• Journal of Conservation Science
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• v.29 no.4
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• pp.297-309
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• 2013

Iron objects become corroded at fast speed from the moment when they are excavated, so it is needed to control corrosion through processes of conservation treatment. However, re-corrosion mostly takes place in excavate iron objects, although they have already gone through the process of conservation treatment, and it is more difficult to carry out the second conservation treatment of re-corroded excavated iron objects than the first conservation treatment, and it requires a longer period of time to treat them as well. In this study, aims to discover factors of re-corrosion by scientifically analyzing corrosion products generated during the process of storage after the process of conservation treatment. The finished on conservation treatment of the iron artifacts, which were unearthed from three ancient site in Gyeongju by using the same conservation method between 2002 and 2009, re-corrosion condition observed on the packaging-iron artifacts. Focused on 9 target forged iron artifacts among them, this study analyzed the physical changes by mass measurement, naked-eye and microscopic observations and the chemical changes by SEM-EDS, XRD, IC and ICP analysis. The results show that the yellowish brown corrosion products formed on the facing surface of part dropped from the artifacts had different associated forms but acicular shape. In addition, the acicular shape became clearer as the color changed from red to yellowish brown. According to the process when the conservation treatment was completed, the mass of the artifacts increased in proportion to the corrosion products and the chloride ion ($Cl^-$) concentration had a tendency to increase relatively. ${\beta}$-FeOOH (akaganeite) was confirmed in the XRD analysis for the corrosion products of all the collected samples. As a result of ICP analysis, $Na^+$ and $Ca^{2+}$ components were confirmed.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.2
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• pp.55-63
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• 2009

This study was performed to evaluate the heavy metal contents in various packaging board. Domestic and foreign OCC (old corrugated containers) and old duplex boards were used as raw materials. Tests were made for the printed and unprinted parts of the sample. Heavy metal contents of old food packaging boards made from virgin pulp fibers were also evaluated. The contents of heavy metals including lead (Pb), cadmium (Cd), barium (Ba), arsenic (As), antimony (Sb), selenium (Se), and mercury (Hg) were determined using ICP-AES (Inductively Coupled Plasma - Atomic Emission Spectrometer), and CV-AAS (Cold vapor-atomic absorption spectrometer) after digesting the samples in a microwave oven. The contents of heavy metals contained in domestic packaging board were higher than those in overseas samples, and OCC showed higher contents of heavy metals than old duplex boards. Printed parts gave greater heavy metal contents than unprinted parts. Results indicate that recycling of paper and paperboard products increases the heavy metal contamination of the paper packaging products and this derives mostly from the heavy metals contained in printing inks. Recycling processes that decrease heavy metals in recycled fibers and new printing inks that contains less heavy metals should be developed to solve the problem associated with the heavy metals in packaging paper products.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.4
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• pp.461-469
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• 2013

This research is performed to investigate the changes in the physicochemical properties and microbial growths of seasoned anchovies with various packaging materials (PET/CPP : polyethylene terephthalate/cast polypropylene, PET/EVOH : polyethylene terephthalate/ethylene-vinyl alcohol, PET/AL/LDPE: polyethylene terephthalate/aluminum/low density polyethylene), which are stored at various temperatures (25, 35, $45^{\circ}C$) for 60 days. Generally, it is being observed that changes in physicochemical properties (i.e., moisture content, color, brown intensity, TBA value, TMA, VBN etc) of seasoned anchovies are significant when stored at higher temperatures. Particularly, the packaging materials are found to influence substantially on the physicochemical properties of seasoned anchovies. With packaging materials of high oxygen transmission rates and moisture vapor transmission rates (i.e., PET/CPP), the changes in physicochemical properties of seasoned anchovies are significant, while being low with low oxygen transmission rates and low moisture vapor transmission rates (i.e., PET/EVOH). In addition, results of microbial growths in seasoned anchovies show that significant increases in total aerobic bacteria counts (about 100-fold after 60 day of storage) are observed in samples with packaging materials of high oxygen transmission rates and moisture vapor transmission rates (i.e, PET/CPP), while with only small increases for samples of low oxygen transmission rates and low moisture vapor transmission rates (i.e., PET/EVOH). Based on the changes in the physicochemical properties and results of microbial growths, it is being concluded that PET/EVOH film is suitable for the packaging of seasoned anchovies.

• Korean Journal of Food Science and Technology
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• v.51 no.6
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• pp.524-530
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• 2019

Kelp (Saccharina japonica) contains various bioactive compounds, including vitamins, minerals (especially iodine and potassium), alginic acid, fucoxanthin, and various antioxidants. Kelp is mainly used as a dried product. The purpose of this study was to investigate the stabilities of antioxidant capacities and fucoxanthin of kelp by different conventional drying conditions including hot air drying at 70℃ and natural drying methods. Fucoxanthin, total phenolic contents, and total antioxidant capacity by ABTS, DPPH, and FRAP assays were significantly decreased after 5 to 10 h of hot air drying at 70℃. The assay values were also significantly decreased by 50% after 2 days of drying due to ultraviolet exposure. The findings demonstrate that heat and ultraviolet exposure during drying of kelp could affect the degradation of bioactive compounds, especially fucoxanthin and polyphenols. Optimal conditions should be considered during kelp drying and storage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.7 no.1
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• pp.117-121
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• 1969

