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Doping and coating are frequently employed for the improvement of the properties of Ni-rich NCM materials. In this work, we prepared stable LiNi0.8Co0.1Mn0.1O2 (NCM811) materials modified with Y2O3 via a wet chemical method. In order to investigate the action mechanism of Y2O3 on NCM811, we analyzed the microstructures using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Also, to study the electrochemical performances, we conducted a charge/discharge test and cyclic voltammetry. Our results show that Y2O3 modified NCM811 materials have good thermal stability, and proper content of Y2O3 can effectively prevent the materials from damaging and significantly improve the electrochemical properties of the materials. Particularly, 1% Y2O3 modified NCM811 material show much better cycling performance than other samples. During cycling at 1.0C, the 1% Y2O3 modified NCM811 shows capacity retention of 90.1% after 100 cycles, which is higher than 69.4% for pristine NMC811. We examined the microstructures of the materials before and after circulation. Using the SEM results, we conclude that structural changes are among the key factors that lead to the degradation of the electrochemical properties of materials.

This work aimed to clarify the influencing factors and mechanism of the moisture re-adsorption characteristics of dried lignite through a combination of experiment and simulation. By using the self...

Relative tool sharpness (RTS) is identified as the ratio of undeformed chip thickness to tool cutting edge radius. This paper studies the effects of RTS on the surface generation mechanism of precision turning of electroless nickel-phosphorus (Ni-P) coating. An R-shaped tungsten carbide (WC) tool was adopted for the face turning experiment. The cutting edge radius was 1.84 μm measured by a laser scanning confocal microscope (LSCM). The chip formation behavior, cutting forces and surface morphology were investigated under different RTS values. Results showed that the chip changes from continuous to discontinuous as RTS decreases from 0.54 to 0.27, indicating the transition of the material removal mechanism. The periodical fluctuations with small amplitudes on the machined surface are associated with the high-frequency tool-tip vibration. The low-frequency fluctuations of the cutting forces are related to the material swelling and recovery. The optimal machined surface roughness was obtained at the RTS of 0.38.

Hepatocellular carcinoma (HCC) is a primary malignancy of the liver and the third leading cause of cancer death worldwide. The incidence of HCC accounts for more than 90% of primary HCC. Like most solid malignancies, the occurrence and development of HCC are closely related to the Warburg effect. The Warburg effect of HCC is mainly manifested as increased glucose uptake by HCC cells, increased glycolysis, restricted mitochondrial oxidative phosphorylation, increased pentose phosphate pathway in HCC cells, and increased glutamine decomposition. As the contribution of glycolysis to the total ATP of tumor cells generally does not exceed 50% to 60%, oxidative phosphorylation (OXPHOS) still makes a considerable contribution to the ATP of tumor cells. In some cases, there will be an anti-Warburg effect. HCC Warburg effect is closely related to HCC cell proliferation, apoptosis, immune escape, migration and invasion, chemotherapy resistance, and treatment failure. The mechanism of the Warburg effect in HCC is complex, involving the expression of stimulating the key glycolysis enzymes by hypoxia-inducible factor-1(HIF-1), the activation of oncogenes and the inactivation of tumor suppressor genes, the continuous activation of related signaling pathways, the participation of noncoding RNA, and the rate of metabolism gene mutation of enzyme. This article synthetically discusses the characteristics of glucose metabolism in HCC cells, the mechanism of Warburg effect, clinical significance, and corresponding treatment strategies and provides new perspectives for the prevention and treatment of HCC.

