a hemisuccinate derivative of artemisinin, is readily soluble in water and can easily be used in formulations for parenteral treatment of severe malaria. AS is rapidly hydrolyzed to the active metabolite dihydroartemisinin (DHA) and primarily eliminated by biliary excretion after glucuronidation. To investigate systematically the AS metabolism and pharmacokinetics, a novel liquid chromatography–tandem mass spectrometry (LC-MS/MS) method for the simultaneous quantification of AS and its metabolites DHA and DHA glucuronide (DHAG) in human plasma samples was developed. Compared to previous methods, our method includes for the first time the quantification of the glucuronide metabolite using a newly synthesized stable isotope-labeled analogue as internal standard. Sample preparation was performed with only 50 μL plasma by high-throughput solid-phase extraction in the 96-well plate format. Separation of the analytes was achieved on a Poroshell 120 EC-C18 column (50*2.1 mm, 2.7 μm, Agilent Technologies, Waldbronn, Germany). The method was validated according to FDA guidelines. Calibration curves were linear over the entire range from 1 to 2,500 nM (0.4–961.1 ng/mL), 165 to 16,500 nM (46.9–4,691.8 ng/mL), and 4 to 10,000 nM (1.8–4,604.7 ng/mL) for AS, DHA, and DHAG, respectively. Intra- and interbatch accuracy, determined as a deviation between nominal and measured values, ranged from ?5.7 to 3.5 % and from 2.7 to 5.8 %, respectively. The assay variability ranged from 1.5 to 10.9 % for intra- and interbatch approaches. All analytes showed extraction recoveries above 85 %. The method was successfully applied to plasma samples from patients under AS treatment. Figure
Chemical structures and combined MRM chromatograms of the analytes AS, DHA and DHAG 相似文献
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W. Morawek D. Ackermann T. Brohm H. -G. Clerc U. Gollerthan E. Hanelt M. Horz W. Schwab B. Voss K. -H. Schmidt F. P. Heßberger 《Zeitschrift für Physik A Hadrons and Nuclei》1991,341(1):75-78
The fusion of the massive systems110Pd+104Ru and110Pd+110Pd was uniquely identified by observing the a decay of the evaporation residues. The observed distribution of the fusion cross section on the different evaporation-residue channels is in clear contradiction to calculations based on the compound-nucleus model. As a possible explanation the precompound evaporation of a particles is proposed. 相似文献
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A high intensity variable energy positron beam has been constructed at Brookhaven National Laboratory (BNL). Positrons from
a 97 mCi22Na source are moderated by a thin layer of solid neon. A magnetic guiding system delivered up to 5×106 e+/sec to an experiment. Currently, tests are under way to facilitate the operation with the magnetic guiding system or—for
other experimental sites—with an electrostatic beam transport. The electrostatic lenses are fabricated from μ-metal. No compensation
of the earth's magnetic field is required. Several experiments can utilize the beam on a time-sharing basis. In the near future,
the source will be replaced by64Cu, which has a much higher activity. Beam intensities up to 109 e+/sec are expected. 相似文献
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