• 제목/요약/키워드: Purging period

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맥동 효과를 이용한 dead-end type 연료전지의 성능향상에 대한 실험적 연구 (An experimental study on the performance improvement of dead-end type PEMFC with pulsating effect)

  • 최종원;서정훈;황용신;이대흥;차석원;김민수
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2008년도 동계학술발표대회 논문집
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    • pp.567-571
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    • 2008
  • PEM Fuel Cell operation mode can be classified into dead-end mode or open mode by whether the outlet port is blocked or not. Generally, dead-end type fuel cell has some merits on the pressure drop and system efficiency because it can generate more power than the open type fuel cell due to high operating pressure condition. However, the periodic purging process should be done for removing water which is formed as product of a reaction in the gas diffusion layer. In this study, cathode side dead-end type operation has been conducted. Moreover, pulsating flow generator at the outlet of cathode side has been suggested for increasing the period to purge the formed water because the pulsating flow can make formed water scattered uniformly over the whole channel. As a result, the purging period with pulsation increased by 1.5-2 times longer than that without pulsating.

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Preliminary pharmacological evaluation of an Ayurvedic formulation Dasamularista

  • Rajia Sultana;Choudhuri M Shahabuddin Kabir;Sattar Mafruhi;Shahriar Masum
    • Advances in Traditional Medicine
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    • 제6권3호
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    • pp.208-214
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    • 2006
  • In this study the Ayurvedic formulation Dasamularista was studied for its preliminary pharmacological properties using laboratory mice. Dasamularista showed a decrease in food intake and stool formation, while the water content of stool and water intake was higher and the volume of the urine was less. Dasamularista in a slight extent reduced the intestinal motility. This constipating effect was further supported by the significant anti-diarrhoeal property of the formulation in castor oil induced dairrhoea. The tested formulation markedly increased the latent period of diarrhoea and reduced the purging index value. Dasamularista did not alter the acetic acid induced abdominal writhing. Significant reduction on the onset of sleeping time and increased duration of sleep was observed in pentobarbital induced sleeping time test.

Some pharmacological findings of non therapeutic importance of an Ayurvedic preparation Chandanasav

  • Chakraborty, Sharmila;Rajia, Sultana;Choudhuri, M. Shahabuddin Kabir;Hossain, M. Faruk;Sattar, Mafruhi;Shrestha, Tripti
    • Advances in Traditional Medicine
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    • 제6권2호
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    • pp.157-160
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    • 2006
  • Chandanasav is an Ayurvedic preparation slightly reduced the gastrointestinal motility at the 15 min time interval. It increased the latent period of castor oil induced diarrhoea, slightly decreased number of stool count and lowered the purging index values. Chandanasav significantly reduced the onset and increased the duration of pentobarbital induced sleeping time. No significant analgesic effect was observed from the hot plate study Thus it may have mild constipating and central nervous system depressant activity without any effect on peripheral nervous system.

우울증(憂鬱症)의 임상양상(臨床樣狀) 및 생체전기자율반응에 대(對)한 임상적(臨床的) 고찰(考察) (A Clinical Study of Depression in 43 Cases)

  • 박지운;이상룡;최병만
    • 동의신경정신과학회지
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    • 제12권2호
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    • pp.37-51
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    • 2001
  • The clinical study was carried out the 43 patients with Depression who were treated in Department of Neuropsychiatry, College of Oriental Medicine, Dae Jeon University from 22 February 2000 to 14 November 2001. The results were summarized as follows. 1. The ratio of male and female was 10:33, 60's(32.6%) was frequent, no inducing factor(38.3%) was seen in a lot of cases and many patients came to our hospital by way of west-neuropsychiatry(56.8%). 2. The period of clinical history was frequent from 3 to 10 years(23.2%), the most frequent preceding disease was cardiovascular systemic disease(18.4%). 3. The main clinical symptoms were apprehension alpitation(13.4%), anorexia(9.8%), headache nuchal region stiffness(9.8%), general body weakness(6.5%), chest discomfort(6.5%), dizziness(5.7%), febris(5.3%) and constipation(5.3%). 4. The patient's tongue aspect had pink tongue and empty fur(32.6%) and pulse type had thin and deficient pulse(39.5%). The prescription drugs were Chunggansoyo-san(30.0%), purging liver and alleviating depression to regulate qi, and Guibiondam-tang(15.8%) eliminating phlegm, cooling pericardium and warming gallbladder. 5. The curve was within normal range at Psychoneural system(81.4%), and Visceral system(90.1%). 6. The regulation was Normal(48.1%), RL(27.9%), RR(20.2%) at Psychoneural system and Normal(45.9%), RL(28.5%), RR(20.3%) at Visceral system. 7. Activity and Reactivity had much lower response at 1th, 2th, 3th, 4th, 7th SANGHAN, Polalization had much higher response at 1th, 4th, SANGHAN and much lower response at 2th, 3th, 7th SANGHAN.

