• Toxicological Research
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• 제14권2호
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• pp.163-169
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• 1998

Fluoride (F), over a narrow concentration range, increases bone formation. Aluminum (Ai) too is biphasic in its action on bone, being mitogenic at very low levels and inhibitory at higher levels. Both F and Al are present in finished drinking water where the chemical interaction of these two agents is well characterized. F and AI, given individually, accumulate preferentially in bone. In addition. in vivo studies have shown that F causes the co-accumulation of Al in bone. Thus, it was necessary to determine the interactive effect of these two agents on bone mitogenesis. Calvaria were obtained from neonatal CD-1 mice and cultured with various concentrations of F (0.05~19 ppm) as NaF, Al (2 ppb~2 ppm) as $AlCl_3$ , or F and Al for 3 days at $37^{\circ}C$ on a rotating roller drum. Alkaline phosphatase activity in calvaria and $\beta$-glucuronidase activity in culture medium were determined as a measures of bone turnover. Alkaline phosphatase activity in calvaria was significantly increased by F (0.05~2 ppm) treatment and $\beta$-glucuronidase activity was slightly increased in the culture medium of calvaria treated with 0.3 ppm Al. The combination of 19 ppm F and 0.3 ppm Al increased alkaline phosphatase activity in calvaria, but did not affect $\beta$-glucuronidase activity, suggesting the interactive effect of fluoride and aluminum on bone turnover.

• 한국식품영양과학회지
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• 제25권1호
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• pp.39-45
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• 1996

The study was performed to investigate the effects of administration of aluminum compound in Kidney metabolism and plasma hormone of rats. Seventy frve male Sprague-Dawley strains rats were divided into five groups consisting of the control, 250ppm AlCl$_3$group, 500ppm AlCl$_3$ group, 250ppm $Al_2$(SO$_4$)$_3$group, 500ppm $Al_2$(SO$_4$)$_3$group and kept on the diet for 2 weeks. The body weight gain was increased by the administration of AlCl$_3$ but decreased by the administration of $Al_2$(SO$_4$)$_3$as compared to the control. The urinary excretion of sodium and creatinine were increased and free water clearance and urine volume were decreased significantly after AlCl$_3$adminstration group as compared to the control. The water balance, free water clearance, excretion of sodium and creatinine were increased and the excretion of chlorine was decreased after $Al_2$(SO$_4$)$_3$ administration as compared to the control. Plasma renin activity was increased and plasma aldosterone content was compared to the control. Plasma renin activity was increased and plasma aldosterone content was significantly decreased after adminstration of aluminum compounds as compared to the control.

• 한국가스학회지
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• 제13권4호
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• pp.8-14
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• 2009

하이브리드 촉매를 이용하여 합성가스로부터 디메틸에테르(DME)를 1단계 공정으로 합성하였다. 하이브리드 촉매는 메탄올 합성반응을 위하여 Cu-ZnO-$Al_2O_3$, 메탄올 탈수반응을 위하여 aluminum phosphate 혹은 $H_3PO_4$-modified $\gamma$-alumina로 구성되었다. 제조한 촉매들은 XRD, BET, SEM, FT-IR, $NH_3$-TPD를 이용하여 특성분석을 하였다. XRD 분석을 통해 aluminum phosphate가 잘 합성되었음을 알 수 있었다. BET 분석을 통해 aluminum phosphate의 비표면적이 P/Al의 비에 따라서 달라짐을 확인할 수 있었다. 반응실험 결과 메탄올 탈수 촉매로 사용된 aluminum phosphate의 P/Al의 비가 1.2인 하이브리드 촉매에서 55%의 CO 전환율과 70%의 DME 선택도를 보여 주었다. $\gamma$-alumina를 인산으로 처리한 경우 촉매활성 감소를 막을 수 있었다. 하지만 85%의 진한인산으로 처리한 경우에는 촉매 활성 및 DME 선택도가 낮아짐을 확인할 수 있었다.

