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Improving the magneto-optical saturation signal of materials is a crucial area of research in the field of magneto-optical effect. Au@Pt nanohybrids (Au@Pt NHs) with surface plasmon resonance and spin-orbit coupling effects were fabricated using a microfluidic technique in this investigation. The Au@Pt NHs were directly dripped onto the CoFeB/W film as a deposition layer, and its dual-mode resonance was applied to increase the longitudinal saturated magneto-optical Kerr angle of the CoFeB/W film by 4.4 times. The innovative concept of using a dual-mode resonance in this paper provides a new idea for the further search of materials that have large magneto-optical coefficients.

Macroscopic magnetic properties of magnets strongly depend on the magnetization process and the microstructure of the magnets. Complex materials such as hard-soft exchange-coupled magnets or just real technical materials with impurities and inhomogeneities exhibit complex magnetization behavior. Here we investigate the effects of size, volume fraction, and surroundings of inhomogeneities on the magnetic properties of an inhomogeneous magnetic material via micromagnetic simulations. The underlying magnetization reversal and coercivity mechanisms are revealed. Three different demagnetization characteristics corresponding to the exchange coupling phase, semi-coupled phase, and decoupled phase are found, depending on the size of inhomogeneities. In addition, the increase in the size of inhomogeneities leads to a transition of the coercivity mechanism from nucleation to pinning. This work could be useful for optimizing the magnetic properties of both exchange-coupled nanomagnets and inhomogeneous single-phase magnets.

In this paper, the discoloration of the solder after the vacuum sintering of the power chip is analyzed. The morphology and composition of the discoloration area were characterized and analyzed by the metallographic microscope, SEM, EDS and XPS, and the discoloration mechanism was studied. The analysis results show that the main components of the color-changing solder are C, O, Pb, Sn, Ni, Ag, and Au, which are the normal components of the solder after vacuum sintering. The reason for color-changing is the oxidation of the Sn element, and the different thickness of oxide shows different colors. The discoloration solder was treated with formic acid, and the solder returned to bright silver-white. The test further confirmed that the discoloration was caused by metal oxidation. The problem of solder discoloration is solved by optimizing the process to reduce the sintering time and vacuum defoaming time.

We present an efficient strategy, that is the co-substitution of Fe3+ and Ta5+ ions with large radius for Ti4+ ion, to enhance energy storage performance of Ba2Bi4Ti5O18 film. For the films co-doped with Fe3+ and Ta5+ ions, the maximum polarization under the same external electric field is improved because the radius of Fe3+ and Ta5+ ions is larger than that of Ti4+ ion. Moreover, due to the composition and chemical disorder, the relaxor properties are also slightly improved, which can not be achieved by the film doped with Fe3+ ions only. What is more, for the films doped with Fe3+ ion only, the leakage current density increases greatly due to the charge imbalance, resulting in a significant decrease in breakdown strength. It is worth mentioning that the breakdown strength of Fe3+ and Ta5+ ions co-doped film does not decrease due to the charge balance. Another important point is the recoverable energy storage density of the films co-doped with Fe3+ and Ta5+ ions has been greatly improved based on the fact that the maximum external electric field does not decrease and the maximum polarization under the same external electric field increases. On top of that, the hysteresis of the polarization has also been improved. Finally, the co-doped films with Fe3+ and Ta5+ ions have good frequency and temperature stability.

With the development of type II high temperature superconducting (HTS) ReBCO tape, it has been widely used in high field magnets. Conductor on round core (CORC) cable is highly flexible and fully isotropic, making it one of the most important types of HTS cables. In the condition of high field and current, the electromagnetic and mechanical behaviors of CORC cable under screening current effect are not clear. In this paper, the behaviors of CORC cable under high field and current are studied for the first time by combining electromagnetic and mechanical simulation. A three-dimensional shell model and a three-dimensional solid element model of single-layer CORC cable are established by finite element software to study the electromagnetic and mechanical properties of CORC cable, respectively. Compared with the case without taking screening current into account, two current loops are induced within a pitch of the CORC cable due to the screening current, and the magnetic field homogeneity is significantly reduced. Meanwhile, two pairs of shear force are generated at the current loops meeting zones, it results in a certain degree of stress concentration. Fortunately, because the copper core provides stable mechanical support for the HTS tape, there is no significant difference of the maximum stress between two cases with and without screening current in the CORC cable.

