• Journal of Biosystems Engineering
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• 제33권4호
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• pp.248-252
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• 2008

An experiment was conducted in order to investigate gasification characteristics of rice husks in a fixed bed, which was a pre-step to design a continuous gasification system. Two air supply levels for gasification were chosen and their effects on the producer gas amount and producer gas composition were discussed. The main components of the producer gas were CO, $CO_2$, $O_2$, $H_2$ and THC (Total HydroCarbon). As airflow rate decreased, more producer gas was produced. The peak amount of CO, $H_2$ and THC were 28%, 7.5% and 0.68% in volume when constant airflow rate of $3.36\;m^3/s$ was used in the batch operation. About 4.5 kg of ash (9%) and condensed water including tars of 6 kg (11%) were produced from 50 kg rice husks in the gasification. Excluding the byproducts, all rice husks seemed to be transformed into producer gas. This gasification study was conducted prior to developing a continuous gasification system for biomass including agricultural byproducts.

• Asian-Australasian Journal of Animal Sciences
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• 제17권2호
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• pp.207-212
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• 2004

Ruminal digestion of dry matter (DM) and neutral detergent fiber (NDF) of processed (ensiled, deepstacked or composted) broiler litter (BL) was determined in situ and in vitro, and compared with rice straw (RS). DM disappearances at 24 and 48 h and digestion of differently processed BL were higher than those of RS. Compared with RS, processed BL was low in NDF disappearance at 72 h incubation, digestion rate ($K_dB$) and digestibility at 0.025 of passage rate; however, deepstacked BL was similar in these NDF characteristics. Processing of BL affected ruminal digestion of nutrients such as DM and NDF adversely. NDF of composted BL, especially, was the most indigestible. This in situ nutritional evaluation indicated that deepstacked BL, the most widely used form of BL, was superior in DM characteristics (fractions, ruminal disappearance and digestibility) and similar in NDF characteristics (ruminal disappearance and digestibility) to RS.

• Asian-Australasian Journal of Animal Sciences
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• 제13권8호
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• pp.1084-1093
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• 2000

An in vitro gas production system was used to investigate the influence of various substrate mixtures on a natural mix of rumen microbes by measurement of fermentation end-products. The treatments were combinations of cassava (15.0, 30.0 and 45.0%) with different roughage sources (ruzi grass, rice straw or urea treated rice straw). Microbial biomass, net $^{15}N$ incorporation into cells, volatile fatty acid production, gas volume and rate of gas production increased linearly with increasing levels of cassava inclusion. There was also an effect of roughage source, with rice straw being associated with the lowest values for most parameters whilst similar values were obtained for ruzi grass and urea treated rice straw. The results suggest that microbial growth and fermentation rate increase as a function of readily available carbohydrate in the substrate mixture. A strong linear relationship between $^{15}N$ enrichment, total volatile fatty acid production and gas production kinetics support the suggestion of the use of the in vitro gas production system as a tool for screening feedstuffs as an initial stage of feed evaluation.

• Journal of Biosystems Engineering
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• 제18권4호
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• pp.402-409
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• 1993

During all mechanical processes rice plants are subjected to verious forces such as natural load of wind and mechanical load of agricultural machines. A force is always accompanied by deformation, which must be either sufficiently great for pressing or sufficiently slight in order to avoid damage. The mechanical behavior of the rice plants is determined by three variables : force, deformation and time. And they must be studied using rheological methods to determine their viscoelastic properties. This study is conducted to experimentally determine the mechanical and rheological properties of the rice stalks subjected to radial load. The force relaxation tests are performed under constant deformation, during which the reduction of forces over time is measured. The mechanical models were developed from the abtained data. The results were as follows : 1. The relaxation behavior of a rice stalk in radial compession may be described by a generalized Maxwell model consisting of 3 Maxwell elements in parallel. 2. Relaxatiom intensity always decreased with increased time of relaxation. 3. The rate of deformation has a significant effect on the relaxation behavior. having increasing pattern with an increase in rate of deformation. 4. The relaxation intensity and residual deformation increased with increased initial load. 5. The relaxtion of the intermediate portion of stalk was bigger tham that of the upper and lower portions.

• 대한영양사협회학술지
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• 제23권1호
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• pp.14-26
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• 2017

The purpose of this study was to determine the optimal recipe of rice cookies with two different amounts of Stevia rebaudiana leaf and grape seed oil, using a central composite design (CCD). In addition, mixing conditions of rice cookies were optimized by sensory evaluation and mechanical and physicochemical analysis using response surface methodology (RSM). RSM was used to obtain 10 experimental points (including two replicates of Stevia rebaudiana leaf and Grape seed oil), and the formulation of Stevia rebaudiana leaf added rice cookies was optimized using rheology. The results of mechanical and physicochemical analysis showed significant values for lightness, redness, yellowness, hardness, spread factor, loss rate, leavening rate, sweetness, moisture, pH, and density (P<0.001), results of the sensory evaluation showed significant values for color, flavor, taste, texture, appearance, and overall quality (P<0.05). As a results, optimal sensory ratio was found to be 1.98 g of Stevia rebaudiana leaf and 37.94 g of Grape seed oil.

