• Title/Summary/Keyword: glycerin

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Selection and Cultivation of Microorganism Producing Iron Superoxide Dismutase(Fe-SOD) (Iron Superoxide Dismutase( Fe-SOD)를 생산하는 미생물의 선발 및 배양)

  • 이태호;정숙현
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.23 no.6
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    • pp.1020-1026
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    • 1994
  • Pseudomonas plycolor was used to investigated the optimal culture condition to examine the various properties of superoxide dismutase (SOD). this SOD was inhibited by $H_2O_2$, azide ion, but not by cyanide ion. This result indicates that the enzyme might be a Fe-SOD. The composition of optimal culture medium for the enzyme production was 3% of glycerin, 1% of polypeptone, 0.5% of meat extract, 0.2% of KCI and the initial ph was 9.0 . The cultivation for the enzyme production was carried out in 500ml shaking flask containing 100ml of the optimal medium at $30^{\circ}C$ on a reciprocal shaker. The enzyme production reached maximum at 15hrs of cultivation and then declined sharply afterward.

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Measurements of Flow Meniscus Movement in a Micro Capillary Tube (마이크로 원형 모세관에서 계면 이동 현상의 측정)

  • Lee, Sukjong;Sung, Jaeyong;Lee, Myeong Ho
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.22 no.1
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    • pp.15-21
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    • 2013
  • In this paper, a high-speed imaging and an image processing technique have been applied to detect the position of a meniscus as a function of time in the micro capillary flows. Two fluids with low and high viscosities, ethylene glycol and glycerin, were dropped into the entrance well of a circular capillary tube. The filling times of the meniscus in both cases of ethylene glycol and glycerin were compared with the theoretical models - Washburn model and its modified model based on Newman's dynamic contact angle equation. To evaluate the model coefficients of Newman's dynamic contact angle, time-varying contact angles under the capillary flows were measured using an image processing technique. By considering the dynamic contact angle, the estimated filling time from the modified Washburn model agrees well with the experimental data. Especially, for the lower-viscosity fluid, the consideration of dynamic contact angle is more significant than for the higher-viscosity fluid.

Release Characteristics to Vitamin $B_{2}$ of Chitosan Ointments In vitro (In vitro에서 키토산 연고의 비타민 $B_{2}$ 방출 특성)

  • Oh, Se-Young;Hwang, Sung-Kwy;Hwang, Yong-Hyun
    • Journal of the Korean Applied Science and Technology
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    • v.17 no.1
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    • pp.43-48
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    • 2000
  • Drug delivery system(DDS) applied to various fields, such as medicine, cosmetics, agriculture and necessities of life. Among these application fields, DDS is often used as the method of drug dosage into the epidermic skin. We investigated characters of transdermal therapeutic system(TTS) and the skin permeability of that with applying DDS. Chitosan was selected as material of TTS. We investigated the permeation of chitosan ointment containing drug in rat skin using horizontal membrane cell model. Permeation properties of materials were investigated for water-soluble drug such as riboflavin in vitro. We used glycerin, PEG 600 and oleic acid as enhancers. Since dermis has more content water(hydration) than the stratum corneum, skin permeation rate at steady state was highly influenced when glycerin was used in water-soluble drug. The permeation rate of content enhancer and drug was found to be faster than that of content water-soluble drug only. These results showed that skin permeation rate of drug across the composite was manly dependent on the property of ointment base and drug. Proper selection of the polymeric materials which resemble and enhance properties of the delivering drug was found to be important in controlling the skin permeation rate.

CONTROL OF LASER WELD KEYHOLE DYNAMICS BY POWER MODULATION

  • Cho, Min-Hyun;Dave Farson
    • Proceedings of the KWS Conference
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    • 2002.10a
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    • pp.600-605
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    • 2002
  • The keyhole formed by high energy density laser-material interaction periodically collapses due to surface tension of the molten metal in partial penetration welds. The collapse sometimes traps a void at the bottom of the keyhole, and it remains as welding defects. This phenomenon is seen as one cause of the instability of the keyhole during laser beam welding. Thus, it seems likely that improving the stability of the keyhole can reduce voids and uniform the penetration depth. The goal of this work is to develop techniques for controlling laser weld keyhole dynamics to reduce weld defects such as voids and inconsistent penetration. Statistical analysis of the penetration depth signals in glycerin determined that keyhole dynamics are chaotic. The chaotic nature of keyhole fluctuations and the ability of laser power modulation to control them have been demonstrated by high-speed video images of laser welds in glycerin. Additionally, an incident leading beam angle is applied to enhance the stability of the keyhole. The quasi-sinusoidal laser beam power of 400Hz frequency and 15$^{\circ}$ incident leading beam angle were determined to be the optimum parameters for the reduction of voids. Finally, chaos analyses of uncontrolled signals and controlled signals were done to show the effectiveness of modulation on the keyhole dynamics. Three-dimensional phase plots for uncontrolled system and controlled system are produced to demonstrate that the chaotic keyhole dynamics is converted to regular periodic behavior by control methods: power modulation and incident leading beam angle.

