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In this study, the dynamic characteristics of water droplets impinging on a heated cylinder were investigated using a high-speed camera regarding the diameter ratios between droplet and cylinder. Water droplets generated by a needle in the range of 2.5 mm to 5.0 mm in diameter were impinged onto a cartridge heater with surface temperature of 25 °C and 300 °C. The diameter of the cartridge heater was 6.0 mm. The recording rate of the high-speed camera was set to 10,000 Hz, and the Weber number was controlled from 17.4 to 217 by adjusting the free-fall height of the water droplets. As a result, the dynamic characteristics of water droplets impinging on cylinder were different depending on the diameter ratio and Weber number. In the high-temperature region, the water droplets were detached from the cylinder after the impingement by Leidenfrost effect. Under conditions of low Weber number and low diameter ratio, the water droplets were rebounded in the opposite direction of the impingement, maintaining its shape. However, as the Weber number increases, the water droplets impinging on cylinder were broken-up and detached by the Leidenfrost effect regardless of the diameter ratio. This study is expected to be utilized to determine the dynamic characteristics of droplet, and be applied such as phenomenon analysis of the heat transfer and cooling.

The growing evidence of increased magnetite nanoparticles (both endo- and exo-genic) in the human brain raises the importance of assessing the entire power deposition when electromagnetic waves at GHz frequencies propagate in such tissues. This frequency range corresponds to many popular portable communication devices that emit radiation close to a human's head. At these frequencies, the current dosimetric numerical codes can not accurately compute the magnetic losses part. This is due to the lack of an implemented computational algorithm based on solving the coupled Maxwell and Landau-Lifshitz-Gilbert equations, in the case of magneto-dielectrics, considering eddy currents losses and specific properties of magnetic sub-millimetric particles. This paper focuses on analyzing the limits and the inconsistencies when using commercial dosimetric numerical software to analyze the total absorbed power in brain models having ferrimagnetic content and being exposed to 3.5GHz electromagnetic waves. Magnetic losses computed using Polder’s permeability tensor as constitutive relation lead to unreliable results. However, using such software can provide a preliminary view of the electromagnetic impact of ultra- and super-high frequencies on magnetic-dielectric tissues.

The gamma-ray emission of RX J1713–3946, despite being extensively studied in the GeV and TeV domains, remains poorly understood. This is mostly because, in this range, two competing mechanisms can efficiently produce gamma-rays: the inverse Compton scattering of accelerated electrons, and interactions of accelerated protons with the nuclei of the interstellar medium (ISM). In addition to the acceleration of particles from the thermal pool, the re-acceleration of pre-existing cosmic rays is often overlooked, and has in fact also been taken into account. Especially, because of the distance to the SNR (∼1 kpc), and the low density in which the shock is currently expanding (∼10−2 cm−3), the re-acceleration of cosmic-ray electrons pre-existing in the ISM can account for a significant fraction of the observed gamma-ray emission, and contribute to the shaping of the spectrum in the GeV–TeV range. Remarkably, this emission of leptonic origin is found to be close to the level of the gamma-ray signal in the TeV range, provided that the spectrum of pre-exisiting cosmic-ray electrons is similar to that observed in the local ISM. The overall gamma-ray spectrum of RX J1713–3946 is naturally produced as the sum of leptonic emission from re-accelerated cosmic-ray electrons, and a subdominant hadronic emission from accelerated protons. We also argue that neutrino observations with next-generation detectors might lead to a detection even in the case of a lepto–hadronic origin of the gamma-ray emission.

In the current study, 10PbO-xSrO-(90-x)B2O3 (x is between 20 and 45 mol% with a step of 5 mol%) glasses with SrO inserted in various proportions were surveyed in terms of nuclear shielding qualities. Gamma- ray shielding features of the glasses encoded BPS1-BPS6 were investigated in the energy range of 0.015–15 MeV. The mass attenuation coefficients (MAC) of BPS glasses were composed via GEANT4 simulation codes and the accuracy of the outcomes was checked by WinXCOM software. The MAC values of BPS1 and BPS6 glasses were obtained between 14.934–0.024 g/cm2 and 19.047–0.029 g/cm2 in the energy range of 0.015–15 MeV. Further, other essential parameters, MFP, Zeff, Zeq, EABF, and EBF were derived from the MAC values for the same energies. It was noted that the MFP values of the BPS6 glass are higher than some commercial glasses and ordinary concrete at chosen energy intervals. According to the results achieved, EBF, EABF, and MFP values decline as the percentage of SrO in the BPS glasses increases. The highest Zeff was achieved by BPS6 (with 45% SrO), while the lowest Zeff was obtained by BPS1 (with 20% SrO). Finally, fast neutron removal cross-sections (ΣR), Mass Stopping Power (MSP), and Projected Range (PR) values were computed to investigate the fast neutron, proton and alpha shielding properties of SrO added BPS glasses. It is seen that the ΣR values of BPS glasses vary in the range of 0.126 cm−1–0.117 cm−1. The addition of SrO in the glass leads to reduce the ranges of charged and uncharged particles. According to the outcomes achieved, BPS6 glass with 45% SrO additives can be regarded as an effective radiation shield used in many technological disciplines.

Upon treatment with Cs2CO3, S-methyl-N-ynonylsulfoximines undergo 5-exo-dig cyclizations to give three-dimensional heterocycles. The reactions proceed at ambient temperature with a wide range of substrates affording the corresponding products in good to excellent yields.