Germination and field test were made with the spring barley sprouted with gibberellin solution of 5 levels from 5 to 100 ppm. Temperatures of room for germination were classified as ordinary and low. Results obtained will be summarized as follows: 1. Sprouting with Gibberellin promoted the germination by two days in ordinary and three days in low temperature without reducing the germination rate. 2. The higher concentration of gibberellin showed the more promotion of growth in early stage. 3. No retardation of root-growth was found by gibberellin sprouting. 4. No promoting effects to germination by gibberellin sprouting was found in field tests. In high concentration, percentage of germination, number of spike and grain yields reduced remarkably. 5. More remarkable tendency of weak growth and longer duration of recovery were found in the higher concentration of gibberellin, but all plots recovered from weak growth at middle stage of plant growth. 6. In gibberellin concentration of 5 to 10 ppm, retardation of germination, weakness of early growth and reducing of spike number were not remarkable while length of spike and 1000 grain weight were increased. Therefore grain yields showed increasing tendency. 7. Promoting the germination may be expected but hastening of heading and maturing may not be available by gibberellin treatment in sprouting.

• Korean Journal Plant Pathology
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• v.13 no.3
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• pp.191-193
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• 1997

A new disease of arrowhead (Sagittaria trifolia L.)caused by Plectosporium tabacinum was observed at Yusung area in Korea. Infection occurred on the petioles, leaves, and seeds of young and old arrowhead plants. Small and brown spots developed on the infected areas initially, which later coalesced to form large dead areas resulting in the complete blight of the host plant. Inoculation of arrowhead seedlings by conidial suspension induced typical disease symptoms found in naturally infected plants. The new name for the disease 'arrowhead blight' is suggested. The pathogenic fungus was identified as Plectosporium tabacinum and its morphological and cultural characteristics are described.

• Food Science and Preservation
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• v.2 no.2
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• pp.277-284
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• 1995

To study the shelf-life of cut cabbage kimchi, we examined the several quality characteristics of cabbage kimchi under various storage temperatures and packing materials. The pH of kimchi extracts were decreased to 4.0 in the condition of storage at 8$^{\circ}C$ during 6 days, at 4$^{\circ}C$ during 18days, 0$^{\circ}C$ during 42 days. The increase patterns of the organic acid were reverse to the changes of pH under the all conditions. The contents of reducing sugar were continuously decreased at 8$^{\circ}C$ , but increased gradually at 0$^{\circ}C$ and 4$^{\circ}C$ storage conditions. The contents of vitamine C were decreased at the early storage but increased to optimum ripening stage of pH 4.2-4.4 and after decreased continuously. The total bacterial cell counts of cabbage kimchi were increased suddenly at the early storage and after decreased gradually. And at the higher storage temperature, the more lactic acid bacteria were. On the results of sensory evaluation of cabbage kimchi at marketable shelf-life, sour taste and sour smell were significant under all experimental conditions by Duncan's multiple range test. On the above all results, we concluded that the marketable shelf-life of cut cabbage kimchi were 42 days, 19 days, 6 days at 0$^{\circ}C$, 4$^{\circ}C$, 8$^{\circ}C$ storage condition respectively.

• Korean journal of applied entomology
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• v.22 no.3 s.56
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• pp.181-185
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• 1983

Ditylenchus destructor Thorne 1945 was found to be the causal organism of the new root rot disease of Panax ginseng, which occurred extensively in Dongseong area of Cheolweon-gun, Gangweon Province, Korea in 1982. Thirty-six percent of the investigated fields was damaged due to the potato rot nematode. Infected roots showed brown discoloration of cortex and suberization outside the cambium. Cortex of the severly infected roots became sponge-like in texture and cavity was produced in the central portion of the root. Only the severely infected ginseng plants exhibited sympotoms of sudden wilting of leaves. The number of potato rot nematode in such field soils was $8.5\~222/30g$ soil, while there was no such symptoms on leaves if the number was less than 7.

• Journal of the Korean Geosynthetics Society
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• v.17 no.3
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• pp.47-55
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• 2018

Recently, increasing number of urban ground subsidence occurrences has been identified. This situation is mainly due to the increased number of underground cavities. This study is intended to develop the method that prevents ground settlement caused by deteriorated or damaged sewers, which are the main cause of land subsidence. To that end, GPR exploration was conducted using CCTV monitoring of deteriorated sewer at the location with high settlement potential. Through such CCTV monitoring and GPR investigation, abnormal ground behavior was monitored at the site where sewer was damaged, joint was cracked and soil was deposited. According to site investigation in this study, evaluation method using correlation analysis of CCTV monitoring and GPR investigation results is expected to prevent ground settlement attributable to damaged sewer.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.4
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• pp.931-940
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• 2015

Roller Compacted Concrete Pavement (RCCP), is a type of pavement using compaction roller and asphalt finisher on concrete mixture that contains low amount of water. RCCP strength and durability are greatly affected by compaction level. Quality control is performed by ensuring the degree of compaction at site based on dry density. In the field, Modified Proctor Test is used in order to obtain optimum dry density. However, there is no clear compaction curve analysis criteria of Modified Proctor Test for RCCP. In this study, compaction curve built by three samples of Modified Proctor Test was produced and it was used to compare with compaction curve contented lower number of samples (one and two samples) in order to analyze their reliability. Thus, a conclusion was drawn from the results; by comparing to the result from Modified Proctor Test of three samples, the use of two samples represented result with only 0.5% of error which means the reliability is 99.5%.