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91.
Brahim Aïssa Zéhira Hamoudi Hiro Takahashi Kazuyuki Tohji Mohamed Mohamedi My Ali El Khakani 《Electrochemistry communications》2009,11(4):862-866
We report the first direct laser based synthesis of carbon nanohorns onto carbon microfibrous, for the straightforward fabrication, of free-standing (binderless) electrodes. These carbon nanohorns have diameters as small as 2–4 nm and were found to cover uniformly the microfibrous substrates. The carbon nanohorns-based electrodes developed here are shown to open new prospects for the development of advanced electrochemical power sources. In particular, their possible applications in either lithium-ion batteries or supercapacitors or fuel cell technologies are demonstrated. 相似文献
92.
A novel Zn(II) ions imprinted poly (2-hydroxyethyl Methacrylate-N-methacryloyl-(L)-histidine methyl ester) poly(HEMAH) surface plasmon resonance (SPR) nanosensor were designed for detection of Zn(II) ions in aqueous solution and artificial plasma providing a low cost, rapid and reliable results compared to other techniques such as atomic absorption spectroscopy, inductively coupled plasma-mass spectrometer, X-ray fluorescence with synchrotron radiation. Zn(II) ions imprinted nanofilm on the SPR chip surface was synthesized by bulk polymerization. Characterization of Zn(II) ions imprinted nanosensor was performed by contact angle measurement, atomic force microscopy (AFM), ellipsometry and Fourier transform infrared spectroscopy-attenuated total reflection (FTIR-ATR). Designed nanosensor was applied for selective detection of Zn(II) ions in aqueous solution within the range of 0.5–1.0?µg/mL. The limit of detection (LOD) and limit of quantification (LOQ) were calculated as 0.19 and 0.64?ng/mL, respectively. Association kinetics analysis, Scatchard, Langmuir, Freundlich, Langmuir–Freundlich, Tempkin and Dubinin-Radushkevich isotherms were analyzed to the experimental data in order to identify the adsorption behavior. The selectivity of the SPR nanosensor was examined by using competitive metal ions such as Cd(II), Cu(II), Pb(II), and Fe(II). To evaluate the imprinting effect of Zn(II) ions imprinted (MIP) and non-imprinted (NIP) nanosensor was also prepared as the control. Repeatability of the response signal was tested by four times adsorption–desorption–regeneration cycle. 相似文献
93.
The problem of estimating the Markov renewal matrix and the semi-Markov transition matrix based on a history of a finite semi-Markov
process censored at time T (fixed) is addressed for the first time. Their asymptotic properties are studied. We begin by the definition of the transition
rate of this process and propose a maximum likelihood estimator for the hazard rate functions and then we show that this estimator
is uniformly strongly consistent and converges weakly to a normal random variable. We construct a new estimator for an absolute
continous semi-Markov kernel and give detailed derivation of uniform strong consistency and weak convergence of this estimator
as the censored time tends to infinity.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
94.
An improved microwave Clevenger apparatus for distillation of essential oils from orange peel 总被引:5,自引:0,他引:5
Microwave Clevenger or microwave accelerated distillation (MAD) is a combination of microwave heating and distillation, performed at atmospheric pressure without added any solvent or water. Isolation and concentration of volatile compounds are performed by a single stage. MAD extraction of orange essential oil was studied using fresh orange peel from Valencia late cultivar oranges as the raw material. MAD has been compared with a conventional technique, which used a Clevenger apparatus with hydro-distillation (HD). MAD and HD were compared in term of extraction time, yields, chemical composition and quality of the essential oil, efficiency and costs of the process. Extraction of essential oils from orange peels with MAD was better in terms of energy saving, extraction time (30 min versus 3 h), oxygenated fraction (11.7% versus 7.9%), product yield (0.42% versus 0.39%) and product quality. Orange peels treated by MAD and HD were observed by scanning electronic microscopy (SEM). Micrographs provide evidence of more rapid opening of essential oil glands treated by MAD, in contrast to conventional hydro-distillation. 相似文献
95.
Brahim Gaboune Gilbert Laporte François Soumis 《The Journal of the Operational Research Society》1993,44(5):513-519
In this paper, the expected distance between two uniformly distributed random points in a rectangle or in a rectangular parallelepiped is computed under three different metrics: the Manhattan metric, the Euclidean metric, and the Chebychev metric. 相似文献
96.
A new formulation is proposed to describe immiscible compressible two-phase flow in porous media. The main feature of this formulation is the introduction of a global pressure. The resulting equations are written in a fractional flow formulation and lead to a coupled system which consists of a nonlinear parabolic (the global pressure equation) and a nonlinear diffusion–convection one (the saturation equation) which can be efficiently solved numerically. To cite this article: B. Amaziane, M. Jurak, C. R. Mecanique 336 (2008). 相似文献
97.
A similarity analysis was performed to investigate the laminar boundary-layer flow in the presence of a transverse magnetic
field over a down-pointing and spinning cone with mixed thermal boundary conditions. Boundary layer velocity and temperature
profiles were determined numerically for various values of the magnetic and spin parameters and the Prandtl number. The spin
of the cone compresses the velocity profiles towards the surface by inducing an upward flow and decreases the surface temperature.
The magnetic field suppresses the velocity profiles and increases the surface temperature. A transformation relating the similarity
solutions of the boundary-layer velocity and temperature profiles associated with different values of the mixed thermal boundary
condition parameter was obtained. 相似文献
98.
Bozkir Cem Deniz Caglar Kundakcioglu O. Erhun Henry Andrea C. 《Journal of Global Optimization》2022,83(3):565-584
Journal of Global Optimization - In this study, we consider a health network that faces uncertain supply disruptions in the form of regional, nationwide, or worldwide drug shortages. Each hospital... 相似文献
99.
Murat Celtek Sedat Sengul Unal Domekeli Cem Canan 《The European Physical Journal B - Condensed Matter and Complex Systems》2016,89(3):65
In this study, the temperature effects on the structural evolution of theZr70Pd30 binary alloy in the glassy and liquid states werestudied using the molecular dynamics simulations based on the many-body type tight-bindingpotential. We considered the following properties in detail: the temperature dependence ofthe volume, the partial and total pair distribution functions and the simulated glasstransition temperature. The effects of the cooling rates on the glass transitiontemperature were examined. The Wendt-Abraham parameter was calculated to determine theglass transition temperature of Zr70Pd30 glassy alloy. The pair analysis technique ofHoneycutt-Andersen was applied to define local atomic arrangements produced from moleculardynamics simulations. The results show that the icosahedral ordering in glassy state hasbeen composed during quenching period, and the simulated glass transition temperature andthe total pair distribution functions are in good agreement with the experimental data. 相似文献
100.
Many studies suggest strong hydrophilicity of plasma treated polyester surfaces. However, no studies have been reported on
the influence of plasma on the antibacterial activity of polyethylene terephthalate. First samples were padded with triclosan
as antibacterial agent with different concentrations. Second samples were treated by oxygen plasma with different operating
frequency and treating time, respectively. Afterwards, plasma treated samples were padded with triclosan in same conditions.
The results revealed that the antibacterial activity slighlty increased after treating with triclosan. SEM images and FTIR
spectra showed that horizontal channels were brought about on the fiber surface and then better surface roughness and wettability
were obtained by plasma. Fibers were fully coated with triclosan after plasma and the antibacterial activity increased with
increasing operating frequency and reaction time. Finally, the samples treated with triclosan after plasma gave acceptable
results and showed the best antibacterial activity for Staphylococcus aureus and Escherichia coli. 相似文献