• Title/Summary/Keyword: Chemicals

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The Formation of Information Network on Chemical Safety with Toxicological Data in China

  • Yao, Peipei
    • Toxicological Research
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    • 제17권
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    • pp.237-239
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    • 2001
  • China is an Asia country with population more than 1,200 millions. According to the national registration, the number Q[ chemicals commonly used in China reaches 80,000, and the number of chemicals produced in China is more than 30,000, about 10% of which has been evaluated for safety and has the toxicological data. Most of the chemicals still need safety evaluation and a part of chemicals need a renewed evaluation. At present. the information techniques and telecommunication network are develop-ing widely and intensively. It is used not only in different institutions and enterprises, but also in many governmental sectors in my country. Here is the introduction of the situation of information network on chemical safety with toxicological data and the work done by different institutions and governmental sectors in China.

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Estrogenic Activity Assessment of Alkylphenolic chemicals using in vitro assays : III. Rcombinant Yeast Transcriptional Assay

  • Park, Hyo-Joung;Lee, Ho-Ja;Park, Kyunghee;Ryu, Jae-Chun
    • 한국환경독성학회:학술대회논문집
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    • 한국환경독성학회 2001년도 춘계심포지움 및 학술발표회
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    • pp.127-127
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    • 2001
  • There is a concern that chemicals in our environment are affecting human health by disrupting a normal endocrine function. Much of the concern has focused on chemicals that can interact directly with steroid hormone receptors. The ability of certain man-made chemicals to mimic the effects of natural steroid hormones and their potential to disrupt the delicate balance of the endocrine system in animals are of increasing concern. (omitted)

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수침출토목재에 PEG4000과 Sucrose처리에 따른 변화 (Micromorphological Changes of Waterlogged Archaeological Wood in PEG4000 and Sucrose Treatment)

  • 강애경;박상진
    • 보존과학회지
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    • 제5권2호
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    • pp.3-14
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    • 1996
  • The chemicals are PEG $\#4000$ and sucrose, which have been conventionally used for the treatment of waterlogged wood. The present investigation was undertaken in order to reveal difference of the impregnation between the chemicals, but also to contribute to the explanation of the chemicals penetration process and distribution within wood structure. Comparable observation concerning the deposits shapes of chemicals after treatment, PEG4000 penetrated samples were occurred at the cell wall shrinkage and cracks, whereas the majority of the cells and lumens were entirely filled with a crystalline structure. Sucrose penetrated samples remained almost like sound wood, although the penetration ristricted only the cell walls was filled by amorphous structure.

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상수처리 수질제어를 위한 약품주입 자동연산 (Optimum chemicals dosing control for water treatment)

  • 하대원;고택범;황희수;우광방
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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    • pp.772-777
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    • 1993
  • This paper presents a neuro-fuzzy modelling method that determines chemicals dosing model based on historical operation data for effective water quality control in water treatment system and calculates automatically the amount of optimum chemicals dosing against the changes of raw water qualities and flow rate. The structure identification in the modelling by means of neuro-fuzzy reasing is performed by Genetic Algorithm(GA) and Complex Method in which the numbers of hidden layer and its hidden nodes, learning rate and connection pattern between input layer and output layer are identified. The learning network is implemented utilizing Back Propagation(BP) algorithm. The effectiveness of the proposed modelling scheme and the feasibility of the acquired neuro-fuzzy network is evaluated through computer simulation for chemicals dosing control in water treatment system.

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제설제 종류에 따른 제설성능 평가 (Deicing Performance with Deicer Types)

  • 이병덕;이찬영;윤병성;이주광;정영환
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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    • pp.371-374
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    • 2005
  • In this study, calcium chloride($CaCl_2$), sodium chloride (NaCl), organic acids-containing deicer(NS 40, NS 100), mixed deicier($NaCl\;70\%\;+\;CaCl_{2}\;30\%,\;NS\;40\;70\%\;+\;CaCl_{2}\;30\%,\;NaCl\;70\%\;+\;NS\;40\;30\%,\;NS\;40\;70\%\;+\;NaCl\;30\%$) is investigated based on the laboratory test for deicing performance. Test items for deicing performance were ice melting and ice penetration, freezing point depressions and eutectic points, pH, thermal properties for selected deicing chemicals. As a test results, in case of the use chloride-containing deicier in area that concrete structures has subjected to freez-thaw reaction in winter season, it showed desirable method that use deicing chemicals mixed with optimum ratio rather than use one deicing chemicals when is consider to deicing performance and effects, corrosion of steel materials, freez-thaw resistance of concrete. When use various deicing chemicals mixed, NS40($70\%$)+Calcium chloride($30\%$) showed the best effective method.

