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The most significant experimental results and theoretical concepts related to chromium dioxide-based composites, according to their influence on the evolution of modern understanding of electron transport phenomena in disordered magnetic systems, are presented. It is shown that the variety of physical processes taking place in powder materials does not allow the development of a holistic theoretical approach to describing the properties of the obtained compacted materials. The properties of composite materials depend on the anisotropy of the shape and magnetic properties of particles of which they are composed. The influence of percolation effects leads to a change in the current-carrying channels morphology with the temperature variation in an external magnetic field. This affects both the shape of the magnetoresistance hysteresis loops and the magnetic field magnitudes corresponding to the magnetoresistance maxima. A wide range of magnetotransport phenomena observed in half-metal composite materials contributes to the development of modern concepts of the conductivity features near the metal-insulator threshold and the influence of the metal-insulator interfaces on tunneling conductivity.

For the first time, studies of the temperature dependences of the thermoelectric power for various compositions of Bi2Sr2CaxZn1−xCu2O8+y (x = 1; 0.8; 0.4) in the range 77–320 K have been carried out. The obtained experimental results are analyzed within the framework of the Xin’s two-band model. The concentration of holes per copper atom and the band gap of the semiconductor type Bi–O layers are determined. It is shown that the replacement of the calcium element with zinc in these proportions does not lead to a change in the electronic band structure of Bi2Sr2CaCu2O8+y.

This work was supported by National Research Foundation of Ukraine, project 2020.02/0217. IK would also like to thank VIAA, State Education Development Agency for Latvian state fellowship. HK would like to thank Ministry of Education and Science of Ukraine, project for young researchers No. 0119U100435. In addition, SP and AAP are thankful for financial support from Latvian Council of Science via grant lzp-2018/2-0083. HK and AAP are grateful for the support from the COST Action CA17126., The paper discusses the results of temperature studies of polymer-based nanocomposites obtained by incorporating multi-walled carbon nanotubes in thin layers of poly(3,4-ethylenedioxythophene):poly(4-styrenesulfonate), specifically focusing on interesting features in the dependencies of electrical properties across the wide range of temperatures from ambient one down to 10 K. --//-- This is the preprint version of the following article: I. Karbovnyk, H. Klym, S. Piskunov, A. A. Popov, D. Chalyy, I. Zhydenko and D. Lukashevych,The impact of temperature on electrical properties of polymer-based nanocomposites, Low Temperature Physics, 46, 1231 (2020), DOI https://doi.org/10.1063/10.0002479, which has been published in final form at https://aip.scitation.org/doi/10.1063/10.0002479., National Research Foundation of Ukraine, project 2020.02/0217; VIAA; Ministry of Education and Science of Ukraine, project for young researchers No. 0119U100435; Latvian Council of Science via grant lzp-2018/2-0083; COST Action CA17126; Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART².

The infrared multiphoton dissociation (IRMPD) spectrum of the protonated heterodimer of ProPheH+, in the range of 2700-3700 cm−1, has been obtained with a Fourier-transform ion cyclotron mass spectrometer combined with an IR OPO laser. The experimental spectrum shows one peak at 3565 cm−1 corresponding to the free carboxyl O-H stretching vibration, and two broad peaks centered at 2935 and 3195 cm−1. Theoretical calculations were performed on the level of M062X/6-311++G(d,p). Results show that the most stable isomer is characterized by a charge-solvated structure in which the proton is bound to the unit of proline. Its predicted spectrum is in good agreement with the experimental one, although the coexistence of salt-bridged structures cannot be entirely excluded.

It is shown that the experimental data on the temperature dependences of the effective electrical resistance and thermal conductivity in the range of 4.2–300 K of the electroconsolidated Fe0.5Ni0.5 composite are within the Hashin–Shtrikman boundaries for the conductivities of a three-phase system. The components of the system are pure Fe and Ni, and the intergranular medium in the form of an alloy with an average composition close to Fe0.5Ni0.5 is considered as the third phase.

The temperature dependences of dynamic magnetic susceptibility of a magnetic superconductor Dy0.6Y0.4Rh3.85Ru0.15B4 in a temperature range of 2–50 К and the field dependence of magnetization up to 6 T at fixed temperatures 2, 11, 18, and 50 K were studied for the first time. It is found that at ТFM = (21 ± 1) К there is a transition to the ferromagnetic state, and at Тc = (6.7 ± 0.1) К a transition to superconducting state is observed, which coexists with the ferromagnetic state in a broad range of temperatures of 2–6.7 K. It is suggested that there exists a triplet mechanism of superconducting coupling in Dy0.6Y0.4Rh3.85Ru0.15B4.The temperature dependences of dynamic magnetic susceptibility of a magnetic superconductor Dy0.6Y0.4Rh3.85Ru0.15B4 in a temperature range of 2–50 К and the field dependence of magnetization up to 6 T at fixed temperatures 2, 11, 18, and 50 K were studied for the first time. It is found that at ТFM = (21 ± 1) К there is a transition to the ferromagnetic state, and at Тc = (6.7 ± 0.1) К a transition to superconducting state is observed, which coexists with the ferromagnetic state in a broad range of temperatures of 2–6.7 K. It is suggested that there exists a triplet mechanism of superconducting coupling in Dy0.6Y0.4Rh3.85Ru0.15B4.