HighlightsThe peak breaking force and energy consumption change in maize stalk were predicted by the FEM.A high SADBT reduced the PBFR and PBFS and increased the ECSC.The TRYDB had the most critical effect on the peak breaking force and energy consumption.Abstract. The mechanized retention of stalks is the primary method to avoid open burning. However, the variation in the breaking force and energy consumption in the chopping process of mechanized retention must be clarified. Therefore, based on the finite element method (FEM) and field validation experiments, the effects of various edge-curve types and rotational speeds of disc blades for maize stalk retention on the breaking force and energy consumption were examined. The test indices were the peak breaking force of the rind (PBFR) and stalk (PBFS), energy consumption of stalk chopping (ECSC), and energy transmission efficiency (ETE). The test factors were the spiral disc blade type (Archimedean, logarithmic, and sinusoidal-exponential spiral), slide-cutting angles of the disc blade tip (SADBT, 30°, 40°, 50°, and 60°), rotational speed of the Y-type blade (RSYB, 1400, 1600, 1800, 2000, 2200, and 2400 rpm), and transmission ratio between Y-type and disc blades (TRYDB, 0.25, 0.50, 0.75, and 1.0). The chopping process was divided into the cutting processes of the initial rind, rind and pith, final rind, and stalk end. The results showed that the SADBT, TRYDB, and RSYB had significant effects on the PBFR, PBFS, ECSC, and ETE. The most influential factor on all test indices was the TRYDB. The RSYB positively affected the PBFR, PBFS, and ECSC. The growth rates of the PBFR, PBFS, and ECSC increased with the TRYDB. The maximum PBFR, PBFS, and ETE values were obtained under an SADBT of 60°, and the maximum ECSC value was obtained under an SADBT of 40°. The difference in energy consumption between the field validation experiment and simulation was less than 10%, which proved the correct results of the FEM simulation. Keywords: Energy consumption, Finite element method, Maize stalk, Peak breaking force, Slide cutting.

A novel transparent SrF2/Nd:SrF2/SrF2 composite ceramic with sandwich-like laminar configuration was designed and successfully fabricated by the hot-pressed sintering method. The composite ceramic possesses an apparent transition interfacial (about 200 μm in thickness) between SrF2 and Nd:SrF2 layers, formed by non-uniform distribution of raw powders and the diffusion of Nd ions during the high temperature sintering. The average grain sizes of SrF2 and Nd:SrF2 layers are about 262.1 μm and 28.6 μm, respectively. For a 2-mm thick transparent SrF2/Nd:SrF2/SrF2 composite ceramic hot-pressed at 900 °C for 2 h, the transmittance at 500 nm and 1200 nm are about 49.6 % and 62.3 %, respectively. The microstructure, emission spectra and thermal conductivities of ceramics are also detected and studied.

This work demonstrates a facile and “green” method to prepare eco-friendly, flexible, transparent, and ionically conductive starch-based materials, which have great potential for personal health-monitoring applications such as disposable electrodes. This method relies on the use of the CaCl2 solution and enables both the efficient disorganization and amorphization of high-amylose starch granules with low energy consumption and the reinforcement of the starch chain network by starch–metal cation complexation. Specifically, the method involves a simple mixing of a high-amylose starch with the CaCl2 solution followed by heating the mixture at 80 °C for 5 min. The whole process is completely environmentally benign, without any waste liquid or bioproducts generated. These resulting materials displayed tunable mechanical strength (500–1300 kPa), elongation at break (15–32%), Young’s modulus (4–9 MPa), toughness (0.05–0.26 MJ/m3), and suitable electrical resistivity (3.7–9.2 Ω·m). Moreover, the developed materials were responsive to external stimuli such as strain and liquids, satisfying the requirements for wearable sensor applications. Besides, composed of only starch, CaCl2, and water, the materials are much cheaper and eco-friendly (can be consumed by fish) compared with other polymer-based conductive hydrogels.\ud

The thermodynamic and acoustic behaviors of prefabricated composite wall panel were investigated based on the heat transmission and acoustic principles. Moreover, the thermal conductivity formula of the prefabricated composite wall panel based on thermal conductivity equivalence method was proposed by deducing the solving process of thermodynamic parameters. Changes of sound reduction index and sound pressure level (SPL) of the prefabricated composite wall panel with sound frequency range were analyzed by experimental test and numerical simulation. The research results demonstrate that the thermal conductivity of wall panel can be calculated accurately by the thermal conductivity equivalence method. The calculation model of sound reduction index can be used to determine the sound reduction index in the middle and low frequency ranges. The designed wall panel has satisfying heat insulation and sound insulation with a heat transfer coefficient of 0.55 W/m2·K and about the weighted standard acoustic pressure difference (DnT,w) of 42 dB.

