• 제목/요약/키워드: Cactus

검색결과 167건 처리시간 0.026초

합성섬유 및 바이오 폴리머를 혼입한 3D 프린팅 모르타르의 재료특성 (Material Properties of 3D Printed Mortars Produced with Synthetic Fibers and Biopolymers)

  • 김효정;이병재;김윤용
    • 한국구조물진단유지관리공학회 논문집
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    • 제27권4호
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    • pp.78-85
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    • 2023
  • 3D 프링팅 출력물에서 발생할 수 있는 수축 균열을 저감하기 위해 합성섬유를 보강하고, 선인장의 줄기(cactus stem, CS)를 활용한 바이오 폴리머 혼화제를 혼입하여 제조한 3D 프린팅용 모르타르의 재료특성을 평가하였다. 셀룰로우즈계 혼화제 (methylcellulose, MC)의 대체재로 CS 10% 일부 치환할 경우, 타설방법과 상관없이 9.84~23.92% 압축강도가 증가하는 것으로 나타났다. 또한, 타설방법과 상관없이 Plain 대비 수축변화, 동결융해, 균열 저항성이 개선됨을 나타냈다. 이는 CS를 일부 치환함으로써 다당류 폴리머 구조가 증가되어 내구성이 개선되는 것으로 판단된다. 섬유 배합의 경우, 섬유의 종류 및 혼입량이 압축강도와 동결융해에 영향을 미치지 않는 것으로 확인되었다. 섬유 혼입에 의해 수축변화와 균열 저항성에 효과적인 것으로 나타났다. 종합적인 결과, 3D 프린팅 모르타르 배합시 MC 대신 CS 10% 일부 치환하고 섬유를 보강할 경우 섬유 종류 및 혼입량과 상관없이 내구성, 균열 저항성에 효과적인 것으로 나타났다.

온실의 깍지벌레과(노린재목)에 대한 발생조사 (Notes on Armored Scale Species from Greenhouse in Korea (Hemiptera: Diaspididae))

  • 서수정;이성진
    • 한국응용곤충학회지
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    • 제48권3호
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    • pp.281-284
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    • 2009
  • 우리나라에 1920년대 후반부터 현재까지 72종의 깍지벌레과가 보고되었으며, 이중 9종은 온실에서 보고된 종이다. 온실에서 보고된 9종중 7종은 야외에서 서식하는 자생식물 또는 온실에서 재배되는 식물에서 발생이 확인되지 않았다. 나머지 2종은 온실에서 재배되고 있는 파인애플, 틸란드시아 및 선인장에서 채집 확인되었으나, 야외에서 서식하는 자생식물에서 발생되지 않았다.

화물유 펌프실의 환기특성에 관한 연구 (A Study on Ventilation Characteristics of Cargo-oil pump room)

  • 박찬수;조대환
    • Journal of Advanced Marine Engineering and Technology
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    • 제24권1호
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    • pp.134-141
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    • 2000
  • In this study, a scaled model chamber was built to investigate ventilation characteristics of the Under floor Air-conditioning System. Experimental study was performed in model for cargo-oil pump room with inlet and outlet by visualization equipment with laser apparatus. Instant simultaneous velocity vectors at whole field were measured by 2-D PIV system(CACTUS'2000) which adopted two-frame grey-level cross correlation algorithm. The flow pattern reveals the large scale counterclockwise forced-vortex rotation from upside louver to lower scupper toward diagonal corner and also found small eddies at bottom layer

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PIV 계측에 의한 $180^{\circ}$곡관 출구에 연결된 직관에서 층류정상유동의 운동에너지 (Kinetic energy of Laminar Steady flows in the Exit Reguon Connected to the straight Square-sectionnal $180^{\circ}$ curved Duct by using PIV)

  • 이종구;이홍구;손현철;이행남;박길문
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2002년도 학술대회지
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    • pp.521-524
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    • 2002
  • In the present study, kinetic energy of laminar steady flow in the exit region connected to the square-sectional $180^{\circ}$curved duct was investigated experimentally. The experimental study for air flows was conducted to measure kinetic energy distributions by using the Particle Image Velocimetry(PIV) system with the data acquisition and processing system of Cactus 2000 software. The results obtained from experimental studies are summarized as follows : (1) The critical Reynolds number for a change from laminar steady flow to transitional steadt flow was about 1910, in the 50 region of dimensionless axial position (x/Dh) whirh was considered as a fully developed flow region. (2) Maximum kinetic energy of laminar steady flow was gradually increased as the Reynolds number increased.

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손바닥선인장 열매 및 줄기 추출물의 생리활성(III)-흰쥐의 알코올성 고지혈증에 미치는 영향 (Biological Activities of the Extracts from Fruit and Stem of Prickly Pear(Opuntia ficus-indica var. saboten) III. - Effects on Subacute Alcoholic Hyperlipidemia in Rats)

  • 이정규;문영인;박희준;한용남;최종원
    • 생약학회지
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    • 제33권3호통권130호
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    • pp.238-244
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    • 2002
  • The extracts from stem and fruit of Cactus (Opuntia ficus-indica var. saboten Makino) were applied to confirm the antiatherosclerotic effects in subacute alcoholic hyperlipidemic rats. It was observed that several indications of hyperlipidemia were prevented or changed by the treatments of the extracts but activities of hepatic HMG-CoA reductase and alcohol dehydrogenase were not affected, which suggest that the extracts may promote the fecal excretion and delay the absorption of alcohol in hyperlipidemic rats.

