• Food Science and Preservation
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• v.21 no.4
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• pp.520-528
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• 2014

The purpose of this study was to evaluated a phthalate, heavy metal contents and physicochemical quality properties in korean mudflat solar salt and foreign salts. DEHP in mudflat solar salt (MSS) was detected a low level (9.00~669.89 ppb), but it was shown a high level excess to 1.5 ppm criteria in the foreign solar salt (FSS) 5 type (3,440.64, 3,266.56, 2,189.65, 4,010.69, 4,554.20 ppb) and foreign large solar salt (FLSS) 1 type (1,983.27 ppb). Also, DEHP in FSS 2 type (930.15, 1,310.07 ppb) and FLSS 1 type (924.92 ppb) was detected a high level not excess to criteria. No detected DMP, DEP, DIBP, DBP, DAP, BBP, DCHP and DEHA contents in MSS and foreign salt (FS). Na ion was shown a significantly higher level (p<0.05) in FS (407,345.87~426,612.14 ppm) than in MSS (363,633.98 ppm), but it was shown a high level in Mg (p<0.01), K (p<0.05), Ca ion (p<0.05) of FSS compared to foreign refined salt (FRS). Cl ion (532,727.07 ppm) of MSS was the most low level (p<0.001) compared to FS, but it was shown a high level (p<0.001) in Br ion (625.07 ppm). $SO_4$ ion was not shown a significant difference in DS and FS. It was display a high level in Mn of MSS, and Al, Fe of FLSS. Heavy metal contents (As, Cd, Pb and Hg) in MSS and FS was not significant difference, it was safety level as edible salt.

• Korean Journal of Medicinal Crop Science
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• v.1 no.2
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• pp.178-183
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• 1993

This study was carried out to investigate the contents of ash and inorganicelements in the herbaceous paeony roots collected from the markets of 9 regions in Korea. The contents of paeoniflorin ranged from 2.14% to 3.7%, and the average was 2.87%. The mean contents of ash was 4.2% and acid insoluble ash content was 0.55%. Total nitrogen of herbaceous paeony roots was 0.7%, phosphorus 0.69%, potassium 0.73%, calcium monoxide 1.02% and ferric oxide 82.15ppm respectively. The content of zinc ranged from 19.80ppm to 103.02ppm and the average was 34.59ppm ; this value showed some differences than other elements were, and the mean content of magnesium was 0.25%. The cadmium content showed 0.31ppm copper 4.95ppm, and plumbum 20.47ppm respectively. As above results, we could say that there was no health problems with local products, if we use a the herb medicine.

• Korean Journal of Remote Sensing
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• v.14 no.1
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• pp.53-68
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• 1998

Observation of hydrometeors' behavior in the atmosphere is important to understand weather and climate. By conventional observations, we can get the distribution of water vapor at limited number of points on the earth. In this study, the precipitable water has been estimated from the split window channel data on GMS-5 based upon the technique developed by Chesters et al.(1983). To retrieve the precipitable water, water vapor absorption parameter depending on filter function of sensor has been derived using the regression analysis between the split window channel data and the radiosonde data observed at Osan, Pohang, Kwangiu and Cheju staions for 4 months. The air temperature of 700 hPa from the Global Spectral Model of Korea Meteorological Administration (GSM/KMA) has been used as mean air temperature for single layer radiation model. The retrieved precipitable water for the period from August 1996 through December 1996 are compared to radiosonde data. It is shown that the root mean square differences between radiosonde observations and the GMS-5 retrievals range from 0.65 g/$cm^2$ to 1.09 g/$cm^2$ with correlation coefficient of 0.46 on hourly basis. The monthly distribution of precipitable water from GMS-5 shows almost good representation in large scale. Precipitable water is produced 4 times a day at Korea Meteorological Administration in the form of grid point data with 0.5 degree lat./lon. resolution. The data can be used in the objective analysis for numerical weather prediction and to increase the accuracy of humidity analysis especially under clear sky condition. And also, the data is a useful complement to existing data set for climatological research. But it is necessary to get higher correlation between radiosonde observations and the GMS-5 retrievals for operational applications.

