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This study proposes a novel approach for contactless conductivity measurement of nonmagnetic metal sheets for a production line. The system uses a self-resonant eddy-current (EC) sensor as the conductivity probe, of which the sensitivity is enhanced by minimizing the parasitic resistance in the resonant circuit. The output responses at various liftoff distances are nonlinear curves unique to the sample’s conductivity. The quaternary polynomial regression is utilized to establish the analytic approximation function to depict the correlation between the phase and the logarithmic magnitude for standard samples. The phase–magnitude relationships are generally monotonic and useful for conductivity conversion using the standard data. The polynomial interpolation is employed to establish the phase–conductivity relations based on the standard samples. The self-developed computer software can instantaneously convert the probe output into the conductivity of the metallic material under test. The experimental findings point to the feasibility of the suggested method that can perform conductivity measurement with a relative error of less than 3% at a liftoff distance of less than 1 mm, indicating the practicability of the proposed technique in conductivity mapping for nonferrous metals.

Introducing magnetism to two-dimensional topological insulators is a central issue in the pursuit of magnetic topological materials in low dimensionality. By means of low-temperature growth at 80 K, we succeeded in fabricating a monolayer stanene on Co/Cu(111) and resolving ferromagnetic spin contrast by field-dependent spin-polarized scanning tunneling microscopy (SP-STM). Increases of both remanence to saturation magnetization ratio (Mr/Ms) and coercive field (Hc) due to an enhanced perpendicular magnetic anisotropy (PMA) are further identified by out-of-plane magneto-optical Kerr effect (MOKE). In addition to ultraflat stanene fully relaxed on bilayer Co/Cu(111) from density functional theory (DFT), characteristic topological properties including an in-plane s–p band inversion and a spin–orbit coupling (SOC) induced gap about 0.25 eV at the Γ̅ point have also been verified in the Sn-projected band structure. Interfacial coupling of single-atomic-layer stanene with ferromagnetic Co biatomic layers allows topological band features to coexist with ferromagnetism, facilitating a conceptual design of atomically thin magnetic topological heterostructures.

Esterification reaction of lactic acid with butanol to produce butyl lactate and its optimal conditions were investigated. Cyclohexane was used as entrainer to remove water to promote reaction yield. Catalyst of NaHSO4 was also used to increase reaction rate. Reaction parameters of butanol/lactic acid ratio, cyclohexane/lactic acid ratio, catalyst amount, and reaction time were optimized using Response Surface Methodology (RSM). Results showed that the butanol/lactic acid ratio was the most significant factor for esterification yield while interactions between butanol/lactic acid ratio and cyclohexane/lactic acid ratio, butanol/lactic acid ratio, and reaction time were less significant. The correlation coefficient between predicted values and experiment values was 0.985. The optimal conditions for the experiment are: ethanol/lactic acid ratio 5:1, cyclohexane/lactic acid ratio 1:1, catalyst loading 1.5%, and incubation period 3 hours. The esterification yield reaches 99.8% under these conditions.

The luminescence investigations on the calcinated zinc tungstate nanopowder (ZnWO4 NP) synthesized by microwave-assisted synthesis are presented using photoluminescence (PL) and time-resolved photoluminescence (TRPL) analyses. The X-ray diffraction (XRD) patterns exhibit that the significant wolframite structure of ZnWO4 NP can be detected at calcination temperatures above 300 oC. The 12 K PL and TRPL results demonstrated that the deformation of WO6 octahedra is responsible for the low-energy side of PL spectra and dominate the red-shifted PL spectra with increasing calcination temperatures.

In order to improve the traditional fuzzy comprehensive evaluation model of main factors, the paper used the shortage of the outstanding balance average type instead of traditional fuzzy comprehensive evaluation method in the evaluation process and takes big or small algorithm, this method to avoid maximum membership principle may cause information loss, more objective quantitative determination of water quality class. This paper Liaozhong waterfront city underground water quality testing data as the basis, an improved fuzzy comprehensive evaluation method to evaluate, the result is due to the area of iron and manganese from groundwater seriously overweight cause groundwater quality grade V. Show that the method of water quality evaluation, the result more objective and accurate.

