• Title/Summary/Keyword: PROPYLENE GLYCOL

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The Effects of Cd particle size on the Properties of Cds/CeTe Solar Cells (Cd 입도 크기가 CdS/CdTe 태양전지의 특성에 미치는 영향)

  • Im, H.B.;Roh, J.S.
    • Proceedings of the KIEE Conference
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    • 1987.11a
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    • pp.200-202
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    • 1987
  • Sintered CdS films on glass substrate with low electrical resistivity and high optical transmittance have been prepared by coating and sintering method. All-polycrystalline CdS/CdTe solar cells with different microstructure and properties of CdTe layer were fabricated by coating a number of CdTe slurries, which consisted of Cd and Te powders, an appropriate amount of propylene glycol and 2 or 7.5 w/o $CdC1_2$, on the sintered CdS films and by sintering the glass-CdS-(Cd+Te) composites at various temperature. To explore the dependence of the solar efficiency on the preparation conditions of the CdTe layer, Cd powder with an average particle size of $0.3{\mu}m$ or $5{\mu}m$ was prepared. The use of Cd with finer particles forms more dense or uniform microstructure of the nuclear of CdTe during the heating. Therefore the use of Cd with finer particles improves the efficiency of the sintered CdS/CdTe solar cell by improving the microstructure of sintered CdTe layer. But the difference of solar efficiency by varing a particle size of Cd is decreased with increasing amount of $CdC1_2$ in the (Cd+Te) layer. All-polycrystalline CdS/CdTe solar cells with an efficiency of 10.2% under solar irradiation have been fabricated using a Cd with finer particles.

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Effect on Ice Slurry Flowing in the Elbow of Various Angle (다양한 각도의 곡관 내에서 아이스슬러리의 유동에 따른 영향)

  • 김규목;박기원;권일욱
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.16 no.2
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    • pp.142-149
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    • 2004
  • Recently, the government introduced the thermal storage system for reducing the electric power load. Especially, the ice slurry type has gained lots of interest due to its good heat transfer and flowing characteristics. This study was peformed to understand the effects of transporting ice slurry through elbows of various angle. Propylene glycol water solution was used and about 2 mm ice particles were circulated. The experiments were carried out under various conditions, such as concentration and velocity of water solution ranging between 0∼20 wt%, 1.5∼2.5 m/s, respectively. And elbows with 4 different angles of 30$^{\circ}$, 45$^{\circ}$, 90$^{\circ}$, 180$^{\circ}$. The differential pressure and IPF (ice packing factor) between the pipe entry and exit were measured. The tendency of pressure loss and outlet IPF in elbow is that the pressure loss was reduced as concentration and flow velocity of water solution is increased, and low value appeared at 10 wt% and 2.5 m/s. The variation of outlet IPF was compared with the inlet IPF in the range of $\pm$20%.

Ketorolac Ester Enhancer-prodrugs: Preparation and Evaluation of Their Physicochemical Properties

  • Yun, Sung-Il;Kim, Jung-Sun;Yong, Chul-Soon
    • Journal of Pharmaceutical Investigation
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    • v.38 no.6
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    • pp.405-412
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    • 2008
  • Six ester analogues of Ketorolac were synthesized as potential enhancer prodrugs for transdermal delivery. Solubility of these esters was determined in 10% propylene glycol (PG)/isotonic phosphate buffer (IPB) at room temperature while lipophilicity was obtained as partition coefficients (log P) and capacity factors (k') using HPLC. Stability of the prodrugs in skin extract and in plasma was investigated at $37^{\circ}C$. The lipophilicity of the potential prodrugs increased in proportion to their alkyl chain length. Good linear relationship between partition coefficients (log P) and capacity factors (log k') was observed ($R^2=0.9961$). All of the analogues were fairly stable but slowly degraded in IPB over a 12 hour period. However, their stability in skin extract and in plasma varied with most compounds gradually decomposing over a 12 hour period. Although unsaturation of the alkyl ester chain did not alter the over all lipophilicity of the compound, the half-life was significantly affected. In plasma, degradation of the esters was slower than in the skin extract, which is a desirable trait for enhancer-prodrugs. However, the overall hydrolysis in the skin extract needs to be facilitated for the development of an effective enhancer prodrug. The analogue with the shortest half life in the skin extract was the unsaturated C-12 analogue of 0.96 hr.