The scope of this work was to investigate the quench sensitivity of a high-purity wrought aluminum alloy Al6Zn0.75 Mg (in this work called 7003pure). This is compared to a similar alloy with the additions of Fe, Si, and Zr at a sum less than 0.3 at.% (in this work called 7003Fe,Si,Zr). Differential scanning calorimetry (DSC) was used for an in situ analysis of quench induced precipitation in a wide range of cooling rates varying between 0.0003 and 3 K/s. In 7003pure, three main precipitation reactions were observed during cooling, a medium temperature reaction with a distinct double peak between 325 and 175 °C and a very low temperature reaction starting at about 100 °C. An additional high temperature reaction related to the precipitation of Mg2Si starting at 425 °C has been observed for 7003Fe,Si,Zr. In terms of hardness after natural as well as artificial aging, alloy 7003pure shows a very low quench sensitivity. Hardness values on the saturation level of about 120 HV1 are seen down to cooling rates of 0.003 K/s. The as-quenched hardness (5 min of natural aging) shows a maximum at a cooling rate of 0.003 K/s, while slower and faster cooling results in a lower hardness. In terms of hardness after aging, 0.003 K/s could be defined as the technological critical cooling rate, which is much higher for 7003Fe,Si,Zr (0.3–1 K/s). The physical critical cooling rates for the suppression of any precipitation during cooling were found to be about 10 K/s for both variants.

is a neutrino–nucleus interaction simulation program library. It can be used to simulate interactions for neutrinos with between 100 MeV and a few TeV of energy. is also capable of simulating hadron interactions within a nucleus and is used to model nucleon decay and hadron–nucleus interactions for particle propagation in detector simulations. This article describes the range of interactions modelled and how each is implemented.

Crystallization of lysozyme is investigated upon rapid cooling to 4°C of undersaturated solutions equilibrated at temperatures in the range 30°C–44°C, and for incubation times varying from 12 to 36...

The present study proposes to examine the effect of dietary levels of metabolizable energy, under a fixed nutrient:calorie ratio, on the production performance; body fat and protein deposition; and carcass characteristics of free-range broilers from 1 to 84 days of age. Nine hundred unsexed chicks were allocated to six treatments in a completely randomized design with six replicates of 25 birds each. Treatments consisted of diets with varying levels of metabolizable energy (2700, 2800, 2900, 3000, 3100 and 3200 Kcal ME/kg of diet) and a fixed proportion of nutrients relative to the energy level according to the nutritional requirements for each rearing phase. Body weight, weight gain, feed intake, feed conversion, production viability, metabolizable energy intake, protein intake, lysine intake, body fat deposition, body protein deposition and carcass characteristics were evaluated. Data were subjected to analysis of variance and, later, to regression analysis. Increasing levels of metabolizable energy, coupled with a fixed nutrient:calorie ratio, reduced feed intake, increased body weight and weight gain, improved feed conversion and did not affect carcass characteristics. In conclusion, adjusting the nutrient supply according to the dietary energy level improves production performance by improving feed conversion, ensuring adequate nutrient intake and preserving fat and protein deposition in the carcass when the metabolizable energy level is raised up to 3200 Kcal/kg in all rearing stages. O objetivo do presente estudo foi avaliar os níveis de energia metabolizável, sob uma relação nutriente:caloria fixa, no desempenho produtivo; deposição de gordura e proteína corporal e características de carcaça de frangos de corte tipo caipiras. Foram utilizados novecentos pintainhos não sexados, distribuidos em seis tratamentos em delineamento inteiramente casualizado com seis repetições de 25 aves cada. Os tratamentos consistiram em dietas com diferentes níveis de energia metabolizável (2700, 2800, 2900, 3000, 3100 e 3200 Kcal EM / kg de dieta) e uma proporção fixa de nutrientes em relação ao nível de energia de acordo com as necessidades nutricionais de cada fase de criação. Foram avaliados o peso corporal, ganho de peso, consumo de ração, conversão alimentar, viabilidade criatória, consumo de energia metabolizável, consumo de proteína, consumo de lisina, deposição de gordura corporal, deposição de proteína corporal e características de carcaça. Os dados foram submetidos à análise de variância e posteriormente à análise de regressão. O aumento dos níveis de energia metabolizável juntamente com a manutenção da relação nutriente:caloria reduziu o consumo de ração, aumentou o peso corporal e o ganho de peso, melhorou a conversão alimentar e não afetou as características da carcaça. Em conclusão, o ajuste da oferta de nutrientes de acordo com o nível de energia da dieta melhora o desempenho da produção, melhorando a conversão alimentar, garantindo a ingestão adequada de nutrientes e preservando a deposição de gordura e proteína na carcaça quando o nível de energia metabolizável é elevado até 3200 Kcal/kg em todas as fases de criação.

Due to the high theoretical specific capacity and low cost, FeF3·0.33H2O has become one of the potential choices of cathode materials for sodium-ion batteries. However, the poor intrinsic conductivity limits its practical applications. Herein, the atomic substitution is used to improve its intrinsic conductivity. The first-principles calculation results show that Cr3+ doping can reduce the band gap of FeF3·0.33H2O to improve its intrinsic conductivity. The discharge specific capacity of Fe0.95Cr0.05F3·0.33H2O with a narrowest band gap is 194.02 mA h/g at 0.1 C within the range of 1.4-4.0 V, which is higher than that of FeF3·0.33H2O (136.47 mA h/g). Using the electrochemical impedance spectroscopy and galvanostatic intermittent titration technique tests, it is found that Rct of Fe0.95Cr0.05F3·0.33H2O is reduced and DNa+ is almost unchanged, as compared to FeF3·0.33H2O.