Hydroxyapatite nanoparticles (HAP) have been widely used in various fields because of their natural biological origin and functional properties. The emerging evidence on their toxicities has attracted research interest. HAP-induced vascular smooth muscle cell (VSMC) damage is a key step in vascular calcification (VC), particularly in patients with chronic kidney disease. However, the injury effects and mechanism of action of HAP on VSMCs have not been extensively investigated. This study comprehensively characterized commercially available HAP and investigated its adverse biological effects in cultured A7R5 cells. In vitro experiments revealed that internalized HAP was localized in lysosomes, followed by the release of Ca2+ owing to the low pH microenvironment. Upon Ca2+ homeostasis, Ca2+ enters the mitochondria, leading to the simultaneous generation of reactive oxygen species (ROS). ROS subsequently attack mitochondrial transmembrane potentials, promote mitochondrial ROS production, and oxidize mitochondrial DNA (Ox-mtDNA). Mitochondrial permeability-transition pores open, followed by the release of more Ox-mtDNA from the mitochondria into the cytosol due to the redox imbalance. This activates NLRP3/caspase-1/gasdermin D-dependent pyroptosis and finally excretes inflammatory factors to induce VC; an antioxidant could rescue this process. It has been suggested that HAP could induce an imbalance in intracellular Ca2+ homeostasis in A7R5 cells, followed by the promotion of mitochondrial dysfunction and cell pyroptosis, finally enhancing VC. To detect the in vivo toxicity of HAP, mice were treated with Cy7-labelled HAP NPs for 24 h. In vivo results also demonstrated that HAP accumulated in the kidneys, accompined with increased Ca concentration, upregulated oxidative stress-related factor and kidney damage. Overall, our research elucidates the mechanism of calcium homeostasis and redox imbalance, providing insights into the prevention of HAP-induced cell death.

Distribution network grounding fault testing technology relies on a single criterion, which has a positioning blind area, resulting in large ranging error. In this paper, a grounding fault test technology for distribution network based on zero sequence power direction determination is proposed. The direction from the power supply side to the load terminal is specified as the positive direction of the network, the fault equivalent zero sequence current is modeled, and the high-frequency component of transient zero sequence current containing main fault characteristics is extracted. The fault line is determined based on the zero sequence power direction. For the fault line, the zero sequence power is less than zero, and the absolute value is much greater than the normal line, and the line selection device can select the line normally. The grounding fault test model of distribution network is established, and the fault current difference of each measuring point is calculated. When the difference is the smallest, it is identified as the fault location. The average ranging error of the test technology based on zero sequence power direction determination is 50.68m, which is 20.24m and 23.55m lower than that based on wavelet analysis and EMD. Therefore, it can accurately determine the fault line and has strong positioning advantages.

With the higher share of renewable energy, the flexibility of the power system needs to be improved. In recent years, the loads on the demand side can provide flexibility with the development of demand response technology. Thermostatically controlled loads (TCLs), as a kind of large-scale flexible load, have been a significant demand response resource. In this paper, a demand response strategy for TCLs considering consumer utility function is proposed. Firstly, a utility function is modeled to estimate the utility of TCLs. Then a model for estimating the potential of TCLs is built. On this foundation, the power system operators (PSOs) sort TCLs by consumer utility. TCLs with lower consumer utility will be called first. The study case adopts realistic data of an eastern city in China, which verifies the effectiveness of the proposed strategy.

With the continuous development of social economy, the application market of electric motors has become more and more broad. Based on the principle of modular design, this paper designs the hardware circuit system of the matrix converter, and completes the parameter calculation of the input LC filter. The modulation algorithm needs to determine the sector and position angle of the input three-phase voltage. The DC speed regulation system powered by the conversion AC-DC power conversion technology is compared with the Buck circuit power supply system. Practice shows that the system has good static and dynamic indicators and load robustness.

