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181.
Simple design of an aligned transparent biofilm by magnetic particles and its cellular study 下载免费PDF全文
Saeed Heidari K Esmaeil Biazar S. Meysam Seyedbarzegar Nayerehsadat Mousavi Fina Vosoughi Naghmeh Khademi S Fariba Nami Hesam Hosseinkazemi 《先进技术聚合物》2017,28(7):805-810
The aim of this study was to produce aligned biodegradable films. In this study, we used magnetic microparticles and strong magnetic field for orientation of gelatin gels. The samples were evaluated by microscopic analyses and cell culture assays with Schwann cells. Results of structural analyses showed a good arrangement and orientation of films under strong magnetic field with movement of magnetite particles. Cellular experiments showed a good cell adhesion and orientation on the designed films compared with those on unmodified ones. This aligned guide appears to have the right organization for testing in vivo nerve tissue engineering studies. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
182.
S. Rasool Azari Mohammad S. Rahmanifar Maher F. El-Kady Abolhassan Noori Mir F. Mousavi Richard B. Kaner 《Journal of the Iranian Chemical Society》2017,14(12):2579-2590
Aqueous supercapacitors based on neutral solutions have the advantages of high-ionic conductivity, being environmentally friendly, safe, and low cost. However, the operating potential window for most aqueous electrolytes is far lower than that of organic electrolytes that are commonly used in commercial supercapacitors. In this work, we report on the fabrication of a wide potential window, high-energy aqueous asymmetric supercapacitor, without sacrificing power, by using a nanostructured LiMn2O4/reduced graphene oxide (LMO–rGO) nanocomposite. We synthesized the uniformly distributed LMO in the LMO–rGO nanocomposite using a co-precipitation route followed by a low-temperature hydrothermal treatment. In a three-electrode cell setup, the specific capacitance of the LMO–rGO nanocomposite electrode at 1 A/g (1.2 mA/cm2) is 268.75 F/g (258 mF/cm2), which shows a dramatic improvement over the sum of the specific capacitances of pristine LMO (162.5 F/g) and pure rGO (29.94 F/g) electrodes in their relative ratios, when used alone. This finding suggests a synergistic coupling of LMO and rGO in the nanocomposite. We also assembled the LMO–rGO nanocomposite, as the positive electrode, with activated carbon, as the negative electrode, into an asymmetric cell configuration. The device shows an ultra-wide potential window of 2.0 V in a neutral aqueous Li2SO4 electrolyte, with a maximum energy density of 29.6 Wh/kg (which approaches the commercial lead-acid batteries), power density of up to 7408 W/kg, and an excellent cycle life (5% loss after 6000 cycles). These findings confirm that an LMO–rGO nanocomposite is a promising material to meet the demands of real world energy storage. 相似文献
183.
Sayed Zia Mohammadi Hadi Beitollahi Maryam Mousavi 《Russian Journal of Electrochemistry》2017,53(4):374-379
A carbon paste electrode that was chemically modified with 3-(4'-amino-3'-hydroxy-biphenyl-4-yl)-acrylic acid (3,4-AA) was used as a selective electrochemical sensor for the detection of hydroxylamine. Cyclic voltammetry (CV), choronoamperometry (CHA) and square wave voltammetry (SWV) were used to investigate oxidation of hydroxylamine in aqueous solution. Under optimized concentration the electrocatalytic oxidation current peak for hydroxylamine increased linearly with concentration in the range of 0.025–10.0 μM. The detection limits for hydroxylamine was 0.012 μM. Finally, the modified electrode was applied to detection hydroxylamine in water samples. 相似文献
184.
Seyed Mohammad Taghi Gharibzahedi Seyed Hadi Razavi Mohammad Mousavi 《Journal of Dispersion Science and Technology》2013,34(5):614-625
Solubilizing the potent anticancer pigments in nanoemulsion (NE) systems containing 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) is a novel and promising strategy to incorporate them into water-based drug formulations. The concentration effects of sunflower oil (SO, 5.61–17.39% w/w), surfactant mixture of Tween 80 (T80) and Span 20 (S20) (1:1 weight ratio, 3.95–14.05% w/w), and the inclusion complex of HP-β-CD with canthaxanthin (CTX) synthesized by Dietzia natronolimnaea HS-1 (2.61–14.39% w/w) were evaluated to formulate a stable NE using ultrasound-assisted emulsification. The NEs were evaluated regarding droplet size and polydispersity index (span), physical stability, turbidity, and loss of antioxidant activity (LAA). Response surface modeling showed that the NEs containing 12% T80/S20, 8.30% SO, and 12% CTX/HP-β-CD had the lowest droplet size (105.5 nm), span (0.394), droplet growth ratio (0.112), turbidity (0.139), and LAA (9.36%). The predicted values obtained were close to the experimental values, indicating the suitability of the constructed models. Transmission electron microscopy and confocal laser-scanning microscopy also demonstrated that the formed droplets of the NEs produced at optimal formulation were spherical in the range of 20–100 nm. A significant correlation was found between droplet size with stability (r = ?0.960, p < 0.01) and turbidity (r 2 = 0.876, p < 0.01) values. 相似文献
185.
