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Abstract The AMBRE experiment onboard the ocean topography mapper JASON‐3 aims at measuring the spacecraft potential as well as auroral particle precipitation using two top‐hat analyzers for electrons and ions in the 20 eV–28 keV energy range. The JASON‐3 spacecraft has a nearly circular orbit at an altitude of 1,336 km with an inclination of 66°, at times probing the equatorward part of the auroral oval in a nearly tangential manner upon leaving the outer radiation belt. In this region of space, during periods of enhanced geomagnetic activity with small or moderate storms, AMBRE detected recurrent “microinjections” of ions with energies in the 200 eV–28 keV range and which exhibit clear time‐of‐flight dispersion. Ray tracing using single trajectory computations suggests that these ions are launched from a source located in the 8,000–12,000 km altitudinal range and subsequently propagate downward toward the ionosphere. Such observations of quasiperiodic dispersed downflowing ions are new, and we argue that these structures could be produced by ion‐wave interactions at midaltitudes.
Landau, L.D. & E.M, LifSic. Course of theoretical physics. 5. Landau, L.D. & E.M. Lifšic, Statisti- cal physics. 1958. 6. Landau, L.D. & E.M. Lifèic, Fluid mechanics. 1959. 7. Landau, L.D. & E.M. Lif&ic, Theory of elasticity. 1959. 8. Landau, L.D. & E.&. Lif^ic, Electro- dynamics of continuous media. I960.
Landau, L.D. & E.M. Lifäic. Course of theoretical physics. 1. Landau, L.D. & E.M. Lifšic, Mechanics, 1960. 2. Landau, L.D, & E.M. Lifšic, The classi- cal theory of fields. Rev, 2 ed. 1962. 3. Landau, L.D. & E.M. Lifšic, Quantum mechanics. 1958. 4. Bere sTecTt 1,1, VTB'. m. f 1., Relat i vis t i c quantum theory. P. 1. 1972.
Abstract The cleanliness of ultrahigh-strength steels (UHSSs) without and with electroslag remelting (ESR) using a slag with the composition of 70% CaF2, 15% Al2O3, and 15% CaO was studied. Three experimental heats of UHSSs with different chemical compositions were designed, melted in an induction furnace, and refined using ESR. Cast ingots were forged at temperatures between 1100 and 950°C, air cooled, and their non-metallic inclusions (NMIs) were characterized using field emission scanning electron microscopy and laser scanning confocal microscopy. Thermodynamic calculations for the expected NMIs formed in the investigated steels with and without ESR were performed using FactSage 7.2 software while HSC Chemistry version 9.6.1 was used to calculate the standard Gibbs free energies (ΔG°). As a result of ESR the total impurity levels (TIL% = O% + N% + S%) and NMI contents decreased by as much as 46 % and 62 %, respectively. The NMIs were classified into four major classes: oxides, sulphides, nitrides, and complex multiphase inclusions. ESR brings about large changes in the area percentages, number densities, maximum equivalent circle diameters, and the chemical composition of the various NMIs. Most MnS inclusions were removed although some were re-precipitated on oxide or nitride inclusions leading to multiphase inclusions with an oxide or nitride core surrounded by sulphide, e.g. (MnS.Al2O3) and (MnS. TiN). Also, some sulphides are modified by Ca forming (CaMn)S and CaS.Al2O3. Some nitrides like TiN and (TiV)N are nucleated and precipitated during the solidification phase. Al2O3 inclusions were formed as a result of the addition of Al as a deoxidant to the ESR slag to prevent penetration of oxygen to the molten steel.
Abstract The optical properties of several commonly used single-crystal oxide substrates were explored by spectroscopic ellipsometry over a wide spectral range from 0.74 eV to 8.8 eV. The crystals examined are (100) SrTiO3, 0.7 % wt Nb-doped (100) SrTiO3,(100) (LaAlO3)0.29(SrAl0.5Ta0.5O3)0.7, (011) DyScO3, (100) MgAl2O4, (100) MgO, and (100) LaAlO3, all of which enable epitaxial growth of numerous perovskite-type and other optical thin films. An analytic form for the complex dielectric function was derived from ellipsometric data through a physically consistent modeling process. The obtained dielectric spectra were further utilized to calculate the complex index of refraction and absorption coefficient for each substrate material. The absorption spectra and optical band gap were analyzed using Tauc plots. The parameters for reconstructing the dielectric functions are given in detail, allowing for extensive applications of the results of this work.
