• Journal of the Korean Society for Heat Treatment
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• v.36 no.1
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• pp.22-32
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• 2023

In general, when scrap is dissolved in an electric arc furnace, the amount of electric furnace steel dust (EAFD) generated is about 1.5% of the scrap charge amount, and the electric furnace steel dust collected by the bag filter is charged into the Rotary Kiln or Rotary Hearth Furnace (RHF), and the zinc component is recovered as crude zinc oxide, at which time a clinker of Fe-Base is generated. In this research, first, for the efficient resource conversion of electric furnace steel dust, a reduction and roasting experiment was conducted and the reaction kinetics was examined. As a result of the experiment, it was observed that the reduction and roasting reaction was actively conducted in the range of 1100~1150℃, and melting occurred in the range of 1250℃. In the past, this clinker was widely used as a roadbed material for road construction and an Fe-Source for cement production, but in recent years, it has been mainly reclaimed due to strengthening environmental standards. However, landfill treatment is by no means a desirable treatment method due to environmental pollution caused by leachate, expensive landfill costs, and waste of Fe resources. Therefore, in order to more actively recycle the Fe component in the clinker, first of all the clinker was pulverized into an optimal particle size, and anthracite and binder (starch) were added to the magnetic material obtained by specific gravity and magnetic separation for briquet. As a experimental results, it was possible to efficiently separate clinker as Fe component and other slag component by specific gravity and magnetic force. As a results of loading and dissolving the manufactured briquet clinker in an electric arc furnace, it was observed that the unit of power and production yield were clearly improved and the carbon addition effect in molten metal was also somewhat.

• Resources Recycling
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• v.28 no.6
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• pp.79-86
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• 2019

Recently, the use of lithium ion battery(LIB) has increased. As a result, the price of lithium and the amount spent lithium on ion battery has increased. For this reason, research on recycling lithium in waste LIBs has been conducted1). In this study, the effect of roasting for the selective lithium leaching from the spent LIBs is studied. Chemical transformation is required for selective lithium leaching in NCM LiNi_xCo_yMn_zO₂) of the spent LIBs. The carbon in the waste EV cell powder reacts with the oxygen of the oxide at high temperature. After roasting at 550 ~ 850 ℃ in the Air/N₂ atmosphere, the chemical transformation is analysed by XRD. The heat treated powders are leached at a ratio of 1:10 in D.I water for ICP analysis. As a result of XRD analysis, Li₂CO₃ peak is observed at 700 ℃. After the heat treatment at 850 ℃, a peak of Li₂O was confirmed because Li₂CO₃ is decomposed into Li₂O and CO₂ over 723 ℃. The produced Li₂O reacted with Al at high temperature to form LiAlO₂, which does not leach in D.I water, leading to a decrease in lithium leaching ratio. As a result of lithium leaching in water after heat treatment, lithium leaching ratio was the highest after heat treatment at 700 ℃. After the solid-liquid separation, over 45 % of lithium leaching was confirmed by ICP analysis. After evaporation of the leached solution, peak of Li₂CO₃ was detected by XRD.

• Journal of the Korean Ceramic Society
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• v.28 no.6
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• pp.471-477
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• 1991

Effects of ZnO, PbO and SiO2 on the grain growth and magnetic properties of Sr-ferrite were investigated. (1) Addition of ZnO to Sr-ferrite increased remanence, but decreased coercivity and maximum energy product. (2) Addition of PbO up to 0.5 wt% increased (B$.$H)max of Sr-ferrite, but addition more than 0.5 wt% decreased (B$.$H)mzx (3) SiO2 addition to the 0.5 wt% PbO doped Sr-ferrite decreased remanence and increased coercivity. The coercivity increase in due to the grain refinement effect of SiO2. But addition of SiO2 more than 0.5 wt% invoked a decrease of coercivity and (B$.$H)max of Sr-ferrite due to abnormal grain growth. Sr-ferrite magnet having maximum energy product of 3.7MGOe was fabricated by using the roasting product of Pyrrhotite.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.8
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• pp.1179-1186
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• 2010

