• Journal of Ginseng Research
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• 제6권1호
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• pp.30-37
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• 1982

This study was conducted to investigate the water vapor permeability of packaging film, Al- foil laminated paper, and sorption properties of dehydrated and powdered foods. The results are as fellows. 1. Absorption rate of each products was greately affeoted by physicochemical properties of foods rather than initial moisture contents of the products. 2. The absorption rate of each products were in the order of freeze dried coffee, spray dried coffee, freeze drie4 ginseng extract, spray dried ginseng extract, ginger tea, black tea, citrus juice Powder and ssang wha tea. 3. Most of the products such as freeze dried coffee, spray dried coffee, freeze dried ginseng extract, ginger tea and black tea have shorter than a month of shelf life. 4. The stability of the products were greatly affected by its desorption properties than the degree of desorption of moisture. 5. Water vapor permeability of packaging materials which are laminated Al-foil with polythylene and glassin paper were mainly affected of thickness of Al-foil and polyethylene.

• Water Engineering Research
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• 제1권3호
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• pp.171-185
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• 2000

A mathematical model to adequately predict complex mixing characteristics of sorptive polluants in natural streams with pools-and-riffes has been developed. In this model, sorption of pollutants onto the bed sediment as well as mass storage and exchange in the storage zones were incorporated into one-dimensional mass balance equatins. The geometric and hydraulic characteristics of the pool-riffle sequences were properly conceptualized. Simulations with parameters of pool-and-riffle streams better fit the measured data in overall shape and peak concentration than simulations with parameters for uniform channels. The analyses on the characteristics of the storage zone model parameters reveal that a linear relationship between the logrithm of the storage zone volume ratio and a function of the friction factor exists. A linear relatiohship might also be tenatively assumed between the logarithm of the dimensionless mass exchange coefficient and the logarithm of the aspect ratio of the storage zone if some of the high values of the dimensionless mass exchange coefficient collected on the successive bed forms are excluded.

• Restorative Dentistry and Endodontics
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• 제36권4호
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• pp.280-289
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• 2011

연구목적: 본 연구의 목적은 다양한 소수성을 지닌 최신 상아질 접착시스템과 저수축 silorane 레진의 미세인장결합강도를 평가하는 것이다. 연구 재료 및 방법: 36개의 갓 발치된 제3대구치를 이용했다. Low-speed diamond saw를 사용하여 교합면에 평행하게 치관을 잘라 middle dentin을 노출시켰다. 치아를 무작위로 9 group으로 나눴다. Silorane self-etch adhesives (SS), SS + phosphoric acid etching (SS + pa), Adper Easy bond (AE), AE + Silorane system bonding (AE + SSb), Clearfil SE bond (CSE), CSE + SSb, All-Bond 2 (AB2), AB2 + SSb, All-Bond 3 (AB3). 접착제를 적용한 후에 Filtek LS (3M ESPE)를 2 mm씩 3회 적층충전하였다. 각 층은 40s씩 광중합하였다. 0.8 mm ${\times}$ 0.8 mm stick을 Micro Tensile Tester로 1 mm/min cross-head speed의 인장력을 가하였다. 파절양상를 관찰하기 위해 광학현미경을 이용하였다. 5가지 접착제의 소수성정도를 결정하기위해 water sorption test하였다. 결과: silorane 레진과 5가지 접착제의 ${\mu}TBS$: SS, 23.2 ${\pm}$ 6.9 MPa; CSE, 19.4 ${\pm}$ 4.4 MPa; AB3, 30.3 ${\pm}$ 4.0 MPa; AB2와 AE, no bond. Additional layering of SSb: CSE + SSb, 26.2 ${\pm}$ 10.3 MPa; AB2 + SSb, 33.9 ${\pm}$ 7.3 MPa; AE + SSb, no bond. 높은 ${\mu}TBS$는 cohesive failure와 관련있었다. SS는 낮은 가장 낮은 water sorption을 보였고 다음으로 AB3, AE, CSE, AB2 순서였다. AE는 가장 높은 용해도를 나타냈고 다음으로 CSE, AB2였다. 결론: 접착제의 소수성이 증가할수록, silorane 레진의 접착강도도 증가하였다. 비전용접착제 위에 silorane adhesive bonding을 layering하는 것은 AB2 + SSb 그룹에서만 결합강도를 유의하게 증가시켰다. AB3는 SS와 유사한 ${\mu}TBS$ & water sorption을 나타냈다. 따라서 AB3는 siloran resin을 접착시키는데 SS를 대체할만한 경쟁력있는 접착제이다.

