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Domain walls (DWs) in the charge-density-wave (CDW) Mott insulator 1T-TaS2 have unique localized states, which play an important role in exploring the electronic properties of the material. However, the electronic states in DWs in 1T-TaS2 have not been clearly understood, mostly due to the complex structures, phases, and interlayer stacking orders in the DW areas. Here, we explored the electronic states of DWs in large-area CDW phase and mosaic phase of 1T-TaS2 by scanning tunneling spectroscopy. Due to the different density of DWs, the electronic states of DWs show distinct features in these phases. In large area CDW phase, both the domain and the DWs (DW1, DW2, DW4) have zero conductance at the Fermi level; while in mosaic phase, they can be metallic or insulating depending on their environments. In areas with high density of DWs, some electronic states were observed both on the DWs and within the domains, indication delocalized states over the whole region. Our work contributes to further understandings on the interplay between CDW and electron correlations in 1T-TaS2.

Charge density wave (CDW) strongly affects the electronic properties of two-dimensional (2D) materials and can be tuned by phase engineering. Among 2D transitional metal dichalcogenides (TMDs), VTe2 was predicted to require small energy for its phase transition and shows unexpected CDW states in its T-phase. However, the CDW state of H-VTe2 has been barely reported. Here, we investigate the CDW states in monolayer (ML) H-VTe2, induced by phase-engineering from T-phase VTe2. The phase transition between T- and H-VTe2 is revealed with x-ray photoelectron spectroscopy (XPS) and scanning transmission electron microscopy (STEM) measurements. For H-VTe2, scanning tunneling microscope (STM) and low-energy electron diffraction (LEED) results show a robust 2 3 × 2 3 CDW superlattice with a transition temperature above 450 K. Our findings provide a promising way for manipulating the CDWs in 2D materials and show great potential in its application of nanoelectronics.

HoBi single crystal and polycrystalline compounds with NaCl-type structure are successfully obtained, and their magnetic and magnetocaloric properties are studied in detail. With temperature increasing, HoBi compound undergoes two magnetic transitions at 3.7 K and 6 K, respectively. The transition temperature at 6 K is recognized as an antiferromagnetic-to-paramagnetic (AFM–PM) transition, which belongs to the first-order magnetic phase transition (FOMT). It is interesting that the HoBi compound with FOMT exhibits good thermal and magnetic reversibility. Furthermore, a large inverse and normal magnetocaloric effect (MCE) is found in HoBi single crystal in the H||[100] direction, and the positive ΔS M peak reaches 13.1 J/kg⋅K under a low field change of 2 T and the negative ΔS M peak arrives at –18 J/kg⋅K under a field change of 5 T. These excellent properties are expected to be applied to some magnetic refrigerators with special designs and functions.

We report a facile phase conversion method that can locally convert n-type SnSe2 into p-type SnSe by direct laser irradiation. Raman spectra of SnSe2 flakes before and after laser irradiation confirm the phase conversion of SnSe2 to SnSe. By performing the laser irradiation on SnSe2 flakes at different temperatures, it is found that laser heating effect induces the removal of Se atoms from SnSe2 and results in the phase conversion of SnSe2 to SnSe. Lattice-revolved transmission electron microscope images of SnSe2 flakes before and after laser irradiation further confirm such conversion. By selective laser irradiation on SnSe2 flakes, a pattern with SnSe2/SnSe heteostructures is created. This indicates that the laser induced phase conversion technique has relatively high spatial resolution and enables the creation of micron-sized in-plane p–n junction at predefined region.

The linkage structures between monomers make great influence on the properties of polymers. The synthesis of some special linkage structures can be challenging, which is often overcome by employing special reaction conditions. Here,we build dihydropentalene linkage in poly-naphthalocyanine on Ag(110) surface. Scanning tunneling microscopy (STM) and non-contact atomic force microscopy (nc-AFM) measurements confirm the dihydropentalenelinkage structure and a possible formation path with reconstruction steps is proposed. The controlled experiment on Ag(100) surface shows no dihydropentalene structures formed, which indicates the grooved substrate is necessary for the reconstruction. This work provides insights into the surface restricted reactions that can yield special structures in organic polymers.

