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291.
This article presents a study of the erosion resistance of coated and uncoated polymer matrix composites for tidal turbine conditions. It focuses on the development of comparative erosive wear mode and mechanism maps for such materials. In our earlier work, testing of glass-fiber-reinforced polymer composites for tribological applications in marine simulated conditions, several erosion-related issues were highlighted. The combined effects of the NaCl solution and sand dramatically enhanced the erosive wear of the uncoated specimens. In order to address those issues, an erosion-resistant polymeric coating was applied to the composite and tested in marine simulated conditions with an extended range of sand particle size. The test results of the uncoated and coated composite have been compared in this research by erosive wear mode and mechanism maps techniques. These maps reveal that the coating has enhanced the erosion resistance. These findings provide significant progress toward materials selection approaches to manufacture of tidal turbine blades.  相似文献   
292.
The present study was carried out to investigate the polliniferous bee flora of Lakki Marwat district, Khyber Pakhtunkhwa, Pakistan. A total of 18 species, belonging to 13 different families were identified for the foraging activities of honeybees, namely, Cenchrus biflorus, Cestrum nocturnum, Citrus limon, Combretum indicum, Datura innoxia, Duranta erecta, Hamelia patens, Helianthus annuus, Ipomoea cairica, Luffa aegyptiaca, Nerium oleander, Ocimum basilicum, Parthenium hysterophorus, Pennisetum typhoides, Prosopis cineraria, Prosopis juliflora, Saccharum spontaneum, and Ziziphus jujuba. The identified melliferous flora was collected for the morpho‐palynological investigation. Pollen were acetolyzed, measured, and described qualitatively using light microscopy. The pollen types varied from psilate to echinate and colpi from tricolpate to hexacolpate. Quantitative characteristics including polar diameter, equatorial diameter, polar to equatorial ratio, colpi length, colpi width, spine length, spine width, and exine thickness of the pollen were determined and analyzed statistically using software IBM SPSS Statistics 20. The results of the present study highlighted the significance of pollen morphology of the bee flora of the area which may lead to the identification of the potential and useful botanical sources for beekeepers and to check the honey quality marketed from the study area.  相似文献   
293.
Wireless Personal Communications - Sudden accident in factories causes huge damage to human life and property which is a serious problem. The fire incident of Baldia Town factory Karachi, Pakistan...  相似文献   
294.
295.
Pattern Analysis and Applications - The most important intricacy when processing natural scene text images is the existence of fog, smoke or haze. These intrusion elements decrease the contrast and...  相似文献   
296.
Multimedia Tools and Applications - The use of social networks has grown exponentially in recent years. The large amount of data available in these networks can be effectively utilized in many...  相似文献   
297.
Ghulam Hussain  Gwilym J. Rees 《Fuel》1991,70(12):1399-1401
The effect of the addition of carbon and/or sulphur on potassium perchlorate (KClO4) decomposition has been studied by thermo-analytical techniques, i.e. thermogravimetric analysis (TGA), differential thermogravimetric analysis (DTGA), differential scanning calorimetry (d.s.c.) and Fourier transform infrared (FT-i.r.) spectroscopy. The TGA, DTGA and d.s.c. results show that carbon catalyses the decomposition of KClO4, and simultaneous decomposition of KClO4 and oxidation of carbon takes place in a solid phase. Addition of sulphur to KClO4 does not show any major effect but its presence in a ternary mixture (KClO4, carbon and sulphur) facilitates the decomposition/oxidation reaction. The FT-i.r. emission studies show that CO2 and SO2 are the major combustion products detectable by infrared spectroscopy.  相似文献   
298.
International Journal of Wireless Information Networks - This paper proposes an algorithm that enhances horizontal handover (HO) in dense wireless local area networks (WLANs), which is implemented...  相似文献   
299.
The poor kinetics of oxygen reduction reaction (ORR) invites a quest for the development of low-cost and efficient non-Pt electrocatalysts for fuel cells. Herein, a nanocomposite (g-[Co2N8]) was synthesized by coordination assembly of CoN4 macrocyclic moieties on graphene surface. The CoN4 macrocyclic complex was characterized by UV–Vis, FT-IR, Mass, 1H NMR and 13C NMR spectral studies, whereas UV–Vis, FT-IR, and Mass spectral, Raman, XRD and TEM studies were utilized to characterize the nanocomposite g-[Co2N8]. The results suggested that [CoN4] units are present in self-assembled [Co2N8] species. Further, the nanocomposite g-[Co2N8] was examined for ORR activity by employing cyclic and linear sweep voltammetry and found that the formal potential (E1/2) of g-[Co2N8] (+0.90 V) was more positive than 20% Pt/C (+0.86 V), indicating a remarkable ORR performance of g-[Co2N8] in comparison to 20% Pt/C, followed by 4e-mechanism. Moreover, the nanocomposite (g-[Co2N8]) displayed better ORR activity in comparison to [CoN4] complex which can be attributed to the synergistic incorporation of endo and exo N4–Co2+ moieties in the [Co2N8] species. In addition, g-[Co2N8] electrocatalyst exhibited a comparable stability to 20% Pt/C catalyst after 5000 cycles. This work will help to design multi-metallic coordination polymers with similar or different metal ions in N4-arrangement for various energy related electrocatalysis.  相似文献   
300.
In this study, we developed a novel, simple, rapid, and low-cost colloidal gold-based immunochromatography method, with filter paper replacing nitrocellulose membrane as the substrate. To obtain adequately immobilized protein, chitosan was used to functionalize the filter paper. After conditions and parameters were optimized, the novel immunochromatography method was applied for detection of sulfonamide residues in milk. Quantitative detection was accomplished using a smartphone and Photoshop software (Adobe Inc., San Jose, CA), allowing us to screen 13 sulfonamides with a limit of detection ranging from 0.42 to 8.64 μg/L and recovery ranging from 88.2 to 116.9% in milk. The proposed novel method performed similarly to the conventional method that uses a nitrocellulose membrane as the transport medium, and it had lower cost and better usability because of the inexpensive and easily available filter paper.  相似文献   
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