• 멤브레인
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• 제1권1호
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• pp.34-43
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• 1991

물에 대해 수착선택성이 높은 아세트산 셀룰로오스 치밀막(CA막)과 에탄올에 대해 수착선택성이 높은 실리콘 고무막(SR막)을 통한 물(1)/에탄올(2) 이성분 혼합액의 투과증발에 있어서 막의 친화성과 최적 조업조건의 관계를 조사하였다. CA막과 SR막을 제조하여, 이들 막에서의 수착량, 수착선택도, 투과증발 분리도 및 투과증발 속도를 실험으로 구하고 서로 비교하였다. 하류압력의 영향을 Thompson다이아그램을 써서 분석하였고, 공급액 농도와 조업 온도 변화에 따른 수착 및 투과증발 특성을 활동도 계수, 가소화 효과, 활성화에너지 등으로 설명할 수 있었다. CA막을 사용한 물의 분리의 경우에는 물에 대한 투과증발 분리도 ($[\alpha^2_1]_{PV}$) 및 투과증발 속도 모두 하류압력이 낮고, 공급액의 농도가 중간 정도이고, 온도가 높은 조업조건이 유리하였다. 그러나 SR막을 사용한 에탄올의 분리의 경우에는 에탄올에 대한 투과증발 분리도 ($[\alpha^2_1]_{PV}$) 는 하류압력이 높을수록, 공급액 중의 에탄올 농도가 낮을수록, 조업온도가 낮을수록 증가하였지만, 투과증발 속도는 반대의 경향을 나타내었다.

• 한국식품과학회지
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• 제18권3호
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• pp.234-240
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• 1986

탈지대두를 파파인 및 ${\alpha}$-아밀라아제를 사용하여 분해시켜 얻은 탈지대두분해물의 흡습특성을 조사하였고 이를 이용하여 모형 중간수분식품을 제조하였다. 탈지 대두분해물의 등온흡혼곡선(等溫吸混曲線)은 단백질 및 전분질이 많이 분해될 수록 동일한 수분함량에서 수분활성도가 저하되었으며 BET 일분자층값(BET monolayer value)은 증가 하였다. 단백질분해정도가 약 78%인 탈지대두분해물의 보수력은 슈크로오스보다 높았으며 소르비틀에 조금 뒤 떨어졌다. 탈지대두분해물의 등온흡습곡선에 가장 적합한 식은 Oswin식이었고 단백질 분해가 많이 진행된 경우에는 Halsey식이 가장 적합하였다. 쌀가루와 탈지대두분해물로 제조한 모형(模型) 중간수분식품(中間水分食品)은 Grover식과 Lang 및 Steinberg식으로 수분활성도를 예측할 수 있었다. 탈지대두분해물을 첨가하여 제조한 식빵에서는 저장성이 향상(向上)됨을 관찰하였다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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• pp.23-26
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• 2004

Methyl Tertiary-Butyl Ether is one of several fuel oxygenates added to gasoline to improve fuel combustion and reduce tile resulting concentration of hydrocarbon. Thus, MTBE transfer readily to groundwater from gasoline leaking from Underground Storage Tank. Therefor, there are significant risks and costs associated with the water contamination. MTBE is far more water soluble than gasoline hydrocarbon. The purpose of the this study is to test the ability of ground tire with facultative bacteria. Bacillus brevis, to sorb MTBE. The process is consisted both batch and column experiment to determine the sorption capacity. And Biofilm is observed by SEM in the column. Finally, it is clear that ground tire represent an attractive and relatively inexpensive sorption medium for a MTBE. The authors can surmise that to determine the economic cost of ground tire utilization, tile cost to sorb a given mass of contaminant by ground tire will have to be compared to currently accepted sorption media. and Bacillus brevis strain was eliminated on MTBE, too. The biobarrier that ground tire with bacteria, has potential for use in the remediation of MTBE-contaminated environments.

• Food Science and Biotechnology
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• 제14권1호
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• pp.68-72
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• 2005

Moisture sorption characteristics of edible composite films were determined and compared against moisture barrier properties. Edible composite films were Z1 (zein film with polyethylene glycol(PEG) and glycerol), Z2 (zein film with oleic acid), ZA1 (zein-coated high amylose corn starch film with PEG and glycerol), and ZA2 (zein-coated high amylose corn starch film with oleic acid). Z2 film showed the lowest equilibrium moisture content (EMC), monolayer value ($W_m$), water vapor permeability (WVP), and water solubility (WS). Surface structure of Z2 was relatively denser and finer than that of other edible films. GAB $W_m$ and C values decreased, while K values increased with increasing temperature. Correlation coefficients of WS:EMC and WVP:EMC at Aw 0.75 were higher than those of WS: $W_m$ and WVP: $W_m$, respectively. EMC values at Aw 0.75 appeared useful for evaluating or predicting moisture barrier properties of edible films.

