• Journal of Biosystems Engineering
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• 제43권4호
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• pp.362-368
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• 2018

Purpose: Self-sufficiency in paper production is desired in Nigeria. This study was aimed at evaluating the performance of a locally fabricated batch pulp digester. Methods: The pulp yields of sheaths generated as waste in the production of bamboo (Bambusa vulgaris) laminates were determined at different liquor concentrations and treatment time after preliminary experiments to ascertain the conditions under which the sheath started to pulp. Moreover, the optimum pulping conditions and fiber characteristics were determined and estimated, respectively, to ascertain the pulp fiber suitability for paper production. Results: An optimum pulp yield of 65.1% was obtained at 50% NaOH and 25% $Na_2S$ liquor concentration (w/w) when the cooking time was 4 h. The results of fiber characterization of the pulp indicated an average fiber length of 2.19 mm with a low Runkel ratio of 1.63, both of which signify the suitability of the pulp for medium quality paper production. Conclusions: Softwood pulp can be blended with the fibers to improve the strength of the produced paper; further investigation should be carried out to use other non-woody plants for pulp and papermaking.

• 한국초지조사료학회지
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• 제16권1호
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• pp.75-80
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• 1996

The corn is one of the most important forage crop in Korea. The harvest time for silage affects dry matter (DM) yield and silage quality. This study was carried out to determine the effect of harvest time on the DM yield and nutritive value of corn forage at the Experimental Livestock Farm, College of Agriculture and Life Sciences, Seoul National University, Suweon in 1991. Forage DM yield and DM content of corn forage significantly increased mainly due to increase of ear. And also the ear to total DM ratio increased from 30% to 55% as the harvest was delayed. Chemical composition of the corn forage was improved by reduction in crude fihr, neutral detergent fiber and acid detergent fiber as the harvest was delayed. This results indicated that the harvest time of corn forage plays an important role to determine DM yield and DM contents for silage materials.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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• pp.727-732
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• 1999

In this research, we made an experiment on the 10 specimen beams that we made. The specimen beams consist of 4 steel plate strengthening beams and 5 carbon fiber sheet strengthening beams. We applied the methods of notch, rounding off a edge, anchor bolt and side shear strengening to the steel plate and for the case of carbon fiber sheet, we applied the methods of anchor bolt, line anchor and shear strengthening. After all the cases were applied, the beams was measured and analyzed about the behavior property of strengthened beams, th ability of strengthening method, the relation between load and the shape of failure, the crack load, the yield load, the shape of crack pattern, the increasing rate from yield load and maximum load and the strain of rebar. All the strengthening methods resulted in almost same value until the yield load, and it wasn't quite different from the theoretical value. In comparison with existing method, the SER, SEAS for the steel plate and the CEA, CESS, CCESS for carbon fiber sheet showed the increasement of ductility with big displacement.

• 한국건설순환자원학회논문집
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• 제2권3호
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• pp.188-195
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• 2014

방호 방폭용 뿜칠형 고성능 섬유보강 시멘트 복합재료(HPFRCC) 개발을 위한 기초적인 연구의 일환으로 페이스트, 모르타르 및 HPFRCC 각 단계에서 구성재료의 레올로지 특성을 평가하였다. 페이스트 단계에서 레올로지 실험결과, GGBFs 및 FA의 경우 혼합률 증가에 따라 소섬정도 및 항복응력은 감소되는 것으로 나타났으며, SF의 경우 혼합률 10% 이후부터 소성점도 및 항복응력이 급격하게 증가되는 것으로 나타났다. 모르타르 단계에서 레올로지 실험결과, 잔골재의 종류 즉, 잔골재의 입형 및 입도는 소성점도 및 항복응력에 많은 영향을 미치는 것으로 나타났으며, Vs/Vm의 변화는 항복응력 보다 소성점도에 더 큰 영향을 미치는 것으로 나타났다. HPFRCC 단계에서 유동성 및 레올로지의 실험결과, 섬유 혼입 후 유동성 및 섬유분산성 개선에는 SP 보다 VA가 더 유효한 것으로 나타났다.

• 한국작물학회지
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• 제41권2호
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• pp.230-235
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• 1996

재식밀도가 대류의 자웅성의 발현과 섬유수량에 미치는 영향을 구명코자 1995년 3월부터 1995년 8월 까지 호남농업시험장 목포시험장 특작포장에서 시험한 결과를 요약하면 다음과 같다. 1. 경장은 재식밀도 60$\times$20cm(8,333주/10a)의 소식에서 가장 길었고, 경태는 재식밀도 40$\times$20cm:12,500주/10a)에서 가장 굵었다. 2. 피마율은 재식밀도 40$\times$5cm(50,000주/10a)의 최다 밀식구에서 가장 높았고, 섬유수량 역시 가장 높았다. 3. 자웅성비의 변화는 40$\times$5cm(50,000주/10a)에서 자성의 비율이 가장 높아서 밀식으로 인한 자성의 비율을 높이는 효과를 거둘 수 있었다.

