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91.
Fisal Ahmad Wan Mohd Ashri Wan Daud Mohd Azmier Ahmad Rosinah Radzi 《Chemical Engineering Research and Design》2012
Cocoa shell (CS) was used as a low-cost precursor for production of activated carbon (AC) and evaluated for its ability to adsorb Methylene Blue (MB) dye. Cocoa shell-based pellets were carbonized at 800 °C and subjected to 850 °C under a flow of CO2 in different activation times. The cocoa (Theobroma cacao) shell-based activated carbon (CSAC) showed moderate surface area with the average pore size 2.7 nm. CSAC also displays the presence of aliphatic, aromatic hydrocarbons and near absence of C–O, carboxylic acid, and the –COOH functional group. Only the presence of O–H groups was detected. The influences of adsorption time and initial dye concentration on adsorption performance have been measured in a batch system. The results are well described by the Freundlich and Langmuir isotherms. The results from the kinetic study show that MB adsorption follows pseudo-second-order and Boyd models, which indicated the MB adsorption on the CSAC was controlled by film diffusion. 相似文献
92.
Wan Azelee Wan Abu Bakar Mohd Yusuf Othman Rusmidah Ali Ching Kuan Yong 《Catalysis Letters》2009,128(1-2):127-136
Supported nickel oxide based catalysts were prepared by wetness impregnation method for the in-situ reactions of H2S desulfurization and CO2 methanation from ambient temperature up to 300 °C. Fe/Co/Ni (10:30:60)–Al2O3 and Pr/Co/Ni (5:35:60)–Al2O3 catalysts were revealed as the most potential catalysts, which yielded 2.9% and 6.1% of CH4 at reaction temperature of 300 °C, respectively. From XPS, Ni2O3 and Fe3O4 were suggested as the surface active components on the Fe/Co/Ni (10:30:60)–Al2O3 catalyst, while Ni2O3 and Co3O4 on the Pr/Co/Ni (5:35:60)–Al2O3 catalyst. 相似文献
93.
Eman M. E. Dokla Chun‐Sheng Fang Po‐Ting Lai Dr. Samuel K. Kulp Dr. Rabah A. T. Serya Dr. Nasser S. M. Ismail Prof. Khaled A. M. Abouzid Prof. Ching‐Shih Chen 《ChemMedChem》2015,10(11):1915-1923
Previously, we reported the identification of a thiazolidinedione‐based adenosine monophosphate activated protein kinase (AMPK) activator, compound 1 (N‐[4‐({3‐[(1‐methylcyclohexyl)methyl]‐2,4‐dioxothiazolidin‐5‐ylidene}methyl)phenyl]‐4‐nitro‐3‐(trifluoromethyl)benzenesulfonamide), which provided a proof of concept to delineate the intricate role of AMPK in regulating oncogenic signaling pathways associated with cell proliferation and epithelial–mesenchymal transition (EMT) in cancer cells. In this study, we used 1 as a scaffold to conduct lead optimization, which generated a series of derivatives. Analysis of the antiproliferative and AMPK‐activating activities of individual derivatives revealed a distinct structure–activity relationship and identified 59 (N‐(3‐nitrophenyl)‐N′‐{4‐[(3‐{[3,5‐bis(trifluoromethyl)phenyl]methyl}‐2,4‐dioxothiazolidin‐5‐ylidene)methyl]phenyl}urea) as the optimal agent. Relative to 1 , compound 59 exhibits multifold higher potency in upregulating AMPK phosphorylation in various cell lines irrespective of their liver kinase B1 (LKB1) functional status, accompanied by parallel changes in the phosphorylation/expression levels of p70S6K, Akt, Foxo3a, and EMT‐associated markers. Consistent with its predicted activity against tumors with activated Akt status, orally administered 59 was efficacious in suppressing the growth of phosphatase and tensin homologue (PTEN)‐null PC‐3 xenograft tumors in nude mice. Together, these findings suggest that 59 has clinical value in therapeutic strategies for PTEN‐negative cancer and warrants continued investigation in this regard. 相似文献
94.
