• 제목/요약/키워드: Chemical products

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Mechanical Impact Treatment on Pulp fibers and Their Handsheet Properties

  • Yung B. Seo;Kim, Dukki;Lee, Jong-Hoon;Yang Jeon
    • 펄프종이기술
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    • 제34권5호
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    • pp.56-62
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    • 2002

  • Alternative way of shaping fibers suitable for papermaking was introduced. Impact refining, which was done simply by hitting wet fibers with a metal weight vertically, was intended to keep the fibers from shortening and to cause mostly internal fibrillation. Virgin chemical pulp, its recycled one and OCC were used in the experiment. It was noticed from the experiment that impact refining on virgin chemical pulp kept the fiber length and increased bonding properties greatly. However, in the recycled fibers from the chemical pulp, fiber length and bonding properties were decreased. In OCC, which seems to contain fractions of semi-chemical pulp and mechanical pulp (GP), and which is recycled pulp from corrugated boxes, fiber length and bonding properties were decreased disastrously. We believe recycled cellulosic fibers (recycled chemical pulp and OCC in this case), which went through hornification, were less resistant to the mechanical impact than virgin chemical pulp. For virgin chemical pulp, impact refining allowed no significant fiber length shortening, high WRV, and high mechanical strength.

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Palladium Dichloro Complex Catalysed Oxidation of Cyclopentene by Dioxygen in Tetralin$^\dag$

  • Takehira, Katsuomi;Hayakawa, Takashi;Orita, Hideo;Shimizu, Masao;Oh, In-Hwan
    • Bulletin of the Korean Chemical Society
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    • 제8권4호
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    • pp.254-257
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    • 1987

  • Palladium dichloro complexes catalysed the oxidation of cyclopentene by dioxygen in tetralin solvent at ambient temperature. Cyclopentanone formed mainly together with autoxidation products from both cyclopentene and tetralin. The oxidation seems to proceed by co-oxidation mechanism, where tetralin was first oxidized to its hydroperoxide which then oxidized cyclopentene to cyclopentanone. Mechanism of the other by-products formations has been discussed.

  • https://doi.org/10.5012/bkcs.1987.8.4.254 인용 PDF

A New Oxygenated Furano Sesquiterpene from the Sponge Dysidea fragilis

  • Venkateswarlu, Y.;Reddy, N. Srinivasa;Ramesh, P.
    • Natural Product Sciences
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    • 제4권3호
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    • pp.158-160
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    • 1998

  • A new oxygenated furano sesquiterpene [1] has been isolated from the sponge Dysidea fragilis collected from Mandapam coast, Tamilnadu, India and its structure was determined by analysis of spectral data.

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