A Study on the Characteristics of Liquid Body Foam Which Added the Garlic Extract (갈릭 추출물을 첨가한 액상 바디 폼의 특성에 관한 연구)

  • Sung, Ki-Chun;Ahn, Beom-Shu
    • Journal of the Korean Applied Science and Technology
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    • v.18 no.4
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    • pp.285-291
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    • 2001
  • The liquid body foam which added the garlic extract, differs for clothes and kitchen detergent, industrial and domestic detergent, and it has various characteristics as a soft detergent for bath and hair product. The contents of various characteristics in this experiment have tested for the foam formation force, the moisture force and the antimicrobial force. In case of this product adding garlic extrat, we could know the three characteristics. In first case to increase the concentration of Sunfom-S, we could know that the foam formation force increases following to it. In second case to increase the concentration of propylene glycol, we could know that the moisture force increases following to moisturing agent. In third case to increase the concentration of garlic extract, we could know that the antibiosis and preservation efficacy appears between 3.0-4.0wt% and the sterilization efficacy appears more than 5.0wt%. According to the result of this experiment, we could recognize the characteristics concerning to quality of this product.

Numerical Simulation of the Odor Spreading in a Factory (공장에서 퍼지는 냄새에 관한 수치계산적 연구)

  • Vincent, Lijo;Song, Eun-Hwa;Nam, Hyun-Kyu;Shin, Choon-Sik;Kim, Heuy-Dong
    • Proceedings of the KSME Conference
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    • 2008.11b
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    • pp.2540-2543
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    • 2008
  • Liquid crystal displays (LCD's) are continuously coated with some chemicals in the clean room of a factory. Spreading of these chemicals is causing serious problems both in controlling clean room quality as well as to the workers inside the factory. It is required to alleviate or properly control the offensive odor which is mainly composed of propylene glycol mono ethyl acetate, novolak resin and photo active compound. The control strategy employed is to bleed the offensive odor gas out the clean room. A full scale 3D CFD model was created with anisotropic porous media, chemical species transport with no volumetric reaction, and thermal diffusion with propane gas (tracer gas) to simulate the odor spreading. A segregated implicit solver with standard k-$\varepsilon$ model is employed. The detailed CFD analysis made it possible to develop an effective method of ventilating the coater room and optimizing their capacities.

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Variation of Pressure Loss and IPF Flowing Ice Slurry in Straight Tube Inclined to Various Angle (다양한 각도로 기울어진 직관내에서 아이스슬러리 유동시 압력손실과 IPF 변화)

  • Kim Kyu-Mok;Park Ki-Won
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.16 no.11
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    • pp.1028-1034
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    • 2004
  • Recently, the ice storage system using ice slurry has been used increasingly since it has been introduced where the rapid cooling load change is required. Because it overcomes a decrease of the melting performance and an increase of the thermal resistance on the ice layer in static ice thermal storage system. This study is performed to understand the effects of transporting ice slurry through horizontal, vertical and inclined tubes ($30^{\circ},\;45^{\circ}$). It used propylene glycol-water solution and ice particles (diameter of about 2 mm) in this experiment. The experiments were carried out under various conditions, with concentration of water solution ranging from 0 to $20wt\%$, and velocity of water solution at the entry ranging from 1.5 to 2.5 m/s. The results were as follows: Regarding the angle of inclined tube, the highest pressure loss was measured for vertical tube and the pressure loss for $45^{\circ},\;30^{\circ}$, horizontal straight tubes were lower successively. The lowest pressure loss in these tubes was measured at velocity of $2.0{\sim}2.5m/s$ and concentration of $10wt\%$. The outlet IPF was likewise stable in these ranges.

A Study of the relationship between partition coefficients of oils and antimicrtobial effects (파라벤류에 대한 오일의 분배계수와 실제 방부력과의 상관관계 연구)

  • 한종섭;김종일
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.21 no.2
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    • pp.94-111
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    • 1995
  • In this study, the relationship between partition coefficients(Kw) of oils and antimicrobial effects Ivas investigated. The antimicrobial activity of paraben has been known to be controlled by the concentration of the paraben in the aqueous phase. The concentration of paraben in the aqueous phase was measured by the UV/VIS spectrophotometer at the wavelength of 256nm. It was found that the hydrocarbon oils and silicone oils had the lowest Kw value(<1.0) among the tested oils. Also, the emulsions which were made of oils having low Kw values had a good antimicrobial effects. Thus, the cosmetic safety against microorganisms could be improved by using the oils which have low Kw values.

