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101.
Normawati M. Yunus M.I. Abdul Mutalib Zakaria Man Mohamad Azmi Bustam T. Murugesan 《The Journal of chemical thermodynamics》2010,42(4):491-495
The thermophysical properties of 1-alkylpyridinium bis(trifluoromethylsulfonyl)imide, [Cnpy][Tf2N] ionic liquids where n = 4, 8, 10, or 12 have been determined. Density ρ, and dynamic viscosity η, were determined at T = (293.15 to 353.15) K and refractive index nD, was measured at T = (293.15 to 333.15) K. Empirical correlations are proposed to represent the present experimental results. The values of the coefficient of thermal expansion were calculated from the experimental density values. The thermal decomposition temperature, Td was also determined using thermogravimetric analyzer (TGA) at a heating rate of (10 and 20) K · min?1. 相似文献
102.
Cover Picture: Controlled Synthesis of Nanoporous Nickel Oxide with Two‐Dimensional Shapes through Thermal Decomposition of Metal–Cyanide Hybrid Coordination Polymers (Chem. Eur. J. 9/2015) 下载免费PDF全文
103.
Rana Ahmed Youness Reem Amr Assal Shahira Mohamed Ezzat Mohamed Zakaria Gad Amira Abdel Motaal 《Natural product research》2020,34(10):1475-1480
AbstractThis study focused on studying the impact of flavonoids isolated from Cleome droserifolia on HCC cell lines and to further unveil their possible impact on TP53 and its downstream tumor suppressor miRNAs. Three flavonol glycosides were isolated from C. droserifolia namely, Isorhamnetin-3-O-β-D-glucoside (1), Quercetin-3`-methoxy-3-O-(4``-acetylrhamnoside)-7-O-α-rhamnoside (2), and Kaempferol-4`-methoxy-3,7-O-dirhamnoside (3). They showed a concentration and time dependent reduction in cellular viability and anchorage-independent growth of HCC cells. Moreover, they exhibited a decrease in the migrating capacity of HepG2 cells in a pattern similar to positive control cells. (2) Showed the most potent effects in halting HCC tumorigenic activity (IC50=36?±?1.70?µM) and a repression of the cellular proliferation rate of HepG2 cells. Restoration of TP53 and its downstream tumor suppressor miRNAs; miR-15a, miR-16, miR-34a by (2) was observed. Moreover, attenuation of (2) mediated actions was shown upon using anti-miR-15a and anti-miR-16. To conclude, this study crystallizes a novel role of C. droserifolia in harnessing HCC progression in-vitro with a possible contribution of TP53/miR-15a/miR-16. 相似文献
104.
Mohammadreza Gharibreza John Kuna Raj Ismail Yusoff Zainudin Othman Wan Zakaria Wan Muhamad Tahir Muhammad Aqeel Ashraf 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(3):1715-1730
The Bera Lake basin is a lacustrine mire system and the largest natural lake in Peninsular Malaysia. Three cores were collected from the lake sediments in order to assess sediment quality and ecological risks for aquatic life and human health. An index analysis approach (C f , C d , E r , and IR) and fallout 210Pb and 137Cs radioisotopes were applied to assess the impacts of environmental evolutionary changes. Sediment chronology was determined using the Constant Rate of Supply model with the resultant ages verified by 137Cs horizons. Although the general contamination factors indicate low risk conditions in Bera Lake the risks associated with individual layers ranged from moderate to considerable. Five deforestation phases can be identified in the dated sediment cores with distinct variations in heavy metal influxes since 1972. These phases are in excellent agreement with the dates of land clearance and development projects undertaken over the past four decades. This study has highlighted the capability of contamination factors and chronological methods in environmental evolutionary studies where catchments have experienced extensive land use changes. The destiny of heavy metal influxes into a lake can also be revealed using this methodology. 相似文献
105.
