Ni nanowires were fabricated using anodic aluminum oxide (AAO) membrane as a template by electrochemical deposition. The nanowires were formed within the walls of AAO template with 200 nm in pore diameter. After researching proper voltage and temperature for electrochemical deposition, the length of Ni nanowires was controlled by deposition time and the supply of electrolyte. The morphology and microstructure of Ni nanowires were investigated by field emission scanning electron microscope (FE-SE), X-ray diffraction (XRD) and transmission electron microscope (TEM).

In this study, the heat flow of the plant scale aluminum extrusion process was investigated to establish optimum continuous heat treatment conditions. During the extrusion of 6061 aluminum alloy, processing parameters such as the extrusion pressure, speed and temperature histories of billets were logged as a function of time. The surface temperature of the billets increased at constant ram speed, while it decreased with decreases of the ram speed. In order to maintain the billet temperature within a solutionizing temperature range prior to the succeeding water quenching step, the ram speed or the temperature of the blower should be controlled. The temperature histories of the billets during the extrusion and hot air blowing processes were successfully simulated by using the velocity boundary model in ANSYS CFX. The methodology to design an optimum process by using a commercial simulation program is described in this study on the basis of the metallurgical validation results of the microstructural observation of the extrudates. The developed model allowed the advantages of taking into account the motion of the extrudate coupled with the temperature change based on empirical data. Calculations were made for the extrudate passing through the isothermal chamber maintained at appropriate temperature. It was confirmed that the continuous heat treatment system is beneficial to the productivity enhancement of the commercial aluminum extrusion industry.

본 연구는 농도를 달리한 알루미늄 급여가 두충의 효과에 미치는 영향을 실시한 결과 식이섭취량에서 두충차 추출액과 알루미늄 병합급여군은 알루미늄 단독급여군에 비하여 증가하였으나 각 실험군간에 유의성은 나타나지 않았다. 음용수 섭취량은 알루미늄 단독 급여군에 비하여 알루미늄과 두충차 추출액 병합급여군이 약간 증가하였다. 체중 증가량은 대조군과 두충차 추출액 급여군에 비하여 농도를 달리한 알루미늄 급여군이 감소하였으며 식이효율은 각 실험군간에 유의적인 차이는 나타나지 않았다. 간, 심장, 신장, 폐, 위, 소장, 대장 및 비장 조직 중의 알루미늄 함량에서 대조군과 두충차추출액급여군 간에는 별다른 차이를 보이지 않았으나 각각의 농도를 달리한 알루미늄 급여군에 비하여 알루미늄과 두충차 추출액 병합급여군의 함량은 감소하였다. 레닌활성도에서 대조군에 비하여 두충차 추출액 급여군이 감소하였고, 각각 농도를 달리한 알루미늄 급여군에 비하여 알루미늄과 두충차 추출액 병합급여군이 유의적으로 감소하였다. 알도스테론농도는 각각 농도를 달리한 알루미늄 급여군에 비하여 알루미늄과 두충 추출액 병합급여군이 유의적으로 감소하였다. ALT와 AST는 농도를 달리한 알루미늄 단독 급여군에 비하여 알루미늄과 두충차 추출액 병합 급여군이 유의적으로 감소하였다. LDHase는 알루미늄 급여군에 비하여 알루미늄과 두충차 추출액 병합급여군이 감소하였으나 유의한 차이는 없었다. ChEase는 농도를 달리한 알루미늄 단독급여군에 비하여 두충차 추출액과 알루미늄 병합급여군 및 대조군과 두충차 추출액군이 유의하게 증가하였다. 따라서 알루미늄을 만성적으로 섭취하게 되면 독성효과를 나타낼 수 있으나 두충차추출액이 알루미늄에 의해 손상된 조직과 AST, ALT, LDHase. ChEase 활성도, 레닌, 알도스테론 호르몬 농도에 어느정도 영향을 미치는 것으로 나타나 두충의 폴리페놀 성분이 알루미늄에 의한 어느 정도 중독 완화 효과가 있으며, 본 실험은 흰쥐를 이용한 동물모델로 실시하였으나 알루미늄은 여러 경로를 통해 사람에게 노출 될 수 있으므로 알루미늄이 인체에 어떤 영향을 미치는지에 대한 연구는 계속되어져야 한다고 사료된다.

