• Tuberculosis and Respiratory Diseases
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• v.45 no.6
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• pp.1236-1251
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• 1998

Background : TNF-$\alpha$ appears to be a central mediator of the host response to sepsis. While TNF-$\alpha$ is mainly considered a proinflammatory cytokine, it can also act as a direct cytotoxic cytokine. However, there are not so many studies about the relationship bet ween TNF-$\alpha$ level and lung injury severity in ALI, particularly regarding the case of ALI caused by direct lung injury such as diffuse pulmonary infection. Recently, a natural defense mechanism, known as the stress response or the heat shock response, has been reported in cellular or tissue injury reaction. There are a number of reports examining the protective role of pre-induced heat stress proteins on subsequent LPS-induced TNF-$\alpha$ release from monocyte or macrophage and also on subsequent LPS-induced ALI in animals. However it is not well established whether the stress protein synthesis such as HSP can be induced from rat alveolar macrophages by in vitro or in vivo LPS stimulation. Methods : We measured the level of TNF-$\alpha$, the percentage of inflammatory cells in bronchoalveolar lavage fluid, protein synthesis in alveolar macrophages isolated from rats at 1, 2, 3, 4, 6, 12, and 24 hours after intratracheal LPS instillation. We performed histologic examination and also obtained histologic lung injury index score in lungs from other rats at 1, 2, 3, 4, 6, 12, 24 h after intratracheal LPS instillation. Isolated non-stimulated macrophages were incubated for 2 h with different concentration of LPS (0, 1, 10, 100 ng/ml, 1, or 10 ${\mu}g/ml$). Other non-stimulated macrophages were exposed at $43^{\circ}C$ for 15 min, then returned to at $37^{\circ}C$ in 5% CO2-95% for 1 hour, and then incubated for 2 h with LPS (0, 1, 10, 100ng/ml, 1, or 10 ${\mu}g/ml$). Results : TNF-$\alpha$ levels began to increase significantly at 1 h, reached a peak at 3 h (P<0.0001), began to decrease at 6 h, and returned to control level at 12 h after LPS instillation. The percentage of inflammatory cells (neutrophils and alveolar macrophages) began to change significantly at 2 h, reached a peak at 6 h, began to recover but still showed significant change at 12 h, and showed insignificant change at 24 h after LPS instillation compared with the normal control. After LPS instillation, the score of histologic lung injury index reached a maximum value at 6 h and remained steady for 24 hours. 35 kDa protein band was newly synthesized in alveolar macrophage from 1 hour on for 24 hours after LPS instillation. Inducible heat stress protein 72 was not found in any alveolar macrophages obtained from rats after LPS instillation. TNF-$\alpha$ levels in supernatants of LPS-stimulated macro phages were significantly higher than those of non-stimulated macrophages(p<0.05). Following LPS stimulation, TNF-$\alpha$ levels in supernatants were significantly lower after heat treatment than in those without heat treatment (p<0.05). The inducible heat stress protein 72 was not found at any concentrations of LPS stimulation. Whereas the 35 kDa protein band was exclusively found at dose of LPS of 10 ${\mu}g/ml$. Conclusion : TNF-$\alpha$ has a direct or indirect close relationship with lung injury severity in acute lung injury or acute respiratory distress syndrome. In vivo and in vitro LPS stimulation dose not induce heat stress protein 72 in alveolar macrophages. It is likely that 35 kDa protein, synthesized by alveolar macrophage after LPS instillation, does not have a defense role in acute lung injury.

• Applied Chemistry for Engineering
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• v.19 no.5
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• pp.526-532
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• 2008