SPEEK/cSMM membrane for simultaneous electricity generation and wastewater treatment in microbial fuel cell 下载免费PDF全文
95.
Seyyed Reza Pishva Ramachandran Vasudevan Ali Etemad Farzad Heidari Makanko Komara Patimah Ismail Fauziah Othman Abdollah Karimi Mohammad Reza Sabri 《International journal of molecular sciences》2013,14(2):2739-2752
Ventricular septal defect (VSD) is one of the most common types of congenital heart defects (CHD). There are vivid multifactorial causes for VSD in which both genetic and environmental risk factors are consequential in the development of CHD. Methionine synthase reductase (MTRR) and methylenetetrahydrofolate reductase (MTHFR) are two of the key regulatory enzymes involved in the metabolic pathway of homocysteine. Genes involved in homocysteine/folate metabolism may play an important role in CHDs. In this study; we determined the association of A66G and C524T polymorphisms of the MTRR gene and C677T polymorphism of the MTHFR gene in Iranian VSD subjects. A total of 123 children with VSDs and 125 healthy children were included in this study. Genomic DNA was extracted from the buccal cells of all the subjects. The restriction fragment length polymorphism polymerase chain reaction (PCR-RFLP) method was carried out to amplify the A66G and C524T polymorphism of MTRR and C677T polymorphism of MTHFR genes digested with Hinf1, Xho1 and Nde1 enzymes, respectively. The genotype frequencies of CC, CT and TT of MTRR gene among the studied cases were 43.1%, 40.7% and 16.3%, respectively, compared to 52.8%, 43.2% and 4.0%, respectively among the controls. For the MTRR A66G gene polymorphism, the genotypes frequencies of AA, AG and GG among the cases were 33.3%, 43.9% and 22.8%, respectively, while the frequencies were 49.6%, 42.4% and 8.0%, respectively, among control subjects. The frequencies for CC and CT genotypes of the MTHFR gene were 51.2% and 48.8%, respectively, in VSD patients compared to 56.8% and 43.2% respectively, in control subjects. Apart from MTHFR C677T polymorphism, significant differences were noticed (p < 0.05) in C524T and A66G polymorphisms of the MTRR gene between cases and control subjects. 相似文献
96.
Polyester‐ and epoxy‐based composites containing glass and carbon fibers were manufactured using a vacuum‐assisted resin transfer molding (VARTM) process. Fourier transform infrared (FTIR) spectroscopy analyses were conducted to determine the interaction between fibers and matrix material. The results indicate that strong interaction was observed between carbon fiber and epoxy resin. However, weak interactions between remaining fiber‐matrix occur. Scanning electron microscopy (SEM) analysis was also performed to take some information about strength of interaction between fibers and matrix material. From SEM micrographs, it is concluded that the findings in SEM analysis support to that obtained in FTIR analysis. Another aim of the present work was to investigate the influence of matrix on composite properties. Hence, the strengths of composites having same reinforcement but different matrix systems in axial tension and transverse tension were compared. Short beam shear test has been conducted to characterize the interfacial strength in the composites. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
97.
Mohd Azlan Hussain Mohamed Kheireddine Aroua Chun-Yang Yin Ramzalina Abd Rahman Noor Asriah Ramli 《Korean Journal of Chemical Engineering》2010,27(6):1864-1867
The solubility of CO2 in single monoethanolamine (MEA) and diethanolamine (DEA) solutions was predicted by a model developed based on the Kent-Eisenberg
model in combination with a neural network. The combination forms a hybrid neural network (HNN) model. Activation functions
used in this work were purelin, logsig and tansig. After training, testing and validation utilizing different numbers of hidden nodes, it was found that a neural network with
a 3-15-1 configuration provided the best model to predict the deviation value of the loading input. The accuracy of data predicted
by the HNN model was determined over a wide range of temperatures (0 to 120 °C), equilibrium CO2 partial pressures (0.01 to 6,895 kPa) and solution concentrations (0.5 to 5.0M). The HNN model could be used to accurately
predict CO2 solubility in alkanolamine solutions since the predicted CO2 loading values from the model were in good agreement with experimental data. 相似文献
98.
