• Title/Summary/Keyword: soaking

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Controlled Release of Progesterone from Polyethylene Oxide-Silicone Rubber Matrix

  • Kim, Sung-Ho;O, Sung-l
    • Archives of Pharmacal Research
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    • v.12 no.3
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    • pp.191-195
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    • 1989
  • The release of progesterone from monolithic devices composed of different ratios of polyethylene oxide (PEO; mw 20, 000) and hydrophobic polydimethylsiloxane was investigated. Water soluble PEO soaked into the polymer provided controlled release of progesterone. The release rate of progesterone could be controlled by varying the contents of PEO and progesterone in soaking solution. The progesterone release rate from silicone devices increased as the content of PEO in devices increased, while it decreased as the content of PEO in soaking solution increased. The release rate may be made by simple alterations of geometry of devices controlled swelling and the change in the physical structure of polymer network. Hydrophobic polydimethylsiloxane containing PEO and progesterone can provide a contraceptive material for prolonged release of progesterone.

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Effects of Phytohormone on the Root Formation of Stem Cuttings in Panax ginseng C.A. Meyer (묘삼경의 근형성에 미치는 식물 생장 조절물질의 영향)

  • 최광태;양덕춘;양덕조
    • Journal of Ginseng Research
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    • v.9 no.1
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    • pp.42-53
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    • 1985
  • This study was carried out to obtain the basic information about the large scale propagation of ginseng (Panax ginseng C.A. Meyer). Therefore, the stem cuttings of 1-year old ginseng, treated with various concentrations of plant growth regulators for 5 seconds (quick dipping) and 24 hours (prolonged soaking), were cultured. The root formation of stem cuttings was varied with the concentrations, kinds, and treatment methods of plant growth regulators. Besides normal-looking roots various malformed roots were observed. In the prolonged soaking method, the culture of stem cuttings, treated with 10 ppm of IBA or NAA, resulted in profuse root regeneration. And stem cuttings, in quick dipping method, treated with 2000 ppm of IBA or NAA resulted in more excellent root regeneration. In general, IBA was more vigorous for the root formation than NAA, The treatment with 50 ppm kinetin or 100 ppm BA brought good result for the retardation of senescence of stem cuttings and BA treatment was more effective than kinetin. As for the saponin content of roots derived from stem cutting culture, the roots, formed by non-treatment of growth regulators, were higher in saponin content than those formed by treatment of growth regulators.

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Strength Evaluation of Adhesive Bonded Joint for Light Weight Structure by Single-Lab Joint Test (단면 겹치기 이음 시험에 의한 경량구조물용 접착 이음강도의 평가)

  • 이강용;김준범;최홍섭;우형표
    • Transactions of the Korean Society of Automotive Engineers
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    • v.5 no.2
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    • pp.87-93
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    • 1997
  • The bonding strength evaluation of light weight materials for electrical vehicle applications has been performed through single lap joint tests in which the design parameters such as fillet, joint style, adherend, bonding overlap length,bonding thickness, and environmental condition(soaking time in $25^{\circ}C$ water) are considered. It is experimentally oberved that lap shear strength of joint increases for higher fillet height, longer overlap length, and thinner bonding layer thickness. Al-Al adherend combination shows much higher lap shear strength than AL-FRP and FRP-FRP adherend combinations. Riveting at adhesive bonded joint of AL-AL adherend combination makes lap shear strength decrease. Effect of soaking time on lap shear strength is negligible.

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A Study on Microstructure and Phase Transformation of Sintered Body in $CaO-ZrO_2$ System ($CaO-ZrO_2$계 소결체의 상변화와 미구조에 관한 연구)

  • 박금철;최영섭
    • Journal of the Korean Ceramic Society
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    • v.20 no.3
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    • pp.217-226
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    • 1983
  • Adquate amount of calcia was added to the regent-grade Zirconia body. Here the amount and the form of calcia were 7-21 mol% and regent-grade calcium cabonate respectively. The specimens were fired at 175$0^{\circ}C$ for 0, 3, 5 and 7 hours respectively. The phase Strength X-ray diffraction analysis and Scaning electron microscopy. The results were as follows (1) As the additive amount of calcia was increased the firing linear shrinkage apparent density compressive strength and modulus of rupture decreased but the apparent porosity increased. (2) The specimens soaked and containing calcia displayed the grain growth. (3) Monoclinic and cubic zirconia were seen in the sepcimens containing 7 mol% calcia. When without soaking the specimens containing 7-10 mol% calcia had the volume change by monoclinic$\rightleftharpoons$tetragonal transformation. (4) The lattice parameter increased according as the calcia additive was increased. The specimens containing above 19mol% calcia had the costant lattice parameter. The value of that was from 5.1264 to 5.1396 $\AA$ in the case of 7 hours soaking.