Understanding and broad screening Li interaction energetics with surfaces are key to the development of materials for a wide range of applications including Li-based electrochemical capacitors, Li sensors, Li separation membranes, and Li-ion batteries. In this work, we build a high-throughput screening scheme to screen Li adsorption energetics on 2D metallic materials. First, density functional theory and graph convolution networks are utilized to calculate the minimum Li adsorption energies for some 2D metallic materials. The data is then used to find a dependence of the minimum Li adsorption energies on the sum of ionization potential, work function of the 2D metal, and coupling energy between Li+ and substrate, and the dependence is used to screen all 2D metallic materials. Physics-simplified learning by splitting the property into different contributions and learning or calculating each component is shown to have higher accuracy and transferability for machine learning of complex materials properties.

In this work, radical anion photodetachment photoelectron (PD-PE) spectra of N-methylacridone (NM-AC) and N,N'-dimethyl-trans-quinacridone (NNM-QAC) are presented, from which we derived electron affinities and transition energies from S0 to the lowest excited triplet and singlet states (T1, T2, and S1). Because in molecules with extended π systems and heteroatoms the state density even in the energy range of the lowest excited electronic states is already high, assignment of most of the spectral structures in the PD-PE spectra was possible only on the basis of theoretical calculations. To this end, adiabatic transition energies including zero-point vibrational energy corrections were determined using a combination of density functional theory, time-dependent density functional theory, and multireference configuration interaction methods. Calculated Franck-Condon spectra proved to be particularly valuable for the assignment of the spectra. Surprisingly, the density of electronically excited states in the low-energy regime is smaller for NNM-QAC than for NM-AC. This is due to the fact that the nπ* energies remain nearly the same in the two molecules whereas the lowest ππ* excited singlet and triplet transitions are strongly red-shifted in going from NM-AC to NNM-QAC.

The coalescence behavior of two droplets with different viscosities in the funnel-typed expansion chamber in T-junction microchannel was investigated experimentally and compared with droplet coalescence of the same viscosity. Four types of coalescence regimes were observed: contact non-coalescence, squeeze non-coalescence, two-droplet coalescence and pinch-off coalescence. For droplet coalescence of different viscosities, the operating range of non-coalescence becomes narrowed compared to the droplet coalescence of same viscosity, and it shrinks with increasing viscosity ratio η of two droplets, indicating that the difference in the viscosity of two droplets is conducive to coalescence, especially when 1＜η＜6. Furthermore, the influences of viscosity ratio and droplet size on the film drainage time (Tdr) and critical capillary number (Cac) were studied systematically. It was found that the film drainage time declined with the increase of average droplet size, which abided by power-law relation with the size difference and viscosity ratio of the two droplets: Tdr ~ (ld)0.25±0.04 and Tdr ~ (η)−0.1±0.02. For droplet coalescence of same viscosity, the relation of critical capillary number with two-phase viscosity ratio and dimensionless droplet size is Cac = 0.48λ0.26l−2.64, while for droplet coalescence of different viscosities, the scaling of critical capillary number with dimensionless average droplet size, dimensionless droplet size difference and viscosity ratio of two droplets is Cac = 0.11η−0.07ls−2.23ld0.16.

In this letter, we perform a first-principles study on the adsorption performance of the InP3 monolayer upon three SF6 decomposed species, including SO2, SOF2, and SO2F2, to investigate its potential as a resistance-type, optical or field-effect transistor gas sensor. Results indicate that the InP3 monolayer exhibits strong chemisorption upon SO2 but weak physisorption upon SO2F2. The most admirable adsorption behavior is upon SOF2, which provides a favorable sensing response (-19.4%) and recovery property (10.4 s) at room temperature as a resistance-type gas sensor. A high response of 180.7% upon SO2 and a poor one of -1.9% upon SO2F2 are also identified, which reveals the feasibility of the InP3 monolayer as a resistance-type sensor for SO2 detection with recycle use via a heating technique to clean the surface. Moreover, the InP3 monolayer is a promising optical sensor for SO2 detection due to the obvious changes in adsorption peaks within the range of ultraviolet and is a desirable field-effect transistor sensor for selective and sensitive detection of SO2 and SOF2 given the evident changes of QT and Eg under the applied electric field.

This work is aimed at investigating the effects of the refrigerant charge, expansion device restriction, compressor speed, and their interactions on the performance of a household refrigerator. To this end, a micrometric valve was installed in series with the capillary tube of a frost-free refrigerator to vary the expansion restriction within a range equivalent to capillary tubes with inner diameters spanning from 0.55 to 0.85 mm. The refrigerant charge was manually changed from 35 to 65 g whereas the compressor speed was adjusted between 2500 and 4500 rpm. In total, 294 steady-state energy consumption tests were conducted, being 147 at a surrounding temperature of 32 °C, and the rest at 16 °C. It was noticed that low energy consumptions can be achieved for several combination of refrigerant charge and expansion restriction, albeit the minimal energy consumption figures were always achieved for the highest charges and restrictions. It was also verified that the refrigerator operates in a sub-optimum region so that increasing the charge from 42 g to 52 g while decreasing the capillary tube diameter from 0.64 mm to 0.60 mm led to a 3% decrease on the energy consumption. It was also found that a single combination of refrigerant charge and equivalent diameter provided satisfactory performance levels regardless of the compressor speed. Finally, a method to reduce the number of tests was proposed, in such a way that only 9 datapoints are required to generate a full energy consumption map for a given compressor speed and surrounding temperature.

