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Change in the color of heat‐treated,vacuum‐packed broccoli stems and florets during storage: effects of process conditions and modeling by an artificial neural network 下载免费PDF全文
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Two dimensional standards are important materials which are used in the calibration and the verification of coordinate measuring machines. In several countries, the national metrology institutes or accredit laboratories provide the calibration services of the two dimensional standards such as ball plates, hole plates and grid plates. The metrological equivalence of the measurement standards among the calibration providers is validated through the key comparison program. In the previous key comparison for a ball plate and a hole plate, the equivalences among the participants’ calibration results were verified on the distances between the No. 1 ball/hole (i.e., the origins of the workpiece coordinates) and other balls/holes on the plates respectively. The essential measurands of the two dimensional standards are the coordinates of the feature points, however, the measurement equivalences on them have not been verified. In this study, the authors propose the coordinates-based evaluation of the reference values and their uncertainty in two dimensional standard calibration comparison. 相似文献
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Radicals generated in plastic medical devices (solid phase) by γ-rays or electron-beam irradiation during sterilization are known to cause oxidation of protein drugs, resulting in a loss or reduction in drug efficacy. The generation of radical species in water by the radical species in solid polymers has not been proved. Using electron spin resonance (ESR) spectroscopy, we confirm the generation of new radicals in water by γ-ray irradiated cyclic olefin polymers (COP). ESR measurements are obtained using 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPOL) as a spin probe and 5-(2,2-dimethyl-1,3-propoxycyclophosphoryl)-5-methyl-1-pyrroline N-oxide (CYPMPO) as a spin trap, in which the irradiated COP was immersed. The ESR signals indicate the TEMPOL radicals decline over time, suggesting the generation of new radicals. Conversely, the characteristic ESR signals of the adduct formed by the reaction between CYPMPO and the hydroxyl radical are observed. Thus, hydroxyl radicals are generated because of the migration of the radicals from COP to water. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48604. 相似文献
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Watanabe Masahito Sato Fumiya Abe Raiki Ueda Kyosuke Matsuwaka Daisuke Kudo Fumiaki Narushima Takayuki 《Metallurgical and Materials Transactions B》2019,50(4):1553-1558
Metallurgical and Materials Transactions B - A two-step plasma arc melting process, comprising a first step under Ar-30 pct H2 gas flow and the second step under Ar gas flow, has been... 相似文献
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Neural Processing Letters - Political optimizer (PO) is a recently proposed human-behavior inspired meta-heuristic, which has shown tremendous performance on complex multimodal functions as well as... 相似文献