• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.47 no.6
• /
• pp.726-732
• /
• 2014

A traditional Korean seafood (fermented anchovy) is made from the muscle and viscera of anchovies Engraulis japonica. This study was undertaken to investigate the effect of retorting condition on the quality of canned, salt-fermented anchovy fillet using red pepper paste with vinegar. Salt-fermented anchovy fillets were prepared by fermenting anchovies with salt (15%) at $5^{\circ}C$ for 15 days, and then cold air drying the fillets for 1 hour. Each batch of dried fermented anchovy fillets (60 g) was filled with 35 g of mixed red pepper paste with vinegar (red pepper paste 64%, vinegar 2%, starch syrup 13%, sugar 14%, coke 6%, soju 0.4%, crushed garlic 0.3%, ginger 0.3%), placed in a can (RR-90), seamed using a vacuum seamer, and sterilized for either Fo 9 or 11 min in a steam system retort at $121^{\circ}C$. After sterilization, we measured the pH, total volatile basic nitrogen (TVB-N), amino-N, color value (L, a, b), texture profile, thiobarbituric acid (TBA) value, sensory evaluation, and viable bacterial count of the canned fillets. We did not detect viable bacterial counts in cans subjected to either sterilization treatment, and there was no difference in physicochemical and sensory quality between the two. In fact, most sensory evaluators reported difficulty distinguishing the products. Thus, our results show that sterilization for Fo 9 min is preferable to that for Fo 11 min in the preparation of canned salt-fermented anchovy fillet using red pepper paste with vinegar.

• Korean Chemical Engineering Research
• /
• v.53 no.3
• /
• pp.372-381
• /
• 2015

The effect of preparation method on the catalytic activities of the $Ni/Al_2O_3$ catalysts on steam reforming of ethylene glycol was investigated. The catalysts were prepared with various preparation methods such as an incipient wetness impregnation, wet impregnation, and coprecipitation method. In the case of coprecipitation method, various precipitants such as KOH, $K_2CO_3$, and $NH_4OH$ were compared. The prepared catalysts were characterized by using $N_2$ physisorption, inductively coupled plasma-atomic emission spectroscopy, X-ray diffraction, temperatureprogrammed reduction, pulsed $H_2$ chemisorption, temperature-programmed oxidation, scanning electron microscopy, and thermogravimetric analysis. Among the catalysts reduced at 773 K, the $Ni/Al_2O_3$ catalyst prepared by a coprecipitation with KOH or $K_2CO_3$ as precipitants showed the best catalytic performance. The preparation method affected the particle size of Ni, reducibility of nickel oxides, catalytic performance (activity and stability), and types of coke formed during the reaction. The $Ni/Al_2O_3$ catalyst prepared by a coprecipitation with KOH showed the increasing catalytic activity with an increase in the reduction temperature from 773 to 1173 K because of an increase in the reduction degree of Ni oxide species even though the particle size of Ni increased with increasing reduction temperature.

• Safety and Health at Work
• /
• v.8 no.1
• /
• pp.99-104
• /
• 2017

Background: Workers laboring in steel industries in tropical settings with high ambient temperatures are subjected to thermally stressful environments that can create well-known risks of heat-related illnesses and limit workers' productivity. Methods: A cross-sectional study undertaken in a steel industry in a city nicknamed "Steel City" in Southern India assessed thermal stress by wet bulb globe temperature (WBGT) and level of dehydration from urine color and urine specific gravity. A structured questionnaire captured self-reported heat-related health symptoms of workers. Results: Some 90% WBGT measurements were higher than recommended threshold limit values ($27.2-41.7^{\circ}C$) for heavy and moderate workloads and radiational heat from processes were very high in blooming-mill/coke-oven ($67.6^{\circ}C$ globe temperature). Widespread heat-related health concerns were prevalent among workers, including excessive sweating, fatigue, and tiredness reported by 50% workers. Productivity loss was significantly reported high in workers with direct heat exposures compared to those with indirect heat exposures ($x^2=26.1258$, degrees of freedom = 1, p < 0.001). Change in urine color was 7.4 times higher among workers exposed to WBGTs above threshold limit values (TLVs). Conclusion: Preliminary evidence shows that high heat exposures and heavy workload adversely affect the workers' health and reduce their work capacities. Health and productivity risks in developing tropical country work settings can be further aggravated by the predicted temperature rise due to climate change, without appropriate interventions. Apart from industries enhancing welfare facilities and designing control interventions, further physiological studies with a seasonal approach and interventional studies are needed to strengthen evidence for developing comprehensive policies to protect workers employed in high heat industries.

