• Title/Summary/Keyword: Glycerin

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Effect of glycerin on the surface hardness of composites after curing (글리세린이 복합레진의 중합 후 표면경도에 미치는 영향)

  • Park, Hyun-Hee;Lee, In-Bog
    • Restorative Dentistry and Endodontics
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    • v.36 no.6
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    • pp.483-489
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    • 2011
  • Objectives: The purpose of this study was to examine the effect of glycerin topical application on the surface hardness of composite after curing. Materials and Methods: A composite (Z-250, 3M ESPE) was packed into a disc-shaped brass mold and light cured according to one of the following protocols. Group 1 (control) was exposed to air and light cured for 40 sec, group 2 was covered with a Mylar strip and light cured for 40 sec, group 3 was surface coated with glycerin and light cured for 40 sec, and group 4 was exposed to air and light cured for 20 sec and then surface coated with glycerin and cured for additional 20 sec. Twenty specimens were prepared for each group. The surface hardnesses of specimens were measured with or without polishing. Five days later, the surface hardness of each specimen was measured again. Data were analyzed by three-way ANOVA and Tukey's post hoc tests. Results: The surface hardnesses of the unpolished specimens immediately after curing decreased in the following order: group 2 > 3 > 4 > 1. For the polished specimens, there was no significant difference among the groups. Within the same group, the hardness measured after five days was increased compared to that immediately after curing, and the polished specimens showed greater hardness than did the unpolished specimens. Conclusions: The most effective way to increase the surface hardness of composite is polishing after curing. The uses of a Mylar strip or glycerin topical application before curing is recommended.

Influence of Wetting Agents on Physical Properties of Soft Contact Lens (친수성 소프트 콘택트렌즈의 물리적 특성에 미치는 습윤성 재료의 영향)

  • Lee, Min-Jae;Sung, A-Young;Kim, Tae-Hun
    • Journal of Korean Ophthalmic Optics Society
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    • v.19 no.1
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    • pp.43-49
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    • 2014
  • Purpose: The physical and optical characteristics of hydrophilic contact lens polymerized with addition of glycerin and PVP(polyvinylpyrrolidone) in the basic hydrogel contact lens material were evaluated. Methods: This study used glycerin and PVP(polyvinylpyrrolidone) with the cross-linker EGDMA (ethylene glycol dimethacrylate), HEMA (2-hydroxyethyl methacrylate) and the initiator AIBN (azobisisobutyronitrile) for copolymerization. Results: Measurements of the physical characteristics of the copolymerized material including PVP(polyvinylpyrrolidone) showed the refractive index of 1.4382~1.4288, tensile strength of 0.3446~2542 kgf and water content and contact angle of sample showed the increase of 13.49% and decrease of 21.44% independently. And also, the physical characteristics of the copolymerized material including glycerin showed the refractive index of 1.4330~1.4328, tensile strength of 0.2974~0.2854 kgf, water content 35.58~36.53% and contact angle of sample showed the decrease of 37.64%. Conclusions: Based on the results of this study, the produced copolymers is suitable for conventional lens with high wettability. Also, glycerin minimized the changes of water content and refractive index at the same time, increased the wettability of the hydrogel lens materials.

Solubilization and Fomulation as Soft Gelatine Capsule of Biphenyldimethyldicarboxylate (비페닐디메칠디카르복실레이트의 가용화 및 연질캅셀제로의 설계)