Two-dimensional (2D) materials received large amount of studies because of the enormous potential in basic science and industrial applications. Monolayer Pd2Se3 is a fascinating 2D material that was predicted to possess excellent thermoelectric, electronic, transport, and optical properties. However, the fabrication of large-scale and high-quality monolayer Pd2Se3 is still challenging. Here, we report the synthesis of large-scale and high-quality monolayer Pd2Se3 on graphene-SiC (0001) by a two-step epitaxial growth. The atomic structure of Pd2Se3 was investigated by scanning tunneling microscope (STM) and confirmed by non-contact atomic force microscope (nc-AFM). Two subgroups of Se atoms have been identified by nc-AFM image in agreement with the theoretically predicted atomic structure. Scanning tunneling spectroscopy (STS) reveals a bandgap of 1.2 eV, suggesting that monolayer Pd2Se3 can be a candidate for photoelectronic applications. The atomic structure and defect levels of a single Se vacancy were also investigated. The spatial distribution of STS near the Se vacancy reveals a highly anisotropic electronic behavior. The two-step epitaxial synthesis and characterization of Pd2Se3 provide a promising platform for future investigations and applications.

An antagonistic bacteriastrain was isolated and purified from soybean using Alternaria alternataasindicator. There sultsofmorpho logical identification and 16S rDNA sequencing analysis showed the antagonistic bacteria belongs to Bacillus subtilis. The culture solution of this strain showed an inhibition rate of 73.19% against A. alternata. The strain also showed strong antagonistic action againstBotrytis cinerea, Fusarium graminearum, Lasiodiplodiatheobromae, Botrytis erythraea, Mucor circinelloidesand Aspergillus niger.

In this paper, we report on a type of SU-8 microstructure with vertical sidewalls used for polydimethydiloxane (PDMS) microchannels. Multi-layer lithography using focal plane changing approach is proposed to expose the SU-8 photoresist based on a digital micromirror device (DMD) maskless lithography system. We used a light-emitting diode source with a wavelength of 405 nm. The thickness of the SU-8 is divided into multi-layers according to the depth of focus. Each layer corresponds to a depth of focus, and then, a virtual mask is designed for the layer. Finally, each layer is exposed to changes in the focal plane. The results indicate that the actual profile of the SU-8 mold shows good agreement with the design profile without any T-profiles. Additionally, there is better linewidth in the proposed method compared with multi-exposure by a single fixed focal plane. The PDMS microchannels result also demonstrate the stability of the SU-8 mold.

This paper aims to improve the model of the hydro-turbine system under the effect of water-hammer for frequency-domain studies. It brings out a novel way to overcome the accuracy limitation linked to the simple first and second-order approximations of the gate-turbine transfer function. The proposed study is based on the detailed model of the hydraulic system considering the effects of water compressibility and pipe elasticity. The improved system is controlled using particle-swarm optimization algorithm, which is shown to be very efficient in controlling the overshoot and stability of the system connected to a single machine single load test system. Step response and load disturbance are simulated. Results from our example prove that covering accurately a frequency range from 0 to over 30Hz is easily made when using this method for frequency-domain simulations of hydropower plant load-frequency control.

The processes of methane combustion on three Pd-based diatomic catalysts (Pd2, PdPt and PdNi) are investigated by using density functional theory (DFT) at the B3LYP/6-311++G(d,p)+SDD//B3LYP/6-311G(d,p)+LANL2DZ level. The optimized geometric structures, activation energy (Ea ), and reaction rate constant (k) of methane dehydrogenation and oxidation on Pd2, PdPt and PdNi are compared. The main reaction path for methane combustion on catalyst Pd2 is CH4→CH3→CH2→CHOH→CHO→CO→CO2. However, the main reaction paths on catalyst PdPt and PdNi are the same: CH4→CH3→CH2OH→CHOH→CHO→CO→CO2. The rate-determining steps (RDS) on catalyst Pd2 and PdPt are the same: CHOH→CHO, while the step of CH3→CH2OH is the RDS on PdNi. Further analysis shows that the catalytic activity followed the order of PdPt (k = 1.0639×104 s−1) > Pd2 (k = 1.7281×102 s−1) > PdNi (k = 1.9235×10 s−1). Thus, PdPt catalyst exhibits better performance than the other two catalysts in the methane catalytic combustion.

Bulk SnSe is an excellent thermoelectrical material with the highest figure-of-merit value of ZT = 2.8, making it promising in applications. Temperature-dependent electrical and thermoelectrical properties of SnSe nanoplates are studied at low temperature. Conductivity drops and rises again as temperature is lowered. The Seebeck coefficient is positive at room temperature and becomes negative at low temperature. The change of the sign of the Seebeck coefficient indicates influence of bipolar transport of the semiconductive SnSe nanoplate. The bipolar transport is caused by the Fermi energy changing with temperature due to different contributions from donors and acceptors at different temperatures.

