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141.
142.
143.
Hadi Fallah Moafi Abdollah Fallah Shojaie Mohammad Ali Zanjanchi 《Journal of Thermal Analysis and Calorimetry》2011,104(2):717-724
We have investigated the effect of titanium dioxide as a durable finish on the flammability and photocatalytic self-cleaning
of cellulosic fabric. Nano-sized titanium dioxide particles were successfully synthesized and deposited onto cellulosic fibers
with good compatibility, significant photocatalytic self-cleaning activity, and flame-retardancy properties using the sol–gel
process at low temperature. The photocatalytic activity was tested by measuring the photodegradation of methylene blue under
ultraviolet–visible illumination, and also flame-retardancy effect was tested by flammability tester. The samples have been
characterized by several techniques such as scanning electron microscopy, transmission electron microscopy, diffuse reflectance
spectroscopy, X-ray diffraction, and thermogravimetric analysis. The titanium dioxide nanoparticles with 10–20 nm in size
have been found to form a homogeneous thin film on the fiber surface which shows efficient photocatalytic and flame-retardancy
properties. This preparation technique can also be applied to new fabrics to create self-cleaning and flame-retardancy properties
in them. 相似文献
144.
In the current study, the interaction between L-dopa and bovine serum albumin (BSA) as well as catechol and BSA is investigated separately. In order to achieve the optimum values for encapsulated efficiency (EE), the content of crosslinker/BSA, organic/aqueous phase, drug/BSA, stirring rate, and pH were closely studied taking the advantage of Taguchi method. Particle characterization was carried out using transmission electron microscopy and dynamic light scattering techniques. The most appropriate catechol and L-dopa nanoparticles in the size range of 100 nm and 65 nm, respectively, and at optimized conditions of drug/BSA = 0.1, pH = 7.4, crosslinker/BSA = 0.084, organic/aqueous phase = 4 and stirring rate 400 rpm were obtained. The most favorable EE (encapsulation efficiency) and LC (loading capacity) for L-dopa and catechol was estimated to be 88.1% and 83.6%, respectively, and the calculated LC% was achieved 93.4% and 89.7% for L-dopa and catechol, respectively. The chromatographic analyses results were also found to be in a good agreement with the obtained data for the calculated EE% and LC% values. in vitro release of loaded drugs from nanoparticles in phosphate-buffered saline (pH = 7.4, incubated at 37 ± 0.5°C under stirring rate of 100 rpm) showed the release of 78% catechol and 89% L-dopa during 480 min and 510 min, respectively. 相似文献
145.
Polypyrrole (PPy) coatings were synthesized on copper by electrochemical polymerization of pyrrole monomer in aqueous acidic and basic solutions by cyclic voltammetry. The coatings were characterized with CV, UV-visible absorption spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, and scanning electron microscopy (SEM) techniques. The corrosion protection aspects of PPy coatings have been investigated using the potentiodynamic polarization technique and electrochemical impedance spectroscopy (EIS). The potentiodynamic polarization measurements show that the PPy coating has ability to protect the copper against corrosion. It was concluded that a complete corrosion protective PPy film could not be obtained through direct electro-oxidation procedure. This may be due to copper dissolution in the monomer oxidation potential range. 相似文献
146.
Abdollah Omrani Abbas Ali Rostami Fatemeh Ravari 《Journal of Thermal Analysis and Calorimetry》2013,111(1):677-683
The decomposition kinetics of glycerol diglycidyl ether (GDE)/3,3-dimethylglutaric anhydride/nanoalumina composite have been investigated by thermogravimetry analysis under nonisothermal mode. The activation energy, E a, of the solid-state decomposition process was evaluated using the advanced isoconversional method. From the experimental data, the dependence of conversion on temperature and activation energy was constructed allowing calculating the master plots. Our results showed that the decomposition mechanism at temperatures below 400 °C could be fitted by R2 kinetic model with E a = 143 kJ mol?1. The information about the kinetic parameters based only on thermal degradation data has been used for quick lifetime estimation at different temperatures. The Vyazovkin method was also employed to predict the times to reach α = 0.5 at isothermal mode using the activation energy calculated by the advanced isoconversional approaches. Scanning electron microscopy (SEM) analysis was carried out to investigate the fracture surface morphology. It was revealed from the SEM images that the presence of nanoalumina results in reinforcement of GDE matrix. 相似文献
147.
Potential cycling in the range from -0.2 to +1.2 V is used for the electrodeposition of hydrous iridium oxide films onto a screen-printed electrode from a saturated solution of alkaline iridium(III) solution. The iridium oxide redox couple shows a stable and obvious reversible redox, with the formal potential being pH dependent in the range 1-14. The properties, stability and electrochemical properties of iridium oxide films were investigated by cyclic voltammetry. A modified electrode showed excellent catalytic activity toward the oxidation of neurotransmitters (catecholamines) over a wide pH range (2-8). The electrocatalytic behavior is further exploited as a sensitive detection scheme for adrenaline and dopamine by hydrodynamic amperometry. Under the optimized conditions, the calibration curves are linear in the concentration range 0.1-70 and 0.1-15 microM for dopamine and adrenaline determination, respectively. The detection limit and sensitivity are 30 nM and 30 nA/microM for adrenaline and 15 nM and 80 nA/microM for dopamine. Finally, the analytical performance of the modified electrode was demonstrated for the elimination of interference by uric acid in catecholamines determination when present in a 1000-fold concentration excess. 相似文献
148.
Mohammad Hossein Habibi Shahram Tangestaninejad Abdollah Fallah‐Shojaie Iraj Mohammadpoor‐Baltork Reza Mokhtari Neil R. Brooks William Clegg 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(11):m494-m495
The molecule of the title compound, [Hg(C13H9N2O2S)2], has approximate twofold rotation symmetry, with the Hg atom in an essentially linear two‐coordinate HgS2 environment supported by secondary π interactions with the nitrophenyl rings of both ligands. The ligands are in the imine–thiolate rather than the amine–thione tautomeric form. 相似文献
149.
Synthesis of some novel fused oxo‐ and thiopyrimidines via an intramolecular friedel‐crafts reaction
Akbar Mobinikhaledi Naser Foroughifar Abdollah Javidan Ehsan Amini 《Journal of heterocyclic chemistry》2007,44(3):557-559
150.
Mohammad Hossein Tavakoli Ebrahim Mohammadi-Manesh Abdollah Ojaghi 《Journal of Crystal Growth》2009,311(17):4281-4288
A series of 2D finite element numerical simulations of induction heating process for an oxide Czochralski crystal growth system has been done for different shapes and locations of a metal crucible. Comparison between the computational results shows the importance of crucible shape, geometry and its position with respect to the RF-coil on the electromagnetic field and heat generation distribution in the growth setup. 相似文献