• 한국보건간호학회지
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• 제10권1호
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• pp.31-38
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• 1996

Disinfection is a very important process in water plant on account of our surface water usage. Particularly. the rainfall of Korea is concentrated in summer time. it is almost carried away to ocean before our utilization as water resource. To overcome the unbalance of water resource, artificial dams and reservoirs are constructed. According to such storage of water to aggravate water pollution and make the increase of water cleaning chemicals. Chlorine, as a main traditional chemical for water treatment. is focused on account of THMS formation in recent days. In this paper. the data of a water plant located in Seoul is adopted as the foundation of water quality analysis and introduce the substitute chemicals to supplement the harmful formation. additionally. Conclusions are summarized as follows: 1. The water quality of water resource is the worst in summer time and the supply of cleaning chemical is inevitably increased on account of general bacteria increase. 2. Chlorine, as a main chemical for water cleaning, formed the cancer-causing organic THMS with water molecules. 3. One of substitute chemical. chlorine dioxids suppress the formation of THMS comparing with the case of chlorine only. Therefore. the continuous research of substitute chemicals should be activated. 4. As the supply of disinfected clean water concerned with the citizen sanitary, the cultivation of professionals and academic conference must be needed on the basis of nation

• 한국식품과학회지
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• 제25권2호
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• pp.148-153
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• 1993

최근 sucrose polyesters(SPE)와 더불어 유지대체 물질로서의 사용이 검토되고 있는 glucitol fatty acid polyesters(GPE)를 합성한 후, 화학적 구조 및 상대적 에스테르 분포에 따른 치환도를 조사하였다. 본 연구에서 합성한 GPE는 순상 HPLC에 의해 단일 에스테르 그룹으로 분리되었으며, 분리된 에스테르 그룹의 치환도는 6으로서 GPE 전체가 glucitol fatty acid hexaester임을 알 수 있었다. GPE의 IR 스펙트럼에서 $1747\;cm^{-1}$에 나타나는 흡수대는 GPE 분자내에 glucitol과 지방산을 연결하고 있는 에스테르 결합이 존재함을 보여주었다. GPE는 H-NMR 스펙트럼에서는 glucitol의 hydroxyl proton의 시그널이 존재하지 않음을 볼 때 glucitol의 모든 수산기가 지방산과의 에스테르 결합에 참여하고 있음을 알 수 있었다. 또한 GPE의 H-NHR 스펙트럼을 정량적으로 해석한 결과는 수산기가(hydroxyl value) 측정에 의해 결정된 GPE의 치환도와 일치하였다. 이상의 결과를 종합하여 볼 때 본 연구에서 합성한 GPE는 glucitol fatty acid hexaester임이 확인되었고 향후 유지대체물질로서 사용되어질 가능성을 지닌 것으로 생각되었다.

• Environmental Analysis Health and Toxicology
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• 제30권sup호
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• pp.1.1-1.5
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• 2015

Objectives Despite the great contribution made by chemical substances to the development of modern civilization, their indiscriminate use has caused various kinds of damage to the global environment and human beings. Accordingly, the major developed countries and international society have tried to ensure the safe use of chemicals and a reduction in the use of hazardous chemicals through the establishment of the United Nations Environment Programme and various international agreements. In this reason, we tried to introduce about Green Chemistry progress at the present in worldwide and Korea. Methods We checked and analyzed relative journals, reports using keyword as like Green Chemistry, alternative chemicals, eco-friendly etc. and major country's government homepage search. Results Green Chemistry theory, which argues for the reduction or removal of harmfulness in chemicals throughout their entire life-cycle, has been spreading, and major developed countries, such as the US and Denmark, have developed and operate programs to provide reliable chemical information to help replace hazardous chemicals. Korea has also been conducting studies as like eco-innovation project. Through this project the "Alternative Chemical Search program," has been developed, distributed, and operated since 2011 to provide reliable information to small and medium-sized businesses that have difficulties collecting information to ensure conformity to international regulations. The program provides information that includes the regulations of major countries and Korea, information on 340 alternative chemicals, 70 application cases, and 1:1 consulting. Conclusions The Alternative Chemical Search program is expected to contribute to the establishment of response systems for regulation of Korean small and medium-sized businesses, and it also will be used to provide basic data for Korean hazardous chemical regulation, together with the Act on the Registration and Evaluation, etc. of Chemical Substances and the Chemical Control act, making it possible to establish an infrastructure for Green Chemistry in Korea and to increase national competitiveness.

