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101.
In the present work, vibrational and thermodynamic properties of XBi(X = B, Al, Ga, In) compounds are compared and investigated. The calculation is carried out using density functional theory(DFT) within the generalized gradient approximation(GGA) in a plane wave basis, with ultrasoft pseudopotentials. The lattice dynamical properties are calculated using density functional perturbation theory(DFPT) as implemented in Quantum ESPRESSO(QE) code. Thermodynamic properties involving phonon density of states(DOS) and specific heat at constant volume are investigated using quasiharmonic approximation(QHA) package within QE. The phonon dispersion diagrams for InBi, GaBi, BBi, and AlBi indicate that there is no imaginary phonon frequency in the entire Brillouin zone, which proves the dynamical stability of these materials. BBi has the highest thermal conductivity and InBi has the lowest thermal conductivity. AlBi has the largest and GaBi has the smallest reststrahlen band which somehow suggests the polar property of XBi materials. The phonon gaps for InBi, GaBi, BBi and AlBi are about 160 cm~(-1), 150 cm~(-1), 300 cm~(-1), and 150 cm~(-1), respectively. For all compounds,the three acoustic modes near the gamma point have a linear behavior. C_V is a function of T~3 at low temperatures while for higher temperatures it asymptotically tends to a constant as expected.  相似文献   
102.
The importance of applying DNA sequencing in different fields, results in looking for fast and cheap methods. Nanotechnology helps this development by introducing nanostructures used for DNA sequencing. In this work we study the interaction between zigzag silicene nanoribbon and DNA nucleobases using DFT and non equilibrium Green's function approach, to investigate the possibility of using zigzag silicene nanoribbons as a biosensor for DNA sequencing.  相似文献   
103.
NiAl2O4 spinel nanocrystals were synthesized as mesoporous catalysts and were fully characterized using Fourier‐transform infrared spectroscopy (FT‐IR), X‐ray diffraction patterns (XRD), scanning electron microscopy (SEM), and Energy‐dispersive X‐ray spectroscopy (EDS). These nanocrystals catalyzed the synthesis of 2,3‐dihydroquinazolin‐4(1H)‐one derivatives via a one‐pot, three‐component condensation reaction of aromatic aldehydes, isatoic anhydride, and ammonium acetate or primary aromatic amine under microwave irradiation. By far, the most obvious advantages of the offered process are efficiency and recyclability of the catalyst as well as a significantly shorter reaction time.  相似文献   
104.
Nickel oxide nanoparticle (NiO?NP) and polypyrrole (PPy) composite were deposited on a Pt electrode for fabrication of a urea biosensor. To develop the sensor, a thin film of PPy?NiO composite was deposited on a Pt substrate that serves as a matrix for the immobilization of enzyme. Urease was immobilized on the surface of Pt/PPy?NiO by a physical adsorption. The response of the fabricated electrode (Pt/PPy?NiO/Urs) towards urea was analyzed by chronoamperometry and cyclic voltammetry (CV) techniques. Electrochemical response of the bio‐electrode was significantly enhanced. This is due to electron transfer between Ni2+ and Ni3+ as the electro‐catalytic group and the reaction between polypyrrole and the urease‐liberated ammonium. The fabricated electrode showed reliable and demonstrated perfectly linear response (0.7–26.7 mM of urea concentration, R2= 0.993), with high sensitivity (0.153 mA mM?1 cm?2), low detection of limit (1.6 μM), long stability (10 weeks), and low response time (~5 s). The developed biosensor was highly selective and obtained data were repeatable and reproduced using PPy‐NiO composite loaded with immobilized urease as urea biosensors.  相似文献   
105.
Spherical spline quaternion interpolation has been done on sphere in Euclidean space using quaternions. In this paper, we have done the spline split quaternion interpolation on hyperbolic sphere in Minkowski space using split quaternions and metric Lorentz. This interpolation curve is called spherical spline split quaternion interpolation in Minkowski space (MSquad).  相似文献   
106.
The aim of this paper is to propose an integrated model for resource planning in power systems by taking into account both supply and demand sides options simultaneously. At supply-side, investment in generation capacity and transmission lines is considered. Demand side management (DSM) technologies are also incorporated to correct the shape of the load duration curve in terms of peak clipping and load shifting programmes. A mixed integer non-linear programming model is developed to find the optimal location and timing of electricity generation/transmission as well as DSM options. To solve the resulting complex model, nonlinearity caused by transmission loss terms are first eliminated using the piecewise linearization technique. Then, a Benders decomposition (BD) algorithm is developed to solve the linearized model. The performance of the proposed BD algorithm is validated via applying it to the 6-bus Garver test system and a modified 21-bus IEEE reliability test system.  相似文献   
107.
We present a simple methodology to illustrate the existence of tetraphenylporphyrin monoacid based on ion-transfer voltammetry at a polarized water|1,2-dichloroethane interface and organic pK values are also estimated.  相似文献   
108.
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