• Journal of Soil and Groundwater Environment
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• v.29 no.2
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• pp.1-10
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• 2024

With industrial development, the inevitable increase in both organic and inorganic waste necessitates the exploration of waste treatment and utilization methods. This study focuses on co-pyrolyzing lignin and red mud to generate metalbiochar, aiming to demonstrate their potential as effective adsorbents for water pollutant removal. Thermogravimetric analysis revealed mass loss of lignin below 660℃, with additional mass loss occurring (>660℃) due to the phase change of metals (i.e., Fe) in red mud. Characterization of the metal-biochar indicated porous structure embedded with zero-valent iron/magnetite and specific functional groups. The adsorption experiments with 2,4-dichlorophenol and Cd(II) revealed the removal efficiency of the two pollutants reached its maximum at the initial pH of 2.8. These findings suggest that copyrolysis of lignin and red mud can transform waste into valuable materials, serving as effective adsorbents for diverse water pollutants.

• Journal of Radiation Protection and Research
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• v.28 no.1
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• pp.25-33
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• 2003

The automatic system for $^{67}Ga$ production using for the diagnosis of malignant tumor has been developed. A solvent extraction and an ion exchange chromatography were used for the separation $^{67}Ga$ from the irradiated enriched $^{68}Zn$. This system consisted of a solvent separation unit which was composed of micro conductivity cells, air supply tubes, solvent transfer tubes, solenoid valves and glasses, a PLC based controller and a PMU user interface unit for automation. The radiation exposure to the workers and the production time can both be reduced by employing this system during the $^{67}Ga$ production phase. After all, the mass production of $^{67}Ga$ with high efficiency was possible.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.5
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• pp.705-711
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• 2018

Objective: This experiment was conducted to evaluate the effects of golden needle mushroom (Flammulina velutipes) stem waste (FVW), on organic eggs production, calcium utilization, antibody response, serum immunoglobulin, and serum cytokine concentration at early phase of production in laying hens. Methods: A total 210, 19 weeks old aged ISA Brown layers were randomly assigned into 5 equal treatment groups, with 7 replications of 6 hens each. Dietary treatment included a standard basal diet as control; antibiotic (0.05% flavomycin); 2% FVW; 4% FVW; and 6% FVW. The experimental duration was 10 weeks. Results: There was no significant differences (p>0.05) on hen day egg production, egg weight, egg mass, feed intake, and feed conversion ratio (FCR) among experimental groups. Unmarketable eggs were significantly lower (p<0.05) both in 4% FVW and 6% FVW fed groups than control group. The calcium retention and calcium in egg shell deposition were significantly higher (p<0.05) in FVW inclusion groups than control and antibiotic groups. Antibody titers against Newcastle diseases were significantly higher (p<0.05) in 6% FVW fed group (except combined with 4% FVW at day 147) and infectious bronchitis were significantly higher (p<0.05) in FVW fed groups (except 2% FVW and 4% FVW at day 161) than control and antibiotic groups. Serum immunoglobulin sIgA was significantly higher (p<0.05) in all levels of FVW and IgG was significantly higher (p<0.05) in 4% FVW than control and antibiotic groups. Serum cytokine concentration interleukin-2 (IL-2) was significantly higher (p<0.05) in 6% FVW; IL-6 and tumor necrotic $factor-{\alpha}$ were significantly higher (p<0.05) both in 4% FVW and 6% FVW than control and antibiotic groups; IL-4 was significantly higher (p<0.05) in antibiotic, 2% FVW and 4% FVW fed groups than control. Conclusion: F. velutipes mushroom waste can be used as a novel substitute for antibiotic for organic egg production and sound health status in laying hens.

