• Journal of Institute of Convergence Technology
• /
• v.3 no.2
• /
• pp.7-10
• /
• 2013

Metal oxides are known as stable materials during a thermal treatment. However, some oxides are readily evaporated at high temperatures. A voloxidation process is a head-end process for a pyroprocessing dealing with spent nuclear fuels (SF). In SFs, fission productions are in the form of oxides and some of them would be evaporated during the voloxidation process. Therefore, it is of importance to analyse the vapor pressures of metal oxides so that the material flows throughout the pyroprocessing could be estimated. In this work, vapor pressures of relevant metal oxides were calculated and presented to draw a baseline on the material flow of the pyroprocessing.

• Korean Chemical Engineering Research
• /
• v.50 no.6
• /
• pp.1082-1085
• /
• 2012

CdTe nanoribbons feature their unique optical properties compared with CdTe nanoparticles. Slow oxidation of tellurium ions on CdTe nanoparticles resulted in the organization of individual nanoparticle into nanoribbons. The light-controlled self-assembly of CdTe nanoparticles led to twisted ribbons. It was found that irradiation improved the oxidation of tellurium ions. Transmission electron microscopy (TEM) were performed to characterize the synthesized nanostructures and showed nanowires were twisted after self-assembly. The photoluminescence was slightly blue-shifted from 550 to 544 nm. This synthetic procedure could potentially provide a key step toward the fabrication of nanowires.

• Journal of the Korean Chemical Society
• /
• v.56 no.4
• /
• pp.530-534
• /
• 2012

• Bulletin of the Korean Chemical Society
• /
• v.35 no.1
• /
• pp.293-296
• /
• 2014

• Safety and Health at Work
• /
• v.9 no.2
• /
• pp.159-163
• /
• 2018

Background: Fatigue and sleepiness are inter-related and common among road transport drivers. In this study, sleep deprivation and fatigue among chemical transportation drivers were examined. Methods: A cross-sectional study surveying 107 drivers from three hazardous types of chemical production and transportation industries (nonflammable gases, flammable gases, and flammable liquids) was conducted. Data on sleep deprivation were collected using questionnaires of the Stanford Sleeping Scale and the Groningen Sleep Quality Scale. Fatigue was assessed using an interview questionnaire and a flicker fusion instrument. Results: Chemical drivers had a mean sleeping scale (Stanford Sleeping Scale) of 1.98 (standard deviation 1.00) and had a mean score of 1.89 (standard deviation 2.06) on the Groningen Sleep Quality Scale. High-risk drivers had higher scores in both the Stanford Sleeping Scale and the Groningen Sleep Quality Scale with a mean score of 2.59 and 4.62, respectively, and those differences reached statistical significance (p < 0.05). The prevalence of fatigue, as assessed through a critical flicker fusion analyzer, subjective fatigue question, and either of the instruments, was 32.32%, 16.16%, and 43.43%, respectively. Drivers who slept <7 hours and had poor sleep quality were found to have more fatigue than those who slept enough and well. Drivers who had a more sleepiness score resulted in significantly more objective fatigue than those who had a less sleepiness score. Conclusion: Sleep quality and sleeping hour can affect a driver's fatigue. Optimization of work-rest model should be considered to improve productivity, driver retention, and road safety.

• Journal of the Korea Safety Management & Science
• /
• v.14 no.3
• /
• pp.21-31
• /
• 2012

This study was conducted in order to assist with infusing safety consciousness and resolving insensitivity towards safety for industrial accident in workers, managers and executives of chemical companies. Among many industrial accident prevention methods, Korea has been mostly taking an engineering approach of preventing industrial accidents by replacing old machines with risks of an accident and through new facilities and equipments. Through an attitude survey of workers in large scale chemical companies, this study wished to examine the fact that the biggest reason why the accident rate for the past 10 years has not decreased is because safety consciousness has not been established yet.

