• 제목/요약/키워드: EE2

검색결과 935건 처리시간 0.025초

제올라이트-효소 촉매를 이용한 ρ,α-Dimethyl Benzyl Alcohol의 2상 동적 속도론적 광학분할 (Biphasic Dynamic Kinetic Resolution of ρ,α-Dimethyl Benzyl Alcohol over Zeolite-Enzyme Catalysts)

  • 차연주;고문규;박융호
    • 공업화학
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    • 제17권6호
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    • pp.658-664
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    • 2006
  • $\rho$, $\alpha$-dimethyl benzyl alcohol을 효과적으로 분할하기 위하여 2상 동적 속도론적 광학분할(biphasic dynamic kinetic resolution, DKR)반응을 실시하였다. 라세미화 반응을 위하여 촉매로 산성 제올라이트를 사용하였고 속도론적 광학분할(kinetic resolution, KR)을 위하여 고정화 효소를 촉매로 사용하였다. 유기용매와 물을 용매로 사용하는 이상 DKR 반응에서, acyl donor, 반응온도, 기질의 농도, 두 가지 촉매의 상대적 비율 및 교반속도 등의 공정변수를 변화시켜가면서 DKR반응의 전환율과 생성물의 광학순도에 미치는 영향을 조사하였다. 그 결과, $\rho$, $\alpha$-dimethyl benzyl alcohol의 DKR 반응에서 99% 이상의 광학순도를 가지는 생성물을 최대 88%의 높은 수율로 얻을 수 있었으며, 높은 TON에서도 반응의 효율성이 유지되었고 촉매의 재사용 시에도 지속적인 활성을 나타내었다.

신기환 약침이 HiB5 해마세포와 어린 Sprague-Dawley계 흰쥐의 치상회 세포생성에 미치는 영향 (Shenqi-wan Increases Cell Proliferation of Cultured Hippocampal Cell Line HiB5 and Dentate Gyrus of Young Sprague-Dawley Rats)

  • 김연정;장미현;신민철;임백빈;정주호;반건호;백은경;박재형;김이화;김창주
    • Korean Journal of Acupuncture
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    • 제19권1호
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    • pp.77-84
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    • 2002
  • 목적 : 소아의 정신적 및 신체적 발달지연에 사용되고 있는 신기환이 해마의 신경세포 생성에 미치는 영향을 관찰하고자 하였다. 방법 : 신기환이 세포생성에 미치는 영향을 알아보기 위하여 해마 세포인 HiB5에 신기환을 처리, 배양하여 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay를 통해서 세포생성을 관찰하였다. 또한 3주령의 Sprague-Dawley (S-D)계 흰쥐의 중완혈에 신기환 약침을 자침후 해마의 치상회에서 bromodeoxyuridine (BrdU) immunohistochemistry를 시행하여 세포생성을 관찰하였다. 결과 : HiB5 배양세포에서는 신기환을 처리시 배양시간과 농도별로 세포생성율이 증가하였다. 또한, 대조군의 치상회에서 BrdU 양성세포수는 $128.50{\pm}9.53$, 1 mg/kg 신기환 자침군은 $157.08{\pm}10.82$ 및 10 mg/kg 신기환 자침군은 $204.80{\pm}17.68$로 나타났다. 이러한 결과로 신기환은 어린 S-D계 흰쥐의 치상회에서 세포생성을 증가시키는 것으로 사려된다.

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소형실험태양(小型實驗太陽)연못에서 열저장층(熱貯藏層)의 두께에 관(關)한 실험적(實驗的) 연구(硏究) (Experimental Study on Thicknesss of Heat Storage Zone in Small Solar Pond)

