• 접착 및 계면
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• 제9권3호
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• pp.27-33
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• 2008

무기계 킬레이트의 일종인 aluminum acetylacetonate (AlACA)를 점착제의 -COOH 당량비에 따라 0, 0.25, 0.5, 0.75, 1의 비율로 변화 시키고, 점착제는 acrylic acid의 함량을 3 wt%, 7 wt%, 10 wt%으로 변화를 시켜 그에 따른 경화거동을 살펴 보았다. 킬레이트의 함량이 증가하면서 가교 구조가 형성되고, 이에 따라 probe tack의 fibrillation이 줄어들고, peel strength도 줄어드는 경향을 보였다. SAFT의 경우 점착제의 acrylic acid 함량이 증가함에 따라 확연히 증가하였다. 본 연구 결과, aluminum acetylacetonate는 점착물성을 크게 변화시키지 않는 범위에서 점착제를 가교 시킬 수 있음을 확인하였다.

• 한국추진공학회지
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• 제24권4호
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• pp.66-72
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• 2020

본 논문은 알루미늄 함량 변화에 따른 추진제의 후경화에 대한 영향성, 화학적 노화도에 관하여 기술하였다. 동일 경화조건에서 알루미늄 함량이 18 wt%인 추진제가 2 wt%인 추진제 대비 후경화 기간이 길어지는 것으로 확인하였다. 반면 후경화가 포함된 화학적 노화도 분석에서는 알루미늄 함량이 18 wt%인 추진제가 2 wt%인 추진제 대비 화학적 노화가 천천히 진행되는 것을 확인하였다.

• 한국주조공학회지
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• 제26권3호
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• pp.123-128
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• 2006

Mechanical and thermal properties of spray-cast hypereutectic Al-20wt.%Si-xwt.%Fe alloys (x=0, 1, 3, 5) were investigated. After the spray-casting, hot extrusion was performed at $400^{\circ}C$. Intermetallic compound (${\beta}-Al_5FeSi$) and primary Si are observed in the spray-cast aluminum alloys. The size of primary Si and intermetallic compound of the spray-aluminum alloys became finer and more uniformly distributed than that of the permanent mold cast ones. Ultimate tensile strength of the spray-cast aluminum alloys increased by increasing Fe contents, but that of the permanent mold cast aluminum alloys decreased by increasing Fe contents possibly due to increased amount of coarse intermatallic compound. The coefficient of thermal expansion (CTEs) of the aluminum alloys became lower with finer primary Si and intermetallic compound, and this is attributed to the increased amount of interfacial area between the aluminum matrix and the phases of finer Si and intermetallic compound.

• 한국환경과학회지
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• 제21권3호
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• pp.377-382
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• 2012

Recent research has demonstrated that treating poultry litter with alum (aluminum sulfate) and aluminum chloride can remove environmental threats (ammonia, soluble phosphorus and odor) posed by litter. However, scientific information available on heavy metal in poultry litter with liquid aluminum chloride is still lacked. The purpose of this study was to investigate the effects of applying liquid aluminum chloride to rice hulls on heavy metals and to provide basic information to producers. Six hundred 0-d-old broiler were assigned to 4 treatments (control, 100 g, 200 g and 300 g of liquid $AlCl_3$/kg of rice hulls, respectively) with 3 replicates of 50 birds. The experimental period lasted for 6 weeks. Liquid $AlCl_3$ was sprayed on the rice hulls surface using a small hand pump. Total Al contents increased (P<0.05) with the increasing levels of liquid $AlCl_3$ levels over time in comparison with control groups. Total Cu and Pb were lowered in all liquid $AlCl_3$ treatments compared with the controls during 6 weeks. Significant differences in all treatments were found for total Cu contents at 2, 3 and 5 weeks and total Pb at 0, 1, 2 and 3 weeks. Total Zn contents decreased with time when compared with controls. However, no significant differences in total Zn contents were observed among all treatments. In light of environmental managements, spraying liquid $AlCl_3$ to rice hulls indicated the significant advantages in reducing heavy metals as well as improving poultry industrial competitiveness.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1998년도 추계학술대회 논문집
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• pp.505-511
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• 1998

Production technologies for aluminum rolling stocks are mainly related to welding of aluminum alloys. Automatic welding of extrusion profiles and control of welding deformations are the important contents of the production technologies. Another production technology other than welding is the technique for surface treatment of aluminum carbody. In this paper, problems caused during construction of the test carbody are described and the remedies for the problems are suggested. The accumulated experiences and systematic data will be helpful for the mass production of aluminum rolling stocks in the furture.