• Journal of Institute of Convergence Technology
• /
• v.4 no.1
• /
• pp.5-8
• /
• 2014

Recently ionic liquids received much attention as novel materials capable of replacing traditional solvents. The applicability of the ionic liquids should be determined based on their physico-chemical properties. Heat capacity is one of the most important properties to be considered when a process is developed using the ionic liquids and currently DSC has been proved as an effective technique to measure the heat capacity. Micro DSCII can measure heat capacities of various liquids by both an isothermal step method and a scanning method. DSC Q100 and MDSC are able to measure heat capacities of several ionic liquids. For each ionic liquid linear regression of the heat capacity as a function of temperature has been performed to increase accuracy. To investigate the feasibility of ionic liquids as PCMs, their heat capacities have been measured by using Pysis I DSC. This paper briefly summarizes the present techniques of measuring heat capacities of ionic liquids by DSC.

• Journal of the Korean Institute of Gas
• /
• v.25 no.4
• /
• pp.1-9
• /
• 2021

The process and facilities of modern chemical plants are becoming increasingly complex, there is possibility of potential risk. Internal chemicals generate stress concentration when operated due to turbulence, laminar flow, pressure, temperature, friction, etc. It causes cumulative fatigue damage, which can damage or rupture chemical facilities and devices. The statistics of chemical accidents found that the highest rate of occurrence was in summer, and in the last five years statistics on chemical accidents, leakage incidents make up a decent percentage of accidents. Chemical leaks can cause serious human damage and economic damage, including explosions and environmental pollution. In this study, based on the leak accident of chemical plant, the risk analysis, and damage effects assessment were estimated using a 3D scanner and FLACS. As a result, if chemicals leak in summer, the risk is higher than in other seasons, the seasonal safety management measures, and countermeasure were estimated.

• The Korean Journal of Food And Nutrition
• /
• v.30 no.5
• /
• pp.1042-1047
• /
• 2017

In order to improve the usability of mealworm and the nutritional quality of acorn Mook mostly composed of carbohydrates, we prepared acorn Mook using with different levels of mealworm powder, and the physico-chemical and sensory evaluation were investigated. In the content of proximate chemical composition, moisture content did not show any significant difference. But crude protein, crude ash, and crude fat contents were increased with increasing mealworm content. Carbohydrate content was reduced as mealworm content increased. Lightness showed no significant difference among treatments, redness was increased, and yellowness was decreased as the amount of mealworm powder increased. In physiological properties, hardness, gumminess, chewiness, and springiness were significantly increased as the amount of mealworm powder decreased. However, adhesiveness and cohesiveness were not significantly different. Ascorbic acid content, activities of DPPH and ABTS radical scavenging activities were decreased with increasing amount of mealworm in acorn Mook. In sensory evaluation, acorn Mook containing 0.75% of mealworm powder showed highly preference compared with the control.

• Asian Journal of Atmospheric Environment
• /
• v.10 no.1
• /
• pp.51-56
• /
• 2016

Particulate matter (PM) in the atmosphere has wide-ranging health, environmental, and climate effects, many of which are attributed to fine-mode secondary organic aerosols. PM concentrations are significantly enhanced by primary particle emissions from traffic sources. Recently, in order to reduce $CO_2$ and increase fuel economy, gasoline direct injected (GDI) engine technology is increasingly used in vehicle manufactures. The popularization of GDI technique has resulted in increasing of concerns on environmental protection. In order to better understand variations in chemical composition of particulate matter from emissions of GDI vehicle versus a port fuel injected (PFI) vehicle, a high time resolution chemical composition of PM emissions from GDI and PFI vehicles was measured at facility of Transport Pollution Research Center (TPRC), National Institute of Environmental Research (NIER), Korea. Continuous measurements of inorganic and organic species in PM were conducted using an Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS). The HR-ToF-AMS provides insight into non-refractory PM composition, including concentrations of nitrate, sulfate, hydrocarbon-like and oxygenated organic aerosol, and organic mass with 20 sec time resolution. Many cases of PM emissions during the study were dominated by organic and nitrate aerosol. An overview of observed PM characteristics will be provided along with an analysis of comparison of GDI vehicle versus PFI vehicle in PM emission rates and oxidation states.