• Journal of Environmental Health Sciences
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• v.49 no.6
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• pp.305-311
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• 2023

Background: The National Institute of Environmental Research (NIER)'s classification of and airborne fraction ratio for consumer chemical products (CCP) does not reflect the characteristics of various product classifications. Objectives: The purpose of this study was to reclassify the types of spray products according to the diverse spray characteristics of CCPs to evaluate the airborne fraction ratio of representative spray types and to compare them with previous CCPs types and airborne fraction ratios. Methods: One thousand seven hundred two products were selected through market research, and 932 newly reported products were selected. After that, 200 were selected to evaluate products with potential inhalation exposure. After classifying six product types that are expected to show differences in the airborne fraction ratio according to the type of product, a final 38 products were selected for use in the airborne fraction ratio through random sampling. Results: CCP has been reclassified from two to six types so that the characteristics of all products are well-reflected. The NIER simply had two airborne fraction ratios, but the results of experiments with six types of products showed a significant difference in values (p<0.01). Airborne fraction ratios of propellant general foam, pump general aerosol, and pump trigger foam in spray type, which were not previously present in NIER, were 7.1%, 24.4%, and 3.5%, respectively. Conclusions: For the diversified types of CCPs, the newly proposed classification was more appropriate than the existing NIER classification. The airborne fraction ratio was also different for each type, so a new value was suggested.

• Journal of Hydrogen and New Energy
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• v.7 no.1
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• pp.93-110
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• 1996

금속수소화물은 열에너지 및 수소저장 또는 에너지변환장치 등에 많은 응용이 기대되고 있다. 특히 금속수소화물을 이용한 최근의 에너지 변환기술은 기술적으로 뿐만 아니라 경제성면에서도 그 가능성이 한층 높아지고 있다. 본문에서는 이와 같은 열변환장치의 하나인 열펌프의 제작에 필요한 동적특성을 P-C-T, 열 및 물질전달, 흡 탈착반응속도 그리고 성능 등의 관계에서 그 발전과정을 살펴보고, 그밖에 실용화에 따른 문제성도 논의하였다.

• Proceedings of the KIPE Conference
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• 2015.07a
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• pp.293-294
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• 2015

This paper proposed a design and operation of energy storage system using Zinc-Bromine flow battery. To operate flow battery system with BMS, it uses motor drive system to pump electrolyte. it also needs sensors to check leaking and temperature. The proposed system proves the validity by experiment.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1994.11a
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• pp.43-47
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• 1994

화학 열펌프 시스템의 반응기 설계를 위하여 정적 설계의 결과를 이용하여 시간에 따른 전화율, 온도, 압력, 출력 등의 변화에 대한 모사를 시도하였다. 정적 모사를 통한 설계결과는 동적 거동 모사의 결과와 유사하였으며, 이로부터 정적모사가 동적모사를 위한 적절한 초기치와 기초 설계 정보를 제공함을 알 수 있었다. 본 연구를 통하여 확립된 설계절차와 해석방법에 따른 사례연구를 통하여 향후 실용화될 화학 열펌프 시스템의 개략적인 사양과 바람직한 설계방향을 제시 할 수 있었으며, 반응기의 조작에 따른 제어변수의 영향을 평가하는 기준을 마련할 수 있었다.

• Applied Chemistry for Engineering
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• v.8 no.5
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• pp.872-879
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• 1997

The nonuniform thermal conductive reaction blocks were manufactured by impregnation of metal salts on the expanded graphite to improve the heat and mass transfer ability of reaction block for the chemical heat pump using the reaction of ammonia and metal salts(halide). The nonuniform blocks were designated to increase apparent density, like 165, 222, 279, 337, $394kg/m^3$ radially The experimental results showed that the heat transfer characteristics of nonuniform blocks were better than uniform blocks. As the reaction of ammonia repeated, the volumetric expansion in the reaction block makes the mass transfer improve, and the reproducibility better.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.1
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• pp.51-58
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• 2021

