• Economic and Environmental Geology
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• v.39 no.6 s.181
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• pp.753-770
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• 2006

In urban areas, groundwater pollution is heavily affected by urbanization with land use types. This study aims to characterize groundwater quality and contamination in Sasang industrial area of Busan Metropolitan City where metalworking, machinery and footwear factories are located. Busan Metropolitan City is the highest in the utilization of groundwater resources among the metropolitan cities in Korea. $K^+,\;Na^+,\;Ca^{2+},\;Mg^{2+},\;Cl^-,\;SO_4^{2-}\;and\;HCO_3^-$ concentrations, and electrical conductivity (EC), total dissolved solids (TDS) and salinity are high in the areas near the Nakdong River. The results are attributed to the influence of salt water which intruded into the coastal sediments during sedimentation. In addition, the dominant chemical type of Ca-Cl indicates the influence of salt water in the geological formations as well as anthropogenic pollution. $SiO_2$ ion is interpreted to originate from both water-silicate mineral reactions and the decomposition of cement concretes. Trichloroethylene (TCE) was detected at 12 sites of total 18 sites. However, tetrachloroethylene (PCE) was detected at f sites and 1.1.1-trichloroethane (TCA) at 3 sites. According to the factor analysis, factor 1 was explained by 49.8%, factor 2 19.8%, and factor 3 11.0% with total 80.6% explanation. pH, TDS, salinity, $Ca^{2+},\;K^+,\;Mg^{2+},\;Na^+,\;Al^{3+},\;As^{3+},\;Cl^-\;and\;Fe^{2+}$ were positively highly loaded to factor 1. The chemical components loaded to factor 1 represent the chemical characteristics of both industrial pollution and influence by salt water. Based on the cluster analysis and distribution pattern of chemical components, the concentration of $Na^+,\;Ca^{2+},\;Cl^-,\;SO_4^{2-}\;K^+,\;and\;Mg^{2+}$ is high in the riverside area of the Nakdong River composed of coastal sediments that is influenced by salt water. The downstream area of the Hakjang Stream is judged to be affected by both salt water and artificial pollution. The other part of the study area is interpreted by anthropogenic pollution.

• Food Science of Animal Resources
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• v.38 no.4
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• pp.679-692
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• 2018

The effects of high-pressure processing (HPP) treatment on the quality characteristics of low graded Hanwoo beef marinated with five different sauces (soy, fish, fish-soy, soy-fish and fish-soy-meat sauces) obtained from Asian countries were studied. The Hanwoo beef striploins were marinated with the aforementioned sauces (at ratio: 3:1 w/w) for 3 days at $4^{\circ}C$ before they were treated with HPP at 550 MPa for 5 min at $10^{\circ}C$. All the sauces used were equalized to a same salt level of 12.5%, and the samples marinated with a 12.5% brine solution were served as a control. After treating with the HPP, all the samples were stored for further 7 days at $4^{\circ}C$ for analyses. Results revealed that HPP treatments showed some effects on technological quality traits (pH, cooking loss and color) but had no effect on the collagen contents of the marinated beef. Noticeably, the HPP treatment led to the increases in amounts of free amino acids associated with monosodium glutamate-like taste and sweet taste in the samples marinated with fish sauce or soy-fish sauce, fish-soy sauce and fish-soy-meat sauce whereas, it only reduced these amino acids in the samples marinated with soy sauce or control. Furthermore, the total bacteria count in all the marinated beef samples treated with HPP were significantly (p<0.05) lower than those of the non-HPP-treated samples throughout the storage periods. It is concluded that HPP could be applied for enhancing the taste-active compounds production such as free amino acids, and improving the shelflife stability of the marinated beef.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.447-450
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• 2000

Recently, antiwashout underwater concrete has used for underwater structure such as high strength massive concrete structures. When, concrete is placed in seawater the quality and durability of concrete could be doubt to especcially because the amount of cement placed in the concrete can be diminished by flowing seawater. In this study, antiwashout underwater concrete mixed with mineral admixtures for improvement of properties was placed in air, water, and salt water. Half-cell potential and current density was of specimens which made under different conditions measured for estimating corrosion degree. The experimental results demostrate that corrosion resistantce in saltwater was little and mineral admixtures improved properties of concrete.

