• Title/Summary/Keyword: Chemical pulp

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Detection of Endosulfan from Oral Tissues of Acute Poisoned Rabbits (급성중독 가토의 치아 및 악골조직에서의 Endosulfan 검출에 관한 실험적 연구)

  • 조호현;김종열
    • Journal of Oral Medicine and Pain
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    • v.9 no.1
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    • pp.147-156
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    • 1984
  • In spite of the radical increase of chemical poisoning cases caused by prevalent of oranic chlorine like endosulfan, the study of detection of chemical poisoning has seldom been attempted; the study of poisoning in teeth, which is more secure physiochemically, and in all the oral tissues has been even less attempted. The author has administered endosulfan into the month of a rabbit, causing its death, and tried to detect endosulfan in the teeth, jaws, and oral tissues through forensic chemical and histopathological tests. The result obtained is as follows : 1. By thin layer chromatography, endosulfan was detected in the jews, dental hard tissues, dental pulp, blood, and the liver. 2. By gas chromatography, it was also detected in the jaws, dental hard tissues, dental pulp, blood, and the liver. 3. The congestion and hemorrhage in buccal mucosa, palatal mucosa, and dental pulp was detected.

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Studies on the production of Various Chemical Pulps from Bamboo (대나무를 이용한 각종 화학펄프 제조에 관한 연구)

  • 강진하;박성종
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.32 no.3
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    • pp.57-64
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    • 2000
  • This study was carried out to acquire basic data necessary for the use of non-wood pulp. It investigated various chemical pulping methods using bamboo to achieve higher yield lower kappa no. and then the physical properties of various pulps were tested. The results of this study were as follows. When various chemical pulps(Soda, Soda-AQ, Soda-AQ-H2O2, Soda-urea, AS, AS-AQ, Kraft) were produced with bamboo. the pulps with the higher yield and lower kappa no. were AS-AQ and Kraft. In the case of the breaking length Soda pulps(5.77∼6.46 km) showed the greatest and Soda-urea pulps(3.81∼4.522km) showed the lower value. Similarly for the burst index Soda pulps (3.28∼3.50 kPa$.$m2/g) were the best and Soda-urea pulps(2.29∼2.39 kPa$.$m2/g) were worst. On the other hand the tearing indexes of AS-AQ pulps(73.6∼89.7mN$.$m2/g) showed the tendency which was higher then those of other pulps.

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Catalytic Decomposition of Hydrogen Peroxide by Transition Metal Ions (금속 이온에 의한 과산화수소의 촉매분해)

  • Kim, Se-Jong;Yoon, Byung-Ho
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.38 no.3 s.116
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    • pp.79-84
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    • 2006
  • Hydrogen peroxide has been a bleaching chemical for varied pulp, especially mechanical and deinking pulp. It is catalytically decomposed by some transition metals in pulp slurry. In this paper, some metals which can be contained in pulp such as manganese, copper, iron, magnesium and calcium were used to investigate their effect on the decomposition of hydrogen peroxide. From the result, hydrogen peroxide was more decomposed in the order of Mn, Cu, $Fe^{3+}\;and\;Fe^{2+}$, while Mg and Ca had little effect on the decomposition of hydrogen peroxide. The effect of Mg/Mn ratio on the decomposition of hydrogen peroxide was also investigated. At the specific ratio of them(Mg/Mn=10), hindering effect of peroxide decomposition by Mg was decreased.

Application of WCT (Wet Compaction Test) to Mixed Fiber Furnishes (Wet compaction test를 이용한 혼합지료의 적용)

  • Seo Yung B.;Lee Chun Han
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.37 no.4 s.112
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    • pp.8-17
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    • 2005
  • WCT (Wet compaction test) is a new fiber evaluation method developed recently by Seo and its test results can be used as a predictor for pulp quality and its paper property Bleached chemical pulps (SwBKP, HwBKP), recycled pulp (OCC), and mechanical pulp (BCTMP) were used for the furnishes to be tested by WCT We compared the WCT results to conventional fiber evaluation tests such as WRV (Water Retention Value), free ness, and fiber length in this study, and found that WCT always gave better regression coefficients in relation to pulp quality (drainage), and paper properties (density, tensile, tear, and burst strength). WCT may be used on-line in papermachine.

Development of Pulping Methods of Rice-straw Chemical Pulp with Higher Yield and Lower Kappa Number (고수율 및 저카파가의 볏짚화학펄프 제조방법 개발)

  • 강진하;박성종
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.32 no.2
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    • pp.58-67
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    • 2000
  • This study was carried out to acquire basic data necessary for the use of non-wood pulp. Various chemical pulping methods for rice straw to achieve higher yield, lower Kappa No. were investigated and then the physical properties of various pulps were tested. The results of this study were as follows: When various chemical pulps (Soda, Soda-AQ, Soda-$H_2O_2$, Soda-$Na_2S_2$, AS, AS-AQ, AS-$Na_2S_2O_3$, AS-$Na_2S_2O_4$, Kraft) were produced with rice-straw, the pulps with the highest yield and lowest Kappa No. were obtained with Soda-$Na_2S_2$and AS-$Na_2S_2O_4$pulps. For the breaking length, Soda and Soda-additive pulps(7.5~9.2km) were better than AS and AS-additive pulps(6.2~8.1km). Similarly, for the burst index, Soda and Soda-additive pulps(6.0~7.0 kPa.$m^2$/g) were better than AS and AS-additive pulps(4.5~6.3 kPa.m$^2$/g). But the tear index was showed 21.8-30.9 mN.$m^2$/g with a little different between pulping methods.

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Soda-Anthraquinone Pulping and Alkaline Sulfite-Anthraquinone Pulping of Rice-Straw (볏짚을 이용한 소다-안트라퀴논 펄프 및 알칼리성 아황산염-안트라퀴논 펄프 제조)

  • 강진하;박성철;박성종
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.29 no.3
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    • pp.34-42
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    • 1997
  • This study was carried out to investigate the proper cooking conditions of soda-anthraquinone and alkaline sulfite-anthraquinone pulping of rice-straw, and get basic data f9r the use of rice-straw chemical pulp through the test of characteristics and physical properties of pulps made in the various cooking conditions From the experimental results , we can conclude as follows. In the soda-anthraquinone pulping of rice-straw, the optimum cooking conditions were 60 min. at $150^{\circ}C$ in the amount of caustic soda of 20% with the addition of anthraquinone(0.05%). And total yield, Kappa No. and brightness of pulp made in the condition above mentioned were 41.9%, 7.7 and 51.1 respectively. In the alkaline sulfite-anthraquinone pulping of rice-straw, the proper mixing ratio of cooking chemical(caustic soda : sodium sulfite) was 50:50. And the optimum cooking conditions were 60 min. at $150^{\circ}C$ in the amount of cooking chemical of 20% with the addition of anthraquinone(0.05%). At that time, the total yield, Kappa No, and brightness of pulp were 50.1%, 9.1 and 40.2 respectively. As a result, the alkaline sulfite-anthraquinone pulping was superior to the soda-anthraquinone pulping in the aspect of yield, but inferior in the viewpoints of Kappa No. and brightness. For the comparison of qualities of pulps made in the various cooking methods and conditions, the physical properties of four sorts of pulps were tested. As a result, soda-anthraquinone pulps were superior to alkaline sulfite-anthraquinone pulps in the various strengths excluding tear strength and brightness. On the other hand, pulps made in the condition of addition of cooking chemical of 20% were superior to pulps in the dosage of 15% in the aspects of all the strengths and brightness.

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