Three groups of charged particles are recorded at the impact of the laser radiation pulse with a metal target in a rarefied gas medium. The optical range laser radiation intensity is ~109 W/cm2. A possibility of using a Langmuir probe for diagnosing plasma processes with nanosecond resolution is demonstrated.

An optical model analysis of the elastic scattering of protons on 6Li nuclei for proton energies Ep of 50 keV to 185 MeV is performed using the new OptModel program developed by L.N. Generalov and V.A. Zherebtsov for n, p, d, t, 3,4,6He, 6Li projectiles with allowance for the resonance part of elastic scattering. All accessible data on differential and total cross sections and polarization are analyzed simultaneously. Violation of scattering matrix unitarity (optical model + resonance) at several energy values is less than 10%, which corresponds to the mean errors of the data analyzed. The running of the code at the astrophysical interaction energy range is of great interest for actual nuclear vertex constants research.

Charge transport in amorphous silicon nitride (Si3N4) is studied experimentally in a wide range of electric fields and temperatures. The experimental data are compared with the results of numerical calculations. To describe the ionization of deep centers (traps) in Si3N4, the Frenkel effect is used with the account for thermally assisted tunneling and the multiphonon mechanism. It is shown that the Frenkel effect with allowance for thermally assisted tunneling formally describes the experiment. However, an anomalously small frequency factor (109 s–1) and a large effective tunneling mass (3m0) must be used in calculations in this case. A satisfactory agreement between the results of experiments and calculations was attained using the theory of multiphonon ionization of traps with the following parameters: $$W_{T}^{{e,h}}$$ = 1.6 eV, $$W_{{{\text{opt}}}}^{{e,h}}$$ = 3.2 eV, $$W_{{{\text{ph}}}}^{{e,h}}$$ = 0.064 eV, $$m_{{e,h}}^{*}$$ = 0.6m0, and Ne,h = 6 × 1018 cm–3, which correspond to the thermal energy, optical energy, phonon energy, tunneling effective mass, and concentrations of electron and hole traps, respectively.

The present study aims to assess the proton conductivities of the most investigated proton exchange membranes (PEMs) used in PEM fuel cells (PEMFCs). Specifically, PEMs are analyzed for their use in anhydrous fuel cells and proton conductivity upper bounds were provided for them. Considering the direct relationship between proton conductivity and temperature, an upper bound is presented. Based on the obtained upper bounds, suitable membranes for high-temperature performance are determined, and the average range of proton conductivity for each polymer group is discussed. By comparing the available proton conductivity data with upper bound, it was demonstrated that some of poly (ionic liquid)s have provided the highest proton conductivities, however aromatic polymers such as polybenzimidazole (PBI) are found more suitable choices for application at anhydrous conditions and high temperatures. The proton conductivity upper bound for anhydrous PEMs demonstrates the availability of promising polymer options for the deployment of anhydrous fuel cells.

Plasma 4(4), 670 - 680 (2021). doi:10.3390/plasma4040034, Published by MDPI, Basel

Temperature sensing from the photoluminescence of MgAl2O4:Cr3+ ceramic powder is systematically investigated. Material was prepared by self-propagating high temperature synthesis method. In this host, Cr3+ experiences the strong crystal field, so the overlapping emissions from 2E and 4T2 energy levels are observed. Emission and excitation spectra were recorded from 300 K to 540 K. The broad photoluminescence attributed to 4T2→4A2 emission gains in intensity with increase in temperature on account of 2E→4A2 emission intensity until 460 K when both emissions start quenching. The emissions were separated by deconvolution at each temperature and used for the luminescence intensity ratio temperature readout method. The obtained relative sensitivity exhibited high values in the physiological range, from 3.5 %K−1 at 300 K to 2.9 %K−1 at 330 K, above 2 %K−1 below 400 K and above 1 %K−1 between 400 K and 540 K.

Purpose This study compared the dose enhancement predicted in kilovoltage gold nanoparticle-enhanced radiotherapy using the newly developed EGS lattice and the typical gold-water mixture method in Monte Carlo simulation. This new method considered the gold nanoparticle-added volume consisting of solid nanoparticles instead of a gold-water mixture. In addition, this particle method is more realistic in simulation. Methods A heterogeneous phantom containing bone and water was irradiated by the 105 and 220 kVp x-ray beams. Gold nanoparticles were added to the tumour volume with concentration varying from 3–40 mg/mL in the phantom. The dose enhancement ratio (DER), defined as the ratio of dose at the tumour with and without adding gold nanoparticles, was calculated by the gold-water mixture and particle method using Monte Carlo simulation for comparison. Results It is found that the DER was 1.44–4.71 (105 kVp) and 1.27–2.43 (220 kVp) for the gold nanoparticle concentration range of 3–40 mg/mL, when they were calculated by the gold-water mixture method. The DER was slightly larger and equal to 1.47–4.84 (105 kVp) and 1.29–2.5 (220 kVp) for the same concentration range, when the particle method was used. Moreover, the DER predicted by both methods increased with an increase of nanoparticle concentration, and a decrease of x-ray beam energy. Conclusion The deviation of DER determined by the particle and gold-water mixture method was insignificant when considering the uncertainty in the calculation of DER (2%) in the nanoparticle concentration range of 3–40 mg/mL. It is therefore concluded that the gold-water mixture method could predict the dose enhancement as accurate as the newly developed particle method.