The construction industry is considered to be one of the largest contributors to greenhouse gas (GHG) emissions globally, accounting for around one-third of the total in world. Carbon emissions generated from heavy equipment on dam construction site are normally estimated without distinguishing the working modes, which may not represent on-site situations. Thus, this paper aims to evaluate carbon emissions of heavy equipment on dam construction sites, by establishing a methodology and applying the Discrete Event Simulation (DES) model. The case study demonstrates that DES model is validated to simulate the working models accurately, and the idling time of heavy equipment can influence carbon emissions a lot. It is suggested that dam project stakeholders should develop appropriate equipment management plans by using DES and improve the working efficiency, realizing the carbon reduction.

It is difficult to monitor the surface deformation along the high-speed railway for the complexity of the surface texture in extensive region. In this paper, based on sentinel-1A /B data, the surface deformation along the high-speed railway from Fuyu to Dehui was tried to evaluate using time-series PS-InSAR method. The results indicate that the surface deformation is not dangerous for the safe operation of the railway. Moreover, the surface depression near Dehuixi station is potentially dangerous for the safety of the railway. Finally, the cause of the surface deformation along the railway is mainly attributed to the human activity and the seasonal subgrade frost heave in the seasonal frozen soil.

With the increasing maturity of WebGL technology as well as the development and construction of the 3D geographic information system, 3D geographic information sharing service has become the trend of future development. There are numerous three-dimensional data sources of the power grid and many applications across departments and systems, but the three-dimensional geographic information service based on unified standards is still rarely seen. The paper studies and discusses the selection of 3D service standards and the implementation technology of 3D geographic information service for the power grid.

This study reports a facile fabrication of black TiO2−x /NiFe2O4 (Ti3+ self-doped titania coupled with nickel ferrite), an efficient sonocatalyst for ibuprofen (IBP) mitigation. Compared with TiO2−x or NiFe2O4, TiO2−x /NiFe2O4 heterojunction displayed higher sonocatalytic activity, and their immobilization onto diatomaceous earth further enhanced mitigation efficiency due to the synergy between adsorption and sonocatalysis. About 96.7% of 10 mg l−1 IBP was removed in 100 min using 0.7 g l−1 catalyst at pH = 6, with the ultrasonic power of 144 W and frequency of 60 KHz. Quenching experiment results demonstrated the roles of reactive species. The intermediates during IBP sono-oxidation were determined by HPLC-MS method, and the acute toxicity was evaluated. Furthermore, the reaction mechanism was proposed. The sonocatalyst revealed excellent reusability, suggesting itself promising for wastewater treatment.

We report a distinctive way for designing lead-free films with high energy storage performance. By inserting different single perovskite cells into Bi4Ti3O12, P–E hysteresis loops present larger maximum polarization, higher breakdown strength and smaller slim-shaped area. We prepared 0.15Bi7Fe3Ti3O21-0.5Bi4Sr3Ti6O21-0.35Bi4Ba3Ti6O21 solid solution ferroelectric films employing the sol-gel method, and obtained high energy storage density of 132.5 J/cm3 and efficiency of 78.6% while maintaining large maximum polarization of 112.3 μC/cm2 and a high breakdown electric field of 3700 kV/cm. Moreover, the energy storage density and efficiency exhibit stability over the temperature range from 20 °C to 125 °C, and anti-fatigue stability maintains up to 108 cycles. The films with a simple preparation method and high energy storage performance are likely to become candidates for high-performance energy storage materials.

Distinctive superconducting behaviors between bulk and monolayer FeSe make it challenging to obtain a unified picture of all FeSe-based superconductors. We investigate the ultrafast quasiparticle (QP) dynamics of an intercalated superconductor (Li1 – x Fe x )OHFe1 – y Se, which is a bulk crystal but shares a similar electronic structure with single-layer FeSe on SrTiO3. We obtain the electron-phonon coupling (EPC) constant λ A 1g (0.22 ± 0.04), which well bridges that of bulk FeSe crystal and single-layer FeSe on SrTiO3. Significantly, we find that such a positive correlation between λ A 1g and superconducting T c holds among all known FeSe-based superconductors, even in line with reported FeAs-based superconductors. Our observation indicates possible universal role of EPC in the superconductivity of all known categories of iron-based superconductors, which is a critical step towards achieving a unified superconducting mechanism for all iron-based superconductors.

