• 한국환경농학회지
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• 제14권3호
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• pp.338-344
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• 1995

현미중 카드뮴의 분석을 위한 보다 효율적인 방법을 찾기 위해 현미중 카드뮴의 공정시험방법을 표준으로 수종의 습식 및 건식방법에 대해 카드뮴의 회수율, 표준편차 및 표준방법과의 상관성등을 비교, 검토한 결과 현미 시료량 50g, 회화온도 $600^{\circ}C$의 건식방법은 회수율이 79.6%로 표준분석방법(87.2%)을 제외한 타 분석방법보다 높고, 표준편차도 평균${\pm}2.6$으로 표준분석방법의 평균+6.4 보다 약간 작았으며, 표준분석방법으로 분석된 카드뮴함량과의 상관성($r=0.977^{\ast\ast}$)도 크게 높아 본 방법은 습식으로 분해하는 현행 수질오염 공정시험 방법과 함께 현미중 카드뮴 분석방법으로 사용하여도 좋을 것으로 판단된다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.92-93
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• 2014

This study was carried out to process the shape of dry bottom ash using the impact crusher and gravity crusher, which are identified as most effective in improving grain shape through the preceding research, and a comparison was made between concrete that utilized the processed dry bottom ash as aggregate and concrete containing dry bottom ash before processing to understand properties of the new concrete.

• 한국건설순환자원학회논문집
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• 제3권1호
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• pp.7-14
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• 2015

본 연구의 목적은 건식공정을 통해 생산된 바텀애시를 이용하여 친환경적이고 저렴한 경량콘크리트의 잔골재로 활용하는 것이다. 기존의 습식공정과 비교하여 건식공정은 물에 닿지 않고, 염분이 없으며, 다소 느린 공정으로 완전연소를 통해 미연소탄소성분이 거의 없다. 이러한 건식공정 바텀애시를 경량 모르터용 잔골재로서 타당성을 평가하기 위해 골재의 입형 개선 효과와 최적 입도분포의 두가지 단계로 나누어 실험을 실시하였다. 첫 번째 실험에서 추가적인 마쇄과정을 통해 얻어진 양호한 입형의 바텀애시는 유동성과 강도 측면에서 양호한 결과를 나타내었으며 다소간의 단위용적질량 증가를 보였다. 두 번째 실험에서 다양한 입도를 구성하여 실험을 실시하였고, 그 결과 표준입도에 맞추어진 입도에서 굳지 않은 상태 및 경화상태에서 양호한 성능을 나타내었다. 본 연구의 결과를 통해 차후 건식 공정을 통한 바텀애시의 활용방법이 확대되고, 바텀애시를 경량 잔골재로 활용함으로서 부가가치 상승에 기여할 것으로 예상된다.

• 한국농공학회논문집
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• 제55권3호
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• pp.129-140
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• 2013

Bottom Ash is industrial by-product from a thermoelectric power plant. An immense quantities of bottom ash have increased each year, but most of them is reclaimed in ash landfill. In this study, in order to raise recycling rate of Bottom Ash, it is suggested to cure Bottom Ash (BA) mixtures mixed with cement, lime, Fly Ash (FA), and oyster shell (OS). Mixtures of 5~20 % mixing ratio had been cured for 1, 3, 7, 14, and 28 days using sealed curing and air-dry curing method. Unconfined compressive strength test was conducted to determine strength and deformation modulus ($E_{50}$) change for mixtures as mixing ratio and curing day, water contents of mixtures were measured after test. As a result, strength and $E_{50}$ were increased as mixing ratio and curing days, but values and tendencies of them appeared in different as kind of mixture, mixing ratio, curing method, and curing days. The results showed the addition of cement, lime, Fly Ash, and oyster soil in Bottom Ash could improved strength and $E_{50}$ and enlarge its field of being used.

• 한국지반환경공학회 논문집
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• 제17권9호
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• pp.29-35
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• 2016

Being mostly made up of highly permeable basalt and volcanic ash soil, Jeju Island's lithosphere characterizes its streams to be dry, flowing only when precipitation is happening. Under this condition, this research was motivated to identify the need of conservation of underground water, which is taking up most of (84% of) Jeju's water usage, and made an attempt to reduce the permeability of stream beds so that it can replace underground water and be used instead. To this end, this study suggested a simple method to make dry streams to carry water all-year-round by reducing permeability of stream floor. The experiment of permeability was performed on the porous basalt and compared it with that of same basalt with volcanic ash soil and Jumunjin sand layer added on top. The results showed a dramatic decrease in permeability of water when both volcanic ash soil and Jumunjin sand is were layered on top of porous basalt. Despite being gained in a controlled environment with a simple test, this result may provide a realistic and effective method of preserving Jeju Island's underground water which ultimately is a method of resolving water related issues.

