• 제목/요약/키워드: Absorption test

검색결과 1,424건 처리시간 0.028초

보존처리용 세척제에 대한 토기의 이온용출 특성연구 (A Study on Ion Extraction Characteristics of Ceramics by Cleaning Agents)

  • 박대우;강현미;남병직;장성윤;함철희
    • 보존과학연구
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    • 통권31호
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    • pp.43-57
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    • 2010
  • This study intends to provide quantitative data about the extraction characteristics of major elements of earthenware by executing soaking test of cleaning agents. It aims at providing basic data for the stability assessment when applying the cleaning agents for conserving earthenware. The data will be extracted from the analysis of co-relationship between the physical characteristics and the ion extraction characteristics. XRD analysis displayed that AT-1, AT-2 and AT-3 which did not generate mullite were fired at lower than 1,000 whereas AT-3 and AT-5 that included mullite were higher than 1,000. The degree of absorption was AT-4 > AT-2 > AT-1 > AT-3 > AT-5 in order and the correlation between the degree of absorption and firing temperature of earthenware displayed a positive correlation. Extraction amount of oxalic acid which was used for the removing iron oxide was AT-1 > AT-2 AT-4 > AT-3 > AT-5 in order. and the ion extraction data displayed that there is a positive correlation with absorption level. However AT-1 and AT-2 which were fired at lower temperature showed that there was no correlation between the ion extraction characteristics and absorption level. Ion extraction of citric acid produced little amount compared with the one of oxalic acid, yet it caused less damage to earthenware than oxalic acid when it applied. The result of ion extraction level in the absorption test displayed that Fe had higher level than in Si, Al from the test for both oxalic acid and citric acid. Based on the regression analysis of the data from the previous studies, the physical characteristics of the earthenware and ion extraction level, further studies will be conducted on the predicting technique on the extraction characteristics of major elements of earthenware samples for the conservation in future.

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Comparative Estimation of Exposure Level and Health Risk Assessment of Highly Produced Pesticides to Agriculture Operators by Using Default Dermal Absorption Rate or Actual Measurement Values

  • Kim, Su-Hyeon;Lee, Chang-Hun;Kim, Ki-Hun;Jeong, Sang-Hee
    • 대한의생명과학회지
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    • 제22권4호
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    • pp.199-206
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    • 2016
  • Pesticides are widely used to prevent loss of agricultural production but extensive exposure can induce health problems to pesticide operators. This study was performed to evaluate the health risk of highly produced pesticides used in fruit growing farm land by comparison of estimated exposure level with AOEL using KO-POEM program. AOEL was driven based on NOAEL of each pesticide evaluated by JMPR, EFSA or KRDA. In calculation of exposure level, types of formulation, dilution factors, spraying duration and motor type and exposure protection device were allocated according to actual condition of use. Dermal absorption rate was differently applied among EFSA default values (25% or 75%), general default value (10%) or real test result values to know the plausibility of default values and safety of pesticide to operators in outline. Twenty pesticide ingredients (fungicides and insecticides) were produced more than 30 tons per year, which were mancozeb, chlorothalonil, imidaclopirid and etc in order. Dermal absorption rates obtained from studies were various from 0.07 to 81% but mostly under 10%. The estimated exposure levels showed big differences more than 10 times higher when using EFSA default rate and up to 5 times higher when using general rate of 10% comparing using rates of test results. Mancozeb, chlorthalonil, diazinon and chlorpyrifos presented still higher exposure level than AOEL even when using test absorption rate from study, which suggests that re-evaluation of AOEL or dermal exposure absorption rate or strict management are required for health protection of operators who use those four pesticides in farm land.

