• Advances in concrete construction
• /
• 제3권3호
• /
• pp.223-236
• /
• 2015

Concrete is the most widely used material of construction. Concrete gained the popularity as a construction material due to the easy availability of its component materials, the easy formability, strength and rigidity upon setting and curing.In construction industry, strength is the primary criterion in selecting a concrete for a particular application. Now a days, the substantial amount of waste materials, containing the properties of the Pozzolana, is being generated from the major industries; and disposal of such industrial wastes generated in abundance is also a serious problem from the environmental and pollution point of view. On this backdrop, efforts are made by the researchers for exploring the possible utilization of such waste materials in making the sustainable construction material. The present paper reports the experimental investigations to study the strength characterization of concrete made from the pozzolanic waste materials. For this purpose, the Pozzolanic materials such as fly ash and ground granulated blast furnace slag were used as a cement replacing materials in conjunction with ordinary Portland cement. Equal amount of these materials were used in eight trial mixes with varying amount of cement. The water cement ratio was also varied. The chemical admixture was also added to improve the workability of concrete. The compressive strengths for 7, 28, 40 and 90 days' were evaluated whereas the flexural and tensile strengths corresponding to 7, 28 and 40 days were evaluated. The study corroborates that the pozzolanic materials used in the present investigation along with the cement can render the sustainable concrete.

• 생약학회지
• /
• 제38권1호
• /
• pp.90-94
• /
• 2007

This study was examined the chemical components and total phenol content in acorn powders of Korea and China. Korea acorn powder produced from consists of 6.85% crude protein, 3.57% crude fat and 3.33% crude ash. China acorn powder consists of 1.83% crude protein, 0.41% crude fat and 0.40% crude ash. The composition of unsaturated fatty acid of Korea acorn powder was slightly lower than China acorn powder, but there was no significant difference. The amino acid content of Korea acorn powder was higher than that of China acorn powder. Total phenol content of that Korea acorn powder was 20 mg/g, and that China acorn powder was 3.2 mg/g.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
• /
• pp.193-196
• /
• 2005

In this study, the purpose is to suggest the data on mixing ratio which effects on the carbonation of concrete by replacing various admixture such as silica fume, fly ash, slag powder. Thus, we have experimented the accelerated test on the carbonation related to hardened body of the concrete which was admixed by slag powder, silica fume, fly ash and it was cured for 4 weeks in carbonation accelerator after 28 days curing water. The result of this experiment showed that carbonation speed increased highly when admixtures be used to replacing by growing of admixture ratio. especially, the test sample which was replaced with silica fume 15$\%$ and slag powder 40$\%$, was promoted highly to carbonation.

• 한국식품영양과학회지
• /
• 제29권2호
• /
• pp.188-192
• /
• 2000

To obtain basic information for the quality evaluation, the introduced or domestic sesame seeds were investigated to measure proximate components (crude protein, ash, mineral and oil) and isolated by preparative HPLC system for lignan contents. Although crude protein contents were the highest in Sudan sesame seeds, lipid, ash and mineral contents were not significantly(p<0.05) different between introduced and domestric sesame seeds. Unsaturated fatty acids such as oleic and linoleic acids were the highest in the domestic sesame seeds. The Mg content of domestic sesame seeds also was larger than that of introduced sesame seeds. A Ca content of domestic sesame seeds, however, was significantly (p<0.05) lower than that of China. Lignan contents, the most important component known as antioxidant, were significantly (p<0.05) higher in domestic sesame seeds than other sesame seeds tested. Our findings suggest that domestic sesame seed has the best quality in terms of the functional components.

• Journal of Forest and Environmental Science
• /
• 제26권2호
• /
• pp.75-82
• /
• 2010

The biometry, morphological properties and chemical composition of bagasse, corn, sunflower, rice, and rapeseed residues plants were analyzed. The results revealed differences in biometry properties and chemical composition of the different types of agricultural resides investigated. The greatest proportion of fiber length (1.32 mm) and cellulose (55.56%) was found in residues of bagasse plants, with a low ash (1.78%) and lignin (20.5%). The lignin of all types of agricultural resides was less than hardwood and softwood. In addition, the rice and rapeseed residues plants had highest amount of ash and extractive component. The slenderness and flexibility ratios of the all types of agricultural resides fibers were similar to some of hardwood and softwood species.

