• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.337-347
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• 2006

Papers made from unbleached and bleached bagasse chemimechanical pulp were chemically modified by acetylation. The effects of irradiation on unbleached and bleached also reduced papers of bagasse chemimechanical pulp before and after acetylation were investigated in this study. Chemimechanical pulp was prepared from bagasse and then bleached with hydrogen peroxide. Unbleached and hydrogen bleached pulps were reduced by Sodium borohydride in different procedures. Paper sheets were prepared from pulps and then acetylated using a technical grade of acetic anhydride. Accelerated photo-aging was run on the samples using fluorescent lamps to verify photo-stability of paper sheets before and after pretreatments. Brightness reversion (as Post-color number) and other optical properties of the paper sheets were measured. Efficient inhibition of photo-yellowing of papers made from bagasse CMP was achieved by acetylation. The acetylated unbleached CMP was noticeably photo-bleached during irradiation. Sodium borohydride reduction followed by acetylation had the same effect as acetylation alone at the same degree of reaction time and reductive treatment did not affect the yellowing rate to any great extent. The pre-reduced, acetylated unbleached papers were, however, not brightened during irradiation. Calculation done by Kubelka-Munk equation showed that reductive treatment had little effect in reducing the photo-yellowing of paper made from CMP pulp; a small stabilization effect was observed in the case of bleached CMP, while unbleached CMP was slightly more prone to discolor in the later phase of photo-reversion. The improved stability towards light may was closely related to the decrease in the phenolic hydroxyl content as a result of blocking by acetyl groups during treatment with acetic anhydride. The results support the hypothesis that phenolic hydroxyl has an important role in the process of photo-reversion of high-yield pulps. The results obtained in this study demonstrate that the acetylation of paper manufactured from peroxide bleached Bagasse CMP significantly retards light-induced discoloration. The inhibition of yellowing is connected with a decrease in the phenolic hydroxyl content of both unbleached and peroxide bleached papers.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.365-372
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• 2006

In this paper, the possibility of statistical modeling from the pulp and peroxide bleaching condition variables to predict optical properties of a bleached chemimechanical pulp used in a newsprint paper machine at Mazandaran Wood and Paper Industries Company (MWPI) was studied. Due to the variations in the opacity and the brightness of the bleached pulp at MWPI and to tackle this problem, it was decided to study the possibility of modeling the bleaching process. To achieve this purpose, Multi-variate Regression Analysis was used for model building and it was found that there is a relationship between independent variables and pulp brightness as well as pulp opacity, consequently, two models were constructed. Then, model validation was carried out using new data set in the bleaching plant at MWPI to test model predictive ability and its performance.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.04b
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• pp.394-397
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• 1999

The relation between the paper formation analyzer by image process system and smoothness, compressibility uniform of ink absorption is studied. There results indicate that the paper with bad formation has higher apparent bulk than the paper with good formation. The bad formation of paper results in the nonuniform calendering and decrease of the compressibility. The bad formation of paper also results in deformation and omission of printing dots, which affects the reproduction of the printing images.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.29 no.2
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• pp.25-35
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• 1997

오늘날 열대림 면적의 급격한 감소, 지구온난화등 지구환경 보전의 관점에서 이들 목재이외의 자원의 활용 및 양마와 같은 새로운 비목재자원 개발의 중요성이 재인식되기에 이르렀으며, 이 가운데서 양마는 생장이 라르고 수확량이 크며, 목질부의 단섬유는 물론 긴 섬유장을 가진 인피부섬유로 구성되어 있고, 실리카함량도 매우 적어, 특히 산림자원이 부족한 개발도상국에서 펄프.제지용 자원으로서 주목되고 있다. 양마가펄프.제지용자원으로서 오늘날과 같은 세계적 주목을 받게 된 것은 미국 농무성 북부지역연구센타 에서 이루어진 “새로운 섬유작물”에 관한 기초연구에서 양마가 제지용 섬유작물로서 높이 평가되고 있다. 양마의 경우 인피부는 비교적 리그닌함량이 적고, 목질부는 활엽수재에 가까운 리그닌을 함유하고 있는데다, 섬유형태에 있어서도 인피부와 목질부간에 큰 차이가 발견된다. 본 연구에서는 양마를 중성아황산법으로 전처리하여 제조한 반화학펄프로 부터 제조한 종이의 광학적 성질을 검토하였다 펄프의 광학적 성질은 원료의 화학적 조성,섬유의 형태, 부위.화학적 처리정도, 원료의 저장기간 및 충전제의 첨가에 따라 크게 영향을 받았다. 장섬유와 낮은 리그닌함량을 가진 전간부 펄프시트는 불투명도가 낮았으며, 목질부 펄프로부터 상대적으로 밀도가 다소 높고, 불투명도도 높은 종이를 만들 수 있었다. 펄프원료의 저장기간이 백색도를 낮추었으며, 불투명도에는 그다지 영향하지 않았다. 약품전처리 및 표백이 백색도 및 불투명도에 크게 영향하였고, 특히 충전제 첨가로 광산란을 증가시켜 불투명도가 높은 종이를 제조할 수 있었다.6. CL종의 난황콜레스테롤 수준에 대한 계란의 일령 상호간에는 전체적으로 상호간에 차이가 없었다. 7. 26주령시 혈중콜레스테롤 수준은 CL종이 다른 두 육계종들 보다 유의적 (P$\leq$0.05)으로 높았다. 8. 성별간 혈중콜레스테롤 수준의 차이는 CL종, BR1 및 BR2 중에서 CL종에서만 나타났으며, 수컷은 암킷보다 혈액 100 mL당 약 90 mg이 낮았다.구체적인 생화학적인 연구가 이루어져야 될 것으로 여겨진다.야 할 것으로 사료된다. 냉장 저장을 하고 저장기간이 길어질 경우는 냉동저장을 사용하는 것이 바람직하다고 생각된다.S, FOS나 말티톨로 대체된 스폰지 케익은 설탕 100% 사용한 케익과 비교하여 크게 나쁘지 않거나 휠씬 나은 특성을 보이므로 스폰지 케익 제조에 그들의 이용이 가능함을 확인하였다.thione 같은 다른 항산화제의 절약 효과, CYP2El의 유도 저하를 통하는 것으로 생각되며 그중 어떤 것에 가장 큰 영향을 받는 지는 아직 알려지지 않았고 더욱 많은 연구가 요구된다.우와 사료에 $\omega$3계 지방산 급원을 첨가, 동물에게 이행시켜 $\omega$3계 지방산 강화식품을 제조하는 두 가지 방법이 있을 수 있는데 전자는 통조림, 과자, 건강보조식품류에 다용되며 후자는 다양한 기능성 축산식품에 활용되고 있다. $\omega$3계 지방산 강화 축산식품에는 돼지고기, 우유, 치이즈, 계란, 분유, 햄 등 다양한 제품에 활용, 개발되고 있으며 최근에는 이러한 식품 개발에 더욱 박차가