• International Journal of Naval Architecture and Ocean Engineering
• /
• v.5 no.4
• /
• pp.529-545
• /
• 2013

Strong restrictions on emissions from marine power plants (particularly $SO_x$, $NO_x$) will probably be adopted in the near future. In this paper, a combined solid oxide fuel cell (SOFC) and gas turbine fuelled by natural gas is proposed as an attractive option to limit the environmental impact of the marine sector. It includes a study of a heat-recovery system for 18 MW SOFC fuelled by natural gas, to provide the electric power demand onboard commercial vessels. Feasible heat-recovery systems are investigated, taking into account different operating conditions of the combined system. Two types of SOFC are considered, tubular and planar SOFCs, operated with either natural gas or hydrogen fuels. This paper includes a detailed thermodynamic analysis for the combined system. Mass and energy balances are performed, not only for the whole plant but also for each individual component, in order to evaluate the thermal efficiency of the combined cycle. In addition, the effect of using natural gas as a fuel on the fuel cell voltage and performance is investigated. It is found that a high overall efficiency approaching 70% may be achieved with an optimum configuration using SOFC system under pressure. The hybrid system would also reduce emissions, fuel consumption, and improve the total system efficiency.

• Biomedical Science Letters
• /
• v.10 no.2
• /
• pp.121-128
• /
• 2004

Mast cells and goblet cells have the ability to protect against parasites by increasing mucus production that traps and excludes worms and prevents their intimate contact with the gut mucosa in the host. In this study, we investigated the function of mast cells and goblet cells for the rejection of Echinostoma hortense (E. hortense). In addition, we used both C3H/HeN and BALB/c mice in order to examine whether mast cells and goblet cells function differentially according to the strains of mice. After an oral infection with 30 E. hortense metacercariae, the number of mucosal mast cells and goblet cells, as well as worm recovery rate, were observed in experimentally infected mice between 1 week and 8 weeks post-infection (PI). Worm recovery rates in C3H/HeN and BALB/c mice were 65.7％ and 23％, respectively, in week 1 P.I., indicating that worm expulsion in C3H/HeN mice was higher than in BALB/c mice. Our results demonstrate that the period (week 3 P.I.) in which worm recovery falls rapidly is the same period that the number of goblet cells and mast cells reaches a peak. These results indicate that worm recovery significantly correlates with the growth rate of goblet cells and mast cells (P=0.0482). However, worm expulsion is not associated with goblet cells or mast cells in BALB/c mice.

• Journal of Microbiology and Biotechnology
• /
• v.21 no.9
• /
• pp.954-959
• /
• 2011

There have been a number of studies conducted in order to compare the efficiencies of recovery rates, utilizing different protocols, for the isolation of L. monocytogenes. However, the severity of multiple cell injury has not been included in these studies. In the current study, L. monocytogenes ATCC 19112 was injured by exposure to extreme temperatures ($60^{\circ}C$ and $-20^{\circ}C$) for a one-step injury, and for a two-step injury the cells were transferred directly from a heat treatment to frozen state to induce a severe cell injury (up to 100% injury). The injured cells were then subjected to the US Food and Drug Administration (FDA), the ISO-11290, and the modified United States Department of Agriculture (mUSDA) protocols, and plated on TSAyeast (0.6% yeast), PALCAM agar, and CHROMAgar Listeria for 24 h or 48 h. The evaluation of the total recovery of injured cells was also calculated based on the costs involved in the preparation of media for each protocol. Results indicate that the mUSDA method is best able to aid the recovery of heat-injured, freeze-injured, and heat-freeze-injured cells and was shown to be the most cost effective for heat-freeze-injured cells.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.29 no.2
• /
• pp.68-73
• /
• 2017

Recently, energy recovery ventilators (ERVs) have been installed for energy saving in many multi-residential buildings in Korea. The performance of the heat exchanger of an ERV is analyzed in this study under specific indoor and outdoor conditions in a test-cell measurement. However, the performance of the heat exchanger varies according to the indoor and outdoor condition. In this study, the performance of energy recovery of the ventilation system was therefore analyzed in actual weather conditions using field measurement. Experiments were conducted under winter conditions in a multi-residential building for 20 days. Based on the measurement results, the characteristics of sensible heat and latent heat exchange rates were analyzed.

• Journal of Microbiology and Biotechnology
• /
• v.19 no.10
• /
• pp.1230-1237
• /
• 2009

The selective plugging strategy of Microbial Enhanced Oil Recovery (MEOR) involves the use of microbes that grow and produce exopolymeric substances, which block the high permeability zones of an oil reservoir, thus allowing the water to flow through the low permeability zones leading to increase in oil recovery. Bacillus licheniformis TT33, a hot water spring isolate, is facultatively anaerobic, halotolerant, and thermotolerant. It produces EPS as well as biosurfactant and has a biofilm-forming ability. The viscosity of its cell-free supernatant is $120\;mPa{\cdot}s$ at $28^{\circ}C$. Its purified EPS contained 26% carbohydrate and 3% protein. Its biosurfactant reduced the surface tension of water from 72 to 34 mN/m. This strain gave $27.7{\pm}3.5%$ oil recovery in a sand pack column. Environmental scanning electron microscopy analysis showed bacterial growth and biofilm formation in the sand pack. Biochemical tests and Amplified Ribosomal DNA Restriction Analysis confirmed that the oil recovery obtained in the sand pack column was due to Bacillus licheniformis TT33.

