• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.3
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• pp.281-299
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• 2017

The inventory management of radionuclides is essential for the safe management of disposal facilities. In this study, we compared the activity of dry active waste predicted using the generated waste data and that measured for the accepted waste in the disposal facility. For very low level waste, the measured activity was higher than the predicted activity for $^{137}CS$, $^{90}Sr$, $^{99}Tc$ and $^{129}I$. In low level waste, the predicted activity was higher than the measured activity for all radionuclides. We also evaluated the variation in the predicted quantity and total activity of each level of dry active waste through a sensitivity analysis on a scaling factor. This result will contribute to the construction of a Safety Case and safe operation of disposal facilities.

• Nuclear Engineering and Technology
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• v.43 no.2
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• pp.149-158
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• 2011

Metal waste generated from the pyroprocessing of 10 MtU of spent fuel was classified by comparing the specific activity of a relevant radionuclide with the limit value of the specific activity specified in the Korean acceptance criteria for a lowand intermediate-level waste repository. A Korean Optimized Fuel Assembly design with a 17${\times}$17 array, an initial enrichment of 4.5 weight-percent, discharge burn-up of 55 GWD/MtU, and a 10-year cooling time was considered. Initially, the mass and volume of each structural component of the assembly were calculated in detail, and a source term analysis was subsequently performed using ORIGEN-S for these components. An activation cross-section library generated by the KENO-VI/ORIGEN-S module was utilized for top-end and bottom-end pieces. As a result, an Inconel grid plate, a SUS plenum spring, a SUS guide tube subpart, SUS top-end and bottom-end pieces, and an Inconel top-end leaf spring were determined to be unacceptable for the Gyeongju low- and intermediate-level waste repository, as these waste products exceeded the acceptance criteria. In contrast, a Zircaloy grid plate and guide tube can be placed in the Gyeongju repository. Non-contaminated Zircaloy cladding occupying 76% of the metal waste was found to have a lower level of specific activity than the limit value. However, Zircaloy cladding contaminated by fission products and actinides during the decladding process of pyroprocessing was revealed to have 52 and 2 times higher specific activity levels than the limit values for alpha and $^{90}Sr$, respectively. Finally, it was found that 88.7% of the metal waste from the 17${\times}$17 Korean Optimized Fuel Assembly design should be disposed of in a deep geological repository. Therefore, it can be summarized that separation technology with a higher decontamination factor for transuranics and strontium should be developed for the efficient management of metal waste resulting from pyroprocessing.

• Journal of Microbiology and Biotechnology
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• v.17 no.11
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• pp.1811-1817
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• 2007

Extracellular enzymes from Lentinus edodes M290 on normal woods (Quercus mongolica) and waste logs from oak mushroom production were comparatively investigated. Endoglucanase, cellobiohydrolase, ${\beta}$-glucosidase, and xylanase activities were higher on waste mushroom logs than on normal woods after 1. edodes M290 inoculation. Xylanase activity was especially different, with a three times higher activity on waste mushroom logs. When the waste mushroom logs were used as a carbon source, a new 35 kDa protein appeared. After the purification, the optimal pH and temperature for xylanase activity were determined to be 4.0 and $50^{\circ}C$, respectively. More than 50% of the optimal xylanase activity was retained when the temperature was increased from 20 to $60^{\circ}C$, after a 240 min reaction. At $40^{\circ}C$, the xylanase maintained 93% of the optimal activity, after a 240 min reaction. The purified xylanase showed a very high homology to the xylanase family 10 from Aspergillus terreus by LC/MS-MS analysis. The highest Xcorr (1.737) was obtained from the peptide KWI SQGIPIDGIG SQTHLGSGGS WTVK originated from Aspergillus terreus, indicating that the 35 kDa protein was xylanase. This protein showed low homology to a previously reported L. edodes xylanase sequence.

• Journal of Energy Engineering
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• v.27 no.1
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• pp.76-80
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• 2018

The objective of this research paper is to discuss the waste coffee residue disposal and its environmental effects on the environment. As we know, coffee is one of the most demand and swallowed beverages in the world, which leads to large quantities of solid waste. Which can be toxic and a lot of environmental problems occur. In developing countries, there is a lack of proper coffee waste residue management. The coffee beans and residues contain several organic compounds. The wastewater from coffee industry emitted several pollutants (highly concentrated) and it contaminates the soil, ground waters, aquatic life, and also human health. Hence it is essential to treat the coffee waste residues. Mean while, oyster shell waste and its disposal also a big environmental challenge in the coastal regions of southeast Korea. In this paper, we focused the treatment of coffee waste residue with oyster shell waste powder. Primarily, oyster shells are calcinated at higher temperatures and investigated the calcined CaO powder as an anti microbic agent to the bacteria presented in coffee waste residues. We successfully applied calcium oxide from oyster shell waste, as an antimicrobic agent.

• Mycobiology
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• v.35 no.4
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• pp.196-204
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• 2007

The growth and bioconversion potential of selected strains growing on cassava waste substrate during solid state fermentation were assessed. Rhizopus stolonifer showed the highest and the fastest utilization of starch and cellulose in the cassava waste substrate. It showed 70% starch utilization and 81% cellulose utilization within eight days. The release of reducing sugars indicating the substrate saccharification or degradation potential of the organisms reached the highest value of 406.5 mg/g by R. stolonifer on cassava waste during the eighth day of fermentation. The protein content was gradually increased (89.4 mg/g) on the eighth day of fermentation in cassava waste by R. stolonifer. The cellulase and amylase activity is higher in R. stolonifer than A. niger and P. chrysosporium. The molecular mass of purified amylase and cellulase seemed to be 75 KDal, 85 KDal respectively.

