• Clean Technology
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• v.15 no.1
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• pp.38-41
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• 2009

Red mud is generated as a waste byproduct during the production of aluminum hydroxide/alumina from bauxite ore in the Bayer process. In this study coagulants for wastewater treatment were prepared by leaching iron and aluminum from red mud with hydrochloric acid. The removal efficiency of heavy metal ions by the red mud coagulant increased with increasing the adjusted pH value of the synthetic wastewater. When the red mud coagulant was prepared, the leaching efficiency of Fe decreased with increasing the weight of red mud, while the pH value of the red mud coagulant increased. The solution of the red mud coagulant mixed with water was reacted again with red mud to produce the leached solution, which had higher concentrations of Fe and Al and a higher pH value than the red mud coagulant. Also, its pH value was comparable to that of other coagulants: $FeCl_3$ and $Fe_2(SO_4)_3$.

• Journal of the Korean Ceramic Society
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• v.25 no.5
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• pp.465-472
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• 1988

Alpha alumina powder with fine particle size and narrow particle size distribution was prepared by precipitation method using Al2(SO4)3.18H2O as a starting material. The alpha alumina powder was prepared by calcining aluminum hydroxide which was formed under various pH values. The sinterabilityof alpha alumina powder and the effect of MgO on the sinterability of alpha alumina powder were investigated. The sinterability of alpha alumina powder was the order of pH=10≒pH11>pH=7≒pH9, and alpha alumina obtained from boehmite which was prepared by precipitation method reached to 97.5% of theoretcal density by the pressureless sintering. The effect of MgO on volume shrinkage of alumina was very slight in the initial sintering stage but remarkable in the final sintering stage. It was also found that MgO controlled effectively the grain growth of alumina.

• Journal of the Korean Ceramic Society
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• v.28 no.6
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• pp.465-470
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• 1991

AlN powder was synthesized by carbothermal reduction and nitridation of aluminum hydroxides precipitated in 5∼11 pH range from Al2(SO4)3$.$18H2O aqueous solution. Nitridation reactivity of hydroxide, which depends on precipitation pH, reaction temperature and time, was examined by XRD analysis at 1200∼1350$^{\circ}C$ and compared with that of commercial ${\alpha}$-Al2O3. Hydroxides obtained at higher pH could be more easily nitridated and, considering DTA/TG and BET results, the reason seems to be specific surface area difference of reactants depending on the content of decomposed structural water and the transition rate from transition-Al2O3 to ${\alpha}$-Al2O3.

• KIEAE Journal
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• v.7 no.4
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• pp.135-140
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• 2007

In this study we settled the trouble of the MgO board of existence by this research. We changed the wooden one of the main ingredient of a board to a perlite and a mineral particle in the aluminum hydroxide group and proceeded with a study to physical character and fire resistance efficiency improvement. The result yellowing phenomenon could be improved and it was possible to reduce size decrease of pin hole and the frequency of occurrence. We found out that the in case of absorbed amount added 5~8% corresponding to the weight decreases the acrylic group emulsion suddenly. So this product is improved with the bending strength and water-resistance. After behavior stop time measurement of a mouse for experiments was measured at the time of a gas harmful effect test, an improved MgO board appeared more highly for an average of 138 seconds compared with a board of existence.

• Biomolecules & Therapeutics
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• v.4 no.4
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• pp.334-338
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• 1996

Antigenicity of DA-3285, human recombinant erythropoietin which was produced from mammalian cells, was examined in guinea pigs and mice. In active systemic anaphylactic test, mild anaphylactic signs were observed in guinea pigs sensitized subcutaneously with DA-3285 or DA-3285 incorporated with complete Freund's adjuvant(CFA) when challenged with high dose(1000 IU/Kg) of DA-3285. Other groups showed negative responses. In mouse-rat passive cutaneous anaphylaxis test, 20% sera of mice immunized with DA-3285 or DA-3285 mixed with aluminum hydroxide(alum) showed mild positive responses. In the case of indirect haemagglutination reaction(IHA) test, when sheep red blood cells coated with DA-3285 was incubated with mouse serum, all the serum samples were showed negative responses. These results suggest that DA-3285 has a very weak antigenic potential and probably would not induce systemic allergic reactions in clinical uses.