The proposed $CO_2$ storage technology in the present study is a one-step sequestration process that stabilizes $CO_2$ in a reactor with Serpentine. The advantage of this technology is associated with its high stability of final product so that the entire system is recognized as permanent environment-friendly $CO_2$ removal method. Since the sequestration reaction mechanisms are generally understood that carbonation reaction proceeds with very slow rate, so that pretreatment method to increases reaction rate of $CO_2$ carbonation reaction should be developed. To increase the reactivity of Serpentine with $CO_2$, two different methods of pretreatment are carried out in the present investigation. One is heat-treatment, the other is chemical pretreatment. In this study, only chemical pretreatment is considered leaching method of magnesium from Serpentine using sulfuric acid at the various reaction temperatures, times, and acid concentrations. Experimental results illustrated that pretreatment by sulfuric acid increases surface area of serpentine from $11.1209m^2/g$ to $98.7903m^2/g$ and extracts magnesium compounds. Single variable experiment demonstrated the enhancements of magnesium extraction with increased reaction temperature and time. Amount of magnesium extraction is obtained by using the data of ICP-AES as maximum extraction condition of magnesium is 2 M acid solution, $75^{\circ}C$ and 1hr. After performing chemical pretreatment, carbonation yield increased from 23.24% to 46.30% of weight.

• Corrosion Science and Technology
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• v.7 no.1
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• pp.50-60
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• 2008

The majority of the described experimental results deal with relatively pure aluminium. Variations were made in the pretreatment of the aluminum substrates and an investigation was performed on the resulting changes in oxide layer composition and chemistry. Subsequently, the bonding behavior of the surfaces was investigated by using model adhesion molecules. These molecules were chosen to represent the bonding functionality of an organic polymer. They were applied onto the pretreated surfaces as a monolayer and the bonding behavior was studied using infrared reflection absorption spectroscopy. A direct and clear relation was found between the hydroxyl fraction on the oxide surfaces and the amount of molecules that subsequently bonded to the surface. Moreover, it was found that most bonds between the oxide surface and organic functional groups are not stable in the presence of water. The best performance was obtained using molecules, which are capable of chemisorption with the oxide surface. Finally, it was found that freshly prepared relatively pure aluminum substrates, which are left in air, rapidly lose their bonding capacity towards organic functional groups. This can be attributed to the adsorption of contamination and water to the oxide surface. In addition the adhesion of a typical epoxy-coated aluminum system was investigated during exposure to water at different temperatures. The coating was found to quite rapidly lose its adhesion upon exposure to water. This rapid loss of adhesion corresponds well with the data where it was demonstrated that the studied epoxy coating only bonds through physisorptive hydrogen bonding, these bonds not being stable in the presence of water. After the initial loss the adhesion of the coating was however found to recover again and even exceeded the adhesion prior to exposure. The improvement could be ascribed to the growth of a thin oxyhydroxide layer on the aluminum substrate, which forms a new, water-stable and stronger bond with the epoxy coating. Two routes for improvement of adhesion are finally decribed including an interphasial polymeric thin layer and a treatment in boiling water of the substrate before coating takes place. The adhesion properties were finely also studied as a function of the Mg content of the alloys. It was shown that an enrichment of Mg in the oxide could take place when Mg containing alloys are heat-treated. It is expected that for these alloys the (hydr)oxide fraction also depends on the pre-treatment and on the distribution of magnesium as compared to the aluminium hydroxides, with a direct impact on adhesive properties.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.2
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• pp.67-73
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• 2019

In this study, to optimize the production and utilization of biogas for organic waste resources, the precision monitoring of on-site facilities and the energy balance by facility were analyzed, and the solutions for field problems were investigated, and the design and operation guidelines for pretreatment facilities and generators were presented. Gas pre-treatment is required to solve frequent failures and efficiency degradation in operation of high quality refining facilities, and processing processes such as desulfurization, dehumidification, deoxidization, dust treatment, volatile organic compounds, etc. Since these processes are substances that are also eliminated from the high-quality process, quantitative guidelines are not presented in the gas pretreatment process, but are suggested to operate during the processing process as a qualitative guideline. In particular, dust, siloxane, and volatile organic compounds are the main cause of frequent failure of high-quality processes if they are not removed from the gas pretreatment process. Design of the biogas high-quality process. The operation guidelines provide quality standards [Methane content (including propane) of 95% or more] with 90% or more utilization of the total gas generation, two systems, and a margin of 10% or more. It also proposed installing gas equalization tank, installing thermal automatic control system for controlling equalization of auxiliary fuel, installing dehumidification device at the back of high quality for removing moisture generated in the process of gas compression, installing heat-resisting facilities to prevent freezing of facilities in winter and reducing efficiency, and installing membrane facilities in particular.

