• Korean Journal of Soil Science and Fertilizer
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• v.50 no.5
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• pp.462-471
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• 2017

A more efficient use of nutrients from organic sources can benefit both farmers and water quality in agriculture. In this paper we reviewed information related to the regulations and guidelines of a swine liquid fertilizer to propose an establishment scheme for the official standards of swine manure slurry as a liquid fertilizer for organic farming. According to the law of establishment and designation of official standard of fertilizers, the liquid fertilizer made with pig liquid manure belongs to the byproduct fertilizer as of one of organic fertilizer. However, the official standards for byproduct fertilizers including the liquid fertilizer set by the Rural Development Administration (RDA), especially for a liquid swine manure fertilizer, should be revised to meet the goals of laws pursuing the environmentally sound agriculture, especially for organic farming because the terms and relevant standards need additional specific standards alike the standards such as impurities and parameter for declaration in EU. Therefore, it is suggested that official standards for byproduct fertilizers should be revised with respect to nutrient, salt content as of SAR and Na content instead of NaCl. Also we need to develop the maximum limit of heavy metals in soil to which the liquid fertilizer can be applied, as well as application rate depending on EC of the liquid fertilizer.

• Korean Journal of Organic Agriculture
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• v.9 no.2
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• pp.1-23
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• 2001

It was supposed that CSA could be one of the best way to promote the movement of organic agriculture since there is little reliability on the organically grown food by consumer. In the replies submitted to a questionnaire to farmer and consumer, both group responded that the need of development of cultivation technique for organic farming and the permitted substances for organic farming and production. Both of them also replied that it is necessary to establish the lectures or division/department for organic agriculture in the agricultural education program of University. Their response to CSA was so much positive that they are willing to participate the CSA farm as a active CSA farmers or consumers. Based on the evaluation of questionnaire survey, it was suggested to do the utmost efforts that farmer preferentially practice an organic farming , md consumer consciously buy an organic food to protect an ecosystem and environment pollution.

• Korean Journal of Ecology and Environment
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• v.44 no.4
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• pp.358-363
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• 2011

This study investigated the characteristics of natural organic matter(NOM) with tXAD resin and FT-IR in the Yeongsan river system of Gwangju region. NOM fractionation by XAD 8/4 resins was used to classify hydrophobic and hydrophilic substances. FTIR was applied to classify functional groups in the structure of NOM. In the XAD investigation, most of the four site-samples were mainly hydrophilic substances. In March, hydrophobic substances were dominant in the Gwangju 1 site (GJ-1), while hydrophilic substances were dominant for the other sites. In May, samples of all four sites were hydrophilic with a vigorous activity of microorganism due to increasing temperatures. The October results were very similar with those from March. In the FT-IR investigation, most of the broad and large peaks were assigned to the aliphatic group, particularly the OH group, C-H, $C-H_2$, $C-H_3$, and C-O alcohol group. All were related to hydrophilic substances. Other peaks showed the aromatic group, particularly the C=O (Ketone) Group. As a result, there is an identification of NOM in the Yeongsan river system composing mainly of hydrophilic substances and functional groups (OH, C-H etc.) of the aliphatic compound.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.4
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• pp.71-81
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• 2019

This research was conducted to improve availability of agricultural by-products, national natural resources that could be used as fertilizer source, by estimating the amount of production and collecting main contents of fertilizer substances from previous studies and data, in order to be used as basic data to investigate national resources that could be used as alternatives for imported oil-cakes in the future. Conversion factor was used to estimate annual production of agricultural by-products for main 34 crop types in 2018. For total agricultural by-products, rice straws accounted at 50.3% for the highest proportion, followed by 8.7% of rice husks, showing that by-products from rice harvest accounted at 59.0% for all by-products. Further, there were listed the contents of fertilizer substances (nitrogen, phosphoric acid, potash) in 40 types of by-products from agricultural areas. The average contents of nitrogen, phosphoric acid, and potash in agricultural by-products were 1.43%, 0.59%, and 1.90%, respectively. As a result of estimating the annual nitrogen supply amount from 26 agricultural by-products in 2018, it was found that it could supply 44,911 tons of nitrogen. The investigated by-products contained fertilizer substances such as nitrogen, phosphoric acid, and potash, but the contents were lower compared to castor oil-cake used as main component of organic fertilizer. Therefore, resource management plan needs to be established for efficient use of by-products because time, location, and nutrient content of agricultural by-product production were extremely different. Research on fertilizer and manure using agricultural by-products need to be conducted to develop and distribute alternatives for imported oil-cakes.

• The Korean Journal of Physiology
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• v.2 no.1
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• pp.59-71
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• 1968

The uptake of phenolsulfonphthalein (PSP) and of paraaminohippuric acid (PAH) by cortical slices of the rabbit kidney was investigated while varying the composition of medium. The overall uptake of these substances displayed typical active transport characteristics and was significantly enhanced in presence of acetate. When the phosphate buffer was used the optimal pH was 7.4 for both substances. However, when the tris-buffer was used the optimal pH was 7.4 for PSP and 8.3 for PAH. Removal of $Na^+$ from the medium resulted in a significant reduction in the uptake. Similar results, though lesser in magnitude, were obtained when either $K^+\;or\;Ca^{++}$ was removed from the medium. However, there was no additive effect when $K^+\;and/or\;Ca^{++}$ were additionally removed from the $Na^+-free$ medium. The presence of ${NH_4}^+$ greatly reduced while $Li^+\;and\;Mg^{++}$ moderately reduced the uptake of both substances. However, choline had no effect. In substrate-leached slices, acetate greatly enhance the uptake of organic acids; but this action was not demonstrable in absence of $Na^+,\;K^+\;or\;Ca^{++}$.

