• 제목/요약/키워드: Thought Experiment

검색결과 500건 처리시간 0.031초

MBR공정에서 내부 반송비에 따른 생물대사성분의 거동 (Behavior of Soluble Microbial Products by the Internal Recycle Rate in MBR Process)

  • 이원배;차기철;정태영;김동진;유익근
    • 한국물환경학회지
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    • 제21권6호
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    • pp.602-608
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    • 2005
  • A laboratory-scale experiment was conducted to investigate control of soluble microbial products (SMP) by the internal recycle rate in the submerged membrane separation activated sludge process. The internal recycle rate of the reactor RUN 1 and RUN 2 were 100 % and 200 %, respectively. SMP concentration was rapidly accumulated in the reactor (RUN 1). The variation of accumulated SMP concentration was related to the denitrification rate at the beginning experiment however SMP concentration decreased without correlatively to the denitrification rate during long operation time. The microbial kinetic model was rapidly presented in the both microbial growth and extinction in the reactor (RUN 1). In the SMP kinetic model, Internal recycle rate is the lower, value of UAP and BAP which SMP matter were presented low. The study about development of kinetic model is relatively well adjusted to the experiment exception SMP. In the future, SMP formation equation must be thought that continually research is necessary.

땅콩 품질에 관한 연구현황과 금후의 방향 (Review of the Studies on the Qualities in Peanuts)

  • 이정일;박희운;한의동
    • 한국작물학회지
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    • 제33권s01호
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    • pp.64-85
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    • 1988
  • Peanut seeds are characterized by high oils and proteins with good quality, and are utilized as an edible oil source and a protein-rich food products. The end products, being peanut butter, salted seed, confections, roasting stock and other by-products are favored in world-wide because of their unique roasted peanut flavor. As with many other foods, interest in the composition and chemistry of peanut is largely a result of thier use as human food. Thus, a more complete knowledge of thier chemical and food quality and flavor properties is desired. Literatures are reviewed mainly focucing on the physicochemical properties and nutritional quality of oil, protein and flavor in peanuts. Chemical properties of protein and oil, and volatile flavor component in peanut seeds are studied extensively in view point of chemical and food nutritional value. But in crop base, the synthesis and genetic studies of the chemicals could not provide valuable informations on the breeding for quality improvement. Some essential amino acids are limiting in peanut seeds and the tocopherols are very important in oil stability and for dietary adequacy ratio in high linoleic acid peanut oil, but it is thought to be quite difficult to improve by breeding technique as their lack information of gene actions. However, the selections of high protein and oil, and some essential amino acids and linoleic acid rich genotypes could be helpful for the quality improving. Research studies are also needed to elucidate the relationships between flavor components and consumer perception of peanut flavor.

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우리나라 과학캠프의 운영 실태와 교육적 효과 (The Present Operational Status and Educational Effects of Science Camp in Korea)

  • 김성원;이현경
    • 한국과학교육학회지
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    • 제16권2호
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    • pp.175-189
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    • 1996
  • There is a growing tendency that it gives the first primacy to inquiry learning as lesson style from lecture or simple experiment in present primary. middle and high school. But in fact. inquiry learning is difficult due to space limit, lack of laboratory, instruments and program for inquiry learning. Therefore, it is very important for science camp which stimulates much interest in science to be activated by doing of scientific activities in out-of-doors. This study is to investigate the present operational status and educational effects of science camp in which Korean and American students and teachers found. The science camps held by Seoul YMCA Chong-Ro BR. and Dongdaemun BR., Bun-Dong middle school, and Cho-Sun IL BO and Inkel corp., were analyzed. The 284 students and 12 teachers who take part in science camps in Seoul YMCA Chong-Ro BR. and Bun-Dong middle school, and 197 students who attending in 6 schools in seoul were questionaired. The 37 American students and 16 teachers in Pennsylvania, were also questionaired, Most students and teachers thought it useful regarding science-program which proceeded at science camps. And it was thought that science program had much relation to science class in school, especially science-camp made it help to arouse interests on science.

