• 한국연초학회지
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• 제28권2호
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• pp.83-93
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• 2006

The aim of this study is to develop a simple and rapid field method for the determination of chloride content in tobacco green or cured leaves. To set up a practical process, several factors such as the proper sampling position of each leaf, the size of leaf lamina pieces for blending, the substitution of deionized water fur the extracting solution, 0.1N $HNO_3$, the submerging durations before blending, and the standing times before measuring were studied using flue-cured and burley tobacco with a stable and reproducible Chloride Meter, KRK CL-2Z. From the results, chloride contents of tobacco leaves could be analyzed with the Chloride Meter(CL-2Z) using the suspension of 14 mm diameter leaf disks after soaking in distilled water for 30 min., blending with a mini-blender for 30 seconds. The chloride contents measured in this way showed highly significant correlations with ones by the conventional potentiometric method using an ion meter-chloride electrode and $AgNO_3$ titration. In our method, the procedures such as drying, powdering and weighing samples, and using chemical reagents for extraction (0.1N $HNO_3$) and titration(0.028N $AgNO_3$) could be eliminated. These results suggest that the newly constructed method using the Chloride Meter is more efficient to determine the chloride content of tobacco leave in comparison with the one by the Ion $Meter:AgNO_3$ titration.

• 한국지역사회생활과학회지
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• 제23권4호
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• pp.537-552
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• 2012

This study was conducted to investigate the quality characteristics of cooked rice with cereals frequently consumed in Korea by blending ratio. Seven kinds of cereals, white rice, glutinous barley, brown rice, black rice, glutinous rice, glutinous foxtail millet and proso millet, were chosen for the study. According to the results from rapid viscosity analyzer, glutinous barley had the lowest pasting temperature($66.55^{\circ}C$) and black rice had the highest values in the peak(231.77 RVU), trough(162.25 RVU), final viscosity(295.81 RVU) and set back(64.05 RVU)(p<0.05). Water absorption rate by soaking time for black rice and brown rice was increased only 18.77% and 14.57%, respectively, even after 120 minutes, whereas those of other cereals were increased up to 20.28~39.32% after 50 minutes. The pasting characteristics of white rice blended with cereals tended to be lower than white rice in the peak, trough, and final viscosity. Textural property of cooked white rice blended with black rice, brown rice, and glutinous foxtail millet showed a significantly higher value for hardness than that of cooked white rice only(p<0.05). The most preferred blending ratio of the respective cereals was 25% for glutinous barley, 10% for black rice, brown rice and proso millet, and 5% for glutinous foxtail millet and glutinous rice in the sensory evaluation for overall quality, but there were no significant differences except glutinous barley, brown rice and glutinous foxtail millet.

• 자원리싸이클링
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• 제24권6호
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• pp.61-68
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• 2015

본 연구에서는 천연수경성석회(NHL) 모르타르에 바잘트 섬유를 혼합하여 섬유혼합에 따른 강도특성을 연구하고자 하였다. 건식 및 습식 4가지로하여 혼합방법에 따른 물리적 특성발현을 확인하였으며, 압축강도 및 휨강도 등을 고려하여 강도 특성이 최대로 발현되는 혼합방법 한 가지를 선택하였다. 실험결과 물성 발현은 습식혼합보다 건식혼합에서 더 우수하였으며, 건식혼합 중 바인더(NHL)와 섬유를 pre-mixing 한 후 물과 골재를 순차적으로 혼합하여 섬유의 분산력을 높여주는 혼합방법을 선택하였다. 이후 섬유 길이에 따른 물리적 특성 발현성을 확인하였다. 바잘트 섬유 길이에 따른 압축강도 및 휨강도 측정결과, Plain 샘플 대비 섬유 혼합에 따라 압축강도는 감소하는 경향성을 보였으며, 휨강도는 증가하는 경향을 나타내었다. 또한 섬유를 혼합한 샘플 중에서 섬유길이 6 mm일 때 가장 우수한 강도 특성을 나타내었다.

• 한국조경학회지
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• 제27권3호
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• pp.109-113
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• 1999

The objective of this research was to develop growth media for artificial ground by blending calcined clay and coconut peat. To achieve this, aggregates of clay particles were mixed with disel oil and heated to high temperature(1150~120$0^{\circ}C$) to expand clays. The particle sizes of expanded clay were controlled to 2~5mm in diameter. Then expanded clayes were mixed with coconut peat and changes of soil physicochemical properties and their effect on plant growth of Hedera L. were determined. The infiltration rate of calcined clay was very high, but the water holding capacity, the cation exchange capacity(CEC), and the nutrient contents were low. The characteritics of coconut peat was vice verse to calcined clay. This indicates that the mixture of calcined clay and coconut peat have the better characteristics than each material. As compared to mineral soil, the infiltration rate, the water holding capacity, the CEC and the nutrient contents increased, but bulk density decreased to about 1/4. And, Hedera L. grown in the mixture of calcined clay and coconut peat(6:4, v/v) had higher plant height, longer leaf length, more total number of leaves per plant and fresh weight than that grown in mineral soil, but statistical differences were not observed between two treatments.