Timely accurate traffic prediction is important in the Intelligent Traffic System (ITS). It has time-varying traffic patterns and the complicated spatial dependencies on traffic network topology which makes the prediction challenging. In this paper, we propose a novel deep learning framework—Graph Wavelet Long Short-Term Memory Neural Network (GWNN-LSTM) to capture the spatial and temporal dependence simultaneously. Moreover, Graph Wavelet Neural Network (GWNN) is utilized for spatial correlations and Long Short-Term Memory Neural Network (LSTM) is used to capture the dynamic temporal correlations in traffic time series data. Experiments on real-world datasets from loop detectors in the highway of Los Angeles County (METR-LA) demonstrate that the proposed GWNN-LSTM model outperforms the state-of-the-art baselines.

With the rapid development of society, the study pressure of teenagers and the work pressure of adults are more and more heavy, which also leads to the disharmony of parent-child relationship. Therefore, this paper uses computer to set up the software of improving parent-child relationship, which mainly includes the examples of improving teenagers. Through computer-aided technology, this paper tests the effect of improving the parent-child relationship of teenagers. Through the test results, we can know that computer-aided technology can guide the psychological quality of teenagers, which will greatly alleviate the parent-child relationship of teenagers.

Firstly, the eutrophication of five monitoring points in Shenzhen Bay was analyzed by using the nutritional status quality index method, and the eutrophication of the entire Shenzhen Bay was analyzed by the results of the eutrophication model simulation. The results showed that the maximum of the nutritional status quality index(NQI) in the dry season was 22, the minimum was 3;the maximum NQI in the rainy season was 23, the minimum was 4, and when NQI is greater than 3, the water is eutrophication level, so whether it was the dry season or the rainy season, Shenzhen Bay is basically eutrophic, and the eutrophication of the Shenzhen Bay in the rainy season is more serious than that in the dry season. Regardless of the dry season or the rainy season, the NQI of the Shenzhen Bay outer area is basically around 5, while the NQI of the interior area is basically larger than that of the outer area. The degree of eutrophication is more serious than that of the outer area;the maximum NQI is 22 in the high tide during the dry season, and the maximum NQI is 23 in the rainy season;the maximum NQI is 21 in the ebb during the dry season, and the maximum NQI in the rainy season is 22, so the eutrophication of Shenzhen Bay is more serious than the ebb when the high tide.

This paper studies design of an access control system based on face recognition for the major purpose of programming face recognition and access systems for embedded equipment. The access control system studied in this paper has functions regarding security, access control, personnel management, travel logs and time management. In this paper, face recognition algorithms are theoretically analyzed and derived. Based on face recognition algorithms, access control systems, particularly including face recognition algorithms, image processing and software, are designed and realized. Overall systematic debugging practices prove that aforementioned algorithms and software designs are correct and effective.

Falling happens when people’s body (excluding feet) unexpectedly touches the ground, which causes serious injuries for old people. Therefore, it is of great significance to assessing old people’s balance characteristics and help them prevent form falling. Based on this, we constructed a feature extraction model and obtained 25 factors that have the greatest influence on body balance by our model. We found that the most influential parts mainly distribute on people’s trunk, left arm, right foot and head, which can be applied in further study of falling prevention and balance supervision.

Environmental degradation is becoming a worldwide problem. However, traditional economic theory often disregards the value of environment in decision making, and the development of land use project usually ignore their damage on the land. As a result, a model needs to be proposed to calculate the cost of environment. We construct an environmental cost evaluation index system for land development projects, in order to calculate the cost of land resources loss. The land resources loss is caused by the destruction of the original land, we analyse it from the value that the land has, including land products value and ecological value. The project pollution cost is resulted from the various pollution that the projects produce after construction, we calculate the pollution treatment cost to estimate the pollution. Moreover, our model can be adjusted to the change of time easily, as we use many constants, such as prices of products and unit grain yield.

In this paper, a conversion platform based on UG CAM and HyperMILL is proposed combining the advantages of both. Complicated features can be programmed with 5-axis machining in HyperMILL, then transformed into tool path files that can be recognized and processed by UG CAM through the platform. Relevant tool information can also be obtained and output during the conversion process for unified management. A case study is presented to validate the proposed methodology and platform.

