Hirata, Hiro-HitoGhosh, SwapanO'Connor, Charmian J.Furusaka, Michihiro...
5页查看更多>>摘要：The lamellar structure of an extremely anti-symmetric bi-tail-type surfactant "barium ethyl (n-octyl)phosphate Ba (EOP)(2)" in D2O was investigated by the SANS method. The SANS intensity spectra were analyzed, based on a one-dimensional paracrystal model with uniaxial randomly oriented stacks. The results provided the lamellar model in which the ethyl and n-octyl chains are closely packed in a tail-to-tail manner which alternately combines the short and long n-alkyl chains. The closely-packed lamella was ascribed to the coordination effect of Ba2+ to the two PO4- groups of the EOP surfactants, as a result of comparison with the x-ray low angle diffraction consequence of "a loosely packed lamellar model" of Li (EOP) (already reported by Hirata et al. [1]).
原文链接:
NSTL
Elsevier
Rumyantsev, V. V.Paladyan, Yu A.Fedorov, S. A.Gumennyk, K., V...
5页查看更多>>摘要：ABS T R A C T The paper employs mathematical modeling to elucidate the specifics of propagation of electromagnetic excita-tions through a non-ideal one-dimensional photonic crystal. We focus on such key quantities as the refractive index and the width (energy gap) of the lowest forbidden band in the energ y spectrum and study their depen-dence on concentrations of point and layer structural defects (the layers are allowed to va r y in their compositions and thicknesses).
原文链接:- NSTL
- Elsevier
Jain, AditiShrivastava, DeepikaKurchania, Rajnish
8页查看更多>>摘要：Structural, electronic, elastic, vibrational and thermoelectric properties of HfCu2In Heusler-structured intermetallic compound in MnCu2Al-type structure with space group Fm-3m has been studied by using ab-initio density functional theory for the first time. The calculated band structure shows the metallic nature of the compound. HfCu2In is ductile which was affirmed by the computed values of the Poisson's ratio, Cauchy's pressure and Pugh's ratio. Thermoelectric properties such as electrical conductivity, Seebeck-coefficient, electronic thermal conductivity and power factor are measured with the BoltzTrap software. The calculated phonon dispersion curve contains positive frequencies in all symmetric directions in the first Brillouin zone, indicating the dynamical stability of the compound in a cubic MnCu2Al-type structure. Furthermore, near the zone center, Raman and infrared phonon modes for alloy have been explored, indicating that the estimated phonon spectra are accurate. The present calculated results are compared with those of the other Heusler alloys of a similar type.
原文链接:- NSTL
- Elsevier
Tiwari, AradhanaSahay, P. P.
10页查看更多>>摘要：In this paper, the modification in the physical properties of spin-coated ZnO thin films upon Sn/Ni co-doping has been presented. All the films possess the hexagonal wurtzite structure of ZnO with varying surface morphologies. Among all the films, the optical transmittance beyond 550 nm wavelength is maximum for the 1 at% Ni-doped ZnO (1NZO) and (1 at% Sn + 1 at% Ni) co-doped ZnO (1T1NZO) films. The optical band gap for the pristine ZnO film is 3.26 eV, which decreases upon doping and co-doping. The PL spectra of the films exhibit the UV emission corresponding to excitonic transitions and the blue and green emissions related to native defects in the ZnO structure. The room-temperature electrical conductivity is found maximum in the 1T1NZO film. The existence of 1T1NZO film with improved optical transmittance and high electrical conductivity supports its use in transparent conductive oxide applications.
原文链接:- NSTL
- Elsevier
PriyankaSharma, RinkuKumar, Manoj
9页查看更多>>摘要：There is a need to get familiarized with a systematic and precise approach to study the energy dispersion and ballistic conductance in a Ga1-xAlxAs quantum wire. We have employed parabolic confinement in this work. The combined impacts of Rashba spin orbit interaction (RSOI), external electric field, magnetic field, and Aluminium concentration on energy dispersion and conductivity in a Ga1-xAlxAs quantum wire have been explored. The Energy eigenvalues and eigenvectors are quantified using the diagonalization method and the transport properties are computed by Landuer-Bttiker formalism. It is noticed that the external electric field, magnetic field, Rashba spin-orbit interaction, and Aluminium concentration (impurity factor x) alter the energy spectra and conductivity. Hence, these parameters significantly affect the physical and transport properties.
原文链接:- NSTL
- Elsevier
Martinez, Eduardo D.Brites, Carlos D. S.Urbano, Ricardo R.Rettori, Carlos...
10页查看更多>>摘要：We combined the sensing capabilities of Er3+-doped upconverting nanoparticles (UCNPs) with hyperspectral microscopy to construct thermal images on thermally active nanostructures. Here, we studied the heat dissipation of a percolating network of silver nanowires under controlled electric current flow. We quantified the electrothermal action by analyzing the hyperspectral data and constructing 2D maps for the emission intensity, the signal-to-noise ratio, and the thermometric parameter. By studying selected clusters in the network, we concluded that the temperature is quite uniform across the film without any significant thermal gradients. Nonetheless, the thermal evolution was clearly sensed by the UCNPs when the heat dissipation due to the Joule effect was turned on and off, validating the use of this method for studying slow-dynamic thermal processes. Finally, we discuss the accuracy of the thermal readings and the systematic limitations of the proposed method.
原文链接:- NSTL
- Elsevier
Pirot, Bashdar RahmanAbdullah, Nzar RaufManolescu, AndreiGudmundsson, Vidar...
8页查看更多>>摘要：We study thermoelectric transport through a serial double quantum dot (DQD) coupled to two metallic leads with different thermal energies. We take into account the electron sequential and cotunneling effects via different master equation approaches. In the absence of intra- and inter-dot Coulomb interactions, a small peak in thermoelectric and heat currents is found for E-L= E-R indicating the Coulomb blockade DQD regime, where E-L(E-R) is the energy of the state of the left(right) quantum dot. In the presence of intra- and inter-dot Coulomb interactions with strengths U-intra, and U-inter, respectively, avoided crossings or resonance energies between the intra- and the inter-dot two-electron states, 2ES, are found. These resonances induce extra transport channels through the DQD leading to strong side peaks in the thermoelectric and heat currents at E-L- E-R = +/-(U-intra-U-inter) in addition to the main peak generated at E-L=E-R. The current side peaks are enhanced by increased strength of the Coulomb interactions. Interestingly, the current side peaks are enhanced when cotunneling terms are considered in which the resonances of the 2ESs assist the electron cotunneling process through the system. Furthermore, the issue of coherences is carefully checked in the DQD-leads system via different approaches to the master equation, which are the Pauli, the Redfield, a first order Lindblad, and the first- and second order von-Neumann methods. We realize that the Pauli method gives a wrong results for the thermoelectric transport when the role of the coherences is relevant.
原文链接:- NSTL
- Elsevier
