• 제목/요약/키워드: MI2U

검색결과 632건 처리시간 0.03초

Photopolymerization of Methyl Methacrylate with 1,4-$C_6H_4(SiH_{3-x}Me_x)_2$

  • 우희권;오은미;박종학;김보혜;김용남;윤찬호;함희숙
    • Bulletin of the Korean Chemical Society
    • /
    • 제21권3호
    • /
    • pp.291-294
    • /
    • 2000
  • The bulk photopolymerization of methyl methacrylate(MMA) with bis(silane)s such as 1,4-$C_6H_4(SiH_3)_2$ (1) and 1,4-$C_6H_4(SiH_2Me)_2$ (2) was performed to produce poly(MMA)s possessing the corresponding bis(silyl) moiety as an end group. For the bis(silane)s, while the polymerizaiton yields and the polymer molecular weights decreased, the TGA residue yields and the relative intensities of Si-H IR stretching bands increased as the relative bis(silane) concentration over MMA increased. The polymerizaion yield, polymer molecular weight, and TGA residue yield of MMA with 1 were found to be higher than those with 2. The bis(silane)s appears to influence significantly upon the photopolymerization of MMA as both chain initiation and chain transfer agents.

옥상녹화가 PV모듈 발전량에 미치는 영향 고찰 (A study on the effect that the green roof has on the performance of PV module)

  • 유동철;이응직
    • 한국태양에너지학회 논문집
    • /
    • 제32권2호
    • /
    • pp.113-119
    • /
    • 2012
  • This study aims to examine the effect of the combined application of green roof and PV system on the PV efficiency by measuring the temperature and performance of PV module in order to reduce the temperature on the roof using roof planting system and determine the potential of efficient increase in solar-light power generation. In the experimental methodology, either monocrystalline or polycrystalline PV module was installed in green roof or non-green roof, and then the surface temperature of PV was measured by TR-71U thermometer and again the performance, module body temperature, and conversion efficiency were measured by MP-160, TC selector MI-540, and PV selector MI-520, respectively. As a result, the average body temperature of monocrystalline module was lower by $6.5^{\circ}C$ in green roof than in non-green roof; that of polycrystalline module was lower by $8.8^{\circ}C$ in green roof than in non-green roof. In the difference of generation, the electricity generation of monocrystalline module in green roof was 46.13W, but that of polycrystalline module was 68.82 W, which indicated that the latter produced 22.69W more than the former.

Maslinic Acid, a Triterpenoid from the Root Barks of Ulmus davidiana var. japonica, Affects the Viability of HSC-T6 Hepatic Stellate Cells

  • Lee, Sang-Hoon;Liu, Qing;Kim, Seon-Beom;Ahn, Jong-Hoon;Ahn, Mi-Jeong;Hwang, Bang-Yeon;Lee, Mi-Kyeong
    • Natural Product Sciences
    • /
    • 제17권3호
    • /
    • pp.216-220
    • /
    • 2011
  • Activation of hepatic stellate cells (HSCs) characterized by increased proliferation and extracellular matrix deposition is identified as the major pathological feature of hepatic cirrhosis. Therefore, suppression of HSC activation has been proposed as an important antifibrotic therapeutic strategy. In the present study, we investigated the antiproliferative activity of root barks of Ulmus davidiana var. japonica (Ulmaceae) by employing HSC-T6 hepatic stellate cells as an in vitro assay system. Further investigation of the n-hexane and $CHCl_3$ fractions of root barks of U. davidiana var japonica led to the isolation of six triterpenoids: friedelin (1), epifridelanol (2), oleanolic acid (3), maslinic acid (4), ${\beta}$-amyrin (5) and ${\alpha}$-amyrin (6), together with ${\beta}$-sitosterol (7) and daucosterol (8). Among these compounds, 2, 3 and 4 significantly inhibited HSC proliferation. In addition, 4 inhibited HSC proliferation in time- and concentration-related manners, via a partially direct toxic effect, as assessed by morphological changes and release of lactate dehydrogenase.