With the increasing popularity of the network information age, "big data" emerging at the historic moment, has become the hottest IT industry vocabulary. In this context, the application of big data technology plays an important role in the construction of campus knowledge payment platform. Therefore, this paper is dedicated to studying the technical support for the construction of campus knowledge payment platform and the influence of big data on the platform construction, so as to promote the platform technology upgrade and optimize the platform management.

Nitrogen-doped carbon materials with controllable morphologies were prepared via a soft template method using chitosan as the carbon and nitrogen source and F127 or ionic liquid as the template. The performance of the materials as electrodes and adsorbents for carbon dioxide removal were evaluated. Carbon spheres (CSs) with developed micropore structures were obtained without a template, whereas a tubular structure (CSF) containing mesopores with long-range order was obtained using F127. Layered carbon (CSI) containing micro-/mesopores with short- and long-range order was obtained using an ionic liquid. The samples exhibited graphite-like structure and the soft template increased the graphitization degree. Nitrogen existed mainly in the form of pyridine and pyridone groups in CSs and CSF and as pyridine, pyridone, and quaternary groups in CSI. The specific capacitances of CSs, CSF, and CSI were 144, 161, and 178 F g-1, respectively, at a current density of 1.0 A g-1 in 1 M sulfuric acid. The carbon dioxide adsorption capacities of CSs, CSF, and CSI were 142, 73, and 115 mg g-1, respectively; CSs displayed the highest value because of its developed micro- and ultramicroporous structure. Our results indicated that these carbon materials with various morphologies can be used as both electrodes and adsorbents.

The introduction of Keggin-type polyoxometalate (POM) K4SiW12O40 into the solvothermal synthesis system of Cu3SnS4 (CTS) led to the formation of a new CTS-POM particle. The structure and composition were characterized by x-ray diffraction, scanning electronic microscopy and transmission electron microscopy. The results revealed that the CTS-POM particles exhibit multiporous microsphere morphology, which was first observed in CTS materials. A possible growing mechanism was proposed based on POM concentration-dependent growth study of the microspheres. The photodegradation of RhB and H2 production under UV–vis irradiation was done to evaluate the photocatalytic activities of the samples. The results indicated that the as-synthesized CTS-POM exhibited enhanced photodegration of RhB and photocatalytic H2 generation compared to pure CTS particles, and the content of loaded POM has an important impact on the catalytic activity of CTS-POM. The 5% POM-loaded CTS microspheres reached the best photocatalytic activity in H2 production. Meanwhile, increased stability of photocatalytic activity of CTS-POM was also observed.

Carbon-based composite materials with tunable, ordered mesoporous structures were prepared via the hydrothermal carbonization/soft-template method, with nickel nitrate as the doping source, straw as the carbon source, and F127 as the soft template. By adjusting the additive amounts of Ni and F127, the mesoporous structure was controllable, and results were obtained that varied from an irregular stripe-like hexagonal, a regular stripe-like hexagonal, mixed hexagonal and cubic, to cubic. With a specific surface area in the range of 339-963 m2 g-1, the percentage of mesoporous structures increased from 39.6% to 58.3%. Ni doped into the carbon skeletons existed in the form of metallic Ni and nickel oxide. Increased amounts of nickel nitrate for doping as well as F127 is beneficial for the generation of metallic Ni during the preparation process. The average particle diameter of Ni decreased when the Ni-doped content was increased, and all the average particle sizes were less than 10 nm after F127 was added. The Nim/CSFn catalyst demonstrated high catalytic activity when used for the hydrogenation reaction of p-nitrophenol (PNP) to p-aminophenol (PAP). The conversion of PNP reached 98.79%, and the selectivity for PAP reached 89.6% for Ni2.0/CSF1.5, with a corresponding apparent rate constant of 1.56 × 10-3 S-1, apparent activation energy of 41.86 kJ mol-1, and with the added benefit that the catalyst could be separated and recycled by applying an external magnetic field.

