• KSBB Journal
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• v.19 no.3
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• pp.226-230
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• 2004

Fermentation characteristics of D-xylose into xylitol by Candida mogii ATCC 18364, a potential xylitol producer from rice straw hemicellulose hydrolyzates, were investigated. The influences of the most important operational variables on xylitol production were examined. The best results in xylitol production were obtained in shake-flask fermentations when 3.0 g/L initial cell concentration of 12 hr-old cells grown in D-glucose containing medium were used as inoculum. The oxygen availability is a critical factor in xylose fermentation, therefore, xylose conversion into xylitol was investigated in a 2-L fermenter at different stirring rates. Maximum xylitol production was obtained with an aeration rate of 1 vvm at a stirring rate of 200 rpm.

• Asian-Australasian Journal of Animal Sciences
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• v.4 no.1
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• pp.31-40
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• 1991

Four pairs of draught oxen (two local and two Jersey crossbred) were studied when they ploughed dry land on local farms. Work done, distance traveled and body temperature of each ox were measured continuously over a 5 h working day. A different team worked each day, completing at least six days work each. Individual food intakes and digestibility of feed were measured when the animals were given rice straw and tree fodder, and housed and fed according to local husbandry practices. The Jersey crossbreds, particularly the longer legged type, had a higher rate of work than the local oxen in this study. They did significantly more work and covered a greater distance during the day. The absence of a hump in the crossbred oxen had no effect on the position of the yoke or the way the oxen pulled when ploughing. The longer legged type of Jersey crossbred tended to work more erratically than any of the other teams. A fast rate of work made the oxen more liable to heat stress. When fed according to local practices and given the same amount of feed as local oxen, Jersey crossbreds tended to do less well. During the ploughing months, the local oxen gained weight, while the crossbreds remained at the same or lost some weight. Although there were some disadvantages to keeping Jersey crossbreds for work, their favourable work output suggests that the introduction of the Jersey crossbred in the hills of Nepal is unlikely to be detrimental to the performance of the work oxen population.

• Journal of Microbiology and Biotechnology
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• v.19 no.11
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• pp.1421-1430
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• 2009

With an aim to evaluate dye decolorization by white rot fungus on natural living conditions, reproducing by solid-state fermentation, the process of triphenylmethane dyes decolorization using the white rot fungus P. ostreatus BP, cultivated on rice straw solid-state medium, has been demonstrated. Three typical dyes, including malachite green, bromophenol blue, and crystal violet, were almost completely decolorized by the fungus after 9 days of incubation. During the process of dye decolorization, the activities of enzyme secreted by the fungus, and the contents of soluble components, such as phenolic compounds, protein, and sugar, changed regularly. The fungus could produce ligninolytic, cellulolytic, and hemicellulolytic enzymes and laccase was the most dominant enzyme in solid-state medium. Laccase, laccase isoenzyme, and the laccase mediator could explain the decolorization of malachite green, bromophenol blue, and crystal violet by the fungus in solid-state medium, respectively. It is worth noting that the presence of the water-soluble phenolic compounds could stimulate the growth of fungus, enhance the production of laccase, and accelerate dye decolorization.

• Journal of Biosystems Engineering
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• v.6 no.1
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• pp.48-59
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• 1981

The major limiting factor on the determination of combine capacity is the frequent occurence of clogging over the some parts of machine when the crop is wet in the case of Japanese self-feeding type combine. And in the case of American conventional combine having big separating parts, the great grain loss and damage occur when the machine is used for rice harvesting. This experiment was carried out to develop the new type threshing and separating equipment. Proto-type thresher which consist of a conical threshing drum and a conical separating sieve rotating around the threshing cone was constructed and tested. In the case of 800 rpm of threshing cone speed, average threshing loss was below 1 percent, separating loss was about 1 percent, grain damage was about 0.4 percent, and average total power required was about 2.6 PS. This design has some problems such as higher power required or wrapping problems under the conditions of feeding long damp straw. But, compared with the conventional combine or thresher, this machine certainly has some potentials for this approach to combine development. The crop feed rate must be increased through improvement of the feeding portion of the threshing cone. And it is required to investigate further about some parameters causing wrapping phenomena.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.3
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• pp.202-208
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• 2014

This study was carried out investigate the effects of dietary addition of mineral and sugar on the dry matter intake, daily gain, yield grade and quality grade of Hanwoo (Bos taurus coreanae) steers. Three diets fed to steers included a control diet (concentrate mix and rice straw : C) and two treatments diet (control diet + black sugar 100 g + mineral 100 g : T1, and control diet + black sugar 150 g + mineral 50 g : T2). The results are summarized as follows; total feeding intake, body weight gain and daily gain did not show significant differences among the three treatments. Cold carcass weight was significantly (p<0.05) higher in T2 than in the other two treatments (C and T1). There was no significant difference in yield traits of back fat thickness, longissimus muscle area and yield grade among the three treatments (C, T1 and T2). Marbling score showed significantly (p<0.05) higher in order of T2 (5.67) > T1 (4.67) > C (3.67). Meat color, fat color, texture and maturity were no significant difference. Quality grade was higher in T2 than in the other two treatments (C and T1), but there was no significant difference. The results show that marbling score and quality grade of Hanwoo can be increased by high dry matter intake with feeding addition of mineral and sugar.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.4
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• pp.1-9
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• 2008