Abstract The electronic, thermodynamic, and optical properties of a new type of two-dimensional Janus layer (JL) consisting exclusively of chalcogens are investigated using first-principles calculations. The permutations on atomic sites provide increased stability due to the multi-valency of chalcogens, and a heavier central atom further stabilizes the layer due to the increased coordination number. The investigated JLs are indirect bandgap materials with a bandgap larger than 1.23 eV, making them suitable for photocatalytic activity. Different feasible chemical potentials are analyzed, and chalcogens’ poor limits are proposed to fabricate the JLs. Based on the comparison of the formation energy, the energetic profile of the JLs is identified as EfTeSeS < E fSSeTe < EfSeSTe, irrespective of the chemical potentials of chalcogen. Hence, TeSeS is more stable than the JL arrangements SSeTe and SeSTe. The flat bands around the Fermi energy level and the reduction in path length between the maximum of conduction and minimum of valence bands explain the magnitude of multiple peaks observed in the optical spectra of the JLs. These absorptions turn the studied JLs into potential candidates for water splitting. The optimized bandgap reveals that the band edges efficiently straddle the water redox potentials at different pH levels. In addition, the positive vibrational frequencies depict the stability of these layers. Because of the minimal formation energy requirement, higher density of states around the Fermi level, as well as enhanced optical absorption compared to other JL, TeSeS JLs may lead to enhanced performance in photovoltaic and photocatalytic applications. These results add new members to the JL family of pure chalcogens and pave the way toward novel materials for respective applications.
Abstract Ferroelectric films may lose polarization as their thicknesses decrease to a few nanometers because of the depolarizing field that opposes the polarization therein. The depolarizing field is minimized when electrons or ions in the electrodes or the surface/interface layers screen the polarization charge or when peculiar domain configuration is formed. Here, we demonstrate ferroelectric phase transitions using thermooptical studies in ∼5-nm-thick epitaxial Pb0.5Sr0.5TiO3 films grown on different insulating substrates. By comparing theoretical modeling and experimental observations, we show that ferroelectricity is stabilized through redistribution of charge carriers (electrons or holes) inside ultrathin films. The related high-density of screening carriers is confined within a few-nanometers-thick layer in the vicinity of the insulator, thus resembling a two-dimensional carrier gas.
Abstract The effect of the probe ring size in OTA test systems was studied based on simulations and OTA measurements in the anechoic chamber of the University of Oulu. The results are presented for two methodologies: Prefaded Synthesis (PFS) and Plane Wave Synthesis (PWS). Each size and synthesis type was validated for UMI and Uma radio channel models and for the cases the DUT in free space and in phantom hand.
Abstract The influence of vibronic coupling on the outer valence ionic states of cis-dichloroethene has been investigated by recording photoelectron spectra over the excitation range 19–90 eV using plane polarized synchrotron radiation, for two polarization orientations. The photoelectron anisotropy parameters and electronic state branching ratios derived from these spectra have been compared to theoretical predictions obtained with the continuum multiple scattering approach. This comparison shows that the photoionization dynamics of the à 2B2, B̃ 2A1, C̃ 2A2, and D̃ 2B1 states, all of which are formed through the ejection of an electron from a nominally chlorine lone-pair orbital, exhibit distinct evidence of the Cooper minimum associated with the halogen atom. While retaining a high degree of atomic character, these orbital ionizations nevertheless display clear distinctions. Simulations, assuming the validity of the Born-Oppenheimer and the Franck-Condon approximations, of the X̃ 2B1, à 2B2, and D̃ 2B1 state photoelectron bands have allowed some of the vibrational structure observed in the experimental spectra to be assigned. The simulations provide a very satisfactory interpretation for the X̃ 2B1 state band but appear less successful for the à 2B2 and D̃ 2B1 states, with irregularities appearing in both. The B̃ 2A1 and C̃ 2A2 state photoelectron bands exhibit very diffuse and erratic profiles that cannot be reproduced at this level. Photoelectron anisotropy parameters, β, have been evaluated as a function of binding energy across the studied photon energy range. There is a clear step change in the β values of the à 2B2 band at the onset of the perturbed peak intensities, with β evidently adopting the value of the B̃ 2A1 band β. The D̃2B1 band β values also display an unexpected vibrational level dependence, contradicting Franck-Condon expectations. These various behaviors are inferred to be a consequence of vibronic coupling in this system.