• 한국초지조사료학회지
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• 제8권2호
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• pp.128-134
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• 1988

This experiment was carried out to compare chemical composition of corn-cowpea inter cropping and corn monocropping plants at different harvestion time and obtained the following results. 1. In both cropping systems, the contents of crude fat and nitrogen free extract (NFE) were significantly increased (P<0.01), while that of crude protein crude fiber and crude ash were decreased (P<0.01) with each harvesting time. 2. The acid detergent fiber (ADF) and crude fiber contents were decreased same patterns in growing period, however, according to maturing of corn ears the difference between ADF and crude fiber contents reduced. 3. At mature stage, crude protein yields per 10a in corn monocropping and corn-cowpea intercropping system were 127.6kg and 152.1kg, respectively. The difference of crude protein content between corn-cowpea intercropping and corn monocropping system was 19.2%. 4. TDN yields of each cropping system, at mature stage, obtained similar results and TDN yields per 10a of corn monocropping and corn-cowpea intercropping system were 1006.1kg and 990.1, respectively. 5. Conseqently, corn-cowpea intercropping system could be increased protein yield without decreasing of dry matter yield in comparison with corn monocropping system.

• 한국초지조사료학회지
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• 제8권3호
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• pp.128-134
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• 1988

This experiment was carried out to compare chemical composition of corn-cowpea intercropping and corn monocropping plants at different harvesting time and obtained the following results. 1. In both cropping systems, the contents of crude fat and nitrogen free extract (NFE) were significantly increased (P<0.01), while that of crude protein, crude fiber and crude ash were decreased (P<0.01) with each harvesting time. 2. The acid detergent fiber (ADF) and crude fiber contents were decreased same patterns in growing period, however, according to maturing of corn ears the difference between ADF and crude fiber contents reduced. 3. At mature stage, crude protein yields per 10a in corn monocropping and corn-cowpea intercropping system were 127.6kg and 152.lkg, respectively. The difference of crude protein content between corn-cowpea intercropping and corn monocropping system was 19.2%. 4. TDN yields of each cropping system, at mature stage, obtained similar results and TDN yields per 10a of corn monocropping and corn-cowpea intercropping system were 1006.lkg and 990.1, respectively. 5. Conseqently, corncowpea intercropping system could be increased protein yield without decreasing of dry matter yield in comparison with corn monocropping system.

• 한국의류산업학회지
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• 제22권4호
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• pp.523-533
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• 2020

Previous studies are used to examine cellulose content, degumming period, fiber quality, production yield, production cost, development limit of fiber according to physical, chemical, and microbial degumming methods. Three types of degumming methods are used to measure surface condition after degumming, necessity of additional degumming and degree of impurity removal. First, previous studies confirmed that the microbial degumming method is superior in terms of cellulose content, fiber quality, production yield, production cost, and fiber development possibility. Second, surface condition and the necessity of additional degumming were analyzed by SEM. The black skin binding material was removed in the case of the Sangnangyi and chemical degumming; however, it was insufficient and further degumming was required. Skin fiber binding material was removed in the case of microbial degumming and the surface was cleanest after degumming; in addition, most showed the form of yarn decomposition. The FT-IR spectrum determined the degree of removal of impurities and showed that it can utilize inherent physical properties as the best degumming method. The degree of removal of pectin and lignin by microbial degumming was cleanest with hemicellulose also reduced by microbial degumming.

• 한국초지조사료학회지
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• 제16권1호
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• pp.69-74
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• 1996

This experiment was carried out to investigate to adaptability of forage rape(Brassica napus oleifera) and the determine its proper sowing time for a second cropping on the fallow field after sweet corn yield in the Hongchon area The forage rape, Ramon was sown at intervals of about ten days given eight different sowing times as treatments the early August to the middle October 1988. Plant height and DM yield were significantly higher for the early August(P<0.05) than for the other sowing times. Crude protein contents of the early August, mid August, mid September and late September were higher(P<0.05) 26.5, 24.3, 27.1 and 30.9% as much as that of the late August(l4.9%), respectively. Sowing time having high content of crude fiber shown low content of crude protein. Yields of crude protein were 3.52, 2.36, IAltha in the early, mid and late August, respectively. The highest crude protein yield was shown in the early August(P<0.05). Crude fiber yield was higher in early, mid and late August than in the other sowing times. These results indicate that forage rape sown in the early August as a second cmpping on the fallow field after sweet corn yield in Hongchon area, could be used as the high quality forage.

• 펄프종이기술
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• 제45권4호
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• pp.16-20
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• 2013

Yellow poplar grown in Korea and imported eucalyptus were compared their kraft pulping characteristics and evaluated the replacing possibility of eucalyptus by yellow poplar. Difference between yellow poplar and eucalyptus were investigated in chemical composition and fiber morphology. Yellow poplar kraft pulp resulted in the higher yield, longer fiber length and thicker fiber, and higher pulp strength than that of eucalyptus. More xylan survived in eucalyptus than yellow poplar during kraft pulping, which led to similar pulp yield even though polysaccharides in Eucalyptus was 4.5% less than in yellow poplar. Longer and thicker yellow poplar pulp fiber resulted in better beating response and pulp strength properties.