• Asian Pacific Journal of Cancer Prevention
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• v.15 no.24
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• pp.10861-10865
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• 2015

Background: Oral cancer is in increasing in incidence in Yemen and indeed worldwide. Knowledge regarding risk factors and early signs in the general population can help in prevention and early detection of the disease. Purpose: The aim of this study was to assess the level of awareness and knowledge of oral cancer in the general population in Yemen. Materials and Methods: A cross-sectional survey using a self-administered questionnaire was conducted on Yemeni adults aged ${\geq}15$ years old. A total of 543 persons participated, the collected data being analyzed using SPSS software. The significance level was set at p<0.05. Results: Two thirds (71.5%) of the participants had heard about oral cancer. Smoking and smokeless tobacco usage were identified as the major risk factors by 71.5% and 73.7% of the participants, respectively. Only 24.1% and 21.4%, respectively, were able to correctly identify red and white lesions as early signs of oral cancer. Knowledge of oral cancer was significantly associated with age (p<0.01), gender (p<0.05) and education level (p<0.001). Conclusions: The findings suggest that the knowledge regarding oral cancer in this population is low. Therefore, educational programs are highly needed to improve such knowledge.

• Transactions of the Korean hydrogen and new energy society
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• v.21 no.5
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• pp.390-397
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• 2010

0.5wt% Ru/$\alpha-Al_2O_3$ catalysts are prepared by deposition-precipitation method for the preferential CO oxidation In order to investigate the effect of pH on the Ru dispersion and particle size, the pH of precursor solution is adjusted to between 5.5 and 9.5. 0.5wt% Ru/$\alpha-Al_2O_3$ catalyst prepared at the pH of 6.5 has high Ru dispersion of 17.9% and small particle size of 7.7nm. In addition, 0.5wt% Ru/$\alpha-Al_2O_3$ catalyst prepared at the pH 6.5 is easily reduced at low temperatures below $150^{\circ}C$ due to high dispersion of $RuO_2$ particle and shows high CO conversion over 90% in the wide temperature range between $100^{\circ}C$ and $160^{\circ}C$. Moreover, the deposition-precipitation is a feasible method to improve the Ru dispersion as compared to the impregnation method. The 0.5wt% Ru/$\alpha-Al_2O_3$ catalyst prepared by deposition-precipitation exhibits higher CO conversion than 0.5wt% Ru/$\alpha-Al_2O_3$ catalysts prepared by impregnation due to higher metal dispersion and better reducibility at low temperature.

• Journal of Life Science
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• v.7 no.4
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• pp.361-370
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• 1997

Sprague-Dawley male rats were fed experimental diet, and also were orally daministerred with 3.0% ultra low viscosity (ULV) sodium alginate-added functional drink(AL-3.0% group : HAEJOMIN), 5.0% polyedxtrose(PD)-added drink(PD-5.0group) and 2.5% polydextrose-added drink(PD-2.5 group) for 8 weeks. Effect of rhese dietary fiber-added functional drinks on body weight, feed and gross efficincies, triglyceride and cholesterol levels, LDL- cholesterol levels, hydroxyl radical and malondialdehyde levels, and superoxide dismutase (SOD) activity in serum of SD rats were evaluated. Administration of AL-3.0 drink and PD-5.0 drink resulted in a marked inhibition in increase of body weight compared with control and PD-2.5 groups for 8 weeks. Inhibition effect in body weight in 3.0% alginic acid-added drink )AL-3.0 froup_ showed a same trend in 5.0% polydextrose(PD)-added drink (PD-5.0 group)(p<0.001). Therefore, it is found that inhibition effects of obesity in 3.0% alginic acid-added drink were higher 2 times than that in same concentration of polydextrose(PD)-added drink. Triglyceride and cholesterol levels in AL-3.0 and PD-5.0 groups significantly decreased to 25$\sim$30% compared with control group(p<0.01$\sim$0.001), but there were no significant differences in these drinks. LDL-cholesterol levels in AL-3.0 group significantly decreased about 15% compared with PD-5.0 group, but atherogenic index in AL-3, 0 group showed a similar trend to that in PD-5.0 group. Hydroxyl radical formations and lipid peroxide(LPO) levels in AL-3, 0 and PD-5.0 groups significantly decreased to 15% and 20%, respectively, compared with control group(p, 0.05$\sim$0.01), but there were no significant differences in these drinks. Superoxide, dismutase(SOD) activity in AL-3.0 group significantly higher (about 255) than those in control and PD-5.0 groups(p<0.01). These results suggest that administration of ULV-sodium alginate-added functional drink(HAEJOMIIN) effectively can not only inhibit obesity, but also can intervent chronic degenerative disease and aging process.

