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751.
752.
Khfagi Amir Mohamed Hunt Graeme Paul Manosh C. Karimi Nader 《Journal of Thermal Analysis and Calorimetry》2022,147(21):12093-12110
Journal of Thermal Analysis and Calorimetry - This work investigates heat transfer and entropy generation of a turbulent flow of an Al2O3–Cu/water hybrid nanofluid in a plain tube (PT) with... 相似文献
753.
754.
Vasilev K Zhu T Wilms M Gillies G Lieberwirth I Mittler S Knoll W Kreiter M 《Langmuir : the ACS journal of surfaces and colloids》2005,21(26):12399-12403
A simple procedure to synthesize gold nanowires based on the reduction of hydrogen tetrachloroaurate by 2-mercaptosuccinic acid in aqueous solution is presented. This procedure requires no additional capping or reduction agent and produces wires with an apparent curly morphology several micrometers in length with diameters as thin as 15 nm. Some of the wires produced end in a ribbonlike structure, finally terminated by a flat triangular prism. Investigations by scanning electron microscopy, transmission electron microscopy (bright and dark field), scanning transmission electron microscopy, and atomic force microscopy as well as conductivity measurements indicate fully connected, polycrystalline gold objects. 相似文献
755.
THE DEVELOPMENT OF PERSONAL DOSIMETERS FOR USE IN THE VISIBLE AND ULTRAVIOLET WAVELENGTH REGIONS 总被引:1,自引:0,他引:1
D. D. Duncan W. Schneider K. J. West S. J. Kirkpatrick S. K. West 《Photochemistry and photobiology》1995,62(1):94-100
Abstract—
We have designed, developed, and field evaluated a two-part personal dosimeter for estimating ocular exposure to visible and ultraviolet radiation. The detector head is compact enough to be mounted on the bow of eyeglass frames, and the recorder is small enough to be carried in a shirt pocket. The detector head consists of a silicon photodiode with filter (Schott glass GG400) and diffuser for visible light measurements and a polysulphone film badge for ultraviolet-B (UVB, 290–320 nm) measurements. The measurements correspond well to those obtained using ambient monitors and should be useful for studies of ocular UVB exposure. 相似文献
We have designed, developed, and field evaluated a two-part personal dosimeter for estimating ocular exposure to visible and ultraviolet radiation. The detector head is compact enough to be mounted on the bow of eyeglass frames, and the recorder is small enough to be carried in a shirt pocket. The detector head consists of a silicon photodiode with filter (Schott glass GG400) and diffuser for visible light measurements and a polysulphone film badge for ultraviolet-B (UVB, 290–320 nm) measurements. The measurements correspond well to those obtained using ambient monitors and should be useful for studies of ocular UVB exposure. 相似文献
756.
Cooke G Garety JF Hewage SG Rabani G Rotello VM Woisel P 《Chemical communications (Cambridge, England)》2006,(39):4119-4121
Mixed monolayer protected gold nanoparticles have been fabricated incorporating 1,5-dialkyloxynaphthalene moieties that are capable of forming complexes with the tetracationic cyclophane cyclobis(paraquat-p-phenylene); electrochemical reduction of the cyclophane or the addition of tetrathiafulvalene results in disassembly of the complexes. 相似文献
757.
Graeme L. Blackman Ronald D. Brown Roger F.C. Brown Frank W. Eastwood Gabrielle L. McMullen 《Journal of Molecular Spectroscopy》1977,68(3):488-491
The microwave spectrum of methylene ketene has been observed from 8 to 35 GHz and assigned. Rotational constants and centrifugal distortion constants have been determined for CH2CCO, CHDCCO, and CD2CCO. The dipole moment was found to be μa = 2.14 ± 0.06 D (7.07 ± 0.2 × 10?30 Cm). We were unable to detect propynal among the pyrolysis products of acrylic anhydride. This pyrolysis proved to be the most convenient route for generating methylene ketene for the present investigation. 相似文献
758.
Long-ranged, or power-law, behavior of correlation functions in both space and time is discussed for classical systems and for quantum systems at finite temperature, and is compared with the corresponding behavior in quantum systems at zero temperature. The origin of the long-ranged correlations is explained in terms of soft modes. In general, correlations at zero temperature are of longer range than their finite-temperature or classical counterparts. This phenomenon is due to additional soft modes that exist at zero temperature. 相似文献
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760.
Clinical functional magnetic resonance imaging (fMRI) occasionally fails to detect significant activation, often due to variability in task performance. The present study seeks to test whether a more flexible statistical analysis can better detect activation, by accounting for variance associated with variable compliance to the task over time. Experimental results and simulated data both confirm that even at 80% compliance to the task, such a flexible model outperforms standard statistical analysis when assessed using the extent of activation (experimental data), goodness of fit (experimental data), and area under the operator characteristic curve (simulated data). Furthermore, retrospective examination of 14 clinical fMRI examinations reveals that in patients where the standard statistical approach yields activation, there is a measurable gain in model performance in adopting the flexible statistical model, with little or no penalty in lost sensitivity. This indicates that a flexible model should be considered, particularly for clinical patients who may have difficulty complying fully with the study task. 相似文献