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Using solvent vapor annealing for the enhancement of the stability and efficiency of monolithic hole-conductor-free Perovskite solar cells
In the last few years, perovskite solar cells have attracted enormous interest in the photovoltaic community due to their low cost of materials, tunable band gap, excellent photovoltaic properties and easy process ability at low temperature. In this work, we fabricated hole-conductorfree carbon-based perovskite solar cells with the monolithic structure: glass/FTO/bl-TiO2/(mpTiO2/mp-ZrO2/mp-carbon) perovskite. The mixed 2D/3D perovskite precursor solution composed of PbI2, methylammonium iodide (MAI), and 5-ammoniumvaleric acid iodide (5-AVAI) was dropcasted through triple mesoporous TiO2/ZrO2/carbon electrode films.
8/29/2020 3:46:25 AM +00:00
Transport properties of a GaAs/InGaAs/GaAs quantum well: Temperature, magnetic field and many-body effects
This paper investigate the zero and finite temperature transport properties of a quasi-twodimensional electron gas in a GaAs/InGaAs/GaAs quantum well under a magnetic field, taking into account many-body effects via a local-field correction. We consider the surface roughness, roughness-induced piezoelectric, remote charged impurity and homogenous background charged impurity scattering. The effects of the quantum well width, carrier density, temperature and localfield correction on resistance ratio are investigated. We also consider the dependence of the total mobility on the multiple scattering effect.
8/29/2020 3:46:07 AM +00:00
The mechanism of inverse magnetoresistance in high-ta annealed MnNi/Co/Ag(Cu)/Py spin valves
The magnetic transport properties – magnetoresistive (MR) effects of MnNi/Co/Ag(Cu)/ Py pinned spin valve structures (SVs) prepared by rf sputtering method and annealed at Ta = 100˚C - 500˚C for 30 minutes in high vacuum (∼ 10−5 torr) are investigated. The received results show a change in the observed MR behaviors from a normal GMR effect to an inverse magnetoresistive (IMR) effect after annealing at high temperatures, 300˚C and 400˚C, for these SVs. The origin and mechanism of the IMR behavior are analyzed and discussed. These results will suggest an ability to manufacture SV devices used the IMR effect for enhancing the application capacities for SV-sensor systems.
8/29/2020 3:46:00 AM +00:00
Study of the isomeric ratio of 135m,g 54 m,gXe in photofission 237 93 Np in the giant dipole resonance region
In this work we present the results of measurement of the isomeric ratio of fission fragment 135 54 Xe in photofission of 237Np induced by bremsstrahlung in the Giant Dipole Resonance Region by the method using the inert gaseous flow. The experiments have been performed at the electron accelerator Microtron MT-25 of the Flerov laboratory of Nuclear Reaction, Joint Institute for Nuclear Research, Dubna, Russia. The results were discussed and compared with that of other authors.
8/29/2020 3:45:41 AM +00:00
Size and layer dependence of hybrid graphene/H-BN models upon heating
Different models contained graphene layer are studied via molecular dynamics simulation. Models are heated up from 50K to 8000K via Tersoff and Lennard-Jones potentials to have an entire picture about the evolution of graphene layer in the models upon heating. Various thermodynamic quantities, structural characteristics, and the occurrence of liquidlike atoms are studied, such as, the total energy per atom, the heat capacity per atom, the radial distribution functions, and the appearance of liquid atoms upon heating. The phase transition exhibits the first order. The melting point of graphene layer depends on the number of layers in the models while it does not depend on the size in the range of this study. The melting process of hybrid graphene and hexagonal boron nitride (h-BN) satisfies the first step towards Devil’s staircase type phase transition. The melting point of hybrid graphene/h-BN is close to the one of experiment of graphite.
8/29/2020 3:45:20 AM +00:00
Simulation study of mid-infrared supercontinuum generation at normal dispersion regime in Chalcogenide suspended-core fiber infiltrated with water
This paper report simulation results of supercontinuum generation in the suspended-core optical fibers made of chalcogenide (As2S3) infiltrated with water at mid-infrared wavelength range. Applying water-hole instead of the air-hole in fibers allows improving the dispersion characteristics, hence, contributing to supercontinuum generations.
