• 농업과학연구
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• 제38권1호
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• pp.95-100
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• 2011

In the present study, effects of autohydrolysis treatment on the properties of rice hull were investigated. Two temperature condition such as $160^{\circ}C$ and $180^{\circ}C$ and thee treatment time such as 15 min, 30 min and 45 min were applied for autohydrolysis treatment. The pH of extract after autohydrolysis treatment decreased as increasing of the temperature and the treatment time. The ash content and the lignin content of rice hull were not decreased by the autohydrolysis treatment. The structure of rice hull after autohydrolysis treatment became more weak, the better efficiency of the fiberization with PFI-Mill was shown for the autohydrolysis treated rice hull with the higher temperature and the longer treatment time.

• 펄프종이기술
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• 제39권4호
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• pp.61-67
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• 2007

Paper sludges collected from three different paper mills were physico-chemically analyzed in order to use them as raw materials for making bed soils and seedling pots. The sludge from a fine paper mill contained lots of inorganic pigment particles used for coating, as those from a newsprint mill and a tissue mill had not. It was clearly through XRD analysis confirmed that all sludges included calcium carbonate. The paper sludge from the tissue mill contained the greatest amount of particles, which would contribute to water absorption and nutrient storage. The sludge from the fine paper mill had the highest density due to many inorganic elements. While the ash content and the total nitrogen content were the highest in the sludge from the fine paper mill, the C/N ratio was the lowest in the fine paper mill sludge. All sludges seemed to have insufficient contents of potassium. The sludges from the newsprint mill and the tissue mill showed more silicon contents than that from the fine paper mill. It was concluded that the sludge from the fine paper mill would be able to be the most efficient raw materials for making bed soils and seedling pots and the other two sludges would be more efficient for intensive culture for crops such as rice and grain with additional supplement of nitrogen and other nutrients.

• 펄프종이기술
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• 제45권6호
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• pp.64-71
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• 2013

The biodegradable mulching paper could be applied for the environmental friendly agriculture as an alternative to the current vinyl mulching. In order to increase the usability of the mulching paper, the effects of the addition of various inorganic materials on the functionality of the mulching paper were evaluated in terms of practical benefits. The blend of carbonized rice husk powder and perlite resulted in the higher value in the air permeability of the mulching paper, which would be important for the health of plant root. The heat conservative of the mulching paper could be improved by adding the bottom ash or the fly ash because of the pore structure of the ashes. The pH of acidic soil could be neutralized by using the mulching paper containing paper-mill sludge ash or fly ash. The various results showed the addition of the inorganic materials could improve the functional properties of the mulching paper.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2011년도 춘계학술발표회 논문집
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• pp.139-150
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• 2011

The effects of the high pressure and the high temperature digesting process with water on the properties of rice hull were investigated in this work. Two temperature condition such as $160^{\circ}C$ and $180^{\circ}C$ and thee treatment time such as 15 min, 30 min and 45 min were applied for this treatment. The pH of extract after the digestion process decreased as the temperature and the treatment time of the digestion were increased. The ash content and lignin content were not decreased by the the digestion. The structure of rice hull after digestion treatment became more weak, the better efficiency of the fiberization with PFI-Mill was shown for the digestion treated rice hull with the higher temperature and the longer treatment time.

• 한국식품조리과학회지
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• 제25권1호
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• pp.106-118
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• 2009

This study was to investigated optimum preparation conditions for Gugija Heukimja jook by response surface methodology (RSM). The important materials used for the Gugija Heukimja product were Lycium chinese, Seasamum indicum L., Ziziphus jujuba Mill. and rice. Moisture content, crude protein, crude fat, crude ash and crude fiber content were 15.62, 16.60, 13.62, 4.93 and 11.17% for Lycium chinese, 3.62, 20.94, 43.56, 5.67 and 10.72% for Seasamum indicum L., 24.12, 5.38, 0.73, 2.30 and 1.25% for Ziziphus jujuba Mill., and 12.36, 6.98, 0.46, 0.43 and 0.41% for rice, respectively. Optimal extraction conditions of brix, color, pH and total acidity in the materials for Gugija Heukimja jook were temperature $80^{\circ}C$, water volume 850 mL and extraction time of 63 min. The spreadability of jook with Lycium chinese and Ziziphus jujuba Mill. extracts was the highest when black sesame was 12 g pH was the lowest when black sesame was 9 g. PH showed a significant difference when the added black sesame ratio changed. The 'value L' of chromaticity was lower with an increase of the black sesame ratio, 'value a' was higher with an increase of the black sesame ratio, 'value b' was lower with an increase of the black sesame ratio. Brix was lower when black sesame in jook was added. Total acidity was highest (7.27%) when black sesame was 12 g. The degree of gelatinization tended to be lower with additional black sesame. Higher scores of sensory evaluation were found for the product containing 9 g black sesame with Lycii furctus and Ziziphus jujuba Mill. extracts ompared to the other samples with 3 and 6g. No significant difference in taste occurred for Gugija Heukimja jook prepared with over 9 g black sesame, while a great difference showed in color, pH and total acid. Therefore, the Gugija Heukimja jook prepared under the optimal conditions of 9 g black sesame with Lycium chinese and Ziziphus jujuba Mill. extracts exhibited higher qualities. Gugija Heukimja jook can use the easier for Yacksun jook. It is expected to become functional in the product's development.