The depletion of a quasi-two-dimensional (quasi-2D) dipolar Bose condensed gas in the presence of both contact and long-range 1/r interactions is investigated in the framework of Hartree–Fock–Bogoliubov (HFB) approximation. When the characteristic wavelength of a mode is much larger than the trap size, the dipole-dipole (DD) interaction can be treated as a contact interaction and in the low momentum limit the long-range nature of the 1/r interaction has the dominant contribution and leads to the nonlinear (nonphononic) dispersion relation. We will show that quantum depletion is temperature independent and is determined by the contact, DD and longrange 1/r coupling constants (ɛdd = gd/g and C). The the quantum depletion is affected by long-range 1/r interaction and at large momentum limits the momentum dependence of quantum depletion unaffected by 1/r interaction.The depletion of a quasi-two-dimensional (quasi-2D) dipolar Bose condensed gas in the presence of both contact and long-range 1/r interactions is investigated in the framework of Hartree–Fock–Bogoliubov (HFB) approximation. When the characteristic wavelength of a mode is much larger than the trap size, the dipole-dipole (DD) interaction can be treated as a contact interaction and in the low momentum limit the long-range nature of the 1/r interaction has the dominant contribution and leads to the nonlinear (nonphononic) dispersion relation. We will show that quantum depletion is temperature independent and is determined by the contact, DD and longrange 1/r coupling constants (ɛdd = gd/g and C). The the quantum depletion is affected by long-range 1/r interaction and at large momentum limits the momentum dependence of quantum depletion unaffected by 1/r interaction.

The exciton spectra of Cs1–xRbxPbCl3 solid solution thin films are studied in a range of 2–6 eV. The formation of solid solutions stable at room temperature was detected in range of concentrations 0 ≤ х ≤ 0.7. A linear dependence of the exciton band and bandgap width parameters on the concentration was found. Kinks are observed along the temperature dependences of the spectral position Em(T) (x > 0) of the long-wave exciton band at 310 and 320 K that are characteristic of second-order phase transitions. The exciton excitations in CsPbCl3 are found to have a three-dimensional nature, while in Cs1–xRbxPbCl3 (x > 0) solid solutions they are found to be two-dimensional.The exciton spectra of Cs1–xRbxPbCl3 solid solution thin films are studied in a range of 2–6 eV. The formation of solid solutions stable at room temperature was detected in range of concentrations 0 ≤ х ≤ 0.7. A linear dependence of the exciton band and bandgap width parameters on the concentration was found. Kinks are observed along the temperature dependences of the spectral position Em(T) (x > 0) of the long-wave exciton band at 310 and 320 K that are characteristic of second-order phase transitions. The exciton excitations in CsPbCl3 are found to have a three-dimensional nature, while in Cs1–xRbxPbCl3 (x > 0) solid solutions they are found to be two-dimensional.

High-resolution absorption spectra of atomic krypton in the range of 11870-12700 cm $^{-1}$ were recorded by employing concentration modulation absorption spectroscopy technique with a tunable single-mode cw Ti:Sapphire laser. The krypton atoms were excited to the absorbing energy states by discharge-burning in a mixture of helium and krypton. A total of 120 lines of neutral krypton were observed, among them 33 lines had already been classified in previous studies, 45 lines were newly classified with the known energy levels, and 42 lines cannot be classified. These unclassified lines indicate that up to now unknown energy levels of Kr must exist. Further, an analysis of the unclassified lines to get possible new energy levels with a classification program is reported.

Droplets and bubbles are thought to be two sides of the same coin; this work determines how true this is at the molecular scale. Stable cylindrical nanodroplets and nanobubbles are obtained in Molecular Dynamics (MD) simulations with three-phase contact lines pinned by alternate hydrophobic and hydrophilic patterns. The surface tension and Tolman length for both types of curved interfaces are obtained with the Kirkwood–Buff method, based on the difference between normal and tangential pressure components. Both bubble and droplet cases are compared to the flat interface case for reference. Results show that the surface tension decreases linearly while the Tolman length increases linearly with the gas/liquid density ratio. By running a careful parameter study of the flat interface over a range of densities, the effect of the density ratio can be corrected isolating the effects of curvature on the surface tension and Tolman length. It is found that such effects start to be seen when the equimolar curvature radius goes down to 20 reduced Lennard–Jones (LJ) units. They have the same magnitude but act with opposite signs for nanodroplet and nanobubble interfaces. Considering effects of the density ratio and curvature, a fitted Tolman equation was obtained, which predicts the surface tension of a curved interface. Results obtained by the fitted Tolman equation agree well with those obtained by the MD simulations except at very small curvature radius (