A new sandwich-type transition metal complex based on tungstobismuthates and 1-methylimidazole ligands Na7(mim)2[{Na(H2O)2}3{CoII(mim)}3(BiIIIWVI 9O33)2]9H2O (1) (mim = 1-methylimidazole) has been successfully isolated in aqueous solution. The composition and structure were established by the single crystal X-ray diffraction analysis, elemental analysis, IR spectroscopy. Single-crystal X-ray diffraction and TG analyses indicate that compound 1 consists of two tri-vacant [ α -B-BiIIIWVI 9O33]9- units linked through three cobalt ions. All the CoII ions were sandwiched in the middle and bonded with terminal oxo atoms from [ α -B-BiIIIWVI 9O33]9- units as well as 1-methylimidazoles. Photocatalytic experiment indicates that compound 1 exhibit good catalytic activities for photodegradation of RhB under UV irradiation.

In recent years, pollution accidents caused by gas station leakage has occurred worldwide which can be persistent in groundwater. Numerous studies have demonstrated that the contaminated groundwater is threatening the ecological environment and human health. In this article, current status and sources of groundwater pollution by gas station are analyzed, and experience of how to prevent groundwater pollution from gas stations are summarized. It is demonstrated that installation of secondary containment measures for the oil storage of the oil tank system, such as installation of double-layer oil tanks or construction of impermeable ponds, is a preferable method to prevent gas stations from groundwater pollution. Regarding to the problems of groundwater pollution caused by gas station, it is proposed that it is urgent to investigate the leakage status of gas station. Relevant precise implementation regulations shall be issued and carried out, and supervision management of gas stations would need to be strengthened. Then single-layer steel oil tanks shall be replaced by double-layer tanks, and the impermeable ponds should be constructed according to the risk ranking. From the control methodology, the groundwater environment monitoring systems, supervision level, laws and regulations as well as pollution remediation should also be carried out and strengthened.

With the development of industry, oceanic oil production is one of the most important energy resources. Normally, offshore platform, located in the hostile environment, is easily subjected to unstable environmental loading, such as wind, wave, ice, and earthquake, and it becomes a critical problem to ensure the stability of offshore platform for safely engineering operations. In recent years, tuned-mass damper (TMD) technology has been adopted to reduce vibrations from wind and earthquake influences. Due to the complexity of earthquake excitations, most of researchers were focused on controlling response of structures under wind loads; however, less attention has been put on controlling earthquake response. Therefore, this study concentrates on the seismic reduction of offshore platform by application of a TMD system, and a comprehensively experimental study was processed to validate its effectiveness exposed to different earthquake. A 4-column offshore platform was built according to the actual size of approximately 1:200 ratios, and a TMD system was prepared for the experiment. By the different performance analyses, experimental results indicated that the proposed TMD system can effectively suppress the earthquake stimulus and keep the stability of offshore platform.

We present our extensive research into magnetic anisotropy. We tuned the terrace width of Si(111) substrate by a novel method: varying the direction of heating current and consequently manipulating the magnetic anisotropy of magnetic structures on the stepped substrate by decorating its atomic steps. Laser-induced ultrafast demagnetization of a CoFeB/MgO/CoFeB magnetic tunneling junction was explored by the time-resolved magneto-optical Kerr effect (TR-MOKE) for both the parallel state (P state) and the antiparallel state (AP state) of the magnetizations between two magnetic layers. It was observed that the demagnetization time is shorter and the magnitude of demagnetization is larger in the AP state than those in the P state. These behaviors are attributed to the ultrafast spin transfer between two CoFeB layers via the tunneling of hot electrons through the MgO barrier. Our observation indicates that ultrafast demagnetization can be engineered by the hot electron tunneling current. This opens the door to manipulate the ultrafast spin current in magnetic tunneling junctions. Furthermore, an all-optical TR-MOKE technique provides the flexibility for exploring the nonlinear magnetization dynamics in ferromagnetic materials, especially with metallic materials.

The influences of Niobium doping on the glass-forming ability (GFA) and magnetization properties of Nd–Fe–B–Nb alloys were investigated. It is found that the GFA of Nd–Fe–B–Nb alloys are improved by the Nb addition. It is also revealed that the GFA of the samples increases with the Nb content. Rapidly solidified Nd4.5Fe77− x Nb x B18.5 (x = 0, 0.25, 0.5, 0.75, 1) nanocomposite strip flakes were successfully prepared by using strip casting technique with a higher production efficiency and a lower cooling rate compared to melt spinning method. The coercivity of nanocomposite Nd–Fe–B–Nb alloy strip flakes can be dramatically enhanced by 0.5 at. % Nb addition, attributing to grain refinement. The best magnetic properties with H c j = 278.9 kA/m, (BH)max = 41.06 kJ/m3 have been obtained in Nd4.5Fe76.5Nb0.5B18.5 nanocomposite strip flake, which can be used for bonded magnets. The recoil loss of Nd4.5Fe76.5Nb0.5B18.5 alloy is also reduced by the Nb addition.