• Korean Journal of Agricultural Science
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• v.20 no.2
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• pp.153-166
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• 1993

The experiments were conducted to improve raw milk quality during storage, the chemical composition and microbiological aspect of raw milk, milk thermized at $65^{\circ}C$ for 30 second, and $75^{\circ}C$ for 2 second stored at $5^{\circ}C$ for 4 days were investigated. The result obtained were summarized as follows : 1. During storage of raw and thermized milk, in the composition of milk fat, milk protein, lactose and total solid did not change significantly. 2. The range of pH and acidity for the raw milk were 6.73~5.94 and 0.16~0.27% respectively and those of the thermized milk were 6.79~6.62 and 0.16~0.17% respectively. The phosphatase test were negative in heated milk. 3. The composition of total nitrogen, NCN and whey protein were decreased, wherease those of NPN and casein were increased in heat treated milk. 4. The compositions of total nitrogen and casein were decreased as the storage period advanced, wherese those of NCN and NPN were increased. However, the composition of whey protein did not significantly change. 5. The number of coliform bacteria was not found in thermized milk. but were gradually increased in raw milk during storage period. 6. Raw milk had total bacteria count as $5.6{\times}10^6/ml$, psychrotrophic bacteria $1.8{\times}10^6/ml$ and thermoduric bacteria $1.6{\times}10^5/ml$, as the heat treatment increased microorganism counts decreased to milk thermized at $75^{\circ}C$, for 2 sec. $3.0{\times}10^3/ml$, $1.5{\times}10/ml$ and $2.7{\times}10^3/ml$ respectively. 7. The count of thermoduric bacteria, psychrotrophic bacteria and total bacteria were increased during storage period, and more rapidly increased in raw milk than in heat treated milk.

• Journal of Plant Biotechnology
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• v.41 no.3
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• pp.116-122
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• 2014

Total of fifty accessions of Brassica rapa with various morphological characteristics were used for production of double haploid plants though microspore culture in Brassica rapa. Among them, only 30 accessions induced embryos from microspores. The highest efficiency of embryo induction of 1.194 per bud was obtained from IT135449 of turnip type, while 3 accessions of sarson (winter oil) type did not generate embryo. The effect of heat shock periods for embryogenesis was also investigated with 4 accessions (IT135449; Turnip type, IT199710; Chinese cabbage type, IT212886; Pak choi type, IT218043; Summer oil type). The high productions of embryos were observed in IT135449, IT199710 and IT212886 when microspores were pre-cultured to $32^{\circ}C$ for 2 days. In IT218043, high embryogenesis was observed at the 3 days of heat shock treatment. The optimal condition of shoot regeneration for IT199710 was observed in MS medium supplemented with NAA $0.5mg{\cdot}L^{-1}$ and BAP $1mg{\cdot}L^{-1}$. In contrast, the IT135449 and IT212886 were observed high regeneration frequency in MS medium without plant growth regulators. All the plantlets regenerated from microspore-derived embryos have been successfully transplanted to soil, and bud self-pollinated seeds were produced from doubled haploid plants. This indicated that double-haploid genotype was likely generated naturally during embryogenesis process.

• Journal of Hydrogen and New Energy
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• v.17 no.4
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• pp.379-388
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• 2006