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Reactive Mesogen Mixtures for Integrated Optical Films

  • Lee, Hee-Kyu;Lee, Seung-Eun;Cumming, S.A.;Verrall, M.;Parri, O.;Harding, R.;Marden, S.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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    • pp.266-269
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    • 2003
  • TFT LCD mode has some well-documented performance limitations, namely limited viewing angle, inversion of the gray scale levels and poor luminance efficiency because of the necessity of using crossed polarisers attached to the display cell. During the last few years many initiatives have been undertaken to solve these problems by incorporation birefringent films of various designs into the LCD module. Controlling the optical performance of LCDs often requires combination of liquid crystal material properties, cell parameters and optical films. Such optical films have traditionally been made with stretched polymer materials such as polycarbonate, but recently coated liquid crystalline materials have been used to give improved optical films which can greatly enhance the performance of LCDs. We have now developed reactive mesogen materials to add ultra-thin optical layers into the display structure, and these allow the potential for many new applications.

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Toxicological Mechanism of Endocrine Disrupting Chemicals: Is Estrogen Receptor Involved?

  • Jeung, Eui-Bae;Choi, Kyung-Chul
    • Toxicological Research
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    • 제26권4호
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    • pp.237-243
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    • 2010
  • Endocrine disrupting chemicals (EDCs) have been shown to interfere with physiological systems, i.e., adversely affecting hormone balance (endocrine system), or disrupting normal function, in the female and male reproductive organs. Although endocrine disruption is a global concern for human health, its impact and significance and the screening strategy for detecting these synthetic or man-made chemicals are not clearly understood in female and male reproductive functions. Thus, in this review, we summarize the interference of environmental EDCs on reproductive development and function, and toxicological mechanism(s) of EDCs in in vitro and in vivo models of male and female reproductive system. In addition, this review highlights the effect of exposure to multiple EDCs on reproductive functions, and brings attention to their toxicological mechanism(s) through estrogen receptors.

뽕나무 줄기마름병(동고병) 약제방제에 대하여 (The comparable test of the chemicals on control effects of mulberry die-back disease.)

  • 김영택;정봉조
    • 한국잠사곤충학회지
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    • 제10권
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    • pp.53-55
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    • 1969
  • 1. 본시험은 1967년 가을부터 1968년 가을까지 살균제 루베롱(EMP), PMF, 석회유황합제, 쿠론(PCP제), PMA 5종을 공시하여 뽕나무 줄기마름병에 대한 그 효과를 비교 검토하였다. 2. 뽕나무 줄기 마름병에 대한 약효에 있어서는 루베롱, PMF는 그 효과가 우수 하였으며, 다른 약제 및 무처리와는 고도의 유의성이 있었고 다른약제는 무처리에 비하여 별로 그 효과를 인정할 수 없었다. 3. 본병 방제를 위하여 루베롱(EMP) 1500배액을 9월과 10월에 걸쳐 2회정도 10a당 150$\ell$를 가지기부에 충분히 살포하면 가장 효과적이고 다음은 PMF가 효과가 좋았다.

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수종의 약품이 개구리의 생존율과 변태속도에 미치는 영향에 관한 연구 (A Study on the Effect of Chemicals on the Survival Rate and the Metamorphosis Speed in Rana nigromaculata Hallowell.)

  • 한양일;조소남
    • 한국환경보건학회지
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    • 제5권1호
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    • pp.66-70
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    • 1978
  • This experiment is to search what some chemicals polluting water have an effect on the Rana nigromaculata Hallowell, in the survival rate and the metamorphosis speed from a tadpole to a young frog. 1. The fatal thickness by some agricultural chemicals and copper sulfate is different from one another. The fatal rate in the contrast group is 15 percent, and particulary Dithane M-45 is the most among the all reagents. 2. The effect on the anamorphosis is very severe. In the case of contrast group, it appears to stage 25, but it is not to appear at the group used agricultural chemicals. 3. The less the thickness of that is, the less the influence of the survival rate and the metamorphosis speed. 4. The density of the agricultural chemical is in inverse proportion to the survival rate and the metamorphosis speed, and the other side, the fatal rate is proportion.

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