  • 박이동;서지원
    • 태양에너지
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    • 제7권2호
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    • pp.22-29
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    • 1987
  • This paper dealed with thickness variation of bottom heat sotrage zone due to salinity and flow rate of extration hot brine in small test solar pond (0.5m wide, 0.5m high, 1.0m long). Testing apparatus and situation were follows: 7.1 cm of height of suction diffuser and 1.8cm of height of discharge diffuser above the test pond respectively, 0.3cm of slot size of suction diffuser, 1.0cm of slot size of discharge diffuser, 47cm of length of the slot; heating of hot water ($75^{\circ}C$) through separated hot water tank, discharge of the brine into storage zone through discharge diffuser, the extration of the brine through suction diffuser, circulation of the extracted brine through a heat exchanger (cooler). Following results were obtained through the experiments. 1. In small test solar pond, the typical three zone which showed up in real solar pond were established. 2. Richardson Number was used more effectively to confirm hydrodynamic stability of the stratified flow. 3. The thickness of non convective layer had a great effect on the heat storage of the bottom convective layer, then the temperature of bottom convective layer had a relation to that of upper convective layer. 4. Optimum operating condition in the test pond was on 10%-15% of salt concentration and $0.05m^3/hr$ of flow rate of extraction hot brine. 5. Following thickness of 3 zones were available to obtain under optimum operation condition: o bottom storage zone: $30%{\pm}10%$ of total pond depth o non-convective zone: $40%{\pm}10%$ of total pond depth o Upper surface zone: $20%{\pm}10%$ of total pond depth.

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Caffeine 및 광자극 유발 스트레스 동물모델에서 구기자 복합물이 스트레스 완화 및 혈중 멜라토닌에 미치는 영향 (Effect of Herbal Mixture including Lycii Fructus (HML) on Stress Relief and Melatonin in Caffeine and Light induced Stress Animal Model)

  • 김이화;황동석;김희택;김용민
    • 한방안이비인후피부과학회지
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    • 제33권4호
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    • pp.44-54
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    • 2020
  • Objectives : In the present study, we investigated whether or not an herb mixture including Lycii fructus(HML) has attenuation effects on light stress in rats. Methods : Light stress was induced by exposure to 300 lx of constant lifht for 24 h and 1mg/kg of caffeine was injected into the rat. Rats were orally treated with distilled water of HML for 21 days at 100mg/kg/d. The changes of mortality rate, clinical signs, body, blood chemistry, melatonin and IL-2 expression were analyzed after experiment. Results : Normal weight changes were observed in all treatment groups. In addition, no changes were observed in dead animals and general symptoms. At the time of autopsy, the appearance of all groups and gross examination of major organs were observed, and no gross findings were observed. Blood biochemical tests showed that total cholesterol and HDL cholesterol levels were statistically significantly decreased in the group treated with HML compared to the stress-induced group. Melatonin was measured in the blood, but there was no significant difference in the group treated with HML compared to the group with stress-induced group, but it tended to increase. IL-2 was measured in the blood, no significant change was observed in the group treated with HML compared to the stress-induced group. Conclusions : According to the above results, HML maybe help with hematological changes expressed by caffeine and light-induced stress.

주거용 태양열 성층축열시스템의 시뮬레이션 (A Simulation for the Stratified Thermal Storage System in Residential Solar Energy Application)

  • 박이동;유호선
    • 태양에너지
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    • 제11권3호
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    • pp.44-52
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    • 1991
  • 본 연구의 목적은 주거용 태양열 온수이용에 있어서 성층저장의 잠점을 평가하고 최적의 설계변수를 제시하되 실험이 아닌 시뮬레이션을 통한다는 것이다. 그 결과는 다음과 같으며 실험의 결과들과 잘 일치함을 보였다. 1. 탱크의 성층분활이 증가함에 따라서 태양부하율이 증가함을 보여 주었고 본 연구에서는 평균 10% 정도 증가함을 나타내었다. 2. 저장탱크의 높이 대 지름의 비가 3정도일 때가 태양부하율이 최대가 되었으며 그 이상이 되면 감소하는 경향을 나타내었다. 3. 집열기로 부터 저장탱크로 유입되는 온수의 유동율이 증가할 수록 완전혼합저장에서는 태양부하율이 증가하지만 성충저장에서는 유입율이 감소하는 것이 태양부하율을 증가시키는 결과가 되었다. 4. 이와 같은 결과로 성층축열시스템 전체적으로는 약 17%의 성능 향상을 기대할 수 있다.

