In this work, poly(vinylidene fluoride-hexafluoropropylene)/reduced graphene oxide films were prepared by the solution casting method with N,N-dimethylformamide (DMF) and DMF/acetone mixed solvents. The effects of reduced graphene oxide and solvent type on the morphology and crystal structure of the composite films were investigated by using scanning electron microscopy, Fourier-transform infrared spectroscopy, and Raman spectroscopy, respectively. The morphology study showed that the addition of acetone in the film process resulted in the occurrence of tiny pores on the film surfaces. The reduced graphene oxide incorporated into the PVDF-HFP was able to promote the formation of β- phase in the composites. The maximum power of 15.58 µW was obtained from the films using DMF/acetone mixture as solvent.

HfO2 and La-doped HfO2 with 20, 40, 50, and 60 mol% were deposited on silicon wafers by spin-coating technique. The crystallization process was annealed temperature at 600 °C. Then, characterization techniques of XRD, AFM, SEM, Full-field XRF imaging, and XAS were applied to reveal structural morphology, local structure, grain, distribution, etc. This study aims to investigate the effect of doping La into the HfO2 system on surface formation, microstructure, and dielectric properties. According to the results, RMS surface roughness, and grain size increased relative to La concentration levels. These films demonstrated homogeneous, low surface roughness, and crack-free. The XRD confirms the existence of the monoclinic phase in pure HfO2 and the mixture phase of the monoclinic and orthorhombic phases in La-doped HfO2 films. Increasing La concentration caused the structural transformation, the XAS of La L3 -edge indicating that lanthanum remained in the HfO2 system. Dielectric response based on interface-phase polarization was improved with La content from 0 mol% to 60 mol%. Compared with HfO2 film, the dielectric constant of La-doped HfO2 films was increased and dielectric loss was decreased.

The epoxy resin-based nanocomposites have been used to overcome the drawback of epoxy resin such as brittle, low impact resistance, poor stress cracking and poor corrosion resistance in the aggressive environment by incorporating inorganic nanoparticles into the high cross-linked structure of epoxy resin. However, the main problem of these composites is the agglomeration of nanoparticles which influences the worst dispersion in the epoxy matrix and leads to poor properties of the composite. Therefore, this work aims to study the effect of nanoparticle additions, i.e. ZrO2 nanoparticle and SiO2 nanoparticle including waste glass powder (WGP) which is an alternative inorganic filler, on properties of the epoxy resin-based nanocomposite. The particle surface of each filler was also modified with 3-glycidoxypropyltrimethoxysilane (GTPMS) in order to achieve better dispersion in the disk-shaped bulk composites. The chemical property of modified fillers was characterized by Fourier transform infrared spectroscopy (FT-IR). The physical properties, mechanical properties, water absorption and corrosion resistance of all composites are then investigated. The results revealed that the incorporations of ZrO2, SiO2, and WGP with GPTMS surface modification into epoxy resin-based nanocomposite exhibit better performance in mechanical properties, water absorption and corrosion resistance than the unmodified surface of ZrO2, SiO2, and WGP additions. Although, both modified- and unmodified surfaces of fillers for the epoxy resin-based nanocomposites show improvement in all properties compared to the neat epoxy resin but the electrical properties of epoxy resin-based nanocomposites with unmodified fillers and GPTMS-modified fillers do not show a significant effect on any electrical properties.

A composite of bacterial cellulose and titanate nanotubes (BC/TNT) was prepared for use as a stretchable motion sensor in smart and wearable electronics. The composite was characterized using various techniques such as UV-VIS-NIR spectroscopy, SEM, XRD, IR spectroscopy, and thermogravimetric analysis. It was found that the dielectric constant of BC/TNT was up to 2.6 times that of BC with similar loss tangent, indicating improved charge storage. The composite was also constructed into a Kirigami pattern for improved stretchability. With a tensile strain of 0.4%, the change in resistance relative to the original resistance (ΔR/R 0) was found to be 5.7% and 6.9% for BC and BC/TNT, respectively, demonstrating improved sensing performance.