• 한국식품과학회지
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• 제25권6호
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• pp.769-774
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• 1993

Fluidized bed opposed jet mill을 사용하여 초미세분쇄한 후 Turboplex classifier로 공기분급한 탈지미강분말의 입도는 air classifying wheel speed (ACWS)가 낮아짐에 따라 입자의 크기와 표준편차는 증가하고 단위부피당 표면적은 감소하였다. ACWS 21,000rpm에서 분급한 미강분말의 형태는 구형이었으며 입도 median이 $3.7{\mu}m$이었다. ACWS별로 회수된 시료의 단백질, 지방, 회분은 ACWS에 따라 전반적으로 증가하는 경향이었다. Mg, Zn, Fe 및 Mn 함량은 ACWS가 증가할수록 비교적 증가하는 경향을 보였으며, phytic acid함량은 중간 ACWS에서 약간 높은 값을 보였다. 식이섬유함량은 $25.2{\sim}31.5%$의 값을 보였고, ACWS 15,000rpm에서 최대값을 나타내었다. ACWS에 따른 시료의 색도는 ACWS가 높을수록 백색도(L)가 증가하였고, 적색도(a)와 황색도(B)는 감소하는 경향을 나타내었다. 보수력(WHC)은 12,000rpm에서 2.88g/g solid로 가장 높았고 ACWS가 높아짐에 따라 감소하는 추세를 보였으나, 보유력은 반대로 ACWS에 따라 약간 증가하는 경향을 보였다. 분급된 미강분말 현탁액의 유동특성은 Bingham body에 속하였으며 농도와 ACWS가 증가함에 따라 항복응력 및 점도가 상승하였다. 분급된 미강분말을 5% 수준으로 대체하여 케이크를 제조한 경우 대조구보다 케이크의 높이와 부피가 증가하였다.

• Composites Research
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• 제31권5호
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• pp.209-214
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• 2018

본 연구에서는 친환경적이고 공급이 안정적인 소재를 찾기 위하여, Bio waste인 쌀겨와 조개 껍질에서 활용하여 마이크로 사이즈의 미세 입자를 추출하고, 추출한 입자의 크기와 형상을 분석한 후 CFRP에 첨가하여 물성의 변화를 관찰하였다. 쌀겨와 탄화 쌀겨의 주요구성성분은 탄소, 산소, 규소로 이루어졌으며 탄화과정을 거치면서 탄소와 규소의 비율이 증가함을 확인하였고, 조개 껍질 분말에서는 탄소 산소와 칼슘이 검출되었으며 이는 조개 껍질의 주요구성물질인 탄산칼슘의 영향으로 보인다. 쌀겨 분말의 면적평균은 $6.19{\mu}m$ 체적평균은 $14.77{\mu}m$으로 FE-SEM을 통하여 막대형상의 입자가 관찰되며 이는 쌀겨가 가지고 있던 껍질부분의 주름이나 표면의 털이 남아있는 형상으로 보인다. 탄화쌀겨의 분말은 면적평균은 $1.55{\mu}m$ 체적평균은 $8.20{\mu}m$ 조개 껍질 분말은 면적평균은 $2.53{\mu}m$ 체적평균은 $5.79{\mu}m$로 분석되었으며 쌀겨분말의 경우 막대(Rod)형상의 입자들이 관찰되었고, 조개 껍질 분말의 경우 판상(Plate)의 형상을 가지는 것으로 관찰되었다. CFRP에 첨가하였을 경우 첨가량에 비례하여 물성의 하락이 관찰되었는데 그 폭이 쌀겨분말의 경우가 가장 컸으며, 조개 껍질 분말의 경우 물성하락을 거의 유발하지 않음을 확인하였다.

• Advances in concrete construction
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• 제9권4호
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• pp.387-395
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• 2020

This study has been carried out in two-phases to develop Fiber Reinforced Self-Compacting Concrete (FRSCC) performance. In the first phase, the composition of the quaternary composite binder compromised CEM I 42.5N (58-70%), Rice Husk Ash (25-37%), quartz sand (2.5-7.5%) and limestone crushing waste (2.5-7.5%) were optimized. And in the second phase, the effect of two fiber types (steel brass-plated and basalt) was investigated on the SCC optimized with the optimum CB as disperse reinforcement at 6 different ratios of 1, 1.2, 1.4, 1.6, 1.8, and 2.0% by weight of mix for each type. In this study, the theoretical principles of the synthesis of self-compacting dispersion-reinforced concrete have been developed which consists of optimizing structure-formation processes through the use of a mineral modifier, together with ground crushed cement in a vario-planetary mill to a specific surface area of 550 m2 / kg. The amorphous silica in the modifier composition intensifies the binding of calcium hydroxide formed during the hydration of C3S, helps reduce the basicity of the cement-composite, while reducing the growth of portlandite crystals. Limestone particles contribute to the formation of calcium hydrocarbonate and, together with fine ground quartz sand; act as microfiller, clogging the pores of the cement. Furthermore, the results revealed that the effect of fiber addition improves the mechanical properties of FRSCC. It was found that the steel fiber performed better than basalt fiber on tensile strength and modulus of elasticity; however, both fibers have the same performance on the first crack strength and sample destruction of FRSCC. It also illustrates that there will be an optimum percentage of fiber addition.