• The Journal of the Korea Contents Association
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• v.15 no.3
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• pp.427-437
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• 2015

Concrete, as a construction material, needs suitable reinforcement for tensile region due to weak tensile strength. Many researches on cement reduction have been attempted for $CO_2$ emissions during cement clinker production. In this paper engineering properties of concrete enhanced with polypropylene fiber (PPF) and rice husk ash (RHA) are evaluated. Fiber volume ratios of 0.125~0.375 and RHA replacement ratio of 0~20% are considered for concrete mixture. Lots of test including compressive, split, flexural and the related crack width, impact energy, and pull out test are performed and the results are evaluated considering the fiber ratios, fiber length and RHA replacement. Fiber and RHA ratios have dominant effects on tensile and compressive characteristics respectively, and the concrete with 0.125% of PPF and 10% of RHA shows the most effective enhancement for engineering properties. Appropriate addition of RHA and PPF are very effective both for engineering property enhancement and clean technology.

• Journal of Biosystems Engineering
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• v.22 no.1
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• pp.21-29
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• 1997

왕겨 재를 분쇄하여 콘크리트 混和용 재료로 이용하려는 연구의 일환으煙로서, 파이로트 規模의 多目的 왕겨 燒却爐를 設計, 裂作하고 그 性能을 分析하였다. 왕겨 燃燒時의 熱에너지는 回收하여 원예施設의 煖房이나 콘크리트의 高溫 養生水로써 이용하고자 熱交煥裝置를 제작하여 왕겨 燒각爐시스템에 장착하였고, 排煙가스내의 이산화탄소가 시설원예 作物의 光合成에 이용될 수 있는지 排煙가스의 造成을 조사하였다. 분쇄된 왕겨 재의 큰크리트 混和材로서의 적합성은, 燃燒 灰分의 성분 중 $SiO_2$ 의 結晶化 상태를 分析함으로써 判斷하였다. 연구결과를 要約하면 다음과 같다. 1. 왕겨 灰分의$SiO_2$ 結晶化는 燃燒온도 $750^circ C$ 이하에서는 거의 발생하지 않는 것으로 분석되었다. 2. 燒却爐의 작동은 매우 만족스러웠으며 最適 작동조건은 왕겨供給率 15kg/h. 制御온도 $600^{\circ}C$로 分析되었다. 最適 작동조건에서, 왕겨燃燒率은 97%, 熱交換機 效率은 59.5%, 전체 시스템의 熱效率은 57.7%로서 양호하였으며, 灰分의 $SiO_2$ 結晶化도 거의 발생하지 않아 生成된 왕겨 灰分은 훌륭한 큰크리트 混和在로 판단 되었다. 3. 燒却爐내 溫度分布는 대체로 均一하였으며, 排煙가스내의 大氣오염물질 중, 질소酸化物과 황酸化物 함량은 許容기준치보다 매우 낮았으나 일산화탄소 함량은 許容기준값 부근으로 나타나 排煙가스를 직접 원예시설 내에 공급하기 위해서는 약간의 연소실 구조 개선이 필요하다고 판단되었다.

• Korean Journal of Agricultural Science
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• v.25 no.1
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• pp.89-96
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• 1998

This study was performed to evaluate the engineering properties of permeable polymer concrete with rice-husk ash. The following conclusions were drawn; 1. The highest sterngth was achieved by 50% filled rice husk-ash permeable polymer concrete, it was increased 24% by compresseve, 123% by tensile and 90% by bending strength than that of the normal cement concrete, respectively. 2. The static modulus of elasticity was in the range of $1.27{\times}10^5{\sim}1.75{\times}10^5kgf/cm^2$, which was approximately 58~70% of the normal cement concrete. The higher elastic modulus was showed by 50% filled rice-husk ash permeable polymer concrete, relatively. The poisson's number of permeable polymer concrete was less than that of the normal cement concrete. 3. The ultrasonic pulse velocity was in the range of 2,503~3,083m/sec, which was showed about the same compared to that of the normal cement concrete. The higher pulse velocity was showed by 50% filled rice-husk ash permeable polymer concrete. 4. The water permeability was in the range of $4.612{\sim}5.913{\ell}/cm^2/hr$, and it was largely dependent upon the mix design. These concrete can be used to the structures which need water permeability.

• Korean Journal of Agricultural Science
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• v.24 no.2
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• pp.207-217
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• 1997