An electric virtual impactor with a capability of sampling fine and ultrafine particles was developed and its performance was evaluated both numerically and experimentally. The electric virtual impactor was provided with metallic electrodes, to which electric voltage in the range of 75–9000 V was applied for creating an electric field within the virtual impactor. Particle electric mobility was utilized to sample ultrafine particles at the major outflow section, while particle inertia was employed to collect fine particles at the minor outflow section. Silver nanoparticles with known charge level and Arizona test dust were used to experimentally validate the performance of the electric virtual impactor. Numerical and experimental outcomes agreed well with each other. The upper cutoff size of the electric virtual impactor was fixed at about 2.6 μm, while the lower cutoff size varied from 7 nm to 110 nm depending on the applied electric voltage. As a result, the proposed electric virtual impactor was able to sample both fine and ultrafine particles of a desired particle size range.

Quantitative characterization of the pore structure and gas seepage characteristics of loaded coal is of great significance to the study of high-efficiency gas drainage in coal seams. Aiming at the problem of imperfect characterizations of coal seepage characteristics based on nuclear magnetic resonance (NMR), a calculation method for the pore permeability of coal with different pore diameters is proposed. The pore structure and seepage characteristics of coal have been quantitatively studied using a nuclear magnetic resonance (NMR) system. The results show that with increasing external load, the proportion of the pore volume of the coal sample in the range of 0.01-0.52 μm gradually decreases, while that in the range of 5.11-352.97 μm increases. In this process, the porosity increases from 0.9967 to 1.0103%, the connectivity increases from 0.1718 to 0.2391, and the permeability increases from 2.64 × 10-6 to 8.20 × 10-6 μm2. The calculation of the coal sample connectivity and permeability using the improved NMR permeability component proves that 94.37-352.97 μm pores are the main channel of fluid flow. When the axial pressure increases, the coal body permeability in the aperture range of 94.37-352.97 μm rapidly increases. The improved permeability component calculation model can better reflect the variation law of pore permeability of the loaded coal body.

This letter proposes a force sensor that combines semiconductor strain gauges and metallic foil strain gauges to present force information of a higher dynamic range to robots. The strain gauges have different sensitivities, with semiconductor strain gauge sensitivity being approximately 90-fold than that of the metallic foil strain gauges. Using this difference in sensitivity, large forces and small forces are both detected through the two types of strain gauges and high dynamic range force detection is achieved by combining the output signals of these two. It was confirmed from the SN ratio test that the proposed sensor has a measurement range from 0.005 N to 1000 N, the maximum load. The dynamic range is 2 $\times 10^5$ , extending the dynamic range of the 6-axis force sensor with the highest range in previous studies two-fold.

Pulsed beams containing O and O2 with incident velocities of ∼7900 m s−1 were directed at a carbon fiber preform network (FiberForm) at temperatures in the range, 1023–1823 K, and the products that scattered from the network were detected with a rotatable mass spectrometer as a function of their velocities and scattering angles. A beam containing pure Ar atoms was also directed at the network, allowing multiple-bounce effects in the absence of reaction to be characterized. Scattered O, O2, and Ar exhibited the dynamical characteristics of impulsive (non-thermal) scattering and thermal desorption (TD). On the other hand, CO and CO2 exhibited only TD dynamics. The fluxes of all products were quantified as a function of sample temperature and, for two focus temperatures, as a function of scattering angle. CO was the dominant reactive product. A temperature dependent hysteresis in the CO flux was quantified, and a comparison was made between the hysteresis on the carbon fiber network and on a planar vitreous carbon surface. The new results may be used to increase the fidelity of oxygen-carbon ablation models for hypersonic flight.

The radial distribution functions of aqueous solutions of praseodymium chloride in a wide range of concentrations under standard conditions were calculated from the experimental data obtained earlier by XRD analysis. The results were analyzed using a model approach. The quantitative characteristics of the nearest environment of Pr3+ and Cl– ions were determined: coordination numbers, interparticle distances, and types of ion pairs. At higher concentration, the average number of water molecules decreases from 9 to 6.2 in the first coordination sphere of the cation and from 14.4 to 4.2 in the second. It was concluded that the structure of a dilute solution is determined by an ion pair of the noncontact type, which transforms into an ion triplet at increased concentrations.

This paper reports on a method for producing ceramics from a high-purity, submicron InGaO3(ZnO)2 powder synthesised using a PVA-assisted gel combustion method, as well as an experimental study of the thermophysical properties of the ceramic materials obtained. The platelet-like crystallites of the InGaO3(ZnO)2 obtained were several microns long and up to several hundred nanometres thick. Layered ceramics obtained by sintering compacted InGaO3(ZnO)2 powders at temperatures of 1373–1773 K had a bulk density that was 68–96 % of the theoretical density. The temperature dependence of heat capacity in the range 306–1346 K was studied experimentally for InGaO3(ZnO)2 using the DSC method. It was found that, in the range 323–1173 K, layered InGaO3(ZnO)2 ceramics had a low thermal conductivity, which decreased from 2.0–1.3 W/(m K. The results obtained make it possible to consider this material as a promising thermal barrier coating.

