• 제목/요약/키워드: chloride media

검색결과 142건 처리시간 0.028초

스트렙토마이신 생성균주들과 배지들에 대한 비교연구 (Comparative Studies on Streptomycin Producing Strains and Media)

  • 김공환;조영애최석례구양모
    • KSBB Journal
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    • 제4권2호
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    • pp.162-166
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    • 1989
  • 스트렘토마이신 생산균주들인 Streptomyces griseus와 S.galbus strain들은 tryptic soy (TS) broth에 배양하여 항생제 생산을 조사하였을 때 S. griseus ATCC 27001이 가장 좋은 균주로 나타났다. 또한 S. griseus ATCC 12475와 ATCC 23345에서도 생장과 항생물질의 생산이 뛰어난 것으로 나타났다. 문헌에 보고된 streptomycin 생산배지들을 조사하여 본 결과 glucose-soybwan meal-sodium chloride (GSS) broth와 K (Chucken) broth에서, 조사한 다른 배지들에 비해 더 많은 양의 스트렙토마이신이 생성되었다. 이들 배지에 든 성분 중에 콩속에 든 특정한 성분이 스트렙토마이신의 생성을 활성화 시켰다. Meat extract를 soybean meal과 함께 가하여 주면 항생제 생성이 더 증가되었다. distillers' solubles도 meat extract와 유사한 활성이 관찰되나 com steep liquor를 가하여 주면 항생제 생산이 감소되었다.

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Numerical simulation of three-dimensional crack features and chloride ion transport in unsaturated and damaged mortar

  • Zhiyong Liu;Yunsheng Zhang;Jinyang Jiang;Rusheng Qian;Tongning Cao;Yuncheng Wang;Guowen Sun
    • Computers and Concrete
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    • 제31권6호
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    • pp.485-499
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    • 2023
  • Both damage and unsaturated conditions accelerate the transport of erosive media inside concrete. However, their combined effects have not been fully investigated. A multiscale mortar model using representative volume elements is developed, capturing the number and distribution in each phase. Afterwards, mortar damage microstructure evolution is simulated in the tensile process. Finally, the unsaturated mortar transport is predicted and analysed. The results indicate that damage significantly affects the diffusion process in the early stage, while the transport performance is weakened due to the obstruction of the nontransport phase in the later stage. The higher the saturation and the more connected pores, the faster the diffusion rate of chloride ions. Chloride ions spread around the cracks in a tree-like manner along. The model can very well predict the chloride ion transport performance of unsaturated and damaged mortar.

Effect of Cu Addition on the Properties of Duplex Stainless Steels

  • Hwangbo, D.;Yoo, Y.R.;Choi, S.H.;Choi, S.J.;Kim, Y.S.
    • Corrosion Science and Technology
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    • 제21권4호
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    • pp.273-281
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    • 2022
  • The effect of addition of Cu on the localized corrosion performance of aged duplex stainless steel in chloride media has yet to be explained in a consistent manner, and there is some controversy in the literature regarding the composition of stainless steel and the experimental conditions (pH, temperature, chloride concentration, etc.) used. In this work, the effect of the addition of Cu on the microstructure, hardness, and corrosion resistance of duplex stainless steel in an acidic chloride or high concentration sulfuric acid solutions was investigated for annealed and aged alloys. The Cu addition of annealed duplex stainless steel strengthened the alloy and reduced the ferrite contents of the alloy, and it also increased the polarization behavior in chloride or sulfuric solutions, except for the case of a high potential in acidic chloride solution. However, the Cu addition of aged duplex stainless steel reduced the formation of harmful phases such as sigma and kai and increased the polarization behavior in acidic chloride or sulfuric solutions up to 0.8 wt% of the Cu content, after which it slightly decreased at 0.8 wt% Cu or more.