This study was performed to evaluate the engineering properties of rice-husk ash concrete using normal portland cement, natural aggregates and rice-husk ash. The following conclusions were drawn; 1. The unit weight was in the range of $2,216{\sim}2,325kgf/m^3$, the weights of those concrete were decreased 1~6% than that of the normal cement concrete, respectively. 2. The highest strength was achieved by 10% rice-husk ash filled rice-husk ash concrete, it was increased 8% by compressive strength, 17% by tensile strength and 18% by bending strength than that of the normal cement concrete, respectively. 3. The ultrasonic pulse velocity was in the range of 3,252~4,016 m/s, which was showed about the same compared to that of the normal cement concrete. The highest ultrasonic pulse velocity was showed by 10% rice-husk ash filled rice-husk ash concrete. 4. The dynamic modulus of elasticity was in the range of $242{\times}10^3{\sim}306{\times}10^3kgf/cm^2$, which was showed about the same compared to that of the normal cement concrete. The highest dynamic modulus was showed by 10% rice-husk ash filled rice-husk ash concrete. 5. The static modulus of elasticity was in the range of $185{\times}10^3{\sim}275{\times}10^3kgf/cm^2$, which was showed about the same compared to that of the normal cement concrete. The poisson's number of rice-husk ash concrete was less than that of the normal cement concrete. The dynamic modulus was increased approximately 11~30% than that of the static modulus. 6. The durability was increased with increase of the content of rice-husk ash. The durability was increased 1.3 times by 10% rice-husk ash, 1.6times by 20% rice-husk ash filled concrete than that of the normal cement concrete. respectively.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1999.07a
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• pp.307-312
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• 1999

현재 우리나라에서 매년 생산되는 농산부산물은 볏짚, 왕겨 등이 주를 이루는데 에너지원으로서 적당한 것은 왕겨이다 하지만 왕겨는 단순히 농업의 부산물로 여겨질 정도로 농민들의 소득증대에의 기여도가 매우 낮다. 또한 왕겨는 내외피가 규소로 치밀하게 피복되어 있으므로 부식퇴기 어려움에도 불구하고 왕겨를 축사의 깔개로 이용 후 퇴비화함에 따라 농지내 왕겨 환원속도가 부식속도 보다 빨라서 토양속에 미부식 왕겨가 누적되어 농지내 토양환경을 열악하게 하고 있으며 왕겨를 축사내 깔개로 이용함에 따라 어린 가축의 생육장애 등이 제기피고 있으며 장래에는 악취로 인한 대기오염 문제와 가축의 질병 문제 등이 추가로 제기될 가능성이 많다. (중략)

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.111-117
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• 2017

This study examined the material properties of Korean rice husk ash (RHA) according to the manufacturing process, and evaluated the feasibility of its use as a new admixture for high strength concrete. For this purpose, its particle size distribution, chemical composition, and microstructure were analyzed under various parameters, such as calcination temperature ($400^{\circ}C$, $650^{\circ}C$, and $900^{\circ}C$) and the inclusion of a milling process. X-ray fluorescence analysis confirmed that the silicon oxide ($SiO_2$) content of RHA was improved to more than 92% with a calcination process at $650^{\circ}C$ or higher. In addition, microstructural analysis showed that the RHA calcined at $650^{\circ}C$ has a porous structure. Because of this, the absorption capacity of the RHA was improved. On the other hand, when the milling process was applied, the porous structure was destroyed; thus, the absorption capacity tended to decrease further. Based on the analysis results, it was concluded that RHA calcined at $650^{\circ}C$ can be used as an admixture for high strength concrete, which possesses functions of both a shrinkage reducing agent and a pozzolanic activator.

• Korean Journal of Poultry Science
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• v.33 no.1
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• pp.65-80
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• 2006

Ash amendment to manure holds potential as a method to neutralize manure for reducing odor and reduce phosphorus (P) solubility in runoff from fields where manure has been applied. This review focuses on the literature published about ash characteristics and their environmental uses. There is no uniform physico-chemical definition of the selected ashes (coal fly ash-CFA, wood ash-WA, and rice hull ash-RHA) used in various studies. These ashes vary greatly in their acidity (pH<6.0) or alkalinity (pH>12.5) based on the conditions at which they were farmed and the composition of the ash source. CFA amendment to manure reduced manure-P solubility and application of CFA amended manure to agricultural soils is a method to improve water quality WA may prove to be a valuable manure odor control amendment since WA contains a high level of carbon. A major biomass source is rice hull (husk) which provides an ash source (RHA). The .ice hull and RHA are sources of silica, compromising about 20% and 60%, respectively. So far research has been directed at the use of CFA, WA and RHA as soil amendments, but there is potential use of these materials as manure additives to sequester P and reduce odors.

• Cement
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• s.108
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• pp.61-66
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• 1987

• Journal of the Korean Wood Science and Technology
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• v.34 no.3
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• pp.38-45
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• 2006

The main objective of this study is the improvement of the interfacial adhesion of RHF-polypropylene (PP) bio-composites through NaOH and acetic acid treated RHF. After manufacturing of untreated and NaOH and acetic acid treated RHF filled PP bio-composites, the effect on interfacial adhesion of bio-composites was investigated. Tensile strength of the bio-composites made from treated RHF with NaOH and acetic acid was higher than that of the untreated bio-composites. The RHF surface before and after NaOH and acetic acid treatment was clearly confirmed by scanning electron microscopy (SEM) micrograph. It was found that both treatments result in a removal of impurity materials of RHF surface by SEM micrographs. The chemical structures of untreated and NaOH and acetic acid treated RHF were confirmed by fourier transform infrared (FTIR). The crystallization structure and crystallinity of non-treated, NaOH and acetic acid treated RHF were investigated by wide-angle X-ray scattering (WAXS).

• 레미콘
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• no.9 s.33
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• pp.72-78
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• 1992