• Anatomy & Biological Anthropology
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• v.31 no.4
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• pp.133-142
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• 2018

3D histology is a imaging system for the 3D structural information of cells or tissues. The synchrotron radiation propagation phase contrast micro-CT has been used in 3D imaging methods. However, the simple phase contrast micro-CT did not give sufficient micro-structural information when the specimen contains soft elements, as is the case with many biomedical tissue samples. The purpose of this study is to develop a new technique to enhance the phase contrast effect for soft tissue imaging. Experiments were performed at the imaging beam lines of Pohang Accelerator Laboratory (PAL). The biomedical tissue samples under frozen state was mounted on a computer-controlled precision stage and rotated in $0.18^{\circ}$ increments through $180^{\circ}$. An X-ray shadow of a specimen was converted into a visual image on the surface of a CdWO4 scintillator that was magnified using a microscopic objective lens(X5 or X20) before being captured with a digital CCD camera. 3-dimensional volume images of the specimen were obtained by applying a filtered back-projection algorithm to the projection images using a software package OCTOPUS. Surface reconstruction and volume segmentation and rendering were performed were performed using Amira software. In this study, We found that synchrotron phase contrast imaging of frozen tissue samples has higher contrast power for soft tissue than that of non-frozen samples. In conclusion, synchrotron radiation propagation phase contrast cryo-microCT imaging offers a promising tool for non-destructive high resolution 3D histology.

• The Korean Journal of Archival Studies
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• no.1
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• pp.23-76
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• 2000

In this paper, I examined what have been researched and determined about preservation strategy and selection of preservation media in the western archival community. Archivists have primarily been concerned with 'preservation' and 'use' of archival materials worth of being preserved permanently. In the new information era, preservation and use of archival materials were faced with new challenge. Life expectancy of paper records was shortened due to acidification and brittleness of the modem papers. Also emergence of information technology affects the traditional way of preservation and use of archival materials. User expectations are becoming so high technology-oriented and so complicated as to make archivists act like information managers using computer technology rather than traditional archival handicraft. Preservation strategy plays an important role in archival management as well as information management. For a cost-effective management of archives and archival institutions, preservation strategy is a must. The preservation strategy encompasses all aspects of archival preservation process and practices, from selection of archives, appraisal, inventorying, arrangement, description, conservation, microfilming or digitization, archival buildings, and access service. Those archival functions should be considered in their relations to each other to ensure proper preservation of archival materials. In the integrated preservation strategy, 'preservation' and 'use' should be combined and fulfilled without sacrificing the other. Preservation strategy planning is essential to determine the policies of archives to preserve their holdings safe and provide people with a maximum access in most effective ways. Preservation microfilming is to ensure permanent preservation of information held in important archival materials. To do this, a detailed standardization has been developed to guarantee the permanence of microfilm as well as its product quality. Silver gelatin film can last up to 500 years in the optimum storage environment and the most viable option for permanent preservation media. ISO and ANIS developed such standards for the quality of microfilms and microfilming technology. Preservation microfilming guidelines was also developed to ensure effective archival management and picture quality of microfilms. It is essential to assess the need of preservation microfilming. Limit in resources always put a restraint on preservation management. Appraisal (and selection) of what to be preserved was the most important part of preservation microfilming. In addition, microfilms with standard quality can be scanned to produce quality digital images for instant use through internet. As information technology develops, archivists began to utilize information technology to make preservation easier and more economical, and to promote use of archival materials through computer communication network. Digitization was introduced to provide easy and universal access to unique archives, and its large capacity of preserving archival data seems very promising. However, digitization, i.e., transferring images of records to electronic codes, still, needs to be standardized. Digitized data are electronic records, and st present electronic records are very unstable and not to be preserved permanently. Digital media including optical disks materials have not been proved as reliable media for permanent preservation. Due to their chemical coating and physical character using light, they are not stable and can be preserved at best 100 years in the optimum storage environment. Most CD-R can last only 20 years. Furthermore, obsolescence of hardware and software makes hard to reproduce digital images made from earlier versions. Even if when reformatting is possible, the cost of refreshing or upgrading of digital images is very expensive and the very process has to be done at least every five to ten years. No standard for this obsolescence of hardware and software has come into being yet. In short, digital permanence is not a fact, but remains to be uncertain possibility. Archivists must consider in their preservation planning both risk of introducing new technology and promising possibility of new technology at the same time. In planning digitization of historical materials, archivists should incorporate planning for maintaining digitized images and reformatting them in the coming generations of new applications. Without the comprehensive planning, future use of the expensive digital images will become unavailable. And that is a loss of information, and a final failure of both 'preservation' and 'use' of archival materials. As peter Adelstein said, it is wise to be conservative when considerations of conservations are involved.

