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21.
This is the second part of a paper, which is concerned with the development of a numerical algorithm for the solution of a class of differential games. The theoretical derivation is made in Part I and this part exemplifies the use of the algorithm on an atmospheric pursuit-evasion game with a nonlinear dynamic structure. The applicability and efficiency of the method is discussed in a concluding section. 相似文献
22.
The emission of volatile organic compounds (VOC) from nine toner powders and eleven types of processed paper from photocopying machines (6), laser (3) and matrix printers (21, and one carbonless copy fm has been measured. A total of 61 VOC from toner powders were identified by heating (185 °C) the powder for three minutes for thermal desorption and by gas chromatography followed by the use of low and high resolution EI and CI mass spectrometry. VOC from processed paper were analyzed by headspace sampling on Tenax TA from nylon bags. Thirty-one VOC with a wide range of volatility and persistency were identified from processed paper. The total VOC emission from the various types of paper differed substantially. Using the field and laboratory emission cell (FLEC), the calculated initial emission rate of styrene was 5 μg m?2h?1 from a freshly processed paper The VOC emission from machines and the processed paper can be reduced by proper choice of o m e equipment. However, an evaluation should consider all potential pollutants. 相似文献
23.
The Mini-University program, which introduces Canadian school children (aged 10–16 yrs) to academic and sports/recreational activities during the summer session, is discussed in terms of its value. Specifically, the program is viewed as an opportunity for fostering an understanding of the discipline of psychology. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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An analytical expression is derived from the equation of diffusion with a reversible reaction which allows the direct calculation of diffusion, mass transfer and kinetic coefficients from transient experiments in slurry reactors. A similar expression is obtained for the case when the slurry volume size is finite. These expressions are then used to calculate the diffusion coefficient and surface mass transfer coefficients of radioiodinated Bovine Serum Albumin desorbing from gel beads made of agarose and suspended in an aqueous slurry. 相似文献
26.
F. D. Gunstone Gillian M. Taylor J. A. Cornelius T. W. Hammonds 《Journal of the science of food and agriculture》1968,19(12):706-709
The component acids of seed oils from over fifty legumes and over fifty other species are reported, and their potential value is discussed. 相似文献
27.
This paper reports the application of ampholyte-based isoelectric focusing in poly(dimethylsiloxane) (PDMS) using methylcellulose (MC) to reduce electroosmosis and peak drift. Although the characteristics of PDMS make it possible to fabricate microfluidic chips using soft lithography, unstable electroosmotic flow (EOF) and cathodic drift are significant problems when this medium is used. This paper demonstrates that EOF is greatly reduced in PDMS by applying a dynamic coat of MC to the channel walls and that higher concentrations of MC can be used to increase the viscosity of the electrode solutions in order to suppress pH gradient drift and reduce "compression"of the pH gradient. To illustrate the effect of MC on performance, several fluorescent proteins were focused in microchip channels 5 microm deep by 300 microm wide by 2 cm long in 3-10 min using broad-range ampholytes at electric field strengths ranging from 25 to 100 V/cm. 相似文献
28.
Stephan Pachnicke Sinan Özdür Helmut Griesser Cornelius Fürst Peter M. Krummrich 《Optical Fiber Technology》2009,15(5-6):414-419
The sensitivity of optical orthogonal-frequency division multiplexing (OFDM) transmission to the finite resolutions of the digital-to-analog (DAC) and analog-to-digital converters (ADC) has been analyzed using numerical simulations. We show that for back-to-back configuration the requirements regarding the number of quantization bits for the DACs are similar to the ones of the ADCs. After transmission over metro and long-haul distances a higher resolution of the DAC/ADC is required compared to back-to-back configuration. We show that after transmission it is sufficient to enhance either the ADC resolution or the DAC resolution by 1 bit. 相似文献
29.
Elise E. Switzer Tim S. Olson Plamen Atanassov Christopher J. Cornelius 《Electrochimica acta》2009,54(3):989-8003
In this work, we have investigated an aerosol-derived templated electrocatalyst for electro-oxidation of small organic molecules in alkaline media. Templated Pt-Sn electrocatalysts are compared to templated Pt catalysts both synthesized in an aerosol synthesis technique. In this synthesis approach, mono-disperse silica nanoparticles are used to template the metallic precursors. Structural and compositional analysis of the nanostructured materials are performed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and BET surface area measurements. The aerosol-derived templated electrocatalysts are examined in conjunction with an anion exchange ionomer for ethanol, methanol and CO oxidation in alkaline media. The electrochemical studies include cyclic voltammetry, chronoamperometry and voltammetric adsorption of adsorbed CO. 相似文献
30.
Calabrese V Bates TE Mancuso C Cornelius C Ventimiglia B Cambria MT Di Renzo L De Lorenzo A Dinkova-Kostova AT 《Molecular nutrition & food research》2008,52(9):1062-1073
Free radicals play a main pathogenic role in several human diseases such as neurodegenerative disorders, diabetes, and cancer. Although there has been progress in treatment of these diseases, the development of important side effects may complicate the therapeutic course. Curcumin, a well known spice commonly used in India to make foods colored and flavored, is also used in traditional medicine to treat mild or moderate human diseases. In the recent years, a growing body of literature has unraveled the antioxidant, anticarcinogenic, and antinfectious activity of curcumin based on the ability of this compound to regulate a number of cellular signal transduction pathways. These promising data obtained in vitro are now being translated to the clinic and more than ten clinical trials are currently ongoing worldwide. This review outlines the biological activities of curcumin and discusses its potential use in the prevention and treatment of human diseases. 相似文献