• The Korean Journal of Food And Nutrition
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• v.34 no.1
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• pp.132-136
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• 2021

The purpose of this study is to measure the levels of eluted and dissolved CO2, and CO, volatile organic substances and radiation composition of Cheongsong mineral water which were collected from November 2019 to July 2020 during the autumn, spring, and summer seasons at collection points located in the upper, middle and lower spring waters. Data of the upper, middle and lower spring waters include the following: the amount of eluted water (average value±standard deviation, mL/min) was 30.07±0.52, 15.03±0.16, 23.73±0.42, and the amount of CO2 gas was 1,000 ppm or more. In addition, there was no detection of CO or total volatile organic substances (TVOC) and the radiation dose was 0.08 to 0.13. μSv/h. A blank test value of 0.08 to 0.10 μSv/h, when compared with the median value, showed a high value of 0.02 μSv/h, and the uranium test results provided by the Cheongsong-gun Office were 0.0118 mg/L (date 2019.06.18) and 0.0091 mg/L (date 2020.06.04.) respectively, which was less than the permission limit of 0.03 mg/L. However, it is believed that further research using more precise devices is needed in order to guarantee the safety and health of the water.

• Ocean and Polar Research
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• v.45 no.3
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• pp.113-123
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• 2023

Humic substances are refractory organic compounds that are relatively low in biological activity but known to stimulate phytoplankton growth in estuarine and marine environments. The effect of humic substances on phytoplankton growth was investigated in the seawater zone of the Yeongsan River estuary where an episodic anthropogenic freshwater is discharged, affecting its water properties directly. Water samples and data of water properties were collected at three stations (Sts. A-C) along the channel of the seawater zone in February, May, August and November, 2009. The collected water samples were incubated after humic acids (HA) were added in mesocosm experiments. Phytoplankton (chlorophyll-a) were fractionated into net- (> 20 ㎛) and nano-size (< 20 ㎛) to examine the response of phytoplankton according to size. Their response to HA treatment was assessed by repeated measures analysis of variance (RM-ANOVA). The experiments showed that phytoplankton biomass (chlorophyll-a) significantly increased after HA were added at the stations near the sea dike. Especially, nano-sized chlorophyll-a concentrations increased significantly throughout the seasons. This indicates that understanding the behavior of refractory organic matters such as humic substances is required to better manage altered estuarine ecosystems including the Yeongsan River estuary which are affected by episodic discharge of freshwater from sea dikes.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.3
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• pp.310-321
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• 2019

Objectives: The purpose of this study was to investigate types and characteristics of chemical substances used in LCD(Liquid crystal display) panel manufacturing process. Methods: The LCD panel manufacturing process is divided into the fabrication(fab) process and module process. The use of chemical substances by process was investigated at four fab processes and two module processes at two domestic TFT-LCD(Thin film transistor-Liquid crystal display) panel manufacturing sites. Results: LCD panels are manufactured through various unit processes such as sputtering, chemical vapor deposition(CVD), etching, and photolithography, and a range of chemicals are used in each process. Metal target materials including copper, aluminum, and indium tin oxide are used in the sputtering process, and gaseous materials such as phosphine, silane, and chlorine are used in CVD and dry etching processes. Inorganic acids such as hydrofluoric acid, nitric acid and sulfuric acid are used in wet etching process, and photoresist and developer are used in photolithography process. Chemical substances for the alignment of liquid crystal, such as polyimides, liquid crystals, and sealants are used in a liquid crystal process. Adhesives and hardeners for adhesion of driver IC and printed circuit board(PCB) to the LCD panel are used in the module process. Conclusions: LCD panels are produced through dozens of unit processes using various types of chemical substances in clean room facilities. Hazardous substances such as organic solvents, reactive gases, irritants, and toxic substances are used in the manufacturing processes, but periodic workplace monitoring applies only to certain chemical substances by law. Therefore, efforts should be made to minimize worker exposure to chemical substances used in LCD panel manufacturing process.

• ALGAE
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• v.31 no.3
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• pp.189-204
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• 2016

Microalgal bioremediation of CO₂, nutrients, endocrine disruptors, hydrocarbons, pesticides, and cyanide compounds have evaluated comprehensively. Microalgal mitigation of nutrients originated from municipal wastewaters, surface waters, and livestock wastewaters has shown great applicability. Algal utilization on secondary and tertiary treatment processes might provide unique and elegant solution on the removing of substances originated from various sources. Microalgae have displayed 3 growth regimes (autotrophic, heterotrophic, and mixotrophic) through which different organic and inorganic substances are being utilized for growth and production of different metabolites. There are still some technology challenges requiring innovative solutions. Strain selection investigation should be directed towards identification of algal that are extremophiles. Understanding and manipulation of metabolic pathways of algae will possible unfold solution to utilization of algae for mitigation of dissolve organic nitrogen in wastewaters.

• Membrane Journal
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• v.6 no.3
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• pp.141-156
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• 1996

For ultra-pure water, the removal of various impirities is required, and the requirement level is rising year by year. To cope with this problem, various removing technologies and system technologies have been developed and the introduction of new materials for the piping, etc. to form the system have been positively made. For the element technologies to be used for ultra-pure water production, their range will be expanded from the technological and economic viewpoints. Therefore, it is absolutely necessary to develop trace analysis evaluation technologies for ultra-pure water. Especially to raise the analytical level of heavy metals and organic substances is important. It is also important to establish individual analysis methods of organic substances. It is expected that the analytical methods will be established and new treating methods will be put to practical use in the near future.