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Chemical vapor deposition of poly(3‐alkylthiophene) nanoparticles on fabric: Chemical and electrochemical characterization 下载免费PDF全文
Chemical vapor deposition of poly(3‐methylthiophene) and poly (3‐hexylthiophene) as conductive polymers on the surface of polyester fabrics was successfully obtained. Fourier transform infrared spectroscopy confirmed the formation of polymers on surface of fabrics (the fingerprint of polythiophenes, υ 600–1500 cm?1). The uniformity of deposition and nanoparticles (average size of 60 nm) were proved with scanning electron microscopy. Electrochemical impedance spectroscopy showed that P3HT‐coated samples offer higher conductivity in compared to P3MT‐coated samples. The impedance modulus of P3HT‐coated samples was lowered nine times to that of row materials and reached to c8000 Ω. The samples have also shown electrochromic properties under electrical current, changing its color from yellowish green at 0 V to dark green at +12 V for poly (3‐hexylthiophene) samples and from brown at 0 V to red at +12 V for poly(3‐methylthiophene)‐coated fabrics (V = 0 V, λ = 450 nm; V = 12 V, λ = 650 nm). © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40673. 相似文献
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Heat assisted magnetic recording (HAMR) is proposed for the next generation of hard disk drives. In HAMR systems, a laser beam heats the disk magnetic layer to the Curie temperature. This may cause the thin film lubricant coating the disk to deplete due to evaporation and surface tension gradient. In this study, we perform simulations for the Z-tetraol family of lubricants with four hydroxyl end-groups, including Z-tetraol 1200 as a low molecular weight member of the family and Z-tetraol 2200 as a high molecular weight of the family, and also for ZTMD (2,200 Da) with eight hydroxyl groups as a multi-dentate lubricant, which is manufactured based on the Z-tetraol family. All studies are performed for four cases of lubricant thicknesses including 5, 7, 12, and 14A. These numbers are chosen in order to provide a fair comparison with a previous study for Z-dol. We also investigate the relative effects of evaporation with respect to the thermocapillary shear stress. It is found that after a 2 ns illumination of the laser, a trough and two side ridges across the down-track direction can be seen in the lubricant. The performances of the lubricants can be ranked mainly based on the trough depth and also evaporation such that better lubricants show less deformation and trough depth under equal conditions of thermal spot size and peak temperature. We also found that all of the lubricants deplete rapidly and their depletion speed decreases gradually. 相似文献
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Shabnam Ashhari Ali Asghar Sarabi Seyed Mahmoud Kasiriha Davood Zaarei 《应用聚合物科学杂志》2011,119(1):523-529
Polyurethane (PU)–clay nanocomposite coatings were prepared by a sonication method. The stability and morphology of these coatings was characterized by turbidometry, X‐ray diffraction, and transmission electron microscopy. The anticorrosive properties of these coatings were investigated by salt‐spray and electrochemical impedance spectroscopy methods. According to the results, dispersed nanoclay layers in the matrix of the nanocomposite coating compositions led to superior anticorrosive characteristics compared to those of pure PU coatings. The best results were obtained with coatings containing about 5 wt % clay. The resistance of the coating containing 5% clay was about 9.002 GΩ after 225 days of immersion in a 3.5 wt % NaCl solution, whereas it was only 97 kΩ for the pure PU coating. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
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The corrosion inhibition effect of cationic surfactants, DTAB (Dodecyl Trimethyl Ammonium Bromide) and TTAB (Tetradecyl Trimethyl Ammonium Bromide), on low carbon steel was studied using weight loss, open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) measurements. The effect of chain length compatibility on corrosion inhabitancy of surfactant and co-surfactant was investigated by C7OH (1-heptanol), C12OH (1-dodecanol) and C15OH (1-pentadecanol) as nonionic co-surfactants in acidic media at different concentrations of DTAB and TTAB. Data represented that the corrosion rate decreased by increasing concentration of DTAB and TTAB, independently. The effect of chain length compatibility on surfactant behavior was discussed. Decreasing of corrosion rate for DTAB + C12OH was more pronounced than other mixtures. 相似文献
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H. Eivaz Mohammadloo A.A. Sarabi R. Mohammad Hosseini M. Sarayloo H. Sameie R. Salimi 《Progress in Organic Coatings》2014