Transparent conducting aluminum-doped ZnO thin films were deposited using a sol-gel process. In this study, the important deposition parameters were investigated thoroughly to determine the appropriate procedures to grow large area thin films with low resistivity and high transparency at low cost for device applications. The doping concentration of aluminum was adjusted in a range from 1 to 4 mol% by controlling the precursor concentration. The annealing temperatures for the pre-heat treatment and post-heat treatment was 250˚C and 400-600˚C, respectively. The SEM images show that Al doped and undoped ZnO films were quite uniform and compact. The XRD pattern shows that the Al doped ZnO film has poorer crystallinity than the undoped films. The crystal quality of Al doped ZnO films was improved with an increase of the annealing temperature to 600˚C. Although the structure of the aluminum doped ZnO films did not have a preferred orientation along the (002) plane, these films had high transmittance (> 87%) in the visible region. The absorption edge was observed at approximately 370 nm, and the absorption wavelength showed a blue-shift with increasing doping concentration. The ZnO films annealed at 500˚C showed the lowest resistivity at 1 mol% Al doping.

This study was designed to investigate the effects of green tea extract on aluminum-induced damage to phospholipid content in old rat cerebral tissue. The aim of this study was to investigate the possibility that aluminum is the cause of Alzheimer’s disease. Forty Sprague-Dawley old male rats weighing 350±10 g were divided into four groups, consisting of a control group (CON), 40 ppm aluminum sulfate group (Al-40), green tea water extract group (GTWE), and 40 ppm aluminum sulfate and green tea water extract groups (Al-40+GTWE) and kept on their respective diets for 12 weeks. In order to discover the influence of aluminum on cerebral tissue of old male rats, the serum aluminum concentration and phospholipid composition were compared between the aluminum-treated group and the normal group. The results showed that the serum aluminum concentration was higher in the aluminum sulfate-treated group than in the normal group. The cerebral tissue phospholipid concentration decreased significantly in the aluminum sulfate treated group as compared to the normal group. The results of this experiment show that increase of aluminum concentration in experimental animals causes the rise of serum aluminum and phospholipid concentrations, phenomena that are very similar to those shown in Alzheimer’s disease., The results of this experiment, together with reports that aluminum is a cause of neurofibrillary tangles in cerebral tissue, therefore demonstrate the possibility that aluminum is the cause of Alzheimer’s disease. Green tea water extract is also shown to be an effective therapeutic candidate for the treatment of Alzheimer’s disease.

In this study, a new, relatively simple fabrication method for forming a mesoporous Al(OH)3 film onAl substrates was demonstrated. This method, i.e., alkali surface modification, was simply comprised of dippingthe substrate in a 5×10-3M NaOH solution at 80oC for one minute and then immersing it in boiling waterfor 30 minutes. After alkali surface modification, a mesoporous Al(OH)3 film was formed on the Al substrate,and its chemical state and crystal structure were confirmed by XPS and TEM. According to the results of theXPS analysis, the flake-like morphology after the alkali surface modification was mainly composed of Al(OH)3,with a small amount of Al2O3. The mesoporous Al(OH)3 layer was composed of three regions: an amorphous-rich region, a region of mixed amorphous and crystal domains, and a crystalline-rich region near the Al(OH)3layer surface. It was confirmed that the stabilization process in the alkali surface modification stronglyinfluenced the crystallization of the mesoporous Al(OH)3 layer.

Various inorganic fillers improve the thermal conductivity and physical properties of organic products. Alumina has been used a representative filler in the heat radiation sheet for the heat radiation of electric device. The high filling rate of alumina increases the thermal conductivity and properties of products. We successfully developed the spherical alumina by flame fusion process using the oxygen burner with LPG fuel. In the high temperature flame (25003000) of oxygen burner, sprayed powders were melting and then rotated by carrier gas. This surface melting and rotation process made spherical alumina. Especially effects of chemical composition and particle size of stating materials on the melting behavior of starting materials in the flame and spheroidization ratio were investigated. As a result, spheroidization ratio of boehmite and aluminum hydroxide with endothermic reaction of dehydration process was lower than that of the sintered alumina without dehydration reaction.

