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11.
Aqueous solutions of the water-soluble porphyrin 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrinatomanganese(III) acetate were inserted into the holes of a photonic crystal fiber, and the porphyrin absorption bands were identified. Results were obtained for three concentrations. The porphyrins in water show no surface interactions with the silica walls of the capillary channels. We discuss the implications for future hybrid electronic and photonic fiber devices. 相似文献
12.
Danial Khojasteh Alireza Bordbar Marco Marengo 《International Journal of Computational Fluid Dynamics》2017,31(6-8):310-323
Droplet impact on hydrophobic and superhydrophobic solid surfaces finds numerous applications, while the wide range of the parameters affecting its outcome necessitate a thorough study to reveal the underlying physics. Specific applications are related to the drop impact upon curved surfaces, such as micro-encapsulation in fluidized beds. Three-dimensional numerical simulations by applying Level-Set Method have been performed to investigate the water droplet impact on curved and flat hydrophobic and superhydrophobic substrates. Parameters such as the impact Weber number, the surface curvature and the equilibrium contact angle have been varied in order to assess their effects on the dynamics of the impact process. After providing a strong validation, it is found that impact on spherical surfaces generally presents a higher area of liquid to be in contact with the substrate with respect to the case of flat surfaces, when all other impact conditions are the same. 相似文献
13.
In this work, the effect of the material microstructural interface between two materials (i.e., grain boundary in polycrystalls) is adopted into a thermodynamic-based higher order strain gradient plasticity framework. The developed grain boundary flow rule accounts for the energy storage at the grain boundary due to the dislocation pile up as well as energy dissipation caused by the dislocation transfer through the grain boundary. The theory is developed based on the decomposition of the thermodynamic conjugate forces into energetic and dissipative counterparts which provides the constitutive equations to have both energetic and dissipative gradient length scales for the grain and grain boundary. The numerical solution for the proposed framework is also presented here within the finite element context. The material parameters of the gradient framework are also calibrated using an extensive set of micro-scale experimental measurements of thin metal films over a wide range of size and temperature of the samples. 相似文献
14.
Sliding observer for synchronization of fractional order chaotic systems with mismatched parameter 总被引:1,自引:0,他引:1
Hadi Delavari Danial M. Senejohnny Dumitru Baleanu 《Central European Journal of Physics》2012,10(5):1095-1101
In this paper, we propose an observer-based fractional order chaotic synchronization scheme. Our method concerns fractional order chaotic systems in Brunovsky canonical form. Using sliding mode theory, we achieve synchronization of fractional order response with fractional order drive system using a classical Lyapunov function, and also by fractional order differentiation and integration, i.e. differintegration formulas, state synchronization proved to be established in a finite time. To demonstrate the efficiency of the proposed scheme, fractional order version of a well-known chaotic system; Arnodo-Coullet system is considered as illustrative examples. 相似文献
15.
A Si(111) surface has been derivatized with a thiophene-terminated alkyl monolayer which was subsequently photoanodically oxidized in the presence of thiophene to yield a strongly adherent and smooth conducting film. 相似文献
16.
Fabrication of Nickel Tetrasulfonated Phthalocyanine Functionalized Multiwalled Carbon Nanotubes on Activated Glassy Carbon Electrode for the Detection of Dopamine 下载免费PDF全文
Chelladurai Karuppiah Rajkumar Devasenathipathy Shen‐Ming Chen Danial Arulraj Selvakumar Palanisamy Veerappan Mani V. S. Vasantha 《Electroanalysis》2015,27(2):485-493
The nickel tetrasulfonated phthalocyanine (NiTsPc) functionalized multiwalled carbon nanotube (MWCNT) nanocomposite was prepared by a simple sonochemical method. Here, NiTsPc served as a dispersing agent for MWCNT via π? π interaction between MWCNT and NiTsPc. The activated glassy carbon electrode (AGCE) modified with MWCNT‐NiTsPc composite exhibited a good electrocatalytic ability toward dopamine and displayed a good linear dependence in the concentration range of 20 nM–1.384 mM with a sensitivity of 0.17 µA µM?1 cm?2. The detection limit is 1 nM based on the signal‐to‐noise ratio of 3. 相似文献
17.