Abstract A spring-fall asymmetry is observed in daytime amplitude values of very low frequency (VLF) radio wave signals propagating over the North Atlantic during 2011–2019. We explore the processes behind this asymmetry by comparing against mesospheric mean temperatures and the semidiurnal solar tide (S2) in mesospheric winds. The solar radiation influence on VLF subionospheric propagation was removed from the daytime VLF amplitude values, isolating the fall-effect. Similarly, the symmetric background level was removed from mesospheric mean temperatures undertaking comparable analysis. During fall, all three analyzed parameters experience significant deviation from their background levels. The VLF amplitude variation during spring is explained by the seasonal variation in solar illumination conditions, while the fall-effect can be interpreted as a mean zonal wind reversal associated with both a S2 enhancement, and temperature reductions. Decreases in temperature can produce decreases in collision frequency, reducing VLF signal absorption, driving the observed VLF asymmetry.
Abstract Caribou (Rangifer tarandus) rely on the short Arctic growing season to restore body condition, support the demands of lactation, and prepare for the long arctic winter, making them susceptible to even small changes in forage availability or quality. Body condition in the summer and autumn is linked to winter survival rates and fecundity in cows, critical factors in the productivity of caribou populations. Climate change predictions of warmer and wetter northern winters suggest increased snowfall over Alaska’s North Slope, which has recently been verified between 1995 and 2017. However, a comprehensive analysis of how deeper snow will affect caribou forage quality is absent across Alaska. In this study, we quantify how snow depth alters the quality and seasonality of caribou forage using a long-term (24 yr) International Tundra Experiment snow depth manipulation to evaluate how winter climate change scenarios may affect tussock tundra systems in northern Alaska. Deeper snow in prior winters leads to increases in growing season leaf N and digestible protein (DP) in deciduous shrubs (Salix spp. and Betula spp.) and graminoids (Carex spp. and Eriophorum spp.), but not evergreen dwarf shrubs (Rhododendron spp. and Vaccinium spp.). Dry matter digestibility varied among species with small differences (<5%) associated with snow depth. Most striking was the discovery that deeper snow in the prior winter increased the duration of DP levels above the minimum threshold for protein gain in caribou by as much as 25 d in Salix pulchra and 6–9 d in Betula nana and Carex bigelowii in late summer and early autumn. Consequently, deeper winter snow may provide an extended window of opportunity for foraging and the accumulation of lean body mass and fat reserves which promote winter survival and successful calving the following spring and potentially improve the productivity of caribou in northern Alaska.
Chemical modifications of RNA provide an additional, epitranscriptomic, level of control over cellular functions. N-6-methylated adenosines (m6As) are found in several types of RNA, and their amounts are regulated by methyltransferases and demethylases. One of the most important enzymes catalyzing generation of m6A on mRNA is the trimer N-6-methyltransferase METTL3-14-WTAP complex. Its activity has been linked to such critical biological processes as cell differentiation, proliferation, and death. We used in silico-based discovery to identify small-molecule ligands that bind to METTL3-14-WTAP and determined experimentally their binding affinity and kinetics, as well as their effect on enzymatic function. We show that these ligands serve as activators of the METTL3-14-WTAP complex.
Abstract Oxidative protein folding in the endoplasmic reticulum is catalyzed by the protein disulfide isomerase family of proteins. Of the 20 recognized human family members, the structures of eight have been deposited in the PDB along with domains from six more. Three members of this family, ERp18, anterior gradient protein 2 (AGR2) and anterior gradient protein 3 (AGR3), are single-domain proteins which share sequence similarity. While ERp18 has a canonical active-site motif and is involved in native disulfide-bond formation, AGR2 and AGR3 lack elements of the active-site motif found in other family members and may both interact with mucins. In order to better define its function, the structure of AGR3 is required. Here, the recombinant expression, purification, crystallization and crystal structure of human AGR3 are described.
