• Title/Summary/Keyword: moisture retention

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Influence of Membrane Forming Compounds for Concrete on Water Retention Properties of Concrete Mortar (콘크리트용 피막 양생제가 시멘트 모르타르의 보습특성에 미치는 영향)

  • Lee, Gun-Cheol;Noh, Sang-Kyun;Cho, Byoung-Young;Kim, Young-Geun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2009.11a
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    • pp.117-120
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    • 2009
  • It has been gradually increased with the use of resin based membrane forming agent for curing method, which plays a role in protecting moisture evaporation by forming resin membrane at the surface of concrete. In this paper, tests were carried out to examine moisture retention capability of cement mortar applying membrane forming agent. Dosages and types of the membrane forming agent were varied. It is found that sheet curing sealed with the surface of concrete closely has favorable moisture retention capability. However, the application of membrane forming curing method had superiority in moisture retention capability at early stage but at later age, its capability is deteriorated. Hence, further study regarding altering application method was necessary to secure enhanced moisture retention capability.

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SPATIAL AND TEMPORAL INFLUENCES ON SOIL MOISTURE ESTIMATION

  • Kim, Gwang-seob
    • Water Engineering Research
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    • v.3 no.1
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    • pp.31-44
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    • 2002
  • The effect of diurnal cycle, intermittent visit of observation satellite, sensor installation, partial coverage of remote sensing, heterogeneity of soil properties and precipitation to the soil moisture estimation error were analyzed to present the global sampling strategy of soil moisture. Three models, the theoretical soil moisture model, WGR model proposed Waymire of at. (1984) to generate rainfall, and Turning Band Method to generate two dimensional soil porosity, active soil depth and loss coefficient field were used to construct sufficient two-dimensional soil moisture data based on different scenarios. The sampling error is dominated by sampling interval and design scheme. The effect of heterogeneity of soil properties and rainfall to sampling error is smaller than that of temporal gap and spatial gap. Selecting a small sampling interval can dramatically reduce the sampling error generated by other factors such as heterogeneity of rainfall, soil properties, topography, and climatic conditions. If the annual mean of coverage portion is about 90%, the effect of partial coverage to sampling error can be disregarded. The water retention capacity of fields is very important in the sampling error. The smaller the water retention capacity of the field (small soil porosity and thin active soil depth), the greater the sampling error. These results indicate that the sampling error is very sensitive to water retention capacity. Block random installation gets more accurate data than random installation of soil moisture gages. The Walnut Gulch soil moisture data show that the diurnal variation of soil moisture causes sampling error between 1 and 4 % in daily estimation.

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Potential Water Retention Capacity as a Factor in Silage Effluent Control: Experiments with High Moisture By-product Feedstuffs

  • Razak, Okine Abdul;Masaaki, Hanada;Yimamu, Aibibula;Meiji, Okamoto
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.4
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    • pp.471-478
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    • 2012
  • The role of moisture absorptive capacity of pre-silage material and its relationship with silage effluent in high moisture by-product feedstuffs (HMBF) is assessed. The term water retention capacity which is sometimes used in explaining the rate of effluent control in ensilage may be inadequate, since it accounts exclusively for the capacity of an absorbent incorporated into a pre-silage material prior to ensiling, without consideration to how much the pre-silage material can release. A new terminology, 'potential water retention capacity' (PWRC), which attempts to address this shortcoming, is proposed. Data were pooled from a series of experiments conducted separately over a period of five years using laboratory silos with four categories of agro by-products (n = 27) with differing moisture contents (highest 96.9%, lowest 78.1% in fresh matter, respectively), and their silages (n = 81). These were from a vegetable source (Daikon, Raphanus sativus), a root tuber source (potato pulp), a fruit source (apple pomace) and a cereal source (brewer's grain), respectively. The pre-silage materials were adjusted with dry in-silo absorbents consisting wheat straw, wheat or rice bran, beet pulp and bean stalks. The pooled mean for the moisture contents of all pre-silage materials was 78.3% (${\pm}10.3$). Silage effluent decreased (p<0.01), with increase in PWRC of pre-silage material. The theoretical moisture content and PWRC of pre-silage material necessary to stem effluent flow completely in HMBF silage was 69.1% and 82.9 g/100 g in fresh matter, respectively. The high correlation (r = 0.76) between PWRC of ensiled material and silage effluent indicated that the latter is an important factor in silage-effluent relationship.