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Pore Modification of Sol-Gel Driven Alumina Membrane via Soaking and Vapor-Deposition Method

  • 이상연;이승진;양승만;박승빈
    • Proceedings of the Membrane Society of Korea Conference
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    • 1995.04a
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    • pp.58-59
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    • 1995
  • 기체 분리용 무기분리막은 고분자막과 비교하여 열 및 구조적 안정성이 우수하므로, 석탄가스화반응 혼합기체중의 기체분리 등 고온 또는 고압공정에 적합한 분리방법으로서 주목되고 있다. 기체의 분리를 위한 무기재료막은 크게 다공성막과 비다공성막으로 나눌 수 있으며, 이 중 비기공 성막의 경우 높은 선택도를 가지나 투과도가 낮아 경제성이 떨어지는 것으로 평가되고 있다. 한편, 기존의 다공성막의 경우 투과도는 높으나 기체의 분리가 혼합기체중 각 기체의 분자량의 차이에 의존하는 Knudsen 확산에 제한되는 낮은 선택도를 갖는 단점이 있다. 따라서 다공성막의 기공을 특정기체의 선택도가 우수한 촉매물질등으로 개선하여 비기공성막에 비해 우수한 투과도를 갖고, 기공성막에 비해 향상된 선택도를 보이는 복합막의 연구가 활발히 추진되고 이\ulcorner. 본 연구는 솔젤법에 의해 제조된 팔라듐 함침 알루미나 지지막의 기공을 침투$\cdot$증착(Soaking and Vapor-deposition)법에 의해 개선하여 기체의 투과도를 높게 유지하면서 수소의 선택성을 향상시키는 것을 목적으로 하였다.

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A study on medicinal theory of Wang-Ang(汪昻) (왕앙(汪昻)의 약물이론(藥物理論)에 관한 연구(硏究) (-수치이론(修治理論)에 관(關)하여-))

  • Byun Sung-Hui;Seo Bu-il
    • Herbal Formula Science
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    • v.7 no.1
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    • pp.77-87
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    • 1999
  • We studied medicinal theory on processing drugs of Wang-Ang. Wang-Ang used various methods of medicinal processing. He used such as soaking(浸), maceration(泡), washing(洗), elutriation(淘), mixing together(拌), refining powder with water(水飛) and floating(水漂) in medicinal processing with water. He used such as making hot(?), roasting in ashes(?), stir-frying with liquid(炙), parching(炒), heating(燒), baking(焙), stirring-baking(?) and distilling(煉) in medicinal processing with fire. He used such as steaming(蒸), boiling(煮), making hot and soaking(??) in medicinal processing with water and fire. And He used such as cooking(熟), making drugs into gelatin(制膠), making drugs into frostlike powder(制霜法), making drugs into bead(制珠), fermentation(生衣) and compound medicinal processing(複制法).

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Effect of Aqueous Solutions of Pesticides on Survival of Entomopathogenic Nematodes (농약이 곤충병원성 선충의 생존에 미치는 영향)

  • 이동운;추호렬;최은정
    • Asian Journal of Turfgrass Science
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    • v.13 no.4
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    • pp.213-222
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    • 1999
  • The toxic effects of four pesticides on the entomopathogenic nematodes. Heterorhabditis bacteriophora NC strain, Steinernema glaseri NC and Dongrae strain were tested by checking the mortality of infective juveniles(Ijs) in aqueous solution of pesticide. Mortality of Ijs was influenced by pesticide and concentration and soaking time. The herbicide alachlor and insecticide fenitrothion were toxic to Ijc of three entomopathogenic nematodes. But, the fungicides mepronil and tolclofos-methyl were nontoxic to Ijs. Tolclofos-methyl showed significantly very week toxicity at 28 days after soaking for S. glaseri NC strain. H. bacteriophora NC strain was more highly sensitive to high temperature condition then were the other nematodes.

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Cubic $ZrO_2$ Single Crystals Growth by Skull Method : Effect of Melt Homogenization in Crystallization (스컬(Skull)법에 의한 큐빅 $ZrO_2$단결정 성장 : 융액의 균질화가 결정성장에 미치는 영향)

  • 정대식;오근호
    • Journal of the Korean Ceramic Society
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    • v.27 no.5
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    • pp.597-604
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    • 1990
  • In Cubic ZrO2 crystal growth by Skull method, it was examined on effect of homonization on melt as keeping ZrO2(90mol%)-Y2O3(10mol%) melt with 1hr, 2hr, 4hrs, 8hrs, 16hrs, respectively. The optimum homonizing condition in this system was obtained by the examination between quality of grown crystals and soaking time of melt. It was obtained that the lower quality crystal could be produced in the longer holding melt than the optimum soaking time of melt in spite of the supposedly well homonized state, because the melt stability is sensibly dependent on the convective state of melt in skull method (cold crucible process).

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A Study on the Reduction of Inorganic Arsenic in Hijiki and Rice Using the Various Pretreatments and Inductively Coupled Plasma Mass Spectrometry

  • Nam, Sang-Ho;Lee, Dong-Chan
    • Mass Spectrometry Letters
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    • v.12 no.3
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    • pp.106-111
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    • 2021
  • Several pretreatment methods have been developed to reduce the inorganic arsenic, which is known to be highly harmful to humans, among various arsenic species present in hijiki and rice. The pretreatment methods were selected and developed as methods that can be non-harmful even after treatment and easily applied. Hijiki was applied by two methods. One was soaking in water at room temperature for various durations and the other was boiling of it in water for a short period of time. Rice was soaked in water with different rice-to-water ratios for various durations. The most effective method that reduced the inorganic arsenic in hijiki was to repeat parboiling for 5 minutes twice, which led to 79% reduction of the inorganic arsenic in it. In the case of rice, soaking for 24 hours at the ratio of 1:5 (rice:water) resulted in 51% reduction of inorganic arsenic in rice.