• Applied Biological Chemistry
• /
• 제6권
• /
• pp.51-56
• /
• 1965

누수과다답(漏水過多沓)에서 미분탄회(微粉炭灰)의 시용(施用)이 수도수량(水稻收量) 및 수량구성요소(收量構成要素)에 미치는 영향(影響) 및 규산고토석회(硅酸苦土石灰), 석회(石灰) 등(等)과의 비효(肥效)를 비교(比較)하고저 실험처리구(實驗處理區)로 10a당(當) 규산고토석회(硅酸苦土石灰) 75kg구(區), 석회(石灰) 150kg구(區), 미분탄회(微粉炭灰) 75kg구(區), 150kg구(區), 225kg구(區), 300kg구(區), 375kg구(區), 450kg구(區) 및 무처리대조구(無處理對照區)를 두고 수도품종(水稻品種) 팔달(八達)을 공시(公試)하여 실험(實驗)하였는데 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. 미분탄회(微粉炭灰), 규산고토석회(硅酸苦土石灰) 및 석회(石灰)의 시용(施用)은 무처리(無處理)에 비(比)하여 각구(各區) 모두 수도생육(水稻生育) 및 수량(收量)을 증대(增大)시키는 경향(傾向)을 보였다. 특히 수량구성요소적(收量構成要素的)으로 보면 임실율(稔實率)을 높이는데 효과(?果)가 컸다. 2. 미분탄회(微粉炭灰)의 시용(施用)은 그 양(量)을 증가(增加)시킬수록 수량(收量)도 증가(增加)되는 경향(傾向)을 보였는데 10a당(當) 300kg 이상(以上)의 시용구(施用區)에 있어서는 큰 차이(差異)가 인정(認定)되지 않았으며, 이것은 규산고토석회시용구(硅酸苦土石灰施用區)의 수량(收量)과 거의 비슷한 것이었고 미분탄회(微粉炭灰) 225kg 시용구(施用區)는 석회시용구(石灰施用區)와 거의 그 수량(收量)이 동등(同等)하였다. 3. 따라서 미분탄회(微粉炭灰)의 시용량(施用量)은 10a당(當) 300kg내외(內外)가 효과적(?果的)인 것으로 보인다.

• 한국결정성장학회지
• /
• 제22권5호
• /
• pp.254-259
• /
• 2012

순환유동층 연소방식의 화력발전소에서 석탄을 연소시킨 후 발생하는 석탄재 중 탄산화 반응 인자인 Ca 성분을 다량 포함한 비산회를 시멘트에 일정량 치환하여 제조한 인공경량 경화체를 초임계상태에서 이산화탄소($CO_2$)를 고정화하여 골재의 기계적 물성향상을 도모하였다. 초임계 분위기 $40^{\circ}C$ 조건에서 비산회의 치환량을 변화시켜 재령일수별 탄산화를 시행하였다. 비산회 치환량에 따른 탄산화 반응시킨 인공경량골재 경화체의 무게변화율, TG/DTA 분석, 1 % 페놀프탈레인 알칼리성 측정을 통하여 탄산화 진행여부를 확인하였으며 28일까지의 재령 이후 경화체의 압축강도 측정과 비중측정을 통하여 골재의 기계적 물성향상과 인공경량골재의 기준 비중치인 2.0 이하의 비중값을 갖는 탄소고정 인공경량골재 경화체를 얻는 것이 가능할 것으로 판단되었다.