• 약학회지
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• 제27권2호
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• pp.139-148
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• 1983

The neutralizing capacities of the antacids, which are frequently used in Korean market, were evaluated in vitro by the methods of Resset and Rice, Fordtran and Collyns, and modified Beekman, respectively. The antacids used in the study are two kinds, the one is preparations from Seoul National University Hospital and the other is products from pharmaceutical companies, and their components are aluminum phosphate, aluminum hydroxide, magnesium aluminum hydroxide, magnesium hydroxide, basic aluminum sucrose sulfate and $2MgO{\times}Al_{2}O_{3}{\times}SiO_{3}$, etc. The hospital preparations, DMC and MAC powders, showed most powerful and sustained neutralizing capacities, i.e. they maintained the pH range from 5 to 8 for 60min, Whereas pharmaceutical products, aluminum hydroxide gel containing magnesium hydroxide and magnesium aluminum hydroxide gel exhibited a moderate capacities, i.e pH ranged from 3 to 6, and aluminum phosphate, $2MgO{\times}Al_{2}O_{3}{\times}SiO_{2}$ and basic aluminum sucrose sulfate displayed a weak activity, pH ranged from 2 to 3. When the therapeutic doses of aluminum hydroxide gel containing magnesium hydroxide and magnesium aluminum hydroxide gel were divided into 2 doses and each dose was used at the interval of 30min., the divided doses kept more prolonged higher pH than the single therapeutic dose. Milliequivalents of neutralizing capacities of each antacid were measured by the method of Fordtran and Collyns. The milliequivalents per 1ml of aluminum hydroxide gel, aluminum hydroxide gel containing magnesium hydroxide, magnesium aluminum hydroxide gel and aluminum phosphate were 2.87, 2.86, 2.57, and 0.67, respectively. The milliequivalents per 100mg of preparations, i.e. MAC powder, dried aluminum hydroxidgel, DMC powder, 2MgO, $Al_{2}O_{3}$. $SiO_{2}$, magnesium aluminum hydroxide and basic aluminum sucrose sulfate were 1.91, 1.68 1.63, 1.45, 1.44, and 0.44, respectively.

• Toxicological Research
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• 제20권3호
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• pp.213-223
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• 2004

This work aimed to study the effectiveness of cellular oxidative parameter (malondial-dehyde, protein carbonyl, and 8-hydroxy-2'deoxyguanosine). The experimental groups were aluminum treated rats and control rats. Aluminum treatd rats were given intraperitoneally aluminum nitrate nonahydrate ($Al^{3+}$, 0.2 mmol/kg) daily for 30 days except Sunday. Control rats were injected 1 ml of saline. After the dose, rats were decapitated and hippocampus and cerebral cortex were removed. The measured parameters were tissue malondialdehyde (MDA, index of lipid peroxidation), protein carbonyl (index of protein oxidation), 8-hydroxy-2'-deoxy-guanosine (8-OHdG, index of DNA oxidation), reduced glutathione (GSH) levels as well as glutathione reductase (GR) and catalase. AI concentrations in the tissues were also measured. All results were corrected by tissue protein levels. The results were as followed; 1. The concentrations of AI in the cortex and hippocampus were significantly higher in the AI-treated rats than in the control rats. 2. Antioxidative enzyme's activity, catalase and GR, were significantly higher in the AI-treated rats than the control rats. GSH levels were also higher in the AI-treated rats. 3. MDA, protein carbonyl, and 8-OHdG concentration of AI-treated rats were significantly higher than those of control rats. 4. The concentrations of antioxidants, and oxidative stress parameter were correlated with the concentrations of AI in hippocampus and cerebral cortex. Catalase and GR activity were also correlated with the concentration of AI. Based on these results, it can be suggested that intraperitoneally injected AI was accumulated in the brain and induced the increase of antioxidant levels and antioxidative enzyme activity. Also, the oxidative products of cellular macromolecules are significantly related to tissue AI concentration. Therefore MDA, protein carbonyl, and 8-OHdG are useful markers for oxidative stress on cellular macromolecules.

