• 한국어류학회지
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• 제31권3호
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• pp.165-171
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• 2019

청계천에서 수량이 감소한 이후 2018년 4월부터 10월까지 복원된 구간에서 조사하였다. 수량이 감소되기 전인 2011년에 비해 수심이 지점에 따라 1~5 cm 정도 감소하였다. 출현한 어종은 총 5과 21종이었고 고유종은 몰개 Squalidus japonicus coreanus와 참갈겨니 Zacco koreanus 2종이었다. 2018년에 출현하지 않은 종은 각시붕어 Rhodeus uyekii, 줄납자루 Acheilognathus yamatsutae, 가시납지리 Acheilognathus gracilis, 누치 Hemibarbus labeo, 버들매치 Abbottina rivularis, 끄리 Opsariichthys uncirostris amurensis, 강준치 Erythroculter erythropterus 등 7종이었다. 수량이 감소한 이후 개체수가 급격히 증가한 어종은 피라미 Zacco platypus였으며 개체수 구성비에 있어 24.9%가 증가하였다. 반면 개체수가 급격히 감소한 어종은 버들치 Rhynchocypris oxycephalus (12.3% 감소)와 참갈겨니(13.2% 감소)이었다. 각 조사 지점에서 우점종은 납자루 Acheilognathus yamatsutae (St. 4)와 피라미(St. 1, 2, 3)이었다. 민감종의 개체수는 34.0%에서 8.5%로 감소하였고 내성종은 50.2%에서 75.5%로 증가하였으나 중간종은 변화가 없었다. 충식성종의 개체수는 48.1%에서 19.2%로 급격히 감소하였고 잡식성은 51.6%에서 80.7%로 급격히 증가하였으며 육식성과 초식성은 큰 차이가 없었다. 우점도지수는 0.62에서 0.76으로 증가, 종다양도 지수는 1.80에서 1.33으로 감소, 종균등도 지수는 0.57에서 0.42로 감소, 종풍부도 지수는 3.02에서 2.90으로 감소하였다.

• Archives of Pharmacal Research
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• 제28권4호
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• pp.493-501
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• 2005

Effect of solvents on physical characteristics and release characteristics of monolithic acetaminophen (APAP) hydroxypropylmethylcellulose (HPMC) matrix granules and tablets were examined. Various types and amounts of solvents were employed for granulation and coating. APAP and other excipients were mixed and were then wet-granulated in a high-speed mixer. The dried granules were then directly compressed and film-coated with low viscosity grade HPMC. As the amount of water increased, the size of granules also increased, showing more spherical and regular shape. However, manufacturing problems such as capping and lamination in tableting occurred when water was used alone as a granulating solvent. The physical properties of HPMC matrix granules were not affected by the batch size. The initial release rate as well as the amount of APAP dissolved had a tendency to decrease as the water level increased. Addition of nonaqueous solvent like ethanol to water resulted in good physical properties of granules. When compared to water/ethanol as a coating solvent, the release rate of film-coated HPMC matrix tablets was more sensitive to the conditions of coating and drying in methylene chloride/ethanol. Most of all, monolithic HPMC matrix tablet when granulated in ethanol/water showed dual release with about $50\%$ drug release immediately within few minutes followed by extended release. It was evident that the type and amount of solvents (mainly water and ethanol) were very important for wet granulation and film-coating of monolithic HPMC matrix tablet, because the plastic deforming and fragmenting properties of material were changed by the different strengths of the different solvents.

• 한국물환경학회지
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• 제27권2호
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• pp.178-187
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• 2011

National water supply, water resources available, the ratio of water supply to total water resources, and the ratio of water supply to available water resources were investigated to find global seawater desalination plant market for 163 nations. Water resources available per capita from 2007 to 2016, population in water scarcity region from 2011 to 2016, and the ratio of water scarcity population to total population were also analyzed for the countries. Annual percentage increase in total municipal drinking water capital expenditure and Annual percentage increase in total industrial water market were analyzed to predict the amount of water supply by use. 76 countries are suffering from water scarcity and 60 countries among the countries have coastal regions. Forty countries were selected by considering the considerable amount and highly increasing trend of water demand by use. Most countries show increasing trend of industrial water and 82 countries have more than 4% annual increasing rate for domestic water expense from 2008 to 2016 among 163 countries. Among the 76 water scarcity countries 16 countries were finally selected by considering expense prediction by use. Middle-east, east asia, pacific ocean, and west europe regions include most selected countries.