8/29/2020 3:45:13 AM +00:00
Realization of broadband and independent polarization metamaterial perfect absorber based on the third-order resonance
Since the first observation of the fascinating absorption property, metamaterials have been become a scientific spotlight. A distinctive interest has been given to metamaterial absorber (MA) with a broad operating band, which are more useful for future applications. In this report, we studied numerically and experimentally the electromagnetic properties of perfect MAs using ring-shaped structures at microwave frequencies. By creating a magnetic resonance, the ring structure confines electromagnetic energy at the first- and third-order resonances.
8/29/2020 3:45:00 AM +00:00
Quaternionic reformulation of generalized superluminal electromagnetic fields of dyons
Superluminal electromagnetic fields of dyons are described in T 4- space and Quaternion formulation of various quantum equations is derived. It is shown that on passing from subluminal to superluminal realm via quaternion the theory of dyons becomes the Tachyonic dyons. Corresponding field Equations of Tachyonic dyons are derived in consistent, compact and simpler form.
8/29/2020 3:44:54 AM +00:00
Orbital oscillator commutation relations and mass shifting for superstring
In this work we extend the results obtained in [5] on mass shifting for bosonic string to the case of superstring. The modified anomaly terms of superstring superalgebras are shown and the corresponding BRST charge is used.
8/29/2020 3:44:36 AM +00:00
On generalized Q-deformed fermionic oscillators
In this work we consider a version of generalized q-deformed fermionic oscillators and some their applications. The corresponding coherent states are constructed. The statistical distribution of generalized q-deformed fermionic oscillators system, expressions for quadrature variances and the average particle number in the coherent states are calculated.
8/29/2020 3:44:14 AM +00:00
On a standard model extension with vector-like fermions and abelian symmetry
This paper investigate an extension of the standard model with vector-like fermions and an extra Abelian gauge symmetry. The particle mass spectrum is calculated explicitly. The Lagrangian terms for all the gauge interactions of leptons and quarks in the model are derived. Observe that while there is no new mixing in the lepton sector, the quark mixing plays an important role in the magnitudes of gauge interactions for quarks, particularly the interactions with massive W, Z and Z0 bosons.
8/29/2020 3:44:08 AM +00:00
Numerical analysis of the characteristics of glass photonic crystal fibers infiltrated with alcoholic liquids
The characteristics of photonic crystal fibers (PCFs) with various air hole diameters infiltrated with alcoholic liquids such as ethanol, methanol, propanol and butanol are numerically investigated. Based on the numerical results, we have analyzed and compared in detail the characteristics of these fibers including effective refractive index, effective mode area, dispersion and confinement loss for two sets of parameters {d,Λ} = {1 µm,5 µm} and {1.42 µm, 3.26 µm}, with d the air hole diameter and Λ the lattice constant, respectively. The PCF infiltrated with ethanol and butanol shows better near zero flattened dispersion property at 1.42 µm and 1 µm wavelength, respectively. The values of effective refractive index, effective mode area, dispersion and confinement loss decrease in an orderly manner from butanol, propanol, ethanol to methanol and all the alcoholic liquid’s curves of dispersion are flat and are very close to each other and near the zero dispersion curve. The proposed PCF shows a promising prospect in technology applications such as supercontinuum generation.
8/29/2020 3:44:02 AM +00:00
Neutrinoless double beta decay in the economical 3-3-1 model
Possible contributions to neutrinoless double beta (ββ)0ν decay in the economical 3-3-1 model are discussed. We show that the (ββ)0ν decay in this model is due to both sources— Majorana hMν iL and Dirac hMν iD neutrino masses. If the mixing angle between charged gauge bosons, the standard model W and bilepton Y is in range of the ratio of neutrino masses hMν iL/hMν iD, then both the Majorana and Dirac masses simultaneously give contributions dominant to the decay. As results, constraints on the bilepton mass are also given.
8/29/2020 3:43:56 AM +00:00
Multipartite disentanglement dynamics due simultaneously to amplitude damping and phase damping
In this paper, we shall show that a combined action of both the phase damping and the amplitude damping will force the state’s entanglement to always vanish suddenly in the entire parameter space. Furthermore, we shall prove that by proper local operations such a finite-time disentanglement can be avoided for whatever state’s parameters, no matter the phase damping and the amplitude damping act severally or in combination.
8/29/2020 3:43:50 AM +00:00
Microfluidic chip for trapping magnetic nanoparticiles and heating in terms of biological analysis
In this study, we reported the results of the design and the fabrication a planar coil in copper (square, a = 10 mm, 15µm high, 45 turns), these planar coils were integrated in a microfluidic chip for trapping magnetic nanoparticles and local heating applications.