Due to its adaptability in scaling up, a redox flow battery (RFB) is seen to be one of the finest options for large-scale electrical backup systems. As a result, it is feasible to create RFB systems that are both cost and performance effective. Recently, a zinc-manganese RFB that relies on Zn(s)/Zn2+(aq) and Mn2+(aq)/MnO2 redox couples has gained attention since both zinc and manganese are cheap, abundant, and eco-friendly. However, the reversibility of Mn2+(aq)/MnO2 at the positive electrode is limited by the formation of Mn3+ species upon charge/discharge (CD) cycling, resulting in severe capacity fading. Herein, this study examines the use of reducing agents as electrolyte additives to enhance the reversibility of the Mn2+(aq)/MnO2 reaction. Experimental results indicate that sulfuric acid and oxalic acid as additives can significantly improve the reversibility of the Mn2+(aq)/MnO2 reaction and the cycling stability of zinc-manganese RFBs. The acetate-based system demonstrates better reversible reaction than the sulfate-based system having more than 100 CD cycles at a current density of 10 mA/cm2. Coulombic efficiency (CE) is also seen to be higher than 90%. Overall, results lead to increased efficiency and cycling stability for zinc-manganese RFBs.

A wide-gap semiconductor of Yttria (Y2O3) doped with nonmetal elements (B, C, and N) are investigated by using the first-principles method. We mainly discuss the exchange coupling between two dopants and find that the exchange coupling in current cases are sensitive to the B-B, C-C, and N-N distance. Unitary ferromagnetic (FM) and antiferromagnetic (AFM) states have been observed in the two-B-doped and two-N-doped Y2O3 structures, respectively. Surprisingly, as the C-C distance increases, a transformation between FM and AFM has been found, which shows an RKKY-like interaction due to the p-d hybridization between the C dopant and intrinsic Y atoms.

The present work reports the experimental results of studying linear and nonlinear dielectric properties of a ferroelectric nanocomposite from RbNO3 embedded in pores of an Al2O3 matrix. The dielectric relaxation times were determined above and below the phase transition temperature of pure RbNO3 (436 K). It was shown that for RbNO3 incorporated into nanosized pores of the Al2O3 matrix, a decrease in the phase transition temperature and a change in relaxation times were observed.

In actual production, shaft parts are affected by the working environment, and are prone to failures such as wear, deformation, corrosion, etc. If the parts that are scrapped due to service damage can be repaired, it can not only save huge economic and time losses, but also It can also improve the utilization rate of resources, in line with the national sustainable development strategy. In this paper, laser cladding technology is used to strengthen the surface of the laser cladding coating for sewing machine shaft parts, and analyze the microstructure, hardness, friction and wear properties of the cladding layer after laser cladding. It is concluded that the average hardness of the cladding layer is about 740.3HV, which is about 2.9 times that of the substrate; the wear loss of the cladding layer is greatly reduced, which are 34%, 40% and 48% of the substrate, respectively, which are less than half of the wear amount. It can be seen that laser cladding on the surface of shaft parts can improve the surface quality of the parts and prolong the service life of the parts.

The indoor environment simulation and optimization of atrium buildings are a research hotspot in the field of architectural technology. This article presents linear atrium buildings as the research object, introduces DeST simulation technology into thermal environment analysis, and studies the dynamic conditions and typical day time, the atrium itself structure, the structure of the rooms around the atrium and the thermal environment of the atrium space and its adjacent rooms. In the research process, two modes of natural ventilation and air conditioning were considered, and the optimal atrium building structure parameters under different outdoor weather conditions were obtained. The research results show that in natural ventilation mode, the thermal comfort temperature is the best when the atrium’s aspect ratio is 1.71; when using the air-conditioning mode, the air conditioning load is the smallest when the atrium’s aspect ratio is 1.55. In summer, the thermal environment of the linear A-shaped atrium is better than the H-shaped atrium. When the atrium window hole position is about 0.9 ∼ 1.5 m, the thermal environment is comfortable and energy saving.

NiCrAl/20%WC coatings were prepared by laser cladding on 45 steel under different technological parameters. The effects of technological parameters on the microstructure, microstructure, hardness and wear resistance were investigated. The results show that with the increase of the scanning speed, the height, width, depth and dilution rate of the cladding layer gradually decrease, the microstructure becomes smaller and smaller, the hardness gradually increases, and the wear amount decreases first and then increases, and the wear amount is the least when the scanning speed is 600 mm/min. With the increase of laser power, the height, width, depth and dilution rate of cladding layer gradually increase. The hardness gradually decreases; The wear decreases first and then increases, and the wear is the least when the laser power is 1.2 kW.