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Magnetic liquid metal (LM) soft robots attract considerable attentions because of distinctive immiscibility, deformability and maneuverability. However, conventional LM composites relying on alloying between LM and metallic magnetic powders suffer from diminished magnetism over time and potential safety risk upon leakage of metallic components. Herein, we report a strategy to composite inert and biocompatible iron oxide (Fe3O4) magnetic nanoparticles into eutectic gallium indium LM via reactive wetting mechanism. To address the intrinsic interfacial non-wettability between Fe3O4 and LM, a silver intermediate layer was introduced to fuse with indium component into AgxIny intermetallic compounds, facilitating the anchoring of Fe3O4 nanoparticles inside LM with improved magnetic stability. Subsequently, a miniature soft robot was constructed to perform various controllable deformation and locomotion behaviors under actuation of external magnetic field. Finally, practical feasibility of applying LM soft robot in an ex vivo porcine stomach was validated under in-situ monitoring by endoscope and X-ray imaging. Interfacial non-wettability between biocompatible iron oxide and liquid metal caused by the substantial mismatch in surface energy remains an issue. Here, the authors introduce a silver intermediate layer to reduce compositional mismatch and improve the wetting ability between iron oxide and liquid metal. [ABSTRACT FROM AUTHOR]

Understanding the distribution of soil organic carbon and nitrogen (OC(N)) content, cation exchange capacity (CEC), and specific surface area (SSA) in different soil particle sizes is crucial for studying soil fertility and properties. In this study, we investigated the distribution characteristics of the OC(N), CECand SSA in different particles of yellow–brown soil under different methods. The result revealed that as the particle size decreased, the soil OC(N), SSA and CEC content gradually increase. The content of OC and ON different soil particles ranged from 1.50–28.16 g·kg−1 to 0.18–3.78 g·kg−1, respectively, and exhibited significant differences between different particles. We observed good linear relationships between OC and ON in different particle sizes of yellow–brown soil under different utilization methods, with correlation coefficients ranging from 0.86 to 0.98, reaching a very significant level (n = 12, p < 0.01). The ranges of SSA and CEC in different particles of the four soils were 0.30–94.70 m2·g−1 and 0.70–62.91 cmol·kg−1, respectively. Additionally, we found logarithmic relationships between SSA (CEC) and the equivalent diameter for the four soils, with correlation coefficients (r2) higher than 0.91. Furthermore, there was an extremely significant linear relationship between CEC and SSA of the four soils, with correlation coefficients (r2) of 0.92–0.97 (n = 12, p < 0.01). These results highlight the close relationship between soil particle size and soil OC(N), SSA, and CEC. The conclusions drawn from this study provide valuable data support and a theoretical basis for further understanding soil properties. [ABSTRACT FROM AUTHOR]

In order to keep the microcapsules intact during transportation and storage, the mechanical properties of the microcapsules need to be enhanced, and therefore, we innovatively attached the oxidized carbon nanotubes (CNTs) to the surface of phenolic resin, and CNTs/phenolic resin microcapsules were successfully synthesized by in situ polymerization method. The tests showed that CNTs had been successfully compounded with phenolic resin, and CNTs can effectively improve the mechanical properties of microcapsules with a 16.37% increase in maximum rupture load. This research result was expected to provide positive scientific ideas to solve the problem of early fracture in the airtight wall of the goaf. [ABSTRACT FROM AUTHOR]

Single crystalline BaMnSb2 is considered as a 3D Weyl semimetal with the 2D electronic structure containing Dirac cones from the Sb sheet. We report experimental investigation of low-temperature cleaved BaMnSb2 surfaces using scanning tunneling microscopy/spectroscopy and low energy electron diffraction. By natural cleavage, we find two terminations: one is Ba (above the orthorhombically distorted Sb sheet) and another Sb2 (at the surface of the Sb/Mn/Sb sandwich layer). Both terminations show the 2 × 1 surface reconstructions, with drastically different morphologies and electronic properties, however. The reconstructed structures, defect types and nature of the electronic structures of the two terminations are extensively studied. The quasiparticle interference (QPI) analysis is conducted at the energy range between −2 V and 2 V, although no interesting states are observed near the Fermi level, the surface-projected electronic band structures strongly depend on the surface termination above 1.6 V. The existence of defects can greatly modify the local density of states to create electronic phase separations on the surface in the order of tens of nm scale. Our observation on the atomic structures of the terminations and the corresponding electronic structures provides critical information towards an understanding of topological properties of BaMnSb2. [ABSTRACT FROM AUTHOR]