Preparation of Lip Balm Utilizing Functionalities of Colorants Extracted from Marine Algae (해조류 추출색소의 기능성을 활용한 립밤 제조)

  • Choi, Min;Yoo, Dong Il;Shin, Younsook
    • Textile Coloration and Finishing
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    • v.26 no.2
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    • pp.124-130
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    • 2014
  • The aim of this study is to utilize the algae extracts with functionalities such as antioxidant and antimicrobial properties for preparing lip balm. Functional properties of extracts from Dictyota coriacea and Ulva pertusa were evaluated in terms of DPPH radical scavenging activity and antimicrobial activity. Lip balms contained the algae extracts were tested its efficacy by measuring the moisture retention of lip skin after applying human subjects. According to the results of skin moisture retention measurement, lip balm was effective to increase the moisture retention of lip skin. It is considered that the utilization of colorants extracted from algae which are verified of antioxidant effect and antimicrobial activity is valuable and useful in developing the cosmetic products.

A Study of Soil Moisture Retention Relation using Weather Radar Image Data

  • Choi, Jeongho;Han, Myoungsun;Lim, Sanghun;Kim, Donggu;Jang, Bong-joo
    • Journal of Multimedia Information System
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    • v.5 no.4
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    • pp.235-244
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    • 2018
  • Potential maximum soil moisture retention (S) is a dominant parameter in the Soil Conservation Service (SCS; now called the USDA Natural Resources Conservation Service (NRCS)) runoff Curve Number (CN) method commonly used in hydrologic modeling for event-based flood forecasting (SCS, 1985). Physically, S represents the depth [L] soil could store water through infiltration. The depth of soil moisture retention will vary depending on infiltration from previous rainfall events; an adjustment is usually made using a factor for Antecedent Moisture Conditions (AMCs). Application of the method for continuous simulation of multiple storms has typically involved updating the AMC and S. However, these studies have focused on a time step where S is allowed to vary at daily or longer time scales. While useful for hydrologic events that span multiple days, this temporal resolution is too coarse for short-term applications such as flash flood events. In this study, an approach for deriving a time-variable potential maximum soil moisture retention curve (S-curve) at hourly time-scales is presented. The methodology is applied to the Napa River basin, California. Rainfall events from 2011 to 2012 are used for estimating the event-based S. As a result, we derive an S-curve which is classified into three sections depending on the recovery rate of S for soil moisture conditions ranging from 1) dry, 2) transitional from dry to wet, and 3) wet. The first section is described as gradually increasing recovering S (0.97 mm/hr or 23.28 mm/day), the second section is described as steeply recovering S (2.11 mm/hr or 50.64 mm/day) and the third section is described as gradually decreasing recovery (0.34 mm/hr or 8.16 mm/day). Using the S-curve, we can estimate the hourly change of soil moisture content according to the time duration after rainfall cessation, which is then used to estimate direct runoff for a continuous simulation for flood forecasting.

Moisture Sorption Isotherm and Quality Deterioration of Dry Jujube (건대추의 등온흡습곡선 및 품질열화특성)

  • 김영숙;안덕순
    • Food Science and Preservation
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    • v.4 no.1
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    • pp.33-38
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    • 1997
  • In order to provide informations for designing packaging and storage condition of dry jujube (Zizyphus jujuba MILLER), moisture sorption isotherm was determined for temperatures of 20, 30 and 4$0^{\circ}C$, and quality changes were evaluated as function of temperature and water activity. Dry jujube at a given water activity showed higher equilibrium moisture content for lower temperature. Moisture isothem could be fitted by GAB model equation, giving higher C value, lower m0 and relatively constant k value with increase in temperature. Ascorbic acid was lost more highly at higher temperature and water activity, and showed negligible retention for whole range of water activity and temperature studied after 141 days. Browning increased with water activity up to 0.73 at 30 and 4$0^{\circ}C$. Dry jujube of high water activity had high L value in surface color, which represent brightness of surface color. Considering quality retention in the storage, dry jujube is desired to be dried to water activity of 0.42 and be stored at temperature below 3$0^{\circ}C$