8/29/2020 3:43:34 AM +00:00
KxNiy[Fe(CN)6].xH2O prussian blue analogue: A study of size effect on the structural, optical and magnetic propertiecs
Recently, striking effects of light irradiation on the magnetic state were reported for Prussian blue (PB) analogues AxCoy[Fe(CN)6] (A = Na, K, Rb, Cs). The physical and optical properties of these compounds are dependent on the size of the particles of the measured samples. However, there have been few reports on the formation of nano-sized particles of the material and the effect of size of the particles on the properties of the compounds. In this report, we present a novel synthesis method of the KxNiy[Fe(CN)6] PB nano-particles and investigate the effect of particle size on the properties of the Prussian blue analog KxNiy[Fe(CN)6] by analyzing the results of the X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-vis absorption and magnetization measurements of the compounds.
8/29/2020 3:43:22 AM +00:00
Influence of sintering temperature on low-field spin-polarized tunneling magnetoresistance of La0.7Ca0.3MnO3
In this study we report the effect of sintering temperature on the low field magnetoresistance (LFMR) of La0,7Ca0,3MnO3 manganite synthesized through sol-gel technique. The La0,7Ca0,3MnO3 has been sintered at 600˚C, 700˚C, 800˚C, 900˚C and 1200˚C. The crystallite as well as particle size also show strong dependence on the sintering temperature. While the ferromagnetic – paramagnetic (FM-PM) transition temperature remains almost constant, the metal – insulation transition temperature drop gradual and the low field magnetoresistance (LFMR) increase with a decrease in grain size.
8/29/2020 3:42:55 AM +00:00
High-order harmonic generation from hydrogen molecular ion in coherent superposition state
In this study, we expand to investigate a more complicated system, H+ 2 molecule in the superposition of the ground and second excited states, exposed to an ultrashort intense laser pulse by numerically solving the time-dependent Schrodinger equation.
8/29/2020 3:42:43 AM +00:00
High temperature symmetry non-restoration and inverse symmetry breaking in the Z2 × Z2 model
The patterns of high temperature symmetry non-restoration (SNR) and inverse symmetry braking (ISB) in the Z2 × Z2 model are investigated in detail for a specified parameters.
8/29/2020 3:42:37 AM +00:00
Full O(α) electroweak radiative corrections to e −e + → W−W+ with initial beam polarization effects
This paper calculate full O(α) electroweak radiative corrections and O(α 3 ) initial state radiation (ISR) corrections to e−e + → W−W+ with initial beam polarization effects. In phenomenological results, we study the impact of electroweak and ISR corrections on cross sections as well as their relevant distributions. We find that the corrections are order of 10% contributions. They are sizable contributions and should be taken into account at future lepton colliders.
8/29/2020 3:42:31 AM +00:00
Facile synthesis of CuO/ITO film via the chronoamperometric electrodeposition for nonenzymatic glucose sensing
The CuO-N/ITO electrode showed the best electrochemical properties for glucose detection in comparison to the others. Chronnoamperometry of CuO-N/ITO electrode to the glucose response showed excellent stability, the linear range of 1 µM to 3600 µM with high sensitivity of 283.6 µAcm−2mM−1 and 0.61 µM of the detection limit (S/N = 3). A good response of the CuO-N/ITO electrode, which was investigated for different human serum samples, indicates a high potential of its towards a glucose sensor for analysis in real examples.
8/29/2020 3:42:18 AM +00:00
Entanglement of a scattered single photon and an exciton
A single photon which is initially uncorrelated with an exciton will evolve to be entangled with the exciton on their continuous kinetic variables in the process of resonant scattering. We find the relations between the entanglement and their physical control parameters, which indicates that high entanglement can be reached by changing specific parameters of exciton.
8/29/2020 3:42:06 AM +00:00
Electrical and optical properties of the hybrid TiO2 nanocrystals – meh-PPV thin films
In this study nanocomposite materials thin films based on poly [2-methoxy-5-(2’-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) and nanocrystalline TiO2 (nc-TiO2) have been fabricated. The photoluminescence (PL) spectra of pure MEH-PPV and nanohybrid films have shown that the excitation at a 377 nm wavelength leads to the strongly enhanced performance in photoluminescent intensity due to the compositions of TiO2 component.