The fast fault point transfer technology has been widely used in China. Aimed at the single-phase arc-grounding fault in the neutral point non-effective grounding system, the principle is to suppress arc re-burning by grounding the faulty phase bus directly to limit the voltage of fault phase. However, the on-site operation found that the technology could not guarantee the arc on the fault point extinguished reliably. The effects of arc characteristics, bus grounding time, impedance of lines, load current and transition resistance on arc extinguishing are analysed in depth. Among these factors, the grounding time is the only controllable factor. The improvement measure of grounding the faulty phase bus at the zero point of the arc current is proposed, and the hardware and software flow are designed. The proposed method was simulated and analysed by ATP software. The simulation results verified the reliability and accuracy of the proposed method.

In order to monitor the rehabilitation training of stroke patients in unsupervised situation and provide rehabilitation advice for rehabilitation clinicians, a wearable wireless motion recognition system has been developed using 9-axis wearable sensors, to identify patients' typical upper limb movements, e.g. Bobath handshake, stretch elbow and press hand, shoulder joint horizontal outreach, elbow buckling contact, paraplegia hand touch the shoulder, sequine pressure rotary before supination. After the original data is collected and preprocessed, each rehabilitation training action is segmented. Dynamic Time Warping (DTW) algorithm is used to calculate the similarity between each motion segment and the standard template data, and the motion recognition is carried out according to the calculated results. To verify the performance of the system, 20 stroke patients were recruited as volunteers. Each patient wore a 9-axis wearable sensor on his upper limb and performed six rehabilitation training exercises. After motion segmentation, 1400 motion fragments were obtained and used as samples to test the system. It has been found that the recognition accuracy of the system for the six rehabilitation training exercises is over 90%. This result provides a well reference for further development of an automated system for stroke patient rehabilitation motion recognition.

The insulating character of the spin-Peierls cuprate is investigated by adopting a modified linear combination of atomic orbitals (LCAO) band method both within the local spin-density approximation (LSDA) and using the strong-correlation correction . It is shown that the strongly orbital-dependent exchange splittings of the narrow Cu 3d bands open an insulating gap, and that the strong d-d electron correlations increase the gap substantially. The present results accord with the experimental ones.

We have calculated and compared the electronic structures of both the 1D CuO-chain compound SrCuO2 and the 2D CuO2-plane material CaCuO2, on the basis of the local-spin-density approximation (LSDA) and the on-site Coulomb interaction correction (LSDA+U). The LSDA calculation gives a nonmagnetic and metallic solution as usual for CaCuO2, while it yields an antiferromagnetic (AFM) and insulating one for SrCuO2 due to the decreasing pd hybridization and the subsequent spin polarization with lowering dimensionality. Strongly in favour of orbital and spin polarizations of the Cu 3d states, the U interaction dominates in forming the charge transfer insulating character of both of the AFM cuprates. Some of the differences between the electronic structures can be qualitatively accounted for by the variance of dimensionality.

A new mechanism is proposed to explain the colossal magnetoresistance and related phenomena. Moving electrons accompanied by Jahn-Teller phonon and spin-wave clouds may form composite polarons in ferromagnetic narrow-band manganites. The ground-state and finite-temperature properties of such composite polarons are studied in the present paper. By using a variational method, it is shown that the energy of the system at zero temperature decreases with the formation of composite polaron; the energy spectrum and effective mass of the composite polaron at finite temperature is found to be strongly renormalized by the temperature and the magnetic field. It is suggested that the composite polaron contribute significantly to the transport and the thermodynamic properties in ferromagnetic narrow-band metallic manganese oxides., Comment: Latex, no figure

In this reply our previous calculations are checked. Small variances of the calculated results do not change our conclusions.

A full-potential band calculation for La2CuO4 is performed within the local-spin-density approximation. It is shown that the strongly orbital-dependent exchange splittings due to the anisotropic exchange potential induce an antiferromagnetic and insulating solution improved upon the previous nonmagnetic and metallic one.

The electronic structure of NiO has been calculated within the self-consistent local spin density approximation(LSDA) as well as with on-site Coulomb interaction(LSDA+U) method. Considering NiO as a typical ionic crystal, the linear muffin-tin orbitals with the ionic sphere approximation method is used. The effect of non-spherical crystalline field is taken into account precisely. The obtained energy-dispersion bands are in agreement with the recent angle-resolved-photoemission spectra.