A new method to determine the arbitrary electron energy distribution function (EEDF) from the optical emission spectroscopic measurement in atmospheric-pressure plasma is introduced. The optical emission spectroscopy (OES) continuum emission spectrum, dominated by electron-neutral bremsstrahlung radiation, is analyzed to inspect the usefulness of the conventional OES measurement range for EEDF determination. The EEDF is reconstructed from the OES continuum radiation spectrum by applying machine learning to solve the bremsstrahlung emissivity equation inversely. Through iterative statistical analysis, the presented genetic algorithm can locate the EEDF reliably. Verification of the algorithm shows that theoretical Maxwellian and Druyvesteynian EEDFs can be partially reconstructed from a realistic OES measurement range. Furthermore, preliminary experimental EEDF results of an argon dielectric barrier discharge (DBD) OES measurement are given. The electron energy range and resolution of the determined EEDF are discussed. The results in this paper show potential for accurate determination of the arbitrary EEDF in atmospheric-pressure plasma using simple OES equipment.

By creating exotic atoms containing an ever-broadening range of particles, researchers can extend the tools of atomic physics to new realms.

The dynamical cluster decay model is applied to understand the decay of 16O+203,205Tl→219,221Ac* reactions by including the deformation effects upto β2i within the hot optimum orientation approach. The evaporation residues of 219,221Ac* nuclei are fitted in the excitation energy range ECN* = 33.1 to 62.4 MeV, by optimizing the only parameter of the model, called neck-length parameter. The DCM calculated cross-sections find nice agreement with the experimental data. The spherical fragmentation of the interacting nuclei is also applied at lowest and highest excitation energies to look for the change in the decay profile while going from the β2i to spherical distribution of fragments. In addition to this, the effect of deformations is also investigated to analyze interaction/ scattering potential.

Low-temperature absorption spectra at temperatures of range of 7.2–300 K in MgF2 and LiF-O,OH crystals were studied to investigate the electron-phonon interaction of radiation-induced color centers in these crystals. The coupling strength (S) with the phonons of the lattice of electronic-vibrational transitions was determined from the ratio of intensities in the zero-phonon line and the integrated absorption band. The nature of the color centers associated eith the absorption band at 390 nm and the emission at 490 nm in LiF-O,OH crystals and for the absorption band at 370 nm and the emission at 420 nm in MgF2 crystals was determined from value of S.

An experimental study on double hydrate dissociation in the presence of air velocity u0 was performed. Forced convection increases the dissociation rate. The experimental curve for the time of the combustion beginning was obtained. During the dissociation of a complex gas hydrate, two typical decay modes can be distinguished. To increase the combustion efficiency of gas hydrate fuel, the most optimal air velocity corresponds to the range of 0.75-1.25 m/s. The increase in the velocity u0 over 3.5 m/s leads to the cessation of fuel combustion.

Using the density functional theory in a local density approximation, Raman spectra of carbon nanoribbons are calcu- lated. It is found that for all the nanoribbons considered by us, there are three active modes: these are the radial breathing mode RBLM in a frequency range of 346-474 cm−1, the localized mode in the frequency range of 1449-1462 cm−1 and the graphene-like mode at the frequency of about 1650 cm−1. These active modes can be useful for identification of the various nanoribbons in Raman scattering experiments.

We have conducted theoretical study on a production reaction 16O(K−,p)K−15C which populates kaonic nuclei CK−15 (=15N-K− bound system). The main purpose of this study is to deduce the kaon-nucleus interaction from the present existing and future experimental observations of kaon-nuclear production through (K−, p) reaction with different targets. Our analysis using 16O target is the first step for our upcoming systematic study by employing wide range of targets. We have considered two models, namely K−pp and Λ*p models in our analysis to determine the formation mechanism of kaonic nucleus and find out the differences between the two models. We have investigated the missing mass spectrum for the above (K−, p) reaction by using Green's function method. The interaction between K− and nucleus is taken to be Woods-Saxon potential. We have analyzed the characteristic of the spectrum by varying the potential strengths as well as scattering angles by using the above two models. It is observed that a large component of quasi free K− is compatible with the Λ*p model.

The paper investigates the effect of Hubbard U (DFT+U) addition on structural and electronic properties of YBa2Cu3O7-δ superconductor. The calculation applies first principles calculation within Generalized Gradient Approximation for Perdew-Burke-Erzenhof for solids (GGA-PBEsol) functional using Density Functional Theory. Energy convergence was found at 400 eV cut-off and 4×4×1 k-point sampling. The DFT+U correction was applied on Cu 3d states at the range of U = 2, 4, 6 and 8 eV where U=2 eV shows the largest band gap difference. Using the GGA-PBEsol+U method, the structural and electronic properties of YBa2Cu3O7-δ were investigated such as its lattice parameters, band structure, the density of states and atomic population.

