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111.
Utilization of Electrospun Polystyrene Membranes as a Preliminary Step for Rapid Diagnosis 下载免费PDF全文
Recent advances in clinical practice drive deoxyribonucleic acid (DNA) as an important class of biomarker. Monitoring the change in their concentration suggests the initiation and/or progression of various disorders. However, low quantity of DNA biomarkers in body fluids requires a delicate isolation methodology that provides efficient separation and easy handling. This study describes a newer‐generation separation technology relying on electrospun fibers of sub‐micrometer diameter of a commodity polymer for DNA biomarkers in simulative serum. Fibrous polystyrene membranes are prepared by electrospinning and they are subjected to post‐modification with Au. The composite membranes may provide a convenient environment for the removal of bovine serum albumin (BSA) from BSA and DNA mixtures. The eluent can be used as an efficient tool for detection of DNA biomarkers associated with diagnosis of numerous life‐threatening diseases.
112.
Olfa Hammami Leila Dhouibi Patrice Berçot El Mustafa Rezrazi 《Journal of Applied Electrochemistry》2014,44(1):115-121
Zn–Ni composite coatings were obtained by electrochemical co-deposition of TiO2 nano-particles (mean diameter 21 nm). Zn–Ni alloy coating was also produced under the same experimental conditions for comparison. The surface morphology, crystallographic structure, and the grain size of the deposits were investigated, along with the percentage of the embedded nano-particles in Zn–Ni matrix, as a function of concentration of TiO2 nano-particles in the bath. As the titania incorporation percentage is increased, a grain refinement in the nanometer region was revealed followed enhanced microhardness values and an improvement of the content of the nickel in the alloy. Annealing of all coatings at 200 °C revealed the crystallization of the matrix accompanied by a decrease of microhardness followed by stability for 24 h. The corrosion behavior of Zn–Ni/nano-TiO2 composite coatings with various amount of particle content was mainly studied by electrochemical impedance spectroscopy in 3 % NaCl. It was seen that Zn–Ni/nano-TiO2 composite coatings exhibited higher corrosion resistances comparing to Zn–Ni alloy coating and corrosion protection improved with increasing nano-TiO2 in coatings. 相似文献
113.
Safa Karaman Omer Said Toker Mustafa Çam Mahmut Doğan Ahmed Kayacier 《Drying Technology》2014,32(3):258-267
In this study, the effects of three different drying methods (freeze drying, oven drying, and vacuum oven drying) on bioactive (total phenolics, total flavonoids, condensed tannin and total hydrolyzable tannin contents, antiradical activity, and antidiabetic activity) and some physicochemical (dry matter, ash, water activity (a w ), color, protein, hydroxymethylfurfural, glucose and fructose content) properties of persimmon fruit were investigated. Simplex lattice mixture design methodology was applied to determine the best solvent mixture for the extraction of phenolics from the samples. It was found that the mixture of acetone:water at the ratio of 50:50 % (v/v) was the best solvent mixture for the extraction. The persimmon powder sample obtained from freeze drying showed significantly (p <0.05) higher bioactivity values than oven- and vacuum-oven-dried samples. Antiradical activity changed significantly depending on the drying method employed and it was superior in freeze-dried samples than that of the other drying methods. 相似文献
114.
115.
CAD-oriented analytic formulas are presented for calculating the quasistatic TEM parameters of the overlayed supported asymmetric coplanar waveguides (OSACPW). The effect of the thicknesses and the dielectric constants of the overlaying and supporting materials on the quasistatic parameters has been investigated by using the expressions derived by the conformal mapping techniques. Comparisons have also been made between this article's results and the results available in the literature for the conventional coplanar waveguide (CPW) and the asymmetric coplanar waveguide (ACPW). It has been shown that the present formulas can also be used for calculating the quasistatic TEM parameters of the line structures such as the open, the open supported, and the overlayed supported CPW or ACPW. © 1996 John Wiley & Sons, Inc. 相似文献
116.
