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This paper presents the two-dimensional (2-D) numerical simulation results of heavy-ion induced reverse drain current degradation and single-event burnout (SEB) in the 1.2-kV rated CoolSiC Trench metal-oxide-semiconductor field-effect transistor (MOSFET). The physics models employed in simulations and critical failure conditions were validated by the heavy-ion irradiation experiments of the commercially available 1.2-kV rated SiC planar-gate MOSFET devices. The CoolSiC Trench MOSFET was proven to behave comparative SEB performance compared with the SiC planar-gate MOSFET. The robustness of the CoolSiC Trench MOSFET with different single buffer layer (SBL) designs against a heavy ion was simulated. Furthermore, the SBL-CoolSiC Trench MOSFET with low carrier lifetime control was investigated. According to the simulation results, the severe degeneration failure tolerance increased to 800 V; the SEB failure tolerance could reach 900 V.

In this article, we investigate Schottky diodes with pure W and W-C alloy metal electrodes. The electrical characteristics of samples were analyzed by comparing the current density–voltage ( ${J} - {V}$ ) and capacitance–voltage ( ${C} - {V}$ ) curves at different annealing temperatures from 400 °C to 900 °C. The ideality factor of W-C alloy diodes annealed at 400 °C was 1.162. When W-C alloy diodes were annealed at 500 °C–900 °C, the range of $\emptyset _{B}^{I-{V}}$ was merely 0.08 eV, the ideality factors were below 1.15, and the difference between $\emptyset _{B}^{I-{V}}$ and $\emptyset _{B}^{C-{V}}$ was smaller compared to the pure W diodes. For W-C alloy diodes annealed at 500 °C, the barrier height fluctuated only slightly, and the leakage current was suppressed effectively as the operating temperature increased. These results show that the new structure has better electrical characteristics and thermal stability. Meanwhile, transmission electron microscope (TEM) and energy-dispersive X-ray (EDX) images also verify that W-C alloy diodes reduce the interface reaction between the metal and silicon carbide (SiC), which improves the barrier inhomogeneity of W-based Schottky diodes effectively.

The concept of topological gyrogroups is a generalization of a topological group. In this work, ones prove that a topological gyrogroup Gis metrizable iff Ghas an ωω-base and Gis Fréchet–Urysohn. Moreover, in topological gyrogroups, every (countably, sequentially) compact subset being strictly (strongly) Fréchet–Urysohn and having an ωω-base are all weakly three-space properties with Ha closed L-subgyrogroup.

Some results between the properties of strongly topological gyrogroups and the properties of their remainders are established. In particular, if a strongly topological gyrogroup Gis non-locally compact and Ghas a first-countable remainder, then χ(G)≤ω1, ω(G)≤2ωand |bG|≤2ω1. Moreover, it is proved that the property of paracompact p-space of a strongly topological gyrogroup Gis equivalent with Ghaving a Lindelöf remainder in a compactification. By this result, we prove that if His a dense subspace of a strongly topological gyrogroup Gwhich is locally pseudocompact and not locally compact, then every remainder of His pseudocompact. Furthermore, if a strongly topological gyrogroup Ghas countable pseudocharacter and Gis non-metrizable, then all remainders of Gare pseudocompact. These two results give partial answers to a question posed by Arhangel’ skiǐ and Choban, see (Topol Appl 157:789–799, 2010, Problem 5.1). Finally, it is shown that the Lindelöf property of a non-locally compact strongly topological gyrogroup Gis equivalent with having a remainder with subcountable type for some compactifications of G.

Carabranolides present characteristic NMR resonances for the cyclopropane moiety, which distinctly differ from those of other compounds and were used for an NMR-guided isolation in this study. As a result, 11 undescribed carabranolides (1–11), along with five known ones (12–16), were isolated from the fruits of Carpesium abrotanoidesL. Compounds 1–11are new esters of carabrol at C-4 with different carboxylic acids. Their structures were elucidated by HRESIMS and NMR spectroscopic data analysis. The biological evaluation showed that compounds 2–4, 15, and 16exhibited significant inhibitory activity against LPS-induced NO release with an IC50value of 5.6–9.1 μM and dose-dependently decreased iNOS protein expression in RAW264.7 cells.

Abstract

Residual strain often occurs in metal when it was subjected to the tension load, random vibration, or high impact. The mild steel was selected as the research object, and the feasibility of using nonlinear ultrasonic technique to characterize the residual strain was investigated in this paper. First, the mild steel specimens were stretched to several different kinds of stress, then the nonlinear effect as well as the microstrain of each sample was measured. The results indicate that the microstrain increases with increasing applied stress and reaches a maximum value of about 0.036% as the tensile stress increases to the elastic limit. Compared with the original specimen, the nonlinear parameter of tensile specimen gradually increased within the elastic limit. This result reveals that the variation of nonlinear parameter was related to microstrain in mild steel, because the microstructure observation demonstrated that the dislocation structure was basically unchanged within the elastic limit. This research indicates that the nonlinear ultrasonic method has the promising potential to characterize the microstrain in metals.

To control the pure electric vehicle motors vibration and noise, the dynamic characteristics of the motor are analyzed. Dynamic characteristic include the natural frequency and response characteristics of different parts of the motors structural member. This paper uses three-dimensional software Pro/E modeling of the motor: By making appropriate assumptions and equivalent treatment of the motors stator, rotor core and coil winding, establish the finite element simulation model of the various components .Using the finite element analysis software Workbench analyzes the windings and motor model modal analysis, to get natural frequency of each mode. To make a modal analysis test, we can use hammering method done on the motor. By using real-time signal analyzer AWA6291 make spectral analysis of the motor online, comprehensive comparative analysis of the results and used to guide motor design.

