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991.
Ivan Isakov Hendrik Faber Max Grell Gwenhivir Wyatt‐Moon Nikos Pliatsikas Thomas Kehagias George P. Dimitrakopulos Panos P. Patsalas Ruipeng Li Thomas D. Anthopoulos 《Advanced functional materials》2017,27(22)
The growth mechanism of indium oxide (In2O3) layers processed via spray pyrolysis of an aqueous precursor solution in the temperature range of 100–300 °C and the impact on their electron transporting properties are studied. Analysis of the droplet impingement sites on the substrate's surface as a function of its temperature reveals that Leidenfrost effect dominated boiling plays a crucial role in the growth of smooth, continuous, and highly crystalline In2O3 layers via a vapor phase‐like process. By careful optimization of the precursor formulation, deposition conditions, and choice of substrate, this effect is exploited and ultrathin and exceptionally smooth layers of In2O3 are grown over large area substrates at temperatures as low as 252 °C. Thin‐film transistors (TFTs) fabricated using these optimized In2O3 layers exhibit superior electron transport characteristics with the electron mobility reaching up to 40 cm2 V?1 s?1, a value amongst the highest reported to date for solution‐processed In2O3 TFTs. The present work contributes enormously to the basic understanding of spray pyrolysis and highlights its tremendous potential for large‐volume manufacturing of high‐performance metal oxide thin‐film transistor electronics. 相似文献
992.
Faze Chen Yao Lu Xin Liu Jinlong Song Guanjie He Manish K. Tiwari Claire J. Carmalt Ivan P. Parkin 《Advanced functional materials》2017,27(41)
Many advanced materials are designed for separation of immiscible oils/organic solvents and aqueous solutions, including poly(vinylidene fluoride) (PVDF)‐based materials with superwettability. However, due to the limited solubility of PVDF, techniques (e.g., phase inversion and electrospinning) often involve the use of toxic organic solvents. Here a facile organic solvent‐free method is described to prepare a porous PVDF–MWCNT (multiwalled carbon nanotube) foam using table salt as a sacrificial template. The porous PVDF–MWCNT foam is characterized as superhydrophobic–superoleophilic with good elasticity due to its 3D porosity and low surface energy. The foam exhibits high adsorption capacity to a variety of oils/organic solvents and can be easily reused by squeezing, heating, or releasing in other solvents. Moreover, the foam is highly resistant toward UV exposure, corrosive aqueous solutions such as acidic, alkaline, salty solutions, and turbulent environments, and shows effective oils/organic solvents removal in these complex environments. The continuous separation of immiscible oils/organic solvents and corrosive aqueous solutions with vacuum assistance is also presented. The organic solvent‐free and reusable PVDF–MWCNT foam is a promising candidate for large‐scale industrial separation of oils/organic solvents and water in corrosive and turbulent conditions. 相似文献
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The paper is focused on calculation of the average droplet size in immiscible blends during their steady flow. Available theoretical and experimental results of studies of the droplet breakup and coalescence are utilized to derive the equations describing dynamic equilibrium between the droplet breakup and coalescence. New expression for the coalescence efficiency, reliably reflecting recent theoretical results, is proposed. The equation for the average steady droplet size, controlled by the stepwise breakup mechanism and coalescence of droplets with not very different sizes, is derived for blends containing up to 10–20 vol % of the droplets. For blends with above approximate 20 vol % of the droplets, the breakup by the Tomotika mechanism and coalescence in highly polydisperse system is modeled. Results of the derived equations are compared with experimental data; qualitative agreement is found for the dependence of the droplet size on the amount of the dispersed phase. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45250. 相似文献
997.