(Polystyrene-divinylbenzene)-thiazolylazo phenol형 킬레이트 수지에 의한 금속이온의 분리 및 농축에 관한 연구(II) (Studies on the Separation and Preconcentration of Metal Ions by Chelating Resin containing (Polystyrene-divinylbenzene)-thiazolylazo phenol Derivatives(II))

  • 임재희;설경미;안혜숙;정구춘;이창헌;이원
    • 분석과학
    • /
    • 제9권4호
    • /
    • pp.364-372
    • /
    • 1996
  • 해수 중 U(VI) 등과 같은 미량 금속이온의 선택적인 분리, 농축 및 회수를 위하여 XAD-16-[2-(2-thiazolylazo)-p-cresol](TAC)형 킬레이트 수지에 대한 몇 가지 금속이온의 흡착 및 탈착 특성을 용리법으로 조사하였다. 금속이온의 흡착에 미치는 흐름속도, pH 및 완충 용액의 농도에 대한 영향을 조사하여 흡착 최적 조건을 결정하였다. 킬레이트 수지에 대한 금속이온의 총괄 흡착 용량을 조사한 결과 각각 0.41mmol U(VI)/g resin, 0.55mmol Th(IV)/g resin, 0.43mmol Cu(II)/g resin 및 0.32mmol Zr(IV) /g resin이었다. pH 5.0에서 돌파점 용량과 총괄 용량으로부터 얻은 금속이온의 용리 순서는 Th(IV)>Cu(II)>U(VI)>Zr(IV)>Pb(II)>Ni(II)>Zn(II)>Cd(II)>Mn(II)이었다. $HNO_3$, HCl, $HClO_4$, $H_2SO_4$$Na_2CO_3$ 등의 탈착제에 의한 탈착특성을 조사한 결과 Zr(IV)을 제외한 대부분의 금속이온들에 대하여 2M $HNO_3$이 탈착효율이 높게 나타났으며, 1M $H_2SO_4$ 용액을 사용하면 Zr(IV)의 탈착 및 회수가 가능하였다. 또한 킬레이트수지를 이용하여 미량의 U(VI) 이온이 함유된 인공 해수 시료를 용리시키고 회수한 결과 96% 이상의 높은 회수율을 나타내었다.

  • PDF

Plasminogen Activators Activities in Oviductal Epithelial Cells during Estrus Cycle in the Pig

  • Shin, Mi-Young;Kim, Tae-Shin;Kwon, Eun-Hye;Park, Soo-Bong;Park, Chun-Keun;Lee, Dong-Seok
    • Reproductive and Developmental Biology
    • /
    • 제32권2호
    • /
    • pp.89-95
    • /
    • 2008
  • The present study was undertaken to identify changes of plasminogen activators (PAs) in porcine oviductal epithelial cells (POECs) during the estrous cycle classified with post-ovulatory stages (Post-Ov), early to mid-luteal stages (Early-mid L) and pre-ovulatory (Pre-Ov) stages. The urokinase-type plasminogen activator (uPA) was only observed on day 5 and day 7 of culture in the POECs on all the estrous cycles and gradually increased according to increasing culture times, but not Early-mid L. In POECs-conditioned medium, uPA, tissue-type (tPA) and tPA-PA inhibitor (tPA-PAI) activity were observed at all culture times during estrous cycles. The uPA activity of POECs-conditioned medium on Post-Ov stage were significantly (p<0.05) decreased during prolonged cultures. On the other hand, the tPA activity of POECs-conditioned medium at Post-Ov stage was significantly (p<0.05) higher on day 5 than compared to the other days. Although was higher on day 1 at Post-Ov stage, the tPA-PAI activity of POECs-conditioned medium was significantly (p<0.05) higher on day 7 at all stage than that of day 5 of the culture. Taken together, these results suggest that uPA, tPA and tPA-PAI are produced by POECs, and the variations of the PAs activity are regulated in the different stages of the estrous cycle.

