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111.
Nonlinear Dynamics - Similar to elasticity and viscoelasticity, anelasticity is one of the rheological models of materials. Like the viscoelastic materials, anelastic deformation is time dependent,... 相似文献
112.
Spacecraft flying in a low Earth orbit environment require thermal blankets to provide protection from direct solar heat from the sun. Fluorinated ethylene propylene copolymer is one of the major components of these thermal blankets. In this study, the effect of a simulated low Earth orbit environment on FEP was investigated. UV and VUV degradation of fluorinated ethylene propylene (FEP) copolymer was studied using ESR and XPS. The ESR study revealed the formation of a terminal polymer chain radical. The stability of this radical has been investigated under different environments. An XPS study of FEP film exposed to VUV and atomic oxygen showed that oxidation takes place on the polymer surface. The study revealed also that the percentage of CF2 in the polymer surface decreased with exposure time and the percentage of CF, CF3 and carbon attached to oxygen increased. SEM micrographs of FEP film exposed to VUV and atomic oxygen produced a rough surface with regular undulations similar to sand dunes. © 1998 John Wiley & Sons, Ltd. 相似文献
113.
Rezaei Rasoul Foroughi Mohammad Mehdi Beitollahi Hadi Alizadeh Reza 《Russian Journal of Electrochemistry》2018,54(11):860-866
Russian Journal of Electrochemistry - An electrochemical sensor has been fabricated using ZnO/GR nanocomposite for selective determination of uric acid (UA) in a phosphate buffer solution (PBS, pH... 相似文献
114.
Manh Tran Dinh Nam Nguyen Dang Abdulrahman Gihad Keyany Moradi Rasoul Babazadeh Houman 《Journal of Thermal Analysis and Calorimetry》2020,140(6):2865-2873
Journal of Thermal Analysis and Calorimetry - Computational modeling was employed to scrutinize the nanomaterial influence of flow patterns and thermal treatment within a porous region.... 相似文献
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During the past years, light-driven selective oxidation of various alcohols has attracted increasing attention as a green and eco-friendly manner to convert visible light energy into valuable compounds. In this work, magnetic CoFe2O4/Ce-UiO-66 embedded structure composites are elaborately designed for the photocatalytic oxidation of aliphatic alcohols under visible-light irradiation and aerobic condition at room temperature. The CoFe2O4/Ce-UiO-66 structure was prepared using a simple and fast ultrasound-assisted technique in 60 min at room temperature. As compared with the unmodified CoFe2O4, the embedded composite exhibited better visible-light sensitization performance. The catalyst showed high chemical stability in the reaction conditions and can be recovered quickly and reused for at least five reaction runs in the aerobic oxidation reaction condition. 相似文献
118.
Water‐compatible molecularly imprinted polymer as a sorbent for the selective extraction and purification of adefovir from human serum and urine 下载免费PDF全文
Mojgan Pourfarzib Rasoul Dinarvand Behrouz Akbari‐adergani Ali Mehramizi Hossein Rastegar Maryam Shekarchi 《Journal of separation science》2015,38(10):1755-1762
A molecularly imprinted polymer has been synthesized to specifically extract adefovir, an antiviral drug, from serum and urine by dispersive solid‐phase extraction before high‐performance liquid chromatography with UV analysis. The imprinted polymers were prepared by bulk polymerization by a noncovalent imprinting method that involved the use of adefovir (template molecule) and functional monomer (methacrylic acid) complex prior to polymerization, ethylene glycol dimethacrylate as cross‐linker, and chloroform as porogen. Molecular recognition properties, binding capacity, and selectivity of the molecularly imprinted polymers were evaluated and the results show that the obtained polymers have high specific retention and enrichment for adefovir in aqueous medium. The new imprinted polymer was utilized as a molecular sorbent for the separation of adefovir from human serum and urine. The serum and urine extraction of adefovir by the molecularly imprinted polymer followed by high‐performance liquid chromatography showed a linear calibration curve in the range of 20–100 μg/L with excellent precisions (2.5 and 2.8% for 50 μg/L), respectively. The limit of detection and limit of quantization were determined in serum (7.62 and 15.1 μg/L), and urine (5.45 and 16 μg/L). The recoveries for serum and urine samples were found to be 88.2–93.5 and 84.3–90.2%, respectively. 相似文献
119.
A Highly Sensitive Sensor Based on Reduced Graphene Oxide,Carbon Nanotube and a Co(II) Complex Modified Carbon Paste Electrode: Simultaneous Determination of Isoprenaline,Captopril and Tryptophan 下载免费PDF全文
Nooshin Rajabzadeh Ali Benvidi Mohammad Mazloum‐Ardakani Afsaneh Dehghani Firouzabadi Rasoul Vafazadeh 《Electroanalysis》2015,27(12):2792-2799
This paper describes the development of a reduced graphene oxide (RGO), carbon nanotube (CNT) and Co(II) complex (cobalt(II) bis (benzoylacetone) ethylenediimino) (CBE) modified carbon paste electrode (CPE) for simultaneous determination of isoprenaline (IP), captopril (CAP) and tryptophan (Try). A pair of well‐defined redox peaks of Co(II) complex were obtained through a direct electron transfer between the Co(II) complex and the CPE. The proposed sensor showed very efficient electrocatalytic activity for anodic oxidation of IP in a 0.1 M phosphate buffer solution (pH 7.0). Square wave voltammetry (SWV) exhibited two linear dynamic ranges of 0.125–30.0 µM and 30.0–300.0 µM for IP. The detection limit for IP was found to be 50 nM. The proposed sensor was successfully applied for the determination of IP in real samples such as human blood serum, urine and IP ampoule. 相似文献
120.
Fatemeh Nouroozi Faezeh Farzaneh Minoo Khosroshahi 《Reaction Kinetics and Catalysis Letters》2006,89(1):139-147
Summary It was found that immobilized CoCl2 within nanoreactors of Si-MCM-48 catalyzes the oxidation of 1-octene, styrene, cyclohexene, norbornene, trans-stilbene and trans-2-hexene-1-ol with 35 to 95% conversion and 75 to 100% selectivity to the corresponding epoxides. 相似文献