• Transactions of the Korean hydrogen and new energy society
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• v.27 no.5
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• pp.612-619
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• 2016

Pitch synthesis reaction was studied based on the effect for chemical composition of feedstock. Feedstock was selected as pyrolyzed fuel oil (PFO) and coal-tar (CT), which are by-products in petroleum and steel industry. Pitch was prepared at $420^{\circ}C$ for 180 minutes on atmospheric pressure by thermal treatment. Thermal stability and softening point (SP) of the prepared pitches were investigated and their molecular weight distribution was analyzed by MALDI-TOF. PFO has various aliphatic compounds and coal-tar has high aromaticity with 3 wt% of primary quinoline insolubles. The thermal property of PFO was enhanced with polymerization reaction during the thermal treatment with increased molecular weight range. But CT was inferior to PFO because of side reaction by hetero elements. CTP was appeared molecular weight by 0~200 m/z.

• Nano
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• v.13 no.12
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• pp.1850138.1-1850138.6
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• 2018

Two-dimensional (2D) or layered materials have a great potential for applications in energy storage, catalysis, optoelectronics and gas separation. Fabricating novel 2D or quasi-2D layered materials composed of relatively abundant and inexpensive atomic species is an important issue for practical usage in industry. Here, we suggest the layer-structured AlOOH (Boehmite) as a promising candidate for such applications. Boehmite is a well-known layer-structured material and a single-layer can be exfoliated from the bulk boehmite by breaking the interlayer hydrogen bonding. We study atomic and electronic band structures of both bulk and single-layer boehmite, and also obtain the single-layer exfoliation energy using first-principles calculations.

• Transactions of the Korean hydrogen and new energy society
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• v.31 no.6
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• pp.499-508
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• 2020

Whilst vehicle-to-every (V2X) is still at a research and development phase, we are nearing the point when this technology could begin to enter in commercial mass markets. However, this transition is unlikely to happen until a number of issues have been resolved which currently hinder the developing of V2X technology and its capacity to provide value to end-users and other actors. This roadmap has set out plan for how these issues may be overcome, based on eight key goals that the automotive industry, network operators and policy makers should aim to achieve. Suggestions for near-term activities that may be carried out towards meeting these goals have also been identified.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.2
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• pp.83-90
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• 2016

Increasing the amount of filler in paper is of high interest for paper industry while maintaining its key sheet quality properties. In this study, a MFC-GCC composite, made through a co-grinding NBSK (Northern bleached softwood kraft) pulp with a ground calcium carbonate (Intracarb 60), was used as a strength aid in paper in order to evaluate a potential cost reduction through filler increase without sacrificing paper quality. Hand-sheets were made of NBSK and/or eucalyptus pulp by using white water recirculation in a Tappi sheet former and was compared its properties without or with MFC additions at different filler levels. It was found that the MFC-GCC composite has a large surface area compared to the fiber, allowing the formation of more hydrogen bonds in the web, thus giving natural strength to the paper. Overall results are encouraging that the MFC-GCC composite allows papermaker to reduce basis weight and maintain critical sheet properties.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.11
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• pp.1414-1419
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• 2019

Patent indicators were used to analyze the movements of local industries in order to derive blank technologies due to rapid changes in technology in the 4th Industrial Revolution and to discover promising technologies. Currently, Changwon-si is gathering a lot of technical information to develop hydrogen electric vehicle technology as a future regional flagship industry to discover it as a promising technology in the future. Collecting technical information has many problems in terms of time and cost due to classification methods, technical trends, and similar technologies. Therefore, a systematic classification of technical information and a method for easily deriving technical trends are needed. In this paper, we analyzed the blank technology and promising technology trends for the future core industries of the region through the method of measuring the growth rate of patents and the frequency of patent application through the patent indicators.