• Fisheries and Aquatic Sciences
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• v.21 no.10
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• pp.33.1-33.11
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• 2018

As a process for commercial application, production of reducing sugar, antioxidant, and DNA protective compounds from shrimp-shell powder was investigated in a fed-batch biodegradation using Bacillus cereus EW5. The fed-batch biodegradation was operated in a 5-L bioreactor for 96 h according to three times pulse-feeding strategy. On the basis of the equal working volume (3 L), the fed-batch biodegradation showed a better production of the target compounds than the batch biodegradation, with higher cell density and shortened biodegradation period. The maximum values of the target compounds were 0.297 mg/mL of reducing sugar, 92.35% DPPH radical scavenging activity, 98.16% ABTS radical scavenging activity, and 1.55 reducing power at $A_{700}$, which were approximately 12.1, 3.4, 5.2, and 8.4% enhanced, respectively, compared with those obtained from the batch biodegradation. The fed-batch culture supernatant also showed the enhanced DNA damage inhibition activity than the batch culture supernatant. As a result, the fed-batch biodegradation accompanied by high cell density could produce more useful compounds, enabling an increase in the reutilization value of shrimp-shell waste.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.5
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• pp.819-825
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• 2000

The physico-chemical characteristics and the combustion activities of a waste automotive catalyst were carried out in this study. The physico-chemical characteristics of waste automotive catalyst was examined by EA(Elemental analysis), ICP-AES (Inductively coupled plasma-atomic emission spectrophotometer), and XRD(X-ray diffraction) analysis. Carbon deposit amount was higher in front brick than rear brick of catalyst, and increased with mileage. The content of Pt. Pd and Rh in waste automotive catalyst was different from the car manufacturing company. The combustion activities of waste automotive catalyst were investigated for acetaldehyde as a model VOC in a fixed bed reactor at atmospheric pressure. The catalytic activity of rear brick for acetaldehyde combustion was better than front brick of waste automotive catalyst. The catalytic activity of waste automotive catalyst for acetaldehyde combustion decreased with mileage. The linear relationship between catalytic activity and mileage was negative and has a very excellent correlation. Finally, the waste automotive catalyst has a good catalytic activity for acetaldehyde combustion. and can be used to control of small emission source.

• Journal of the Korea Organic Resources Recycling Association
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• v.14 no.4
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• pp.141-150
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• 2006

To develop the microbial agents for the environmentally-friendly treatment and recycling of food waste, useful microorganisms, which showed higher degradation activities to various organic compounds and possessed flocculating activities, were isolated from the earthworm. One of the isolated strains, named JS-01, was further selected due to its higher flocculating activity against 0.5% Kaolin clay. JS-01 was identified as Bacillus pumilus sp. by 16s rDNA analysis. The optimal temperature and pH for the growth of JS-01 to express the flocculating activity was found to be at $37^{\circ}C$ in pH 7.0 of EPS broth medium. JS-01 also expressed good degrading activity against cellulose, which is one of the representative organic materials in food waste. We propose that JS-01 will be a good candidate for the efficient treatment of food waste and leachate due to the property to degrade cellulose and flocculating activity.

• Journal of Sericultural and Entomological Science
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• v.42 no.2
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• pp.109-113
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• 2000

The preparation of skin care gauze could be make to mixing separated cellulose from waste milk pack and degummed silk fibroin fiber. Also, its wound covering and anti-bacterial activity were investigated in order to find out the enhancement of their functionality. By the 30% silk fibroin fiber including skin care gauze, the anti-bacterial activity values of Staphylococcus strain are much 4 times higher than of 0∼10% silk fibroin fiber including skin care gauze. The average yield of cellulose from waste milk pack was obtained 50-60%, and their morphologies, physical properties, modulus and biodegradation ratios are studies, respectively.

• Korean Journal of Agricultural Science
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• v.43 no.5
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• pp.734-741
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• 2016

Lily (Lilium davidii) is a high-yielding flowering plant. Besides roses and chrysanthemums, lily bulbs have long been used as food and in oriental medicine. However, the usage and value of cut lily bulbs has not been recognized. A bulb whose yield has been decreased is called a waste bulb, and a large amount of such bulbs is discarded every year. In this study, the functionality of waste bulbs from cut lilies was investigated to explore their potential use as a value-added product. We divided lily bulbs into two groups, one group with six varieties of new bulbs (Medusa, Siberia, Woori Tower, Yelloween, Le Reve, and Morning Star) used for cultivation and the other group with six varieties of waste bulbs (Medusa, Siberia, Woori Tower, Yelloween, Sorbonne, and Sheila). Physiological activities (${\alpha},{\alpha}$-diphenyl-${\beta}$-picrylhydrazyl: DPPH) and 3-ethlbenzthiazolne-6-sulfonic acid (ABTS) radical scavenging capability and tyrosinase inhibiting activity), the amount of total as well as eight individual phenolic compounds (chlorogenic acid, epicatechin, rutin hydrate, p-coumaric acid, kaempferol 3-O-${\beta}$-rutinoside, phloridzin dihydrate, myricetin, and quercetin), and total flavonoid content were measured in the bulbs by high performance liquid chromatography. We detected high amounts of total phenol and total flavonoid as well as high DPPH and ABTS radical scavenging ability. More tyrosinase inhibiting activity was detected in the new bulbs than in the waste bulbs. However, both the new and waste bulbs showed a higher inhibitory activity than the standard (100 ppm ascorbic acid). Although the content of phenolic compounds differed among varieties, under the conditions of the experiment, the most abundant phenolics were epicatechins, followed by chlorogenic acid, and rutins. Overall, the waste bulbs had a higher content of these compounds than the new bulbs. Based on these results, we concluded that bulbs from cut lilies could be used as functional foods in the future and farmers could expect economic gain from the hitherto neglected waste bulbs.