Spin transfer nano-oscillators (STNOs) are nanoscale devices which are promising candidates for on-chip microwave signal sources. For application purposes, they are expected to be nano-sized, to have broad working frequency, narrow spectral linewidth, high output power and low power consumption. In this paper, we demonstrate by micromagnetic simulation that magnetic skyrmions, topologically stable nanoscale magnetization configurations, can be excited into oscillation by a spin-polarized current. Thus, we propose a new kind of STNO using magnetic skyrmions. It is found that the working frequency of this oscillator can range from nearly 0 Hz to gigahertz. The linewidth can be smaller than 1 MHz. Furthermore, this device can work at a current density magnitude as small as 108 A m−2, and it is also expected to improve the output power. Our studies may contribute to the development of skyrmion-based microwave generators.

Transverse domain wall motion in strips with a series of nanobars placed perpendicularly on either side has been investigated systematically by micromagnetic simulation. Domain wall motion in strips is driven by electric current owing to the spin transfer torque effect. In a strip in contact with nanobars, a domain wall can withstand a high current density (above A/cm2) to maintain structural stability, but the domain wall velocity cannot be increased markedly. Domain wall motion in strips not in contact with nanobars can reach a higher speed under a relatively low current density. To examine the effects of nanobars on domain wall motion, the DW depinning energy and the Walker limit uw at different parameters are discussed systematically.

To evaluate the different effects of Mg-6Zn alloy and Ti-3Al-2.5V alloy implants in intestinal tract healing, we compared these two different alloys with respect to their effect on a rat's intestinal tract, using serum magnesium, radiology, pathology and immunohistochemistry in vivo. It was found using the scanning electron microscope that the Mg-6Zn alloy began to degrade during the first week and that the Ti-3Al-2.5V alloy was non-degradable throughout the process. The Mg-6Zn alloy did not have an impact on serum magnesium. Superior to the Ti-3Al-2.5V alloy, the Mg-6Zn alloy enhanced the expression of transforming growth factor-β1 in healing tissue, and promoted the expression of both the vascular endothelial growth factor and the basic fibroblast growth factor, which helped angiogenesis and healing. The Mg-6Zn alloy reduced the expression of the tumor necrosis factor (TNF-α) at different stages and decreased inflammatory response, which may have been related to the zinc inhibiting TNF-α. In general, the Mg-6Zn alloy performed better than Ti-3Al-2.5V at promoting healing and reducing inflammation. The Mg-6Zn alloy may be a promising candidate for use in the pins of circular staplers for gastrointestinal reconstruction in medicine.

Y0.75−xGdxAl0.10BO3:Eu3+0.10, 0.05R3+ (R = Sc, Bi) (0.00 ≤ x ≤ 0.45) powder samples are prepared by solid-state reaction and their luminescence properties are investigated. With the replacement of Y3+ ions by Sc3+ (or Bi3+) and Gd3+ ions in (Y,Al)BO3:Eu, the intensities of emission at 254 and 147 nm are remarkably improved, because Sc3+ ions can absorb UV light and transfer the energy to Eu3+ ions efficiently. Moreover, Gd3+ and Bi3+ ions act as an intermediate "bridge" between the sensitizer and the activator (Eu3+) in energy transfer to produce light in the (Y, Gd)BO3:Bi3+, Eu3+ system more effectively. After doping an appropriate concentration of Gd3+ into Y0.50Gd0.25Al0.10BO3:Eu3+0.01, Bi3+0.05, the emission intensity reaches its maximum, which is nearly 110% compared with the red commercial phosphor (Y,Gd)BO3:Eu and better chromaticity coordinates (0.650, 0.350) are obtained.

The electronic structure of alpha -Fe and V with H and C as impurities is calculated using the embedded-cluster model in the framework of self-consistent local-density theory. The results obtained reveal that charge transfer between the H atom and the host atoms is small, but the magnetic moments of neighbouring Fe atoms are reduced. The results of the total energy calculation show that H in alpha -Fe prefers to occupy the octahedral interstitial site. On the contrary, there is some charge transfer between the C atom and the host atoms. The distance between the C and nearest-neighbour Fe atoms is elongated 23%. The interaction between the H and the C impurities was studied using a set of clusters of Fe10CH in which the atoms were located in five kinds of configuration. The energy of clusters with H on the octahedral interstitial site is lower than that on the tetrahedral interstitial site.