Chemical decontamination of primary systems in a nuclear power plant (NPP) prior to commencing the main decommissioning activities is required to reduce radiation exposure during its process. The entire process is repeated until the desired decontamination factor is obtained. To achieve improved decontamination factors over a shorter time with fewer cycles, the appropriate flow characteristics are required. In addition, to prepare an operating procedure that is adaptable to various conditions and situations, the transient analysis results would be required for operator action and system impact assessment. In this study, the flow characteristics in the steady-state and transient conditions for the chemical decontamination operations of the Kori-1 NPP were analyzed and compared via the MARS-KS code simulation. Loss of residual heat removal (RHR) and steam generator tube rupture (SGTR) simulations were conducted for the postulated abnormal events. Loss of RHR results showed the reactor coolant system (RCS) temperature increase, which can damage the reactor coolant pump (RCP)s by its cavitation. The SGTR results indicated a void formation in the RCS interior by the decrease in pressurizer (PZR) pressure, which can cause surface exposure and tripping of the RCPs unless proper actions are taken before the required pressure limit is achieved.

• Korean Chemical Engineering Research
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• v.45 no.4
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• pp.328-334
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• 2007

Chemical heat pump system of 2-propanol/acetone/hydrogen is most suitable to the recovery of waste heat of power plant. various types of 5 wt% Pt-alumina catalysts were prepared for 2-propanol dehydrogenation using sol-gel method. The characteristics and the dehydrogenation reaction rate of each catalyst were investigated. Pt-alumina xerogel catalyst has excellent reaction rate and good durability in comparison with the existing alumina supported Pt catalysts. Pt-alumina aerogel catalyst had the highest reaction rate in all prepared catalysts, but sufficient aging time was necessary to maintain its reaction rate. A potential advantage of the aerogel catalyst is the fact that the high temperature heat treatment is not required. Without heat treatment or with low temperature heat treatment, the Pt-alumina aerogel catalyst has excellent reaction rate as well as durability and this gives us the economic advantage. Alumina xerogel supported Pt catalyst prepared by incipient wetness method showed good reaction rate, and had good mechanical strength. Blank alumina xerogel prepared by sol-gel method can be used for the support of metal catalysts.

• Bulletin of the Korean Chemical Society
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• v.24 no.8
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• pp.1075-1080
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• 2003

We have investigated femtosecond coherent vibrational motions of Zn(II)-5,15-diphenylporphyrin in toluene using chirp-controlled ultrashort pulses. The oscillatory features superimposed on the temporal profiles of the pump-probe transient absorption signal are affected by the chirping and energy of excitation pulses. Using chirp- and excitation energy-controlled femtosecond pulses, we are able to obtain information on the structural changes between the electronic ground and excited states based on a comparative analysis of the Fouriertransformed frequency-domain spectra retrieved from the oscillatory components with the ground state resonance Raman spectra and normal mode calculations.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2010.04a
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• pp.151-157
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• 2010

• Bulletin of the Korean Chemical Society
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• v.35 no.11
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• pp.3209-3212
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• 2014

This paper describes a selective synthetic method of fabricating Ag nanowires by using a modified polyol process. To synthesize the Ag nanowire, an ethylene glycolic solution of silver nitrate and an ethylene glycolic solution of polyvinylpyrrolidone solution containing a small amount of organic oxidant, 1,4-benzoquinone, were slowly added to a hot ethylene glycol medium at $160^{\circ}C$ for 8 min using a syringe pump. The reaction mixtures were heated for an additional 45 min and cooled to room temperature. Finally, the silver nanomaterials were isolated from the mixture by centrifugation. The crystal structure of the nanomaterials was investigated by powder X-ray diffraction analyses, and their morphology was investigated by scanning electron microscopy. A small amount of organic oxidant, 1,4-benzoquinone, played a significant role in controlling the morphology during crystal growth. Consequently, Ag nanowires rather than Ag nanoparticles were selectively obtained.