Zakaria H. Aiube Sabah T. Najiam Abdul Amir H. Kadhum 《Research on Chemical Intermediates》2013,39(6):2351-2355
The compounds (E)-1,2-diphenyl-2-(phenylimino)ethanol, (E)-1,2-diphenyl-2-(p-tolylimino)ethanol, and (E)-2-((4-chlorophenyl)imino)-1,2-diphenylethanol) were synthesized by reaction of a p-substituted aniline with benzoin then oxidized with chromium trioxide–triethylamine in chloroform to give (E)-1,2-diphenyl-2-(phenylimino)ethanone, (E)-1,2-diphenyl-2-(p-tolylimino)ethanone, and (E)-2-((4-chlorophenyl)imino)-1,2-diphenylethanone in very high yield. The products were characterized by IR and NMR spectral analysis. 相似文献
106.
Wan Azlina Ahmad Nur Zulaikha Yusof Nordiana Nordin Zainul Akmar Zakaria Mohd Fazlin Rezali 《Applied biochemistry and biotechnology》2012,167(5):1220-1234
The present work highlighted the production of violacein by the locally isolated Chromobacterium violaceum (GenBank accession no. HM132057) in various agricultural waste materials (sugarcane bagasse, solid pineapple waste, molasses, brown sugar), as an alternative to the conventional rich medium. The highest yield for pigment production (0.82?g?L?1) was obtained using free cells when grown in 3?g of sugarcane bagasse supplemented with 10% (v/v) of l-tryptophan. A much lower yield (0.15?g?L?1) was obtained when the cells were grown either in rich medium (nutrient broth) or immobilized onto sugarcane bagasse. Violacein showed similar chemical properties as other natural pigments based on the UV?CVis, Fourier transform infrared spectroscopy, thin-layer chromatography, nuclear magnetic resonance, and mass spectrometry analysis. The pigment is highly soluble in acetone and methanol, insoluble in water or non-polar organic solvents, and showed good stability between pH?5?C9, 25?C100?°C, in the presence of light metal ions and oxidant such as H2O2. However, violacein would be slowly degraded upon exposure to light. This is the first report on the use of cheap and easily available agricultural wastes as growth medium for violacein-producing C. violaceum. 相似文献
107.
Y Abdollahi A Zakaria KA Matori K Shameli H Jahangirian M Rezayi T Abdollahi 《Chemistry Central journal》2012,6(1):100-5
ABSTRACT: BACKGROUND: The interactions of p-cresol photocatalytic degradation components were studied by response surface methodology. The study was designed by central composite design using the irradiation time, pH, the amount of photocatalyst and the p-cresol concentration as variables. The design was performed to obtain photodegradation % as actual responses. The actual responses were fitted with linear, two factor interactions, cubic and [left-to-right mark] quadratic model to select an appropriate model. The selected model was validated by analysis of variance which provided evidences such as high F-value (845.09), very low P-value (<.0.0001), non-significant lack of fit, the coefficient of R-squared (R2 = 0.999), adjusted R-squared (Radj2 = 0.998), predicted R-squared (Rpred2 = 0.994) and the adequate precision (95.94). RESULTS: From the validated model demonstrated that the component had interaction with irradiation time under 180 min of the time while the interaction with pH was above pH 9. Moreover, photocatalyst and p-cresol had interaction at minimal amount of photocatalyst (< 0.8 g/L) and 100 mg/L p-cresol. CONCLUSION: These variables are interdependent and should be simultaneously considered during the photodegradation process, which is one of the advantages of the response surface methodology over the traditional laboratory method. 相似文献
108.
109.
E. S. Zakaria I. M. Ali H. F. Aly 《Journal of Radioanalytical and Nuclear Chemistry》2004,260(2):389-397
Iron(III) (FeTi) and chromium (III) titanates (CrTi) were prepared as cation exchange materials in a granular form. The rate
of the isotopic exchange of Na+/*Na+ and Zn2+/*Zn2+ between aqueous solution and iron(III) and chromium(III) titanates in Na+ or Zn2+form has been carried out radiometrically in the 25-60 °C temperature range. The exchange rate is controlled by a particle
diffusion mechanism and experimental and theoretical approaches have been used to obtain the rate of diffusion through the
spherical particles of the exchangers. The values of self diffusion () of Na+ and Zn2+ ions were measured at different operation conditions, particle size, reaction temperatures and drying temperatures of the
matrix. The values of kinetic and thermodynamic parameters were calculated and their significance discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献