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Based on the panel data of 30 provinces from 2010 to 2020, this paper explores the energy-saving and emission reduction effects and action paths of green finance development from the perspective of energy efficiency and energy consumption structure . The results show that green finance has a significant effect on energy-saving and emission reduction. Green finance not only effectively promotes the improvement of energy efficiency, but also promotes the optimization and upgrading of energy consumption structure; Further analysis shows that there are regional differences in the energy efficiency and energy consumption structure of green finance in terms of energy-saving and emission reduction. The potential of green finance in energysaving and emission reduction in the central and western regions is significantly greater than that in the eastern regions; In addition, green finance also has a heterogeneous impact on energy efficiency and energy consumption structure at different quantile levels. At the level of energy efficiency, the dividend period of green finance's energy-saving and emission reduction effect is relatively short, and the potential of green finance's energy-saving and emission reduction effect in adjusting the energy consumption structure is huge. The mechanism analysis found that green technology innovation and industrial structure optimization played a partial intermediary role in the impact of green finance on energy-saving and emission reduction,and green finance has a greater effect on energy conservation and emission reduction at the level of energy consumption structure through industrial structure optimization.

Symmetry and topology are central to understanding quantum Hall ferromagnets (QHFMs), two-dimensional electronic phases with spontaneously broken spin or pseudospin symmetry whose wavefunctions also have topological properties.sup.1,2. Domain walls between distinct broken-symmetry QHFM phases are predicted to host gapless one-dimensional modes--that is, quantum channels that emerge because of a topological change in the underlying electronic wavefunctions at such interfaces. Although various QHFMs have been identified in different materials.sup.3-8, interacting electronic modes at these domain walls have not been probed. Here we use a scanning tunnelling microscope to directly visualize the spontaneous formation of boundary modes at domain walls between QHFM phases with different valley polarization (that is, the occupation of equal-energy but quantum mechanically distinct valleys in the electronic structure) on the surface of bismuth. Spectroscopy shows that these modes occur within a topological energy gap, which closes and reopens as the valley polarization switches across the domain wall. By changing the valley flavour and the number of modes at the domain wall, we can realize different regimes in which the valley-polarized channels are either metallic or develop a spectroscopic gap. This behaviour is a consequence of Coulomb interactions constrained by the valley flavour, which determines whether electrons in the topological modes can backscatter, making these channels a unique class of interacting one-dimensional quantum wires. QHFM domain walls can be realized in different classes of two-dimensional materials, providing the opportunity to explore a rich phase space of interactions in these quantum wires. Scanning tunnelling microscopy shows that 1D channels between quantum Hall states with different valley polarization are metallic or insulating depending on constraints imposed on electron-electron interaction by valley flavour., Author(s): Mallika T. Randeria [sup.1] , Kartiek Agarwal [sup.2] , Benjamin E. Feldman [sup.1] [sup.5] [sup.6] , Hao Ding [sup.1] , Huiwen Ji [sup.3] , R. J. Cava [sup.3] , [...]

As a promising candidate for solid-state electrolytes in Li-ion batteries, the garnet-type Li-ion conductor series Li5+xLa3Nb2−xZrxO12 (LLNZO) (0 ≤ x ≤ 2) exhibits high ionic conductivity at room temperature. However, no previous single-crystal growth or characterization has been reported for LLNZO compositions 0 ≤ x ≤ 1. To obtain a complete understanding of the trend in the structure–property relationship in this class of materials, we used the floating zone (FZ) method to grow a single crystal of Li5.5La3Nb1.5Zr0.5O12 that was 4 mm in diameter and 10 mm in length. Using Laue neutron single-crystal diffraction, two distinct Li sites were observed: tetrahedral 24d and octahedral 96h sites. The maximum entropy method (MEM) based on neutron single-crystal diffraction data was used to map Li nuclear density and estimate that the bottleneck of Li transport exists between neighboring tetrahedral and octahedral sites, and that Li is delocalized between split octahedral sites. Room-temperature Li-ion conductivity in Li5.5La3Nb1.5Zr0.5O12 measured with electrochemical impedance spectroscopy (EIS) was 1.37 × 10−4 S cm−1. The Li migration activation energy was estimated to be 0.50 eV from EIS and 0.47 eV from dielectric relaxation measurements. The Li-ion jump attempt rate was estimated to be 1.47 × 1012 Hz while the time scale of successful migration is 10−7 to 10−6 s. [ABSTRACT FROM AUTHOR]