• Journal of Ginseng Research
• /
• v.46 no.5
• /
• pp.646-656
• /
• 2022

Background: In addition to its use as a health food, ginseng is used in cosmetics and shampoo because of its extensive health benefits. The ginsenoside, Rh2, is a component of ginseng that inhibits tumor cell proliferation and differentiation, promotes insulin secretion, improves insulin sensitivity, and shows antioxidant effects. Methods: The effects of Rh2 on cell survival, extracellular matrix (ECM) protein expression, and cell differentiation were examined. The antioxidant effects of Rh2 in UV-irradiated normal human dermal fibroblast (NHDF) cells were also examined. The effects of Rh2 on mitochondrial function, morphology, and mitophagy were investigated in UV-irradiated NHDF cells. Results: Rh2 treatment promoted the proliferation of NHDF cells. Additionally, Rh2 increased the expression levels of ECM proteins and growth-associated immediate-early genes in ultraviolet (UV)-irradiated NHDF cells. Rh2 also affected antioxidant protein expression and increased total antioxidant capacity. Furthermore, treatment with Rh2 ameliorated the changes in mitochondrial morphology, induced the recovery of mitochondrial function, and inhibited the initiation of mitophagy in UV-irradiated NHDF cells. Conclusion: Rh2 inhibits mitophagy and reinstates mitochondrial ATP production and membrane potential in NHDF cells damaged by UV exposure, leading to the recovery of ECM, cell proliferation, and antioxidant capacity.

• Journal of Environmental Science International
• /
• v.5 no.3
• /
• pp.317-327
• /
• 1996

This study was performed to develop the biological treatment technology of wastewater polluted with heavy metals. Zinc-tolerant microorganism, such as Pseudomonas chlororaphis which possessed the ability to accumulate zinc, was isolated from industrial wastewaters polluted with various heavy metals. The characteristics of zinc accumulation in the cells, recovery of the zinc from the cells accumulating zinc, were investigated. Removal rate of zinc from the solution containing 100 mall of Zinc by zinc-tolerant microorganism was more than 90% at 48 hours after inoiulation of the microorganisms. A large number of the electron-dense granules were found mainly on thIn cell wall and membrane fractions, when determined by transmission electron microscope. Energy dispersive X- ray spectroscopy revealed that the electron-dense granules were zinc complex with the substances binding Heavy metals. The zinc accumulated into cells was not desorbed by distilled water, but more than 80% of the zinc accumulated was desorbed by 0.1M-EDTA. The residues of the cells after combustion at 55$0^{\circ}C$ amounted to about 21% of the dry weight of the cells. EDS analysis showed that the residues were comparatively pure zinc compounds containing more than 79% of zinc.

• Korean Journal of Veterinary Pathology
• /
• v.7 no.1
• /
• pp.11-15
• /
• 2003

Antigen retrieval (AR) techniques were widely used to recover the antigenicity from the fixed tissues, which were guided by the philosophy of rendering immunohistochemistry (IHC) applicable to routine formalin-fixed, paraffin-embedded tissues for wide application of IHC in research and clinical filed for morphological observation like as anatomy, histology and pathology. Protease antigen recovery (PAR) is an AR technique, which is obtained the antigen retrieve by using enzyme digestion, and commonly used in IHC field. However, during the IHC for the detection of ovine herpesvirus 2 (OvHV-2) antigen, we noted lymphocyte-like cells-specific staining in the infiltrated cells into various organs like as liver and kidney, which was also shown in the IHC tissues with isotype control. However, those signals were not observed in the tissues conducted with in situ hybridization. Therefore, we analyzed the specificity of the IHC detection results. We found that PAR may induce false-positive result during IHC in lymphocyte-like cells, which were infiltrated mainly around vessels and in interstitial tissues. Through the Phenotyping, we realized that those false-positive cells were B-cell-related cells. These results suggest that PAR, a AR using protease, may induce non-specific false-positive reactions during IHC.

• Membrane Journal
• /
• v.12 no.3
• /
• pp.165-170
• /
• 2002

Membrane process was investigated to recover useful components, such as protein from rice-washing water generated in the production of the washed-rice. The filtration experiments were carried out using not only a dead-end Amicon cell to determine suitable membranes but also a hollow fiber ultrafiltration, spiral wound nanofiltration and reverse osmosis modules for home water purification. Ultrafiltration module(molecular weight cut-off : 10,000 dalton) was not suitable for recovery of useful components or protein in the rice-washing water, but nanofiltration and reverse osmosis modules showed a good performance. in the case of 250% concentration of the rice-washing water contained about 9% protein the proteins in concentrates of nanofiltration and reverse osmosis were 18% and 22%, which were about 2 and 2.4 times higher protein concentrations than those of feed, respectively.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2015.10a
• /
• pp.842-846
• /
• 2015

In this study, we propose an algorithm of the method of recovering quickly find the location of the error encountered during separate operations in the functional structure of complex digital circuits by mimicking the self-healing function of the cell. By the digital circuit was divided by 9 function block unit of function, proposes a method that It can quickly detect and recover the error position. It was the detection and recovery algorithms for the error location in the digital circuit of a complicated structure and could extended the number of function block for the $3{\times}3$ matrix structure on the digital circuit.