• Title/Summary/Keyword: Moisture Release

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Formulation and Evaluation of Moisture-activated Acyclovir Patches (수분 감응성 아시클로버 패취제의 설계 및 평가)

  • Kim, Ah-Mee;Gwak, Hye-Sun;Chun, In-Koo
    • Journal of Pharmaceutical Investigation
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    • v.36 no.6
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    • pp.393-399
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    • 2006
  • This study was aimed to design, formulate and characterize the moisture-activated patches containing acyclovir for antiviral action. Gel intermediates for film-type patches were prepared with mucoadhesive polymer, viscosity builders, enhancers and acyclovir. Patches containing acyclovir were characterized by in vitro measurement of drug release rates through a cellulose barrier membrane, and of drug flux through the hairless mouse skin. Film-type patches obtained were uniform in the thickness and showed a mucoadhesive property when contacted with moisture. The formulation was optimized, which consisted of $Cantrez^{\circledR}$ AN-169(2%), $Kollidon^{\circledR}$ VA 64(1%), $Natrosol^{\circledR}$(1%), hydroxypropyl-$\beta$-cyclodextrin(1%) and dimethylsulfoxide(0.5%). Release rates of acyclovir patches increased dose-dependently. The addition of terpenes such as d-limonene or cineole increased release rates of acyclovir, but decreased permeation rates. The permeation rates were enhanced by 2 and 2.5 times by the addition of glycyrrhizic acid ammonium salt and sodium glycocholate, respectively, compared with that of no enhancer. These results suggest that it may be feasible to deliver acyclovir through the skin or gingival mucosa from the moisture-activated patches.

The Effect of Thermal Storage/Release and Moisture Transport Properties of Polyethylene Glycol-Treated Acrylic Athletic Socks on the Wear Performance (Polyethylene Glycol 처리한 아크릴 운동용 양말의 축열 . 방열성과 수분전달 특성이 착용 성능에 미치는 영향)

  • 조길수;이은주
    • Journal of the Korean Society of Clothing and Textiles
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    • v.19 no.1
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    • pp.36-50
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    • 1995
  • The purpose of this study was 1) to estimate the improvement of thermal storage/release and moisture transport properties of PEG-treated acrylic athletic socks and suggest the optimum add-on for PEG treatment, 2) to investigate wear performance of untreated cocks and two kinds of socks treated with PEG of minimum and optimum add-on respectively, and 3) to consider the effect of thermal storage/release and moisture transport properties of PEG- treated socks on the wear performance and the subjective comfort zone. Thermal activities of specimens treated by PDC were evaluated on a DSC by measuring the heat of fusion on heating and the heat of crystallization on cooling. Moisture regain, absorption speed, wickability, water retenti on value, and water-vapor permeability were measured. In the wear trials that the subjects performed a subsequent exercise protocol wearing three differently treated socks in a conditioned environment ($14\pm2^{\circ}C$, 65$\pm$2% R.H.), microclimate temperature and humidity, and subjective wear sensations including thermal sensation, wettedness, softness, fit, and overall comfort were obtained. PEC-treated specimens with more than 20% add-on showed thermal storage on heating and thermal release on cooling by a DSC and the heat contents of treated ones were generally proportional to the add-ons. Moisture transport properties were highly improved after PEG treatment and increased rapidly with increasing add-on. The tendencies were, however, relaxed above 50% add-on and the treated knits were much stiffer above that add-on. In the wear trials of untreated, PEG add-on 20%, and 50% acrylic socks, the changes of microclimate temperature of 50% socks were significantly less than that of 20% socks. PEG add-on 50% socks showed significantly less changes of microclimate humidity than other two kinds of socks. Three kinds of socks showed significant differences in overall comfort and add-on 50% socks were accepted more comfortable than other two kinds of socks. Comfort zone of foot was extended after PEG treatment on socks and it implied that the subjects wearing PEG- treated socks felt comfortable in wider ranges of microclimate temperature and humidity.

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Numerical Study on the Discharge of Humidity in the Drum of a Washing Machine (세탁기 드럼 내부의 습기 방출 메커니즘에 대한 수치 연구)

  • Jung, Chung-Hyo;Sohn, Deok-Young;Na, Seon-Uk;Choi, Yun-Ho
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.25 no.1
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    • pp.54-61
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    • 2016
  • Washing machine manufacturers typically advise consumers to maintain the relative humidity in the drum less than 80% for three days after the termination of a washing cycle in order to prevent bacteria proliferation. A vent installed in the back of a washing machine is used to release moisture to satisfy this condition. Up to now, the design and installation of the vent have been based on experiments without understanding its roles and physical phenomena. In this study, various CFD results are presented in order to explain the physical mechanism of moisture release in a washing machine. Two methods of moisture release (diffusion and convection) were studied; diffusion was found to be the dominant process in removing moisture. Experiments were also performed to validate this behavior. In addition, this study will aid in the efficient design of vents to keep the relative humidity low inside the drum.