Copolymerization of styrene (St) and 1-vinyl-3-ethylimidazolium bromide (VEIB), novel poly(St-co-VEIB) microspheres were generated. Owing to the presence of imidazolium groups, such microspheres having an average diameter of 125 nm, behave electropositively when dispersed in aqueous solution. Furthermore, due to the presence of imidazolium groups, having a capacity of ion-exchange and weak reducibility on the surface of the PS microspheres, [Fe(CN)₆]³⁻ was absorbed on the surface of poly(St-co-VEIB) microspheres, and simultaneously, Fe³⁺ was reduced to Fe²⁺. Thus, in situ growth of Prussian blue (PB) nanoparticles could occur on the surface of poly(St-co-VEIB) microspheres without the addition of any other reducing agent. This methodology, utilizing the ion-exchange and weak reducibility properties of the imidazolium groups on the surface of micro-/nanostructures is a novel general method for assembling hierarchical nanostructured materials. Finally, the electrochemical property of the strawberry-like PS/PB composite microspheres was also investigated by applying a glassy carbon electrode. A good repeatability of the cyclic voltammetry responses, having a good linearity and sensitivity, for the electrocatalytic reduction of H₂O₂ was obtained.

Localized optical Airy—Bessel configuration wave packets were first generated on the basis of a grating-telescope combination [Nat. Photon. 4(2010) 103]. By studying the spatially induced group velocity dispersion effect of ultrashort pulsed Bessel beams during propagation, we find the universal physical foundation of generating Airy—Bessel wave packets (ABWs) in free space. The research results are expected to open up more common channels for generating stable linear localized ABWs.

A color evaluation approach for computer-generated color rainbow holography (CGCRH) is presented. Firstly, the relationship between color quantities of a computer display and a color computer-generated holography (CCGH) colorimetric system is discussed based on color matching theory. An isochromatic transfer relationship of color quantity and amplitude of object light field is proposed. Secondly, the color reproduction mechanism and factors leading to the color difference between the color object and the holographic image that is reconstructed by CGCRH are analyzed in detail. A quantitative color calculation method for the holographic image reconstructed by CGCRH is given. Finally, general color samples are selected as numerical calculation test targets and the color differences between holographic images and test targets are calculated based on our proposed method.

The diffusion coefficients of several alloying elements (Al, Mo, Co, Ta, Ru, W, Cr, Re) in Ni are directly calculated using the five-frequency model and the first principles density functional theory. The correlation factors provided by the five-frequency model are explicitly calculated. The calculated diffusion coefficients show their excellent agreement with the available experimental data. Both the diffusion pre-factor (D0) and the activation energy (Q) of impurity diffusion are obtained. The diffusion coefficients above 700 K are sorted in the following order: DAl > DCr > DCo > DTa > DMo > DRu > DW > DRe. It is found that there is a positive correlation between the atomic radius of the solute and the jump energy of Ni that results in the rotation of the solute-vacancy pair (E1). The value of E2−E1 (E2 is the solute diffusion energy) and the correlation factor each also show a positive correlation. The larger atoms in the same series have lower diffusion activation energies and faster diffusion coefficients.

The magnetic anisotropy and magnetization reversal of single crystal Fe films with thickness of 45 monolayer (ML) grown on Si(111) have been investigated by ferromagnetic resonance (FMR) and vibrating sample magnetometer (VSM). Owing to the significant modification of the energy surface in remanent state by slight misorientation from (111) plane and a uniaxial magnetic anisotropy, the azimuthal angular dependence of in-plane resonance field shows a six-fold symmetry with a weak uniaxial contribution, while the remanence of hysteresis loops displays a two-fold one. The competition between the first and second magnetocrystalline anisotropies may result in the switching of in-plane easy axis of the system. Combining the FMR and VSM measurements, the magnetization reversal mechanism has also been determined.