To solve problems of coarse grains and low mechanical performance in low carbon steel parts fabricated by wire and arc additive manufacturing (WAAM), a novel compound arc and vibration shock forging-rolling (CAVSFR) method was proposed in this study. Carbon steel components were fabricated by the proposed method. And results showed that the total deformation of 28.3 % was obtained and the average grain size was reduced from 9.6 μm of WAAM to 6.4 μm. Grain refining was attributed to the static-force rolling, vibration-shock forging and micro self-forging of the molten pool. The large deformation in the medium-high-temperature zone, which provided more nucleation sites, accounted for grain refining in both static-force rolling and vibration-shock forging. Vibration shock greatly promoted dendrite fragmentation and more dendrite fragments were obtained as nuclei for new grains. Besides, the larger constitutional supercooling helped these nuclei survive and induced more nucleation, which could refine grains. These two factors were responsible for the grain refining in micro self-forging of the molten pool. What’s more, the refined grains enhanced the strength and plasticity of the material. The ultimate tensile strength (UTS), yield strength (YS) and elongation of the optimized component manufactured using the proposed method were increased to 555 MPa, 391 MPa and 38.9 %, which were enhanced by 14.2 %, 8.6 % and 1.8 % respectively and exceeded that of the wrought low alloy steel with the UTS of 550 MPa. Compared with other methods, small load and simple equipment could obtain components with the high performance through the proposed method.

Nanoparticle-reinforced metal matrix composite coatings have significant potential in mechanical part surface strengthening owing their excellent mechanical properties. This paper reports a phenomenon in which the grain orientation gradually evolves to (220) as the deposition current density increases when preparing nanoparticle-reinforced nickel-based composite coatings through jet electrodeposition (JED). During the preparation of the Ni-SiC composite coatings, the deposition current density increased from 180 A/dm2 to 220 A/dm2, and TC(220) gradually increase from 41.4% to 97.7%. With an increase of TC(220), the self-corrosion potential increases from −0.575 to −0.477 V, the corrosion current density decreases from 9.52 μA/cm2 to 2.76 μA/cm2, the diameter of the corrosion pits that after 10 days of immersion in a 3.5 wt% NaCl solution decreases from 278–944 nm to 153–260 nm, and the adhesion of the coating increases from 24.9 N to 61.6 N. Compared a conventional electrodeposition (CED), the Ni-SiC composite coating using JED has the advantages of a smooth surface morphology, high corrosion resistance, and strong adhesion, which are more obvious with an increase in TC(220).

A new method was developed to optimize the microwave heating thickness of the spent automobile catalyst in order to improve the uniform distribution of the temperature field. The average penetration depth and the microwave heating thickness of the spent automobile catalyst were calculated by Gauss model and numerical calculation based on dielectric loss tangent and reflection loss. The results showed that the spent automobile catalyst was a medium loss material. The average penetration depth was 1.11 m from room temperature to 800 °C. The optimum microwave heating thickness of the spent automobile catalyst was about 0.83 m or 0.75 times of the average penetration depth. Industrial application analysis indicated that the optimization of heating thickness could improve the uniform distribution of the temperature field and reduce energy consumption.