• 한국농공학회논문집
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• 제63권4호
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• pp.55-64
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• 2021

The expansion of upland crop cultivation in rice paddy fields is recommended by the Korean government to solve the problem of falling rice price and reduction of rice farmer's income due to oversupply of rice. However, water use efficiency is significantly influenced by the land use change from paddy field to upland. Therefore, this study aimed to evaluate the water budget of soybean grown in using APEX (Agricultural Policy and Environmental eXtender) model. The amount of runoff was measured in a test bed located in Iksan, Jeollabu-do and used to calibrate and validate the simulated runoff by APEX model. From 2019 to 2020, the water budget of soybean grown in uplands were estimated and compared with the one grown in paddy fields. The calibration result of AP EX model for runoff showed that R² (Coefficient of determination) and NSE (Nash-Sutcliffe efficiency) were 0.90 and 0.89, respectively. In addition, the validated results of R² and NSE were 0.81 and 0.62, respectively. The comparative study of each component in water budget showed that the amounts of evapotranspiration and percolation estimated by APEX model were 549.1 mm and 375.8mm, respectively. The direct runoff amount from upland was 390.1 mm, which was less than that from paddy fields. The average amount of irrigation water was 28.7 mm, which was very small compared to the one from paddy fields.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.148.2-148.2
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• 2013

We prepared hydrophobic PDMS-coated porous silica as pre-concentration adsorbent for chemical warfare agents (CWAs). Since CWAs can be harmful to human even with a small amount, detecting low-concentration CWAs has been attracting attention in defense development. Porous silica is one of the promising candidates for CWAs pre-concentration adsorbent since it is thermally stable and its surface area is sufficiently high. A drawback of silica is that adsorption of CWAs can be significantly reduced due to competitive adsorption with water molecule in air since silica is quite hydrophilic. In order to solve this problem, hydrophobic polydimethylsiloxane (PDMS) thin film was deposited on silica. Adsorption and desorption of chemical warfare agent (CWA) simulants (Dimethylmethylphosphonate, DMMP and Dipropylene Glycol Methyl Ether, DPGEM) on bare and PDMS-coated silica were studied using temperature programed desorption (TPD) with and without co-exposing of water vapor. Without exposure of water vapor, desorbed amount of DMMP from PDMS-coated silica was twice larger than that from bare silica. When the samples were exposed to DMMP and water vapor at the same time, no DMMP was desorbed from bare silica due to competitive adsorption with water. On the other hand, desorbed DMMP was detected from PDMS-coated silica with reduced amount compared to that from the sample without water vapor exposure. Adsorption and desorption of DPGME with and without water vapor exposing was also investigated. In case of bare silica, all the adsorbed DPGME was decomposed during the heating process whereas molecular DPGME was observed on PDMS-coated silica. In summary, we showed that hydrophobic PDMS-coating can enhance the adsorption selectivity toward DMMP under humid condition and PDMS-coating also can have positive effect on molecular desorption of DPGME. Therefore we propose PDMS-coated silica could be an adequate adsorbent for CWAs pre-concentration under practical condition.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2004년도 Proceedings of the 4th Korea-China Joint Workshop on Nuclear Waste Management
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• pp.64-72
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• 2004

The dryer (ten per unit) are operating to remove tritium in PHWR(Pressurized Heavy Water Reactor). There are coming out heavy water adsorbent from operating the dryer (95 drums for ten year per unit) The amount of radioactivity of heavy water adsorbent almost exceed ninety times more than disposal limit-in-itself showed by The Ministry of Science and Technology. It has to be disposed whole radioactive waste products, however there are problems of increase at the expense of their permanent disposal. In this research, We have studied how to remove kinds of nuclear materials and amount of tritium with in heavy water adsorbent. As the result we could develop disposal equipment and apply it. D20 adsorbent have to contain below Gamma nuclide O.3Bq/g and tritium 100Bq/g "The Regulation for disposal of the radioactivity wastes" showed by The Ministry of Science and Technology. There fore. So as to remove amount of tritium and kinds of nuclear materials (DTO) we needed a equipment. Also we have studied how to remove effectively radioactivity with in Adsorbent. As cleaning heavy water adsorbent and drying on each condition (temperature for drying and hours for cleaning). Because there is something to return heavy water adsorbent by removing impurities within adsorbent when it is dried o high temperature. After operating, we have been applying this research to the way to dispose heavy water adsorbent. Through this we could reduce solid waste products and the expense of permanent disposal of radioactive waste products and also we could contribute nuclear power plant run safely. According to the result we could keep the best condition of radiation safety super vision and we could help people believe in safety with Radioactivity wastes control for harmony with Environment.