Band gap opening and engineering is one of the high priority goals in the development of graphene electronics. Here, we report on the opening and scaling of band gap in BN doped graphene (BNG) films grown by low-pressure chemical vapor deposition method. High resolution transmission electron microscopy is employed to resolve the graphene and h-BN domain formation in great detail. X-ray photoelectron, micro-Raman, and UV–vis spectroscopy studies revealed a distinct structural and phase evolution in BNG films at low BN concentration. Synchrotron radiation based XAS-XES measurements concluded a gap opening in BNG films, which is also confirmed by field effect transistor measurements. For the first time, a significant band gap as high as 600 meV is observed for low BN concentrations and is attributed to the opening of the π–π* band gap of graphene due to isoelectronic BN doping. As-grown films exhibit structural evolution from homogeneously dispersed small BN clusters to large sized BN domains with embedded diminutive graphene domains. The evolution is described in terms of competitive growth among h-BN and graphene domains with increasing BN concentration. The present results pave way for the development of band gap engineered BN doped graphene-based devices.

Developments in nanotechnology and natural product research toward the search for novel antibacterial agents have drawn the interest of many scientists to the synthesis of silver nanoparticles (AgNPs) from natural product (especially plants) due to its numerous benefits over other methods of synthesis such as been easy, economical, convenient, and environmental friendly. Aside from the aforementioned advantages, the synthesis of AgNPs from medicinal plant has been reported as the best approach of synthesizing AgNPs with great biological activities due to the numerous biomolecules found in plants. Recently, the number of researches toward the improvement of the yield, morphological properties, analytical techniques, and the development of optimal conditions and exact mechanism for synthesizing AgNPs from plants have been increasing tremendously. In this review, we present a comprehensive report on the recent development in the synthesis, optimization conditions, mechanism, and characterization techniques of AgNPs synthesized from plant extracts. Furthermore, a thorough discussion on the recent advances in the application of AgNPs synthesized from plant as therapeutic agent against bacterial infections was made.

We report that antiferromagnet-induced perpendicular magnetic anisotropy (PMA) occurring in magnetic thin films can be effectively controlled by applying ultrathin in-plane magnetic supporting layers with high ferromagnetic ordering temperature through magnetic proximity effects. In a series of epitaxially grown 12-ML Ni/Co/Mn/Co/Cu(001) films, we observed that the PMA of the top 12-ML Ni/Co films and the long-range antiferromagnetic ordering of Mn film were enhanced concurrently with the establishment of ferromagnetic ordering of the bottom Co film. This clearly proves the underlying mechanism of magnetic proximity effects, and offers another degree of freedom for the control of perpendicular-based magnetic logical devices.

Nanosized ultrathin magnetic films were prepared by controlling the deposition of Fe onto an oxidized NiAl(001) surface with an alumina nanostructure on it. Because the ultrathin ferromagnetic Fe films on the bare NiAl(001) surface are separated by paramagnetic Fe nanoparticles on the alumina stripes, as determined by scanning electron microscopy with spin analysis, they form rectangular domains with sizes ranging from tens of nanometer to larger than a micrometer. Magnetic domain patterning can thus be achieved by controlling the Fe coverage and nanostructured template.

Antiferromagnetic-ferromagnetic exchange coupling is known for its pinning effect on the magnetic hard layer through coercivity enhancement or exchange bias. This study reports its effect on controlling perpendicular magnetization in the soft magnetic regime. In a series of Ni78Fe22(Py)/Mn bilayers, we demonstrate that the magnetization, coercivity, and thermal stability of perpendicular anisotropy can be controlled by varying the thicknesses of the Py and Mn layers, based on the competition between the in-plane anisotropy of the Py layer and the out-of-plane-oriented Py-Mn exchange coupling. This offers a new possibility for the design of magnetic free layers in perpendicular-based magnetic logical devices.