• YAKHAK HOEJI
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• v.45 no.1
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• pp.23-28
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• 2001

Hydrotalcite was prepared by reacting with sodium carbonate, magnesium hydroxide and aluminum chloride solutions in this study. The optimum synthesis conditions based on the yield of the product were established by applying Box-Wilson experimental design. It was found that the optimum synthesis conditions of hydrotalcite were as follows ; reacting temperature : 63~9$0^{\circ}C$, concentration of reactant solution : 18.20~19.82%, molar concentration ratio of two reactants [Mg(OH)$_2$] / (AICl$_3$.6$H_2O$) : 6.0, temperature of washing water : 29.0-34.4$^{\circ}C$, drying temperature : 56-77.6$^{\circ}C$. The physicochemical properties of hydrotalcite as medicine were studied by use of chemical analysis, bulk volume test and acid consuming capacity measurements.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.481-484
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• 2005

Recently, Since the advanced nano technology develops unique physical and chemical properties different from those of the conventional materials. Normal concretes mixed with nano size materials have been studied to improve the fire-resistance with high strength and lower heat conductivity. In this pilot study, the nano-particle contents in the specimens ($\Phi$10\times20 cm$) were 0, 2, 4, and 6$\%$ by weight of cement, and fire-temperatures 800$^{circ}C$ was considered. The results show that as the nano-particle contents increases, fire resistance of concrete are superior to those of the ordinary concrete. Also, the experimental results show that fire resistance of nano Aluminum hydroxide dispersed concrete are superior to those of the nano-SiO2 concrete.

• Journal of the Korean Ceramic Society
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• v.13 no.4
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• pp.25-35
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• 1976

Mullite was synthesized by using kaolin and $\alpha$-alumina, and halloysite and aluminum hydroxide as raw materials at the various temperature in the range of 1200$^{\circ}$-1750$^{\circ}$C. The degree of mullitization was measured respectively by a quantitative X-ray diffraction method and a chemical analysis method. The rate and the maximum degree of mullitization were found to increase with temperature . The reaction completed at 1600$^{\circ}$Cfor less than 30 minutes, and yielded 98% mulllite inpurity in the case of kaolin-Al(OH)3. TiO$_2$ up to 3% was added to the batches of kaolin-Al(OH)$_3$. the effect of addition on the mullitization was investigated and found to decrease the sintering temperature for the mullitization. The mechanism of TiO$_2$ addition on the formation of mullite was also discussed.

• Toxicological Research
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• v.9 no.1
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• pp.125-132
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• 1993

Antigenic potential of recombinant human growth hormone (LBD-007), a newly developed drug for growth hormone deficiency, was investigated in mice and guinea pigs. 1. Mice showed production of antibodies against LBD-009 (1.5IU/kg) with aluminum hydroxide gel(alum) as an adjuvant, Judaged by the heterologous anaphylaxis (PCA) test using rats. On the other hand, antibodies against ovalbumin (OVA) inoculated with alum were definitely detected. 2. In the studies with guinea pigs, both the inoculation of LBD-009 (0.15IU/kg-1.5IU/kg) only and of LBD-009 with complete Freund's adjuvant (CFA) as an adjuvant did produce weak positive reactions in homologous passive cutaneous anaphylaxis (PCA). On the other hand, the inoculation of ovalbumin with complete Freund's adjuvant (CFA) produced positive reaction in PCA.

• Biomolecules & Therapeutics
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• v.2 no.2
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• pp.108-113
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• 1994

Toxicity study of recombinant hepatitis B vaccine (LBD-008), a newly developed drug for acute and chronic hepatitis, was investigated in mice and guinea pigs. 1. Mice showed no production of antibodies against LBD-008 inoculated with aluminum hydroxide gel (Alum) as an adjuvant, judged by the heterologous anaphylaxis (PCA) test using rats. On the other hand, antibodies against ovalbumin (OVA) inoculated with alum were definitely detected. 2. In the studies with guinea pigs, both the inoculation of LBD-008 only and of LBD-008 with complete Freund's adjuvant (CFA) as an adjuvant did not produce positive reactions in any of homologous active systemic anaphylaxis (ASA). On the other hand, the inoculation of ovalbumin with complete Freund's adjuvant (CFA) produced positive reaction in both of PCA and ASA. 3. These findings suggested that LBD-008 has no antigenic potential in mice or guinea pigs.