• 한국식품과학회지
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• 제25권5호
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• pp.438-443
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• 1993

Physico-chemical properties of glucitol fatty acid polyesters (GPE)-one of the potential fat substitutes-were analyzed and compared with conventional edible oil. The refractive Index, apparent viscosity and melting point of S-GPE (soybean oil GPE) were 1.472, 103 cps. at $37^{circ}C\;and\;-53^{\circ}C$, respectively. S-GPE were liquid at room teperature and the Yellowness of S-GPE was slightly stronger than that of soybean oil. The acid value and smoke point of S-GPE were 0.06 and $200^{\circ}C$. To supplement the weak thermal stability of S-PEG, SP-GPE (soybean-palm blended oil GPE) was prepared with soybeanpalm blended oil (70% of soybean oil and 30% of palm oil). The appearance and color of SP-GPE was not much different from S-GPE but the smoke point of that was increased to $210^{\circ}C$. It means that thermal stability of GPE can be enhanced by increasing saturation of the fatty acid composing GPE. Because most of physico-chemical properties of S-GPE or SP-GPE were similar to conventional edible oil, they are expected to be considered as a potential fat substitute with further study for confirming the safety.

• 소성∙가공
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• 제13권3호
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• pp.262-267
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• 2004

Ultrasonic machining has been known as one of the conventional machining methods in the glass fabrication processes. In ultrasonic machining, typically, glass is removed by the impulse energy of the abrasive generated by the ultrasonic power. However, when the machining feature decrease under hundreds of micrometers, as conventional ultrasonic machining uses only the impulse energy of the abrasive, the speed of ultrasonic machining decreases significantly and the surface roughness becomes deteriorated. To overcome this size effect, the chemicals which can erode glasses, such as HF, XF, etc, are added to the slurry. The chemical-assisted ultrasonic machining method, so called, is another alternating effective way for micro machining of glasses. In previous work, we used the hydrofluoric acid (HF) as an additive chemical. But, as the HF solution is too poisonous to be used as a ultrasonic process additive, it is needed to be substituted by other safe chemicals. As results of the machinability comparison of several chemicals, the GST-500F was selected to replace the HF. The GST-500F (pH $4.0{\pm}1.0$) is non-volatile, odorless. During experimental works, it was shown that the machining rate increases 1.5 times faster than the conventional ultrasonic machining. The machining load also decreases. However, the enlargement of the hole diameter and significant tool wear are still the problems to be solved.

• 펄프종이기술
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• 제47권4호
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• pp.46-53
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• 2015

Paper strengthening system of PVAm (polyvinylamine) has been used with strong negative charge polymer for electrostatic neutralization due to strong positive charge of PVAm. Recently, because of the controversy caused by the possibility of remaining PAM monomers in white water, a search for paper strength agent that can substitute for PAM was suggested. Therefore, this study was carried out to evaluate a dry strength polymer of PVAm. Starch and CMC were used as a substitute for PAM. The dual polymer system of PVAm and anionic charge control agent such as anionic starch or CMC (carboxy methyl cellulose) were found to be very effective as strength agent compared to the chemicals based on acrylamide.

• 한국균학회지
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• 제6권1호
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• pp.9-14
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• 1978

Mycogone병(病) 방제시(防除時)에 사용(使用)하든 Benomyl의 효과가 감소(減少)되여 이에 대체(代替) 사용(使用)할 수 있는 약제(藥劑)를 찾기 위(爲)해 본시험(本試驗)을 수행(遂行)한 결과(結果) 다음과 같은 몇가지 결론(結論)을 얻었다. 1. Benomyl에 내성(耐性)인 mycogone병원균주(病原菌株)에 대한 방제약제(防除藥劑)로는 Vitathiram, RH2161, Difolatan 등(等)이 효과가 있었으나 양송이 균사생장(菌絲生長)에 있어서 약해(藥害)를 유발한다. 2. Benomyl에 내성(耐性)인 병원균주(病原菌株)를 방제(防除)하는 약제(藥劑)로서는 Vapam과 Basamid등(等)이 유효하였으며 이들은 Formalin에 비(比)하여 40배(倍)의 높은 살균효과가 있었다. 3. Basamid와 Vapam은 복토(覆土)에 100ppm농도(濃度)로 처리(處理)하여 15일후(日後) 사용(使用)하여도 약해(藥害)가 없었다. 4. Basamid난 Vapam은 Benomyl에 내성(耐性)인 균주(菌株)에서도 방제효과가 높았고 건전(健全)한 버섯의 수량(收量)도 많았다.