The antiradical property of hot water extract from dried radish (DR) or dried radish roasted with pressure (DRRP) was investigated in vitro and in LLC-PK1 cell system. The contents of total free amino acid and reducing sugar in DR were decreased by 72.86% and 3.17%, respectively, after pressurized roasting. In vitro test, $IC_{50}$ for DR and DRRP for DPPH radical scavenging activity were 646.70 and $135.45\;{\mu}g/mL$, 896.10 and $566.98\;{\mu}g/mL$ for superoxide anion radical, and 722.26 and $531.84\;{\mu}g/mL$ for hydroxy radical, respectively. The radical scavenging effects of DRRP was significantly greater than those for DR (p<0.001). These radical scavenging effects of DR and DRRP were confirmed in LLC-$PK_1$ at which oxidative stresses were induced by superoxide, nitric oxide and peroxynitrite generated in the treatment of pyrogallol, SNP, and SIN-1, respectively. Cell viability was increased in the presence of DR or DRRP, dose dependently (p<0.05), and TBARS formation was decreased. The protective effects of DRRP against oxidative damage in LLC-$PK_1$ were greater than those of DR at the same concentration tested (p<0.05). This superior antiradical activity of DRRP might be due to the products produced during the pressurized roasting in addition to the antioxidative compounds originally present in the radish. 5-hydroxyl methyl furfural (5-HMF) known as an intermediate product of the maillard reaction was detected in DRRP (0.57 mg/g), but not from DR. In conclusion, daily consumption of DRRP may prevent oxidative damage by retarding oxidative stress.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.905-913
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• 2003

The physicochemical properties of rice flour roasted at various temperatures and times were analyzed, and the quality characteristics of tarakjuk made from these roasted rice flours were investigated. As roasting temperature and time increased, rice flour showed decreasing moisture, protein content, and glucose the major reducing sugar of rice flour. Total amino acid content did not show any significant changes, but the amount of free amino acids and individual amino acids, such as lysine, tryptophane, and tyrosine, decreased. A decrease in L value and increases in a and b values from both roasted rice flour and tarakjuk was observed. Reduced crystallinity and gelatinization temperatures of roasted rice flour were investigated with X-ray diffractogram and DSC, respectively. The thermal transitions between $100.6{\sim}127.6^{\circ}C$ of tarakjuk by DSC are considered to be due to the melting of amylose-lipid complex. As the roasting temperature and time of rice flours increased, tarakjuk showed lower viscosity and higher spreadability. Sensory characteristics, such as nutty flavor, color intensity, and gritty texture increased significantly. Tarakjuk made from rice flour roasted at $185^{\circ}C$ for 25min showed the highest score on overall preference. From the above results, roasted rice flour produced more preferable tarakjuk than nonroasted flour in terms of sensory quality.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.3
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• pp.388-392
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• 2003

This study was conducted to examine the effect of soy flour on tapioca non- steamed fermentation. A whole soy flour was higher than roasting soy flour in alcohol content. Alcohol content was increased up to 2% of soy flour, and decreased after adding 3% soy flour. The pH and total acidity were showed no significant differences by adding soy flour, roasted soy flour, water and enzyme. The optimum conditions for alcohol production were 2% (w/w) of soy flour,0.5% (w/w) of enzyme and 250% (v/w) of water at 96 hr. Addition of soy flour increased yield of alcohol.

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1336-1341
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• 2009

Quantitative changes in functional constituents of waxy corn (Zea mays L.) by 5 different thermal pretreatments, including roasting, steaming, microwave, puffing, and extruding, were determined and compared with those of the raw waxy corn. There were no significant differences in fatty acid compositions among the corn treated with 5 thermal treatments. Levels of $\alpha$- and $\gamma$-tocopherols, soluble amino acids, and phytosterols decreased by thermal treatments, while those of p-coumaric and ferulic acids considerably increased by thermal treatments. In particular, the contents of tocopherols and phytosterols, and souble amino acid decreased significant in the steaming and puffing processes, respectively, whereas those of 2 free cinnamic acids increased significantly in the steaming and puffing processes. The extruding process showed smaller quantitative changes in tocopherols, phytosterols, and hydroxycinnamic acid derivatives compared to other heat pretreatments. These results suggest that the extruding process have a positive effect on valuable phytochemicals in waxy corn.