A Simple and Highly Sensitive Electrochemically Reduced p‐Nitrobenzoic Acid Film Modified Sensor for Determination of Mercury 下载免费PDF全文
Herein, a simple electrochemical sensor was fabricated for sensing Hg2+ ions by using electrochemically reduced p‐nitrobenzoic acid molecules modified (ERpNBA) glassy carbon electrode (GCE). The modified electrode was applied for the determination of Hg2+ ions by using differential pulse anodic stripping voltammetry (DPASV). Experimental parameters such as concentration of p‐nitrobenzoic acid used for electrode modification, pH, accumulation time and deposition potential used for the determination of Hg2+ ions were optimized. The strong interaction between the Hg2+ ions and the lone pair of electrons on the nitrogen atoms of ERpNBA molecules leads to highly selective adsorption of Hg2+ ions on the modified electrode. Under the optimum experimental conditions, the sensor showed higher sensitivity and very low detection limit for Hg2+ ions than other metal ions such as Cd2+, Pb2+ and Zn2+ ions. The LOD for Hg2+ ions was 240 pM which is below the guideline value given by the World Health Organization and the earlier reports. 相似文献
18.
A. Szytu?a ?. Gondek A. Arulraj B. Penc 《Journal of magnetism and magnetic materials》2009,321(20):3402-3405
Physical properties of NdAu2Ge2, crystallising with the tetragonal ThCr2Si2-type crystal structure, were investigated by means of magnetic, calorimetric and electrical transport measurements as well as by neutron diffraction. The compound exhibits antiferromagnetic ordering below TN=4.5 K with a collinear magnetic structure of the AFI-type. The neodymium magnetic moments are parallel to the c-axis and amount to 1.04(4) μB at 1.5 K. The observed magnetic behaviour is strongly influenced by crystalline electric field effect. 相似文献
19.
Heidar Raissi Farzaneh Farzad Emad Saleh Nadim Mehdi Yoosefian Hossein Farsi Alireza Nowroozi Danial Loghmaninejad 《International journal of quantum chemistry》2012,112(5):1273-1284
We report an investigation on intermolecular interactions in R? CN ··· H? OCH3 (R = H, CH3, F, Cl, NO2, OH, SH, SCH3, CHO, COCH3, CH2Cl, CH2F, CH2OH, CH2COOH, CF3, SCOCH3, SCF3, OCHF2, CH2CF3, CH2OCH3, and CH2CH2OH) complexes using density functional theory. The calculations were conducted on B3LYP/6‐311++G** level of theory for optimization of geometries of complexes and monomers. An improper hydrogen bonding (HB) in the H3CO? H ··· NC? R complexes was observed in that N atom of the nitriles functions acts as a proton acceptor. Furthermore, quantum theory of “Atoms in Molecules” (AIM) and natural bond orbital (NBO) method were applied to analyze H‐bond interactions in respective complexes. The electron density (ρ) and Laplacian (?2ρ) properties, estimated by atoms in molecules calculations, indicate that H ··· N bond possesses low ρ and positive ?2ρ values, which are in agreement with partially covalent character of the HBs, whereas O? H bonds have negative ?2ρ values. In addition, the weak intermolecular force due to dipole–dipole interaction (U) is also considered for analysis. The examination of HB in these complexes by quantum theory of NBO method fairly supports the ab initio results. Natural population analysis data, the electron density, and Laplacian properties, as well as, the ν(O? H) and γ(O? H) frequencies of complexes, calculated at the B3LYP/6‐311++G** level of theory, are used to evaluate the HB interactions. The calculated geometrical parameters and conformational analysis in water phase solution show that the H3CO? H ··· NC? R complexes in water are more stable than that in gas phase. The obtained results demonstrated a strong influence of the R substituent on the properties of complexes. Numerous correlations between topological, geometrical, thermodynamic properties, and energetic parameters were also found. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012 相似文献
20.
Mahale RY Arulkashmir A Dutta K Krishnamoorthy K 《Physical chemistry chemical physics : PCCP》2012,14(13):4577-4583
The impact of electron transfer (ET) from a series of band edge modulated polymers to atmospheric oxygen is examined in connection with substrate oxidation prevention. Polymers with the highest occupied molecular orbital (HOMO) energy level below and above the oxygen energy level were tested and the former showed better efficiency. Furthermore, the oxidation prevention efficiency of a polymer with lower HOMO increased by two orders of magnitude, when the pores on the film were filled with spherical molecules, [6,6]-phenyl-C61-butyric acid methyl ester. We found that the polymer surface hydrophobicity has little or no influence on oxidation prevention. It is interesting to note that a polymer with a hole mobility of 8 × 10(-10) cm(2) V(-1) s(-1) showed a two-fold increase in oxidation prevention efficiency compared to a polymer with a hole mobility of 6 × 10(-5) cm(2) V(-1) s(-1). Over all, from the concerted approach, we conclude that a polymer devoid of pores with the HOMO energy level below oxygen and low charge carrier mobility is a suitable candidate for prevention of substrate oxidation/corrosion. 相似文献