자외선조사에 의해 유도된 도열병균의 승홍에 대한 내성에 관하여 (Tolerance of the Mutants of Pyricularia oryzae against Mercuric Chloride)

  • 김경호
    • Journal of Plant Biology
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    • 제22권3호
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    • pp.85-91
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    • 1979
  • Tolerance against mercuric chloride in mutants of Pyricularia oryzae Cavara induced by ultraviolet(UV) irradiation has been investigated. The tolerant isolates obtained using ultraviolet(UV) irradiation were maintained a high level of tolerance even after 15 times transfer to the chemical free media. Each isolate of mutants UM-1, UM-2, and UM-3 on the successive monoconidial culture has genetically homogeneous for tolerance. The tolerant isolates sporulated less and showed a higher percentage of germination of conidia on media without the chemical than the parental isolate. The xotins released from the parental and the tolerant isolates have been identified as piricularin and $\alpha$-picolinic acid by paper-chromatography. The tolerant isolates produced more piricularin and its virulence on seedlings of rice varieties were higher than the parental isolates. Both piricularin production and virulance on rice were highest in the UM-2 isolate.

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Microwave Heat Dyeing of Polyester Fabric

  • Kim, Sam-Soo;Lee, Su-Gyung m;Ghim, Han-Do;Kim, Joon-Ho;Lyoo, Won-Seok
    • Fibers and Polymers
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    • 제4권4호
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    • pp.204-209
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    • 2003
  • The effect of padding solution on the microwave heat dyeing of polyester fabric was studied extensively. Polyester fabrics were impregnated in aqueous urea solution and aqueous sodium chloride solution for 10 min and then dyed for 7 min by microwave apparatus (2450 MHz, 700 W) under optimum conditions which provide good exhaustion. Aqueous solutions of urea and sodium chloride showed more effective than water as a padding solution for microwave heat dyeing. The type of solvent added in padding media and its concentration significantly affects the K/S values of dyed polyester fabric. Added solvents such as n-hexane, acetone, and dimethyl formamide were also more effective than 100 % water as padding media for the microwave heat dyeing. It is supposed that the effect of used solvents on dyeing property of polyester fabrics depends on the solubility parameter difference between solvent and polyester fabric.

비에테르성 용매중에서 에테르촉매를 사용한 그리냐르반응에 의한 유기스탄닐화합물의 합성 (The Syntheses of Organostannyl Compounds by Grignard Reaction Catalyzed by Ether in Non-ethereal Media)

  • 서배석;이일규
    • 대한화학회지
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    • 제23권6호
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    • pp.392-395
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    • 1979
  • 몇가지 유기할로겐화물, 즉 브롬화에틸, 염화부틸, 브롬화페닐 및 염화벤질등을 탄화수소중에서 그리냐르법으로 무수사염화주석과 반응시켰다. 이때 소량의 에테르를 그리냐르반응단계에서 계내에 투입하엿을 때 보다 용이하게 반응이 진행되어 좋은 수율로 유기주석화합물들을 얻을 수 있었다.

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Microwave가열에 의한 Polyester직물의 염색성에 관한 연구(II) (A Study on the Dyeing of Polyester Fabric by Microwave Heating(II))

  • 임수경;김삼수;허만우
    • 한국염색가공학회지
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    • 제11권3호
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    • pp.49-57
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    • 1999
  • The effect of padding solution for the microwave heat dyeing of polyester fabric was studied variously. The dyeing property of polyester fabric varied with the kinds of added chemicals in the padding solution. Polyester fabrics impregnated in aqueous urea solution and aqueous sodium chloride solution for 10 minutes and then dyed for 7 minutes by microwave apparatus(2450 MHz, 700 W) under optimum conditions give good exhaustion. An aqueous solution of urea and a sodium chloride solution was more effective than water as padding solution for microwave heating dyeing. The K/S values of dyed polyester fabric by microwave were significantly affected by the type of solvent added in padding media and its concentration. Added solvents, n-hexane, acetone and dimethyl formamide were also more effective than water as padding media for the microwave heating dyeing. It is assumed that the effect of used solvents on dyeing property of polyester fabrics depends on the solubility parameter difference between solvent and polyester fabric.

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수직관형(垂直管形) 축열조(蓄熱槽)에서의 수화염류(水化塩類)의 상변화(相変化)를 이용(利用)한 열저장(熱貯藏)에 관(関) 연구(硏究) (A Study on the Heat Storage Utilizing Phase Change of Salt Hydrates in Vertical Piped-Storage System)