• Journal of Life Science
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• v.28 no.11
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• pp.1339-1346
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• 2018

In Korea, edible mushrooms are produced largely on commercial artificial media, so the annual production of spent mushroom substrate (SMS), as a by-product of the mushroom industry, is estimated at over 200 million tons. This SMS is assumed to contain abundant fungal mycelia and pre-fruiting bodies, as well as various nutritive and bioactive compounds that are presently discarded. This study examined the physico-chemical, nutritional, and enzymatic characteristics of uninoculated sterilized medium (USM) and SMS of shiitake mushrooms with the aim of developing a high-value added product from SMS. The contents of crude protein, crude lipid, and ash were higher after the third SMS harvest ($SMS-A-3^{rd}$) than in USM or $SMS-A-1^{st}$. The contents of Ca, Mg, and P in $SMS-A-3^{rd}$ were 2.95, 2.35, and 2.1-fold higher compared than in USM. No As or Cd was detected in USM or SMS. The pH, Brix, and acidity were 4.6, 20.0, and 1.4, respectively in $SMS-A-3^{rd}$, but 5.6, 6.0, and 0.0, respectively, in USM. These results suggest a highly active production of soluble components and organic acids in $SMS-A-3^{rd}$. The distinct color differences noted for USM, $SMS-A-1^{st}$, and $SMS-A-3^{rd}$ could be used as a mycelial growth indicator. Enzyme activity assays using the APIZYM system showed that SMS is a potent source of hydrolysis-related enzymes, especially esterase (C4) and ${\beta}$-glucuronidase. Our results suggested that the SMS of shiitake has a high potential for use in environmental, agricultural, and stock-breeding industries, for example, as active ingredients for sewage treatment, waste-polymer degradation, and feed additives.

• Journal of Food Hygiene and Safety
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• v.36 no.3
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• pp.248-256
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• 2021

A total of 120 samples corresponding to 12 categories of dried processed fishery products distributed in Gyeonggi-do were examined for radioactivity contamination (¹³¹I, ¹³⁴Cs, ¹³⁷Cs) and heavy metals (lead, cadmium, arsenic, and mercury). One natural radioactive material, ⁴⁰K, was detected in all products, while the artificial radioactive materials ¹³¹I, ¹³⁴Cs and ¹³⁷Cs were not detected at above MDA (minimum detectable activity) values. The detection ranges of heavy metals converted by biological basis were found as follows: Pb (N.D.-0.332 mg/kg), Cd (N.D.-2.941 mg/kg), As (0.371-15.007 mg/kg), Hg (0.0005-0.0621 mg/kg). Heavy metals were detected within standard levels when there was an acceptable standard, but the arsenic content was high in most products, although none of the products had a permitted level of arsenic. In the case of dried processed fishery products, there are products that are consumed by restoring moisture to its original state, but there are also many products that are consumed directly in the dry state, so it will be necessary to set permitted levels for heavy metals considering this situation in the future. In addition, Japan has decided to release contaminated water from the Fukushima nuclear power plant into the ocean, so there is high public concern about radioactivity contamination of food, including fishery products. Therefore, continuous monitoring of various food items will be necessary to ease consumers' anxiety.