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The Preparation of Controlled-Release Microcapsules for Captopril and Their Dissolution Characteristics (제어 방출협 캅토프릴 마이크로캅셀의 제조 및 용출 특성)

  • Choi, Hyun-Soon;Ge, Jiang;Lee, Gye-Won;Jee, Ung-Kil
    • Journal of Pharmaceutical Investigation
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    • v.28 no.1
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    • pp.7-13
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    • 1998
  • The captopril microcapsules were prepared and were investigated by measuring their size distribution using Scanning Electron Microscopy(SEM) and dissolution of captopril. Cetyl alcohol microcapsules prepared by emulsion melted-cooled method with various ratios of drug to cetyl alcohol were spherical and uniform. The release rate of cetyl alcohol microcapsules was decreased proportionally as the content of cetyl alcohol increased but, the particle size of microcapsules was increased. The surface of cetyl alcohol microcapsules was comparatively rough as drug content increased. Pellet type microcapsules were prepared using fluidized-bed coating system by spraying captopril solution on nonpareil-seeds followed by applying $Eudragit^{\circledR}$ RS solution containing propylene glycol as a plasticizer. The release rate of drug from pellet type microcapsules decreased as the content of $Eudragit^{\circledR}$ RS increased.

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Iontophoretic Transport of Ketoprofen (이온토포레시스를 이용한 케토프로펜의 경피전달)

  • Kim, Jung-Ae;Oh, Seaung-Youl
    • Journal of Pharmaceutical Investigation
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    • v.34 no.4
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    • pp.275-281
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    • 2004
  • We have studied the effect of polarity, current density, current duration, crosslinking density, swelling ratio, and permeation enhancers on the transdermal flux of ketoprofen from acrylamide hydrogel. Hydrogel was prepared by free radical crosslinking polymerization of acrylamide. Drug loading was made just before transport experiment by soaking the hydrogel in solution containing drug. In vitro flux study using hairless mouse skin was performed at $36.5^{\circ}C$ using side-by-side diffusion cell, and the drug was analysed using HPLC/UV system. The result showed that, compared to passive flux, the total amount of drug transported increased about 18 folds by the application of $0.4\;mA/cm^2$ cathodal current. Anodal delivery with same current density also increased the total amount of drug transported about 13 folds. It seemed that the increase in flux was due to the electrorepulsion and the increase in passive permeability of the skin by the current application. Flux increased as current density, the duration of current application and loading amount (swelling duration) increased. As the cross linking density of the hydrogel increased, flux clearly decreased. The effect of hydrophilic enhancers (urea, N-methyl pyrrolidone, Tween 20) and some hydrophobic enhancers (propylene glycol monolaurate and isopropyl myristate) was minimal. However, about 3 folds increase in flux was observed when 5% oleic acid was used. Overall, these results provide some useful information on the design of an optimized iontophoretic delivery system of ketoprofen.

Effects of Broccoli on Anti-inflammation and Anti-oxidation According to Extraction Solvent (추출용매에 따른 브로콜리의 항산화와 항염증에 대한 효과)

  • Jang, Min-Woo;Ha, Bae-Jin
    • Journal of Food Hygiene and Safety
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    • v.27 no.4
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    • pp.461-465
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    • 2012
  • Broccoli has a functional substance, sulforaphane that has effects of anticancer, antioxidant, antimicrobial and anti-inflammatory. Sulforaphane, one of the hydrolysis products of glucoraphanin in broccoli, cabbage and kale, was contributed to the role of antioxidant. Broccoli contains a number of bioactive compounds including glucosinolates, S-methyl cysteine sulfoxide and many antioxidants. The ethanol extract (BE), hexane extract (BH), propylene glycol extract (BP) and butylenesglycol extract (BB) of broccoli were used to investigate the antioxidation and anti-inflammatory effects of sulforaphane extracts from broccoli. The high scavenging abilities of DPPH, $O_2{^-}$ were observed. Also sulforaphane extracts from broccoli showed the inhibition effect on NO rate. These results demonstrated that sulforaphane extracts from broccoli could be useful as an antioxidation and anti-inflammatory functional ingredient.