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951.
Keun Ho Choi Won Kook Lee 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1993,56(1):51-58
The effects of the horizontal connection length (0.1 ± Le ± 0.5 m), the cross-sectional area ratio of downcomer-to-riser (0.11 ± Ad/Ar± 0.53), and the superficial gas velocity on gas phase holdups in the riser and downcomer were studied. The circulation liquid velocity, the mixing performance and the volumetric mass transfer coefficient in the external-loop airlift reactors were also measured. The horizontal connection length and Ad/Ar were major parameters which strongly affected the performance of external-loop airlift reactors. Useful correlations in the external-loop airlift reactors were obtained for gas holdups, the volumetric mass transfer coefficient, the circulation liquid velocity, and the mixing time. 相似文献
952.
Glomerular diseases are associated with changes in glomerular membrane permeability properties that alter filtration rate of plasma water and barrier function of the capillary wall. To estimate intrinsic permeability properties that regulate transmembrane transport of water and macromolecules, theoretical analysis of renal clearance of tracer molecules can be used. The development of adequate theoretical models is required to achieve sufficient accuracy to simulate complicated biological processes. Current research in this area is aimed at improving and validating the presently available models in order to characterize the nature of permeability changes associated with pathological conditions. This is a key step in understanding the pathophysiological nature of glomerular diseases and in the development of effective treatments. 相似文献
953.
Won Sik Youn Chong Kwan Un 《Signal Processing, IEEE Transactions on》1994,42(6):1543-1547
In a linearly constrained beamformer with imperfect arrays, the authors investigate the cause of cancelling the desired signal from a viewpoint based on the eigenstructure properties of the array covariance matrix. Based on this cause, they propose a robust beamforming algorithm. As an adaptive algorithm of the proposed beamformer, the present a data-domain signal subspace updating algorithm 相似文献
954.
Surface heat transfer coefficient values were measured for polycrystalline alumina quenched into water, into oil, and into liquid nitrogen. Since the measurements of the surface heat transfer coefficient h for alumina (and ceramics in general) are very limited, we compare our measurements with calculations of h for the water quench and with measurements of h on non-ceramic materials for the oil and liquid nitrogen quenches. 相似文献
955.
Mendoza Remilyn M. Kim Sang Hoon Vasquez Robie Hwang In-Chan Park Young-Seo Paik Hyun-Dong Moon Gi-Seong Kang Dae-Kyung 《Food science and biotechnology》2023,32(4):389-412
Food Science and Biotechnology - Due to their numerous well-established applications in the food industry, there have been many studies regarding the adaptation and evolution of lactic acid... 相似文献
956.
C. Basavaraja Won Jung Kim Dae Gun Kim P.X. Thin Do Sung Huh 《Polymer Composites》2011,32(7):1077-1085
A composite of poly(N‐vinylcarbazole) (PVK) containing gold nanoparticles (GNPs) was synthesized via simple solid‐state in situ bulk polymerization of N‐vinylcarbazole in the presence of GNPs at a high temperature. Both PVK and PVK–GNP composites were characterized by Fourier transform infrared (FTIR) and UV–vis spectroscopy. The surface morphology of the composites was studied by scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy, and transmission electron microscopy (TEM). Thermal stability was identified via thermogravimetric analysis. The composites were fabricated into films using the Langmuir–Schaefer process. The enhancement in the characteristics of room temperature I–V, pressure–area isotherms, and photoelectrochemical behaviors was observed in the composite films. Results suggest that a charge transfer process occurs across the hybrid at the interface of the PVK–GNP composites. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers 相似文献
957.
The effect of fermentation with Pediococcus pentosaceus at different temperatures ranging from 15 to 37 °C on the quality characteristics of silver carp sausages was investigated. Higher temperature stimulated the rapid growth of lactic acid bacteria, resulting in a rapid decline in pH, and consequently suppressed the growth of Pseudomonas, Micrococcaceae and Enterobacteriaceae. However, increasing fermentation temperature gave a progressive increase in total volatile basic nitrogen and biogenic amines in fermented silver carp sausages. Histamine was the main biogenic amine, exceeding 100 mg/kg after 48 h of fermentation at temperatures above 30 °C. Higher content of non-protein nitrogen and α-amino nitrogen correlated with the electrophoretic studies, which showed that proteolysis of high molecular weight myofibrillar and sarcoplasmic proteins was more prominent at higher fermentation temperatures. Products fermented at 23–30 °C showed greatest consumer preference and most favourable textural properties. 相似文献
958.
The flavor and taste of coffee are the most important criteria for evaluating its quality and they are influenced by environmental as well as genetic factors. Because of these factors, including soil, climate and species, diverse components of coffee have been developed. To observe the variation of coffee components by region, a metabolomic approach was applied. In this study, 21 coffee samples of different origin were analyzed by various measuring devices. The acquired data was then integrated and processed by principal component analysis (PCA) using SAS 9.1 software. We found that we could successfully identify the origins of the coffee, dividing the samples in the regions of Asia, South America, and Africa, using the integrated metabolomic approach of combining diverse analytical data with multivariate analysis. In particular, the enhancement of subtle differences by combining data from several instruments resulted in the accurate discrimination of coffee origins. 相似文献
959.
Lee SG Bak JG Nam UW Moon MK Shi Y Bitter M Hill K 《The Review of scientific instruments》2010,81(10):10E506
The x-ray imaging crystal spectrometer (XICS) for the Korea Superconducting Tokamak Advanced Research has been first applied for the experimental campaign in 2009. The XICS was designed to provide measurements of the profiles of the ion and electron temperatures from the heliumlike argon (Ar XVII) spectra. The basic functions of the XICS are properly working although some satellites lines are not well matched with the expected theoretical values. The initial experimental results from the XICS are briefly described. 相似文献
960.
Ki Won Sung Chae Y. Lee Kwang Hyuk Yim Agnes Gravrand 《Wireless Personal Communications》2009,50(4):469-481
Traffic asymmetry between uplink and downlink is expected to be a remarkable 3G characteristic in cellular mobile multimedia
communications. CDMA system with TDD is a good solution to this traffic asymmetry. However, the level of traffic asymmetry
may be significantly different from a cell to another cell. To tackle this problem and to support the traffic hot spot, crossed
slots are examined. The use of crossed slots is restricted within a certain range of a cell by investigating the inter-cell
interference and the maximum planned load factor. We examine the radius of inner zone and discuss the capacity of downlink
crossed slots for various neighbor cell environments. Computational results show that the capacity increase in the target
cell is outstanding by reducing the service range of neighbor cells. When all six neighbors reduce their service range by
20%, the capacity at target cell crossed slot is increased by 35%. Monte Carlo simulation is performed with large scale fading
to verify the numerical analysis.
相似文献
Chae Y. LeeEmail: |