Background: In elderly, hip fracture is often complicated by perioperative heart failure, related to worse prognosis. We aimed to analyze the effects of integrated management bundle incorporating with multidisciplinary measures on in-hospital outcomes and early survival in elderly hip fracture patients with perioperative heart failure. Methods: In this retrospective cohort study, a total of 421 hip fracture patients aged 65 and over who developed perioperative heart failure were included. According to different perioperative management modes applied, patients were retrospectively divided into multidisciplinary management group (Group A), including 277 patients, and integrated management bundle group (Group B), including 144 patients. The B-type natriuretic peptide (BNP) and C-reactive protein (CRP) levels, complications, length of stay, and hospitalization costs were observed and compared between two groups. Overall survival was compared by Kaplan–Meier methods. Cox regression analysis was used to identify prognostic factors associated with overall survival. Results: A total of 421 patients were enrolled for analysis, including 277 in Group A and 144 in Group B. BNP and CRP levels were significantly decreased compared with admission (P < 0.05). Furthermore, BNP and CRP in Group B decreased much more than those in Group A (P < 0.05). The reductions were observed in length of stay, hospitalization costs and incidence of pulmonary infection, hypoproteinemia, and acute cerebral infarction in Group B (all P < 0.05). The Kaplan–Meier plots showed significantly superior overall survival in Group B. Integrated management bundle was independent favorable prognostic factors. Conclusions: The integrated management bundle incorporating with multidisciplinary measures significantly improved the therapeutic effect of perioperative heart failure, reduced inflammatory response, and yielded better hospital outcomes. It brought better survival benefits for geriatric hip fracture patients with perioperative heart failure. The results of this study can play an important role in clinical work and provide a valuable theoretical basis for selection of management model in elderly hip fracture patients with perioperative heart failure. [ABSTRACT FROM AUTHOR]

The electronic inhomogeneities in Co, Ni, and Cr doped BaFe2As2 single crystals are compared within three bulk property regions: a pure superconducting (SC) dome region, a coexisting SC and antiferromagnetic (AFM) region, and a non-SC region. Machine learning is utilized to categorize the inhomogeneous electronic states: in-gap, L-shape, and S-shape states. Although the relative percentages of the states vary in the three samples, the total volume fraction of the three electronic states is quite similar. This is coincident with the number of electrons (Ni0.04 and Co0.08) and holes (Cr0.04) doped into the compounds. The in-gap state is confirmed as a magnetic impurity state from the Co or Ni dopants, the L-shape state is identified as a spin density wave which competes with the SC phase, and the S-shape state is found to be another form of magnetic order which constructively cooperates with the SC phase, rather than competing with it. [ABSTRACT FROM AUTHOR]

Two-dimensional Janus materials have great potential for the applications in spintronic devices due to their particular structures and novel characteristics. However, they are usually non-magnetic in nature. Here, different transition metals (TMs: Co, Fe, Mn, Cr, and V) adsorbed WSSe frameworks are constructed, and their structures and magnetic properties are comprehensively investigated by first-principles calculations. The results show that the top of W atom is the most stable absorption site for all the TM atoms, and all the systems exhibit magnetism. Moreover, their magnetic properties significantly depend on the adsorbed elements and the adsorbent chalcogens. A maximal total magnetic moment of 6 μB is obtained in the Cr-adsorbed system. The induced magnetism from S-surface-adsorption is always stronger than that for the Se-surface-adsorption due to its larger electrostatic potential. Interestingly, the easy magnetization axis in the Fe-adsorbed system switches from the in-plane to the out-of-plane when the adsorption surface changes from Se to S surface. The mechanism is analyzed in detail by Fe-3d orbital-decomposed density of states. This work provides a guidance for the modification of magnetism in low-dimensional systems. [ABSTRACT FROM AUTHOR]

A ring R is said to be strongly J n -clean if n is the least positive integer such that every element a is strongly J n -clean, that is, there exists an idempotent e such that e a = a e , a - e is a unit and e a n is in the Jacobson radical J(R). It is proved that strongly J n -clean ring is a strongly clean ring with stable range one. If R is an abelian ring (a ring in which all idempotents are central), then R is strongly J n -clean if and only if R / J(R) is strongly π -regular and idempotents lift modulo J(R). Some examples and basic properties of these rings are studied. Some criterions in terms of solvability of the characteristic equation are obtained for such a 2 × 2 matrix to be strongly J 2 -clean. [ABSTRACT FROM AUTHOR]

We investigate the electric-field-dependent optical properties and electronic behaviors of GaS monolayer by using the first-principles calculations. A reversal of the dipole transition from E//c to E⊥c anisotropy is found with a critical external electric field of about 5 V/nm. Decomposed projected band contributions exhibit asymmetric electronic structures in GaS interlayers under the external electric field, which explains the evolution of the absorption preference. Spatial distribution of the partial charge and charge density difference reveal that the strikingly reversed optical anisotropy in GaS ML is closely linked to the additional crystal field originated from the external electric field. These results pave the way for experimental research and provide a new perspective for the application of the monolayer GaS-based two-dimensional electronic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Photodetectors based on photoconductivity effect are usually driven by an external power source. A self-powered photodetector can be powered by incident light using the photovoltaic effect. Here, photoelectrochemical cells with periodically aligned ZnO/CdS nanowire arrays as photoanodes were fabricated and investigated for detecting UV and visible light. At zero bias, this self-powered UV-visible photodetector showed high responsivities of 35.4 and 23.2 mA/W for UV and visible light, a fast rise time of 0.18 s, and a decay time of 0.32 s. The spectral responses of the self-powered photodetectors based on ZnO/CdS nanowire arrays exhibited superior photoresponse in both UV and visible regions in comparison with ZnO nanowire film and ZnO nanowire arrays. The high photosensing performance originates from the excellent light trapping ability at broadband wavelengths and the high charge collection efficiency of the highly ordered ZnO/CdS nanowire arrays. The results indicate that the ZnO/CdS heterojunctions with periodic nanostructures provide a facile frame for UV-visible detecting applications. [ABSTRACT FROM AUTHOR]