• 아시안잔디학회지
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• 제20권1호
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• pp.47-55
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• 2006

본 실험은 농약 흡착제(adsorbent)로서 입상 활성탄(활성탄 I 및 활성탄 II) 및 차콜의 사용가능성을 알아보기 위하여 흡착질(adsorbate)로 현재 골프장에서 사용하고 있는 살충제인 스미치온(Fenitrothion)과 살균제인 호리쿠어(Tebuconazole)를 대상으로 하였다. 흡착실험에서는 스미치온 및 호리쿠어의 처리 농도별 흡착에 미치는 영향과 흡착제의 입자크기가 흡착에 미치는 영향을 살펴본 결과, 흡착실험에서는 흡착제의 입자 크기가 작을수록 높은 흡착율을 보였으며, 활성탄이 차콜에 비하여 상대적으로 높은 흡착율을 나타내었다. 그러나 스미치온의 탈착(desorption)에 관한 실험에서는 활성탄 및 차콜 모두 1200mm 이상의 강우량에서도 스미치온이 용탈되지 않았으므로, 차콜 또한 활성탄과 함께 골프장 농약 흡착제로서의 이용 가능한 것으로 나타났다.

• Journal of Pharmaceutical Investigation
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• 제22권1호
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• pp.41-48
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• 1992

Six common tablet disintegrants (corn starch, Avicel PH102, calcium carboxymethylcellulose, Primojel, Kollidon CL and Ac-Di-Sol) were used at the concentration of 0, 2, 4 and 6% (w/w) in salicylamide tablets made with wet granulation method. Certain physical parameters of the disintegrants (moisture sorption, hydration capacity and bulk density) were determined to evaluate their relative efficiency. The disintegration time and dissolution rate of the tablets were correlated well with the ranks of initial rate of moisture sorption for each disintegrant as follows; Ac-Di-Sol, Kollidon CL, primojel, calcium CMC, corn starch and Avicel PH102. The initial rate of moisture sorption was important for the disintegration capacity as well as hydration capacity. The effect of storage at different temperatures and relative humidity upon the tablets containing various disintegrants was evaluated in terms of tablet hardness and disintegration time. Storage at high temperature reduced the hardness substantially and retarded the disintegration of the all tablets studied. Especially, the hardness of tablets containing Kollidon CL was significantly reduced. Although the tablet hardness was decreased and the disintegration time was increased under a moderate humid condition, both of them were decreased under the severely high humid condition of 80 or 90% RH, which was due to the breakrupture of tablet matrix bonds by the excessive uptake of moisture. Therefore, the stability caused by moisture sorption should be considered, when disintegrants having high moisture sorption such as Kollidon CL, Ac-Di-Sol and Primojel were employed in the tablets containing water-labile or hygroscopic drugs.

• 펄프종이기술
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• 제34권3호
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• pp.17-24
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• 2002

An unsteady-state moisture diffusion through cellulosic fibers in paper was characterized from the moisture sorption experiment and the mathematical modeling. The sorption experiment was conducted by exposing thin dry paper specimens to a constant temperature-humidity environment. Oven dried blotting papers and filter papers were used as test samples and the gains of their weights were constantly monitored and recorded as a function of sorption time. For a mathematical approach, the moisture transport was assumed to be an one-dimensional diffusion in thickness direction through the geometrically symmetric structure of paper. The model was asymptotically simplified with a short-term approximation. It gave us a new insight into the moisture uptake phenomena as a function of square root of sorption time. The fiber-phase moisture diffusivities(FPMD) of paper samples were then determined by correlating the experimental data with the unsteady-state diffusion model obtained. Their values were found to be on the order of magnitude of $10^{-6}-10^{-7}cm^2$/min., which were equivalent to the hypothetical effective diffusion coefficients at the limit of zero porosity. The moisture sorption curve predicted from the model fairly agreed with that obtained from the experiment at some limited initial stages of the moisture uptake process. The FPMD value of paper significantly varied depending upon the current moisture content of paper. The mean FPMD was about 0.7-0.8 times as large as the short-term approximated FPMD.