• Journal of Food Hygiene and Safety
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• v.37 no.3
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• pp.166-172
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• 2022

This study evaluated the migrant and residue tests of lead (Pb), cadmium (Cd), nickel (Ni), arsenic (As), and antimony (Sb) in 70 tumbler samples. The migration levels of hazardous metals in all the samples were within the migration limits outlined in the Korean standards and specifications for utensils, containers, and packages. Moreover, in all the tumbler samples, only Ni was detected in 0.5% citric acid solution of a food stimulant. The maximum level of Ni 0.0144 mg/L was 14.4% of the migrant specification (not more than 0.1 mg/L), which was relatively safe. The 0.5% citric acid solution was eluted at 4℃, 70℃, and 100℃ for 30 min, and only Ni was detected while testing for migration levels according to the temperature variations; all temperature conditions conformed to the standards. The level of Ni migration increased significantly with increasing migration temperature. Regarding the residue level outside the paint-coated tumbler samples, the Pb level was found to range from N.D. to 20638.1323 mg/kg. The risk of Ni was further estimated to be at a safe level of 0.00 to 0.01% compared to the %TDI as a result.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.1
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• pp.1-25
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• 1982

Limnological study on the physico-chemical properties and biological characteristics of the Lake Ok-Jeong was made from May 1980 to August 1981. For the planktonic organisms in the lake, species composition, seasonal change and diurnal vertical distribution based on the monthly plankton samples were investigated in conjunction with the physico-chemical properties of the body of water in the lake. Analysis of temperature revealed that there were three distinctive periods in terms of vertical mixing of the water column. During the winter season (November-March) the vertical column was completely mixed, and no temperature gradient was observed. In February temperature of the whole column from the surface to the bottom was $3.5^{\circ}C$, which was the minimum value. With seasonal warming in spring, surface water forms thermoclines at the depth of 0-10 m from April to June. In summer (July-October) the surface mixing layer was deepened to form a strong thermocline at the depth of 15-25 m. At this time surface water reached up to $28.2^{\circ}C$ in August, accompanied by a significant increase in the temperature of bottom layer. Maximum bottom temperature was $r5^{\circ}C$ which occurred in September, thus showing that this lake keeps a significant turbulence Aehgh the hypolimnial layer. As autumn cooling proceeded summer stratification was destroyed from the end of October resulting in vertical mixing. In surface layer seasonal changes of pH were within the range from 6.8 in January to 9.0 in guutuost. Thighest value observed in August was mainly due to the photosynthetic activity of the phytoplankton. In the surface layer DO was always saturated throughout the year. Particularly in winter (January-April) the surface water was oversaturated (Max. 15.2 ppm in March). Vertical variation of DO was not remarkable, and bottom water was fairly well oxygenated. Transparency was closely related to the phytoplankton bloom. The highest value (4.6 m) was recorded in February when the primary production was low. During summer transparency decreased hand the lowest value (0.9 m) was recorded in August. It is mainly due to the dense blooming of gnabaena spiroides var. crassa in the surface layer. A. The amount of inorganic matters (Ca, Mg, Fe) reveals that Lake Ok-Jeong is classified as a soft-water lake. The amount of Cl, $NO_3-N$ and COD in 1981 was slightly higher than those in 1980. Heavy metals (Zn, Cu, Pb, Cd and Hg) were not detectable throughout the study period. During the study period 107 species of planktonic organisms representing 72 genera were identified. They include 12 species of Cyanophyta, 19 species of Bacillariophyta, 23 species of Chlorophyta, 14 species of Protozoa, 29 species of Rotifera, 4 species of Cladocera and 6 species of Copepoda. Bimodal blooming of phytoplankton was observed. A large blooming ($1,504\times10^3\;cells/l$ in October) was observed from July to October; a small blooming was present ($236\times10^3\;cells/l$ in February) from January to April. The dominant phytoplankton species include Melosira granulata, Anabaena spiroides, Asterionella gracillima and Microcystis aeruginota, which were classified into three seasonal groups : summer group, winter group and the whole year group. The sumner group includes Melosira granulate and Anabaena spiroides ; the winter group includes Asterionella gracillima and Synedra acus, S. ulna: the whole year group includes Microtystis aeruginosa and Ankistrodesmus falcatus. It is noted that M. granulate tends to aggregate in the bottom layer from January to August. The dominant zooplankters were Thermocpclops taihokuensis, Difflugia corona, Bosmina longirostris, Bosminopsis deitersi, Keratelle quadrata and Asplanchna priodonta. A single peak of zooplankton growth was observed and maximum zooplankton occurrence was present in July. Diurnal vertical migration was revealed by Microcystis aeruginosa, M. incerta, Anabaena spiroides, Melosira granulata, and Bosmina longirostris. Of these, M. granulata descends to the bottom and forms aggregation after sunset. B. longirostris shows fairly typical nocturnal migration. They ascends to the surface after sunset and disperse in the whole water column during night. Foully one species of fish representing 31 genera were collected. Of these 13 species including Pseudoperilnmpus uyekii and Coreoleuciscus splendidus were indigenous species of Korean inland waters. The indicator species of water quality determination include Microcystis aeruginosa, Melosira granulata, Asterionelta gracillima, Brachionus calyciflorus, Filinia longiseta, Conochiloides natans, Asplanchna priodonta, Difflugia corona, Eudorina elegans, Ceratium hirundinella, Bosmina longirostris, Bosminopsis deitersi, Heliodiaptomus kikuchii and Thermocyclops taihokuensis. These species have been known the indicator groups which are commonly found in the eutrophic lakes. Based on these planktonic indicators Lake Ok-Jeong can be classified into an eutrophic lake.