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불면(不眠)에 대한 침구치료(鍼灸治療)의 접근 방법론 연구 - 경락생리(經絡生理) 및 혈성(穴性)을 중심으로 - (A study of methods for Acupuncture and moxibustional treatment to Insomnia)

  • 김근우
    • Korean Journal of Acupuncture
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    • 제21권3호
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    • pp.147-158
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    • 2004
  • Objectives : This study was aimed to investigate the methods for acupuncture and moxibustional treatment to insomnia Methods : The insomnia is classified by seven cause at main subject. According to this, arrange the acupuncture and moxibustional treatment for classical books, and explain eight meridian related to insomnia. Results : 1. Insomnia means deficiency of sleeping and it is the word generally used when a short period of sleeping, difficulty for deep sleeping and difficulty for recovery of original vital energy comes out. In oriental medicine, they understand that uneasiness condition occurred by abnormal operation of the internal organs as heart, liver, gallbladder, spleen, stomach, kidney, etc. caused by external affection or internal injury becomes Insomnia. 2. Cause of insomnia can be classified majorly as fire-transformation of liver and gallbladder , inner shaking of phlegm-heat , insufficiency of both the heart and the spleen, disharmony between heat and kidney, the dysfunction of the stomach, timidity of heart and gallbladder, the deficiency of Qi of the lung. They make insomnia with bad influence upon body and spirit. 3. The meridian system such as Heart Meridian of Hand Soeum, Pericardium Meridian of Hand Gworeum, Stomach Meridian of Foot Yangmyeong, Spleen Meridian of Foot Taeeum, Bladder Meridian of Foot Taeyang, Kidney Meridian of Foot Soeum, Gallbladder Meridian of Foot Soyang, Liver Meridian of Foot Gworeum and Lung Meridian of Hand Taeeum are used to treat insomnia. Sinmun acupoint and Naegwan acupoint are often used in particular because the they are good for calmming the spirit, the heart and purging the heart of (pathogenic) fire. 4. Especialy, Back-Su points of Bladder Meridian of Foot Taeyang was used by each causes. The Back-su Points was mainly used for heal the insomnia because the Back-Su points has good competent to control the ability of internal organs by direct effect to it. It is because the vitality flows through around back-Su. Conclusions : It comes to a conclusion as follows with research for relevancy of the main cause of insomnia and meridian system includes meridian point.

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LPS로 활성화된 대식세포에서 황련해독탕(黃連解毒湯) 물추출물의 염증매개물질 억제효과 (Anti-inflammatory Effects of the Aqueous Extract of Hwangnyeonhaedok-tang in LPS-activated Macrophage Cells)

  • 김대희;박숙자;정지윤;김상찬;변성희
    • 대한본초학회지
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    • 제24권4호
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    • pp.39-47
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    • 2009
  • Objectives : Hwangnyeonhaedok-tang (Huanglian Jiedu Tang; HHT) has been widely used for purging' 'fire' and lessening virulence of any pathogenic organism. However it has been rarely conducted to evaluate the immuno-biological activity. In this study, we evaluated anti-inflammatory effects of HHT in LPS-activated Raw264.7 cells. Methods : Cells were treated with $1\;{\mu}g/ml$ of LPS 1 h prior to the addition of HHT. Cell viability was measured by MTT assay. The production of NO was determined by reacting cultured medium with Griess reagent. PGE2 and proinflammatory cytokines were detected by ELISA. Expression of iNOS, COX-2, $I{\kappa}B{\alpha}$ and NF-${\kappa}B$ were analyzed by immunoblot analysis. Results : All three doses of HHT (0.03, 0.10 and 0.30 mg/ml) had no significant cytotoxicity during the entire experimental period. The levels of NO and PGE2 were dramatically augmented by LPS compared to control. However, HHT extract dose-dependently reduced these increases. Expression of iNOS and COX-2 protein were also decreased by treatment with HHT extract. Furthermore, HHT extract significantly reduced the nuclear translocation of NF-${\kappa}B$ which is critical in regulating inflammation through transcription of iNOS and COX-2. In addition, HHT extract reduced the elevated production of inflammatory cytokines including TNF-$\alpha$, IL-$1{\beta}$ and IL-6. Conclusions : The results in this study demonstrate that HHT extract exerts anti-inflammatory activities through the inhibition of NO, PGE2 and proinflammatory cytokines production via the suppression of NF-${\kappa}B$.