Ismail Aiad Mohamed M. EL-Sukkary Ali El-Deeb Moshira Y. El-Awady Samy M. Shaban 《Journal of surfactants and detergents》2013,16(2):243-250
A series of novel iminium surfactants were prepared through quaternization of different prepared fatty Schiff bases with benzyl chloride. The chemical structures were confirmed using FTIR, 1H-NMR and mass spectroscopy. The surface properties and biological activity of these surfactants were investigated. The surface parameters including critical micelle concentration (CMC), maximum surface excess (Γmax) and minimum surface area (A min), Efficiency (PC20) and Effectiveness (πCMC) as well as the free energy of micellization ( $ \Updelta G_{\text{mic}}^{\text{o}} $ ) and adsorption ( $ \Updelta G_{\text{ads}}^{\text{o}} $ ) were calculated. It was found that the prepared compounds have good surface and biological activity. 相似文献
99.
Ethylene propylene diene monomer rubber (EPDM)-based composites containing sepiolite (sep) hybridized with calcium carbonate (CaCO3), silica (Sil) or carbon black (CB) were prepared on a two-roll mill. The influence of fillers’ contents on the curing, mechanical, thermal and flammability of the composites was investigated. In comparison with EPDM/sep at 30 parts per hundred rubbers (phr) as a control composite, EPDM/sep/CB composites exhibited an outstanding improvement in tensile strength followed by EPDM/sep/Sil and EPDM/sep/CaCO3 composites. EPDM/sep/CB displayed the highest thermal stability and also improved flammability resistance. In addition, a higher amount of carbon black gave higher tensile strength. The results were influenced by the ability of CB to disperse well and form protective layers acting as mass transport barriers in the matrix. The field emission scanning electron microscopy analyses proved better dispersion of CB in the matrix. The presence of protective layers on the surface of samples consequently improved the thermal properties of the EPDM composites. The mechanism of formation of char protective layer in hybrid EPDM composites was also investigated based on morphological observations of char residues. According to this work, Sil and CB were able to hybrid with sep, while sep could be a potential substitution of CaCO3 in the EPDM composites. 相似文献
100.
Compressive mechanical properties of sawdust/high density polyethylene composites under various strain rate loadings 下载免费PDF全文
Haliza Jaya Mohd Firdaus Omar Hazizan Md Akil Zainal Arifin Ahmad Nik Noriman Zulkepli Mohd Mustafa Al Bakri Abdullah 《乙烯基与添加剂工艺杂志》2018,24(2):162-173
This article is concerned with the static and dynamic mechanical properties of high‐density polyethylene (HDPE) reinforced with sawdust (SD) at a strain rate of up to 103 s?1. In this study, the static and dynamic properties of HDPE/SD composites with different filler loadings of 5, 10, 15, 20, and 30 wt% SD were deliberated at different levels of strain rates (0.001, 0.01, 0.1, 650, 900, and 1100 s?1) using a conventional universal testing machine and the split Hopkinson pressure bar apparatus. The results showed that the stress–strain curves, yield behavior, stiffness, and strength properties of the HDPE/SD composites were strongly affected by both the strain rate and the filler loadings. Furthermore, the rate sensitivityof the HDPE/SD composites showed a great dependency on the applied strain rate, increasing as the strain rate increased. However, the thermal activation values showed a contrary trend. Meanwhile, for the postdamage analysis, the results showed that the applied strain rates influenced the deformation behavior of the tested HDPE/SD composites. Moreover, for the fractographic analysis at dynamic loading, the composites showed that all the specimens underwent a severe catastrophic deformation. J. VINYL ADDIT. TECHNOL., 24:162–173, 2018. © 2016 Society of Plastics Engineers 相似文献