• Journal of Microbiology and Biotechnology
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• v.12 no.1
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• pp.14-17
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• 2002

To increase the efficiency of a two-stage anaerobic wastewater digestion system, various polymers were added to the methanogenic reactor as supports. The addition of polyurethane addition (6%, w/v) to the methanogenic reactor facilitated the organic loading rate (2-day Hydraulic Retention Time), higher than that of the conventional methanogenic reactor (6-day HRT). During the operation of the polyurethane-added reactor, a significant decrease in the organic mass in the effluent (COD 5-6 kg/l) was achieved, compared to that of the conventional reactor (COD 15-20 kg/l). The methane gas production rate also improved about 3-fold in the polyurethane-added reactor. More biomass was found to accumulate in the polyurethane-liquid phase (volatile solid, 26-28kg) than in the free-liquid phase (volatile solid, 5- 7 kg/l) after 90 days of operation. A scaled-up experiment with a polyurethane-added 2.5-1 reactor confirmed the previous results, and no adverse effects such as plugging or channeling due to decreased efficiency was observed even after 4 months of operation.

• Mycobiology
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• v.41 no.3
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• pp.149-154
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• 2013

An ${\alpha}$-glucosidase inhibitor was developed from Aspergillus oryzae N159-1, which was screened from traditional fermented Korean foods. The intracellular concentration of the inhibitor reached its highest level when the fungus was cultured in tryptic soy broth medium at $27^{\circ}C$ for five days. The inhibitor was purified using a series of purification steps involving ultrafiltration, Sephadex G-25 gel permeation chromatography, strong cation exchange solid phase extraction, reverse-phase high performance liquid chromatography, and size exclusion chromatography. The final yield of the purification was 1.9%. Results of the liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis indicated that the purified ${\alpha}$-glucosidase inhibitor was a tri-peptide, Pro-Phe-Pro, with the molecular weight of 360.1 Da. The IC50 value of the peptide against ${\alpha}$-glucosidase activity was 3.1 mg/mL. Using Lineweaver-Burk plot analysis, the inhibition pattern indicated that the inhibitor acts as a mixed type inhibitor.

• Journal of the Korean Ceramic Society
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• v.50 no.6
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• pp.533-538
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• 2013

Silicon carbide (SiC) materials are typical ceramic materials with a wide range of uses due to their high hardness and strength and oxidation resistance. In particular, due to the corrosion resistance of the material against acids and bases including the chemical resistance against ionic gases such as plasma, the application of SiC has been expanded to extreme environments. In the SiC deposition process, where chemical vapor deposition (CVD) technology is used, the reactions between the raw gases containing Si and C sources occur from gas phase to solid phases; thus, the merit of the CVD technology is that it can provide high purity SiC in relatively low temperatures in comparison with other fabrication methods. However, the product yield rarely reaches 50% due to the difficulty in performing uniform and dense deposition. In this study, using a computational fluid dynamics (CFD) simulation, the gas velocity inside the reactor and the concentration change in the gas phase during the SiC CVD manufacturing process are calculated with respect to the gas velocity and rotational speed of the stage where the deposition articles are located.

• Journal of Sensor Science and Technology
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• v.31 no.4
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• pp.228-237
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• 2022

Two-dimensional (2D) nanomaterials have demonstrated the potential to replace silicon and compound semiconductors that are conventionally used in photodetectors. These materials are ultrathin and have superior electrical and optoelectronic properties as well as mechanical flexibility. Consequently, they are particularly advantageous for fabricating high-performance photodetectors that can be used for wearable device applications and Internet of Things technology. Although prototype photodetectors based on single microflakes of 2D materials have demonstrated excellent photoresponsivity across the entire optical spectrum, their practical applications are limited due to the difficulties in scaling up the synthesis process while maintaining the optoelectronic performance. In this review, we discuss facile methods to mass-produce 2D material-based photodetectors based on the exfoliation of van der Waals crystals into nanosheet dispersions. We first introduce the liquid-phase exfoliation process, which has been widely investigated for the scalable fabrication of photodetectors. Solution processing techniques to assemble 2D nanosheets into thin films and the optoelectronic performance of the fabricated devices are also presented. We conclude by discussing the limitations associated with liquid-phase exfoliation and the recent advances made due to the development of the electrochemical exfoliation process with molecular intercalants.