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수분공급조절이 질경이 ( Plantago asiatica L. ) 의 생장에 미치는 영향 (Effects of Different Soil Moisture on the Growth of Plantago asiatica L.)

  • Lee, Ho Joon;Soon Ja Kim;Hae Won Kang
    • The Korean Journal of Ecology
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    • 제6권3호
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    • pp.227-235
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    • 1983
  • This research was made over drought resistance and optimum soil moisture needed with Plantago asiatica L. as the material by means of making out the process of its growth under different soil moisture contents. The soil used for the experiment was a mixture of vermiculite and c-layer soil, and the process of growth was compared with each other controlling its soil mositure as: 7%, 15%, 30%, 45%, and 60%. In 7% range of soil moisture which was of low content, the increase of growth was neither significantly indicated nor any permanent seeding done. In view of this phenomenon, Plantago asiatica L. appeared to be highly drought-resistant. It was found rising at 30% range and reaching the optimum state at 45% range and falling down at 60% range range. In viw of this fluctuation indicated above, the optimum soil moisture content needed for the growth of Plantago asiatica L. is thought to be between 30% and 60%. It is thought the number of seed per capsule is not affected by the soil moisture content. It is expected an ecotypic variation by the soil moisture content will bring forth upon Plantago asiatica L.

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사람의 배양세포염색체의, 방사선감수성에 관한 연구 (Studies on the Radiosensitivity of the Chromosomes in Cultured Human Cells)

  • 강영선;김영진;이정길
    • 한국동물학회지
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    • 제10권1호
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    • pp.17-20
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    • 1967
  • The present experiment was perform to investigate the frequencies of chromosome aberration with special regard to the chromosome groups and the various time intervals after X-irradiation (60 r) in ormal human foetus cells grown in culture. The cytological preparations were prepared at every 5 through 30 hours after X-irradiation by the air-drying method. 1. The frequencies of chormosome aberration are on the whole decreased as tie elapses after irradiation and this is thought to be due to gradual recovery with time . However, a slight increase in frequencies is observed at 25 and 30 hours after irradiation respectively. This shows that the cells at the these periods are more sensitivity to X-irradation , and those cells are thought to be at G$_2$ and late S stage at the time of irradiation respectively, so t is evident that G$_2$ and late S stages a the time of irradiation respectively , so it is evident that G$_2$ and late S stages are more sensitive to X-irradiation than any other stages. 2. The frequencies of chormosome aberration are decreased in descending order of chormosome group number. The differences among these frequencies are highly significant statistically . Therefore it can be concluded that there is a highly significant difference in radiosensitivity among chromosome groups. that is, the chromosomes of the group A are the most radiosensitive , followed by B, C, D ,E and G in descending order.

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오존을 이용한 수조속의 오염물질 제거특성에 관한 실험적 연구 (A study on sanitary emprical for specific property removal of pollution material inter a water tank by ozone)

  • 이관영;안승섭;박상현
    • 한국산업융합학회 논문집
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    • 제5권1호
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    • pp.75-80
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    • 2002
  • In this study, the initial number of bacteria before ozone sterilizing shows 290 per $1m{\ell}$ in RUN 1 and RUN 2 equally, but the removal rate shows more than 50% in RUN 1, and 100% in RUN 2 respectively when ozone injection amount is $0.28mg/{\ell}$. It is regarded as a satisfactory result that E-coli concentration without ozone contact is 890, rapid removal effect of E-coli is observed in $0.28mg/{\ell}$ of ozone, and E-coli is removed perfectly in $0.84mg/{\ell}$ of ozone. It is thought that an excellent efficiency is obtained for vibrio alginolyticus because the initial number of bacteria before ozone contact is positive, but it is altered to negative after ozone contact. CODcr shows the tendency which is somewhat reduced as the ozone injection is increased, but the general effect is appeared not so much, and it is thought that the tendency is caused by the reason that sea water contains much salt which is estimated as a component of CODcr, therefore it is regarded that ozone contact has not an important effect on salinity. It is thought that the frequency of changing salt water in the fish preserve of a sliced raw fish restaurant can be reduced to under the standard because NTU of 7 days after sea water injection is 0.70 in the experiment of turbidity, hut more than 50% of turbidity removal efficiency is appeared at $0.28mg/{\ell}$ of ozone injection, and it shows 70% at $0.84mg/{\ell}$ of ozone injection in RUN 1 and RUN 2 commonly.