• 한국식품과학회지
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• 제24권3호
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• pp.247-250
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• 1992

최근 유지 대체물질로 사용이 검토되고 있는 sucrose polyesters(SPE) 합성에 사용하는 지방산 Na염 중의 유리알카리 및 수분, 그리고 sucrose, potassium carbonate에 함유된 수분함량이 SPE 합성에 미치는 영향을 조사하였다. 지방산 Na염에 존재하는 미량의 유리알카리는 SPE 합성을 저해하는 것으로 나타났으며 그 함량을 0%에서 5%까지 변경시킴에 따라 SPE 제조수율은 92%에서 점차 감소하여 45.5%로 되었다. 따라서 지방산 Na염을 제조하기 위한 비누화 반응시, 대두유 지방산메틸에스테르(fatty acid methyl esters, FAME)의 당량보다 적은 당량비(0.9 : 1)의 NaOH를 사용, 대두유 FAME과 반응시켜 유리알칼리가 함유되지 않은 대두유 지방산 Na염을 제조하였다. 지방산 Na염이나 sucrose, potassium carbonate에 흡수되는 수분 역시 SPE 합성을 저해하였는데, $105^{\circ}C$에서 6시간 건조하여 잔존수분을 제거한 후 합성한 SPE의 제조수율(92%)은 건조하지 않은 원부재료로 합성한 SPE의 수율(89%)보다 높았다. 유리알카리 및 수분이 제거된 대두유 지방산 Na염, sucrose 및 potassium carbonate를 대두유 FAME과 반응시켜 제조한 대두유 SPE의 제조수율은 91.7%로서, SPE 합성에 있어서 사용하는 지방산 Na염에 잔존하는 유리알카리 및 원부재료의 보관중에 흡수될 수 있는 미량의 수분을 반응이전에 제거함으로써 이들에 의한 SPE 합성저해작용을 방지할 수 있었으며 재현성 있는 SPE 합성을 할 수 있었다.

• 통합자연과학논문집
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• 제14권4호
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• pp.155-158
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• 2021

To study the effects of hormones and neurotransmitters, zebrafish (Danio rerio) are a great substitute for water fleas (Daphnia). The zebrafish is an ideal vertebrate model because it has a transparent embryonic stage. It is easy to get consistent heart rate measurements in embryonic zebrafish when treating them with hormones and neurotransmitters. To observe the heart rate, two to three embryonic zebrafish are anesthetized with MS-222 and then transferred to a glass slide specifically designed for heart observation and easy application of various chemicals. After the heartbeats are counted for 2 minutes, apply either 100 µM epinephrine or 100 µM acetylcholine to the zebrafish. Wait 5, 10, and 20 minutes and count the heartbeats at each time point. All procedures are repeated three times. The final results are averaged and analyzed by using statistical methods. The above method which we have developed is practical enough for high school students to measure the heart rate in zebrafish under various conditions and to analyze the data set.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.87.1-87
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• 2003

Powdery mildew on strawberry plants, caused by Spherotheca aphanis (Wallr.) U. Braun var. aphanis, is the most serious disease for strawberry production. There is a demand to develop the substitutes for chemicals which are more environment friendly materials. Control of powdery mildew was evaluated on Akihime, Sachinoka, Dochiodome, Noyho and Redpearl varieties grown in the greenhouse. Applications of 1％, 0.5％, and 0.25％ of sodium bicarbonate (NaHCO3Nyoho in greenhouse experiments. Non-phytotoxicity was revealed on the leaves and fruits of strawberry at these concentrations. This$.$result indicates that a mixture of sodium bicarbonate and tween 20 is a useful substitute for fungicides to control powdery mildew of strawberry.