• Resources Recycling
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• v.20 no.2
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• pp.54-59
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• 2011

An investigation on the synthesis of aluminum tartrate, one of the aluminum organic compounds, has been performed using aluminum chloride solution as a raw material. For this aim, the effect of the ratio of ethanol/Al solution and pH on the synthesis of aluminum tartrate has been examined and aluminum tartrate synthesized has also been characterized in terms of the chemical composition, X-ray diffraction pattern, particle size distribution, and SEM analysis. As a result, the synthesis more than 97% could be obtained under the conditions of pH more than 3.0 at the ratio of ethanol/Al solution of 3.0. From the chemical analysis of aluminum tartrate synthesized in this work, the content of $NH_4$, Al and C was found to be 9.10, 4.83 and 25.8%, respectively. In addition, aluminum tartrate synthesized from the aluminum chloride solution was found to be $(NH_4)_3Al(C_4H_4O_6)_3$.

• Metals and materials international
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• v.24 no.6
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• pp.1256-1261
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• 2018

Both thermoplastic formability and electrical conductivity of Al-Ni-Y metallic glass with 12 different compositions have been investigated in the present study with an aim to apply as a functional material, i.e. as a binder of Ag powders in Ag paste for silicon solar cell. The thermoplastic formability is basically influenced by thermal stability and fragility of supercooled liquid which can be reflected by the temperature range for the supercooled liquid region (${\Delta}T_x$) and the difference in specific heat between the frozen glass state and the supercooled liquid state (${\Delta}C_p$). The measured ${\Delta}T_x$ and ${\Delta}C_p$ values show a strong composition dependence. However, the composition showing the highest ${\Delta}T_x$ and ${\Delta}C_p$ does not correspond to the composition with the highest amount of Ni and Y. It is considered that higher ${\Delta}T_x$ and ${\Delta}C_p$ may be related to enhancement of icosahedral SRO near $T_g$ during cooling. On the other hand, electrical resistivity varies with the change of Al contents as well as with the change of the volume fraction of each phase after crystallization. The composition range with the optimum combination of thermoplastic formability and electrical conductivity in Al-Ni-Y system located inside the composition triangle whose vertices compositions are $Al_{87}Ni_3Y_{10}$, $Al_{85}Ni_5Y_{10}$, and $Al_{86}Ni_5Y_9$.

• Journal of the Korean Wood Science and Technology
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• v.14 no.2
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• pp.29-35
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• 1986

This study was carried out to examine the effect of aluminium sulfate addition to the alkali-acid catalyst phenolic resin for the manufacture of the kapur (Dryobalanops spp.) plywood on the reduction of phenolic resin spreading. On the manufacture of plywood, Adhesive Contents such as 50g/$m^2$, 75g/$m^2$ and 150g/$m^2$ were treated. The spreading adhesive content of 50g/$m^2$ and 75g/$m^2$ had been controlled to about 150g/$m^2$ added with the water in order to get sufficient spreading and controlled to pH 4.5 with aluminium sulfate [$Al_2(SO_4)_3$]. The results are summarized as follows: 1. Specific gravities of air dried plywood manufactured from each adhesive ranged from 0.77 to 0.86 and their moisture contents met the KS requirements. 2. In dry and wet shear strengths, 150 $P_{Al{\cdot}Ac}$ adhesive showed the highest and 75 $P_{Al{\cdot}Ac{\cdot}Am}$ adhesive indicated higher value than 150 $P_{Al{\cdot}Ac}$ adhesive. 3. In case of glue shear strength after boiling test, 150 $P_{Al{\cdot}Ac}$ adhesive was the best and adding of aluminium sulfate was not effective on reinforcement of boiling water resistance of phenolic resin, but met KS requirements. 4. 75 $P_{Al{\cdot}Ac{\cdot}Am}$ adhesive showed the good shear strength and met KS requirements. Therefore, adding of aluminium sulfate was very efficient for economical plywood manufacture.