The field cores taken from the asphalt pavement were soaked for long term after vacuum saturation. The indirect tensile strength, the failure stiffness modulus and the tensile strength ratio (TSR) of samples are determined by the indirect tensile test with or without the freeze-thaw cycles. The indirect tensile test and unconfined compressive strength test are devised to measure the unconfined compressive strength and cohesion of specimens immersed in the water for different period. Moreover, the sensitivities of each mechanical index to evaluate the moisture damage of long-term immersed asphalt mixture were compared. The test results indicate that the indirect tensile strength, failure stiffness modulus, TSR, compressive strength and cohesion of asphalt mixtures were all decreased due to the long-term action of water. After immersion for 540 days, the loss rate of unconfined compressive strength was the highest, reaching 62.6%, followed by cohesion, whose loss rate was 50.6%, indicating that under the condition of high temperature 60°C, the longer the saturation lasts, the more obviously the compressive strength and cohesion change, which are all sensitive to moisture damage. Under low temperature conditions, compared with the indirect tensile strength and TSR, the loss rate of failure stiffness modulus is 36.8%, representing its moderate sensibility to moisture damage. At early stage of 6 months, these mechanical indexes declined rapidly, and then gradually became slower. The free water remaining in the samples continuously infiltrated into the interface between asphalt film and aggregates, resulting in a decrease in the adhesion and the contact angle between them as well as a decrease in the cohesion.

The precise and effective generation and manipulation of micron‐sized droplets is crucial for chemical and biological research and applications. Normally, droplets generation and manipulation are achieved by two separate devices/systems with their respective operation strategies. Pipette, inkjet nozzle, and microfluidic channels equipped with programed syringes are commonly used for droplets generation whereas the subsequent manipulation is normally achieved by leveraging of forces originating either from optical, electric, magnetic or acoustic field and the corresponding complicated devices. Here we report a new paradigm that can realize simultaneous droplets generation and manipulation in an immiscible liquid environment using only the confined interface vibration generated by the ordinary inkjet nozzle. Droplets, ranging from femtoliter to picoliter, can be generated and manipulated without interruption since they are actuated by the same nozzle. Our strategy provides a platform for precise generation and manipulating the micro‐sized droplets that may be valuable for applications requiring simple setups and seamless connection between droplets generation and droplets manipulation.

The use of submicron structures for structural coloration of surfaces has broad applications for color filters, projection displays, virtual reality, and anti-counterfeiting. Currently, structural color images lack high resolution due to low manufacturing accuracy. In this study, the axial-feed fly cutting (AFC) method is proposed to fabricate submicron grooves for the diffraction of visible light to create structural color images. We establish the relationship between the color information in the pixels of the original image and the parameters of the array units corresponding to the pixels. An algorithm to determine groove spacing and the tool path is established, and array units with the desired groove spacing are machined to reproduce the structural color images. The submicron grooves fabricated by AFC have high quality and good consistency. Due to the excellent diffraction performance of the machined grooves, images with high saturation and resolution can be reproduced. It is verified that images with various colors can be efficiently fabricated using the proposed method and algorithm.

To explore some solutions for construction or repair problems, it is necessary to determine the performance of a quick-setting grout such as a sulfoaluminate cement-based grout (SACG). In this study, two typical sulfoaluminate cement (SAC) and one ordinary Portland cement (OPC) were prepared, the water/solid (W/S) ratio was selected as 0.6:1-1.2:1. The properties investigated were: the rheological behaviours, i.e., mini-slump, flowability; the fresh-state properties, i.e., effective W/S or stability, flowability losing time and initial/final setting time; the mechanical performance, i.e., flexural strength (FS), unconfined compressive strength (UCS); the mineral characteristics; microstructure and erosion resistance coefficient. The mechanical strength of blended (SAC+OPC) suspension-sodium silicate double slurries (volume ratios of 1:1-5:1) were determined to provide optimisation suggestions for the double slurries. The results showed that the approximate combination of an anti-washout agent and a superplasticiser should be used, the mineral composition and volume ratio were the main influence factors for the flowability losing times. The strength developments of the SACG were relatively low at high W/S. The strengths of the SAC double slurries are low, and a 10%-30% SAC and volume ratio of 3:1 are recommended if the SACG double slurries are applied. The sulfate erosion resistance coefficients of the SACG were much higher than 1.0 and they have obvious advantages for sulfate erosion resistance.