Many Lattice dynamic models were developed in the past to study the lattice dynamics of metals and their properties. In this present study force constants of Sodium metal have been calculated with the help of De Launay Angular force model. The number of force constants varies with the nature and range of atomic interactions. In the phenomenological theories the force constant of Sodium are evaluated by making use of the experimental data on elastic constants at selected wave vectors. The basic equation of De Launay Angular force model (DAF) relates three elastic constants, force constants as well as two zone boundary frequencies. In the present study, ion-ion interactions of Sodium are considered by neglecting its electron-ion interaction from the proposed relation of DAF model because sodium is the best example of free electron. The force constants of Sodium are calculated here by restricting the range of interaction up to third nearest neighbor. The third angular force constant is considered as neglected because of weaker interaction due to conduction electrons of Sodium. The purpose of this paper is to calculate force constants of Sodium by De Launay Angular Force Model which can be used further in calculation of phonon frequencies of Sodium.

The role of next nearest neighbor (NNN) hopping (t') and next to NNN hopping (t'') on hole pairing and thermodynamic properties such as specific heat, entropy have been investigated using two dimensional (2D) hole-doped t-t'-t''-J model based on exact diagonalization (ED) method. Standard Periodic boundary conditions are applied to minimize error due to finite size effect as the calculations are made using small sized cluster geometry. The attraction between holes increases with the inclusion of third neighbor hopping term. The maximum probability of hole pairing is at NNN site. The system goes to more disordered and ordered state with the increase of long range hopping terms at temperature T≤0.35t and T>0.35t, respectively. A single peak nature is observed in specific heat graph.

Graphene has emerged as a very promising and novel material with exceptional properties such as unique two-dimensional structure, extraordinary electronic, high carrier mobility, thermal conductivity, superior mechanical strength, and ultra-high surface area, and has potential applications in a wide range of technologies. Due to the scarcity of energy resources and the problem of environmental pollution, it is essential to adopt appropriate ways of developing new energy storage materials. Therefore, graphene has been considered as an interesting material for superior-performance electrochemical energy storage such as lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) as it can enhance the capacity, efficiency, gravimetric energy densities, and life cycles of rechargeable batteries. In this chapter, aims to introduce the definition of graphene as a novel support for nanoscale materials that react with lithium (Li)/sodium (Na) and applications in LIBs/SIBs with high capacities.

A technique to produce spin orientation in RI beams was developed for measurements of nuclear moments. The present scheme of two-step reaction realized highly spin-aligned RI beams for a wide range of exotic nuclei. Recently the two-step reaction scheme was applied to the magnetic moment measurement of an isomeric state of a neutron-rich nucleus 75Cu, where its magnetic moment was determined for the first time owing to a 30%-spin-aligned beam. A further perspective of the nuclear moment measurements employing the present scheme is expected.

This paper reveals the structural information of lithium hydride (LiH) at high pressure. The model potential incorporate coulomb interaction potential, short range interaction and van der Waal's attraction energy within the Hafemeister and Flygare approach and the potential term as effective interionic potential model. Values obtained via this technique for LiH, revealed successful phase transition from B1 or NaCl to B2 or CsCl, The estimated transition pressure is 200 GPa, which is quite consistent with the previously available data from different theoretically techniques.

We have studied the photoproduction of Λ(1405) from the CLAS Collaboration with a chiral dynamics model. The reaction γ+p→K+(π∑)0 was conducted for the wide range of photon energies 1.95

We present results of studies of formation mechanism of luminescence centers of the blue range in lithium fluoride crystals. We found that the centers under study are intrinsic defects of crystal lattice formed as a result of a radiation-thermal process in the temperature range much higher than room temperature. Experimental confirmation of simultaneous formation of these centers and F3+ centers, the increase in their concentration during thermal destruction of F3+ centers, and absence of the phonon structure characteristic of R2 centers give basis to attribute the considered centers to a stable configuration of intrinsic radiation defects constituting isomer of F3 center.

Since neutrons especially fast neutron has a high weighting factor in radiation dosimetry, exposing the human’s body to a neutron source in a laboratory or clinic may put body tissues at risk and dangerous situations. In doing so, in this investigation, body tissue together with soft tissues (including adipose and skin) were decomposed into their fundamental elements, and then got emitted by neutrons. This research can be put into operation all tissues about cancer therapy. The amounts of neutron energy because of the collision between neutrons and nuclei of the basic elements got calculated in the tissue Next, some results got concluded. The results imply that the highest transferred energy happens within the energy range 3.5-10.5 MeV and also energy ranges 15-16.5 MeV. As well, the tendencies of the transferred-energy graphs were very in a similar way and are the same as other fundamental elements, and the maximum transferred energy happened for the elements that had a small atomic weight.