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Effects of Cooking Method on the Vitamin and Mineral Contents in Frequently Used Vegetables (조리 방법이 상용채소의 비타민 및 무기질 함량에 미치는 영향 -시금치, 양배추, 콩나물, 당근을 중심으로 -)

  • Chung, Hae Kyung;Yoon, Kyung-soo;Woo, Nariyah
    • Korean journal of food and cookery science
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    • v.32 no.3
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    • pp.270-278
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    • 2016
  • Purpose: We have investigated for the purpose of studying change of vitamins and minerals in frequently used vegetables by low moisture cooking method. Methods: Vitamin B complex, vitamin C and mineral (Mg, Ca, K, Zn, Fe) contents are analyzed in vegetables such as spinach, cabbage, bean sprouts and carrot which are heat-treated with degrees of water contents. Low moisture cooking method represents heat-treated vegetable (LM experiment group) with 25 wt.% water content for the vegetable weight while general blanching method includes heat-treated vegetable (GB experiment group) with 500-1,000 wt.% water content for the vegetable weight. Results: Retention rate of vitamin B1 (thiamin) in the LM experiment group is relatively high (87.50-95.68%) and dosen't show considerable differences from raw vegetables. On the other hand, the retention rate of vitamin $B_1$ in GB group's cabbage and spinach dramatically decreased to 19.46-25.00%. Retention rate of vitamin B2 (riboflavin) is sustained stably in LM experiment group (75.00-87.50% in bean sprouts, cabbage and spinach), represents that low moisture cooking method has relatively higher contents in vitamin $B_2$. The LM experiment group has 71.43-85.71% on retention rate of niacin while the GB group shows relatively lower niacin (57.14-64.58%), represents conflicting results from the general idea that vitamin $B_3$ is relatively stable in heat treatment and blanching. Retention rate of pantothenic acid is considerably higher in both LM and GB experiment group, indicates vitamin pantothenic acid is relatively stable in the various cooking condition such as amount of water and heat treatment. In the experiment under various water contents, vitamin C is not detected in both bean sprouts and carrots, while the contents in cabbage and spinach are 19.87 mg/100 g and 26.65 mg/100 g respectively. In the same experiment, the retention rate of Vitamin C in LM experiment group (91.65%, 92.23%) is considerably higher than GB group (58.08%, 61.61%). Retention rate of Mg, K, Fe in the LM experiment group is relatively higher than GB group. Conclusion: Resultingly, the observations suggests that minimum water quantity and minimum heat treatment processes should be established in cooking vegetables which have soluble vitamins and minerals.

Effect of Cations on the Sorption and the Tensile Properties of CMC Fibers (CMC섬유내의 양이온이 섬유의 흡습성과 인장 성질에 미치는 영향)

  • 이미식
    • Journal of the Korean Society of Clothing and Textiles
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    • v.18 no.1
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    • pp.113-120
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    • 1994
  • The Purpose of this study was to improve the moisture related properties of viscose rayon fibers. Viscose rayon filament yarns were partially etherified to make CMC fibers. CMC fibers were converted to the sodium, calcium, and ferric salt forms by an ion exchange method. The property changes of ion exchanged CMC fibers were examined. Cation contents of fibers were varied depending on the degree of substitution of CMC fibers. The strength of Na, Ca, Fe-CMC was higher than H-CMC owing to the plasticization by moisture sorption and the crosslinking by cations. The moisture regain was increased by carboxymethylation and that of Fe-CMC showed the highest value. The degree of swelling determined by the water retention value was observed to be Na-CMC > Ca-CMC > H-CMC > Fe-CMC. The solution retention value was decreased in the order . Ca-CMC > Na-CMC > H-CMC > Fe-CMC.