The effect of four practical parameters (deposition temperature, time, bath pH and concentration of Zr) on electrochemical and morphological properties of zirconium based conversion coating (ZrCC) on cold rolled steel (CRS) substrates was investigated. DC polarization and electrochemical impedance spectroscopy (EIS) measurements were used for electrochemical studies. Micro structural characterization was carried out by FE-SEM, AFM and EDS. The optimal conditions were determined as follows: solution temperature 20–30 °C, immersion time 60–120 s, pH = 4 and acid concentration of 4% vol. In such condition, corrosion resistance values were maximum and uniformity was improved. Microscopical observations revealed that ZrCC comprises a two-layered structure. The film formation mechanism of ZrCC was discussed in detail. After achieving the optimum conditions, epoxy nanocomposites were applied on ZrCC treated CRS samples and corrosion performance of fully painted system was investigated. Finally the adhesion strength of subsequently applied organic coating on ZrCC treated substrates was measured by pull-off technique which exhibited considerable high values. 相似文献
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R. Salimi H. Sameie A. A. Sabbagh Alvani A. A. Sarabi F. Moztarzadeh H. Eivaz Mohammadloo F. Nargesian M. Tahriri 《Journal of Materials Science》2012,47(6):2658-2664
In this research, a new blue-emitting phosphor Eu2+-doped SrZn2Si2O7 was developed for white light-emitting diodes via the sol–gel process. Thermogravimetric-differential thermal analysis, X-ray
diffraction, scanning and transmission electron microscopy (SEM and TEM), and photoluminescence (PL) spectra were used to
characterize the resulting phosphors. The obtained phosphor is efficiently excited in the wavelength range of 340–400 nm which
matches to a near-UV-emitting InGaN chip and emits strong band blue light peaking at 481 nm because of 4f
65d
1(2
D) → 4f
7(8
S
7/2) transition of Eu2+ ions. The effects of the activator concentration and excess Si (y > 1) on the luminescence properties were evaluated. It
was found that, when the Eu2+ content (x) and the Si concentration (2y) were 0.04 and 2.4, respectively, the optimum phosphor can be achieved. Also, the mechanism of concentration quenching was
determined to be the dipole–dipole interaction using Dexter’s theory. Finally, the mean crystallite size of the products was
estimated to be approximately 30 nm using Scherrer’s equation, which was confirmed by the TEM observations. 相似文献
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Cardiac and vascular structure and function are related to lipid peroxidation and metabolism 总被引:2,自引:0,他引:2
The present study investigated possible relationships between left ventricular mass, intima-media thickness of the carotid
artery (IMT), total arterial compliance, and lipid status in a population sample of 58 apparently healthy subjects aged 20
to 69. By stepwise multiple regression analysis, including age, blood pressure, and smoking, left ventricular mass index,
measured by M-mode echocardiography, increased by 13.0 g/m2 for each 1 standard deviation (SD=0.11 μM, r=0.60, P<0.01) increase in plasma malondialdehyde and 9.50 g/m2 per SD increase in plasma 8-iso-prostaglandin F2α in women only (SD=8.88 ng/L, r=0.44, P=0.01). Each 1-SD (SD=0.27 g/L) increase in apolipoprotein B was associated with a 63 μm increase in IMT (r=0.47, P=0.01) and a 0.27 mL/min/m2/mm Hg (r=−0.60, P<0.01) decrease in stroke index/pulse pressure ratio, reflecting total arterial compliance in women. In men, each 1-SD increase
in the proportion of stearic acid (18∶0) in serum cholesterol esters (SD=0.12 percent units) reduced the transmitral E/A ratio,
measured by Doppler echocardiography, reflecting left ventricular diastolic function, by 0.10 units (r=−0.29, P<0.05). Thus, important cardiovascular characteristics, such as left ventricular mass, left ventricular diastolic function,
carotid IMT, and total arterial compliance, were independently predicted by indices of lipid metabolism and peroxidation in
apparently healthy subjects. 相似文献
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Davood Zaarei Ali Asghar Sarabi Farhad Sharif Mohsen Moazzami Gudarzi Seyed Mahmoud Kassiriha 《Journal of Coatings Technology and Research》2012,9(1):47-57
The present work reports on a new approach to the preparation of special corrosion-resistant epoxy coatings. The aminic hardener
of these coatings contained emeraldine-base polyaniline (EB-PANi). The aminic hardener was prepared by dispersion of EB-PANi
in 3-(aminomethyl)-3,5,5-trimethylcyclohexan-1-amine employing sonication, centrifuging and submicron filtering methods. The
state of dispersion and dissolution of these coating materials, during different stages of preparation, were characterized
by optical microscopy and scanning electron microscopy. The corrosion resistances of resulting coatings were measured by electrochemical
impedance spectroscopy (EIS) and salt spray methods. As little as 0.5% EB in initial mixture of EB-hardener compositions led
to relatively better corrosion protection of resulting coating compared with neat resin coating. Presence of initial 2.5%
of EB in the hardener and its processing through our approach resulted in the formulation of an epoxy coating with superior
corrosion protection properties. 相似文献