월경주기에 따른 우울지수 정도와 음성특성과의 상관관계 분석 (The Correlation of Voice Characteristics and Depression Index Analysis in Accordance with Menstrual Cycle)

  • 김유미;장승진;김은연;최예린
    • 말소리와 음성과학
    • /
    • 제6권3호
    • /
    • pp.41-48
    • /
    • 2014
  • This study investigated the differences between emotional parameters BDI, VHI, STAI-X-I and STAI-X-II according to the menstrual cycles of the female and the relation between changes of the depression index and voice characteristics (jitter, shimmer, CPP, HNR, $pF0{\cdot}F1{\cdot}F2{\cdot}F3$, sF0, sF4, sB1, $H1_{c/u}$, $A1_u$, $A3_c$, $H1A3_{c/u}$, $H1A1_u$). Twenty three females ($30{\pm}4.4$ years old) living in Seoul and Gyeonggi Province were participated in this study to answer the questionnaires and record their voice. The participants prolonged /a/ vowel for 5 seconds in a natural condition for their voice recording. Voice data were analyzed using the Matlab and Praat program. A t-test and a correlation analysis were conducted by using SPSS for the statistical analysis. The results are as follows. First, the BDI is significantly higher in group I (lurear phase contrast the menstrual period) and group II (follicular phase against the menstrual period) than group III (luteal phase for follicular phase) (p<.05). Second, shimmer, CPP, pF0 showed a statistically high correlation regarding the BDI in group I (lurear phase contrast the menstrual period). Voice parameters may be useful as supplement in evaluating the emotional change in the phase of menstrual cycle.

한국과 미국의 초등수학 서술형 평가의 제도 및 문항 비교 (A Comparative Analysis of System and Problems of Descriptive Assessment in Elementary School Mathematics Between Korea and U.S.A.)

  • 김민경;조미경;김래영;김구연;노선숙
    • 한국학교수학회논문집
    • /
    • 제15권2호
    • /
    • pp.239-258
    • /
    • 2012
  • 본 연구는 한국과 미국의 국가, 교육청, 학교 수준에서의 서술형 평가와 관련한 제도 및 문항에 관한 국제 비교를 함으로써 두 나라에서 서술형 평가가 실행되는 수준별 현황을 살펴보고, 서술형 평가의 효율적인 적용을 위한 시사점을 찾아보고자 한다. 비교 결과, 한국과 미국의 국가 수준의 교육과정에서는 공통적으로 문제해결 과정에 대한 평가와 교수 학습과정과 평가 간의 높은 연계성을 갖는 평가 방식의 중요성이 강조되고 있다. 그러나 교육청 수준에서 한국은 문서상에서 서술형 평가 실시 비율을 제시하는 데에 치중하는 경향이 짙은 반면, 미국의 각 주(State)에서는 교실 현장에서 실제적으로 활용할 수 있는 예시문항과 채점기준을 제시하여 활용을 도울 수 있도록 한 차이를 나타냈다.

  • PDF

갈화 약침이 알콜 중독 흰쥐의 치상회에서 신경세포 생성에 미치는 영향 (Effects of Puerariae flos herb-acupuncture on cell proliferation and neurogenesis in the dentate gyrus of ethanol-induced Sprague-Dawley rats)

  • 김연희;김이화;장미현;임백빈;김연정;정주호;서정철;김창주
    • Journal of Acupuncture Research
    • /
    • 제18권6호
    • /
    • pp.206-214
    • /
    • 2001
  • The purpose of this study was to determine the effects of Puerariae flos herb-acupuncture on hippocampal neural cell proliferation. Sprague-Dawley rats were randomly assigned into 4 groups; control group, control with herb-acupuncture group, alcohol group, alcohol with herb-acupuncture group group. Control groups were received with NaCl, while alcohol intoxication groups were injected intraperitoneally with alcohol (2 g/㎏) twice per day for 3 days. Herb-acupuncture groups were injected on Zhongwan (CV 12) for 5 consecutive days. Bromo-deoxyuridine (BrdU) was injected into all animal per day for 5 days. For the detection of BrdU-positive cells in dentate gyrus of hippocampus, immunohistochemistry was performed. In alcohol group, a significant decrease in BrdU-positive cells was observed compared to control group. In alcohol with herb-acupuncture group, BruU-positive cells increased significantly compared to alcohol group. In conclusion, the present results revealed that new cell proliferation is enhanced in the dentate gyros of young Sprague-Dawley rats through Puerariae flos herb-acpuncuture in an acute alcoholic intoxication condition.