• 한국물환경학회지
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• 제20권3호
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• pp.281-289
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• 2004

Optimal analytical conditions have been established for mixing and reaction coil length, concentrations of ECR, CTAB, and acetate, reaction temperature and pH in the determination of aluminum by using flow injection analysis(FIA). Detection limit and repeatability for this system were $3{\mu}g/L$ and better than 1% of relative standard deviation, respectively. The interference from iron(III) was suppressed up to 6mg/L of iron(III) by $0.1{\mu}M$ ascorbic acid, and the interference from fluoride could be tolerated in absorption of Al/ECR/CTAB derivative by 10mM boric acid at pH 3.5 adjusted with nitric acid. This FIA system was applied to the determination of aluminum leached from cooking utensils by distilled and tap water containing fluoride ranged from 0.5 to 2mg/L by measurement of absorbance for Al/ECR/CTAB at 585nm. The leached aluminum content was increased with increasing concentration of fluoride. The aluminum contents leached from aluminum utensils by tap water were about 9 fold higher than those leached by distilled water, whereas aluminum contents leached by distilled water containing fluoride were about 2 fold higher compared to those leached by distilled water. That represented that other dissolved substances as well as fluoride in tap water contributed to liberation of aluminum from aluminum utensils. A comparison between FIA data and ICP-AES data by correlation and paired t test showed that the FIA system could be accepted as a good alternative method for the determination of aluminum in tap water.

• 한국추진공학회지
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• 제23권5호
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• pp.60-66
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• 2019

본 논문은 알루미늄 함량 변화에 따른 로켓보조추진탄(RAP) 용 추진제의 공정특성(점도), 기계적 물성, 연소특성, 지상 및 비행시험 결과에 관하여 기술하였다. 알루미늄 함량이 증가되면 초기점도는 감소하고 점도 build-up은 빨라지며 연소속도 및 압력지수가 감소하는 것을 확인하였다. 지상연소시험에서는 알루미늄이 10 wt% 함유된 RAP이 알루미늄이 2 wt%, 18 wt% 함유된 RAP에 비해 총역적이 약 5% 높았으며, 이론성능 대비 모터 효율은 알루미늄이 18 wt% 함유된 조성이 85.6%로 가장 낮았다.

• 한국식품영양과학회지
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• 제23권5호
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• pp.863-866
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• 1994

여러 금속 원소 가운데 유해하지 않은 것으로 알려진 알루미늄 재질의 용기나 화합물의 사용이 증가하고 있어서 알루미늄의 허용수준에 대한 연구의 필요성이 대두되고 있으나 그에 대한 연구가 거의 없는 실정이어서 이의 기초자료를 얻고자 여러 가지 대중적인 음료식품 가운데, 유산균 음료, 탄산 음료, 과실 음료, 과실 통조림 등에 대한 알루미늄 함량을 원자흡수분광광도법으로 분석한 결과는 다음과 같다. 3개 제조사의 유산균음료중 액상요구르트는 161.667~173.333ppm, 호상 요구르트는 139.303~293.926ppm으로 호상요구르트 함량이 약간 높았다. 4개사의 캔 용기의 과실 음료와 탄산 음료는 각각 1,481~7,130ppm, 1,803~6,027ppm으로 이들 서로 간에 합량 차이는 크지 않았다. 3개사의 과실 통조림 중 포도 통조림은 5,661~5.927ppm, 복숭아 통조림은 4.600~7.053ppm의 범위였고, 3개 제조사의 차류 제품은 326.592~846.056ppm으로 그 중에서 녹차의 함량이 846.056ppm으로 제일 높았다.

• 열처리공학회지
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• 제7권2호
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• pp.139-146
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• 1994

In the molten state, magnesium alloys vigousey react with oxygen in the air, is protected from oxidation and burning by the addition of $SF_6$ to $CO_2$ atmosphere over the melt. The mechanical properties and metallographic examinatin have made of Mg-Al alloys containing 3, 6, 9% in the solution treated state and precipitated state, comparing mechanical properties obtained during unidirectional solidification with me chanical properties obtained during conventional casting. For a given solution treatment, a higher aluminum contents produce more or less fine grains in conventional casting. For a given artifical aging treatment, a higher aluminum contents produces much precitates at the grain boundary as well as within the grain in unidirectional solidification. As a result of this experiment, for a given heat treatment, the higher is aluminum contents the higher is the ultimate tensile strength, yield strength, hardness while the lower the elongation. Also the mechanical properties of unidirectional solidification is larger than that of conventional casting.

• 한국물환경학회지
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• 제28권1호
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• pp.50-56
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• 2012

In this study, loess composites, loess with lanthanum and with aluminum, were made and evaluated for treatment of phosphorus removal in natural water system. Desiccation method for production of loess composite was superior to centrifugation method in obtaining high concentrated composites of lanthanum and aluminum. Washing of loess lanthanum composite by water did not deteriorat the lanthanum concentration in the composite, but this lowered the aluminum concentration of loess aluminum composite. Total of 15 and 37.5% of aluminum contents were removed after first washing treatment in aluminum loess of 0.05% and 0.1% respectively. However, no more aluminum loss was monitored with increase of washing times. Phosphorus removal efficiencies were not decreased with washed loess aluminum composite. Phosphorus removal was successfully achieved by adsorption of phosphate to loess composite at pH range of 5.0 ~ 8.0. Freundlich and Langmuir adsorption isotherm was observed in the adsorption of phosphate for loess composite. Dosages of 0.05% and 0.1% lanthanum composite for 95% of phosphorus removal could reduce its usage amount to 25% and 50%, respectively, comparing with dosage of loess alone. Dosages of 0.05% and 0.1% aluminum composite could reduce its usage amount to 48% and 63%, respectively.