• Transactions of the Korean hydrogen and new energy society
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• v.25 no.5
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• pp.533-540
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• 2014

The remanufacturing industry for automotive parts is a major issue which affects the environment protection and CO2 reduction throughout the world. Beside this, remanufacturing technologies of worn-out diesel engines have been developing to make as close to new as possible. In this study, the characteristics of the engine-power output and exhaust emissions of remanufactured diesel engine by hydrogen enrichment are evaluated by measuring the engine and vehicle test. Moreover, with worn-out diesel engine and first generation common-rail engine, we compared by testing their characteristics, resulting in the restoration of engine-power output more than 93%, as well as marvelously reduces the THC and NOx emission. At a guess, high pressure injection of diesel increases fuel atomization characteristics with excellence combustion efficiency, resulting in reduction of THC emission. Also, rapid cooling of EGR decreases combustion temperature, resulting in reduction of NOx emission. Consequently, these remanufacturing for diesel engine enables worn-out diesel engine to have restoration to the original state. Simultaneously achieved 2 goals called that CO2 emission reduction and protection of environment by remanufacturing engine.

• Journal of the Korean Society for Heat Treatment
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• v.24 no.1
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• pp.31-36
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• 2011

$TiO_2$ films were deposited on a glass substrate with RF magnetron sputtering and then surface of $TiO_2$ films were electron beam irradiated in a vacuum condition to investigate the effect of electron bombardment on the thin film crystallization, surface roughness and gas sensitivity for hydrogen. $TiO_2$ films that electron beam irradiated at 450eV were amorphous phase, while the films irradiated at 900 eV show the anatase (101) diffraction peak in XRD pattern. AFM measurements show that the roughness is depend on the electron irradiation energy. As increase the hydrogen gas concentration and operation temperature, the gas sensitivity of $TiO_2$ and $TiO_2$/ZnO films is increased proportionally and $TiO_2$ films that electron beam irradiated at 900 eV show the higher sensitivity than the films were irradiated at 450eV. From the XRD pattern and AFM observation, it is supposed that the crystallization and rough surface promote the hydrogen gas sensitivity of $TiO_2$ films.

• Applied Chemistry for Engineering
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• v.25 no.3
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• pp.324-329
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• 2014

Microalgae Nannochloropsis oculata (N. oculta) and Chlorella vulgaris (C. vulgaris) are important sources for biodisel because of the high content of neutral lipids. Stable nano bubble is maintained for a long time and therefore it is possible for use in biotechnology. In this study, effects of nano bubble oxygen or hydrogen water on the microalgae growth were characterized. The cell growth in nano bubble water was similar to that of control, and the total lipid content was rather low. But, chlorophyll content of N. oculata grown in nanno bubble oxygen and hydrogen water increased 54% and 30%, and increased 59%, 39% in C. vulgaris. Carotenoid content also increased 21%, 25% in N. oculata and 49%, 29% in C. vulgaris grown in nano bubble oxygen and hydrogen water. From these results, nano bubble water seems to enhance the photosynthetic capacity of microalgae.

• Korean Journal of Remote Sensing
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• v.37 no.3
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• pp.591-601
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• 2021

As the domestic chemical industry continues to develop, handling and transportation of chemicals increases every year. Road freight in Korea accounts for more than 90%, and most of the chemical transportation is done through roads. These chemical vehicles can lead to major accidents if accidents occur. Transportation vehicles are likely to cause water pollution and soil pollution, which are factors of environmental damage, as well as traffic accidents that are the primary damage. In this work, we write a scenario for hydrogen chloride gas leakage by setting Banpo IC and Seocho IC sections as research areas, and use the ALOHA program to measure the predicted distance and analyze the time when hydrogen chloride gas reached according to the distance. In addition, risk assessment using population density was carried out for areas of damage caused by time using GIS. This suggests the need for prevention and countermeasures in areas of damage.

• Food Science and Preservation
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• v.16 no.6
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• pp.915-923
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• 2009

For preparation of high-quality salted mackerel using enzymatic extracts from Ecklonia cava (EEC) to process fresh mackerel caught off Jeju Island, the optimal concentration of EEC was investigated. There were no differences in proximate composition, salinity, Escherichia coli level, pH, volatile basic nitrogen content, histamine level, or peroxide value between salted mackerel samples prepared with different concentrations of EEC. However, the antiradical properties of salted mackerel, assayed by scavenging of DPPH free radicals, hydroxyl radicals, hydrogen peroxide, and alkyl radicals, increased with increasing concentrations of EEC. The optimal concentration of EEC for preparation of high-quality salted mackerel was 2% (w/w). Salted mackerel soaked in 2% (w/w) EEC was superior to commercial salted mackerel in antiradical properties, biogenic amine content, and other relevant chemical properties.