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일 지역주민의 질병예방 행위 및 건강증진행위에 관한 연구 -거제지역 중심으로- (A Study on Health Promoting Behavior and Disease Preventive Behavior of a Community Residents - Koje area-)

  • 김금이;임미영
    • 지역사회간호학회지
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    • 제12권1호
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    • pp.168-174
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    • 2001
  • This study was conducted to investigate the disease preventive behavior and health promoting behavior of a community residents. The subjects were selected by convenient sampling and the total number was 300(Female, 170, Male, 130). The data were collected by face to face interviews during the period of Sep. 15-30, 1999. The measurement tool for this study was the rating score for disease preventive behavior and health promoting behavior. The instrument was developed by the researcher based on the tool of Korea Institute for Health and Social Affairs. The data were analyzed by percentage, mean, t-test, ANOVA. $x^2-test$ by Windows SPSS/PC program(v7.5). The results were as follows: 1. In the comparison of disease preventive behavior rates between male and female, there was a statistically significant difference in physical examination, measuring the blood pressure and vaccination for B type hepatitis. In the comparison of disease preventive behavior rates among the age, there was a statistically significant difference in physical examination, measuring the blood pressure. 2. The rating score for the health promoting behavior of the men subjects was lower than that of the women subjects. In the comparison of health promoting behavior scores between male and female, there was a statistically significant difference in smoking, drinking, regular exercise, breakfast eating, vegetable consumption and teeth brushing. In the comparison of promoting Behavior scores among the age, there were significant difference, there was a statistically significant difference in smoking, sleeping, seat belt use, breakfast eating and salty eating.

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닷넷 리모팅 환경에서의 보안 방안 구현 (Implementation of Security Plan from .NET Remoting Environment)

  • 김영서
    • 융합신호처리학회논문지
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    • 제10권4호
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    • pp.256-261
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    • 2009
  • 최근의 웹환경은 닷넷과 자바로 양분되어 있다. 닷넷은 웹환경에서 원격의 객체를 호출하는 방법으로서 리모팅이라는 기술이 있다. 리모팅 기술 방식은 HTTP(Hypertext Transport Protocol)환경에서 데이터를 주고받는 원격호출의 한 형태로 SOAP(Simple Object Application Protocol)형태의 확장기술이다. 본 연구는 ERP(Enterprise Resource Planning)와 같은 잡한 업무의 웹프로그램에서 많이 사용하는 닷넷 리모팅 기술에서 ERP에 최적화한 응용계층 보안 적용, 리모팅 모듈과 암호화 모듈에서 중복되어 발생하는 직렬화 작업제거, 닷넷에서 사용되는 데이터 객체에 불필요한 데이터 제거를 통해 성능을 향상시키는 보안모듈 적용 방법을 제시하였다. 제시한 방법은 구현 및 실험을 통해 일반적인 보안적용에서 보다 약 2배의 속도 향상이 있음을 확인하였다. 향후 이와 관련된 컴포넌트 기반의 프레임워크 연구를 통해 편리한 개발자 환경 제공이 필요하다.

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Improved Biocompatibility of Intra-Arterial Poly-L-Lactic Acid Stent by Tantalum Ion Implantation : 3-Month Results in a Swine Model

  • Kim, Kangmin;Park, Suhyung;Park, Jeong Hwan;Cho, Won-Sang;Kim, Hyoun-Ee;Lee, Sung-Mi;Kim, Jeong Eun;Kang, Hyun-Seung;Jang, Tae-Sik
    • Journal of Korean Neurosurgical Society
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    • 제64권6호
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    • pp.853-863
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    • 2021
  • Objective : Biodegradable poly-L-lactic acid (PLLA) with a highly biocompatible surface via tantalum (Ta) ion implantation can be an innovative solution for the problems associated with current biodegradable stents. The purpose of this study is to develop a Taimplanted PLLA stent for clinical use and to investigate its biological performance capabilities. Methods : A series of in vitro and in vivo tests were used to assess the biological performance of bare and Ta-implanted PLLA stents. The re-endothelialization ability and thrombogenicity were examined through in vitro endothelial cell and platelet adhesion tests. An in vivo swine model was used to evaluate the effects of Ta ion implantation on subacute restenosis and thrombosis. Angiographic and histologic evaluations were conducted at one, two and three months post-treatment. Results : The Ta-implanted PLLA stent was successfully fabricated, exhibiting a smooth surface morphology and modified layer integration. After Ta ion implantation, the surface properties were more favorable for rapid endothelialization and for less platelet attachment compared to the bare PLLA stent. In an in vivo animal test, follow-up angiography showed no evidence of in-stent stenosis in either group. In a microscopic histologic examination, luminal thrombus formation was significantly suppressed in the Ta-implanted PLLA stent group according to the 2-month follow-up assessment (21.2% vs. 63.9%, p=0.005). Cells positive for CD 68, a marker for the monocyte lineage, were less frequently identified around the Ta-implanted PLLA stent in the 1-month follow-up assessments. Conclusion : The use of a Ta-implanted PLLA stent appears to promote re-endothelialization and anti-thrombogenicity.