  • PDF

생쥐 초기 2-세포 배에서 세포 내 칼슘 농도의 변화에 $Ni^{2+}$이 미치는 영향 (The effect of $Ni^{2+}$ on the intracellular $Ca^{2+}$ increase of the mouse early 2-cell embryos)

  • 윤숙영;이은미;배인하
    • Clinical and Experimental Reproductive Medicine
    • /
    • 제30권4호
    • /
    • pp.269-280
    • /
    • 2003
  • Objective: We reported the overcoming effect of $Ni^{2+}$ on the in vitro 2-cell block of mouse embryos. In this study, we aim to investigate whether $Ni^{2+}$ should induce intracellular $Ca^{2+}$ transient in the mouse embryos. Materials and Methods: Embryos were collected at post hCG 32hr from the oviduct of the ICR mouse and cultured in M2 medium omitted phenol red. Intracellular $Ca^{2+}$ was checked by using a confocal laser scanning microscope and fluo-3AM by using various intracellular $Ca^{2+}$ antagonists. Results: In 1mM $Ni^{2+}$ treated medium which contained $Ca^{2+}$(1.71mM), 75.7% of the embryos showed $[Ca^{2+}]i$ transient about 200 sec later. In the $Ca^{2+}$-free medium, 69.8% of the embryos showed $[Ca^{2+}]i$ transient. In U73122, phospholipaseC(PLC) inhibitor (5uM, 10min) pretreated group, 33.3% of the embryos showed $[Ca^{2+}]i$ transient. Heparine, inositol 1, 4, 5-triphosphate receptor(IP3R) antagonist preinjected embryos showed no response with 1mM $Ni^{2+}$. In danthrolene treatment, ryanodine receptor(RyR)-antagonist, 43% embryos showed $[Ca^{2+}]i$ transient but they showed delayed response about 340sec in the presence of $Ca^{2+}$. Conclusions: Summing up the above results, $Ni^{2+}$ seems to induce $Ca^{2+}$-release from the $Ca^{2+}$-store even in the $Ca^{2+}$-free medium. IP3 receptors of the mouse 2-cell embryos might have an essential role for the intracellular $Ca^{2+}$ increase by $Ni^{2+}$.

거주성 관점의 미국 이재민 임시대피시설 공간계획 관련 지침분석 (Analysis of the Space Planning Guidance about the Temporary Shelter Emphasizing Habitability for Disaster Victims in U.S.)

  • 김미경;최선미;최유라
    • 한국실내디자인학회논문집
    • /
    • 제26권5호
    • /
    • pp.42-51
    • /
    • 2017
  • The purpose of this study was to analyze the information about the disaster temporary shelter space planning guidance described in the U.S. shelter guidelines in terms of the habitability for disaster victims and to address the implications and potential impacts of its findings for the improvement of the shelter design standards and guidelines in Korea. The researchers reviewed four federal and non-governmental organization shelter field and design guidelines and attributes regarding the shelter space planning were classified in accordance with four habitability categories: Safety, Health, Convenience, and Comfort. Three major findings emerged from this study: 1)A total of 72 items about the shelter space planning were extracted from guidelines, and the majority of items are concerned with dormitory areas and sanitary spaces. Other items were about accessibility, children respite care area, signage, health service areas, food preparation and serving areas, parking and drop-off areas, registration and waiting areas, shelter manager and staff areas, lounge and storage areas, and household pets area. 2)Most of these items are strongly related to the convenience category(66.7%), followed by comfort(40.3%), safety(30.6%), and health(25.0%). 3)The habitability of the disaster temporary shelter can be established with considerations on the needs of disaster victims and vulnerable people, minimum occupancy space per person, separate sanitary spaces for the privacy, safe and convenient access routes to the shelter, and the provision of children areas for safety and comfort. The study findings will contribute to the development of the disaster shelter guidelines in Korea by suggesting shelter space planning indicators related to the habitability for the governmental and non-governmental organizations' immediate and systematic responses to the disaster.