• Korean Journal of Materials Research
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• v.26 no.6
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• pp.332-336
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• 2016

Three kinds of porous polymer were synthesized using a solvothermal of tri-4,4'-diphenylmethane diisocyanate (MDI-trimer) and different diamino monomers. The effects of the synthesis conditions and the monomer selection on the synthesis of porous polymer properties were studied. The results show that the synthesis of $NH_2$-containing monomer molecules smaller the microporous polymers was easy to implement; the specific surface areas of the polymers are related to the monomer ratio and the reaction time. The results show that the synthesized porous polymer had good hydrogen storage performance; the hydrogen storage ability improved with the addition of heterocyclic nitrogen.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.21 no.2
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• pp.55-60
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• 2015

Packaging of export cut lilies reduces physical damage during distribution like dropping, shock, vibration, compression and serves to protect from necrosis, microbial contamination and decomposition. Study on which packaging materials must be selected is necessary because it serves to direct effect maintaining quality and the degree of freshness. newspaper, perforated OPP film, Oriented Nylon film (ON), punched OPP film, OPP films are used in this study. Plant senescence of lilies was happened rapidly during storage at $25^{\circ}C$ rather than at $5^{\circ}C$. Also, water absorption, fresh weight at during storage $25^{\circ}C$ rather than at $5^{\circ}C$ In addition, fresh weight of lilies storage at $25^{\circ}C$ appears higher than at $5^{\circ}C$ all of the packaging materials except OPP because water absorption of lily storage at $5^{\circ}C$ appears higher than at $25^{\circ}C$, thereby suppressing the fresh weight reducing Also, effect on biological activity of lilies from shape of packaging material appears higher during storage at $5^{\circ}C$ than at $25^{\circ}C$. Compared with each packaging materials, newspaper packaging is the smallest effect on changes in biological activity of cut lilies during storage. Thus, the results demonstrate that flowering date are affected mainly by the storage temperature rather than packaging materials.

• Journal of Energy Engineering
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• v.20 no.3
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• pp.178-184
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• 2011

Compressed Air Energy Storage (CAES) is a combination of energy storage and generation by storing compressed air using off-peak power for generation at times of peak demand. In general, both charging and discharging of high-pressure vessel are unsteady processes, where the pressure is varying. These varying conditions result in low efficiencies of compression and expansion. In this paper, a new constant-pressure CAES system to overcome the current problem is proposed. An energy analysis of the system based on the concept of exergy was performed to evaluate the energy density and efficiency of the system in comparison with the conventional CAES system. The new constant-pressure CAES system combined with pumped hydro storage requires the smaller cavern with only half of the storage volume for variable-pressure CAES and has a higher efficiency of system.

• Transactions of the Korean hydrogen and new energy society
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• v.18 no.3
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• pp.250-255
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• 2007

Hydrogen storage properties of $Ti_{0.32}Cr_{0.43-X}V_{0.25}M_X$($0{\leq}X{\leq}0.1$, M=Fe, Mn, Si) have been investigated. With varing of Mn content, the lattice parameter of the alloy was unchanged and similar to that of $Ti_{0.32}Cr_{0.43}V_{0.25}$ alloy. With increase of Fe, Si content, the lattice parameters of the BCC phases decreased. When the Fe content was 8 at%, the desorption plateau pressure increased to several atmospheres without decrease of the effective hydrogen storage capacity of the alloy. When the Mn content was 8 at%, the effective hydrogen storage capacity showed approximately 2.5 wt% without change in the desorption plateau pressure. With increase of Si content, hysteresis increased and hydrogen storage capacity decreased rapidly. A study was also made on how desorption temperature affected the usable hydrogen of the $Ti_{0.32}Cr_{0.35}V_{0.25}Mn_{0.08}$ alloy. The temperature was varied from 293 to 413 K, and the pressure from 5 to 0.002 MPa. The usable hydrogen of the alloy was 2.7 wt% when absorbed and desorbed at 293 K and 373 K., respectively. The heat of hydride formation of the alloy was approximately -35.5 kJ/mol $H_2$.

• Korean journal of food and cookery science
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• v.32 no.4
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• pp.400-412
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• 2016

Purpose: This study was conducted to develop easy-made ssamjang products with differentiated materials and methods to meet the needs for a healthy and easy- lifestyle trend with lowered manufacturing expenses. Methods: Ssamjang was made with cheonggukjang and different kinds of jocheong as glutinous (GRSS), sweet potato (SPTSS), sweet pumpkin (SPKSS), bellflower root (BRSS) and ginger (GSS) and stored at $4^{\circ}C$ for 16 weeks. Quality characteristics and consumer acceptability were measured. Results: Titratable acidity was higher in SPTSS and rapidly increased (p<0.05) after 9 weeks in all groups during storage. Amino-type nitrogen contents of SPTSS and SPKSS were the highest and rapidly increased (p<0.05) after 5 weeks. Total free sugar content was higher in GRSS and did not change during storage. Glutamic acid and total free amino acid contents were higher in SPTSS, SPKSS and continuously increased up to 9 weeks. Yeast counts rapidly increased (p<0.05) after 9 weeks reaching 4.0 Log CFU/g in all groups except for SPTSS. Consumer acceptability did not change during storage in all groups and GSS was least preferable. Conclusion: The optimal quality maintenance period of ssamjang with cheonggukjang and jocheong was determined to 7-9 weeks of storage at $4^{\circ}C$ and ginger jocheong was the least preferable materials. We conclude that it is possible to develop easy-made ssamjang products with cheonggukjang and non-fermented materials also skipping aging period.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.3
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• pp.306-315
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• 2012