Cloud and cloud shadow detection are essential in remote sensing imagery applications. Few semantic segmentation models were designed specifically for clouds and their shadows. Based on the visual and distribution characteristics of clouds and their shadows in remote sensing imagery, this paper provides a multi-supervised feature fusion attention network. We design a multi-scale feature fusion block (FFB) for the problems caused by the complex distribution and irregular boundaries of clouds and shadows. The block consists of a fusion convolution block (FCB), a channel attention block (CAB), and a spatial attention block (SPA). By multi-scale convolution, FCB reduces excessive semantic differences between shallow and deep feature maps. CAB focuses on global and local features through multi-scale channel attention. Meanwhile, it fuses deep and shallow feature maps with non-linear weighting to optimize fusion performance. SPA focuses on task-relevant areas through spatial attention. With the three blocks above, FCB alleviates the difficulties of fusing multi-scale features. Additionally, it makes the network resistant to background interference while optimizing boundary detection. Our proposed model designs a class feature attention block (CFAB) to increase the robustness of cloud detection. The network achieves good performance on the self-made cloud and shadow dataset. This dataset is taken from Google Earth and contains remote sensing imagery from several satellites. The proposed model achieved a mean intersection over union (MIoU) of 94.10% on our dataset, which is 0.44% higher than the other models. Moreover, it shows high generalization capability due to its superior prediction results on HRC_WHU and SPARCS datasets. [ABSTRACT FROM AUTHOR]

Author(s): Cheng Gong [1]; Lin Li [2]; Zhenglu Li [3, 4]; Huiwen Ji [5]; Alex Stern [2]; Yang Xia [1]; Ting Cao [3, 4]; Wei Bao [1]; Chenzhe Wang [1]; [...]

Laser-induced breakdown spectroscopy (LIBS) is a rapid and simple analytical method that provides qualitative and quantitative elemental information of samples without damaging them and does not require any sample preparation. Recently, an increasing number of studies have used LIBS to detect aerosols. This technique meets the requirements to be used in some practical applications, such as atmospheric monitoring and industrial processes. However, the unique properties of aerosols bring a level of uncertainty to the LIBS signals of the samples, which is an obstacle to overcome. This review attempts to summarize the relevant research regarding aerosol-LIBS, including the various apparatuses, conditional analysis methods, effects of plasma–particle interactions, means for improving signal intensity, and applications. [ABSTRACT FROM AUTHOR]

Fluorine substitution is a critical enabler for improving the cycle life and energy density of disordered rocksalt (DRX) Li‐ion battery cathode materials which offer prospects for high energy density cathodes, without the reliance on limited mineral resources. Due to the strong Li–F interaction, fluorine also is expected to modify the short‐range cation order in these materials which is critical for Li‐ion transport. In this work, density functional theory and Monte Carlo simulations are combined to investigate the impact of Li–F short‐range ordering on the formation of Li percolation and diffusion in DRX materials. The modeling reveals that F substitution is always beneficial at sufficiently high concentrations and can, surprisingly, even facilitate percolation in compounds without Li excess, giving them the ability to incorporate more transition metal redox capacity and thereby higher energy density. It is found that for F levels below 15%, its effect can be beneficial or disadvantageous depending on the intrinsic short‐range order in the unfluorinated oxide, while for high fluorination levels the effects are always beneficial. Using extensive simulations, a map is also presented showing the trade‐off between transition‐metal capacity, Li‐transport, and synthetic accessibility, and two of the more extreme predictions are experimentally confirmed. [ABSTRACT FROM AUTHOR]

We describe the previously unreported oxygen excess hexagonal antimony tungsten bronze is reported, with a composition of Sb0.5W3O10, in the following denoted as h‐SbxWO3+2x with x=0.167, to demonstrate its analogy to classical AxWO3 tungsten bronzes. This compound forms in a relatively narrow temperature range between 580 °C

