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Nano-ZnO has the characteristics of photocatalytic performance and excellent transparency and conductivity. Because of its many excellent properties, it also occupies a very important position in the types of semiconductor materials. Nano-ZnO film preparation technology has been researched and developed and applied in many fields, but there are few applied researches on the protection of paper artworks. The main content of this article is the study of the application and enhancement effect of nano-ZnO film preparation technology on the protection of paper cultural relics. In this paper, the sol-gel process is selected in the common film preparation process, and the configured sol is dipped and lifted. By comparing the paper covered with nano ZnO film and the paper not covered with nano ZnO film in the anti-aging performance test, anti-ultraviolet aging performance test, aging appearance change and the experimental results of the mechanical performance test of the application effect of different papers, the results are investigated. The application and enhancement effect of nano-ZnO film preparation technology in the protection of paper art works. Experimental studies have shown that under the same aging time, the mechanical properties of rice paper covered with nano-Zno film are higher than those of blank rice paper without nano-Zno film. The transverse tensile strength of the paper is increased by 5.88 m/N, an increase of 98%. The vertical tensile strength increased by 3.93 m/N, an increase of about 87%, the vertical folding resistance increased by 16 times, the horizontal folding resistance increased by 15 times, and the vertical tearing strength increased by 4.15 m/N, an increase of about 125%, and the transverse tearing degree is enhanced by 2.21 m/N, which is about 64%. The two kinds of rice paper were subjected to warm-heat aging, and the final results showed that the mechanical properties of the two kinds of rice papers showed a decreasing trend, but the mechanical properties of the rice paper covered by the nano-Zno film decreased at a slower rate, and the final mechanical properties were also lower than that of untreated rice paper. Blank rice paper covered with film is better. The experimental results of ultraviolet light on paper aging show that the nano-Zno film covering the paper will delay the paper aging, and the appearance of the nano-Zno film after ultraviolet light does not change significantly. Under the mechanical performance test of nano Zno film on different types of paper application, the tensile strength, folding resistance and tearing degree of the three papers participating in the experiment have been improved, which shows that the nano Zno film has the advantage of strengthening paper. [ABSTRACT FROM AUTHOR]

Aging behavior occurs in the storage process of paper archives, which accelerates the aging process of the paper. Therefore, it is important for paper archives management to explore the aging behavior of acidified paper (AP) and to delay or prevent its further aging. The aging behavior of the commonly used university archives paper with artificial acidification were studied by measuring pH value, electrical conductivity, mechanical properties and whiteness. The results show that the pH value, conductivity, mechanical properties and whiteness of AP change significantly compared with the non-acidified raw paper (P). After dry-heat aging treatment, the pH value of AP decreased more obviously than P, which shows more obvious aging degradation and further acidification of AP. During the aging process of AP, the molecular and structural degradation are promoted by the presence of acidic substances, which increase the electrical conductivity of the system. The microstructures of the paper are changed by acidification and aging treatment, and more fiber fracture, etching and microscopic holes are found in the surface SEM images. The reductions of the tensile index and whiteness of AP are also more significant because of the degradation acceleration of the acid. [ABSTRACT FROM AUTHOR]

To address the problem that the occurrence of large-scale blackouts in the future may cause the lack of power supply in the area and lead to the loss of power to the important places in it and a significant decrease in the living standard of the residents, this paper researches the reliability of the distribution network with electric vehicle virtual energy storage (EVVES). This paper proposes an aggregation model of EVVES applied to distribution networks, establishes the relevant models of EVVES in a virtual energy storage system (VESS) based on it, and proposes a distribution network reliability evaluation method with EVVES. Firstly, an aggregation model of EVVES is proposed to ensure that islands and important loads in the distribution network do not lose power. Secondly, the relevant models in EVVES based on the aggregation model of EVVES are studied. Finally, a distribution network reliability evaluation method with EVVES is proposed based on the traditional reliability evaluation. The improved IEEE-RBTS Bus6 is adopted as an example for reliability analysis, and the simulation results prove the validity of the model established in the paper and demonstrate that the reliability of the distribution network can be significantly improved with EVVES. [ABSTRACT FROM AUTHOR]