Boltzmann법에 의한 목재 흡수시 확산계수 추정 (Estimation of Moisture Diffusivity during Absorption by Boltzmann Transformation Method)

  • 강욱;정우양
    • Journal of the Korean Wood Science and Technology
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    • 제37권1호
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    • pp.1-11
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    • 2009
  • 외장용 기둥재는 년중 사용환경에서 액상수와 직접 접촉할 수가 있으나, 이에 대한 연구는 그다지 많지 않다. 목재의 섬유방향에서 결합수와 자유수 확산계수를 포함한 수분확산계수를 측정하기 위해 상온에서 흡수실험을 실시하였다. 흡수성은 느릅나무, 까치박달나무, 헴록, 가문비나무, 라디에타 소나무, 고로쇠나무 순으로 크게 나타났다. Boltzmann 변환법으로 구한 확산계수는 저함수율에서 섬유포화점 부근까지 감소하다가 최대함수율 부근에서 급격히 증가하는 경향을 나타내었다. 함수율 변화에 따른 확산계수는 $10^{-10}{\sim}10^{-7}m^2/s$ 정도의 값을 나타내었다.

금속 및 샌드위치 복합재 유도탄 구조체의 흡음 및 차음 특성에 관한 실험적 연구 (Experimental Study on Acoustic Absorption and Transmission Characteristics of Aluminium and Sandwich Composite Structure)

  • 이윤규;이대은;진병대;이동민
    • 한국군사과학기술학회지
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    • 제21권3호
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    • pp.288-294
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    • 2018
  • Recently, as the speed and performance of the launcher and the missile have been improved, it is necessary to consider the acoustic load of launching and flight in initial design step. In this paper, an experimental study on acoustic absorption and transmission characteristics of aluminium vs. sandwich composite structures were conducted. The overall noise reduction was evaluated by performing an acoustic test in the reverberation room, and the acoustic absorption and transmission loss of the structures were analyzed by conducting the sound absorption test inside the structure.

복합가속열화시험에 의한 폴리머 피뢰기의 경년특성 (Aging Characteristics of Polymer Lighting Arrester by Multi-Stress Accelerated Aging Test)

  • 송현석;이재봉;장상옥;한용희;오재형
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2004년도 춘계학술대회 논문집
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    • pp.86-89
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    • 2004
  • Recently polymer arresters are being used widely but we don't have appropriate long term characteristics test methods. Therefore we need to develop special test facility to evaluate long term reliability of polymer arresters. It's polymeric housing can be degraded by environmental stress and the interface between housing and inner module can be affected by moisture absorption. This moisture absorption can cause leakage current and tracking in the interface. We developed multi stress accelerated ageing test facility to simulate field conditions including UV, temperature, humidity, voltage, salt fog and rain. In addition, we carried out field exposure test at the outdoor test yard and characteristics analysis of field operated specimens to evaluate accelerating factor of this accelerated aging test.

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충주 지역 화강암의 풍화지수 및 일축압축강도 추정에 관한 연구 (The Weathering Index and Prediction of Uniaxial Compressive Strength for Chung-Ju Granite)

  • 엄태욱;김학문;김찬국;장경준;표명렬
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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    • pp.863-874
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    • 2008
  • We have to judge engineering properties of rock accurately in order to design and construct rock structure safely and economically. Among the rock tests, the test result of UCS(Uniaxial Compressive Strength) is very important factor used in the variety ways for designing and construction of underground structures, rock slope and foundation analysis. But the UCS test has some disadvantages of intact sample preparation such as because the shape of sample has to be regular cylindrical, cube or rectangular. In order to solve those problem, indirect tests are used such as point load test, schmidt hammer test, absorption test, dry density to predict UCS of rock. Those tests are easy to prepare sample and convenient to carry out the tests, so it is simple and costs less. Schmidt hammer test are frequently used in the construction site, because it is handy and easy to use, but there is concern of misuse without classifying the specification of each schmidt hammer. Thus, this study suggested presumptive numerical formula related on each specification of schmidt hammer test, point load test, absorption test and dry density also. We compared presumptive numerical formula and R-square through schmidt rebound assessment method already brought up. Also, through the test we offer the extent of weathering index according to the weathering grade.