We present the analysis of the identified hadrons (π±, K±) produced at mid-rapidity (|η| < 0.5) in collisions of Au-Au ions with energies SNN=4,7,9 and 11 GeV. Particle momentum spectra for charged hadrons (pions, kaons) are measured using data from Monte Carlo generator of Ultrarelativistic Quantum Molecular Dynamics (UrQMD) with particle reconstruction made with the response of Multi-Purpose Detector (MPD) obtained with GEANT3 simulations, on Monte Carlo input. We analyze particle multiplicity dependence on the collision energy. Centrality dependence of transverse momentum spectra was calculated for all particle species. Our goal is to study possible signatures of the phase transition between the hadron state of matter and the quark-gluon plasma (QGP) state.

Hadrontherapy deals with the maximum energy deposition in the form of Bragg peak for energetic charged particles at a particular depth for killing cancerous cells. For planning hadrontherapy treatment accuracy in transport codes are primary demands of radiation oncology. In this work, we studied the dose deposition of the proton beam for the energy range of clinical interest i.e. 70 MeV to 240 MeV in water considering as tissue-equivalent material. The Bragg peak studies for different energy values are executed using Monte Carlo codes-based toolkit- GEANT4. We compared the four physics lists, the QGSP_BERT, the QBBC, the PhysListEmStandardNR (StandardNR), and emstandard_opt0, present in the Geant4 toolkit for avoiding uncertainty in the determination of dose deposition in the living cells which may cause damage of healthy cells. The StandardNR physics list is found suitable to get localized dose deposition in the form of smooth Bragg Curve.

The optical spectra of BaBrI crystals activated by divalent samarium were studied. The samples exhibit bright luminescence in the red region of spectra due to 4f6–4f6 and 4f55d1–4f6 transitions of Sm2+ ions. Luminescence exhibits strong temperature dependence in the range 7–300 K. At low temperatures, luminescence associated with parity-forbidden 4f6–46f transitions from 5D0 and 5D1 states is observed. Coloring of the crystals after irradiation by ultraviolet light and long afterglow luminescence of BaBrI:Sm2+ were detected.

The first synchrotron light source in Thailand was established in 1996, Siam Photon Source is operated and developed the capability of the facility to increase the energy up to 1.2 GeV by Synchrotron Light Research Institute (SLRI). Many users from both inside and outside the country come to use the synchrotron light which is increasing steadily. As a result, Siam Photon Source II at 3 GeV project is taken place in 2019. The Hard X-ray absorption spectroscopy has been planned to support which two consideration designs of the X-ray energy range are 2.4 – 40 keV at the first and 4 – 35 keV at the second. The scattering synchrotron radiation can occur from the optical components in the beamline. The radiation must be controlled to be safe for the utilization of synchrotron radiation in which the radiation shielding design is taken into account. This work aimed to compare the first and second HXAS beamline shielding designs to evaluate the dose distribution to prevent the radiation scattering. The dose calculation was performed by STAC 8 program, therefore, estimate the radiation dose level at the surface outside of the beamline both optic hutch and experimental hutch. The results of the two design indicated that dose distributions with the scattering angle were below the design criteria at 0.1 µSv/h. The optic hutch shielding wall for the first design is below the second design while the experimental hutch shielding wall for the first design is higher than the second design.

Single crystals of PbxSr1-x (NO3)2 mixed system were grown by slow evaporation from solution in the composition range from x=0 to 1.The frequency dependence of dielectric constant and dielectric loss at room temperature is studied in the frequency range 1Hz to 10MHz. The temperature dependence of dielectric constant (e’), dielectric loss (tan δ), A. C. conductivity (σac) and Impedance (Z) is investigated in low temperatures 80 K-300 K, and in different frequency ranges from 1Hz to 10MHz. In view of ever growing applications of these crystals in Stimulated Raman studies, Laser Shifters and optical filters, the results are analysed and discussed.

In this work, we present the experimental results of the study of THz radiation generated by layered WS2, MoSe2 and Mo0.5W0.5S2. THz radiation was observed in the range of 0.1-3 THz. An increase in the amplitude of THz radiation in Mo0.5W0.5S2 relative to WS2, MoSe2 is shown. A symmetry analysis of the azimuthal dependences of THz radiation made it possible to estimate the contribution of THz radiation mechanisms to the generation of THz radiation.