The aging and acidification behavior of paper archives affect their long-term preservation. Therefore, delaying or preventing aging and acidification has become an important topic in the field of paper archives management. the aging and acidification behavior of commercial archival paper were studied by measuring pH value, electrical conductivity, mechanical properties and whiteness in this work. The results show that the aging and acidification phenomena are obvious after dry-heat aging treatment. The molecular degradation of cellulose, hemicellulose, lignin and other components results in the decrease of pH value of the system, which decrease with the increase of the treatment temperature and time. The electrical conductivity of the system increases because of the molecular degradation and structural degradation, and with the increase of the treatment temperature and time, the electrical conductivity increases more significantly. After aging treatment, the paper appears etching and increasing microcosmic pores. With the occurrence of molecular degradation and structural degradation, the tensile index and whiteness of the paper decrease, and with the increase of the treatment temperature and time, the tensile index and whiteness decrease more significantly. [ABSTRACT FROM AUTHOR]

Germanium oxide is an important optical dielectric material with high application value in integrated optical systems. In this paper, the potential energy curves (PECs) of the ground state (Χ1∑+) and three electron low-excited states (a3Σ+, A1Π and B3Π) of GeO molecules (a3Σ+, A1Π and B3Π) were calculated by using the Dunning's related harmonic basis function and large basis group aug-cc-pwCV5Z with diffusion groups. The analytical potential energy function was obtained by fitting the Murrell-Sorbie function (MS) and the least squares method, and the fitting error was very small, indicating that the obtained analytical potential energy function could reproduce the interaction between atoms in GeO molecules. The spectral constants calculated by using the obtained analytical potential energy function are in good agreement with the experimental values, indicating the reliability and accuracy of the obtained analytical potential energy function. [ABSTRACT FROM AUTHOR]

The development of micro-electronic products and the increase in demand for portable devices have driven the research of planar micro-supercapacitors (PMSCs). Flexible PMSCs have the advantages of high energy and power density, stable cycling performance and good flexibility, which makes the flexible PMSCs valuable for the research in the field of wearable electronic devices. In this paper, graphene quantum dots were selected as the electrode material for the flexible devices and PET as the flexible substrate, and the flexible PMSCs with interdigital electrode width to gap ratio of 60 μm/60 μm were prepared using modified liquid-air interface self-assembly, photolithography and oxygen plasma etching. Cyclic voltammetry, galvanostatic charge-discharge, electrochemical impedance spectroscopy and cyclic stability were performed on the devices with the bending angles of 0°, 60°, 90°, 150° and 180°, respectively, using electrochemical workstation. Redox peaks appeared in the CV curves of the devices at the very low scan rates, indicating that redox reaction occurred and pseudocapacitance effect appeared. The area capacitance, energy density and power density of the devices decreased and the charging time was longer than discharging time after the bending angle was increased. After 10,000 cycles, the cyclic stability for the five bending angles was maintained at more than 71%. In short, the larger the bending angles, the greater the impact on some performance of the devices, and when the devices were placed in non-vacuum environment for too long, some performance after bending but better. [ABSTRACT FROM AUTHOR]

