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For research the behavior and after effects which had been resulted from the coated reactive fragments impacting the steel targets, the 14.5mm ballistic rifle had been adopted to complete the experiments that the 6mm Q235A steel targets was impacted by the steel fragments and the reactive fragments, composed by metal/ polymer coated with steel, with the same mass and size. Afterwards, the v50 ballistic-limited velocity and the law of the damage effects on the after effect-targets had been discovered. The results indicate that the integral strength of the coated reactive fragments was lower than that of the inert steel fragments, which lead to the reductions of the penetration performance. The v50 ballistic-limited velocity, resulted of the coated reactive fragments impacting the 6mm Q235A steel targets, was 709m/s and it was 1.33 times than that of the steel fragments with the same mass and size. The reaming enhanced effects on the after effect-targets could be produced in the condition that the impact velocity of coated reactive fragments should be greater than 900m/s while the residual velocity should be greater than 181m/s, and that it had been strengthened along with the impact velocity increased. The probable reasons of the damage enhanced effects had been analyzed that the coupled damage effects had been resulted from two parts energy. The results will provide important references to the engineering application of reactive fragments for warheads.

This paper presents measurements gathered with the Gravity Field and Ocean Circulation Explorer (GOCE) satellite, TEC values collected in the American sector, and Poynting Flux (PF) derived using the electric and magnetic fields from the Defense Meteorological Satellite Program (DMSP) satellites aiming to elucidate the mechanisms controlling the initiation of large-scale traveling atmospheric disturbances (LSTAD) and the transit and asymmetry of concurrent large-scale traveling ionospheric disturbances (LSTID). LSTADs and LSTIDs measured during twelve intense magnetic storms that occurred between 2011 and 2013 are thoroughly analyzed. The LSTAD/LSTID appearance and characteristics are correlated against the PF values and the auroral oval’s location, measured by the DMSP satellites. GOCE data and TEC values are used to assess the perturbation of the vertical wind and TEC (∂TEC), inter-hemispheric asymmetry of the appearance of LSTIDs, and the role of the different phases of storms and the structures within interplanetary coronal mass ejections (ICME). Emphasis is devoted to examining LSTADs and LSTIDs during the storms of 5–6 August 2011, 15 July 2012, and 17 March 2013, the supporting material reports on the dynamics of LSTADs and LSTIDs for nine additional storms. During most storms, LSTIDs initiate from both auroral ovals and propagate toward the opposite hemisphere. However, on 5 August 2011 and 15 July 2012, LSTIDs moved only from one hemisphere toward the opposite. Close inspection of the TEC perturbation associated with these events indicates that LSTIDS onsets at opposite hemispheres occur at different times and intensities. This timing delay is produced by the difference in the amount of PF deposited in each hemisphere. It is also indicated that LSTAD’s initiation occurs when the PF is above 1 mW/m2 and when the lower latitude edge of the auroral oval moves equatorward at 65°. In addition, LSTIDs are observed during the passage of ICME sheath (in 6 storms), magnetic clouds (11), and Sunward Loops (1), although they occur when the IMF Bz is predominantly directed southward. The observations suggest that the interhemispheric asymmetries in the LSTIDs initiation, extension, and amplitude occur when the ICME sheath passes, containing rapidly varying IMF Bz sign fluctuations. TEC perturbations associated with the LSTID can be up to 4% of the background TEC value, and the LSTAD neutral density variability measured by GOCE can be up to 8%. LSTIDs are observed during all phases of magnetic storms.

Continents are formed by the amalgamation of numerous micro-terranes and island arcs, so they have spatially varying lithosphere strengths. The crème brûlée (CB) model and the jelly sandwich (JS) model have been commonly used to describe continental lithosphere strength–depth variations. Depending on the strength of the continental lower crust, the CB and JS models can be further subdivided into two subclasses in which the I subclass (CB-I and JS-I) and II subclass (CB-II and JS-II), respectively, have a strong or weak lower crust. During the continental collision, lithosphere deformation is the byproduct of the comprehensive interaction of multiple terranes. Here we used 2-D thermomechanical numerical models that contain three continental terranes to systematically explore the effects of terranes with various strengths on continental deformation and studied the effects of different rheological assumptions on terrane deformation. We found four types of lithosphere deformation patterns: collision, subduction, thickening and delamination, and replacement. These simulation patterns are seen in observed deformation patterns and structures in East Asia, suggesting they are likely to be naturally occurring modes of intracontinental orogenesis.

The mechanism of the charge density wave transition in quasi one-dimensional blue bronzes is still debated. Here, the authors report evidence of a Luttinger liquid in the normal state of blue bronzes and Holstein polarons below the transition temperature, revealing the important role of electron-phonon coupling in the transition.