Sumita Swar Veronika Zajícová Miroslava Rysová Irena Lovětinská‐Šlamborová Lukáš Voleský Ivan Stibor 《应用聚合物科学杂志》2017,134(26)
Poly(ethylene terephthalate)—PET, is one of the most common polyesters, widely used in biomedical applications ranging from catheters to stents, vascular grafts, heart valves, sutures, and scaffolds. PET surface modification is necessary to impart desired properties for biomedical applications, making the polymer biocompatible, noncytotoxic and antibacterial that can preferably resist biofilm formation caused by pathogenic bacteria. A novel approach to anticorrosive wet chemical surface modification of PET by insertion of alkyl and hydroxyl groups was achieved by using Grignard reagents and confirmed by several different characterization methods including Fourier transform infrared spectroscopy (FTIR), water contact angle (WCA) measurement, free surface energy (FSE) measurement, scanning electron microscopy (SEM), and atomic force microscopy (AFM). High antibacterial efficiency against four different types of biofilm active, pathogenic bacterial strains namely: Staphylococcus aureus, Escherichia coli, methicillin‐resistant S. aureus (MRSA), and Pseudomonas aeruginosa was established on the modified PET surface. Biocompatibility higher than 84% of the modified samples has been proved. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44990. 相似文献
998.
Stelian Stan Mihai Chisamera Iulian Riposan Nicoleta Ivan Michael Barstow 《Journal of Materials Engineering and Performance》2012,21(8):1793-1799
A program was conducted to research how to characterize the size and shape of micro-particles. These can act as graphite nuclei, but are altered by adding a commercial iron powder, or after a similar treatment combined with inoculation. Resin sand mold (RSM) and metal mold (MM) solidified sample structures were subjected to automatic image analysis. In general, a higher cooling rate, typical for MM solidification, favors smaller size and more compact particles, even in RSM media. Iron powder treatment led to the largest particles with unusual morphologies, better defined by complex shape factors, which employ actual perimeters, rather than the simpler median size and aspect ratio method. Conventional inoculation employed after an iron powder treatment altered the particles (smaller and more compact), which benefited their effectiveness to act as graphite nuclei, especially at slower solidification rates in RSMs. The results confirm that promoting more compact micro-inclusions, at smaller sizes, involved in graphite nucleation, reduces the sensitivity to chill and improves the eutectic cell characteristics in gray cast iron. 相似文献
999.
The recent improvements in the design and production of gears are not matched by the improvements in the development of measuring
techniques and evaluation standards which can, in short time, give precise information about the quality of the produced gear.
The inspection of gears with tooth flank modifications is still conducted by measuring of the profile and flank lines, pitch
and concentricity. Furthermore topographical measurement on the coordinate measuring machine is an expensive and lasting process.
This paper presents the development of a new, flexible gear-measuring machine called RollScan, which can measure the entire
gear topography in a few minutes and can be introduced directly into the production line. For this, a machine with four axes
and the control, a new one tooth roll master and evaluation software is designed, which makes the machine flexible and enables
a variety of gear measurements without any special mechanical adjustments.
The investigations described in this paper were sponsored by InnoNet from BMWi (16IN0276). 相似文献
1000.
In the present work, the corrosion protection of aluminum alloy AA2024-T3 has been studied in NaCl solution, with and without the addition of cerium (III) chloride heptahydrate. The corrosion inhibitor efficiency after immersion into 10 mM NaCl, with or without 3 mM of CeCl3·7H2O at 20°C, 40°C, and 60°C was investigated. The performed quantitative tests include electrochemical techniques, such as the method of quasipotentiostatic polarization (Tafel extrapolation), cyclic polarization, and electrochemical impedance s pectroscopy to determine corrosion rate (vcorr), inhibition efficiency (η %), protective ability (γ), degree of coverage (ϑ), and pitting nucleation resistance. The samples were analyzed with scanning electron microscopy and energy dispersive X-ray analysis to evaluate and characterize the precipitates formed on the surface of aluminum samples and to determine dominant type of corrosion. The formation of Ce3+ precipitates occurred on cathodic intermetallic sites and the surface, in general, resulting in improved corrosion resistance. Tested cerium (III) chloride heptahydrate proved to be an effective inorganic corrosion inhibitor for AA2024-T3 in chloride solution, which, by the action of cerium ions, reduced corrosion on the surface of the studied aluminum alloy. 相似文献