In this study, storage stability of reduced sulfur compounds ($H_2S$, $CH_3SH$, DMS, $CS_2$, and DMDS) and $SO_2$ in sampling bags was investigated in terms of two contrasting storage approaches between forward (F) and reverse (R) direction. The samples for the F method were prepared at the same time and analyzed sequentially through time. In contrast, those of reverse (R) method were prepared sequentially in advance and analyzed all at once upon the preparation of the last sample. In addition, relative performance between two different bag materials (PVF and PEA) was also assessed by using 100 ppb standard. The response factors (RF) of gaseous RSC samples were determined by gas chromatography/pulsed flame photometric detector (GC/PFPD) combined with air server (AS)/thermal desorber (TD) system at storage intervals of 0, 1, and 3 days. There is no statistical difference in all RSCs between two storage methods. However, the results of relative recovery indicated 2.58~12.8% differences in compound type between the two storage methods. Moreover, loss rates and storage stability of $H_2S$ and $SO_2$ were considerably affected by bag materials than any other variables. Therefore, some considerations about storage methods (or bag material types) for sulfur compounds are needed if stored by sampling bag method.

• Transactions of the Korean hydrogen and new energy society
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• v.13 no.2
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• pp.110-118
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• 2002

The hydrogen storage vessel having a good heat conductivity along with a simple structure and a low cost for these alloys was designed and manufactured, and then its characteristic properties were studied in this study. The various parts in hydrogen storage vessel consisted of copper pipes and stainless steel of 250 mesh reached the setting temperature after 4~5 minutes, which indicated that storage vessel had a good heat conductivity that was required in application. And also the storage vessel had a good property of hydrogen transport considering that the reaction time between hydrogen and rare-earth metal alloys in storage vessel was found to be within 10 min at $18^{\circ}C$ under 10 atmospheric pressure. It showed that the average capacity of discharged hydrogen volume was found to be $120{\ell}$ for $MmNi_{4.5}Mn_{0.5}$ under discharging conditions of $40^{\circ}C{\sim}80^{\circ}C$ at a constant flow rate of $5{\ell}$/min. It was found that the optimum discharging temperature for obtaining an appropriate pressure of 3atm was determined to be $60^{\circ}C$ for $MmNi_{4.5}Mn_{0.5}$ hydrogen storage alloy.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.190-193
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• 2008

The heat transfer characteristics of molten salt storage system for the solar thermal power generation were investigated. Temperature profiles and the heat transfer coefficients during the storage and discharge stage were obtained with the steam as the heat transfer fluid. Two kinds of inorganic salt were employed as the storage materials and coil type of heat exchanger were installed in both tanks to provide the heat transfer surfaces during the storage and discharge stage. The effects of steam flow rates, flow direction of steam in the storage tank and the initial temperature of storage and discharge tank on the heat transfer were tested.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.7
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• pp.417-427
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• 2014

Renewable energy sources such as solar, wind and hydro provides utilizing renewable power and reduce the using fossil fuels. On the other hand, it is too critical to apply power system due to the intermittent nature of renewable energy sources, the continuous fluctuations of the power load, and the storage with high energy density. Energy storage system, including pumped-hydroelectric energy storage, compressed-air energy storage, superconducting magnetic energy storage, and electrochemical devices like batteries, supercapacitors and others have shown that solve some of the challenges. In this paper, we review the current state of applications of energy storage systems, and atomic layer deposition technology, graphene materials on the energy storage systems and processes.

• Transactions of the Korean hydrogen and new energy society
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• v.21 no.1
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• pp.58-63
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• 2010

Mg and Ma-based alloys are promising hydrogen storage materials for renewable clean energy applications. It has high hydrogen storage capacity (7.6wt.%), lightweight and low economical materials. However, commercial applications of the Mg hydride are currently hindered by its high operating temperature, and very slow reaction kinetics. In this work, we are aimed at studying the hydrogenation properties of the $MgH_x-V_2O_5$ composite prepared by hydrogen induced mechanical alloying. The absorption capacity of the sample is found to be about 4.7wt.% at 623K under 3 MPa $H_2$ pressure. The absorption characteristics observed have been compared with prepared $MgH_x$.