• Macromolecular Research
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• 제16권5호
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• pp.441-445
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• 2008

A series of aluminum complexes supported by $\beta$-ketoamino, ligand-bearing, 3-position substituents $LAlEt_2$ ($L=CH_3C(O)C(Cl)=C(CH_3)NAr\;(L_1)$, $L=CH_3C(O)C(H)=C(CH_3)NAr\;(L_2)$, $L=CH_3C(O)C(Ph)=C(CH_3)NAr\;(L_3)$, and $L=CH_3C(O)C(Me)=C(CH_3)NAr\;(L_4)$, $Ar=2,6-^iPr_2C6H_3$) were synthesized in situ and employed in the ring-opening polymerization (ROP) of $\varepsilon$-caprolactone ($\varepsilon$-CL) and cyclohexene oxide (CHO). The 3-position substituents on the $\beta$-ketoamino ligand backbone of the aluminum complexes influenced the catalyst activity remarkably for both ROP of $\varepsilon$-CL and CHO. Aluminum $\beta$-ketoamino complexes displayed different catalytic behavior in ROP of $\varepsilon$-CL and CHO. The order of the catalytic activity of $LAlEt_2$ was $L_1AlEt_2$>$L_2AlEt_2$>$L_3AlEt_2$>$L_4AlEt_2$ for ROP of $\varepsilon$-CL, being opposite to the electron-donating ability of the 3-position substituents on the $\beta$-ketoamino ligand, while the order of the catalytic activity for ROP of CHO was $L_1AlEt_2$>$L_3AlEt_2$>$L_4AlEt_2$>$L_2AlEt_2$. The effects of reaction temperature and time on the ROP were also investigated for both $\varepsilon$-CL and CHO.

• 약학회지
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• 제6권2호
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• pp.13-17
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• 1962

The effects of glycerin and sorbitol and ageing of antacid activity of aluminum hydroxide gel has been described. The results under accelerated temperatures showed sorbitol had excellent stabilizing effect and glycerin had promoting effect by contraries.

• 한국세라믹학회지
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• 제42권4호
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• pp.287-291
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• 2005

나노인덴테이션 시험시의 알루미늄의 팝인 변형에 대하여 연구하였다. 팝인 현상은 알루미늄의 표면 상태에 따라서 발생 유무가 결정되었다. 기계연마한 알루미늄에서는 팝인이 일어나지 않았고, 전해연마한 시편에서만이 팝인이 일어났다. 팝인이 일어나는 경우에는 나노인덴테이션 초기단계에서 탄성변형이 일어났으며 그 후에 갑자기 팝인 변형이 일어났으며 팝인 후에는 탄소성 변형이 일어났다. 전위 활동에 근거한 팝인 발생 메카니즘을 제시하였으며 이는 FIB와 TEM에 의한 미세구조 분석 결과와 일치하였다.

• 한국수소및신에너지학회논문집
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• 제22권1호
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• pp.29-34
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• 2011

This study examined the effect of environmental variables, such as the NaOH concentration and solution temperature, on the rate of hydrogen generation from NaOH solutions through the corrosion of used aluminum cans as a potential candidate material for the safe and economic production of hydrogen. Corrosion of the used aluminum cans was promoted by increasing the NaOH concentration and solution temperature because of the loss of aluminum passivity. The measured rate of hydrogen generation from the NaOH solutions increased with increasing NaOH concentration due to the catalytic activity of NaOH in the hydrolysis process. However, at higher solution temperatures, the rate of hydrogen generation rate was less affected by the NaOH concentration than that at lower temperature.

• 한국초지조사료학회지
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• 제39권4호
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• pp.298-302
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• 2019

Acidic soil significantly reduces crop productivity mainly due to aluminum (Al) toxicity. Alfalfa (Medicago sativa L.) roots were exposed to aluminum stress (Al₃⁺) in calcium chloride (CaCl₂) solution (pH4.5) and root growth, physiological and antioxidant enzyme responses were investigated. The root growth (length) was significantly inhibited after 48 h of aluminum stress imposition. Histochemical staining with hematoxylin indicated significant accumulation of aluminum in Al stress-treated root tissues. Histochemical assay were also performed to detect superoxide anion, hydrogen peroxide and lipid peroxidation, which were found to be more in root tissues treated with higher aluminum concentrations. The enzymatic activity of CAT, POD and GR in root tissues was slightly increased after Al stress treatment. The result suggests that Al stress alters root growth in alfalfa and induces reactive oxygen species (ROS) production, and demonstrates that antioxidant enzymes involved in detoxification of Al-mediated oxidative stress.