• 한국식품과학회지
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• 제28권4호
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• pp.644-649
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• 1996

산지와 품종을 달리한 94년산 일반미 6개 품종(오대벼(마현, 동송), 추청벼, 오까비, 동진벼, 히도메보레)과 통일미 1개 품종을 대상으로 최적의 밥맛을 내는 취반가수율을 관능검사를 통하여 조사하였다. 실험 목적이 품종간의 식미 차이를 평가하는 것이 아니고 품종별로 최적의 밥맛을 내는 가수율을 결정하는데 중점을 두었다. 그리고 각각의 쌀의 물리, 화학적 특성치들을 측정한 후 관능검사치와 비교하여 상관관계를 구함으로써 최적의 가수율에 영향을 미치는 인자들을 규명하고자 하였다. 취반시 최적 가수율은 아밀로즈 함량이나 쌀의 초기 수분함량과는 무관하였고 입폭과는 부의 상관관계 (r=-0.80)를 보였다. 단백질 함량과 최적 가수율과의 관계는 통일벼를 제외할 경우 상관관계를 갖지 않는 것으로 나타났으나 입폭, 취반팽창용적, 아밀로그램 최고점도가 최적 가수율에 유의적 영향인자로 나타났다.

• 한국환경보건학회지
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• 제44권1호
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• pp.24-30
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• 2018

Objectives: Based on the amount of amalgam, the duration of exposure, and the water pH, this study aims to investigate the change patterns in the mercury concentrations in water after amalgams have been introduced into sewage water. It is expected that the study results will be useful in improving the system for regulating the amount of mercury that is introduced into the environment. Methods: During the study, a glass test-tube with a cap was washed and disinfected using the glass laboratory device washing method. Then, 1, 2, 3, and 4 tabs were placed into a 10 mL pH 4 solution and 10 mL pH 7 distilled water. Each specimen was prepared in duplicate. The mean of the two mercury concentrations was used as the representative value, and the mercury concentration was measured using a mercury measurement device (DMA-80, Milestone, Italy) a total of eight times at one-week intervals. Results: The results show that the lower was the pH, the higher was the amount of amalgam. Also the longer was the duration, the more significant was the increase of mercury concentration in the water. Conclusions: Dental clinics are collected separately from dental clinics that used them. Given this, dental clinics in Korea must have the necessary facilities to separately collect mercury at their level. In addition, proper disposal systems and social attention to the proper management of dental wastes are required to prevent environmental pollution from mercury.

• 복식
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• 제55권5호
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• pp.101-107
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• 2005

In this article, mordant absorption rate by the Change of temperature and fabric, discharge level by water washing, mordant density and method in mordant dye are going to be handled. Besides, how treatment method will have an effect on absorption rate and color, is also going to be covered. An atom extinction photometer was used to measure the amount of mordant absorbed in fabric at each temperature and mordant type. It turned out that absorption rate differs according to the type of mordant and sample or temperature. Also it turned out that the mordant input amount has little influence on absorption rate, that is to say, if though you use more mordants, just tiny amount of mordant is going to be absorbed in cloth. It is true that the higher temperature goes up, the better mordant absorption gets. It is found that the type of mordant and sample, treatment period affects the discharge rate. Normally $15{\~}98\%$ mordant comes off the fabric by water washing, to be specific, $17{\~}47\%$ Iron by water washing and it has better performance on cotton and nylon than silk, $1\%{\~}52\%$ Aluminum by water washing and better absorption on silk, $36{\~}89\%$ Chrome by water washing and better absorption on silk, $50{\~}89\%$ copper by water washing and better absorption on silk, poor on cotton. The examination of the K/S values and colors between before and after soaping has been conducted under the circumstance that the test fabrics had been treated at $80^{\circ}C$ for 30 minutes with $0.2\%$ soaping solution. In case of pre-mordanted fabrics, the K/S value nosedived after soaping, meanwhile densely mordanted fabric's K/S value soared but after soaping, it dropped sharply. It turned out that soaping treatment deteriorates absorption much more than water washing. It's considered that $0.1 \%$ (W/V) of mordant density is appropriate.

• 한국환경과학회지
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• 제20권10호
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• pp.1297-1308
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• 2011

This study is to analyze the characteristics of golf course water usage using groundwater and rainwater data obtained from 17 golf courses in Jeju Island during 2007~2009. The groundwater usages were 246,275 $m^3/year$, 213,062 $m^3/year$, 155,235 $m^3/year$, and 126,666 $m^3/year$ in the west, south, east, and north regions, respectively. Monthly rate of the amount of groundwater usage to the amount of permission was 29.5%. The rainfall usages were 386,591 $m^3/year$, 326,464 $m^3/year$, 251,248 $m^3/year$, and 232,061 $m^3/year$ in the south, west, east, and north regions, respectively. Monthly rate of rainwater usage to the amount of water retention of golf courses was 19.6%. The average annual water usage in the 17 golf courses was 499,377 $m^3/year$. From the average usage, it was found that the rainwater usage (305,126 $m^3/year$ ) was 1.6 times higher than that of groundwater (194,251 $m^3/year$ ). That means the annual average rainwater usage to the entire water usage was 61.1%, which was above the criteria of 40%.