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Effect of Burn out Print Finishing on Cellulose Fiber Damage (섬유소계 직물의 탄화날염가공이 섬유손성에 미치는 영향)

  • 신정숙;송석규
    • Journal of the Korean Society of Clothing and Textiles
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    • v.25 no.1
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    • pp.124-131
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    • 2001
  • To find out the effect of burn out print finishing for better quality of fabric, examined processing which could make less damages on the fiber because the biggest problem is remained fibers damage after burn out print finishing. Fiber damage examined to the condition of finishing material NaHSO$_4$and H$_2$SO$_4$, 3~10min., 100~13$0^{\circ}C$, glycerin. The fiber damages evaluated the break strength and the surface condition by SEM. Among satin, pile fabric which remained fiber is silk, warp knitted fabric which remained fiber is polyester, the fibers damage level were warp knitted fabric$0^{\circ}C$, glycerin and for 6 minutes by NaHSO$_4$. When carbonized by 20%. 50% and 70% to express textile design, carbonizing rate was not effect on the fiber damage very much. There was almost no damages with glycerine, and almost no damages during 3~6minutes fixation time, 10$0^{\circ}C$ steaming heat fixation by NaHSO$_4$and H$_2$SO$_4$. Without glycerine, there were damage by hydrolysis on polyesters surface and the fiver was broken by fixation time.

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Experimental studies on the axisymmetric sphere-wall interaction in Newtonian and non-Newtonian fluids

  • Lee, Sang-Wang;Sohn, Sun-Mo;Ryu, Seung-Hee;Kim, Chongyoup;Song, Ki-Won
    • Korea-Australia Rheology Journal
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    • v.13 no.3
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    • pp.141-148
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    • 2001
  • In this research, experimental studies leave been performed on the hydrodynamic interaction between a spherical particle and a plane wall by measuring the force between the particle and wall. To approach the system as a resistance problem, a servo-driving system was set-up by assembling a microstepping motor, a ball screw and a linear motion guide for the particle motion. Glycerin and dilute solution of polyacrylamide in glycerin were used as Newtonian and non-Newtonian fluids, respectively. The polymer solution behaves like a Boger fluid when the concentration is 1,000 ppm or less. The experimental results were compared with the asymptotic solution of Stokes equation. The result shows that fluid inertia plays all important role in the particle-wall interaction in Newtonian fluid. This implies that the motion of two particles in suspension is not reversible even in Newtonian fluid. In non-Newtonian fluid, normal stress difference and viscoelasticity play important roles as expected. In the dilute solution weak shear thinning and the migration of polymer molecules in the inhomogeneous flow field also affect the physic of the problem.

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Centrifuge Modeling of Soft Clay with Vertical Drains Considering the Centrifuge Similarity (상사성을 고려한 배수재 설치 연약점토 지반의 원심모델링)

  • Yoo, Nam-Jae;Hong, Young-Kil;Jeong, Gil-Soo;Cho, Han-Ki
    • Journal of Industrial Technology
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    • v.27 no.A
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    • pp.111-120
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    • 2007
  • This paper is results of experimental research on the effect of application of similarity related to permeability of soil on the consolidation behavior as centrifuge modeling of consolidation is performed with the centrifuge model facility. In this research, the permeability of soil was controlled by changing the viscosity of porewater as the mixed water with glycerin was used during the centrifuge model experiments. The effect of drainage path on consolidation was investigated by installing the vertical drains. A serise of centrifuge model tests with conditions of single vertical and radial horizontal drainage were carried out. Kaolinite and Jumunjin standard sand were used as soft clay and surcharges respectively during tests. For testing condition of single vertical drainage considering similarity of permeability, it was found that consolidation with mixed porewater with glycerin was delayed in comparisons sons with test results with water only. For conditions of horizontal drainage with vertical drains, a low permeability by changing the viscosity of pore water resulted in delayed degree of consolidation at an initial stage of consolidation. But, it predicted not much differences in settlement as long as the consolidation time was sufficiently long enough to finish consolidation. Consequently, it was found that similarity in permeability should be considered to be critical for the case of centrifuge model experiments related to consolidation with long drainage path.