Abstract This paper characterizes the impacts of sudden stratospheric warmings (SSWs) and mesospheric coolings (MCs) on the light species distribution (i.e., helium [He], and atomic hydrogen [H]) of the thermosphere using a combined data‐modeling approach. Performing a set of numerical experiments with a general circulation model whose middle atmospheric dynamical and thermodynamical fields were constrained using a numerical weather prediction system, we simulate the effects of SSWs and MCs on light chemical species, and via comparisons with two data sets taken from the mesosphere and thermosphere, we quantify the associated variability in light species abundances and mass density. Large depletions in the observed and modeled polar H abundance in the mesosphere and lower thermosphere (MLT) occur with MC onset, as opposed to SSW onset. Depletions in all light thermospheric species at high northern latitudes extend up to the exobase in our model simulations during the January 2013 SSW/MC period, with the largest depletions simulated for the lightest species. Further, our modeling work substantiates the paradigm of increased mixing in the MLT driven by a meridional residual circulation during SSWs resulting from enhanced small‐scale gravity wave and migrating semidiurnal tidal forcing; the former being the primary driver and the latter of secondary but notable importance in our model simulations. SSW/MC induced light species variability then gets projected upward into the thermosphere through molecular diffusion. Modeled light species variability during the January 2013 SSW/MC event suggests SSW/MC signatures could be present in the topside ionosphere and plasmasphere.
Abstract Linearly polarized synchrotron radiation has been used to record polarization dependent valence shell photoelectron spectra of imidazole in the photon energy range 21–100 eV. These have allowed the photoelectron angular distributions, as characterized by the anisotropy parameter β, and the electronic state intensity branching ratios to be determined. Complementing these experimental data, theoretical photoionization partial cross sections and β-parameters have been calculated for the outer valence shell orbitals. The assignment of the structure appearing in the experimental photoelectron spectra has been guided by vertical ionization energies and spectral intensities calculated by various theoretical methods that incorporate electron correlation and orbital relaxation. Strong orbital relaxation effects have been found for the 15a’, nitrogen lone-pair orbital. The calculations also predict that configuration mixing leads to the formation of several low-lying satellite states. The vibrational structure associated with ionization out of a particular orbital has been simulated within the Franck–Condon model using harmonic vibrational modes. The adiabatic approximation appears to be valid for the X 2A′′ state, with the β-parameter for this state being independent of the level of vibrational excitation. However, for all the other outer valence ionic states, a disparity occurs between the observed and the simulated vibrational structure, and the measured β-parameters are at variance with the behavior expected at the level of the Franck–Condon approximation. These inconsistencies suggest that the excited electronic states may be interacting vibronically such that the nuclear dynamics occur over coupled potential energy surfaces.
Using a relativized diquark model Hamiltonian, we calculate the masses of JPC=0++ ground-state tetraquarks in the following systems: bsb¯s¯, bbn¯n¯ (n=u,d), bbs¯s¯, ccc¯c¯, bbb¯b¯, bcb¯c¯ and bbc¯c¯. We also compute extensive spectra for the fully-heavy quark flavour combinations. Finally, as a test of the diquark model approach, we compute the masses of fully-heavy baryons in the diquark model. Our results may be compared soon to the forthcoming experimental data for fully-heavy three-quark systems.
[Introduction] The title compound, C 14 H 16 N 6 O 2 , is a second monoclinic polymorph of 2-[1-(3,5-dimethyl)pyrazolyl]-2-hydroxyimino- N 0 -[1-(2-pyridyl)ethylidene] acetohydrazide, with two crystal- lographically independent molecules per asymmetric unit. The non-planar molecules are chemically equal having similar geometric parameters. The previously reported polymorph [Plutenko et al. (2012). Acta Cryst. E 68 , o3281] was described in space group Cc ( Z = 4). The oxime group and the O atom of the amide group are anti with respect to the C—C bond. In the crystal, molecules are connected by N—H N hydrogen bonds into zigzag chains extending along the b axis.
