• 약학회지
• /
• 제28권6호
• /
• pp.299-303
• /
• 1984

In order to eluciate the effect of humidity and organic solvent on the decomposition of carbamide peroxide, the kinetic study was carried out. The carbamide peroxide was prepared from urea and 30%-hydrogen peroxide. The accelerated stability analysis for carbamide peroxide crystal in various relative humidity, and for 10%-carbamide peroxide solution of organic solvents were investigated. Both humidity and temperature were important factors influencing the decomposition rate of carbamide peroxide crystal. The higher the humidity and temperature, the greater was the reaction rate. The breakdown rate of crystal was observed as an apparent zero-order, and was faster than the rate of decomposition in dilute propylene glycol, glycerine or sorbitol solutioos which were measured as an apparent first-order reaction. The more dilute to 10% the organic solvents of 10%-carbamide peroxide, the slower was breakdown rate. It is, therefore, useful in the aspects of stability and economics to substitute solvent of carbamide peroxide topical solution (USP XXI) with 10%-propylene glycol or glycerine instead of anhydrous glycerine.

• 한국환경과학회지
• /
• 제12권6호
• /
• pp.635-641
• /
• 2003

A recycling process for the waste FRP from boats was developed. The recycling process is composed of decomposition of waste FRP with propylene glycol and synthesis of recycled unsaturated polyester resin from the decomposed liquid material. Prior to the decomposition, waste FRP was cut into 2cm x 5cm segments and mechanical impact was applied by press roller to give gaps between cumulated laminates. Propylene glycol effectively decomposed the waste FRP segments and glass fibers were easily separated from decomposed liquid material. Recycled unsaturated polyester resin could be made from the decomposed liquid material by reaction with maleic anhydride and phthalic anhydride.

• Journal of Pharmaceutical Investigation
• /
• 제24권1호
• /
• pp.33-40
• /
• 1994

In order to develop a broad-spectrum veterinary anthelmintic, a combined preparation of nitroxynil and levamisole was formulated for subcutaneous injection. The preformulation studies on solubilization, physicochemical stability and toxicity of combined preparation were performed. The combined preparation of nitroxynil-N-ethylglucamine and levamisole base could be solubilized up to 50.3%(w/v) of active ingredient concentration in propylene glycol/water system. Injectable solutions were most stable at $4^{\circ}C$. Local toxicities such as flare and edema were not shown when the usual dose of the combined preparation was injected subcutaneously to the rats.

• Journal of Information Display
• /
• 제13권3호
• /
• pp.107-111
• /
• 2012

An almost pure phase of $Ba_3Si_6O_{12}N_2$ doped with $Eu^{2+}$ was successfully synthesized through the ammonia nitridation of an oxide precursor prepared through an aqueous-solution method, using propylene- glycol-modified silane. The emission peak intensity of the obtained $Ba_3Si_6O_{12}N_2:Eu^{2+}$ was -2.2 times higher than that of the sample prepared through a solid-state reaction method.

• 대한치과보존학회:학술대회논문집
• /
• 대한치과보존학회 2001년도 추계학술대회(제116회) 및 13회 Workshop 제3회 한ㆍ일 치과보존학회 공동학술대회 초록집
• /
• pp.565.1-565
• /
• 2001

This study aimed to compare the efficiency of propylene glycol (PG) and distilled water (DW) as vehicles that would allow diffusion of dye through the root canal system. Human maxillary central incisors were chosen and de-crowned. After enlarging the upper part of the root canal with a Peeso reamer, cementum covering the upper third of the root was removed. The roots were ultrasonically irrigated with 5% NaOCI to remove smear layer.(omitted)

• 한국식품조리과학회지
• /
• 제20권2호
• /
• pp.133-137
• /
• 2004

This study was investigated the effects of condensed phosphates (pyrophosphate, metaphosphate and polyphosphate) on the quality and self-life of wet noodle. The initial pasting temperatures were increased by the addition of pyrophosphate and metaphosphate, respectively, whereas those of propylene glycol and polyphosphate were decreased. Pyrophosphate showed the highest final viscosity, whereas metaphosphate showed the lowest. Setback of PG, polyphosphate, pyrophosphate and metaphosphate were all lower than the control. The water absorption ratios of PG and polyphosphate were increased compared to the control, whereas those of pyrophosphate and metaphosphate were decreased. The volume expansion ratios of PG and polyphosphate were slightly increased. Turbidities of PG and polyphosphate were lower than those of the control, whereas those of pyrophosphate and metaphosphate were increased in cooked noodles. The bacterial counts of wet noodles made with PG, polyphosphate, metaphosphate and pyrophosphate were all lower than those of the control after storage at 5$^{\circ}C$.