• Resources Recycling
• /
• v.25 no.1
• /
• pp.48-59
• /
• 2016

The earth has been warming due to $CO_2$ gas emissions from fossil fuel cars and a ship. So the hydrogen fuel cell vehicle(FCV) using hydrogen as a fossil fuel alternative energy is in the spotlight. Hyundai Motor Company of Korea and a car companies of the US, Japan, Germany is developing a FCV a competitive. Obtained hydrogen as a by-product of the coke plant, oil refineries, chemical plants of steel mill, coal is reacted with steam at high temperatures, methane gas, manufacture of high purity hydrogen Methane Steam Reforming and hydrogen detachable reforming method using the Pressure Swing Adsorption or Membrane Reforming technical or decomposition of water to produce electricity. Hydrogen is the electronic industry, metal and chemical industries, which are used as rocket fuel, etc. are used in factories, hospitals, home of the fuel Ene.Farm system or FCV. And a method of storing hydrogen is to store liquid hydrogen and a method for compressing normal hydrogen to the hydrogen container, by storing the latest hydride or Organic chemical hydride method is used to carry the hydrogen station. Korea is currently 13 hydrogen stations in place and in operation, plans to install a further 43 places.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.10 no.9
• /
• pp.2478-2484
• /
• 2009

The purpose of this study is to conduct an oral examination of total 220 students (1st grade) at S Boys' High School in Seoul metropolitan City. The results of oral examination can be outlined as follows: According to survey on experience of oral symptoms 85.5% students had no experience of tooth fracture, 76.8% students had no experience of hemodia, and 90.9% students had no experience of toothache. And it was found that 86.4% students had no experience of periodontal disease, 98.2% students had no experience of intraoral pain, and 88.2% had no experience of subjective halitosis symptom. According to survey on oral health behaviors, 73.6 % students had no experience of visiting any dental clinic over last one year. In particular, it was found that 57.3% students brushed their teeth after breakfast every day, 19.1% students didn't enjoy having any confectionery or sweet stuff, or taking soft drink like coke on a daily basis, and 19.5% students used fluoride toothpaste for toothbrushing as of this survey. According to oral health examination, 55.9% students had no dental caries, and 44.1% students had dental caries. And it was found that most students (79.2%) had dental calculus resulting from periodontal disease.

• Journal of Nutrition and Health
• /
• v.38 no.6
• /
• pp.419-431
• /
• 2005

The prevalence of atopic dermatitis (AD) continues to increase in the industrialized countries related to Western lifestyle and dietary patterns. The purpose of this study was to evaluate the nutritional status, dietary patterns and dietary quality of AD patients. AD patients (n=50) and gender age matched healthy control (HC) were studied in case-control clinical trail. Preference and frequencies of consumption for 98 foods were estimated by questionnaires. Dietary pattern, current nutrients intake, and dietary quality were evaluated by the 3-day food records. As a result, anthropometric measurements from HC and AD patients were not significantly different. AD patients had significantly lower preference for buckwheat, some fishes (shellfish, flatfish, salmon), egg yolk, some vegetables (onion, garlic, Chinese-cabbage, radish, pepper, mushroom), coffee, and snack than those of HC had (p<0.05). AD patients had significantly lower frequency for pea, some fishes (shellfish, herring, flatfish, salmon, codfish), egg, some vegetables (spinach, pumpkin, mushroom), margarine/butter, nuts, coffee and apple juice, fried chicken, coke than those of HC had (p<0.05). The intake of vitamin $B_1$, vitamin $B_2$ (p<0.05) and vitamin E (p<0.001) of AD patients were significantly lower than those of HC. The intake for Ca and Zn of AD patients were remarkably lower than RDA for each nutrient. Moreover, AD patients' index of nutritional quality (INQ) and nutrient adequacy ratio (NAR) of vitamin E, vitamin $B_1$, vitamin $B_2$ were lower than those of HC. AD patients' dietary quality including dietary diversity score (DDS), dietary variety score (DVS), DMGFV (dairy, meat, grain, fruit, vegetable), dietary quality index (DQI) was poor. This results indicate that atopic dermatitis patients had significantly different food preference and food frequency when these were compared with those of healthy people. The dietary diversity, dietary variety and dietary quality of atopic dermatitis patients were very limited.