• Composites Research
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• v.13 no.6
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• pp.23-29
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• 2000

The internal residual stresses within the multilayered structure with sharp interface induced by the difference in thermal expansion coefficient between the materials of adjacent layers often provide the source of failure such as delamination of interfaces etc. Recent development of the multilayered structure with functionally graded interface would be the solution to prevent this kind of failure. However a systematic thermo-mechanical analysis is needed for the customized structural design of multilayered structure. In this study, theoretical model for the thermo-mechanical analysis is developed for multilayered structures of the $Al-SiC_p$ functionally graded composite for electronic packaging. The evolution of curvature and internal stresses in response to temperature variations is presented for the different combinations of geometry. The resultant analytical solutions are used for the optimal design of the multilayered structures with functionally graded interface as well as with sharp interface.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.166-166
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• 2010

산업 전반에 걸쳐 중요한 광원인 808 nm 대역의 레이저 다이오드 제작에는 현재 InGaAsP/InGaP/GaAs 및 InGaAlAs/GaAs 양자우물을 이용하여 제작되고 있다. 이는 양자우물과 이를 둘러싸는 장벽물질간의 band-offset이 적어 효율적인 고출력 레이저 다이오드의 제작에 어려움이 있기 때문에 강한 캐리어 구속 효과를 지니는 양자점을 사용하는 것이 고출력 레이저 다이오드를 제작할 수 있는 방법이다. 실험에 사용된 InAlAs 양자점은 Riber사의 compact21 MBE 장치를 사용하여 성장하였으며 GaAs기판을 610도에서 가열하여 표면의 산화층을 제거하고 580도에서 약 100 nm 두께의 GaAs 버퍼층 및 30 nm 두께의 $Al_{0.4}Ga_{0.6}As$층을 성장하였다. GaAs 기판의 온도를 내린 후 migration enhanced epitaxy 방법을 사용하여 InAs 및 AlAs를 번갈아 주입하여 성장하였다. InAlAs 양자점의 성장 중에 InAlAs의 양, 성장 온도, As flux량 및 As 분자 상태 변화 등 다양한 조건을 변화 시켜 샘플을 성장시켰다. 그 결과 기판 온도가 600도이며 As4 flux가 $1\;{\times}\;10^{-6}\;Torr$ 조건하에서 성장한 InAlAs/AlGaAs 양자점이 양질의 808 nm의 파장 대역을 얻을 수 있었다.

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.2
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• pp.195-201
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• 1988

A laboratory experiment was coducted to investigate the relation of various soil phosphorus and some soil chemical properties which affect the composition of inoganic phosphorus and soil phosphorus with 149 phosphorus accumulated soil samples. Soil pH and exchangeable Ca were showed positively high significant correlation with 1.25 $N-NH_4$ OAc-P, Saloid-P, Ca-P and Total-P, however the soil pH was not showed significant relationship with $0.01M-CaCl_2-P$, Al-P, and Fe-P, respectively. Active Al and available phosphorus, water soluble P, and inoganic phosphorus were showed negatively high significant correlation, but Al-P and Fe-P were not. Also active Fe were showed positively significant correlation at 1% level for Fe-P and total-P. In the relationahips between soil pH and active Al, and exchangeable Ca, active Al were showed negatively high significant correlation with log regression equation, and exchangeable Ca were showed positively high significant correlation with liner regression equation. P sorbed by soil from p 20ppm solution was showed negatively high significant correlation with available phosphorus, water soluble P and $0.01M-CaCl_2-P$ in soil and positively with active Al, but was not significant with Ca-P.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.14 no.6
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• pp.277-280
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• 2004

p-ZnO films have been grown on (0001) sapphire substrates by RF-DC magnetron co-sputtering. The p-ZnO single crystalline thin films of the thickness about 120 nm were grown successfully. The dopant (Aluminum) was sputtered simultaneously from Al metal target by DC sputtering during rf-magnetron sputtering of ZnO at the substrate temperatures of $400^{\circ}C$ and $600^{\circ}C$ respectively. The crystallinity and optical properties of as-grown P-ZnO films have been characterized.