• Title/Summary/Keyword: EUGENE

Search Result 292, Processing Time 0.034 seconds

The Quality of Crushed Sand by Dry Production Process and Its Influence on Properties of Concrete (건식공정으로 생산한 부순 모래의 품질 및 콘크리트 특성에 미치는 영향)

  • Park, Cho-Bum;Baek, Chul-Woo;Kim, Ho-Su;Ryu, Deuk-Hyun
    • Journal of the Korea Concrete Institute
    • /
    • v.18 no.3 s.93
    • /
    • pp.415-423
    • /
    • 2006

  • As the shortage of natural & good quality aggregate for concrete, it is needed development of alternative aggregate. At the present time, the crushed sand is widely used among the alternation aggregate, and the usage of crushed sand will be increased more and more. Generally, crushed sud is produced with wet process in domestic, but some manufacturing companies which are handicapped with local restrict are produced by dry process. In this study, analyzing the facilities of dry crushed sand, the quality properties of dry crushed sand was done by Korean Industrial Standards. Based on the quality results of dry crushed sand, the experiment of concrete with the dry crushed sand which is substitute for sea sand was done. As the results of basic qualities, the amount of 0.08 mm sieve passing ratio was over KS criteria, and the fineness modulus was higher than sea sand, and the other physical properties of dry crushed sand was similar to sea sand. The results of concrete experiment, according to the substitutive ratio of dry crushed sand is increased, the slump and air content of concrete was decreased by increase of fine particles of dry crushed sand, and the unit weight content, compressive & tensile strength of concrete were increased on the contrary. The physical properties of concrete used dry crushed sand were showed same tendency without relation to W/B. Consequently, if the fine particle contents of dry crushed sand was lower, it is judged that dry crushed sand is no problem to use for concrete aggregate and the amount of usage will be increased.

  • https://doi.org/10.4334/JKCI.2006.18.3.415 인용 PDF KSCI

The challenge of hapatitis B virus

  • Samanta, Hinadri K.
    • The Microorganisms and Industry
    • /
    • v.13 no.3
    • /
    • pp.3-11
    • /
    • 1987

  • Hepatitis B virus (HBV) is a very serious threat to public health in most of the developing countries of the world. It is estimated that around 300 million people worldwide are chronic carriers of this virus and will transmit the disease both vertically and horizontally. Infection by this virus may cause a wide range of clinical manifestations ranging from an asymptomatic infection to liver cirrhosis.

  • PDF

Effect of Maca Supplementation on Scopolamine-Induced Memory Impairment of Mice (마카(Lepidium meyenii) 보충이 생쥐에서 Scopolamine으로 손상된 기억력 회복에 미치는 효과)

  • Lee, Hong-Mie;Park, Eun-Jin;Jeon, In-Sook;Kang, Yong-Soo;Jin, Dong-Il;Chung, Hai-Jung
    • The Korean Journal of Food And Nutrition
    • /
    • v.23 no.4
    • /
    • pp.485-491
    • /
    • 2010

  • With an increase in the number of people suffering from ageing-related diseases in our rapidly aging society, interests in natural products such as maca(Lepidium meyenii), which has properties of enhancing cognition and sexual performance, have increased. This study was conducted to assess the effects of 7 weeks of maca extract supplementation(0.5~2.0 g/kg BW) on scopolamine-induced amnesia in mice and on sperm count in male mice. All doses of maca supplementation significantly protected against scopolamine-induced amnesia as determined by a Morris water maze, but not according to passive avoidance tests. Maca supplementation did not affect acetylcholinesterase activity in the whole brain, nor the testicular sperm count of male mice. This study suggests that maca may have some neuroprotective properties in mice, which will be further examined by future studies.

  • PDF KSCI