• 펄프종이기술
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• 제44권4호
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• pp.91-98
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• 2012

This study was carried out in order to evaluate the effects of ultra fine precipitated calcium carbonate (UFPCC) on properties of coating color, coated paper and off-set printability. It was found that blending of UFPCC increased the low-shear viscosity and water retention of coating color. The smaller the particle size, the more significant the effect of it. When the blending ratio of UFPCC was increased, brightness, whiteness and opacity of the coated paper were improved, while paper gloss was decreased due to the increase in roughness. When the UFPCC with the average particle size of $0.12{\mu}m$ was used, the ink receptivity during off-set printing was improved while print gloss was maintained or a little decreased. It was also observed that the dry-pick and wet-pick strength of coated paper were improved by the use of UFPCC. In conclusion, it is possible to produce the low gloss matt paper with the use of UFPCC since it could improve the optical properties and ink receptivity of coated paper.

• 한국지반신소재학회논문집
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• 제16권4호
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• pp.221-230
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• 2017

선행 연구에서 PVP를 이용하여 수용성 폴리머 파우치를 개발하였다. 그러나 개발된 재료의 용융점이 매우 낮아 재료의 성형 시 문제점이 많아 대량생산 시 필요한 성형, 제작이 불가능하였기에 성형성이 우수한 새로운 재료 조합을 이용하여 폴리머 파우치를 개발하였다. 새롭게 선정된 PEG의 수용성 변화 및 지반공동 내 보강 시 파우치의 기계적 물성을 만족해야한다. 따라서 PEG와 LLDPE, TALC 블렌딩 비율에 따른 특성평가를 실시하였는데 각 원료의 비율에 따라 발생하는 성질이 다르기 때문에 실험을 통해 적정 비율을 찾는 것이 중요하기 때문이다. 이러한 블렌딩을 통해 수용성 특성은 유지하며 인장 및 충격강도가 증진된 폴리머 파우치를 개발하였다. 최종 개발된 제품을 이용하여 직접전단 실험을 실시한 결과, 폴리머 파우치의 지반강도 효과를 확인할 수 있었다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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• pp.225-228
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• 2006

To clarify the one body behavior of reinforcing bar and concrete, it is important to investigate bond characteristics between two materials. Bond strength is decided by applied force and interface area between reinforcing bar and concrete. And, the resultant force of chemical adhesive force, frictional force, and mechanical interaction are to be main factors. Property of concrete influences on chemical adhesive force and frictional force; bond strength is decreased by corrosion of reinforcing bar, as the result, durability is also decreased. In this study, to confirm bond characteristics with property of concrete, w/c ratio and blending of mineral admixture were selected as the main test parameters. The results obtained from this study will be used as the basic data for bond characteristics with corrosion.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1995년도 가을 학술발표회 논문집
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• pp.256-261
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• 1995

Large-scaling recycling of demolished concrete will concrete will contribute not only to the solution of a growing waste disposal problem, it will also help to consweve natural resoures of sand and gravel and to secure future supply of reasonly priced aggregates for building and other construction purposes within large urban areas. Because recycled aggregate particles consits of substantial amount of relatively soft cement paste component, it is less resistant to mechanical actions. With this view in mind, to obtain a reference data for the development of recycling system and to a basic data the guiedline of recycled aggregate concrete construction and engineering properties of recycled aggregate concrete according to the factors, such as blending ratio of recyced aggregete with the natural aggregate, addition to the factors, such as blending ratio of recycled aggregete with the natural aggregate, addition of flyash, water coment ratio.

• 한국세라믹학회지
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• 제27권7호
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• pp.833-840
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• 1990

For the development of multi-functional materials which has water reducing power, air entraining power and waterproofing power as well as blending additive in cement mortar the coal ash was modified with asphalt-stearic acid or asphalt-boiled oil mixtures by mechanical treatment. And the physical properties of cement mortar blended with modified coal ashes were compared with those of the water-tightness-cement mortar and the ordinary-portland-cement mortar added with AE.water reducing agent. The mortar of coalash-blend-cement modified with asphalt-stearic mixture was increased acid about 20% in initial strengths and decreased about 20% in water absorption ratio than those of ordinary coalash-blend-cement. The mortar of coalash-blend-cement modified with asphalt-bolied oil mixture was similar to the cement mortar added with AE.water reducing agent in water reduction ratio, air entraining conents and the initial strengths, also was similar to the water-tightness-cement mortar in water absorption and water permeability ratios.

• Macromolecular Research
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• 제15권1호
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• pp.22-30
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• 2007

High water vapor permeable coating materials were prepared by blending aqueous poly(vinyl alcohol) (PVA) solution with waterborne polyurethane-urea (WBPU) dispersions synthesized by prepolymer mixing process. Stable WBPU/PVA dispersions were achieved at PVA content below 30 wt%. As the water soluble polymer PVA content increased, the number and density of total micro-pores (tunnel-like/isolated micro-pores) formed after the dissolution of PVA in water increased, and the water vapor permeability of coated Nylon fabric also increased significantly. Using WBPU/water soluble polymer PVA blends as a coating material and then dissolving PVA in water was confirmed to be an effective method to obtain prominent breathable fabrics.