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21.
In this study, wool fibers are modified by low frequency plasma polymerization of acrylic acid regarding to its' hydrophobic character due to cuticular cells at their surfaces. Variables of the plasma glow discharge processes were power (40–100 W) and exposure time (5–45 min). The effect of plasma modification in the performance properties of wool were investigated on the basis of hydrophilicity of wool, average wrinkle recovery angle, and breaking strength. The surface chemical structures of fabrics were examined with x‐ray photoelectron spectroscopy. The hydrophobic wool fabric became hydrophilic after all plasma treatments except one (40W–5 min). Average wrinkle recovery angle of the treated fabrics were between 157 and 178°, while that of untreated fabric was 180°. The treated fabrics had a little bit lower angles according to the untreated fabric. However, even the lowest value as 157° means that the fabric has a good crease resistance property. The breaking strengths of fabrics were increased up to 26% after the plasma treatments. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   
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Addressed herein, a highly effective and monodisperse Pt/L@rGO nanocatalysts were successfully synthesized by using different types of ligands (pentylamine, Pt/PA@rGO and tripentylamine, Pt/TPA@rGO) and the impact of ligand on catalytic activity of the prepared nanomaterials have been examined for methanol oxidation. An easy and facile ultrasonication method was applied to produce highly efficient, monodispersed and durable (Pt) NPs dispersed on reduced graphene oxides (rGO). The structure morphology, composition and properties of Pt/L@rGO NPs were characterized by using different techniques such as ICP-OES, XPS, TEM, HRTEM, and XRD methods. A different ligand based monodisperse Pt (0) nanocatalysts have been compared with each other and commercial catalysts in terms of catalytic performance, life-time and reusability of catalyst for methanol oxidation reaction in THF at room temperature. All experimental results demonstrate the highly stable and reusable rGO furnished Pt (0) nanomaterials and their excellent catalytic performance in the methanol oxidation reactions at room temperature.  相似文献   
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Ambient air and dry deposition samples were collected at suburban and urban sites in Izmir, Turkey. Atmospheric total (particle+gas) ∑(14)PAHs concentrations were 36±39 and 144±163 ng m(-3) for suburban and urban sites, respectively. Phenanthrene was the most abundant compound at all sites, and all samples were dominated by low molecular weight PAHs. Average particulate ∑(14)PAH dry deposition fluxes were 8160±5024 and 4286±2782 ng m(-2) day(-1) and overall average particulate dry deposition velocities were 1.5±2.4 and 1.0±2.3 cm s(-1) for suburban and urban sites, respectively. Soil samples were collected at suburban site. Average soil concentration for ∑(14)PAH was 55.9±14.4 ng g(-1) dry weight. Calculated gas-phase air-soil exchange fluxes indicated that fluorene, phenanthrene, anthracene, and carbazole were deposited to soil in winter while they were volatilized in summer. Other compounds (fluoranthene-benzo[g,h,i]perylene) were deposited to soil in both periods. Annual average fluxes of PAHs representing soil to air (i.e., gas volatilization) and air to soil transfer (i.e., gas absorption, dry deposition, and wet deposition) processes were also compared. All processes were comparable for Σ(14)PAHs however their input was dominated by gas absorption. Gas absorption dominated for lower molecular weight PAHs, however dry deposition dominated for higher molecular weight PAHs. The results have suggested that for fluorene, soil and air may be approaching a steady state condition. For the remaining compounds, there was a net accumulation into the soil.  相似文献   
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In this study, the structural, electrical, and electromagnetic properties of cotton fabrics coated with polyaniline (PAni) and polypyrrole (PPy) were investigated and compared. For the aims, anilin and pyrrole were used as monomers, and in situ polymerization on cotton fabric by chemical oxidative polymerization was performed. After production, the structural properties of the fabrics were determined with Fourier transform infrared spectroscopy and X‐ray diffraction. In addition, ultraviolet (UV) permeability, tensile strength, colorfastness, and electrical and electromagnetic measurements of the fabric samples were carried out. The resistance values of the cotton fabrics coated with PAni and PPy were found to be 350 and 512 Ω, respectively. The average electromagnetic shielding efficiency and average absorption values of the cotton fabrics coated with PAni were determined to be 3.8 dB and 48%, respectively, and these values for the cotton fabrics coated with PPy were 6 dB and 50%, respectively. Consequently, a significant difference was not observed between the resistance values and electromagnetic parameters of the fabrics coated with PAni and PPy, although the intact textile characteristics of the fabric coated with PPy were protected and improved, whereas the characteristics of the fabric coated with PAni were inferior. Moreover, we first report that the fabrics coated with conductive polymers had excellent UV‐protection properties. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
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Conducting polymer composites of polythiophene, using a polyamide as the insulating matrix, were prepared via electrochemical methods. The characterization of the composite was done by scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, Fourier transform infrared and pyrolysis studies. The conductivities were measured by a four-probe technique. The cited methods revealed that the composites have properties different from those of simple mechanical mixtures of the two polymers.  相似文献   
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Objectives

To evaluate the corneal confocal microscopy and dry eye findings in patients with contact lens discomfort.

Methods

The study included 3 groups of participants: Contact lens wearers using silicone hydrogel soft contact lenses who are symptomatic (CLD, n = 15) or asymptomatic (ACL, n = 11) and non-wearers as controls (n = 14). Duration of contact lens wear, Ocular Surface Disease Index (OSDI) questionnaire responses, fluorescein tear break-uptime (FBUT), and corneal confocal microscopy findings were recorded.

Results

Mean age was 25.7 ± 8.2 years and male/female ratio was 7/33. Demographic findings were similar regarding the groups. CLD patients had a longer lens use history than ACL (median 5 vs 2 years, p < 0.001). OSDI scores were higher in CLD group than ACL or controls (p < 0.001, p = 0.002). FBUT was significantly lowest in CLD group, compared to controls and ACL (p < 0.001, p = 0.039). FBUT was also lower in ACL patients compared to controls (p = 0.036). There was no difference between basal epithelium cell counts between all 3 groups. Anterior stromal activated keratocyte numbers were similar between contact lens using groups but was lower in controls (p = 0.005). However, dendritiform cells in the sub-basal nerve layer were higher in CLD group compared to controls but similar to ACL (p < 0.001, p = 0.058). Graded sub-basal nerve tortuosity was more prominent in CLD group than the ACL (p = 0.014).

Conclusion

Patients with CLD had been wearing contact lenses for longer than those without symptoms. OSDI and FBUT scores were worse in CLD patients. In contact lens discomfort patients, there were increased dendritiform cells, indicating intensified inflammatory status of the cornea.  相似文献   
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