위생탕(衛生湯)의 LPS로 유도된 RAW264.7 세포에서 염증매개체에 대한 억제효과 (Inhibitory Effects of Wisaengtang on Inflammatory Mediators in LPS-induced RAW264.7 Cells)

  • 김정희;김태준;김이화;김용민
    • 한방안이비인후피부과학회지
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    • 제32권3호
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    • pp.48-57
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    • 2019
  • Objectives : This study examined the inhibitory effects of Wisaengtang(WST) on inflammatory mediators($NF-{\kappa}B$, COX-2, iNOS, IL-6) in cellular inflammatory responses induced by lipopolysaccharide(LPS). Methods : To investigate the cytotoxicity of WST, MTT assay was used. The inhibitory effects of inflammatory mediators were confirmed by real-time PCR and DPPH scavenging activity was measured to confirm the antioxidative effect. Results : When the $NF-{\kappa}B$ mRNA expression was inhibited, the levels of COX-2, iNOS, and IL-6 mRNA in the inflammatory response decreased significantly. iNOS is involved in the production of nitric oxide (NO), and it is confirmed that WST inhibits the expression of iNOS mRNA and thus the production of NO. Conclusions : These results suggest that WST can be a therapeutic substance for oxidation and inflammation through elimination of DPPH free radical and inhibition of $NF-{\kappa}B$ activity.

NF-𝜅B억제를 통한 청심양격산(淸心凉膈散)의 항염증 효과 (Anti-inflammatory Effects of Cheongsimyanggyeok-san via NF-𝜅B Inhibition)

  • 김난이;김연수;지선영;황보민
    • 한방안이비인후피부과학회지
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    • 제32권2호
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    • pp.11-23
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    • 2019
  • Objectives : The purpose of this study is to investigate the anti-inflammatory effect of Cheongsimyanggyeoksan(CYS) water extract in vitro and in vivo. Methods : To evaluate the anti-inflammatory effect of CYS, Raw 264.7 cells were pretreated with $3-300{\mu}g/m{\ell}$ of CYS for 1h, and then exposed to $1{\mu}g/m{\ell}$ of LPS. The cell viability was detected by MTT assay. Productions of nitric oxide(NO) and pro-inflammatory cytokines were measured in culture media. Protein levels of inducible nitric oxide synthase(iNOS) and Nuclear factor-${\kappa}$B($NF-{\kappa}B$) were determined by immunoblot analysis. The effect of CYS on acute inflammation in vivo was evaluated thorugh measurment of carrageenan-induced paw edema. Results : In vitro study, cell viability assay CYS treatment of $3-300{\mu}g/m{\ell}$ has no cytotoxicity in Raw 264.7 cells. LPS-induced NO production was significantly inhibited by pretreatment with $30-300{\mu}g/m{\ell}$ of CYS. Production of interleukin-6, -$1{\beta}$ and tumor necrosis factor-${\alpha}$ by LPS were significantly decreased by CYS pretreatment. CYS reduced LPS-mediated iNOS expression. Moreover, CYS significantly induced $I-{\kappa}B{\alpha}$ expression and reduced $NF-{\kappa}B$ expression. In vivo study, CYS significantly reduced the increases of paw swelling. Conclusions : These results suggest the clinical basis of CYS for the treatment of inflammatory diseases.