Symmetrical (phthalocyaninato)copper(II) complexes Cu(Pc′) [Pc′ = Pc(15C5), Pc(opp-15C5)2, Pc(adj-15C5)2, Pc(15C5)3; Pc = unsubstituted phthalocyaninate, Pc(15C5) = 2,3-(15-crown-5)phthalocyaninate, Pc(opp-15C5)2 = 2,3,16,17-bis(15-crown-5)phthalocyaninate, Pc(adj-15C5)2 = 2,3,9,10-bis(15-crown-5)phthalocyaninate, Pc(15C5)3 = 2,3,9,10,16,17-tris(15-crown-5)phthalocyaninate] (2–5) have been prepared by the reaction of corresponding heteroleptic bis(phthalocyaninato)europium complexes Eu(Pc)(Pc′) [Pc′ = Pc(15C5), Pc(opp-15C5)2, Pc(adj-15C5)2, Pc(15C5)3, Pc(15C5)4; Pc = unsubstituted phthalocyaninate] with Cu(OAc)2 in dry dmf at 100 °C. For the purpose of comparative studies, the symmetrical counterparts CuPc (1) and CuPc(15C5)4 [Pc(15C5)4 =2,3,9,10,16,17,24,25-tetrakis(15-crown-5)phthalocyaninate](7) have also been prepared. These monomeric complexes have been characterized by spectroscopic methods in addition to elemental analysis. Having a series of closely related phthalocyanines with a different number and/or disposition of 15-crown-5 groups at the peripheral positions, the effects of 15-crown-5 substituent number and molecular symmetry on the electronic absorption spectra, infra-red (IR) spectra, and supramolecular structure formation induced by K+ ions have been investigated. Systematic studies on the formation of dimeric supramolecular structures of the series of monomers 2–6 reveal and confirm the previously proposed two-step three-stage process of K+-induced dimerization of phthalocyanines with three or four 15-crown-5 moieties.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

The mixed double-decker EuPc15C54TPP 1 was obtained by base-catalysed tetramerisation of 4,5-dicyanobenzo-15-crown-5 using the half-sandwich complex EuTPPacac acac acetylacetonate, generated in situ, as the template. For comparative studies, the mixed triple-decker complexes Eu2Pc15C54TPP22 and Eu2Pc15C542TPP 3 were also synthesised by the raise-by-one-story method. These mixed ring sandwich complexes were characterised by various spectroscopic methods. Up to four one-electron oxidations and two one-electron reductions were revealed by cyclic voltammetry CV and differential pulse voltammetry DPV. As shown by electronic absorption and infrared spectroscopy, supramolecular dimers SM1and SM3 were formed from the corresponding double-decker 1and triple-decker 3in the presence of potassium ions in MeOHCHCl3.

The mixed double-decker Eu[Pc(15C5)₄](TPP) (1) was obtained by base-catalysed tetramerisation of 4,5-dicyanobenzo-15-crown-5 using the half-sandwich complex Eu(TPP)(acac) (acac = acetylacetonate), generated in situ, as the template. For comparative studies, the mixed triple-decker complexes Eu₂[Pc(15C5)₄](TPP)₂ (2) and Eu₂[Pc(15C5)₄]₂(TPP) (3) were also synthesised by the raise-by-one-story method. These mixed ring sandwich complexes were characterised by various spectroscopic methods. Up to four one-electron oxidations and two one-electron reductions were revealed by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). As shown by electronic absorption and infrared spectroscopy, supramolecular dimers (SM1 and SM3) were formed from the corresponding double-decker 1 and triple-decker 3 in the presence of potassium ions in MeOH/CHCl₃.

Exposure to high temperatures (heatwaves) is rapidly emerging as an important issue of climate change, in particular for female mammals during lactation. High temperatures adversely affect the ability to dissipate heat, which has negative effects on reproductive output. The cumulative effects on growth of F1 offspring after weaning, and future reproductive performance of offspring, remain uncertain. In this study, F1 mice weaned from mothers lactating at 21 and 32.5°C were housed at 21°C from day 19 until day 56 of age, during which food intake and body mass were measured. The F1 adult females that were weaned at the two temperatures were bred and then exposed to 32.5°C during lactation. Energy intake and milk output, and litter size and mass, were determined. The F1 adults weaned at 32.5°C consumed less food and had lower body mass than their counterparts weaned at 21°C. Several visceral organs or reproductive tissues were significantly lower in mass in F1 weaned at 32.5°C than at 21°C. The exposure to 32.5°C significantly decreased energy intake, milk output and litter mass in F1 adult females during lactation. The F1 adult females weaned at 32.5°C produced less milk and raised lighter pups than those previously weaned at 21°C. The data suggest that transient exposure to hot temperatures during lactation has long-lasting impacts on offspring, including stunted growth and decreases in future reproductive performance when adult. This indicates that the offspring of females previously experiencing hot temperatures have a significant fitness disadvantage.

Abstract: A new diamide N,N,N′,N′-tetrahexylmalonamide (THMA) was synthesized, characterized and used in the extraction of U(VI) from nitric acid solutions. N,N,N′,N′-tetrabutylmalonamide (TBMA) was also studied to test the steric hindrance. Factors affecting this extraction system, the concentration of the extractant, aqueous nitric acid and NaNO3 and the temperature were investigated. The IR spectral study was also made of the extracted species.