Effect of Alternating Vacuum and Release Process on Drying Characteristics of Log Cross Section during Radio Frequency Drying

  • Xie, Dan;Lee, Nam-Ho;Chang, Yoon-Seong;Yeo, Hwanmyeong
    • Journal of the Korean Wood Science and Technology
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    • v.41 no.5
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    • pp.456-465
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    • 2013
  • Log cross sections of yellow poplar were dried in a radio frequency vacuum (RFV) dryer under alternating vacuum and release (AVR) process. The average moisture content (MC), temperature and vapor pressure at the volumetric center were monitored as functions of time. Three different log thicknesses (33, 60 and 75mm) were tested. The results show that the AVR process caused an increase in the drying rate when the moisture content was above fiber saturation point (FSP, about 30% MC) but that it had an inverse effect on the drying rate when the MC was below FSP. The effect of the AVR process on the drying rate decreased, and the severity of heart checks increased, with the increase in the thickness of the specimens.

The Characteristics of Combustion for Living Leaves in Quercus variabilis with Monthly Seasonal Variations (굴참나무 생엽의 월별 연소특성에 관한 연구)

  • Park, Young-Ju;Oh, Jin-Youl;Lee, Si-Young;Lee, Hae-Pyeong
    • Journal of the Korean Society of Hazard Mitigation
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    • v.10 no.3
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    • pp.85-90
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    • 2010
  • In this study, we have examined the monthly combustion characteristics of Quercus variabilis, a representing Quercus Spp. in Korea, using its living leaves over the period of from June to October. As a result, we were able to identify that their moisture content was about 114%~155%. The leaves of Quercus variabilis collected in October showed the lowest moisture content and nonflaming ignition temperature. The leaves of July showed the fastest flaming ignition time of 27s while those from September showed the longest persistence of flame with 105s, and also showed the highest total heat release amount. There was a noticeable difference in each month of the above period regarding total heat release amount and total smoke release amount with a gradual increase from June to October. The maximum smoke density was a bit higher in October leaves but there was no significant monthly difference. In addition, July leaves were shown to reach the maximum value in the shortest time of 795s.

Preparation and Physical Characteristics of High-Performance Heat Storage.Release Fabrics with PCMMc : Wet coating process (상전이 마이크로캡슐이 함유된 고기능성 축열.발열 직물의 제조 및 물리적 특성 : 습식코팅)

  • Koo, Kang;Choe, Jong-Deok;Choi, Jong-Suk;Kim, Eun-Ae;Park, Young-Mi
    • Textile Coloration and Finishing
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    • v.19 no.1 s.92
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    • pp.24-30
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    • 2007
  • Heat storage/release system in textile is a useful tool to increase energy efficiency and enhance comfortable microclimate of clothing. Phase change materials(PCM) are used in regulating storage and release properties of thermal energy. To investigate the temperature regulating ability of fabrics with PCM microcapsule(PCMMc), Nylon fabrics were coated with PCMMc via wet processing and they were characterized by SEM, DSC and infrared thermal analyzer. Also, water moisture transpiration, water penetration resistance, peel strength and washing durability of the fabrics were assessed. The water vapor permeation and water penetration resistance decreased with increasing PCMMc content. In DSC analysis, it can be seen that the microencapsulated fabric showed both exothermic md endothermic phenomena at specific temperature. Peel strength was decreased with increasing PCMMc content.

Synthesis of CM-Chitin from Crab Shells (게껍질로부터 CM-Chitin의 합성)

  • Ahn, C.I.;Kim, S.H.;Yoo, Y.J.;Park, C.H.;Lim, H.S.;Park, C.K.;Park, E.K.
    • Journal of the Korean Applied Science and Technology
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    • v.10 no.2
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    • pp.41-47
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    • 1993
  • Chitin was isolated from crab shells by modified Hackman's method, which was treated again with aqueous sodium hydroxide solution to give alkali chitin(sodium alkoxide of chitin). And after, the alkali chitin is allowed to react with monochloroacetic acid to synthesize 6-O-(carboxymethyl) chitin [CM-Chitin] under diminished pressure. In order to synthesize high performance CM-Chitin as hygroscopic agent, it was measured that the yield and degree of subsititution of each CM-Chitin according to molar ratio(monochloroacetic acid equivalent mol/N-acetyl-D-glucosamine residue) and their moisture-absorption and moisture-release properties were measured and compared with those of hyaluronic acid. The moisture-absorption and moisture-release properties of CM-Chitin, especially 0.8 in degree of substitution, were found quite similar to those of hyaluronic acid. The preliminary results show that CM-Chitin might be used as hygroscopic agent instead of hyaluronic acid in field of cosmetics.