The utilization of non-woody fibers with the fast growing annual plants has occurred in the paper industry to replace wood and preserve environment of the earth. The non-woody fibers generally used for papermaking are paper mulberry, gampi, manila hemp, rice straw, bamboo, and coton linter etc.. Recently Kenaf has been spot-lighted for the same application. Kenaf is an annual plant of Hibiscus species of Malvaceae family. Kenaf, a rapid growing and high harvesting non-woody fiber plant, was identified as one of the promising fiber sources for the production of paper pulp. This study was carried out to investigate the pulping characteristics of Kenaf bast fiber for Hanji (traditional Korean paper) manufacturing by different pulping methods, such as alkali, alkali-peroxide and sulfomethylated pulpings. It was possible to make superior grade of Hanji. Especially sulfomethylated pulping was resulted in superior pulp in terms of higher yields and qualities in comparison to those of the other pulping methods. Hanji from sulfomethylated pulp was shown the highest brightness of over 60% and higher sheet strength. In addition, the morphological features of pulp fibers (pulp compositions) affect to the sheet properties. Therefore the effect of fiber distribution index(FDI) which was calculated from the data of Confocal laser scanning microscopy(CLSM) on the sheet properties of Kenaf Hanji was also discussed.

• Korean Chemical Engineering Research
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• v.53 no.2
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• pp.216-223
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• 2015

The present work explores the potential of wet air oxidation (WAO) for pretreatment of mixed lignocellulosic biomass to enhance enzymatic convertibility. Rice husk and wheat straw mixture (1:1 mass ratio) was used as a model mixed lignocellulosic biomass. Post-WAO treatment, cellulose recovery in the solid fraction was in the range of 86% to 99%, accompanied by a significant increase in enzymatic hydrolysis of cellulose present in the solid fraction. The highest enzymatic conversion efficiency, 63% (by weight), was achieved for the mixed biomass pretreated at $195^{\circ}C$, 5 bar, 10 minutes compared to only 19% in the untreated biomass. The pretreatment under the aforesaid condition also facilitated 52% lignin removal and 67% hemicellulose solubilization. A statistical design of experiments on WAO process conditions was conducted to understand the effect of process parameters on pretreatment, and the predicted responses were found to be in close agreement with the experimental data. Enzymatic hydrolysis experiments with WAO liquid fraction as diluent showed favorable results with sugar enhancement up to $10.4gL^{-1}$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.85-92
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• 2000

This study was carried out to storage of Pleurotus ostreatus packed in various trays made by different matrials-expanded polystyrene (EPS), rice straw pulp(RP), and RP trays coated with starch, carboxyl methyl cellulose (CMC), polyacrylamide (PAM), alkylketen dimer (AKD), rosin size (RS) and polyethylene glycol (PEG) at 8~1$0^{\circ}C$ and 70~80% relative hymidity for 6 days. At 6 days storage, weight increase of RP and CMC tray was lower (p<0.05) than those of others and the weight of oyster mushroom packed in RP, CMC and AKD tray decreased lower(p<0.05) than those of others. Carbon dioxide contents in trays were increased from 0.5% to 5.5%~8.6% within 1 day storage. Oxygen contents in trays were sharply decreased from 20% to 0.8%~8.2% within 1 day storage. Lightness of oyster mushroom increased all trays. Off flavor appeared stronly in oyster mushroom packed in EPS, AKD and PEG during storage, but was not detected in mushroom packed in starch and CMC until 4 days storage.

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.3
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• pp.29-36
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• 2012

This study was carried out to investigate the runoff characteristics in paddy field using livestock compost fertilizer. Irrigation, runoff and water quality data in the paddy field were analyzed periodically from May to September in 2011. The observed amounts of rainfall, irrigation, runoff for the experimental paddy field during the irrigation period were 1,148.2 mm, 523.9 mm, and 344.7 mm, respectively. T-N concentrations ranged from 2.28 mg/L to 11.75 mg/L, which was generally higher than the quality standard of agricultural water (1.0 mg/L). T-P concentrations ranged from 0.018 mg/L to 0.241 mg/L and the average was 0.122 mg/L. The runoff loads of T-N and T-P were 15.7 kg/ha and 0.4 kg/ha, respectively. The runoff pollutants loadings in T-N and T-P in this study were much lower values than the loads of T-N and T-P from the paddy field presented by others' studies. We are considering that these results were affected by rainfall as well as hydrological condition, irrigation water, fertilizer application, rice straw and plowing.

• KCID journal
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• v.18 no.1
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• pp.94-102
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• 2011

The aim of this study was to evaluate the load of non-point sources pollutant at a paddy plot located at the valley watershed during irrigation period. Irrigation, runoff and water quality data in the paddy plot were analyzed periodically from June 1 to October 31 in 2005. The observed amount of precipitation, irrigation, runoff for the experimental paddy plot during the irrigation period was 1,297.8, 223.2, and 825.4mm, respectively. Total-N concentrations ranged from 3.73 to 18.10mg/L, which was generally higher than the quality standard of agricultural water (1.0mg/L). Total-P concentrations ranged from 0.111 to 0.243mg/L and the average was 0.139mg/L. The observed runoff pollutants loadings from the paddy plot were measured as 34.4 kg/ha for T-N, 1.0 kg/ha for T-P and 213.8 kg/ha for SS. The non-point sources pollutant load in drainage water depends on rainfall and surface drainage water amount from the paddy plot. We are considering that these results were affected by rainfall as well as hydrological condition, soil management, whether or not fertilizer application, cropping, rice straw and plowing.