8/29/2020 3:42:00 AM +00:00
Efficient generation of coherent stokes field in hydrogen gas-filled hollow core photonic crystal fibres
This paper study the coherent Stokes generation in a transient stimulated Raman scattering regime by Hydrogen gas-filled hollow-core photonic crystal fibres configuration. The temporal and spatial evolution of the pump and Stokes field envelopes as well as the coherence and population inversion are numerically calculated. The Stokes generation efficiency and the influence of pump pulse width and gas pressure on the energy exchange along fibre are investigated.
8/29/2020 3:41:54 AM +00:00
Effect of spontaneous polarization charges on the electron mobility in ZnO surface quantum wells
This paper theoretical study of the effect due to spontaneous polarization of ZnO on the low-temperature mobility of the two-dimensional electron gas (2DEG) in a ZnO surface quantum well (SFQW). We proved that for the O-polar face this causes an attraction of electrons by the positive charges bound on the surface, while for the Zn-polar face a repulsion of them far away therefrom by the negative bound charges of the same magnitude.
8/29/2020 3:41:36 AM +00:00
Effect of Sm and Mn CO-doping on the crystal structure and magnetic properties of bifeo3 polycrystalline ceramics
The study of microstructure shows no obvious change of grain size and shape. The magnetic properties of the as-prepared samples show the linear magnetic field dependence of magnetization, suggesting the antiferromagnetic feature of polycrystalline ceramics. The field dependence of magnetization measured after two-years synthesis and after applying an electric field reveal a decrease of maximum magnetization but the hysteresis loops retain the antiferromagnetic behavior. The implication of these results is that the magnetic properties of single structural phase compound, including coercivity and remanent magnetization, do not show the aging behavior as observed in the morphotropic phase boundary systems.
8/29/2020 3:41:29 AM +00:00
Effect of annealing temperature on the Li+ ionic conductivity of La0.67−xLi3xTiO3
Perovskite La0.67−xLi3xTiO3 with x = 0.10, 0.11, 0.12 and 0.13 were firstly annealed at 800 oC then treated by reactive milling, followed by post-annealing at temperatures from 1100 to 1200oC. The crystalline structure of grain and grain-boundary were characterized by XRD and SEM. The impedance measurements showed that nanocrystalline La0.67−xLi3xTiO3 after being annealed at 1150 oC possessed a grain conductivity as high as 1.3 × 10−3 S.cm−1 . The grainboundary conductivity was enhanced one order in magnitude after annealing at temperature higher 1100˚C and consists of 5.8 × 10−5 S.cm−1 . The results have also showed the limitation of the adiabatic thermal treatment for the improvement of the grain-boundary conductivity and suggested the way to overcome the limitation by rapidly cooling the samples from the high temperature to room temperature.
8/29/2020 3:41:11 AM +00:00
Detection of luminescence centers in colloidal Cd0.3Zn0.7S nanocrystals by synchronous luminescence spectroscopy
Report the application of synchronous luminescence spectroscopy to detect luminescence centers in colloidal Cd0.3Zn0.7S nanocrystals and the emission peaks at 460 and 515 nm which are attributed to the emission transitions related to sulfur and zinc/cadmium vacancies. The obtained results are useful to clarify the nature of luminescence centers as well as relaxation mechanism in CdxZn1−xS nanocrystals.
8/29/2020 3:40:53 AM +00:00
Decoration of cyclodextrin on surface of porous nanosilica via Disulfide bond for the controlled drug release
The drug releasing behavior of the prepared DOX@PNS-SS-A/CD was also determined using dithiothretol (DTT) which was used to reduce –SS- in PNS-SS-A/CD. Additionally, MTT assay was performed to determine whether the PNS-SS-A/CD may reduce the toxicity to HeLa cells of DOX. The aim of this study is to create an efficiency redoxsensitive PNS for controlled drug delivery.
8/29/2020 3:40:29 AM +00:00
Brst charge operator for generalized deformed SU(2) algebra
The study of quantum groups and algebra [1] - [3] is a direction of actual character in theoretical physics. They find application in many problems such as quantum inverse scattering theory, exactly solvable model in statistical mechanics, rational Conformal field theory, two-demensional field theory with fractional statistics, etc...
8/29/2020 3:40:00 AM +00:00