• Journal of the Korean Society of Food Science and Nutrition
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• v.1 no.1
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• pp.51-62
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• 1972

In Korea, fermented fish has been playing an important role as a preserved and flavor rich food. It is said that the digestion of fish protein is due to both action of intrinsic (autolytic enzymes) and bacterial enzymes in fish. The mass production of fermented fish has been impeded since traditional method of fermentation requires a long duration for a complete digestion. A high concentration of salt and unsanitary condition are also considered disadvantages of the old method. To improve the quality of the product and to develop mechanized process of fermentation, fermentors which have such control device as temperature, pH and agitation control system have been urgently needed. In this study, a model design of a fermentor is studied. The calculation was based on the optimum conditions for enzymatic hydrolysis of fish protein which involve temperature, pH, viscosity and other factors.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2007.04a
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• pp.147-150
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• 2007

As recent buildings often use low-quality concrete materials, are constructed defectively, and are put in extreme environmental conditions, many of them show the shortening of life resulting from the corrosion of reinforcing rods by salt damage, carbonization, freezing and thawing, cracking. This in turn raises the cost of repair and maintenance, so it is required to extend the life of structures through enhancing the durability of concrete. In response to the demand, researches on high-durability concrete are being made actively focused on the maximum water-cement ratio, the maximum unit quantity, the minimum cover thickness, the addition of mineral admixtures, etc. With this background, the present study examined the basic physical properties of concrete containing admixtures for enhancing the durability of concrete.

• Bulletin of the Korean Chemical Society
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• v.35 no.2
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• pp.521-524
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• 2014

Pyronaridine tetraphosphate (1) is a well-known antimalarial drug. However, it required a carefully optimized production process for the manufacture of pyronaridine tetraphosphate. Each step of its manufacturing process was reinvestigated. For the cyclization of 4-chloro-2-(6-methoxy-pyridin-3-yl-amino)-benzoic acid 6 to 7,10-dichloro-2-methoxybenzo[b]-1,5-naphthyridine 5, an improved process was developed to eliminated critical process impurity (BIA). By the redesign of the formation of triphosphate salt, the purity as API grade was increased. Thus, a robust manufacturing process with an acceptable process performance has been developed to produce high quality pyronaridine tetraphosphate.

• Journal of the Korea Furniture Society
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• v.19 no.4
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• pp.229-234
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• 2008

In a previous study, it was revealed that three major softwoods, Japanese pine, Korean pine and Japanese larch, heat-treated at $220^{\circ}C$, could produce high quality dark-colored boards. It is known that heat treatment decreases the hygroscopicity of wood. The hygroscopicity of major domestic softwoods and hardwoods heat-treated at $220^{\circ}C$ was investigated by a saturated salt solution method and compared with that of black and white charcoals. Equilibrium moisture contents of wood decreased with the increase of heat treatment time. Isotherm shapes of wood species were different from those of charcoals. Heat treatment decreases the equilibrium moisture contents of black locust more than those of Korean pine and Japanese larch. It was found that surface hardness of wood is improved by heat treatment to a certain extent, but a longer heat treatment causes thermal degradation, resulting in the decrease of the surface hardness.

• Journal of Ceramic Processing Research
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• v.19 no.6
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• pp.499-503
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• 2018

In this paper, cobalt embedded in nitrogen and sulfur co-doped carbon nanotubes (CoNSTs) were synthesized for oxygen reduction reaction (ORR) catalysts. The CoNSTs were prepared through a facile heat treatment method without any templates. Different amounts of the metal salt were employed to examine the physicochemical and electrochemical properties of the CoNSTs. The CoNSTs showed the bamboo-like tube morphology with the encased Co nanoparticles in the tubes. Through the x-ray photoelectron spectroscopy analysis, the catalysts exhibited different chemical states of the nitrogen and sulfur species. As a result, the CoNST performed high activity toward the ORR in an acidic condition with the onset potential of 0.863 V (vs. reversible hydrogen electrode). It was clearly demonstrated from the electrochemical characterizations that the quality of the nitrogen and sulfur species significantly influences the ORR activity rather than the total amount of the dopants.

• Journal of Adhesion and Interface
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• v.22 no.3
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• pp.111-111
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• 2021

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.5
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• pp.437-441
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• 2003

This research investigated the effects of processing conditions and natural antimicrobial materials on quality of freeze-dried, seasoned and roasted Alaska pollack (Theragra chalcogramma). The optimum dipping time and moisture contents of freeze-dried Alaska pollack were 1 sec in $1\%$ salt solution, $48.6\%$ respectively. The freeze-dried, seasoned and roasted Alaska pollack product showed high sensory value. As sterilization time increased over 30 mins in water bath at $100^{\circ}C$ the browning degree of the freeze-dried, seasoned and roasted Alaska pollack product increased. Among various antibrowning agents, $3\%$ corn starch was better in preventing browning than sporix treatment. The freeze-dried, seasoned and roasted Alaska pollack product added with lactate Ca and catechin had the antimicrobial, and the VBN contents of the product showed low level.