The behavior of the (TiCr1.8)xV100 – x intermetallic system in the reaction of hydrogen evolution in 1 M KOH solution has been studied by polarization measurements and electrochemical impedance spectroscopy. Cathodic polarization curves and impedance spectra were obtained in the potential range corresponding to the linear region of the log i–E dependence. All investigated alloys have two linear sections on the cathodic polarization curves. The two sections of the potential dependence are also revealed in other electrochemical parameters of the system. Impedance spectroscopy allowed establishing that no thick oxide film is present on the alloys’ surfaces. For the analysis of the obtained impedance spectra, three equivalent electrical circuits were applied, in order to describe the electrochemical hydrogen evolution. The parameters of the Faraday impedance were calculated. Assumptions about the hydrogen evolution reaction behavior according to the Volmer–Heyrovsky mechanism and Temkin adsorption isotherm were made.

Time-resolved small- and wide-angle X-ray scattering (SAXS/WAXS) studies of proteins in solution based on the pump-probe approach unveil structural information from intermediates over a broad range of length and time scales. In spite of the promise of this methodology, only a fraction of the wealth of information encoded in scattering data has been extracted in studies performed thus far. Here, we discuss the methodology, summarize results from recent time-resolved X-ray scattering studies, and examine the potential to extract additional information from these scattering curves.

The energy of combustion of polyethylene oxime is determined for the first time via combustion calorimetry. The resulting experimental data are used to calculate the standard enthalpy of combustion and thermochemical characteristics of the formation of a partially crystalline polymer at T = 298.15 K, along with the thermodynamic characteristics of its synthesis in the range of 298.15–400 K.

This paper reports experimental results of the continuous mobility spectrum and mean mobility of corona ions by using a Gerdien tube and the integral equation method. The effects of voltage polarity, nominal electric field on the conductor surface, temperature, humidity and airborne suspended particles on the mobility spectrum and mean mobility are studied. The results show that the positive and negative mean ion mobilities are 1.06 -1.20 cm2V−1s−1 and 1.74-2.04 cm2V−1s−1, respectively, when the temperature is 25 °C and the relative humidity (RH) is 20%. The electric field on conductor surface has little impact on the mean ion mobility in the range of +23.1-+28.2 kV/cm and -20.5–25.6 kV/cm, while increasing temperature and humidity leads to a decrease of the negative mean ion mobility. The results also show that airborne suspended particles have impacts on the mean ion mobility and mobility spectrum, and the impacts are density reliant, which are ascribable to the capture of ions by particles, leading to the variation of the weights of all ion species in the spectrum.

In this work, series of novel metatitanate ceramics mixed with SnO2 (BTO, STO, BTO@SnO2, STO@SnO2) have been successfully prepared via the solid-state reaction route. The XRD patterns indicate that the BTO, BTO@SnO2 crystallized into the tetragonal structure, where a cubic structure was obtained for STO and STO@SnO2 ceramics. The refinement of the data revealed a variation in lattice parameters of the ceramics. The optical properties were analyzed by using an ultra–visible spectrophotometer. The results showed that values of optical band gap Eg are in the range of 3.0–3.3 eV for all ceramics. Moreover, the radiation shielding factors were reported and the results demonstrated that there is a decreasing tendency in the linear attenuation coefficient (LAC) as the energy changes from 0.2234 to 2.506 MeV. From the LAC results, the BaTiO3 ceramic is the most influential at blocking radiation. The half-value layer (HVL) was examined and we found a notable difference between the HVL of the four prepared ceramics. BTO has the least HVL and takes the range 0.725–4.53 cm between 0.2234 and 2.506 MeV. HVL minimum value is obtained at 0.2234 MeV for all compositions and equals 0.725, 0.895, 1.559, and 1.265 cm for BaTiO3, BTO@SnO2, STO, and STO@SnO2 respectively. The change in the transmission factor (TF) of the fabricated ceramics against the energy and the thickness is discussed, and we found that the four ceramics have the minimum TF at 0.2234 MeV and the greatest at 2.506 MeV. The TF for BTO is 56.31% at 0.2234 MeV, 73.76% at 0.356 MeV, 80.25% at 0.511 MeV and 91.3% at 2.506 MeV. The TF results suggest that the fabricated ceramics are good attenuators at low energies. The radiation shielding results confirmed that the prepared ceramics can be exploited as good candidates for radiation shielding applications.