Introduction. Due to the air density correction in the operation of secondary standards with no equivalent air walls, there is a fail of the kPT correction factor in order of 1% to 2.5% in the realization of air kerma rate at the atmospheric conditions of the Mexican highlands (3000 meters above sea level). For this reason, the SSDL-ININ-MEXICO has elected to design and build the Free Air Chamber (FAC), for medium energy X-ray dosimetry. Methods. The air kerma primary standard for X-ray photons is based on parallel-plate FAC for ionometric measurements, which must be operated and designed to fulfill the Charged Particle Equilibrium (CPE) conditions; where the main correction factors is the attenuation factor (katt); therefore, the attenuation length (lat) must be enough to comply with the CPE, where this lat is obtained by Monte Carlo (MC) simulation. Results and discussion. The distribution of the average imparted energy of 300 keV monoenergetic photons as a function of the distance from the reference plane is simulated by the PENELOPE 2008 code, where the plateau corresponds to the CPE region. Therefore, according to the MC simulation, the value of attenuation length lat must be calculated for the point: 44.0 ± 0.5 cm, where the width of the collector electrode is elected 20 cm, within the CPE region of 34 to 54 cm. Conclusions. In this first stage of the design of a FAC, the MC simulation determines that the range to achieve the CPE condition is from 34 to 54 cm, with a collector electrode length of 20 cm and considering an atmospheric pressure P ≈ 710 hPa for a height of 3000 m above sea level.

Within the framework of the Nuclotron–based Ion Collider fAcility (NICA) project an Innovation Block is being constructed. It includes an applied research station for microchips with a package for radiation resistance testing. The ions up to Au with the energy range of 150-350 MeV/n are available for researches. The detailed overview of a technical station for irradiation by long-range ions is presented. A concept for reconstruction of the capsulated microchip structure at it’s interaction with high-energy ions was proposed.

We present plane wave DFT calculations using van der Waals (vdW) functionals on the effects of surface coverage of Pt(111) by adsorbed benzene molecules. In particular, we study the variation of adsorption energy, preferred adsorption site and electronic structure of adsorbed benzene molecule over a range of surface coverage, including experimental saturation coverage value. We find that preferred site for adsorption changes and adsorption energy generally reduces as the surface coverage of benzene increases. Benzene molecules would preferably chemisorb until saturation coverage is attained and further form physisorbed layers on Pt(111) surface, similar to the results reported on Ni(111) and Ru(001). Benzene attains a tilted configuration with respect to the Pt(111) surface at higher coverage, in agreement with earlier experimental and theoretical data.

To study the dependence of incomplete fusion on entrance channel parameters, the excitation functions of evaporation residues populated through complete and/or incomplete fusion in 19F + 154Sm system were measured at projectile energy range ≈ 4–6 MeV/nucleon The measured excitation functions were compared with theoretical model PACE-4 predictions. Analysis of measured data suggests the production of xn/pxn-channels via complete fusion, as these were satisfactorily reproduced by PACE-4 cross-sections, while, a significant enhancement in the cross-sections of α-emitting channels was found, which was attributed due to the incomplete fusion process. A systematic study suggests that the incomplete fusion contribution increases with the entrance channel mass asymmetry and coulomb factor. Further, a study on the breakup threshold suggests that the incomplete fusion contribution increases with decrease in the α-Q value of the projectile. These present results clearly show the effect of projectile structure on ICF dynamics along with other entrance channel parameters.

The process of hemolysis of erythrocyte suspension induced by hydrochloric acid (HCl) is investigated by measuring the UV-Vis absorption spectrum in the range 250 nm - 750 nm at interval 1 nm. The spectrum is measured each 15 s which permitted to follow the changes in absorbance at different wavelengths during hemolysis. The kinetics of the hemolysis is monitored by the changes in the absorbance at 700 nm, and by the changes in the wavelength of the main absorbance peak in the spectrum due to the hemoglobin. Because of the finite number and discrete values of the wavelengths used in the measurement the real value of the peak wavelengths in the spectra must be found by additional processing of the experimental data. The procedure uses the first derivative of the spectrum (dA/dt) and a geometrical approach to calculate the value of the wavelength at which the first derivative dA/dt is equal to 0. The procedure smoothed the kinetic curve of the peak wavelength to a great extent. This permit to compare it to the curve of the absorbance at 700 nm and to make assumptions of the process that occurs during the acid hemolysis. The procedure could be applied to any process where there is a shift in the peaks’ wavelength.

In the present study, we report on dispersion function over a spectral range of 300-1700 nm (i.e. 0.73-4.13eV) for CVD-grown full area coverage monolayer WS2 and WSe2 films on SiO2/Si substrates. The result is obtained via the analysis of spectroscopic ellipsometry spectra by virtue of Tauc-Lorentz oscillators, which takes into account that absorption of these materials are attributed to the formation of the excitons.

In this paper, the double-Λ hypernuclei, HΛΛ6e, HΛΛ5e and HΛΛ5e have been theoretically investigated to determine effective Λ-Λ interaction energies in double-Λ hypernuclei which is closely related to hyperon superfluidity in neutron stars. These double-Λ hypernuclei were considered as three-body cluster model; Λ-Λ-core nucleus. We constructed the free-space single-channel Λ-Λ interaction from Shinmura's multi-channel S=-2 potentials which are phase shift equivalent to Nijmegen soft core potentials. The interaction strength and range parameter are fitted with the most updated experimental data of Nagara event from E373 experiment. By using NSC97e potential, the effective Λ-Λ interaction energies are found to be 0.67 MeV, 0.88 MeV and 0.64 MeV for HΛΛ6e, HΛΛ5e and HΛΛ5e respectively. The medium effects are not negligible in these double-Λ hypernuclei.

