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81.
This paper reports a study on the effect of Al2O3 nanoparticles on the adhesion strength of steel-glass/epoxy composite joints bonded by a two-component structural acrylic adhesive. The addition of Al2O3 nanoparticles to the two-component acrylic adhesive led to a remarkable enhancement in the shear and tensile strength of the composite joints. The shear and tensile strength of the adhesive joints increased by addition of Al2O3 up to 1.5 wt%, which decreased by further addition of the nanofiller. Introduction of the nanoparticles caused a reduction in the peel strength of the joints. DSC analysis revealed that the glass transition temperature (Tg) of the adhesives rose by increasing the nanofiller content. The advancing water contact angle was decreased for adhesives containing nanoparticles. SEM micrographs indicated good dispersions of the Al2O3 nanoparticles within the acrylic matrix in the specimens with up to 1.5 wt% Al2O3 and revealed that addition of nanoparticles altered the fracture morphology from smooth to rough fracture surfaces. 相似文献
82.
MYMIV-AC2, a Geminiviral RNAi Suppressor Protein, Has Potential to Increase the Transgene Expression
Jamilur Rahman Sumona Karjee Sunil Kumar Mukherjee 《Applied biochemistry and biotechnology》2012,167(4):758-775
Gene silencing is one of the limiting factors for transgene expression in plants. But the plant viruses have learnt to suppress gene silencing by encoding the protein(s), called RNA silencing suppressor(s) (RSS). Hence, these proteins could be used to overcome the limitation for transgene expression. The RNAi suppressors, namely HC-Pro and P19, have been shown to enhance the transgene expression but other RSS proteins have not been screened for similar role. Moreover, none of RSSs from the DNA viruses are known for enhancing the expression of transgenes. The Mungbean Yellow Mosaic India Virus (MYMIV) belonging to the genus Begomovirus within the family of Geminiviridae encodes an RSS called the AC2 protein. Here, we used AC2 to elevate the expression of the transgenes. Upon introduction of MYMIV-AC2 in the silenced GFP transgenic tobacco lines, by either genetic hybridisation or transgenesis, the GFP expression was enhanced several fold in F1 and T0 lines. The GFP-siRNA levels were much reduced in F1 and T0 lines compared with those of the initial parental silenced lines. The enhanced GFP expression was also observed at the cellular level. This approach was also successful in enhancing the expression of another transgene, namely topoisomeraseII. 相似文献
83.
Emad A. Jaffar Al-Mulla Nor Azowa Bt Ibrahim Kamyar Shameli Mansor Bin Ahmad Wan Md. Zin Wan Yunus 《Research on Chemical Intermediates》2013,39(3):1313-1321
In this study, fatty amides (FAs) synthesized from palm olein were used to extract and separate Mo(VI) from acidic media. Effects of various parameters upon the separation of Mo(VI) from Co(II), Ni(II), Al(III) and Mn(II), including extractant concentration, metal ion concentration, contact time, diluent, and acidity, were investigated. It was found that Mo(VI) was successfully separated from the above commonly associated metal ions by stripping from the loaded organic phase. Different acidic and alkaline solutions were used. Ammonium hydroxide solution was an optimal. Extraction of Mo(VI) into the organic phase involved the formation of 1:3 complexes. This work presents the development of a low-cost and environmentally friendly extractant to recycle and recover molybdenum. 相似文献
84.
85.
Quinazoline is a heterocyclic compound having biological activities. It is aromatic in nature having bicyclic structure containing benzene ring and pyrimidine ring. Quinazoline and its derivatives are found to have wide range of biological activities that is anticancer, analgesic, antimicrobial, antihypertensive, anticonvulsant, antimalarial, antitumor, and anti-tubercular activities. The purpose of this review is to highlight the recent researches made by researchers on various biological activities of quinazoline derivatives on different targets. 相似文献
86.
Particle signals are detected by two parallel measuring chains which consist of a detector and analog to digital converter. We have used OPT101 as photodiode and ADS7870 for A/D converter and the output signal from two parallel measuring chains is processed by on line correlation filter. This filter works as real time systems. A correlation algorithm has been applied for this work. The signal to noise ratio has been increased by applying correlation filter. The gain of the filter has been improved by introducing digital signal processing. 相似文献
87.
In this paper, we exhibit the colorizing of brass surfaces by forming femtosecond laser induced microstructures on the sample surfaces. A variety of single colors such as brown, yellow, green, and black are introduced on brass surfaces by engineering periodic microgratings, microholes, and ring-shaped micro-patterns using Single Beam Direct Laser Writing (SBDLW) technique. The color of the micro-structured brass surfaces is certainly dependent on the width, depth, and period of the microstructures. Finally, we explain, in brief, the colorizing mechanism of metals by femtosecond laser induced microstructures. 相似文献
88.
Cold expansion is a useful process for imposing compressive residual stresses around the holes in riveted and bolted connections. These stresses increase the fatigue life of holed parts. Distribution and amount of exerted residual stress dependent on various parameters as material, distance of adjacent holes, hole diameter, cold expansion ratio and plate thickness. In this study, experimental and numerical results for two different aluminum alloys and various holes distances are investigated and compared. Effects of mentioned parameters on the residual stress are studied. 相似文献
89.
M. Y. A. Rahman A. Ahmad A. A. Umar R. Taslim M. S. Su’ait M. M. Salleh 《Ionics》2014,20(9):1201-1205
This paper reviews the use of solid polymeric electrolyte (SPE) and gel polymeric electrolyte (GPE) in photoelectrochemical cell (PEC) and dye-sensitized solar cell (DSSC). The structure of PEC and its working principle are presented. The various types of polymer electrolytes utilized in PEC and DSSC have been highlighted in this review. It also highlights the comparison of performance of PEC and DSSC utilizing those polymer electrolytes. This review is completed with the list of other SPEs that potentially be tested in DSSC. 相似文献
90.