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21.
我们把注意力投向了“自然意志”之间悖论性的循环机制,在这种机制下从jungrang溪冲积下来的淤沙创造了岛屿,而人们为了控制洪水不断努力地清理着这些淤泥。我们同时无意间揭示了一个事实,疏清出来的淤泥被归为一种“工业废弃物”。我们希望做的是利用这种由溪流不断提供的将汉江与首尔之城重新联系的自然资源。虽然我们始自虚无,希冀的却是那无穷的扩展。我们相信自己在这个项目的场地中所做的工作会扩展到超过其预期的尺度。 相似文献
22.
MASASHI KOTARI TOMO TADOKORO SHIN‐ICHI TANAKA MIKIMASA IWATA TADASHI AMAKAWA 《Electrical Engineering in Japan》2016,195(3):26-37
From an environmental viewpoint, when carrying out internal arc tests on SF6‐insulated power equipment, it is necessary to prevent SF6 from being released into the atmosphere or to replace SF6 with air in accordance with IEC standards. However, the pressure rise and the thermal effect of the hot gas exhausted during arcing when testing in air are still considerably different from those for testing in SF6. Thus, it is necessary to propose a specific procedure to replace SF6 with air and to select appropriate parameters for the tests. Therefore, it is desirable to clarify the equivalent conditions causing these phenomena both experimentally and analytically. In this paper, we describe the effect of the charged gas pressure in a closed container on the pressure rise due to air and SF6 arcing and the ratio of the arc energy to the energy contributing to the internal pressure rise () from an experimental viewpoint. Additionally, to research the energy balance resulting from SF6 arcing in the container, the energy balance is discussed on the basis of chemical reactions, radiation, and the melting and vaporization of the electrodes. It is found that the maximum pressure rise increases for both gases upon increasing the gas pressure from 0.1 MPa to 0.4 MPa. Subsequently, good agreement with the energy balance was obtained under reasonable assumptions by taking account of the energy components related to the chemical reactions, radiation, and the melting and vaporization of the electrodes. The ratio of the radiation energy loss to the total consumption energy increased upon increasing the charged gas pressure. 相似文献
23.
A scheme for intelligent optimization and control of complex manufacturing processes is presented. The underlying nonlinear process is modelled by artificial neural networks and process control is performed by fuzzy logic. Fuzzy rules are automatically generated from the trained neural networks through a novel rule generation mechanism and fuzzy control is performed by Mamdani implication. Simulation results show that the proposed approach can provide a robust and accurate way of controlling complex processes without comprehensive models or knowledge about the process. 相似文献
24.
J. H. LEE M. R. KIM I. H. KIM H. KIM J. A. SHIN K. T. LEE 《Journal of food science》2004,69(2):fct89-fct95
ABSTRACT: Structured lipid (SL) from conjugated linoleic acid (CLA) with olive oil was produced, and the physicochemical and volatile characterizations were investigated. In SL-olive oil, 21.8 mol% of CLA isomers were incorporated, and the removal of tocopherols (63% loss from original olive oil) and chlorophylls (50% loss) was observed. The distinct exothermal peaks observed became broader, and the position of the peak shifted to a lower temperature in SL-olive oil compared with normal olive oil. Reverse-phase (ODS column) high-performance liquid chromatography with an evaporative light-scattering detection separated the newly synthesized SL-triacylglycerols (TAGs), in which the incorporation of CLA into olive oil increased the content of TAGs with partition number <48 from 9% (in olive oil) to 78% (SL-olive oil). Total amount of volatile compounds in SL-olive oil was smaller than those in olive oil, indicating removal of flavor compounds from olive oil occurred during the processes. 相似文献
25.
SANGMIN SHIN JUNE MO KOO JUNE KEY LEE SUK PIL KIM CHOONG RAE CHO YOUNGSOO PARK 《Integrated ferroelectrics》2013,141(1):157-168
Pb(Zr,Ti)O3 (PZT) films grown on Ir electrodes by a metal-organic chemical vapor deposition (MOCVD) have suffered from high leakage and rough surface. We sputtered Pt and Ir simultaneously onto Ti/SiO2/Si substrates and formed Ir-Pt alloy bottom electrodes with various compositions. With an optimal composition of Ir and Pt, PZT films grown by MOCVD on this substrate showed smoother surface and suppressed leakage via the bottom interface. At the specific composition of Ir and Pt, two different phases seemed to be acquired. They constituted the electrodes and affected the PZT grain nucleation independently so that the grains with different origins grew and restrained the vicinal grains, and finally soothed the faceted-grain-formation. No fatigue was observed even in PZT on Ir-Pt alloy with much Pt content. 相似文献
26.