Abstract The valence shell photoelectron spectrum of cis-dichloroethene has been studied both experimentally and theoretically. Photoelectron spectra have been recorded with horizontally and vertically plane polarized synchrotron radiation, thereby allowing the anisotropy parameters, characterizing the angular distributions, to be determined. The third-order algebraic-diagrammatic construction approximation scheme for the one-particle Green’s function has been employed to compute the complete valence shell ionization spectrum. In addition, the vertical ionization energies have been calculated using the outer valence Green’s function (OVGF) method and the equation-of-motion coupled-cluster, with single and double substitutions for calculating ionization potentials (EOM-IP-CCSD) model. The theoretical results have enabled assignments to be proposed for most of the structure observed in the experimental spectra, including the inner-valence regions dominated by satellite states. The linear vibronic coupling model has been employed to study the vibrational structure of the lowest photoelectron bands, using parameters obtained from ab initio calculations. The ground state optimized geometries and vibrational frequencies have been computed at the level of the second-order Møller-Plesset perturbation theory, and the dependence of the ionization energies on the nuclear configuration has been evaluated using the OVGF method. While the adiabatic approximation holds for the X̃ 2B1 state photoelectron band, the à 2B2, B̃ 2A1, and C̃ 2A2 states interact vibronically and form a complex photoelectron band system with four distinct maxima. The D̃ 2B1 and Ẽ 2B2 states also interact vibronically with each other. The potential energy surface of the D̃ 2B1 state is predicted to have a double-minimum shape with respect to the out-of-plane a2 deformations of the molecular structure. The single photoelectron band resulting from this interaction is characterized by a highly irregular structure, reflecting the non-adiabatic nuclear dynamics occurring on the two coupled potential energy surfaces forming a conical intersection close to the minimum of the Ẽ 2B2 state.
Abstract This paper presents a planar wideband dual-polarized antenna structure integrated on PCB (Printed Circuit Board). The patch itself is fed by a capacitive coupling with two smaller patches, one for each polarization. Whereas the simulations predicts 24–40 GHz, -10 dB impedance bandwidth. The measured one shows 24.75–42.75 GHz bandwidth. The results are corresponding to 50% relative -10 dB impedance bandwidth. The patch antenna is on the ground plane of size 4.7 mm x 4.7 mm, and the corners of the ground plane are cut to gain better XPD (cross polarization discrimination). The manufactured prototype antenna is measured and simulated with a 50 Ω coaxial line. Simulated total efficiency and XPD are presented as a function of frequency. The total efficiency is better than -0.8 dB (83%) efficiency, whereas the simulated XPD is better than 14 dB. The simulated 3D radiation patterns are presented at 24 GHz, 32 GHz, and 40 GHz with gains of 2.8 dBi, 5.0 dBi, and 4.3 dBi, respectively.
Abstract This paper investigates the outage performance of a cooperative relaying network, where the relay node is considered to be an energy-constrained device so that a power splitting-based simultaneous wireless information and power transfer scheme is employed. The relay is considered to operate in full-duplex (FD) mode so that both energy recycling and information decoding can be performed. For this purpose, the relay is assumed to be provided with two batteries which switch between the power supplying mode and charging mode at each transmission block. In particular, we assume that the self-interference inherent to FD mode is not completely suppressed; it is subject only to passive interference cancellation for self-energy recycling, while it is subject to both passive and active cancellation for information decoding. We derive a tight closed-form approximation to the outage probability for the considered FD mode-based scheme, as well as for the HD mode-based counterpart. We validate the obtained expressions via Monte Carlo simulations. The impact of self-energy recycling in FD mode on the system performance is assessed.
Partial resistance to cereal rusts is characterized by reduction in pathogen reproduction despite a susceptible infection type (Parlevliet, 1985). In some pathosystems (e.g. blast in tropical lowland rice) such resistance has proved to be durable (Bonman et al., 1992). To identify oat germplasm with partial resistance to crown rust, caused by Puccinia coronata, a multilocation screening trial was initiated in 2002. Eighty-six entries were tested at 3 locations planted in the fall of 2002 in the southern US and at 5 locations planted in the spring of 2003 in the midwestern US and Canada using at least 2 replications per site. The line MN841804 was the resistant check and cultivars Brooks and Otana were susceptible checks. The resistant check showed an average disease level of 7.5% relative to the susceptible checks across locations. One entry, the cultivar CDC Boyer, may have a useful level of partial resistance for areas less prone to the disease. In the present study it averaged 24.5% disease relative to the checks across locations. CDC Boyer and 26 other lines showing relative severity values between 3% and 25% and low variation between locations were selected for further testing in 2004. Also, adult plants of CDC Boyer, OT389 (12.1% across locations) and IA98822-2 (17.6% across locations), are undergoing greenhouse tests with compatible races of P. coronata. Further field and greenhouse experiments are planned with these and other lines to ascertain if the lower disease level in field trials is correlated with partial resistance assessed in controlled inoculations. Bonman, J.M. et al. 1992. Annual Review Phytopathology 30:507-528; Parlevliet, J.E. 1985. In: Roelfs, A.P. and W.R. Bushnell (eds.) The Cereal Rusts vol. II. New York, Academic Press, Inc. p. 501-525.