The crystallinity indices (CrI) of Chinese handmade papers were investigated using the X-ray diffraction (XRD) method. Four Chinese handmade papers, Yingchun, Zhuma, Yuanshu and Longxucao papers were used as model substrates of mulberry bark, ramie, bamboo and Eulaliopsis binata papers, respectively. Two forms of the paper samples, paper sheets and their comminuted powders, were used in this study. The results showed that their XRD patterns belong to the cellulose-I type and Iβ dominates the cellulose microstructure of these paper samples. Moreover, it was found that the microstructures and CrIs of cellulose of these papers were changed by the grinding treatment. This work suggested that the sheet form of the handmade papers is suitable to determine CrI by XRD, despite the contribution of non-cellulosic components in the papers. The order of CrIs for these paper sheet samples was Yingchun, Zhuma, Longxucao and Yuanshu papers. Besides CrIs, differences in cross-sectional areas of the crystalline zone of cellulose can be used for comparing different types of handmade papers. It was also found that the CrIs and crystallite size of paper cellulose varied between the sheet samples and the powder samples, illustrating that the pulverisation has a negative influence on the microstructure of the handmade papers.

As an important carrier of information and culture, paper-based books and relics often suffer from many damages because of their fragile and environmentally sensitive intrinsic structure. Hence, a ...

The dynamic keyhole behaviors are directly observed in laser welding of AH36 steel/glass, and Zirconia particle is used to observe the convective pattern. The weld bead formation, keyhole instability and porosity formation are analyzed. Moreover, the differences in keyhole instability and porosity formation between no magnetic field assisted and magnetic field assisted laser welding are analyzed. With the magnetic field is added, the weld width, small concave, the formation of the keyhole collapse and the convective pattern are similar in laser welding of steel, and the generated Lorentz force hinders the flow of liquid metal. Widening of bottom weld width without undercut defect can be obtained with magnetic field assisted. The lower fluctuation of the weld depth, the longer time of plasma plume above the weld pool, fewer undercuts and spatter defects contributes to the increase of the keyhole stability, and thus restrains the porosity formation. Besides, an easier keyhole open, the larger bubble escape velocity and the lower solidification rate also promote the reduction of the porosity formation.

Cuprous oxide (Cu2O) in high yield with controlled shape and size was synthesized via a solution-phase route by reducing cupric sulphate with D-glucose. The solution pH shows strong effects on the size and morphology of the products. The products were characterized by X-ray power diffraction (XRD) and Scanning electron microscope (SEM). The infrared emissivity of Cu2O was tested by Far infrared emissivity measurer S302. The possible crystal growth processes have been proposed.

The growth mechanism and the corresponding kinetic parameters are valuable to improve the electrodeposition method for preparing Pt-based catalysts. In this paper, the effect of the operation condition on the electrodeposition mechanism has been investigated through experiments and theoretical analysis, and the corresponding kinetic parameters were acquired. The catalytic activity of the deposited Pt catalyst prepared by the pulse current (PC) electrodeposition method was improved, compared with that of the commercial Pt catalyst and the Pt catalyst prepared by the direct current electrodeposition method. The results show that both high current density and high ton/toff in PC electrodeposition could cause large cathode overpotentials, resulting in faster nucleation rate and smaller catalyst particle size, which leads to the better reaction activity of the Pt catalyst. Finally, kinetic parameters including the constants, which relate the nucleation rate with the overpotential, the transfer coefficient and the exchange current density of the electrodeposition process, were determined.