• 한국환경보건학회지
• /
• 제7권2호
• /
• pp.73-87
• /
• 1981

Generation of Solid Wastes grew rapidly with the increase of living standard of the people in Korea recently and their composition was more complicate. The weight of Solid wastes generated in Seoul into year of 1979 was about 420 million tons which required 1.5 million $m^2$ of burial land and daily generation for person was 1.6kg. The Composition of more than 80% ash contents was suitable for sanitary landfill but recently ash was decreasing while paper, synthetic materials, glass etc, increasing and alternative method had to be found to dispose the wastes properly. Weight and Composition of Wastes by season and living standard were surveyed for one year from June 1980 to May 1981 in Seoul. Disposal mathods by waste composition was studied. Results were summarized as follows: 1) Each component stored separately at generation point was to be collected and to be reused or disposed by public organization or private company. Some incentives have to be arranged. 2) Wastes collected from household were transfeted to about 420 temporally storing places and transported to two dumping areas by about 700, 4-8 tons trucks which droped litters on the streets. Large dumping lots should constructed along the western coasts and the wastes would be transported through big container trucks or trains to the lots. 3) Ash contents decreased to 40-70% while garbage, synthetic materials, paper increased and they are two to three times in summer of those in winter. Ash in affluent residential areas is less than 50% of whole wastes while that in poor apartment and residential areas is 60-70%. 4) Large dumping places should be constructed along the western coasts which are not far from Seoul because no suitalbe lands are available, and proper leakage protection arrangements should be made.

• 유기물자원화
• /
• 제18권2호
• /
• pp.84-92
• /
• 2010

본 연구는 강원도 T시를 중심으로 생활폐기물의 물리화학적 특성을 조사하여 생활폐기물의 적정관리 방안 및 처리방법에 활용할 수 있는 기초자료를 제공하고 하고자 실시되었다. 조사결과 T 시의 겉보기밀도는 평균 $231kg/m^3$이었으며, 가연성분과 비가연성분은 각각 94.0%와 6.0%이었다. 가연성분 중 음식물류폐기물(32.3%)과 종이류(41.2%)는 최근의 타 지역에 비하여 여전히 높은 비율을 차지하고 있어 철저한 분리배출이 필요하였다. 삼성분 중수분, 가연분, 회분의 함량은 각각 41.3%, 50.5%, 그리고 8.2%이었으며, 원소조성 중 탄소, 수소, 산소, 질소, 황, 염소의 함량은 각각 51.4%, 6.3%, 26.7%, 1.1%, 0.2%, 0.5%를 나타내었다. 습윤저위발열량은 2,704 kcal/kg으로 춘천시의 2,764 kcal/kg와 유사하였으나 과거 구로구, 고양시의 1,467~1,584 kcal/kg 보다는 1,000 kcal/kg 이상 높았다. 또한 조제된 소각재의 용출시험 실시결과 모두 지정폐기물 판정 기준치를 크게 하회하여 큰 문제가 없는 것으로 나타났다.

• 한국연초학회지
• /
• 제17권2호
• /
• pp.177-183
• /
• 1995

This study was conducted to develop the most precise NIR(near infrared spectrometric) calibration for rapid determination of chemical composition in ground samples of toasted burley tobacco using stepwise, stepup, principal component regression(PCR), partial least square(PLS) and modified partial least square(MPLS) calibration method. The number of wavelength(W) selected by stepup multiple linear regression using: second derivative spectra was as follows: total sugar(TS)-4 W, nicotine-9 W, total nitrogen(TN)-2 W, ash-8 W, total volatile base(TVB)-5 W, chlorine4 W, L of color-6 W, a of color-6 W and b of color-7 W. Comparing the calibration equations followed by each chemical components, the most precise calibration equation was MPLS for 75, a and b of color, PLS for nicotine, ash, TVB, chlorine and L of color and stepup for TN. The standard error of calibration(SEC) and standard error of performance(SEP) between result of near infrared analysis and standard laboratory analysis were 0.18, 0.40% for 75, 0.06, 0.08% for nicotine, 0.18, 0.16% for TN, 0.33, 0.46% for ash, 0.04, 0.03% for TVB, 0.08, 0.06% for chlorine, 0.54, 0.58 for L of color, 0.22, 0.22 for a of color and 0.27, 0.27 for b of color, respectively. The SEC and SEP of ash and TVB were within allowable error of standard laboratory analysis, nicotine, TN and chlorine were 1.2-2.0 times and 75 were 2.1-4.0 times larger than allowable error of standard laboratory analysis. The ratio of SEC and SEP to mean were 1.5, 1.6% for L of color, 3.7, 3.8% for a of color and 1.8, 1.8% for b of color, respectively. Key words : burley tobacco chemistry, near infrared spectroscopy.