Preparation and Characterization of Calcium Alginate Microcapsules by Emulsification-Internal Gelation (에멀션-내부 젤화에 의한 알긴산 칼슘 마이크로캡슐의 제조 및 특성)

  • Park Soo-jin;Kang Jin-Young
    • Polymer(Korea)
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    • v.29 no.4
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    • pp.369-374
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    • 2005
  • In this work, the calcium alginate microcapsules containing lemon oil were prepared by emulsification-internal gelation and their potential use as aromatherapy was examined by the controlled release system. The lemon oil encapsulated in the alginate was successfully observed by Fourier transform (FT-IR) spectroscopy and differential scanning calorimeter (DSC) measurements. Analysis of the diameters and shapes of microcapsules was conducted by scanning electron microscopy (SEM). The mean diameters ranging from 4 to 7 um and encapsulation yield ranging from 50 to $85\%$ were obtained. The controlled release of the lemon oil at $37^{circ}$ was demonstrated by the infrared moisture determination (IMDB). It was found that the amount of released lemon oil decreased with increasing concentrations of alginate and $CaCl_2$ due to the higher the cross-linking density of the capsules prepared. The oil release from the capsule was measured as a function of physical force. We confirmed that the external factor could control the collapse of capsule wall and the release rate.

Development of Definition of Parameters and Reference Scales for Texture Profiling of Frankfurter Sausages (소세지의 텍스처 프로필 수행을 위한 용어와 표준척도의 개발)

  • Kim, Hye-Young;Lee, Mi-Gyung;Jang, Kyung-Ah;Kim, Kwang-Ok
    • Korean Journal of Food Science and Technology
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    • v.27 no.1
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    • pp.1-5
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    • 1995
  • The texture profile of frankfurter sausages was carried out by comparing the domestic(A) and imported(B) products. Fourteen character notes were identified: elasticity, surface moisture, surface smoothness, center hardness, skin toughness, cohesiveness, denseness, chewiness, moisture release, cohesiveness of mass, lumpiness, graininess, skin separation, and oiliness. Reference scales and the $0{\sim}3$ point numerical scaling method were also established. Panelists evaluated sausage A harder than the sausage B. It had higher skin separation and elasticity scores requring more chewing. Sausage B had lower surface moisture and cohesiveness of mass, but higher moisture release and graininess. Panelists commented that the sausage B were oilier but had milder tastes.

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Managing Red Oak (Quercus rubra L.) Reduces Sensitivity to Climatic Stress

  • Chhin, Sophan
    • Journal of Forest and Environmental Science
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    • v.34 no.4
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    • pp.338-351
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    • 2018
  • This study was conducted in a long-term experimental forest in the central hardwoods region of southwestern Michigan to retrospectively examine the role of past forest management practices and climate on red oak (Quercus rubra L.) productivity. Initially, in 1971, plots within the experimental forest were treated separately with a clearcut and shelterwood regeneration harvest in an attempt to increase red oak regeneration. From 1987-1989, a new study was initiated within a portion of the clearcut and shelterwood plots to evaluate the effectiveness of additional oak crop tree release using mechanical and chemical applications. Cumulative diameter and mortality rates of 719 red oaks were monitored across the four silvicultural treatments: Clearcut-A (clearcut without additional release treatment), Clearcut-B (clearcut with additional release treatment), Shelterwood-A (shelterwood without additional release), and Shelterwood-B (shelterwood with additional release) plus an untreated control. Increment cores were obtained from red oak trees and neighboring competitor species. Tree-ring analyses (dendrochronology) were applied to examine the effect of these silvicultural treatments and climatic factors (temperature and precipitation) on red oak productivity. The results indicated that crop tree release following a clearcut or shelterwood harvest reduced mortality rates and thus increased survival of red oak. Red oak in control plots or plots only receiving the initial regeneration harvesting treatment and no additional competition release were negatively affected by climatic stress, which included summer moisture stress. In contrast, red oak in plots that received the competition release treatment from shade tolerant tree species not only had higher tree level productivity (i.e., tree basal area) and lower mortality rates, but were also relatively more resilient to climatic stress by showing limited or no associations between climate and growth.