We report a new, cleavable, strong topological metal, Zr2Te2P, which has the same tetradymite-type crystal structure as the topological insulator Bi2Te2Se. Instead of being a semiconductor, however, Zr2Te2P is metallic with a pseudogap between 0.2 and 0.7 eV above the Fermi energy (EF). Inside this pseudogap, two Dirac dispersions are predicted: one is a surface-originated Dirac cone protected by time-reversal symmetry (TRS), while the other is a bulk-originated and slightly gapped Dirac cone with a largely linear dispersion over a 2 eV energy range. A third surface TRS-protected Dirac cone is predicted, and observed using angle-resolved photoemission spectroscopy, making Zr2Te2P the first system, to our knowledge, to realize TRS-protected Dirac cones at M points. The high anisotropy of this Dirac cone is similar to the one in the hypothetical Dirac semimetal BiO2. We propose that if EF can be tuned into the pseudogap where the Dirac dispersions exist, it may be possible to observe ultrahigh carrier mobility and large magnetoresistance in this material. [ABSTRACT FROM AUTHOR]

The hallmark of a topologically insulating state of matter in two dimensions protected by time-reversal symmetry is the existence of chiral edge modes propagating along the perimeter of the sample. Among the first systems predicted to be a two-dimensional topological insulator are bilayers of bismuth. Here we report scanning tunnelling microscopy experiments on bulk Bi crystals that show that a subset of the predicted Bi-bilayers' edge states are decoupled from the states of the substrate and provide direct spectroscopic evidence of their one-dimensional nature. Moreover, by visualizing the quantum interference of edge-mode quasi-particles in confined geometries, we demonstrate their remarkable coherent propagation along the edge with scattering properties consistent with strong suppression of backscattering as predicted for the propagating topological edge states. [ABSTRACT FROM AUTHOR]

Highlights: [•] The introduction of Bi stabilizes α-In2Se3 and facilitates the crystal growth. [•] Optical measurements show an indirect band gap. [•] Transport measurements show semiconducting temperature dependence. [ABSTRACT FROM AUTHOR]

A previously unreported compound, Ag0.79VS2, has been synthesized; its structure and elementary properties are reported. Ag0.79VS2 crystallizes in two forms, designated as the α and β, related to the 1s-InTaS2 structure. Single crystal x-ray diffraction shows the α form to have a single layer hexagonal structure with a unit cell of 3.213(3)Å×7.809(6)Å, consisting of layers of edge-shared VS6 triangular prisms separated by layers of Ag. The β form is similar but has an supercell in the basal plane, yielding a unit cell of 5.573(5)Å×7.822(6)Å. Both forms have disordered and displaced silver in the basal plane, but the β form has partial ordering of its silver sublattice and in-plane vanadium trimers. Resistivity measurements show metallic temperature dependence with an unusual hysteresis between 210K and 130K. Magnetic susceptibility measurements show Pauli Paramagnetic behavior. The Seebeck coefficient at 300K is 42µV/K. [ABSTRACT FROM AUTHOR]

We report spin- and angle-resolved photoemission studies of a topological semimetal from the infinitely adaptive series between elemental Bi and Bi2Se3. The compound, based on Bi4Se3, is a 1:1 natural superlattice of alternating Bi2 layers and Bi2Se3 layers; the inclusion of S allows the growth of large crystals, with the formula Bi4Se2.6S0.4. The crystals cleave along the interfaces between the Bi2 and Bi2Se3 layers, with the surfaces obtained having alternating Bi or Se termination. The resulting terraces, observed by photoemission electron microscopy, create avenues suitable for the study of one-dimensional topological physics. The electronic structure, determined by spin- and angle-resolved photoemission spectroscopy, shows the existence of a surface state that forms a large, hexagonally shaped Fermi surface around the Γ point of the surface Brillouin zone, with the spin structure indicating that this material is a topological semimetal. [ABSTRACT FROM AUTHOR]

Cr2Ge2Te6 is proposed as an insulating ferromagnetic substrate for the growth of tetradymite-type topological insulators, based on a refined characterization of its transport, magnetic, optical, and calculated electronic properties. It is found to be a soft ferromagnet with no visible magnetic domains over relatively large length scales and to be highly insulating with an indirect band gap and low carrier concentration. Further we present the fabrication of Bi2Te3-Cr2Ge2Te6 heterostructure samples by chemical vapor deposition and show that crystals of the two phases are oriented such that the hexagonal Te planes are aligned at their interfaces. [ABSTRACT FROM AUTHOR]