  • Park, Gee-Bae;Chung, Chae-Kyong;Lee, Kwang-Pyo
    • Journal of Pharmaceutical Investigation
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    • v.26 no.1
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    • pp.1-11
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    • 1996
  • Biphenyldimethyldicarboxylate (PMC), which has been used to treat hepatitis, is insoluble in water, therefore it has low bioavailability after oral administration. For the purpose of increasing the dissolution rate of PMC, the physical mixtures and inclusion complexes of PMC and $dimethyl-{\beta}-cyclodextrin\;(DM\;{\beta}CD)\;or\;hydroxypropyl-{\beta}-cyclodextrin\;(HP{\beta}CD)$ in molar ratio of 1 : 1 and 1 : 2 were prepared by solvent evaporation method. Mixed micelles of PMC were prepared by reacting PMC with bile salts [sodium cholate(NaC), sodium glycocholate (NaGC)] and oleic acid (OA) or palmitoylcarnitine chloride(PCC). Chloroform/water partition coefficient (PC) of PMC was 36.14 in artificial gastric juice (AGJ) and 33.47 in artificial intestinal juice (AIJ), respectively, on the other hand octanol/water PC was 63.36. PMC formulation was prepared by reacting PMC with PEG400-glycerin system(95 : 5, 90 : 10, respectively) and PEG400-PEG4000-glycerin system (70 : 25 : 5, 65 : 25 : 10, respectively). Dissolution test was performed in AGJ and AIJ by paddle method at $37{\pm}0.5^{\circ}C$. The dissolution rates of PMC tablets on the market were 5.74% and 8.26% at AGJ and AIJ, respectively and marketed PMC capsules were 22.14% and 28.64% at AGJ and AIJ, respectively. The dissolution rates of inclusion complexes of PMC with $DM{\beta}CD$ and $HP{\beta}CD$ in a molar ratio of 1 : 1 were more fast than those of corresponding physical mixtures. The decreasing order of dissolution rates was as follows; PMC-PEG400-PEG4000-glycerin formulation > PMC-PEG400-glycerin formulation > mixed micelles > CD inclusion complexes. The dissolution rates of PMC-PEG400-glycerin and PMC-PEG400-PEG4000-glycerin formulation were most fast and the percentage of dissolution was almost 100% within 20 minutes. And their dissolution rates after 120 minutes were markedly increased as compared with capsules on the market (4.0-fold and 3.2-fold in PMC-PEG400-glycerin formulation at AGJ and AIJ, respectively, and 4.8-fold and 3.7-fold in PMC-PEG400-PEG4000-glycerin formulation at AGJ and AIJ, respectively).

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Failure of Urination and Defecation after Intrathecal Phenol-glycerin Block for Management of Chronic Perineal Pain -A case report- (만성회음부 통증 치료를 위한 지주막하 페놀글리세린 차단 후 발생한 배변 및 배뇨장애 -증례 보고-)

  • Ahn, Hyun-Jung;Kim, Jong-Il;Lee, Sang-Gon;Ban, Jong-Seouk;Min, Byung-Woo
    • The Korean Journal of Pain
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    • v.12 no.2
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    • pp.268-271
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    • 1999
  • Intrathecal phenol-glycerin block is a potent tool in stepwise approach to intractable perineal pain. At outpatient clinic, intrathecal phenol-glycerin block have been frequently used to control the cancer pain, as this procedure does not require special equipment. However, undesirable effects may occur with any given intrathecal injection. Although most side effects do not last long, they deserve well to prevent. Recently, we have been controlled the perineal and perianal cancer pain with intrathecal phenol-glycerin block without any specific complications. However, one patient we managed experienced that one patient, with this procedure for chronic non-malignant perineal pain control experience gait disturbance and one-week of voiding and defication difficulties. This research reports these practices, including the review of literature.