Astrid Ahlinder Tiziana Fuoco Álvaro Morales-López Mohammed A. Yassin Kamal Mustafa Anna Finne-Wistrand 《应用聚合物科学杂志》2020,137(15):48550
Although additive manufacturing through melt extrusion has become increasingly popular as a route to design scaffolds with complex geometries the technique if often limited by the reduction in molecular weight and the viscoelastic response when degradable aliphatic polyesters of high molecular weight are used. Here we use a melt extruder and fused filament fabrication printer to produce a reliable nondegradative route for scaffold fabrication of medical grade copolymers of L-lactide, poly(ε-caprolactone-co-L-lactide), and poly(L-lactide-co-trimethylene carbonate). We show that degradation is avoided using filament extrusion and fused filament fabrication if the process parameters are deliberately chosen based upon the rheological behavior, mechanical properties, and polymer composition. Structural, mechanical, and thermal properties were assessed throughout the process to obtain comprehension of the relationship between the rheological properties and the behavior of the medical grade copolymers in the extruder and printer. Scaffolds with a controlled architecture were achieved using high-molecular-weight polyesters exhibiting a large range in the elastic response causing negligible degradation of the polymers. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48550. 相似文献
117.
Thermally exfoliated graphene oxide reinforced fluorinated pentablock poly(l‐lactide‐co‐ε‐caprolactone) electrospun scaffolds: Insight into antimicrobial activity and biodegradation 下载免费PDF全文
Burcu Saner Okan Azucena Marset Jamal Seyyed Monfared Zanjani Pınar Akkus Sut Ozlem Sen Mustafa Çulha Yusuf Menceloglu 《应用聚合物科学杂志》2016,133(22)
Three‐dimensional fluorinated pentablock poly(l ‐lactide‐co‐ε‐caprolactone)‐based scaffolds were successfully produced by the incorporation of thermally exfoliated graphene oxide (TEGO) as an antimicrobial agent with an electrospinning technique. In a ring‐opening polymerization, the fluorinated groups in the middle of polymer backbone were attached with a perfluorinated reactive stabilizer having oxygen‐carrying ability. The fiber diameter and its morphologies were optimized through changes in TEGO amount, voltage, polymer concentration, and solvent type to obtain an ideal scaffold structure. Instead of the widely used graphene oxide synthesized by Hummer's method, TEGO sheets having a low amount of oxygen produced by thermal expansion were integrated into the fiber structure to investigate the effect of the oxygen functional groups of TEGO sheets on the degradation and antimicrobial activity of the scaffolds. There was no antimicrobial activity in TEGO‐reinforced scaffolds in the in vitro tests in contrast to the literature. This study confirmed that a low number of oxygen functional groups on the surface of TEGO restricted the antimicrobial activity of the fabricated composite scaffolds. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43490. 相似文献
118.
Mustafa Tutak 《Coloration Technology》2011,127(5):340-345
In this study, the effect of cationisation on optical whitening was examined. For this purpose, the whiteness index and whiteness tint of optically whitened pre‐cationised knitted cotton fabrics were analysed. The cationisation and optical whitening processes were carried out under different concentration levels, using the exhaustion method. The whiteness index and whiteness tint were calculated after colour measurements were taken. The experimental results were also analysed statistically using ANOVA. The whiteness index obtained from cationised fabric was lower than that of non‐cationised fabrics. While the whiteness tint of cationised cotton fabric had a blue to greenish nuance, the non‐cationised fabric had a reddish nuance. 相似文献
119.
Seed oils of Origanum onites L. from the Antalya and Mugla regions and O. vulgare L. from the Kirklareli region of Turkey were extracted with hexane in a Soxhlet apparatus. The oil yields were 14.1–20.0
and 18.5%, respectively. FA compositions of the seed oils were determined by GC and GC/MS. Twenty FA were identified in both
O. onites and O. vulgare seeds. The major FA of both species were linolenic (56.3–57.0%; 61.8%), linoleic (21.5–21.7%; 18.8%), oleic (8.7–8.9%; 5.9%),
palmitic (5.9–6.5%; 5.5%), stearic (2.1–2.4%; 2.1%), and (Z)-11-octadecenoic (0.6–0.8%; 0.5%), respectively. 相似文献
120.
Iranian Polymer Journal - Surface of Al2O3 nanoparticles was modified with a silane coupling agent, and aramid fiber-reinforced epoxy nanocomposites were produced using these particles. Three... 相似文献