D. C. KIM S. SEO D.-S. SUH R. JUNG C. W. LEE J. K. SHIN 《Integrated ferroelectrics》2013,141(1):90-97
ABSTRACT Experimental investigations on the resistive memory switching in sub-micron sized NiO memory cell are presented to elucidate the resistive memory switching mechanism. The voltage or current-biased I-V measurements show that the resistive switching transitions can be regarded as the combination of a voltage-controlled negative differential resistance phenomenon and a current-controlled negative differential resistance phenomenon. Along with experimental observations of multiple resistance states, these indicate that the memory switching in NiO would come from the percolative formation and rupture of filamentary conducting paths. Pulse experiments further suggest that the memory switching would come from local domains inside filaments. 相似文献
27.
Test results are presented for short floating ring seals (D = 53.0 mm, L/D = 0.15) using a smooth surface and a round-hole pattern defined as a damper floating ring seal (h/Cr = 3, γ = 0.34: the ratio of hole area to surface area) for supplied pressures of 3.0, 5.0, and 7.0 MPa, respectively, with the shaft operating speed up to 24,800 rpm. The measured data includes leakage, attitude angle, eccentricity ratio, and rotordynamic coefficients such as stiffness, damping, and inertia. When the floating ring seals are locked up, the eccentricity ratio of the smooth surface floating ring seal is lower than that of the damper floating ring seal. The attitude angle increases linearly with the operating speeds. The damping coefficients of the damper floating ring seal are higher than those of the floating ring seal. Whirl frequency ratios of the floating ring seal are lower than the damper floating ring seal with high eccentricity ratio at low operating speed range. The design parameters determined from these test results will be used for high-pressure and high-speed turbopump seals in a liquid rocket engine system. 相似文献
28.
Plasmonic nanogap-enhanced Raman scattering has attracted considerable attention in the fields of Raman-based bioanalytical applications and materials science. Various strategies have been proposed to prepare nanostructures with an inter- or intra-nanogap for fundamental study models or applications. This report focuses on recent advances in synthetic methods to fabricate intra-nanogap structures with diverse dimensions, with detailed focus on the theory and bioanalytical applications. Synthetic strategies ranging from the use of a silica layer to small molecules, the use of polymers and galvanic replacement, are extensively investigated. Furthermore, various core structures, such as spherical, rod-, and cube-shaped, are widely studied, and greatly expand the diversity of plasmonic nanostructures with an intra-nanogap. Theoretical calculations, ranging from the first plasmonic hybridization model that is applied to a concentric Au–SiO2–Au nanosphere to the modern quantum corrected model, have evolved to accurately describe the plasmonic resonance property in concentric core–shell nanostructures with a subnanometer nanogap. The greatly enhanced and uniform Raman responses from the localized Raman reporter in the built-in nanogap have made it possible to achieve promising probes with an extraordinary high sensitivity in various formats, such as biomolecule detection, high-resolution cell imaging, and an in vivo imaging application. 相似文献
29.
Nomilin acetyl-lyase, an enzyme responsible for the conversion of bitter nomilin to nonbitter obacunone was purified from cell-free extracts of Corynebacterium fuscians by (NH4)2SO4 precipitation, followed by HPLC gel filtration and ion exchange chromatography. The electrophoretically pure preparation represented a 1050-fold increase in specific activity with a recovery of 38%. The enzyme, (MW 90,000) required sulfhydryl groups for its catalysis, had a pH optimum of 8.5, a Km of 38.1 PM, and a Vmax of 4.83 μmoles/min. Obacunone A-ring lactone hydrolase, which catalyzes the conversion of obacunone to obacunoate, was also purified from the extract by HPLC gel filtration. 相似文献
30.
Hydrolytic Stability and Changes in E Vitamers and Oryzanol of Extruded Rice Bran During Storage 总被引:4,自引:0,他引:4
TAI-SUN SHIN J. SAMUEL GODBER DANIEL E. MARTIN JOHN H. WELLS 《Journal of food science》1997,62(4):704-728
Rice bran was extruded at 110, 120, 130, and 140°C with post extrusion holding times of 0, 3, and 6 min and stored at ambient temperatures for 1 yr. Holding time had no effect (p>0.05) on hydrolytic stability whereas 110°C was slightly less effective in maintaining hydrolytic stability. Increased holding times reduced (p<0.05) total vitamin E content. Oryzanol concentration was lower (p<0.05) only after 6 min holding time. Oryzanol was relatively more stable to extrusion temperatures than vitamin E. The highest retentions of total vitamin E and oryzanol were found in raw rice bran during storage. Increased extrusion temperatures reduced the retention of vitamin E and oryzanol during storage. 相似文献