• Journal of the Korea Furniture Society
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• v.17 no.4
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• pp.1-13
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• 2006

This study attempted to identify the characteristics of chair design from furniture company, $K{\ddot{a}}llemo$, the furniture manufacturer in Sweden manufacturing mostly the limited edition of art furniture on the basis of the unique management philosophy. There are 12 artists manufactured chairs for $K{\ddot{a}}llemo$. Of them, this study selected 4 artists-Sigurdur Gustafsson, John Kandell, Komplot Design, Mats Theselius-who designed at least more than three chairs. Total 25 chairs were analyzed; 6 from Sigurdur Gustafsson, 8 from John Kandell, 3 from Komplot Design and 8 from Mats Theselius. The chair structure was divided into three parts, seat, back and structure and analyzed by material, color, type of legs and finishing. The following results were derived from the study. First, $K{\ddot{a}}llemo$ secured the regular customers who want to possess the chairs as the artistic works by continuing the small quantity mass-production system insisting that the maximum quantity of production is 360 pieces and the minimum quantity is 33 pieces. Second, the sufficient time and cost were invested in the initial phase of design. This approach seems to be deviated from the traditional business system that has to create the revenue at a glance, but ultimately induces the commercial success by exponentially increasing the revenue through the creation of various product lines. Third, $K{\ddot{a}}llemo$ provides the space that the artists who work for $K{\ddot{a}}llemo$ can sufficiently enjoy the mental composure and luxury required for the designers by strictly selecting the artists and providing the best environment for enabling the creative activities that look like the pure art area. This study enables the further analysis and research on other collections of $K{\ddot{a}}llemo$ that mass-produces the chairs on the basis of the unique philosophy in the world as well as in Sweden using more various kinds of analysis frameworks.

• Journal of Microbiology
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• v.40 no.1
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• pp.20-25
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• 2002

An extracellular PHB depolymerase was purified from P. simplicissimum LAR13 cultural medium by Sepharose CL-6B chromatography. When the fungus was grown in a basal salt medium with poly(3-hydroxybutyrate) (PHB) as the sole carbon source, PHB depolymerase production reached maximum at its stationary phase. The mycelial growth rate was higher at 37$^{\circ}C$ than at 30$^{\circ}C$ and even higher than at 25$^{\circ}C$, However, the enzyme production was lower at 37$^{\circ}C$ than 30$^{\circ}C$ or 25$^{\circ}C$. The isolated enzyme is composed of a single polypeptide chain with a molecular mass of about 36 kDa as determined by SDS-PAGE. The optimum conditions for the enzyme activity are pH 5.0 and 45$^{\circ}C$. The enzyme was stable for 30 min at a temperature lower than 50$^{\circ}C$, and stable at pH higher than 2.0 but it was unstable at pH 1.0.1 mM Fe$\^$2+/ reduced the enzyme activity by 56% and the enzyme was inhibited almost completely by 4 mM Fe$\^$2+/ . The enzyme was partially inhibited by phenylmethylsulfonyl fluoride and was very sensitive to diazo-DL-norleucine methyl esters dithiothreitol and mercuric ion. However, N-p - tosyl - L - Iysinechloromethyl ketone, p -hydroxymercuricbenzoate and N- acetylimidazole had no influence upon its activity.

• Journal of the Korea Society for Simulation
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• v.12 no.3
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• pp.41-53
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• 2003

The major components of an engine are engine block (or cylinder block), cylinder head, crank shaft, connecting rod and cam shaft. Thus the engine shop usually consists of six sub-lines, five machining lines and one assembly line. Flow line is the typical concept of layout for machining these parts, especially for engine block. In order to design an engine block machining line, several factors should be considered such as yearly production target, working hours, machines, tools, material handling equipments and so on. If the designers of manufacturing line were unaware of some factors those would be influenced on the system performance, it would make greater problems in the phase of mass production. Therefore the initial design of engine block machining line should be verified carefully. Simulation is the most powerful tool for analyzing the initial layout. This paper introduces the major factors those should be considered for designing the machining line and their effects on the system performance. 3D simulation models are developed with QUEST. Using the simulation model developed the initial layout is analyzed, and we suggest some ideas for improvement.