Efforts to reduce noise in industrial application fields, such as automobiles, aircrafts, and plants have been gaining considerable attention while a sound proof wall to protect people from the noise has been intensively investigated by many researchers. In this study, our research group suggested creating a new sound proof wall composed of scrap aluminum chips and perforated plates in a commercial polyester sound proof wall, which was then successfully fabricated. This wall's sound absorption characteristics were measured by an impedance tube method. The sound absorption property was evaluated by measuring the Noise Reduction Coefficient (NRC) to the standard, ASTM C 423-90a. The noise reduction coefficient of the sound proof wall composed of 3.5 vol.% and 7.5 vol.% of scrap aluminum chips relatively increased to 5% and 8% compared to the commercial polyester sound proof wall. The scrap aluminum perforated plate also relatively increased to 13% compared to the commercial polyester sound proof wall.

This study was performed to investigate the effects of aluminum sulfate administration on the brain tissues of old rats, when given at different concentrations. The experiment attempted to further ascertain whether aluminum exposure cause Alzheimer's disease. Seventy-five aged Sprague-Dawley rats were divided into five groups; a control group, 2 ppm aluminum sulfate group, 20 ppm aluminum sulfate group, 40 ppm aluminum sulfate group, and 200 ppm aluminum sulfate group, and were kept on the respective diets for 12 weeks. In order to understand the influence of aluminum on the brain, serum aluminum concentrations, phospholipid composition, and catecholamine concentrations were compared between the aluminum-treated groups and the normal group. According to the results, serum aluminum was higher in the aluminum sulfate-treated groups than in the normal group. Within the cortex, catecholamine concentrationes were significantly increased but cerebellum and brainstem tissue were significantly decreased, in the aluminum sulfate-treated groups compared to the normal group. For phospholipid composition, phosphatidyl inositol was significantly increased wherase phosphatidyl choline, phosphatidyl ethanolamine, and phosphatidyl serine were significantly decreased in the aluminum sulfate-treated groups versus the normal group. Based on the data, increased aluminum consumption in experimental animals causes increased serum aluminum levels and catecholamine variation. These phenomena are very similar to conditions of Alzherimer's disease. Therfore, the results of this experiment further suggest that aluminum cause Alzherimer's disease, coinciding with reports that aluminum is a cause of neurofibrilly tangles in the brain.

Aluminum nitride (AlN) powders were prepared by the chemical vapor synthesis (CVS) process in the system. Aluminum chloride () as the starting material was gasified in the heating chamber of . Aluminum chloride gas transported to the furnace in atmosphere at the gas flow rate of 200-400ml/min. For samples synthesized between 700 and , the XRD peaks corresponding to AlN were comparatively sharp and also showed an improvement of crystallinity with increasing the reaction temperature. In additions, the average particle size of the AlN powders decreased from 250 to 40 nm, as the reaction temperature increased.

  Surface roughness is an important factor to evaluate machined parts in precision machining. This is the major measure of surface quality. This research sets up experiments to select the factors which affect surface roughness in the machining of inclined

Aluminum alloys are not only lightweight materials, but also have excellent thermal conductivity, electrical conductivity and workability, hence, they are widely used in industry. It is important to control and enhance the densification behavior of metal powders of aluminum. Investigation on the extrusion processing combined with equal channel angular pressing for densification of aluminum powders was performed in order to develop a continuous production process. The continuous processing achieved high effective strain and full relative density at . Optimum processing conditions were suggested for good mechanical properties. The results of this simulation helped to understand the distribution of relative density and effective strain.

온실보온을 위한 알루미늄반사단열재의 설치위치와 광택부의 설치방향에 따라 보온효과를 구명하고자 알루미늄반사재와 부직포를 조합하여 모듈을 구성하고, 모듈내 가열량을 각각 100W, 40W로 하여 2차에 걸쳐 처리 건구온도와 흑구온도, 상대습도를 재료의 조합에 따라 분석하였다. 1. 알루미늄반사재가 있는 경우가 부직포만 있는 경우보다 보온효율이 높았으며, 알루미늄을 두 층으로 하면 한 층으로 할 때보다 내부온도가 높았다. 알루미늄반사재를 한 층으로 설치할 때는 알루미늄반사재의 광택부분을 외부로 향하게 하는 것이 내부로 향하게 하는 것보다 모듈내 온도가 높았다. 알루미늄반사재를 두 층으로 할 때는 같은 방향으로 하는 것이 높게 나타났으며 이 경우 광택부를 둘 다 외향으로 배치하는 것이 보온효율이 더 높게 나타났다. 외기온도에 따라 모듈내 건구온도는 전 모듈에서 서서히 상승하며 그 변화의 크기는 외기온도의 변화보다 적었다. 2. 모듈내를 가열하지 않는 경우 모듈내 온도는 모듈간 온도차가 0.5℃를 넘지 않았으며 그 차이를 인정하기 어려웠다. 3. 모듈내의 흑구온도변화는 건구온도변화와 그 경향이 비슷하였다 흑구온도는 대체적으로 건구온도보다 높았으며, 그 경향은 알루미늄반사재광택부가 내향인 경우가 외향인 경우보다 더 강하게 나타났던 바 복사열영향이 큰 것으로 판단되었다. 모듈내 상대습도는 건구온도가 증가하면 비교적 직선적으로 하강하였다.