Two mesophilic trickling bed bioreactors filled with two different types of media, hydrophilic- and hydrophobic-cubes, were designed and conducted for hydrogen production under the anaerobic fermentation of sucrose. Each bioreactor consisted of the column packed with polymeric cubes and inoculated with heat-treated sludge obtained from anaerobic digestion tank. A defined medium containing sucrose was fed by the different hydraulic retention time(HRT), and recycle rate. Hydrogen concentrations in gas-phase were constant, averaging 40% of biogas throughout the operation. Hydrogen production rate was increased till $10.5\;L{\cdot}h^{-1}{\cdot}L^{-1}$ of bioreactor when influent sucrose concentrations and recycle rates were varied. At the same time, the hydrogen production rate with hydrophobic media application was higher than its hydrophilic media application. No methane was detected when the reactor was under a normal operation. The major fermentation by-products in the liquid effluent of the both trickling biofilters were acetate, butyrate and lactate. In order to run in the long term operation of both reactor filled with hydrophilic and hydrophobic media, biofilm accumulation on hydrophilic media and biogas produced should be controlled through some process such as periodical backwashing or gas-purging. Four sample were collected from each reactor on the opposite hydrogen production rate, and their bacterial communities were compared by terminal restriction fragment length polymorphism (T-RFLP) analysis of PCR products generated using bacterial 16s rRNA gene primers (8f and 926r). It was expressed a marked difference in bacterial communities of both reactors. The trickling bed bioreactor with hydrophobic media demonstrates the feasibility of the process to produce hydrogen gas. A likely application of this reactor technology can be hydrogen gas recovery from pre-treatment of high carbohydrate-containing wastewaters.

• Journal of the Korean Society of Marine Environment & Safety
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• v.11 no.2 s.23
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• pp.109-115
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• 2005

Hydrocyclone has been widely used for the solid-liquid separation in many industrial sites because of its comparatively preferable applications that can be applied to wide-range particle sizes. If seawater with impurities flows through pumps or heat exchanger, it might cause an decrease in the efficiency of cooling system In this paper, we have suggested some methods of separating impurities from seawater in the cooling system by using a Hydrocyclone. The effects of design factors as solid concentration, cyclone inlet pressure, flow rate and diameter of underflow on the separating performance of the Hydrocyclone were investigated The results from this study are summarized as follows: 1) In proportion to the decrease of solid concentration, the efficiency of solid-liquid separation is improved. 2) According as the cyclone inlet pressure increases the efficiency of separation is improved. Conclusively, this research suggested that the Hydrocyclone will be used as a pre-treatment system of cooling water in machines, and eventually prevent unexpected accidents in engine systems.

• Proceedings of KOSOMES biannual meeting
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• 2004.11a
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• pp.109-115
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• 2004

Hydrocyclone has been widely used for the solid-liquid separation in many industrial sites because of its comparatively preferable applications that can be applied to wide-range particle sizes. If seawater with impurities flows through pumps or heat exchanger, it might cause an decrease in efficiency of cooling system. In this paper, we have suggested some methods of separating impurities from seawater in the cooling system by using a Hydrocyclone. The effects of design factors as solid concentration, cyclone inlet pressure, flow rate and diameter of underflow on the separating performance of the Hydrocyclone were investigated The results from this study are summarized as follows: 1) In proportion to the decrease of solid concentration, the efficiency of solid-liquid separation is improved 2) According as the cyclone inlet pressure increases the efficiency of separation is improved Conclusively, this research suggested that the Hydrocyclone will be used as a pre-treatment system of cooling water in machines, and eventually prevent unexpected accidents in engine systems.

• Journal of the Microelectronics and Packaging Society
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• v.30 no.4
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• pp.98-104
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• 2023

The feasibility of an efficient process proposed for Cu-Cu flip-chip bonding was evaluated by forming a porous Cu layer on Cu pillar and conducting thermo-compression sinter-bonding after the infiltration of a reducing agent. The porous Cu layers on Cu pillars were manufactured through a three-step process of Zn plating-heat treatment-Zn selective etching. The average thickness of the formed porous Cu layer was approximately 2.3 ㎛. The flip-chip bonding was accomplished after infiltrating reducing solvent into porous Cu layer and pre-heating, and the layers were finally conducted into sintered joints through thermo-compression. With reduction behavior of Cu oxides and suppression of additional oxidation by the solvent, the porous Cu layer densified to thickness of approximately 1.1 ㎛ during the thermo-compression, and the Cu-Cu flip-chip bonding was eventually completed. As a result, a shear strength of approximately 11.2 MPa could be achieved after the bonding for 5 min under a pressure of 10 MPa at 300 ℃ in air. Because that was a result of partial bonding by only about 50% of the pillars, it was anticipated that a shear strength of 20 MPa or more could easily be obtained if all the pillars were induced to bond through process optimization.