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61.
This research aims to convert tetraethylene pentamine Gemini surfactants from oil to water-soluble corrosion inhibitors for applying in oil field at temperatures up to 65?°C. To achieve this aim, four new ethoxylated Gemini surfactants denoted as (T1, T2, T4 and T6) bearing different ethylene oxide units of 19, 28, 45 and 65, respectively were prepared and evaluated as corrosion inhibitors. The chemical structures of the prepared inhibitors were verified using FT-IR and 1H NMR spectroscopic analysis. The performance of the prepared surfactants was determined using surface tension measurements and thermodynamic parameters. Weight loss and electrochemical measurements were utilized to measure their corrosion inhibition efficiencies at a temperature range of 25–65?°C. Through the obtained results, the maximum inhibition efficiency of 95.74% was obtained by T6 at 25?°C in 1?M HCl. 相似文献
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Hatem A. Abdel-Aziz Wagdy M. Eldehna Mohamed Fares Sara T. A. Al-Rashood Khalid A. Al-Rashood Marwa M. Abdel-Aziz Dalia H. Soliman 《International journal of molecular sciences》2015,16(4):8719-8743
In continuation of our endeavor towards the development of potent and effective antimicrobial agents, three series of halophenyl bis-hydrazones (14a–n, 16a–d, 17a and 17b) were synthesized and evaluated for their potential antibacterial, antifungal and antimycobacterial activities. These efforts led to the identification of five molecules 14c, 14g, 16b, 17a and 17b (MIC range from 0.12 to 7.81 μg/mL) with broad antimicrobial activity against Mycobacterium tuberculosis; Aspergillus fumigates; Gram positive bacteria, Staphylococcus aureus, Streptococcus pneumonia, and Bacillis subtilis; and Gram negative bacteria, Salmonella typhimurium, Klebsiella pneumonia, and Escherichia coli. Three of the most active compounds, 16b, 17a and 17b, were also devoid of apparent cytotoxicity to lung cancer cell line A549. Amphotericin B and ciprofloxacin were used as references for antifungal and antibacterial screening, while isoniazid and pyrazinamide were used as references for antimycobacterial activity. Furthermore, three Quantitative Structure Activity Relationship (QSAR) models were built to explore the structural requirements controlling the different activities of the prepared bis-hydrazones. 相似文献
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New Approach to Compare Glare and Light Characteristics of Conventional and Balloon Lighting Systems
With the increasing needs to adopt nighttime construction strategies in order to avoid disruption of traffic flow, state agencies are currently experimenting with a new class of light towers known as balloon lights. Compared to regular lighting tower, balloon lights have been reported to reduce glare significantly and to provide more uniform lighting conditions at the site. The objective of this study was to measure light and glare characteristics of two balloon lighting systems in the field. Glare and lighting characteristics of this new class of light towers were compared to a conventional lighting system. For this purpose, field measurements were made of the pavement luminance and the horizontal and vertical illuminances on a predefined experimental grid. Results of this study indicated that while being comparable in terms of wattage and luminous flux, the tested balloon light systems differed in terms of light and glare characteristics. In addition, while conventional light tower provided greater illuminance at the light source than balloon lights, the disability glare was greater for conventional light tower than balloon lights when mounted at the same height. Results of this study revealed that optimum conditions should be sought in the work zone, through which adequate lighting conditions are provided for workers while disability glare is kept below a safe threshold for drive-by motorists. Plotting the maximum veiling luminance ratio (disability glare) against the workable distance provides a simple approach to consider the two factors concurrently in the design of work zone lighting. 相似文献
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El-Khamy Said E. Korany Noha O. El-Sherif Marwa H. 《Multimedia Tools and Applications》2017,76(22):24091-24106
Multimedia Tools and Applications - Steganography is the technique of hiding any secret information like text, image or video behind a cover file. Audio steganography is one of the widespread data... 相似文献
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Fungal applications in sustainable environmental biotechnology 总被引:1,自引:0,他引:1
Marwa T. A. Abdel-Wareth 《The International journal of environmental studies》2017,74(6):1049-1050
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Marwa Ahmed Sallam Adel Mohamed Motawaa Sana Mohamed Mortada 《Drug development and industrial pharmacy》2015,41(1):141-147
Diflunisal is a NSAID used in acute and long term management of pain and inflammation associated with osteoarthritis, rheumatoid arthritis and symptoms of primary dysmenorrhea. However, its oral use is associated with side effects such as peptic ulceration, dyspepsia, gastrointestinal disturbances and bleeding. The aim of this work was to develop lecithin organogels (LO) transdermal delivery system for diflunisal and to study its human skin penetration ability in comparison with an optimized microemulsion-based hydrogel. Ternary phase diagrams were constructed using butyl lactate as an organic solvent and two commercial grades of lecithin. The formation of gel phase was lecithin concentration dependent with Phosholipion 85?G being capable of forming organogels at lower lecithin concentration than Lipoid S75. The gels prepared using butyl lactate were able to tolerate higher amounts of water than could be incorporated in the lipogels prepared with other organic solvents. All the investigated gels possessed acceptable physical properties and were able to deliver diflunisal through human skin. The lipogels delivered higher total drug amount through the skin than the hydrogel. The composition of lecithin seemed to have some effect on the skin permeability enhancement ability of the lipogel. Lecithin containing higher amount of phosphatidyl ethanolamine could provide better transdermal delivery. The elaborated lecithin organogels are potential carriers that create a good opportunity for transdermal delivery of diflunisal overcoming the side effects associating its oral route. 相似文献