• 약학회지
• /
• 제22권4호
• /
• pp.193-200
• /
• 1978

Cholic, ursodesoxycholic, chenodesoxycholic, desoxycholic and hydesoxycholic acids were dissolved in the propylene glycol to make solution and then above solution of cholanic acids on bile secretion was investigated by injection those solutions into small intestine of rabbits and albino rats. The cholates in bile juice from rabbits injected with cholic acid were remarkably increased and therefore it exhibited a typical choleretic action. In view of pharmacological point, desoxycholic acid is considered as superior hydrocholeretic agent, and ursodesoxycholic and chenodesoxycholic acids have similar effect in decreasing order. However, the effect of bile secretion by hyodesoxycholic acid was almost negligible as that by propylene glycol administered. The cholate content in the bile juice from albino rat was increased by cholic and desoxycholic acids in decreasing order: i.e., they exhibited choleretic action. In the case of ursodesoxycholic and chenodesoxycholic acids, the concentration of cholate was slightly increased in bile juice from the rat, so that these cholates showed a weak choleretic action. While total output of bilirubin was increased by chenodesoxycholic acid, the other cholanic acid showed no effect in the rabbit.

• 한국연초학회지
• /
• 제23권1호
• /
• pp.77-81
• /
• 2001

This study was conducted to determine menthol migration from the tobacco to the filter and the change in percentage of menthol in pack for different mentholated cigarettes. Methanol was used to extract menthol from tobacco, filter and foil. A known weight of internal standard was added to each extract and then the extracts were analyzed by gas chromatography. After 4 days, 95% of the menthol applied to the foil was delivered into the tobacco and filter, but in case of menthol applied to the tobacco, the percentage of menthol that migrated from the tobacco to the filter was below 10%. After 100 days, 30-45% of the menthol in the tobacco had migrated into the filter. The amount of menthol in the pack decreased after 20 days of storage, however, the remaining menthol in cigarette treated with 0.30% propylene glycol was higher in amount than that with 0.12% propylene glycol In analysis on menthol transfer to mainstream smoke, the most efficient sample was the cigarette with menthol applied to the foil rather than to the tobacco.

• Journal of Industrial and Engineering Chemistry
• /
• 제67권
• /
• pp.255-265
• /
• 2018

The huge amount of solvents used in the semi-conductor and display industry typically result in waste of valuable solvents which often form complex azeotropic mixtures. This study explored a recovery process of a quaternary waste solvent, comprising methyl 2-hydroxybutyrate, propylene glycol monomethyl ether acetate, ethyl lactate, and ethyl-3-ethoxy propionate. In this study, a novel shortcut column method with a graphical approach was exploited for the distillation column design of complex quaternary azeotropic mixtures. As a result, the proposed shortcut method and design procedure solved the complex separation paths successfully with less computational efforts while achieving all requirements for component purity.

• Journal of Pharmaceutical Investigation
• /
• 제32권2호
• /
• pp.107-112
• /
• 2002

To investigate the feasibility of developing a novel melatonin plaster, the effects of vehicles and drug loading dose on the in vitro permeation of melatonin across dorsal hairless mouse skin from pressure-sensitive adhesive (PSA) matrices were examined. Vehicles employed were propylene glycol laurate (PGL), propylene glycol monocaprylate (PGMC) and diethylene glycol monoethyl ether (DGME). Among PSAs used, only $Duro-Tak^{\circledR}$ 87-2196 showed a good peeling property. The release from $Duro-Tak^{circledR}$ 87-2196 was proportional to the square root of time, and dose-dependent. The fluxes increased as the loading dose increased over the doses under solubility. The relatively high permeation flux $(3.03{\pm}1.37\;{\mu}g/cm^2/hr)$ was obtained when using PGMC at the melatonin loading dose of $45\;mg/140\;cm^2$. Lag time was not affected by the vehicles used but by the thickness spread. The melatonin plasters prepared using PGMC showed a good adhesive property onto skin, and showed no crystal formation.