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퍼텐셜 에너지 곡선에 대한 예비 화학 교사들의 이해 조사 (Pre-service Chemistry Teachers’ Understanding of the Potential Energy Curve)

  • 박종윤;김은경
    • 대한화학회지
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    • 제59권6호
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    • pp.508-519
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    • 2015
  • 본 연구에서는 개념 질문지를 사용하여 퍼텐셜 에너지 곡선에 대한 예비 화학 교사들의 이해 정도를 조사하였다. 조사 대상은 화학교육을 전공하는 사범대학 3학년 학생 24명, 4학년 학생 26명으로 총 50명이었다. 개념 질문지는 구슬 두 개의 거리에 따른 퍼텐셜 에너지 변화 곡선을 주고 상상실험을 하는 것으로 구성하였다. 질문지의 응답을 분석한 결과 예비 화학 교사들은 퍼텐셜 에너지나 전체 역학적 에너지가 음의 값을 가지는 것을 받아들이기 어려워하였다. 또한 역학적 에너지 보존은 대부분 알고 있었으나 이를 상상실험의 조건에 제대로 적용하지 못하는 것으로 나타났다. 그리고 구슬에 작용하는 힘의 방향은 대체로 알고 있었으나, 초기 위치에서 구슬이 이동하여 퍼텐셜 에너지가 가장 낮은 우물 바닥에서 정지할 것이라는 응답이 상당히 많았다. 또한 퍼텐셜 에너지 곡선과 관련지어 화학 결합, 기체의 액화, 분자의 진동 운동에 대한 이해도가 매우 낮은 것으로 드러났다.

소집단 실험활동에 나타난 중학생 질문 - 응답의 유형과 빈도 (Types and Frequencies of Questions - Answers by Middle School Students in a Small Group Activities During School Experiments)

  • 이명숙;조광희;송진웅
    • 한국과학교육학회지
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    • 제24권2호
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    • pp.277-286
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    • 2004
  • 소집단 실험활동에서 학생간 질문의 유형과 빈도를 파악하기 위하여, 서울소재 여자중학교 1학년 학생 5명의 실험수업을 관찰하고 관찰학생을 면담하였다. 소집단 실험활동에서 학생간 질문을 분석한 결과, 사고형 질문보다 정보형 질문의 빈도가 높았다. 정보형 질문의 대부분은 실험과정이나 결과를 묻는 절차질문이었다. 사고형 질문의 대부분은 결과를 해석하면서 잘 이해되지 않은 부분에 대하여 설명을 요구하는 이해질문이었다. 드물게 변칙발견질문이 제기되었으나 학습을 위한 토론으로 이어지지 않았다. 그리고 2인1조로 활동을 한 경우에 5인1조의 경우보다 응답률이 높았고, 도움을 받는 질문의 비율도 높았다. 2인1조 활동에서는 성취도가 상대적으로 낮은 학생이 질문하고 성취도가 높은 학생이 응답하는 경향이 두드러졌다. 또 구성원의 성취도 차이가 큰 조에서는 질문의 빈도가 낮게 나타났으며, 구성원의 성취도 차이가 적은 조에서는 성취도에 따라 질문 유형의 차이가 나타났다. 결론적으로 소집단 실험활동에서 제기되는 학생간 질문은 사고형 질문보다 정보형 질문의 빈도가 높으며, 구성원의 수가 적을 때 응답을 통해 도움 받는 질문의 비율이 높았다.