Topiramate의 신경성 폭식증 치료효과: 국내외 보고된 임상연구결과 및 치험사례 중심으로 (Topiramate for the Treatment of Binge Eating Disorder or Bulimia Nervosa : A Systemic Review of Human Clinical Studies and Case Reports)

  • 이유정;방준석
    • 한국임상약학회지
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    • 제17권1호
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    • pp.6-12
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    • 2007
  • 지난 20 여 년 간 서구 선진사회에서는 식사장애(Eating disorder) 중에서 신경성 폭식증(Bulimia nervosa)의 발병률이 급격히 상승하였고, 우리나라는 특히 젊은 여성층에서 발병률이 빠르게 상승하고 있다. 치료약물로는 주로 항우울제가 선택되지만, 치료효과가 미흡한 바, 항경련제인 topiramate가 효과가 있다는 보고들이 있어 이를 신경성 폭식증치료에 적극 사용할 수 있는가에 관심이 고조되었다. 본 연구는 topiramate가 지닌 신경성 폭식증 치료효과에 대한 최신 지견을 얻고자, 1990년부터 2006년 사이 MEDLINE과, 한국의학논문데이터베이스에 등재된 국내외 자료를 binge eating disorder, bulimia nervosa, topiramate라는 3개의 주요어휘로 검색하여 추출한 자료중에서, 대조군이 사용된 무작위 배정, 이중맹검 임상연구 및 치험사례 만을 선별하여 임상적유용성을 평가하였다. 국외 임상연구 및 치험사례에 따르면, topiramate가 신경성 폭식증에 수반되는 유해한 증상의 발생빈도를 경감시키는데 유효함을 나타내었다. 국내에는 아직 topiramate의 신경성 폭식증 치료효과를 검증한 체계화된 임상연구나 치험사례가 보고된 바 없었다. 피험자의 규모가 작다는 한계에도 불구하고, 일일 투여량 25 mg로 시작하여 점차 증량후 최대 600 mg까지 투여한 국외의 연구결과는, topiramate가 신경성 폭식증 치료에 유효한 결과를 보인다고 사료되므로, 국내 신경성 폭식증 임상치료와 연구에 반영되기를 기대한다.

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수정진동자를 이용한 프탈로시아닌 LB박막의 $NO_2$ 감지 특성 (The Application of Octa-Substituted Metallophthalocyanine Langmuir-Blodgett films for $NO_2$ Measurement)

  • 권현정;이영진;장용근;김종득
    • 센서학회지
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    • 제7권4호
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    • pp.254-262
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    • 1998
  • 수정진동자(QCM)위에 네 종류의 프탈로시아닌($MPc(OEH)_8$, M ${\equiv}$ Cu, Co, Sn, $H_2$) LB박막을 여러 층 적층시킨 후 순수한 질소 분위기 하에서 $NO_2$에 노출시켜 그 농도를 정량화 하였다. 사용한 네 종류의 프탈로시아닌 중에서 중심위치에 금속 이온이 자리하지 않은 $H_2Pc(OEH)_8$ 감응막이 $NO_2$에 대하여 가장 민감한 것으로 나타났다. 그러나 이 박막은 $NO_2$에 노출된 후 질소로 퍼지해도 처음의 주파수를 회복하지 못하는 비가역적인 흡착 양상을 보였다. NMR과 FTIR 스펙트럼 조사 결과 비가역적인 흡착은 빙고링과 프탈로시아닌 곁가지의 결합부위인 ether 그룹에서 일어나는 것으로 판명되었다. 따라서 비가역적으로 흡착이 일어나는 부분을 미리 고농도에서 포화시키는 방법으로 박막을 전처리 한 후 반복실험에 사용하였다. $CuPc(OEH)_8$박막 사용 시 수십 ppm 수준부터 4 ppm의 $NO_2$ 농도까지 정량화가 가능하였고 $H_2Pc(OEH)_8$ 박막의 경우에는 수 ppm부터 35 ppb까지의 낮은 농도까지 정량화가 가능하였다. 또한, 실제 대기 조건을 모사하기 위하여 운반기체를 순수한 질소 대신 공기로 교체하여 $H_2Pc(OEH)_8$ 감응막의 성능을 실험한 결과 산소의 영향으로 센싱 가능 한계가 수백 ppb 수준으로 증가하였다. 습기가 운반기체에 포함된 경우 감지 성능에 매우 큰 영향을 미쳤다.

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