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101.
A simple, one-step slurry coating technique was used to aluminize open cell nickel metal foam at low temperature and short hold-down time. Three slurries of different composition, heat-treated at 650 °C for 2 h, were used to investigate the possibility of developing an aluminide coating on a commercially produced Ni foam. In all cases a dense, well-adhered to the Ni substrate aluminide coating of several μm thickness was produced. The thickness and aluminide phase and composition (NiAl and/or Ni3Al) of the coating strongly depend on Al content and the mix of activators in the slurry. 相似文献
102.
Ouardia Zamoume Sophie Thibault Gwenaël Regnié Med Omar Mecherri Marina Fiallo Patrick Sharrock 《Materials science & engineering. C, Materials for biological applications》2011,31(7):1352-1356
Limited blood circulation to the skeletal tissue is a major cause of reduced therapeutic effects seen with drugs administered by conventional systemic ways. To resolve this issue and obtain a sufficiently high local concentration to induce therapeutic effects, several implanted drug delivery systems have been developed for hard tissues using biomaterials.We have designed a drug delivery device based on hydroxylapatite (HA) and tested it in vitro using metronidazol and chloramphenicol as model compounds. Porous HA ceramics were prepared with two different shapes (cylindrical and spherical). Known amounts of drugs were introduced inside a drilled hole and sealed with wax. The ceramics were then suspended in stirred distilled water in closed polypropylene vials. Drug release was observed during several weeks.A mathematical model used to describe drug release from HA was elaborated based on the expressions of Fick's laws. The experimental kinetic results could be related to ceramic constitution and to drug localization. 相似文献
103.
Kamel Eddine El Mecherfi Djamel Saidi Omar Kheroua Ghazalia Boudraa Mahmoud Touhami Olivier Rouaud S��bastien Curet Yvan Choiset Hanitra Rabesona Jean-Marc Chobert Thomas Haertl�� 《European Food Research and Technology》2011,233(5):859-867
Effect of combined microwave (MW) and enzymatic hydrolysis on the human immunoglobulin E (IgE)-binding properties of ??-lactoglobulin (??-lg) and other whey proteins (WP) was investigated. Separated ??-lg and full whey protein isolate (WPI) were hydrolyzed with trypsin, chymotrypsin, mixture of trypsin/chymotrypsin, and pepsin at three microwave power levels: 50?W during 1 and 5?min, 100 and 200?W during 1 and 3?min. The immunoreactivity of the obtained hydrolysates resulting from combined microwave protease treatment was assessed using sera of young patients allergic to bovine whey proteins. The application of microwave treatment at 200?W enhances the hydrolysis of ??-lg by pepsin in 3?min and decreases significantly its immunoreactivity. The extensive hydrolysis of the microwave-treated ??-lg and WPI with trypsin, chymotrypsin, and the mixture of trypsin with chymotrypsin did not have an impact on the IgE binding of the products obtained in all the studied conditions. 相似文献
104.
This article presents solar energy or specifically the solar photovoltaic (PV) development outlook in Malaysia. The paper first introduces the massive potential of solar energy in the country, the key players in the solar energy development and the early solar energy policies, and programmes in the country. The most important to the PV development is the Malaysia Building Integrated Photovoltaic initiative, which is presented in this paper followed by an explanation on the Feed-in Tariff recently introduced in the country to encourage new solar PV projects. The outlook for solar PV in Malaysia is optimistic and as the uptake of solar PV increases, the unit cost is coming down rapidly. Solar PV is expected to be the most competitive Renewable Energy (RE) source, with the potential to achieve grid parity for electrical power in the country in the near future, and surpassing all other REs combined by 2050. 相似文献
105.
A Al-Othman S Al-Musharaf NM Al-Daghri S Yakout KM Alkharfy Y Al-Saleh OS Al-Attas MS Alokail O Moharram S Sabico S Kumar GP Chrousos 《Nutrition journal》2012,11(1):56
ABSTRACT: BACKGROUND: Coffee and tea consumption was hypothesized to interact with variants of vitamin D-receptor polymorphisms, but limited evidence exists. Here we determine for the first time whether increased coffee and tea consumption affects circulating levels of 25-hydroxyvitamin D in a cohort of Saudi adolescents. METHODS: A total of 330 randomly selected Saudi adolescents were included. Anthropometrics were recorded and fasting blood samples were analyzed for routine analysis of fasting glucose, lipid levels, calcium, albumin and phosphorous. Frequency of coffee and tea intake was noted. 25-hydroxyvitamin D levels were measured using enzyme-linked immunosorbent assays. RESULTS: Improved lipid profiles were observed in both boys and girls, as demonstrated by increased levels of HDL-cholesterol, even after controlling for age and BMI, among those consuming 9--12 cups of coffee/week. Vitamin D levels were significantly highest among those consuming 9--12 cups of tea/week in all subjects (p-value 0.009) independent of age, gender, BMI, physical activity and sun exposure. CONCLUSION: This study suggests a link between tea consumption and vitamin D levels in a cohort of Saudi adolescents, independent of age, BMI, gender, physical activity and sun exposure. These findings should be confirmed prospectively. 相似文献
106.