Abstract In addition to existing empirical models describing the average distributions of energetic electron precipitation into the auroral ionosphere at different activity levels, we develop and test a semiempirical approach to construct dynamical models describing the recurrent features of spatiotemporal development of auroral absorption in the ionosphere during individual substorms. Its key ingredients are (a) usage of linear prediction filter technique to extract from riometer data the response function to the injection of unit magnitude and (b) characterization of injection parameters by midlatitude magnetic variations caused by the substorm current wedge. Using global riometer network we test the method performance for stations in the middle of auroral zone (at corrected geomagnetic latitudes of 65–67°) where generally the absorption amplitude is largest. In this paper we use the midlatitude positive bay index, recently developed by X. Chu and R. McPherron, to drive the model. We evaluate the model performance, discuss the dynamical properties of energetic electron precipitation as revealed by the linear prediction filter response function analyses, and finally, we discuss possible future improvements of this method intended for both science and applications.
Miniature laser welds with the root depth in the range of 50–300 μm represent air-tight joints between the components in medical devices, such as those in implants, growth rods, stents and various prostheses. The current work focuses on the development of a fatigue test specimen and procedure to determine fatigue lives of shear-loaded laser welds. A cobalt-chromium (CoCr) alloy is used as a benchmark case. S–N graphs, damage process, and fracture surfaces are studied by applying x-ray analysis, atomic force microscopy, and scanning electron microscopy both before and after the crack onset. A non-linear material model is fitted for the CoCr alloy to run finite element simulations of the damage and deformation. As a result, two tensile-loaded specimen designs are established and the performance is compared to that of a traditional torque-loaded specimen. The new generation specimens show less variation in the determined fatigue lives due to well-defined crack onset point and, therefore, precise weld seam load during the experiments. The fatigue damage concentrates to the welded material and the entire weld experiences fatigue prior to the final, fracture-governed failure phase. For the studied weld seams of hardened CoCr, a regression fatigue limit of 10.8–11.8 MPa, where the stress refers to the arithmetic average shear stress computed along the region dominated by shear loading, is determined.
This work includes raw and analyzed test data when using a recently developed fatigue test method for miniature laser welds in cobalt-chromium (CoCr) alloy joints [1]: 10.1016/j.jmbbm.2019.07.004. The automization of fatigue tests is crucial for saving costs and personnel resources and that is the reason why the atomization threshold and the resulting spectrum data related to CoCr welds are provided here. The finite element method based stress computation output is provided related to shearing-mode tests to support the dataset as a whole. In addition, the compositional data of the parent material and the laser weld are given.
Abstract Ground-based observations of 11.072 GHz atmospheric ozone (O3) emission have been made using the Ny-Ålesund Ozone in the Mesosphere Instrument (NAOMI) at the UK Arctic Research Station (latitude 78∘55’0’’ N, longitude 11∘55’59’’ E), Spitsbergen. Seasonally averaged O3 vertical profiles in the Arctic polar mesosphere–lower thermosphere region for night-time and twilight conditions in the period 15 August 2017 to 15 March 2020 have been retrieved over the altitude range 62–98 km. NAOMI measurements are compared with corresponding, overlapping observations by the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) satellite instrument. The NAOMI and SABER version 2.0 data are binned according to the SABER instrument 60 d yaw cycles into nominal 3-month “winter” (15 December–15 March), “autumn” (15 August–15 November), and “summer” (15 April–15 July) periods. The NAOMI observations show the same year-to-year and seasonal variabilities as the SABER 9.6 μm O3 data. The winter night-time (solar zenith angle, SZA ≥ 110∘) and twilight (75∘ ≤ SZA ≤ 110∘) NAOMI and SABER 9.6 μm O3 volume mixing ratio (VMR) profiles agree to within the measurement uncertainties. However, for autumn twilight conditions the SABER 9.6 μm O3 secondary maximum VMR values are higher than NAOMI over altitudes 88–97 km by 47 % and 59 %, respectively in 2017 and 2018. Comparing the two SABER channels which measure O3 at different wavelengths and use different processing schemes, the 9.6 μm O3 autumn twilight VMR data for the three years 2017–2019 are higher than the corresponding 1.27 μm measurements with the largest difference (58 %) in the 65–95 km altitude range similar to the NAOMI observation. The SABER 9.6 μm O3 summer daytime (SZA < 75∘) mesospheric O3 VMR is also consistently higher than the 1.27 μm measurement, confirming previously reported differences between the SABER 9.6 μm channel and measurements of mesospheric O3 by other satellite instruments..