• Korean Journal of Environmental Agriculture
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• v.18 no.2
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• pp.126-134
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• 1999

To provide the basic information for the water improvement and control of water resource in Nakdong river districts, the physico-chemical characteristics of water in four main streams and three branch streams of the river were investigated through 36 times totally, one time per each month from January in 1995 to November in 1997. The pH values of each sites in main or branch stream of Nakdong river was pH $6.3{\sim}9.3$ range, pH range of Jukpo and Namji area at spring and fall was almost over pH 8.5, which was exceeded the water quality standard for agriculture. DO values of Nakdong river was almost $8.0{\sim}13mg/l$, except for Kangchang area in downstream of Kumho river. BOD values in Dasa area where was prior to mixing of Kumho river was $1.5{\sim}4.8mg/l$, which was under the water quality standard for agriculture(8mg/l), but BOD values followed mixing of Kumho river was over the permit standard of agricultural water as $3.8{\sim}8.9mg/l$ in Koryung, $3.4{\sim}8.4mg/l$ in Jukpo and $3.3{\sim}7.8mg/l$ in Namji according to time or season. Especially, BOD values at Gangchang area in Kumho river were $7.6{\sim}18.5mg/l$, which was over the water quality standard for agriculture and so Kumho river was a main pollutant: source of Nakdong river. COD values of main stream of Nakdong river was over the permit standard of agriculture(8mg/l) as $5.2{\sim}13.5mg/l$ in Koryvng, $5.0{\sim}12.7mg/l$ in Jukpo and $5.0{\sim}12.2mg/l$ in Namji according to time or season. And COD values was much high rather than BOD values and its gap of concentration was increased along with downstream. $NH_4-N$ of main stream of Nakdong river followed mixing of Kumho river($0.5{\sim}13.1mg/l$) was the highest affected in Koryung($0.18{\sim}5.0mg/l$) and detected much more in winter than in summer. T-N in Koryung($4.96{\sim}12.06mg/l$) followed mixing of Kumho river was significantly high rather than $2.86{\sim}4.86mg/l$ in Dasa, $4.20{\sim}8.20mg/l$ in Jukpo and $3.18{\sim}8.64mg/l$ in Namji, which was almost over the permit standard of agricultural water(1.0mg/l). T-P in Koryung($0.10{\sim}0.58mg/l$) also was significantly high rather than those $0.07{\sim}0.36mg/l$ in Jukpo and $0.08{\sim}0.4mg/l$ in Namji as over the standard of agricultural water(0.1mg/l). The concentration of T-N or T-P in Nakdong districts was trended of increasing in every year.