A.M.T. Omar M.S. Hamed M. Shoukri 《International Journal of Heat and Mass Transfer》2009,52(23-24):5557-5566
A model using an analytical/empirical approach has been developed to predict the rate of heat transfer in the stagnation region of a planar jet impinging on a horizontal flat surface. The model has been developed based on the hypothesis that bubble-induced mixing would result in enhanced or additional diffusivity. The additional diffusivity has been included in the diffusion term of the conservation equations. The value of the effective diffusivity has been correlated with jet parameters (velocity and temperature) and surface temperature using experimental data. The important aspects of the bubble dynamics (generation frequency and average bubble diameter) have been acquired using high-speed imaging and an intrusive optical probe. The applicability of the proposed model has been investigated under conditions of partial and fully-developed nucleate boiling. Experiments have been carried out using water at atmospheric pressure, mass flux in the range of 388–1649 kg/m2 s, degree of sub-cooling in the range of 10–28 °C, and surface temperature in the range of 75–120 °C. Results showed that the proposed model is able to predict the surface heat flux with reasonable accuracy (+30% and ?15%). 相似文献
107.
This paper discusses an experimental scenario for an e-health monitoring system (EHMS) that uses a service-oriented architecture (SOA) as a model for deploying discovering, integrating, implementing, managing, and invoking e-health services. Such a model could help the healthcare industry to develop cost efficient and dependable healthcare services. 相似文献
108.
HO Ammar M Ghorab SA el-Nahhas SM Omar MM Ghorab 《Canadian Metallurgical Quarterly》1995,50(12):805-808
This study is a retrospective review of admissions, discharge records and blood culture results of neonates admitted to the Neonatal Intensive Care Unit of Korle Bu Teaching Hospital in Accra, from the first of January 1991 to the 31st of December 1992. During this two year period there were 443 positive blood cultures. Ninety percent of the blood cultures were from babies born in Korle Bu Teaching Hospital, thus making the incidence of neonatal bacteraemia 22.2 per 1000 live births. The overall mortality rate was 37.2%. Gram negative bacteria accounted for 70.9% and Gram positive bacteria for 29.1% of all neonatal bacteraemia. The most common isolates were Enterobacter species 29.6%; Streptococcus faecalis 14.4%; Staphylococcus aureus 10.8%; Acinetobacter species 9.5%; Klebsiella species 9% and Escherichia coli 8.8%. It is concluded that the incidence of neonatal bacterial sepsis is high in our hospital and is associated with a very high mortality rate. There is thus an urgent need to institute appropriate preventive and therapeutic measures. 相似文献
109.
Whey was employed as a reconstituting medium for dried milk used for cheese making.Ras cheese was made from fresh milk; whey was collected and dried skim milk was used to prepare a reconstituted milk with 20% total solids. Ras cheese was made from it and this process was repeated a further three times.The addition of whey was beneficial in reducing, by 50%, the time necessary to raise the acidity of milk to make it suitable for rennet action. The time necessary to make it suitable for whey removal was also reduced by 50%. Consequently, the time required for pressing was only 8 h, instead of 16 h. Generally, the use of whey is considered to be a better process for Ras cheese making. In addition to the utilisation of whey, it produced a good and acceptable cheese. The cheese was manufactured within a shorter time than cheese made with fresh milk. 相似文献
110.
G. E. M. Moussa M. T. Omar 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1970,20(9):285-286
Measurements of the rate of reduction of chromium(VI) oxide in acetic acid–acetic anhydride solution by 2-methyl-pentane, 3-methylpentane, 2,3-dimethylbutane and 2,4-dimethylpentane show that the initial rate depends on the number and nature of carbon atoms in the hydrocarbon. When steric or other interaction effects prevail between adjacent atoms or groups in the molecule, these effects also influence the rate. The values obtained for the oxidation rates agree with those calculated from a proposed expression (Rnp+R'ns+R'nt)/(np+ns+nt) based on the formula of Chambers & Ubbelohde. 相似文献