Monoamine Oxidase B Inhibitors from the Fruits of Opuntia ficus-indica var. saboten

  • Han, Yong-Nam;Choo, Yeun-Su;Lee, Young-Chul;Moon, Young-In;Kim, Sung-Dae;Choi, Jong-Won
    • Archives of Pharmacal Research
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    • 제24권1호
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    • pp.51-54
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    • 2001
  • Three varieties of methyl citrate and 1 -methyl malate were isolated from the fruits of Opuntia ficus-indica var. saboten Makino through in vitro bioassay-guided isolation for the inhibition on monoamine oxidase(MAO). The $IC_50$ values for MAO-B of 1-monomethyl citrate, 1,3-dimethy citrate, trimethyl citrate and 1-methyl malate were 0.19, 0.23, 0.61 and 0.25 mM, respectively. However, on MAO-A, their inhibitions showed only marginal activity.

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상부채널을 갖는 사각공간에서 열유속 변화에 따른 공기대류의 속도와 온도 가시화 (Velocity and temperature Visualization of Air Convection in Differently Heated Rectangular Cavity with Upper channel)

  • 이철재;정한식;박찬수;조대환
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 춘계학술대회논문집B
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    • pp.290-295
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    • 2000
  • An experimental study was carried out in a cavity with upper channel and square heat surface by visualization equipment with Mach-Zehnder interferometer and laser apparatus. The visualization system consists of 2-dimensional sheet light by Argon-Ion Laser with cylindrical lens and flow picture recording system. Instant simultaneous velocity vectors at whole field were measured by 2-D PIV system(CACTUS'2000). Obtained result showed various flow patterns. Severe unsteady flow fluctuation within the cavity are remarkable and sheared mixing layer phenomena are also found at the region where inlet flow is collided with the counter-clockwise rotating main primary vortex. Photographs of Mach-Zehnder are also compared in terms of constant heat flux.

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Isolation of a Pestalotiopsis Species Degrading Mucilage from Fruit of Opuntia ficus-indica var. Saboten

  • Huh, Yoon-Hee;Ko, Young-Hwan
    • Journal of Applied Biological Chemistry
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    • 제50권4호
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    • pp.221-226
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    • 2007
  • The high molecular-weight mucilage extracted and purified from cactus fruit of Opuntia ficus-indica var. Saboten was degraded by the cell-free culture filtrate of a fungus isolated from soil. TLC analysis of the polymeric mucilage after incubation with the fungal culture filtrate confirmed its degradation. When the degradation products were tested for their qualitative reactions with ninhydrin and phenol-sulfuric acid, only phenol-sulfuric acid gave positive development, and ninhydrin did not show any observable color reaction. This coloring reaction suggested the presence of a carbohydrate without an amino group within the mucilage. Analyses by HPLC and liquid gel permeation chromatography on sephadex G-100 also provided additional information on degradation of the mucilage by the fungal culture filtrate. The sequences of ITS-5.8S rDNA from the fungal isolate that was cultivated for the preparation of mucilage-degrading enzyme showed 99% similarity to those of Pestalotiopsis aquatica.

상부채널을 갖는 사각공간에서 열유속 변화에 따른 공기대류의 속도와 온도 가시화 (Velocity and Temperature Visualization of Air Convection in Differently Heated Rectangular Cavity with Upper Channel)

  • 이철재
    • 태양에너지
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    • 제20권4호
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    • pp.53-60
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    • 2000
  • An experimental study was carried out in a cavity with upper channel and square heat surface by visualization equipment with Mach-Zehnder interferometer and laser apparatus. The visualization system consists of 2-dimensional sheet light by Argon-Ion Laser with cylindrical lens and flow picture recording system. Instant simultaneous velocity vectors at whole field were measured by 2-D PIV system(CACTUS'2000). Obtained result showed various flow patterns. Severe unsteady flow fluctuation within the cavity are remarkable and sheared mixing layer phenomena are also found at the region where inlet flow is collided with the counter-clockwise rotating main primary vortex. Photographs of Mach-Zehnder are also compared in terms of constant heat flux.

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Functional bioactivity of Opuntia species

  • Shin, Tae-Kyun;Wie, Myung-Bok;Lee, Nam-Ho;Lee, Du-Sik;Son, Won-Geun;Park, Dal-Soo;Ahn, Mee-Jung;Go, Gyung-Min
    • Advances in Traditional Medicine
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    • 제4권4호
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    • pp.219-226
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    • 2004
  • Cacti of the genus Opuntia, which are widely distributed throughout Latin America, South Africa, the Mediterranean, and Korea, have been used not only as ornamental plants but also for their medicinal value. For example, Opuntia spp. have traditionally been used as hypoglycemic plants for treating diabetes mellitus. In this article, we review published papers dealing with the biological and medicinal properties of Opuntia spp.