• Herbal Formula Science
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• v.27 no.4
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• pp.245-255
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• 2019

Objective : Herbal processing is one of the traditional techniques used in Korean medicine to increase the effectiveness of herbs or reduce their toxicity. In this study, Gardeniae Fructus processed with ginger juice and alcohol was prepared to evaluate the anti-inflammatory effect on lipopolysaccharide (LPS)-induced macrophages. Methods : The processing of Gardeniae Fructus was performed by adding 40 % ginger juice or 10% alcohol to the total weight of Gardeniae Fructus and then roasting at 150℃ for 5 minutes. Cell viability was determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. To detect nitric oxide (NO) production, culture media were mixed with Griess reagent and measured the absorbance at 540 nm. Prostaglandin E₂ (PGE₂) and pro-inflammatory cytokines were detected by enzyme-linked immunosorbent assay (ELISA). Western blot was applied to monitor protein expression levels. Results : LPS-induced NO, PGE₂ and inflammatory cytokines were decreased by the treatment of normal or processed Gardeniae Fructus ethanol extracts (GFE). Compared to normal GFE, the processed GFE showed a stronger inhibitory effect on the production of NO and PGE₂. These inhibitory effect of GFE was due to the suppression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) mediated from the inhibition of nuclear factor kappa B (NF-κB). Furthermore, processed GFE showed more suppressive effects on the expression of iNOS, COX-2 and IκBα proteins than normal GFE. Conclusion : From these results, it was concluded that GFE had an improved anti-inflammatory effect compared to normal GFE. These results provide an objective evidences for the use of herbal processing in Korean medicine.

• Korean Journal of Pharmacognosy
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• v.37 no.4 s.147
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• pp.246-252
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• 2006

Processing of traditional herbal medicine is one of the pharmaceutical technique in oriental medicine. Most frequently used processing method in oriental medicine are roasting and steaming. In this studies, to elucidate the pharmacological transformation of traditional herbal medicine by means of processing them, Ginseng Radix (root of Panax ginseng, Araliaceae) was used as a sample. Processed ginseng radix (SGR, Sun Ginseng) was prepared by steaming of roots of white ginseng (GR) for 3 hours at $120^{\circ}C$. The biological activities of methanol extract of GR and SGR were investigated. According to DPPH radical scavenging effects, and inhibitory effects of xanthine oxidase and AAPH induced hemolysis, PGR exhibited more effective than those of GR in vitro. And, the antifatigue effect of GR and SGR were investigated using a weight-loading forced swimming test by monitoring swimming times and prolonged intensity exercise model rats by measuring blood biochemical parameters. GR and SGR were significantly prolonged swimming times in 8% body weight ratio loaded mice. Also, they had the inhibitory effects on the decrease of blood glucose levels, the elevation of serum creatinine, lactic acid and free fatty acid, and lactic dehydrogenase activities in forces swimming rats with 1% of the body weight attached to the neck for 3 hours. SGR was more excellent than GR on these effect. Also, these effects were transformed to the n-butanol fraction of methanol extract of SGR. From these results, it can be considered that SGR has antifatigue effect.

• Korean Journal of Agricultural Science
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• v.43 no.1
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• pp.87-99
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• 2016

Phytosterol contents in nine vegetables such as paprika (red, yellow, and orange), kohlrabi, bamboo shoot, cherry tomato, cucumber, Chinese chive, and corn were analyzed by gas chromatography. Individual contents of ${\beta}$-sitosterol, campesterol, and stigmasterol in fresh and cooked vegetables (boiling, grilling, stir-frying, deep-frying, steaming, roasting, and microwaving) were determined and compared. Total phytosterol content of paprika, cucumber, Chinese chive and cherry tomato ranged from 23.19 to 46.51 mg/kg (0.002-0.005%) of fresh weight of raw vegetables. Total phytosterol content variation (%) was obtained as follows: [(the content of phytosterol after cooking) - (the content of phytosterol before cooking)] / (the content of phytosterol before cooking) ${\times}100$. Total phytosterol content was found to be high in raw kohlrabi at 138.99 mg/kg fw (0.01%), in corn at 302.86 mg/kg fw (0.03%), and in bamboo shoot at 443.15 mg/kg fw (0.04 %). Total phytosterol content variation (%) in orange paprika ranged from 27.5 to 267.3 while that in cherry tomato ranged from -11.0 to 337.5. Generally, high content variation of total phytosterol was found in stir-fried and deep-fried vegetables. Therefore, higher phytosterol levels were obtained from cooked vegetables than raw vegetables. We suggest that these data will be useful to investigate cooking methods for increased intake of phytosterols.