• 한국초지조사료학회지
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• 제18권2호
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• pp.113-122
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• 1998

This experiment was conducted to establish the cultural method of triticale(Triticum Secalotriticum Saratoviense Meister) as a whole crop silage by evaluating the effect of seeding date and nitrogen fertilization rate on forage yields and feeding value. Heading date, flowering date, and the dough stage of development came significantly earlier as triticale was seeded earlier. Soilage, dry matter yields and percent dry matter significantly varied with seeding dates and crude ash, NFE and TDN. However, TDN yield was significantly reduced by delayed seeding. Macromineral contents were not affected by seeding date. Soilage, dry matter yield, and percent dry matter significantly increased as nitrogen fertilization rate increased. The contents of crude protein, crude fat, crude ash, NFE, TDN and TDN yield also significantly increased. In contrast, crude fiber content of triticale decreased with increasing N fertilization rate.

• 한국안전학회지
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• 제14권4호
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• pp.135-141
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• 1999

This study is an experimental study to investigate the possibility of the utilization of paper ash as the cover, liner in waste disposal landfill and other construction materials. The sample used in these tests was obtained from Daehan paper mill. A series of tests were peformed to evaluate basic properties, compaction, permeability, compressive strength, consolidation, leaching, and CBR of paper ash. In order to investigate the soil engineering properties of paper ash, the test results were compared with those obtained of fly ash. The results of unconfined compression tests show that paper ash had a larger strength than the fly ash. Also, the maximum dry unit weight of paper ash was approximately 59～76.9% less than that of the fly ash. It was found from the results of leaching test that paper ash is classified as non-detrimental general wastes according to the waste management law.

• 대한본초학회지
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• 제33권1호
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• pp.85-91
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• 2018

Objectives : This study was carried out to evaluate the quality of different drying methods and different roots(primary root and lateral root) of Angelica gigas Nakai. Methods : The experimental method was performed according to the Korea Pharmacopoea Eleventh edition (KP11). Loss on drying, ash, acid insoluble ash, ethanol extract, nodakenin and total decursin contents were tested to evaluate the quality of root tissue of Angelica gigas Nakai. In addition, the treatment of different root parts were prepared in two groups of washing dry process and natural dry process. Results : In comparison of dry processing methods, total contents of nodakenin and total decursin in the primary root and lateral root through washing dry process were ranged from 3.55 to 4.09% and from 5.18 to 6.13%, respectively. And also, those of roots from the natural dry process were from 4.36 to 6.22% and from 6.28 to 8.34%, respectively. In the washing dry process and natural dry process methods, 47.9% and 22.3% higher amount of nodakenin and total decursin were measured in lateral root compared to primary root. In common, lateral roots accumulated higher contents of nodakenin and total decursin compared to primary roots, and samples drying processed with natural dry process compared to washing dry process method contained higher amount of compounds. Conclusions : We sincerely hope that this study will be contributed to the standardization and quality control of Angelica Gigas Root.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2003년도 학술.기술논문발표회
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• pp.61-65
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• 2003

Bottom ash among the coal ash is not used because of its poor properties. But encouraging the use of bottom ash as a construction material is a sensible method of utilization as it avoids the problems and costs associated with disposal and provides an alternative aggregate source. This study was aimed at using bottom ash as an alternative fine aggregate source to provide a solution to disposal and insufficient fine aggregate for the production of concrete. So properties of domestic bottom ash were estimated due to the difference of each domestic bottom ash. And compressive strength and durability were estimated as basic data to use bottom ash in building industries. As a result of the experiment, the very porous surface and angular shape of the bottom ash particles necessitate a higher apparent water-cement ratio. And due to the higher water requirement, the compressive strength and durability of mortar is lower than those of the control samples. But when 25 percent of the total dry weight of the natural fine aggregate was replaced by bottom ash, the engineering characteristics were similar.

• Journal of Mechanical Science and Technology
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• 제15권6호
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• pp.804-812
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• 2001

A triboelectrostatic separation system for removing unburned carbon from coal fly ash is designed and evaluated. Fly ash from a coal-fired power plant is used as an accepted additive in concrete where it adds strength, sulfate resistance and reduced cost, provided acceptable levels of unburned carbon are maintained. Unfortunately, unburned carbon in coal fly ash absorbs some of other additives and reduces the concrete strength. This paper describes to investigate dry triboelectrostatic process to separate unburned carbon from coal fly ash and utilize it into economically valuable products. The laboratory-scale triboelectrostatic separation system consists of a particle feeding system, a tribocharger, a separation chamber, and collection systems. Particles of unburned carbon and fly ash can be imparted positive and negative surface charges, respectively, with a copper tribocharger due to differences in the work function values of the particles and the tribocharger, and can be separated by passing them through an external electric field. Results showed that fly ash recovery was strongly dependent on the electric field strength and the particle size. 70wt% of fly ash containing 6.5wt% of carbon contents could be recovered at carbon contents below 3%. The triboelectrostatic separation system showed a potential to be an effective method for removing unburned carbon from coal fly ash.