Topological superconductors are potentially important for future quantum computation, but they are very rare in nature. Here, the authors observe topological surface states acquiring a nodeless superconducting gap with similar magnitude as that of the bulk states in 2M-WS2, suggesting an intrinsic topological superconductor.

The chemical inventory of protoplanetary midplanes is the basis for forming planetesimals. Among them, solid-state reactions based on CO/CO _2 toward molecular complexity on interstellar dust grains have been studied in theoretical and laboratory work. The physicochemical interactions between ice, constituted mainly of H _2 O, and dust surfaces are limited to a few experimental studies focusing on vacuum ultraviolet and cosmic-ray processing. In this work, the erosion of C dust grains induced by X-ray irradiation of H _2 O ice was systematically investigated for the first time. The work aims to provide a better understanding of the reaction mechanism using selectively isotope-labeled oxygen/carbon species in kinetic analysis. Ultrahigh vacuum experiments were performed to study the interstellar ice analog on submicron, thick C dust at ∼13 K. H _2 O or O _2 ice was deposited on the presynthesized amorphous C dust and exposed to soft X-ray photons (250–1250 eV). Fourier-transform infrared spectroscopy was used to monitor in situ the newly formed species as a function of the incident photon fluence. Field emission scanning electron microscopy was used to monitor the morphological changes of (non-)eroded carbon samples. The X-ray processing of the ice/dust interface leads to the formation of CO _2 , which further dissociates and forms CO. Carbonyl groups are formed by oxygen addition to grain surfaces and are confirmed as intermediate species in the formation process. The yields of CO and CO _2 were found to be dependent on the thickness of the carbon layer. The astronomical relevance of the experimental findings is discussed.

The effects of naturally acidified seawater on shell traits were quantified through the comparison of dove snails (Family: Columbellidae) Anachis misera from vent environments with Euplica sp. from non-vent sites in northeastern Taiwan. Samples of A. misera were collected around a shallow vent (24.8341° N, 121.96191° E), which included the east, south, southwest, and northwest sites. An absence of Anachis snails was found in the most acidic north site (pH 7.19–7.25). Based on the similarities of protein expression profiles, the Anachis snails were classified into two groups, i.e., V-South (pH 7.78–7.82) and V-Rest (pH 7.31–7.83). Comparing their shell traits to the non-vent Euplica sp. from Da-xi (DX) and Geng-fang (GF) (pH 8.1–8.2), a difference in shell shape (shell width : shell length) was found, with the populations having more globular shells than the non-vent ones. The means of shell width were significantly different among sites (p < 0.01), with a descending order of GF > DX > V-South and V-Rest. The relationships of shell length to total weight were curvilinear for both Anachis and Euplica snails. The logarithmically transformed slopes differed significantly among sites, and the mean body weight of the GF population was greater than that of the others (p < 0.01). Positive correlations between shell length and shell thickness of body whorl (T1) and penultimate whorl (T2) were only observed in non-vent GF and DX populations. Anachis snails from vent sites were thinner in T1 and T2 compared to the Euplica snails from non-vent sites (p < 0.05). Within each vent group, shell thickness between T1 and T2 was insignificantly different. Between vent groups, T1 and T2 from V-Rest showed a decrease of 10.6 and 10.2%, respectively, compared to V-South ones. The decrease of T1 and T2 between vent Anachis snails and non-vent Euplica snails was as great as 55.6 and 29.0%, respectively. This was the first study to compare snail's morphological traits under varying shallow-vent stresses with populations previously classified by biochemical responses. Overall, the shallow-vent-based findings provide additional information from subtropics on the effects of acidified seawater on gastropod snails in natural environments.

The intrinsic magnetic topological insulator MnBi_{2}Te_{4} exhibits rich topological effects such as quantum anomalous Hall effect and axion electrodynamics. Here, by combining the use of synchrotron and laser light sources, we carry out comprehensive and high-resolution angle-resolved photoemission spectroscopy studies on MnBi_{2}Te_{4} and clearly identify its topological electronic structure. In contrast to theoretical predictions and previous studies, we observe topological surface states with diminished gap forming a characteristic Dirac cone. We argue that the topological surface states are mediated by multidomains of different magnetization orientations. In addition, the temperature evolution of the energy bands clearly reveals their interplay with the magnetic phase transition by showing interesting differences between the bulk and surface states, respectively. The investigation of the detailed electronic structure of MnBi_{2}Te_{4} and its temperature evolution provides important insight into not only the exotic properties of MnBi_{2}Te_{4}, but also the generic understanding of the interplay between magnetism and topological electronic structure in magnetic topological quantum materials.