Powder compaction is a complex manufacturing process, even though the procedural description is simple. While different methods are used in the literature, it is still challenging to understand the governing principles. It is especially challenging for empirical studies to investigate particle-level interactions. Thus, computational analyses are required for particle-level understanding. A wide range of computational methods has been developed, such as the discrete element method (DEM) and the multi-particle finite element method (MPFEM), to characterize powder compaction at the particle level. However, a limited number of studies in the literature have analyzed powder compaction using the 3D multi-particle finite element method. Historically, these studies focus only on solid particles. The compaction behavior of hollow spheres, common to pharmaceutical spray drying, was investigated both computationally and experimentally. In the computational analysis, two different particle sizes with different shell-thicknesses were examined using the 3D multi-particle finite element method. In the experimental study, polymer hydroxypropyl methylcellulose acetate succinate (HPMCAS) particles spray-dried at two different outlet temperatures (45 °C and 80 °C) were used. The results showed that particle diameter/shell-thickness (d/w) plays an essential role in powder compaction behavior. Regardless of the particle size, reducing shell-thickness reduced the required global axial stress to reach equivalent levels of relative density. However, with a constant ratio of d/w, changes to particle size (d) did not significantly influence the global compaction behavior. Similar results were observed in experimental studies. Simulation results showed that thinner-shell particles yield early in the compaction stage. Additionally, both experimentally and computationally, a spherical hollow particle buckling effect was observed. In summary, this study provides new information on how powder compaction behavior was influenced by particle size and particle shell-thickness.

This article aims to understand the pitch angle distributions (PADs) of the charged particles in the Earth’s inner magnetosphere using test-particle simulations. The emphasis is on characterizing the variation in pitch angle of the charged particles trapped along the Earth’s magnetic field lines. These charged particles undergo gyration, bounce, and azimuthal drift motions in the Earth’s inner magnetosphere. They are trapped until their pitch angle falls into the loss-cone to get lost into the upper atmosphere. We have developed a three-dimensional test-particle simulation model in which the relativistic equation of motion is solved numerically to track these trapped particle’s trajectories. We have examined the pitch angle distributions of the electron, proton, and oxygen for the cases where adiabatic invariants are conserved and non-conserved. For this purpose, we have considered the particle’s trajectory in the latitudinal range of [ - 40 ° , 40 ° ] for one complete drift around the Earth. We found that when adiabatic invariants are conserved, the particles possess butterfly-type pitch angle distributions. Whereas, when adiabatic invariants are not conserved, the particle’s pitch angle distribution bunches toward the 90°-peaked distribution. The situation of non-conservation of adiabatic invariants demonstrated in the present simulation is arising due to larger gyro-radius (few Earth radii) over which the ambient magnetic field is not constant. We have noticed that in the static dipolar magnetic field, all three, 1st, 2nd, and partly 3rd adiabatic invariants are non-conserved when gyro-radius is larger. The information on the change in the pitch angle distribution pattern from butterfly-type to 90°-peak distribution will be useful to understand the pitch angle distributions observed by the recent spacecraft in the Earth’s radiation belts.

We present the results of a joint experimental and theoretical study of plasma expansion arising from Nd:YAG laser ablation (laser wavelength λ = 1.064 μm) of tin microdroplets in the context of extreme ultraviolet lithography. Measurements of the ion energy distribution reveal a near-plateau in the distribution for kinetic energies in the range 0.03-1 keV and a peak near 2 keV followed by a sharp fall-off in the distribution for energies above 2 keV. Charge-state resolved measurements attribute this peak to the existence of peaks centered near 2 keV in the Sn3+-Sn8+ ion energy distributions. To better understand the physical processes governing the shape of the ion energy distribution, we have modelled the laser-droplet interaction and subsequent plasma expansion using two-dimensional radiation hydrodynamic simulations. We find excellent agreement between the simulated ion energy distribution and the measurements both in terms of the shape of the distribution and the absolute number of detected ions. We attribute a peak in the distribution near 2 keV to a quasi-spherical expanding shell formed at early times in the expansion.

We propose an ultra-compact band-pass and band-stop filter with bandwidth tunability based on the loop-cascaded nanobeam structure in simulation, with a small coupling region of $41\times 1\,\,\mu \text{m}^{2}$ . It features low insertion loss, large bandwidth tunable range and high sidelobe suppression ratio. By two-stage cascading, the bandwidth of the band-pass filter can be adjusted in the range of 6 nm-24 nm. We also experimentally demonstrate the loop-cascaded nanobeam band-pass and band-stop filter with a coupling region of only $17.5\times 1\,\,\mu \text{m}^{2}$ .

Hypothesis Suspensions of nanoporous particles in non-wetting fluids (lyophobic nanoporous suspensions, LPNPS) are explored as energy absorbing materials for shock absorbers, bumpers, and energy storage. Upon application of pressure, the non-wetting fluid invades the pores transforming the impact energy into the interfacial energy that can be stored and released on demand. Experiments Here, we present a comprehensive experimental study of the dynamics of LPNPS compression within a wide range of shock impact energy for three types of mesoporous materials (Libersorb 23, Polysorb-1, and Silochrome-1.5) with water and Wood alloy as non-wetting fluids. Findings Three different regimes of the LPNPS compression-expansion cycle in response to the shock impact are distinguished as the impact energy increases: without fluid penetration into the pores, with partial penetration, and with complete pore filling. In two latter regimes, the suspension compressibility in the process of rapid compression increases by 2–4 decimal decades. This giant effect is associated with the onset of penetration of the non-wetting fluid into the nanopores upon achievement of a certain threshold pressure. The dynamic threshold pressure exceeds the threshold pressure of quasistatic intrusion and does not depends on the impact pressure, temperature, and suspension composition. A dynamic model of suspension compression is suggested that allows to separate the effects of the fluid intrusion into the pores and the elastic deformation of the system.

An algorithm is proposed for reconstructing the energy spectra of electron beams in the energy range of 5 to 10 MeV from depth dose distributions in an aluminum phantom, calculated via modeling using the GEANT4 program code. An estimate of the accuracy of the reconstruction of spectra consisting of two monochromatic beams is established that depends on the chosen energy step.