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Synthesis and Fluorescence Behavior of Vinyl Polymers with Substituted Naphthalimide Group(I) (치환된 나프탈이미드기를 가지는 비닐고분자의 합성과 형광특성(I))

  • DaeHeeOh
    • Journal of the Korean Graphic Arts Communication Society
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    • v.15 no.2
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    • pp.77-90
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    • 1997
  • Positive type presensitized offset plate developer were blended by quantitative analysis method. The test had been proceeeded to check variation of developability, shelf life and tone reproduction by SiO2/Na2O ratio to PS plate developer, added glycerin, and sodium phosphate with glycerin. This study of tone reproduction had been tested 5 times to get accuracy by PS platesusing kodak CCG C-3, KMS. The test result of tone reproduction of presensitized offset plates can be summarized as follows ; major compositions in positive type plate developer were Na, Si, K and P, developability were increased by Sio2/NaO2 ratio in positive type plate developer. Shelf life can be kept by add glycerin to positive type plate developer. Tone reproduction were improved by sodium phosphate due to buffer action while shelf life can be kept by add glycerin in positive type plate developer.

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The physicochemical properties of rice extrudate by addition of emulsifier(Glycerin fatty acid ester)

  • 고광진
    • Journal of the East Asian Society of Dietary Life
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    • v.2 no.2
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    • pp.277-282
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    • 1992
  • This study was designedto investigate changes in phsicochemical properties of rice extrudate with added glycerin fatty acid ester extruded by single screw extruder. According to emulsifier content, expansion ratio and water solubility index were represented minimum in rice extrudate with added 2.0% and 2.5% glycerin fatty acid ester. Extrudate with added 1.5% emulsifier revealed lowest break strength and bulk density, so got a tender and light texture. Meanwhile water absorption index was showed maximum at 1.5% emulsifier content. As emulsifier content increased, lightness raised. By the microstructure obsorved with image analyzer, addition of emulsifier had decreased area and fractarea of air cells of cross section of extrudates. On the results of this research, quality of extrudate with added 1.5% glycerin fatty acid ester was considered very well than 100% rice extrudate, because of tender and light texture, highest water absorption indexand fine structure with higher lightness.

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Biodiesel Refining and Glycerin Recovering Process of Transesterification from Tra Catfish Fat

  • Huong, Le Thi Thanh;Tan, Phan Minh;Hoa, Tran Thi Viet;Lee, Soo
    • Journal of the Korean Applied Science and Technology
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    • v.26 no.1
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    • pp.1-9
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    • 2009
  • Nowadays, Tra catfish fat is given attention as an appropriate material for biodiesel production in Vietnam. The aim of this work is to investigate the optimal conditions of refining biodiesel and recovering glycerin by the transesterification from Tra catfish fat using KOH catalyst. As our results, the yield of transesterification was achieved to 94.17% at $50^{\circ}C$ for 45 min with 6:1 molar ratio of methanol to fat in the presence of 0.8% KOH catalyst, and wherein the biodiesel was refined by washing with distilled water at $70^{\circ}C$ and dried in a microwave oven. The yield of raw glycerin recoveries from the transesterification process was 78.58%. The purity of raw glycerin was 84.14% by the conditions of neutralization state with $H_{3}PO_{4}$ solution (pH = 5), $70^{\circ}C$, and 60 min. Activated carbon (3.0 wt.%) was used for the bleaching process at $80^{\circ}C$ for 20 min. The biodiesel was obtained in accordance with for ASTM D 6751 (biodiesel standard). The ash and water of raw glycerins were 7.32 and 8.01%, respectively, and implied that the raw glycerin is very promising candidate to be used as a raw material for textile and cosmetic industries.

Effect of Emulsion State on the Physical Properties of Carthamus Red Pigment (유화조건이 홍화적색소의 물성에 미치는 영향)