Abstract Phased arrays have typically equal lengths for all antenna paths. This paper compares three phased array architectures for 5/6G applications. The first two arrays present unequal-length feeding networks, while the third array is the corporate-fed one. The first array is fed from the center, while the second is fed from the side. The impacts of the unsymmetrical feeding network on the bandwidths are analyzed and compared to the corporate-fed array. We show that side-fed arrays present higher bandwidths for higher steering angles, while center-fed arrays work better in the broadside region. Moreover, side-fed arrays can also be better than corporate-fed ones near the end-fire region, making them a good alternative to reduce the footprint of the feeding networks. Finally, we illustrate that if the feeding point can be varied as a function of the desired steering angle, the broadband performance of the array can be optimized for different steering angles.
We have measured the response of a torsional oscillator containing polycrystalline hcp solid He to applied steady rotation in an attempt to verify the observations of several other groups that were initially interpreted as evidence for macroscopic quantum effects. The geometry of the cell was that of a simple annulus, with a fill line of relatively narrow diameter in the centre of the torsion rod. Varying the angular velocity of rotation up to 2 rad s showed that there were no step-like features in the resonant frequency or dissipation of the oscillator and no history dependence, even though we achieved the sensitivity required to detect the various effects seen in earlier experiments on other rotating cryostats. All small changes during rotation were consistent with those occurring with an empty cell. We thus observed no effects on the samples of solid He attributable to steady rotation.
The average tungsten concentrations in the pedestal region (cW) predicted by the Monte Carlo code DIVIMP and the coupled multi-fluid plasma/kinetic neutral code EDGE2D-EIRENE are found to agree within a factor of 2 for a range of JET-ILW L-mode and H-mode plasma conditions. Under attached divertor conditions with cW exceeding 10−6, the cW predicted by DIVIMP is consistently ~50% higher than by EDGE2D-EIRENE. In colder plasma scenarios with cW <10-6, stochastic variations exceed the systematic disagreement between the two codes. The average tungsten charge predicted by EDGE2D-EIRENE in the upstream scrape-off layer is lower by 40–50% due to the bundling of the 74 tungsten ion charge states into 6 fluid species, which explains the reduced tungsten accumulation in the main plasma compared to the DIVIMP predictions.
Receiving the qualitative, energy efficient and economic building is the main tendency in the civil engineering. One of the leading places is occupied by technology of frame-panel construction with use of new non-autoclaved, monolithic foamed concrete technology producing on a building site. On the example of the real samples there were determined the heat-shielding properties of foamed concrete in a condition of setting process and after attainment of strength with a practical and theoretical methods. The results were obtained for a non-autoclaved monolithic foamed concrete wall fragment (lightweight steel concrete structure - LSCS) for the areas with and without rigid reinforcement with steel thin-wall profiles (lightweight gauge steel structure - LGSS). Influence of the thermal bypass on cold-resisting properties of enclosure structures with technology "Intech LB" is revealed. On the basis of the received results, modernization of a design for improvement of its thermotechnical characteristics is made.
We study numerically the detailed structure and decay dynamics of isolated monopoles in conditions similar to those of their recent experimental discovery. We find that the core of a monopole in the polar phase of a spin-1 Bose-Einstein condensate contains a small half-quantum vortex ring. Well after the creation of the monopole, we observe a dynamical quantum phase transition that destroys the polar phase. Strikingly, the resulting ferromagnetic order parameter exhibits a Dirac monopole in its synthetic magnetic field. We observe quantitatively matching decay dynamics for both ferromagnetic and antiferromagnetic spin-spin interactions.