Ebrahimi B Shojaosadati SA Daneshgar P Norouzi P Mousavi SM 《Analytica chimica acta》2011,(2):168-176
In this work, a method for the fast monitoring of OPs in flow-injection systems was evaluated. The fast Fourier transform continuous cyclic-voltammetry (FFTCCV) at the carbon-paste electrode in a flowing solution system was used for determination of OPs. In this method the S/N ratio is enhanced by using of fast Fourier transform of the analyte and signal integration. FFTCCV can be considered as a new sensitive, accurate and fast method for determination of drugs and some pesticides. However, in order to obtain better sensitivity for a specific target, experimental parameters should be optimized. Response surface methodology (RSM) was applied to optimize three effective parameters (enzyme activity, multiwall carbon nanotube quantity and acidic sol–gel quantity). The optimum values for the tested parameters were enzyme amount H0.169 U cm−2, multiwall carbon nanotube (MWCNT) 0.607 mL and acidic sol–gel 1.012 mL. The optimum feed pH, feed flow rate, ATChCl concentration and sweeping-rate were found to be 7.4, 0.34 mL min−1, 0.750 mM and 10 V s−1, respectively. The long-term stability of this flow-through system was 80% of its initial response after 120 days. Based on an incubation time of 12 min, it was found that the detection limit for paraoxon was equal to 1.7 × 10−7 mg L−1 (6.2 × 10−13 M). The developed biosensor exhibited good repeatability and reproducibility. This study provides a new, modern, sensitive tool for the analysis of organophosphate pesticides. 相似文献
186.
Seyyed M. Hasheminejad Sadeq Malakooti Hessam Mousavi Akbarzadeh 《Archive of Applied Mechanics (Ingenieur Archiv)》2011,81(12):1889-1902
An exact study based on the linear theory of elasticity is presented for the steady-state sound radiation characteristics
of an arbitrarily thick radially inhomogeneous elastic isotropic hollow sphere, immersed in and filled with ideal compressible
fluids, and subjected to an arbitrary axisymmetric time-harmonic driving force at its internal surface. A modal state equation
with variable coefficients is set up in terms of appropriate displacement and stress functions and their spherical harmonics
by means of the laminated approximation approach. Taylor’s expansion theorem is subsequently employed to solve the modal state
equation, ultimately calculating a global transfer matrix. Numerical results are presented for a water-submerged/air-filled
steel/zirconia FGM hollow sphere under an axisymmetric distributed internal pressure force. The effects of shell wall thickness,
the material compositional gradient, frequency, and subtended polar angle of the internal pressure force on the far-field
radiated pressure directivity patterns as well as the total radiated power are examined. It is demonstrated that the material
gradient can significantly change the acoustical characteristics of hollow inhomogeneous sphere, especially for thick shells
at high excitation frequencies. Limiting cases are considered and good agreements with available results as well as with the
computations made by using a finite element package are obtained. 相似文献
187.
188.
Mir Rasul Mousavi Nourallah Hazeri Malek Taher Maghsoodlou Sajjad Salahi Sayyed Mostafa Habibi-Khorassani 《中国化学快报》2013,24(5):411-414
Saccharose was applied as an efficient and homogenous catalyst for a one-pot, three-component Mannich reaction for the formation of β-aminoketones from aromatic aldehydes, anilines, and acetophenone at ambient temperature in excellent yields. This protocol has the following advantages: mild conditions, high yields, clean reaction profiles, operational simplicity, and environmentally benign and simple work-up procedures. 相似文献
189.
Saeed Jameh-Bozorghi Davood Nori-Shargh Seiedeh Negar Mousavi Amin Rezaei 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):839-849
Abstract Natural bond orbital (NBO) interpretation and hybrid density functional theory (hybrid-DFT: B3LYP/Def2-TZVPP)-based methods were used to investigate the impacts of the generalized anomeric effects (GAE), electrostatic, and steric interactions on the conformational properties of cis and trans isomers of 2-fluoro-, 2-chloro-, and 2-bromotetrahydrothiopyran S-oxide (1–3). The results obtained showed that the trans-axial configurations are the most stable forms of compounds 1–3. Based on the results obtained, the instability of the second lowest energy-minimum (cis-equatorial configuration, with axial S?O and equatorial C?X bonds, X = halogen atoms) increases from compound 1 to compound 3. This trend is also observed for the third lowest energy-minimum (i.e., the trans-equatorial configuration). Contrary to the trend observed for the cis- and trans-equatorial forms, the instability of the cis-axial form compared to the trans-axial form, increases from 1 to 2 but decreases slightly from 2 to 3. The correlations between the GAE, bond orders, steric effects, ΔG, Δμ, structural parameters, and conformational and configurational behaviors of compounds 1–3 have been investigated. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献
190.
In this work, optical properties of ZnO nanostructures prepared by chemical vapor deposition under different conditions were investigated. ZnO nanostructures were characterized by electron microscopy and photoluminescence. A high intensity green emission and a narrow UV emission band are observed in photoluminescence spectra of ZnO nanostructures related to the below-band-gap and band-edge that their intensities depend on the morphology of the nanostructures. It is considered that the green emission is originated from structural defects. In addition, the influence of thermal treatment and dopants such as iron and copper, on the photoluminescence (PL) properties of the ZnO nanostructures was investigated. 相似文献