알루미늄 분말야금부품은 철계 분말부품에 비해 가볍고 알루미늄 주조부품에 비해 우수한 기계적 물성을 갖는다. 단, 상대적으로 비싼 가격이 이 부품의 응용을 제약하는 장벽이었으나 최근의 환경과 에너지 문제에 대한 세계적인 관심은 이를 극복할 수 있는 계기를 제공하고 있다. 선진국은 이미 일본을 중심으로 1990년대부터 알루미늄 분말부품에 대한 기술개발을 진행하였고 현재는 다양한 상용 부품을 판매하고 있으며 조만간 그 판매량이 크게 증가할 것으로 예상된다.

Both photoluminescence and thermal characteristics for SrAl2O4:Eu+2,Dy+3 phosphors synthesizedwith various aluminum compounds (α-Al2O3, γ-Al2O3, amorphous-Al2O3 and Al(OH)3) were investigated in thisstudy. The formation temperature of the host SrAl2O4 crystal is changed by these various aluminumcompounds, as a result of the different thermal decomposition temperature of SrCO3 phase. Among thesecompounds, the amorphous-Al2O3 phase shows the lowest formation temperature of the host SrAl2O4 crystal.The PL emission and excitation spectra of SrAl2O4:Eu+2, Dy+3 phosphor are not affected by these aluminumcompounds. After the removal of the Xenon lamp excitation (360nm), however, the excellent long-phosphorescent property of the phosphor is obtained by the amorphous-Al2O3 phase, although the decay timefor all phosphors decrease exponentially.

Recent studies have revealed the poisonous nature of aluminum(III) species to aquatic and terrestrial organisms. Therefore, this investigation aims to develop batch adsorption experiments in the laboratory, aiming to the removal of aluminum(III) from aqueous solutions onto powdered activated carbon (PAC). The latter (which is an effective and inexpensive sorbent) was prepared from olive stones generated as plant wastes and modified with an aqueous modifying oxidizing agent, viz. HNO3. The main parameters (i.e. initial solution pH, sorbent and Al3+ ions concentrations, stirring times and temperature) influencing the sorption process were examined. The results obtained revealed that the sorption of Al3+ ions onto PAC is endothermic in nature and follows first-order kinetics. The adsorption data were well described by the Langmuir, Freundlich and Dubinin-Radushkevich (D-R) adsorption models over the concentration range studied. Under the optimum experimental conditions employed, the removal of ca. 100% Al3+ ions in the concentration range 1.35-2.75 mg·l-1 was attained. Moreover, the procedure was successfully applied to the recovery of aluminum spiked to some environmental water samples with an RSD (%), does not exceed 1.22%.

Aluminum nitride (AlN) nanopowders with low degree of agglomeration and uniform particle size were synthesized by carbothermal reduction of alumina and subsequent direct nitridization. Boehmite powder was homogeneously admixed with carbon black nanopowders by ball milling. The powder mixture was treated under ammonia atmosphere to synthesize AlN powder at lour temperature. The effect of process variables such as boehmite/carbon black powder ratio, reaction temperature and reaction time on the synthesis of AlN nanopowder was investigated.

The type, volume fraction, size, shape and arrangement of embedded particles influence the mechanical properties of the particle reinforced metal matrix composites. This presents the investigation of the SiC particle and porosity distributions in various aluminum matrix composites produced by cold- and hot-pressing. The microstructures were characterized by optical microscopy and stereological parameters. SiC and porosity volume fractions, and the anisotropy distribution function were measured to establish the influence of the consolidation method.