Flexible electrode materials refer to materials used as electrodes in electronic devices, which have characteristics such as softness, flexibility, and stretchability, and are suitable for the preparation of various flexible electronic devices. In this study, in order to optimize the problems of poor specific capacity, low conductivity, and instability of conventional flexible electrode materials, the performance and reliability of the flexible electrode materials were improved by hybridizing graphene oxide (GO) and polyaniline (PANI). In this paper, graphene oxide – polyaniline (GO-PANI) flexible electrode materials were prepared and tested for their performance using graphene and polyaniline. In the experiments, a current density of 1 A/g was selected for the constant current charge/discharge test of GO-PANI electrode materials with different graphene contents to evaluate the performance of GO-PANI electrode materials in energy storage. After the experiments, it was proved that the charge/discharge times of GO-PANI electrode materials were 1430s, 1625s, and 1495s when the graphene content was 1%, 3% and 5%, respectively, and the GO-PANI (3%) electrode material had the longest charge/discharge time. Accordingly, it can be concluded that GO-PANI (3%) electrode material had the best energy storage performance, which could realize a stable and efficient charging and discharging process, and could be used as an ideal electrode material in flexible electronic devices. The research in this paper could provide new ideas and solutions for the development of flexible electrode materials and promote the further development and application of flexible electronics technology. [ABSTRACT FROM AUTHOR]

Polymer-based energy storage media are widely used in electrical and electronic applications due to their high power density and excellent charge and discharge efficiency. In this paper, thermoplastic polyurethane elastomer (TPU) organic fillers were doped with polyetherimide (PEI) by the solution blending method to prepare PEI composite films with excellent energy storage properties. The effects of different TPU contents on the dielectric properties, leakage current density, and energy storage performance of the composite films were explored. The results showed that the flexible TPU fillers, which could improve the inter-chain interactions and spatial structure of PEI, reduced the chain spacing of the polymer, effectively hindered the input of charge carriers, and mitigated the electric field distortion, thus improving the insulation and dielectric properties of PEI. When the mass fraction of the added TPU elastomer reaches 0.75%, the energy storage density of the composite film reaches 11.51 J/cm3, which is 2.88 J/cm3 higher than that of the pure polyetherimide, while maintaining a high charge/discharge efficiency (87.32%), and the energy storage performance has been significantly improved under an applied electric field strength of 600 MV/m. The results show that the composite film is more efficient than the pure polyetherimide, and the energy storage performance has been significantly improved. [ABSTRACT FROM AUTHOR]

In this study, a porous silicon anode material was designed to solve the problems of electrode deformation and electrical contact loss caused by volume expansion during the use of silicon anode material. Silicon-aluminum composite powder prepared by high-energy ball milling method, after Al is removed by chemical etching, Si particles show larger specific surface and porosity, and the larger pores provide a certain buffer space for the volume expansion of silicon during lithium intercalation, which can better release stress during the volume expansion, so that it has better cycle performance and higher capacity retention rate. The results showed that the porous Si anode was prepared by ball milling Si-Al powder for 12 h, and the first charge specific capacity was 2912.9 mAh/g at 200 mAh/g current density, and the coulombic efficiency was 83.91%. After 100 cycles at 400 mA/g current density, the capacity retention rate was 34.6% compared with the fourth cycle. This paper provides a new idea for the industrialization of porous silicon. [ABSTRACT FROM AUTHOR]

Growing studies that show that composite materials can improve performance by making up for the defects of ceramic membranes made of a single material. This paper prepared ZrO2/Al2O3 and TiO2/Al2O3 composite coating sols using the sol-gel technique. Ceramic membranes were prepared by dip-coating process and calcined at 350 °C calcination. The physical-chemical properties of membranes were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), N2 adsorption-desorption measurements and scanning electron microscopy (SEM). The permeability and separation performance of membranes were analyzed by doping amount, dye type and pressure difference as reference factors, and the removal rates of chemical oxygen demand (COD) and chroma in the experiment were compared. These results showed that the modified composite membranes had better microstructure, and their retention rates on the dye solutes were significantly enhanced. When the Zr/Al and Ti/Al molar ratio (nZr, nTi) of the composite membrane is 0.5, under the experimental conditions of 0.2 MPa pressure difference and 30 min filtration time, the membrane rejection rates of the four 50 mg/L dyes reached more than 80%, which was much higher than that of the Al2O3 membrane of 57.9%. At the same time, the removal rates of COD and chroma were also greatly improved. The results revealed that the use of composite materials would be required to further explore their potential to improve the performance of ceramic membranes. [ABSTRACT FROM AUTHOR]