Carboranes are boron-carbon clusters with important applications in fields of materials, catalysis, pharmaceuticals, etc. However, the non-covalent interactions that could determine the solid-state structures and properties of such boron clusters have been rarely investigated. Herein, inspired by the coordinate bond in metallacarborane or ferrocene, the boron cluster-based non-covalent interaction (denoted as cage-···cage- interaction) between two nido-carborane clusters was successfully realized by using a pyridinium-based molecular barrier. The X-ray diffraction studies uncover that the cage-···cage- interaction has a contacting dis-tance of 5.4-7.0 Å from centroid to centroid in the systems reported here. Theoretical calculations validate the formation of the non-covalent interaction and disclose its repulsive bonding nature that is overcome thanks to the positively charged pyridinium-based framework. Interestingly, such bulk crystalline materials containing the cage-···cage- interaction show relevant properties such as full-color absorption in the visible light range and important photothermal effect, which are absent for the control com-pound without carboranes. This study may offer fundamental insights into the boron cluster-based non-covalent interactions and open a new research avenue to rationally design boron cluster-based materials This work has been supported by the Ministerio de Economía y Competitividad (MINECO) of Spain (Projects CTQ2017-85341-P, PID2019-106830GB-I00, PID2020-113711GB-I00, and MDM-2017-0767) and the Generalitat de Catalunya (projects 2017SGR39 and 2017SGR348). Excellent service by the Supercomputer center of the Consorci de Serveis Universitaris de Catalunya (CSUC) is gratefully acknowledged. The authors also gratefully acknowledge the financial support from NSFC (21820102004, 21531004, and 91961104)

P-type point contact (PPC) germanium detectors are used in rare event and low-background searches, including neutrinoless double beta (0νββ) decay, low-energy nuclear recoils, and coherent elastic neutrino-nucleus scattering. The detectors feature an excellent energy resolution, low detection thresholds down to the sub-keV range, and enhanced background rejection capabilities. However, due to their large passivated surface, separating the signal readout contact from the bias voltage electrode, PPC detectors are susceptible to surface effects such as charge build-up. A profound understanding of their response to surface events is essential. In this work, the response of a PPC detector to alpha and beta particles hitting the passivated surface was investigated in a multi-purpose scanning test stand. It is shown that the passivated surface can accumulate charges resulting in a radial-dependent degradation of the observed event energy. In addition, it is demonstrated that the pulse shapes of surface alpha events show characteristic features which can be used to discriminate against these events.

Photo-chemical conversion of CO2 into solar fuels by photocatalysts is a promising and sustainable strategy in response to the ever-increasing environmental problems and imminent energy crisis. However, it is unavoidably impeded by the insufficient active site, undesirable inert charge transfer and fast recombination of photogenerated charge carriers on semiconductor photocatalysts. In this work, all these challenges are overcome by construction of a novel defect-engineered Z-scheme hybrid photocatalyst, which is comprised of three-dimensional (3D) BiOBr nanoflowers assembled by nanosheets with abundant oxygen vacancies (BiOBr-VO) and two-dimensional (2D) HNb3O8 nanosheets (HNb3O8 NS). The special 3D-2D architecture structure is beneficial to preventing photocatalyst stacking and providing more active sites, and the introduced oxygen vacancies not only broaden the light absorption range but also enhance the electrical conductivity. More importantly, the constructed Z-scheme photocatalytic system could accelerate the charge carriers transfer and separation. As a result, the optimal BiOBr-VO/HNb3O8 NS (50%-BiOBr-VO/HNb3O8 NS) shows a high CO production yield of 164.6 μmol·g−1 with the selectivity achieves to 98.7% in a mild gas-solid system using water as electron donors. Moreover, the BiOBr-VO/HNb3O8 NS photocatalyst keeps high photocatalytic activity after five cycles under the identical experimental conditions, demonstrating its excellent long-term durability. This work provided an original strategy to design a new hybrid structure photocatalyst involved VOs, thus guiding a new way to further enhance CO2 reduction activity of photocatalyst.

A way of processing complex X-ray and gamma spectra in the 10–100 keV energy range is proposed. It considers the complexity of describing X-ray lines and ensures a processing error of ≤1%. It is used to study LX-components of the radiation of an 241Am calibration source. The yields of the main gamma quanta are determined with an accuracy of 1–4%.

In this communication, a high-gain planar antenna with a conical beam (CB) is presented for millimeter-wave drone applications. The proposed antenna comprises a vertical monopole and a circular side reflectors. The high-gain CB is achieved by in-phase reflections from the planar annular-distributed side reflectors which is realized by a series of via walls using the printed-circuit-board (PCB) fabrication. The proposed structure was numerically and experimentally demonstrated. Full-wave analysis shows a 10 dB impedance bandwidth (BW) of 26.50–29.96 GHz, corresponding to 12.26% of the fractional BW, whereas the measured data account for 11.6% in the frequency range of 26.63–29.91 GHz. Meanwhile, a maximum peak gain of 8.51 dBi is observed at a beam-pointing angle of 22°, with a high radiation efficiency of 88.3%. Owing to these valuable features of high gain, good CB radiation performance, and simple planar structure, the proposed antenna is a promising candidate for millimeter-wave drone applications.