  • 연광석;차균도
    • Journal of Biosystems Engineering
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    • 제9권2호
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    • pp.74-80
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    • 1984
  • 시설규모(施設規模)가 작은 축소형(縮少型) 열저장장치(熱貯藏裝置)를 개발(開發)하기 위한 기초적(基礎的)인 연구(硏究)로 비교적(比較的) 열흡수능력(熱吸收能力)이 큰 염화칼슘, 황산(黃酸) 나트륨, 산성인산(酸性燐酸)나트륨 등(等)의 수화염류를 축열매체로 한 수직관형축열조(垂直管形蓄熱槽)를 제작(製作)하고 이들 축열장치(蓄熱裝置)를 이용(利用)한 축열매체의 열저장특성(熱貯藏特性)을 실험(實驗)을 통(通)하여 구명(究明)하기 위하여 수행(遂行)되었으며 그 결과(結果)를 요약(要約)하면 다음과 같다. 가. 수직관형축열조(垂直管形蓄熱槽)에서 반경방향 온도분포를 검토한 결과(結果), 본(本) 실험(實驗)에 사용(使用)된 모든 열매체는 가열과정(加熱過程)에서는 결정수(結晶水)의 감소(減少)로 인(因)한 발열현상(發熱現象)때문에 잠열현상(潛熱現象)이 나타나지 않았으나 냉각시(冷却時)에는 이들 축열매체중 염화칼슘이 가장 뚜렷한 잠열현상(潛熱現象)을 보였으므로 상변화를 이용(利用)한 축열매체로서 가장 적합(適合)하다고 사료(思料)되었다. 나. 가열(加熱) 및 냉각시(冷却時) 축열매체에 전달된 열량(熱量)은 같은 조건하(條件下)에서 염화칼슘의 경우(境遇)가 가장 많았다.

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항암제(然癌劑) 제형(劑形) 개발(開發)에 관(關)한 연구(硏究) : Silicone Rubber-수용성(水溶性) 첨가제(添加劑)의 Device에서 5-Fluorouracil의 용출(溶出) (Studies on Dosage Form Design of Anticancer Drug: Release of 5-Fluorouracil from Silicone Devices Containing Water Soluble Additives)

  • 김성호;최준식;백내선;유영종;이치영
    • Journal of Pharmaceutical Investigation
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    • 제16권1호
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    • pp.1-7
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    • 1986
  • The influences of sodium chloride, polyethylene glycol 4000 and 20000 on 5-fluorouracil release from disk type silicone polymer devices were examined in isotonic phosphate buffer. These water soluble cosolvent and sodium chloride caused devices to swell in aqueous media. Sodium chloride exerted the greatest influence on drug release. The addition of water soluble cosolvent or sodium chloride to silicone polymeric devices permitted controlled release of 5-fluorouracil, presumably due to the change of the physical microstructure of silicone network, and the solubility and diffusivity of 5-fluorouracil. It seemed that the water soluble drug was released through the hydrophilic pores or pathways formed in the device by the incorporation of a water soluble cosolvent or sodium chloride.

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수분이 NaKZn-Chloride의 녹는점과 고온안정성에 미치는 영향 (Effect of Moisture on the Melting Point and High-Temperature Stability of NaKZn-Chloride)

  • 이정환;김영;윤석호;이공훈;최준석
    • Korean Chemical Engineering Research
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    • 제56권4호
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    • pp.555-560
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    • 2018
  • $NaCl-KCl-ZnCl_2$ 혼합물(NaKZn-Chloride)의 열물성을 조사하여 열저장 매체로서의 잠재성을 평가하였다. 고온용 축열물질로 이용하기 위해서는 축열온도 범위에서 안정된 열물성을 유지하여야 하는데, 사전실험 결과 해당 혼합물은 알려진 고온안정온도인 $850^{\circ}C$ 보다 훨씬 낮은 온도에서 급격한 분해가 진행되었다. 이에 본 연구에서는, 흡수된 수분에 의해 축열물질의 열적 성질이 변화되는지 확인하고자 하였다. 혼합물의 수분함량에 따라 열물성이 변화되는 지를 열물성 장비로 측정하였으며, 가열-냉각 반복실험을 통해 다시 한 번 확인하였다. 그 결과 녹는 점의 경우 흡수된 수분에 관계없이 일정하지만, 고온 안정성의 경우 흡습한 샘플에서 다소 낮아지는 것을 알 수 있었다. 본 연구결과에 따라 흡습성을 가지는 고온 축열물질을 사용하는 시스템에서 수분과의 접촉을 줄임으로써 축열물질의 손실을 줄일 수 있다.