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목분의 첨가량에 따른 산화마그네슘 경화체의 밀도 및 흡수율 특성 (Density and Water Absorption Ratio Property of the Magnesium Oxide Matrix According to Wood flour Addition Ratio)

  • 정병열;김헌태;이상수;송하영
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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    • pp.236-237
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    • 2014
  • Recently, it changes to the frame construction in the wall type structure for the life span improvement of the apartment house of our country. The execution of the light panel increased while the execution of the frame construction increased. Therefore, the density and absorption ratio of the magnesium oxide matrix according to the wood flour amount of addition ratio property try to be analyze for the lightweight of the surface material of the light panel. The test result, the density has been declined as the addition ratio increase of the wood flour. In the case of the water absorption ratio, water absorption ratio has been increased as addition ratio increase of wood flour. However, wood flour addition ratio 15% determined the most appropriate when considering the density and water absorption ratio.

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축 하중을 받는 AI/CFRP 혼성튜브의 에너지흡수 특성 (Energy Absorption Characteristics of Al/CFRP Compound Tubes Under Axial Compression)

  • 이길성;차천석;문지현;양인영
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2004년도 추계학술대회 논문집
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    • pp.108-113
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    • 2004
  • The compressive axial collapse tests were performed to investigate energy absorption characteristics of Al/CFRP compound tubes which are aluminum tubes wrapped with CFRP (Carbon Fiber Reinforced Plastics) outside the aluminum circular and square tubes. Based on collapse characteristics of aluminum tubes and CFRP tubes respectively, the axial collapse tests were performed for Al/CFRP compound tubes which have different fiber orientation angles. Test results showed that Al/CFRP compound tubes supplemented the unstable brittle failure of CFRP tubes due to ductile nature of inner aluminum tubes. In the light-weight aspect, specific energy absorption were the highest for Al/CFRP, CFRP in the middle, and aluminum the lowest. Also, specific energy absorption of circular tubes was higher than square tubes'. It turned out that fiber orientation angle of Al/CFRP compound tubes influence specific energy absorption together with the collapse modes of the tubes.

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교육시설에 적용 가능한 태양열 흡수식 냉각 시스템 (Solar Absorption Cooling System applicable to Educational Facilities)

  • 윤성민;백인수;한영태;남효갑
    • 교육시설 논문지
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    • 제18권3호
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    • pp.35-41
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    • 2011
  • Performance of a small-capacity solar absorption cooling system was investigated experimentally. Ten sets of evacuative-tube solar-heat collectors and a 5 kW single-stage absorption cooler were combined to produce a hybrid cooling system. The performance of the cooling system was measured using a tim-coil unit installed in a small plastic storage. It was found from the test on a sunny day of May that when the temperature of the hot water supplied from the solar collectors to the generator of the absorption cooler reached $60^{\circ}C$, the absorption cooler started cooling and the cold water temperature measured from the fan-coil unit reached $18^{\circ}C$. The COP, which is defined as the ratio of the cooling power to the total electrical power input was higher than 1.0.

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직물 복합재료 계란판의 압축 특성과 에너지 흡수율 (Compression Characteristics and Energy Absorption of Composite Egg-Box Panels)

  • 정지규;장승환
    • 대한기계학회논문집A
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    • 제30권12호
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    • pp.1603-1610
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    • 2006
  • In this paper compressive characteristics of composite egg-box panels were investigated and energy absorption was calculated from the nominal stress-strain relations obtained by the compressive tests. Several different stacking sequences and number of plies were introduced for investigation of static compression characteristics and the energy absorption rates of composite egg-box panels. The compressive stress-strain relation and energy absorption of various composite egg-box panels were compared with those of aluminium egg-box panels. From the test results it was found that the fracture behavior of composite egg-box panel was affected by stacking angle causing different local deformation, during lay-up and draping processes and types of prepreg; that is, plain weave carbon/epoxy and 4-harness satin glass/epoxy. The energy absorption capacity of composite egg-box panels were proved to be higher than that of aluminium egg-box panels with low mass.