  • Lee, Seung-Ryong;Chang, Kyu-Seob;Lee, Suk-Kun;Yoon, Hye-Hyun;Hahn, Tae-Ryong
    • Korean Journal of Agricultural Science
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    • v.27 no.1
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    • pp.54-62
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    • 2000
  • This study was performed to evaluate the food technological properties according to different emulsion state of carthamus red pigment. For making emulsion, lecithin was used as an emulsifier and polyglycerol monooleate(PGMO) and polyoxyethylene sorbitan monooleate(Tween 80) were used as an assistant, and glycerin, distilled water and soybean oil were used as base materials respectively. Paprika stock solution was used for comparing carthamin on the rheological properties. The results were described as following: 1. Hunter L-value was not drastically increased until passed by 8 hours for glycerin, carthamin, and lecithin mixed sample. 2. Hunter a-value was higher at carthamin added sample than others. and b-value was higher to paprika added sample than others. 3. The viscosity, shear rate and shear stress levels in which glycerin was used as base material were higher than soybean oil or distilled water. 4. In which soybean oil was used as base material. lecithin was not affected on the rheological properties. But, in which glycerin was used. the lecithin was higher affected on carthamin than paprika. 5. The value of shear stress was increased both carthamin and soybean oil. However, that of shear rate was shown similar trends.

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Superconducting Properties of Mg(B1-xCx)2 Bulk Synthesized Using Magnesium and Glycerin-treated Boron Powder (마그네슘과 글리세린 처리한 붕소 분말로 합성한 Mg(B1-xCx)2의 초전도 특성)

  • Kim, Yi-Jeong;Jun, Byung-Hyuk;Park, Soon-Dong;Tan, Kai Sin;Kim, Bong-Goo;Sohn, Jae-Min;Kim, Chan-Joong
    • Journal of Powder Materials
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    • v.15 no.3
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    • pp.182-187
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    • 2008
  • Carbon was known to be one of effective additives which can improve the flux pinning of $MgB_2$ at high magnetic fields. In this study, glycerin $(C_3H_8O_3)$ was selected as a chemical carbon source for the improvement of critical current density of $MgB_2$. In order to replace some of boron atoms by carbon atoms, the boron powder was heat-treated with liquid glycerin. The glycerin-treated boron powder was mixed with an appropriate amount of magnesium powder to $MgB_2$ composition and the powder pallets were heat treated at $650^{\circ}C\;and\;900^{\circ}C$ for 30 min in a flowing argon gas. It was found that the superconducting transition temperature $(T_c)$ of $Mg(B_{1-x}C_x)_2$ prepared using glycerin-treated boron powder was 36.6 K, which is slightly smaller than $T_c$(37.1 K) of undoped $MgB_2$. The critical current density $(J_c)$ of $Mg(B_{1-x}C_x)_2$ was higher than that of undoped $MgB_2$ and the $T_c$ improvement effect was more remarkable at higher magnetic fields. The $T_c$, decrease and $J_c$ increase associated with the glycerin treatment for boron powder was explained in terms of the carbon substitution to boron site.

The Clinical Study on 45 Cases of Patients of constipation caused by C.V.A. who were treated with Bo-Riu Enema(保留灌腸) (배대승기탕(倍大承氣湯) 보류관장(保留灌腸)을 시행(施行)한 중풍변폐(中風便閉) 환자(患者) 45례(例)에 대(對)한 임상적(臨床的) 고찰(考察))

  • Kang, Young-Lok;Kim, Youn-Jin;Hwang, Chi-Won
    • The Journal of Internal Korean Medicine
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    • v.21 no.2
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    • pp.329-336
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    • 2000
  • During 9 months the clinical study on the 45 cases constipation patients caused by C.V.A, who were treated with Bo-Riu Enema, was done in the Department of Oriental Internal Medicine II, Oriental Medicine Hospital, Taejon University. The result of this study is compared with glycerin-enema treated group. The results were as follows ; 1. The incidence rate of constipation caused by C.V.A is higher in old aged group. 2. The incidence rate of constipation caused by C.V.A is higher in Tae-Um-In(太陰人). 3. The improvement rate of constipation caused by C.V.A is higher in Bo-Riu Enema treated group than in glycerin-enema. 4. The admission period is shorter in Bo-Riu Enema treated group than in glycerin-enema. 5. In case of paralytic ileus, the improvement rate of constipation caused by C.V.A is higher in Bo-Riu Enema treated group than in glycerin-enema.

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