• Resources Recycling
• /
• v.29 no.4
• /
• pp.3-14
• /
• 2020

Titanium sponge is industrially produced by the Kroll process. In order to understand the importance of the emerging smelting and recycling process, it is necessary to review the conventional production process of titanium. Therefore this paper provides a general overview of the conventional titanium manufacturing system mainly by the Kroll process. The Kroll process can be divided into four sub-processes as follows: (1) Chlorination of raw TiO₂ with coke, by the fluidized bed chlorination or molten salt chlorination (2) Magnesium reduction of TiCl₄ and vacuum distillation of MgCl₂ and Mg by reverse U-type or I-type with reduction-distillation integrated retorts (3) Electrolysis process of MgCl₂ by monopolar cells or multipolar cells to electrolyze into chlorine gas and Mg. (4) Crushing and melting process in which sponge titanium is crushed and then melted in a vacuum arc furnace or an electron beam furnace Although the apparatus and procedures have improved over the past 80 years, the Kroll process is the costly and time-consuming batch operation for the reduction of TiCl₄ and the separation of MgCl₂.

• Applied Chemistry for Engineering
• /
• v.29 no.6
• /
• pp.652-656
• /
• 2018

In this study, effects of the reaction pressure were studied for petroleum-based pitch synthesis. A two-stage reaction process was performed based on different reaction pressure conditions. Each stage experiments for the two-stage reaction were consecutively carried out. The first stage was consisted of three different pressure conditions; high (10 bar), normal and low (0.1 bar). And the second stage was carried out at the normal and low (0.1 bar) pressure. The pitch synthesis was realized at $400^{\circ}C$ for 2 h. Thermal properties and molecular weight distributions of each samples were investigated by analyzing the softening point and MALDI-TOF data. Volatilized components during the pith synthesis were measured by GC-SIMDIS. In case of the first-step reaction with the high pressure condition, the low molecular weight component participated to the pitch formation more effectively and the pitch with the low softening point was obtained. However, for the case of the first-step with the low pressure, the low molecular weight component was vent outside and the partial coke formation occurred. Eventually, pitch properties such as the softening point and yield were controlled effectively by changing the pressure in the pitch synthesis reaction.

• Resources Recycling
• /
• v.28 no.4
• /
• pp.44-50
• /
• 2019

In the electric arc furnace process, the chemical energy such as the heat of oxidation reaction and the heat of carbon combustion etc. is consumed as 30% of the total input energy. In order to reduce $CO_2$ emission in EAF, it is necessary to decrease the use of electric power energy during scrap melting stage and increase the use of chemical energy. In general, when the carbon materials is individually charged into the molten steel, the carbon materials floated to the slag layer due to low density before it is dissolved in molten steel. When the concentration of carbon in the molten steel is high, the combustion energy of carbon by oxygen injection can lower the electric power energy and improve the chemical energy consumption. Therefore, an efficient charging methods of carbon material is required to increase the efficiency of carbon combustion heat. On the other hand, Al-dross, which is known as a by-product after Al smelting, includes over 25 mass% of metallic Al, and the oxidation heats of Al is lager than that of carbon. However, the recycling ratio fo Al-dross was very low and is almost landfilled. In order to effectively utilize the heats of oxidation of Al in Al-dross, it is necessary to study the application of Al-dross in the steel process. In this study, the dissolution efficiency of carbon and aluminum in molten steel was investigated by varying the reaction temperature and the mixing ratios of coke and Al-dross.

• Applied Chemistry for Engineering
• /
• v.31 no.6
• /
• pp.688-696
• /
• 2020

Petroleum coke (petcoke) is widely used, next to coal, as a gasification feedstock. In gasification processes, the viscosity of the ash and the formation of crystalline phases must be understood to ensure the continuous removal of slag. This study investigates the effect of CaO and V2O3 on petcoke slag viscosity. The viscosity of the molten slag was measured in the temperature range of 1100~1600 ℃ while varying the concentration of each component. The crystalline phases formed in a cooled slag were examined. The most slag samples tested in this study exhibited crystalline slag behavior. The increased CaO concentration resulted in a lower viscosity and a lower Tcv. The viscosity behavior changed from the glassy to crystalline slag and also showed a higher Tcv as the concentration of V2O3 increases. Most slag samples showed different crystalline phases from top to bottom. Anorthites and Ca-V phases were observed in the top and middle section, while the bottom section mainly showed V2O3 and anorthite. The vanadium in the ash forms Ca-V and V-Fe phases and also remains in molten slag. A low melting Ca-V phase can contribute to lowering the viscosity.