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Preparation of high-performance nanofiltration membrane with antioxidant properties

  • Yu, Feiyue;Zhang, Qinglei;Pei, Zhiqiang;Li, Xi;Yang, Xuexuan;Lu, Yanbin
    • Membrane and Water Treatment
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    • v.13 no.4
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    • pp.191-199
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    • 2022
  • In industrial production, the development of traditional polyamide nanofiltration (NF) membrane was limited due to its poor oxidation resistance, complex preparation process and high cost. In this study, a composite NF membrane with high flux, high separation performance, high oxidation resistance and simple process preparation was prepared by the method of dilute solution dip coating. And the sulfonated polysulfone was used for dip coating. The results indicated that the concentration of glycerin, the pore size of the based membrane, the composition of the coating solution, and the post-treatment process had important effects on the structure and performance of the composite NF membrane. The composite NF membrane prepared without glycerol protecting based membrane had a low flux, when the concentration of glycerin increased from 5% to 15%, the pure water flux of the composite NF membrane increased from 46.4 LMH to 108.2 LMH, and the salt rejection rate did not change much. By optimizing the coating system, the rejection rate of Na2SO4 and PEG1000 was higher than 90%, the pure water flux was higher than 40 LMH (60psi), and it can withstand 20,000 ppm.h NaClO solution cleaning. When the post treatment processes was adjusted, the salt rejection rate of NaCl solution (250 ppm) reached 45.5%, and the flux reached 62.2 LMH.

Identification of larval Gnathostomn obtained from imported Chinese loaches (중국산 수입 미꾸리로부터 획득한 악구충 제3기 유충의 종 동정)

  • 손운목;이순형
    • Parasites, Hosts and Diseases
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    • v.34 no.3
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    • pp.161-168
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    • 1996
  • We observed the morphological characteristics and identified the species of gnathostome larvae obtained from the imported Chinese loaches. The early third-stage larvae ($EL_3$) were collected from viscera of the loaches and a part of them were infected to mice. The advanced third-stage larvae ($AdL_3$) were recovered from the mice at 4 weeks post-infection. both larval worms were fixed loth 10% formalin, cleared in alcohol-glycerin solution, mounted with glycerin-jelly, and observed. A total of 369 $EL_3$ were collected from viscera of 9,493 Chinese loaches. The whole body of $EL_3$ was covered with about 190 transverse rows of minute cuticular spines and $0.624{\;}{\times}{\;}0.101{\;}mm$ in average size. A pair of lips were protruded at the anterior end, and the muscular esophagus and brownish intestine were followed. The characteristic head bulb was provided with 4 rows of hooklets. The average number of hooklets in the respective row was 36.7, 39.5, 41.6 and 44.3 posteriorly $AdL_3$ was $2.660{\;}{\times}{\;}0.346{\;}mm$ in average size, and retained the esophagus (about 0.755 mm length) and cervical sac (about 0.355 mm length). The average number of hooklets in the respective row on the head bulb was 39.0, 41.9, 43.9 and 45.6, posteriorly. On the basis of the morphological characteristics, they were identified as the third-stage larvae of Gnathostomc hispinun.

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Effect of Culture Condition on Hanwoo Embryonic Developments and Their Sunrival after Vitrification (배양 조건에 따른 한우 수정란의 발달과 초자화 동결 후 수정란의 생존성 비교)

  • Cho, Sang-Rae;Choi, Sun-Ho;Choe, Chang-Yong;Son, Jun-Kyu;Lee, Poong-Yeon;Ko, Yeoung-Kyu;Kim, Hyun-Jong;Yeon, Sung-Heum;Son, Dong-Soo
    • Journal of Embryo Transfer
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    • v.25 no.3
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    • pp.189-193
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    • 2010
  • We investigated the cleavage rate and blastocyst yield for each culture condition to enhance tolerance of cryo-preservation of bovine IVF embryo with relatively lower cryo-tolerance compared to in vivo embryo. The cleavage rate and blastocysts yield for CR1aa, IVMD, IVD, CR1aa+10% FBS were 73.2, 69.3, 72.8, 68.5% and 44.1, 30.8, 33.3, 48.0%, respectively. The values did not differ among each treatments without serum. For embryo vitrification, In vivo and In vitro blastocysts were exposed to VS1(10% glycerin, 0.1 M glucose, 0.1 M sucrose, PEG 1%) for 5 min, and VS2 (10% glycerin, 10% EG, 0.2 M glucose, 0.2 M sucrose, PEG 2%) for 5 min and then VS3 (10% glycerin, 30% EG, 0.3 M glucose, 0.3 M sucrose, PEG 3%) for 1 min. The exposed embryos were then loaded into the 0.25 ml plastic straws and then plunged into liquid nitrogen. The straws were held for period of 1 to 2 weeks before thawing. In embryo viability, no differences in blastocyst re-expansion rates were found between in vivo and in vitro embryos. whereas expansion-BL rates was significantly higher for in vivo-derived embryos (72.7%) when compared to in vitro-derived embryos (51.4%), respectively (P<0.05). In conclusion, our results indicate that combined use of CRIaa culture medium with vitrification might enhance tolerance of cryopreservation for bovine IVF embryo production.