스트레스에 의한 혈당변화가 타액선내 Clusterin 발현에 미치는 영향 (Clusterin(SGP-2) in the Salivary Glands of Insulin Injected Rats under Stress)

  • 김선호
    • Journal of Oral Medicine and Pain
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    • 제23권4호
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    • pp.309-326
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    • 1998
  • In general, the major causative factor of halitosis is thought to be a sulfated compounds. Clusterin, a sulfated glycoprotein-2(SGP-2), is frequently found in diabetic conditions and cold stress conditions. The same result is werum glucose level to diabeteic and cold stress conditions that founded Clusterin. Therefore, this study was performed to examine Clusterin in the slivary glands under stress conditions before insulin injection I.M. Fourty rats were diveded into 3 groups ; 1) 10 rats of gorup I were selected as a control 2) 15 rats beloning to group II were bathed in cold water for 30 seconds twice a day 3) 15 rats in group III received cold stress and injected I.M. with insulin. The rats were sacrifeced at day 0, 3, 5, 7 and 10 of the experiment and the submandibular glands and parotid galnds were removed. RNAs were purified from the salivary of the salivary glands were subjected to Hematoxillin-Eosin stainings and examined under the light microscope. The obtained results were as follows : 1. With immunohistochemistric method, in normal control goup, Clusterin was moderately stained in the intercalated ductal cell of the submandibualr glands, mild stained in the striated ductal cell of the submandibular glands, heavily stained on the cytoplasm of the intercalated ductal cell in the mucous submandibular glands nad slightrly stained in the intercalated ductal cell of the paroted gland, expressed negativity in the acina cell. 2. With immunohistochemistric method, Clusterin slightly increased in the acina cell of the submandibular glands under stress condition at 3 days after experement, moderately stained at 5 days after experiment so revealed positive response. And hearily in the intercalated ductal cell and mildly lin the acina celluar eytoplasm of the parotid glands under stress condition at 3 days experiment. 3. With immunohistochemistric method, no remarkable differences are found between the normal control group and stress conditioned group that insulin administration was performed before. 4. In the stressor-giving group, Clusterin mRNA was porminently expressed in submandibular gland after 5 days after experiment, in parotid gland after 3 days after experiment, performed in immunoelectrophoresis method. 5. In the insulin-injected nad stressor-giving group, Clusterin mRNA was not observed in all experimental submandibular and parotid gland, performed in immunoelectrophoresis method.

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중학교 과학교과서, 교사의 인식 및 실험 수업 사례에서 나타난 과학적 탐구 요소 분석 (Analysis of Scientific Inquiry Elements in Middle School Science Textbooks, Teachers' Cognition, and an Experiment Case)

  • 한유화;전은선;백성혜
    • 한국과학교육학회지
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    • 제34권4호
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    • pp.349-357
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    • 2014
  • 이 연구의 목적은 수업시간에 이루어지는 과학 실험의 의미를 고찰하고 실험 수업의 개선 방향을 알아보는 것이다. 이를 위하여 교과서, 교사 인식, 실제 수업 사례를 분석하여 탐구 요소가 과학 실험 수업에 얼마나 포함되어 있으며 그 수준은 어떠한지 알아보았다. 22명의 교사를 대상으로 한 설문지를 통해 교사의 인식을 알아보았으며, 중학교 3학년 2개 학급의 2차시 수업을 분석하였다. 연구 결과, 문제제시, 증거수집, 현상설명 및 기존 과학지식의 연결은 대부분의 교과서에서 제시되었으나, 의사소통 및 정당화 요소는 많지 않았다. 또한 제시된 수준은 주로 교사 주도적이었다. 교사들은 의사소통 및 정당화 단계가 매우 중요하다고 생각하였으나, 실제 실험 수업에 이를 반영하지는 못하는 것으로 나타났다. 실제 실험 수업에서 학생들은 시간의 대부분을 증거수집에 할애하였으며, 실험 결과인 증거를 기반으로 현상을 설명하거나 기존 지식과 연결하는 활동, 그리고 의사소통 및 정당화의 활동은 거의 하지 못하였다.