• Preventive Nutrition and Food Science
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• 제9권3호
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• pp.199-205
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• 2004

The effect of chitosan on enzymatic activities and on bioactive compounds was characterized during germination at $25^{\circ}C$ for 7 days to search for a method to produce a germinated black rice. The germination rate was reduced by the addition of lactate and chitosan. The rotting rate was greatly decreased by chitosan, suggesting that the addition of chitosan into a germination solution might be an effective method for controlling fungal contamination during the germination of cereals. The addition of 100 and 200 ppm chitosan increased $\alpha$-amylase activity after 7 days by up to 152 % and 197 %, respectively. The activities of $\beta$-amylase and $\beta$-glucosidase were lower with 200 ppm chitosan than in distilled water and 100 ppm lactate. The amount of total soluble phenolics and total flavonoids decreased rapidly for four days and thereafter remained constant until the seventh day. The antioxidant activity of germinated black rice, in terms of hydrogen-donating activity, increased slowly and did not correspond to the changes of total soluble phenolics and total flavonoids. The amount of phytic acid was reduced by the addition of 200 ppm chitosan compared to distilled water, indicating that chitosan could be used as an elicitor for the increase of phytase activity during the germination of black rice.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 봄 학술논문 발표대회
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• pp.225-226
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• 2021

Recently, environmental problems have emerged as a major issue all over the world due to an increase in carbon dioxide(CO₂). The amount of CO₂ generated during cement production accounts for 6% to 8% of domestic CO₂ emissions and a solution to reduce CO₂ emissions the construction industry is trying to use mineral admixtures to reduce cement. Since digestion has no firing process the advantage of it is that there is no air pollution to occur. In this study, we studied the compressive strength of binary non-cement mortar containing rice husk powder extracted from digestion by the ratio of 10%, 20%, 30%, 40%. As a result, the table flow was increased when the mixing rate of rice husk powder extracted from digestion was higher, and the highest compressive strength was shown when the rice husk powder extracted from digestion mixing rate was 10%.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.119.2-120
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• 2003

Seed-borne fungal pathogens on rice seeds were investigated in order to evaluate their effect on rice grain quality. Rice seeds of two cultivars, Ilmibyeo and Daesanbyeo were collected from 27 areas of Korea and the fungal parasites on seeds were isolated by using a blotter method. Isolation frequency and number of species were varied from collection areas of seed samples. A total 13 species of fungi were identified from the seeds. Among them, Altemana alternata was the most frequent over the country. Bipoiaris oryzae most commonly from Gyeongbuk and Jeonbuk, Alternaria padwickii from Jeonbuk, and Nigrospora oryzae from Choongnam. However Bipolaris. oryzae, Alternaria padwickii, and Nigrospora oryzae were the most frequently isolated fungi from Gyeongbuk and Jeonbuk, and Chungnam, respectively. B. oryzae, A. alternata, A. padwickii, and N. oryzae were dominants on Ilmibyeo showing 10.3％, 10.2％, 5.2％, and 5.2％ infection rate, respectively. While, N. oryzae, A alternata, and Cladosporium sp. were most frequently isolated fungi from Deasanbyeo revealing 15.1％, 9.6％, and 7.5％ infection rate, respectively. These fungi inhabiting on hulls or endosperms of rice seed might be considered as potential factors decreasing rice grain quality. Further investigation of the fungi on grain rice quality are undergoing.

• 한국작물학회지
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• 제51권spc1호
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• pp.30-34
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• 2006

남부 산간고랭지에서 고품질 쌀 생산을 위한 질소시비량을 구명하고자 $2002{\sim}2004$년에 남부 산간고랭지 인 운봉에서 삼천벼를 공시하여 질소시비량에 따른 생육, 수량구성요소, 쌀 수량 및 품질 관련형질을 조사한 결과를 요약하면 다음과 같다. 1. 단위면적당 수수와 입수는 다비할수록 많았으나, 등숙비율과 현미천립중은 다비할수록 저하되었다. 2. 백미 외관상 품위에서 완전립 비율은 질소시비량이 많을수록 낮았고, 아밀로스 함량은 질소시비량 간에 별 차이가 없었으나, 단백질 함량은 질소시비량이 증가됨에 따라 다소 높아지는 경향이었다. 3. 쌀 수량과 완전미 수량은 질소 9 kg/10a 수준까지는 증수 되었으나 그 이상의 질소시비량에서는 수량 차이가 인정되지 않았다. 4. 따라서 남부 산간고랭지에서 완전미 수량, 완전미비율, 미질, 등숙비율 등을 고려한 품질향상을 위한 적정 질소시비량은 10a당 9 kg 내외로 판단된다.

• 한국작물학회지
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• 제41권6호
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• pp.625-633
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• 1996

파속 식물체 내에 있는 활성물질을 추출 분리하여 생물검정하고, 이들 작물의 경엽을 직접 pot에 시용하여 벼를 재배하였을 때 생육 및 수량 구성 요소에 미치는 영향은 다음과 같다. 1. 벼 유묘의 발근 및 생육을 촉진시키는 물질은 마늘의 염기성 분획과 대파, 양파, 부추 및 마늘의 약산성 분획에서 공통적으로 억제 물질보다 촉진물질의 활성이 높았으며 억제물질은 그 외 분획에서 활성이 높았다. 제 2엽초의 신장촉진 혹은 억제 물질은 공시한 파속 식물에는 내재하지 않았다. 2. 이앙 후 벼 유묘의 고사률은 이앙 당일에 비해 이앙 10일 전에 경엽을 시용한 처리가 높았고 특히 대파와 양파에 비해 부추와 마늘 시용구에서 높았다. 이앙 10일 전 동엽시용은 유효분얼수를 현저히 촉진시켰으며 특히 대파의 50g에서 400g까지, 양파의 50g에서 200g까지는 이삭입수의 증가도 나타나 표준시비구에 비해 수량 증가효과를 가져왔다.