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Applications of Panax ginseng leaves-mediated gold nanoparticles in cosmetics relation to antioxidant, moisture retention, and whitening effect on B16BL6 cells

  • Jimenez-Perez, Zuly Elizabeth;Singh, Priyanka;Kim, Yeon-Ju;Mathiyalagan, Ramya;Kim, Dong-Hyun;Lee, Myoung Hee;Yang, Deok Chun
    • Journal of Ginseng Research
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    • v.42 no.3
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    • pp.327-333
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    • 2018
  • Background: Bioactive compounds in plant extracts are able to reduce metal ions to nanoparticles through the process of green synthesis. Panax ginseng is an oriental medicinal herb and an adaptogen which has been historically used to cure various diseases. In addition, the P. ginseng leaves-mediated gold nanoparticles are the value-added novel materials. Its potential as a cosmetic ingredient is still unexplored. The aim of this study was to evaluate the antioxidant, moisture retention and whitening properties of gold nanoparticles (PgAuNPs) in cosmetic applications. Methods: Cell-free experiments were performed to evaluate PgAuNP's antioxidant and moisture retention properties and inhibition activity on mushroom tyrosinase. Furthermore, in vitro cell cytotoxicity was evaluated using normal human dermal fibroblast and murine B16BL6 melanoma cells (B16) after treatment with increasing concentrations of PgAuNPs for 24 h, 48 h, and 72 h. Finally, in vitro cell assays on B16 cells were performed to evaluate the whitening effect of PgAuNPs through reduction of cellular melanin content and tyrosinase activity. Results: In vitro DPPH radical scavenging assay results revealed that PgAuNPs exhibited antioxidant activity in a dose-dependent manner. PgAuNPs exhibited moisture retention capacity and effectively inhibited mushroom tyrosinase. In addition, 3-(4,5-dimethyl-thiazol-2yl)-2,5-diphenyl tetrazolium bromide results revealed that PgAuNPs were not toxic to human dermal fibroblast and B16 cells; in addition, they significantly reduced melanin content, tyrosinase activity, and mRNA expression of melanogenesis-associated transcription factor and tyrosinase in B16 cells. Conclusion: Our study is the first report to provide evidence supporting that P. ginseng leaves-capped gold nanoparticles could be used as multifunctional ingredients in cosmetics.

Analysis of Regional Antecedent Wetness Conditions Using Remotely Sensed Soil Moisture and Point Scale Rainfall Data (위성토양수분과 지점강우량을 이용한 지역 선행습윤조건 분석)

  • Sunwoo, Wooyeon;Kim, Daeun;Hwang, Seokhwan;Choi, Minha
    • Korean Journal of Remote Sensing
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    • v.30 no.5
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    • pp.587-596
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    • 2014
  • Soil moisture is one of the most important interests in hydrological response and the interaction between the land surface and atmosphere. Estimation of Antecedent Wetness Conditions (AWC) which is soil moisture condition prior to a rainfall in the basin should be considered for rainfall-runoff prediction. In this study, Soil Wetness Index (SWI), Antecedent Precipitation Index ($API_5$), remotely sensed Soil Moisture ($SM_{rs}$), and 5 days ground Soil Moisture ($SM_{g5}$) were selected to estimate the AWC at four study area in the Korean Peninsula. The remotely sensed soil moisture data were taken from the AMSR-E soil moisture archive. The maximum potential retention ($S_{obs}$) was obtained from direct runoff and rainfall using Soil Conservation Service-Curve Number (SCS-CN) method by rainfall data of 2011 for each study area. Results showed the great correlations between the maximum potential retention and SWI with a mean correlation coefficient which is equal to -0.73. The results of time length representing the time scale of soil moisture showed a gap from region to region. It was due to the differences of soil types and the characteristics of study area. Since the remotely sensed soil moisture has been proved as reasonable hydrological variables to predict a wetness in the basin, it should be continuously monitored.