Exciton absorption spectra of thin films of complex compounds AgPbBr3, AgPb2Br5, and AgPb3Br7 were studied in the photon energy range 2–6 eV. It was established that the compounds belong to the direct band dielectrics; low-frequency excitons are localized in the structural layers (PbBr8)6– of the crystal lattice and have a quasi-two-dimensional nature.

The self-assembly of binary colloidal mixtures provides a bottom-up approach to create novel functional materials. To elucidate the effect of composition, temperature and pressure on the self-assembly behavior of size-asymmetric mixtures, we performed extensive dynamics simulations of a simple model of polymer-grafted colloids. We have used a core-softened interaction potential and extended it to represent attractive interactions between unlike colloids and repulsion between like colloids. Our study focused on size-asymmetric mixtures, where the ratio between the sizes of the colloidal cores was fixed at $\frac{\sigma_{B}}{\sigma_{A}}=0.5$. We have performed extensive simulations in the NPT and NVT ensembles to elucidate the phase behavior and dynamics of mixtures with different stoichiometric ratios. Our simulation results uncovered a rich phase behavior, including the formation of hierarchical structures with many potential applications. For compositions where the small colloids are the majority, sublattice melting occurs for a wide range of densities. As the temperature is decreased, the small colloids localize, akin to a metal-insulator transition, with the small colloids playing a role similar to electrons. Under these conditions the large colloids form a well-defined lattice, whereas small colloids can diffuse through the system. Our results are summarized in terms of phase diagrams.

We have employed a variable stripe length method in order to measure the optical gain of GaAs/AlGaAs quantum rings. Although the large lateral diameter of quantum rings ( ∼ 50 nm) with a few nm size distribution is expected to cause a small spectral inhomogeneity ( ∼ 1 %), a broad gain width ( ∼ 300 meV) was observed. This result was attributed to a variation of the vertical heights and variations in localized states that exhibit crescent shaped wavefunctions, whereby the energy levels are distributed over a broad spectral range. When the excitation intensity is decreased, irregular peaks appear in the gain spectrum gradually. Similar phenomena were also observed as the temperature increased. We conclude that excited carriers in quantum rings are distributed stochastically at various localized states and that the population inversion is sensitive to both excitation intensity and temperature.

Mass transport of the Knudsen gas in a porous medium is investigated on the basis of the kinetic theory of gases. First, the mass flow conductance is computed numerically for various porosities and solid grain sizes by stochastic particle simulations (SPS). Then, a kinetic model with a homogeneous scatterer is introduced, which contains the reference Knudsen number as the sole parameter that characterizes the collision frequency of gas molecules with the micro-structural solid surface. With the aid of the standard asymptotic analyses for small and large Knudsen numbers combined with the percolation theory, the effective reference Knudsen number is identified to reproduce the SPS results for a wide range of porosities., This paper is part of the Special Topic, Advances in Micro/Nano Fluid Flows: In Memory of Prof. Jason Reese.

The AC magnetic susceptibility (ACS) of Fe3O4 nanoparticles was measured between 10 kHz and 4 MHz at different temperatures and in applied DC fields. In this frequency range, magnetostatic interactions impact magnetization dynamics even for dilute assemblies. The ACS spectrum of relaxation frequencies changes both with temperature and the addition of a small DC field. Because both the relaxation peak frequency and amplitude can be tuned with the DC field, these results could be applied to magnetic hyperthermia applications to optimize heat delivery.

The stability of liquid films on surfaces are critically important in microscale patterning and the semiconductor industry. If the film is sufficiently thin it may spontaneously dewet from the surface. The timescale and rate of dewetting depend on the film repellency of the surface and the properties of the liquid. Therefore, control over the repellency requires modifying surface chemistry and liquid properties to obtain the desired rate of film retraction. Here, we report how the dynamics of a receding thin liquid stripe to a spherical cap droplet can be controlled by programming surface repellency through a non-contact electrostatic method. We observe excellent agreement between the expected scaling of the dynamics for a wide range of voltage-selected final contact angles. Our results provide a method of controlling the dynamics of dewetting with high precision and locality relevant to printing and directed templating.

Cadmium zinc telluride (CZT) is an ideal material for room temperature nuclear radiation detection, but CZT crystals of high quality and low defects concentration are difficult to obtain. Therefore, in order to improve the performance of the CZT detector, the working conditions of the CZT detector could be appropriately changed to make the internal electric field of the CZT detector close to uniform distribution so as to improve the electron transport performance. In this paper, alpha induced transient charge analysis has been used to study the internal electric field of the CZT detector, and deep level defects in CZT were linked with internal electric field distribution. Based on the process, a variety of deep level defects on electron trapping and detrapping by changing the temperature, the output waveform change of charge sensitive preamplifier (the pulse height spectra for alpha radiation at different temperatures) was observed, and then the effects of deep level defects on electron mobility ( μe), electron transport time ( TR), the internal electric field, and the electron collection efficiency of the CZT detector were analyzed. The experimental results indicated that the influence of deep level defects was a main factor to the internal electric field in the range of −140 to 40 °C. As the temperature rises, the influence of these defects weakens, μe and electron collection efficiency both increase, and internal electric field distribution tends to be uniform. Moreover, with the further increasing temperature (−40 to 20 °C), μe decreased and internal electric field distribution became fluctuating, but electron collection efficiency was basically unchanged, which suggested that the influence of lattice vibration in the range of −40 to 20 °C turned to be the main factor. The above conclusions demonstrated that although the CZT detector has excellent room temperature detection ability, room temperature was not its optimal working temperature due to the influence of high concentration deep level defects. At −20 °C, the CZT detector presented the highest electron collection efficiency and maximum which limited the influence of deep level defects on electron transport, performing the optimal properties.

Ge doping in AlGaN was studied over a wide dopant concentration range. For high Ge concentrations, the formation of VIII–nGeIII was determined to be the main point defect limiting the conductivity. It was shown that the complex formation could be suppressed by controlling chemical potentials during growth, leading to a higher maximum achievable carrier concentration and selective stabilization of a certain complex type. Chemical potential of the growth species was varied by changing the V/III ratio and growth temperature. Free carrier concentrations as high as 4 × 1019 cm−3 were achieved in Al0.4Ga0.6N:Ge grown on sapphire substrates under “metal-rich” conditions. The ability to control the onset of self-compensation and to stabilize a certain charge state of the compensating defect is of great technological importance for application of AlGaN in various devices.

The crystal structure of tungsten monocarbide (WC) is researched from 0 to 650 GPa through first principles calculations. The results verify that the experimental structure (hP2-WC) with the space group P 6¯m2 is the most stable phase in a wide range of pressure. Above 231 GPa, a new stable structure (space group P63/mmc, hP4-WC) is found to be the most stable phase, and it will transform to a CsCl-type phase (cF8-WC) around 582 GPa. Phonon calculations reveal that the hP4-WC phase is dynamically stable and may be a metastable structure at ambient conditions. The cF8-WC phase possesses dynamical stability above 20 GPa. The hP4-WC phase is a low compressible material with a large bulk modulus of 377 GPa at zero pressure. The hardness values of hP2-WC and hP4-WC at zero pressure are 32 and 21 GPa, respectively, while the cF8-WC phase possesses a hardness of 21 GPa at 20 GPa, implying that these phases are potential hard materials. The temperature–pressure phase boundary of WC is obtained by means of the quasi-harmonic approximation method. As the temperature increases, the transition pressure from hP2-WC to hP4-WC remained nearly unchanged. The transition pressure between hP4-WC and cF8-WC decreases with the increasing temperature.

We report on the results of an experimental campaign to measure time-varying velocity distributions in the near-field of a low power Hall thruster. We employ a sample-hold technique, enhanced by parallelizing the measurement hardware into several signal processing channels that vastly increases the data acquisition rate. The measurements are applied to study flow field dynamics in a commercial BHT-600 Hall thruster undergoing unforced breathing mode oscillations in the 44–49 kHz range. A very detailed experimental picture of the near-field emerges from these studies. The results indicate that velocity fluctuations lessen further downstream of the exit plane. Along the thruster axis where there is a general appearance of a central jet, there is evidence of a low velocity ion population in between the periodic bursts of high velocity ions, indicative of local ionization of neutrals outside of the thruster. One possible source of this residual ionization may be background chamber gas, which is not unexpected with the limited pumping capacity of ground test facilities.

A simple model describing the most significant impact of electromagnetic heating on pathogen-containing aerosols is presented. While the physics of ohmic heating are well understood, the connection between the unsteady temperature increase with net pathogen inactivation in an aerosolized electrolyte solution over a range of frequencies is not clear. The model is composed of two parts: a thermal model of electromagnetic heating of the droplets and a survival model describing the active pathogen population as a function of time. The droplets of saline solution, whose electrical conductivity depends on salt concentration and carrier frequency, are assumed to be small enough so that ambient air flows are sufficient to counter gravity, and the droplets are assumed to be equally spaced. As the droplets move with the ambient air, energy transport is limited to conduction, and within an adiabatic system, the mean spatial mode dominates the thermal transients of the air-droplet system. The kill rate of the pathogen depends on temperature, and the result of our thermal model informs the pathogen population through the Arrhenius kill rate. The model shows strong qualitative agreement with microwave inactivation of MS2 bacteriophages in aerosolized droplets. Inactivation is improved with larger electric field amplitudes, even for small duty cycles. We show that for a range of viruses with known activation energy, the thermal inactivation mechanism is more reliable for viruses with larger activation energy.