International audience; In this paper, porous partially fluorinated graphene (PFG) for supercapacitors (SCs) was fabricated by a mild and secure one-pot hydrothermal method utilizing weakly coordinating anion BF4− as the fluorine source. The hydrolysis rate of sodium fluoroborate was adjusted by controlling the reaction temperature and PFG containing semi-ionic Csingle bondF bonds was obtained, where the content of semi-ionic Csingle bondF bonds in PFG can be easily regulated. The final experimental results show that the incorporation of fluorine not only modulates the electrochemical properties of the material, but also creates abundant pores. When assembled in a symmetric supercapacitor, the PFG shows a high specific capacitance of 269.7 F g−1 at 1 A g−1 and a superior rate capability with 89.3% capacitance retained, as the current density is increased from 1 A g−1 even to 20 A g−1. Furthermore, the resultant energy density for PFG is 9.4 Wh kg−1 at a power density of 250.0 W kg−1 (1 A g−1). All these results confirm that as-prepared partially fluorinated graphene is appropriate for the application in SCs and mass production.

Non-fullerene acceptors exhibit great potential to improve photovoltaic performances of organic solar cells. However, it is important to further enhance chemical stability and device durability for future commercialization, especially for Y6-series small molecule acceptors with 2-(3-oxo-2,3-dihydroinden-1-ylidene)malononitrile (IC) type as ending group. In this work, an IC-free photovoltaic material YF-CN consisting of 2-fluoren-9-ylidenepropanedinitrile terminal was designed and synthesized by stille coupling. YF-CN exhibited closed-shell chemical structure with enhanced photostability and improved morphological compatibility with the binary PCE10:Y6 blend. The moderate energy level makes YF-CN could serve as a multifunctional material, such as donor, acceptor and the third component. When adding YF-CN as second donor into PCE10:Y6 system, an improved power conversion efficiency of 12.03% was achieved for as-cast device. Importantly, the ternary PCE10:YF-CN:Y6-devices showed enhanced storage durability maintaining 91% of initial PCE after the 360 hours. This work provides new perspective to understand the open-shell character of donor and closed-shell structure of acceptors, respectively, as well as promising design concept of stable IC-free acceptors for organic solar cells.

The construction of a smart city puts forward new requirements for lighting systems, such as variable color temperature adapting to environment and low energy consumption. We introduce a variable color temperature laser lighting system that produces uniform light with minimum energy. The color temperature is controlled by tri-color RGB diode lasers, and uniform lighting is achieved by microlens arrays. Tri-color diode lasers with wavelengths of 650, 556, and 450 nm are used as the lighting sources, and the white light laser output is achieved by combining the three beams. The color temperature is controlled by changing the power ratio of each lighting source. Finally, the homogenization of laser energy is regulated by the microlens arrays, and the energy uniformity reaches 91.1%. Moreover, we do an experiment to compare LED street lighting and laser street lighting, finding that the street lighting system with this design can increase the energy utilization rate by 113.33%, and the color temperature of the car headlamps with this design can be changed according to the environment. Therefore, this laser lighting system is an effective solution for modern smart lighting systems and energy saving, which have vast application.

Glass fibre is a random network structure composed of [SiO4] tetrahedra. The structure contains a large number of defects, which act as crack initiation points. Under tensile stress, cracks undergo crack initiation, stable propagation, failure propagation, and fracture, and the stress that begins after unstable propagation is called the critical fracture stress. When the stress is less than the critical value, the crack is subject to the force of chemical bonds during the crack propagation process, and crack arrest occurs. When the stress is greater than the critical value, the glass fibre will undergo destructive fracture. In this paper, long-term tensile tests were carried out on glass fibre and a glass fibre composite under different constant tensile stress conditions. The fracture times of the glass fibre and glass fibre composite under different tensile stresses were obtained, the critical fracture stress of glass fibre was inferred, and the fracture mechanism was explained.

Polyacrylate resin composite materials with the mineral exhibit super water absorbency and good degradation ability. In this work, expanded perlite and sodium polyacrylate resin composite materials have been prepared with ceric ammonium nitrate (CAN), N,N’-methylene bisacrylamide (MBA), tapioca starch, and expanded perlite. Fourier transform infrared spectroscopy (FT-IR) and field emission scanning electron microscopy (SEM) are used to characterize the bonds absorption peaks and morphologies. The results suggest that the expanded perlite can graft on sodium polyacrylate resin, and the optimal distilled water and 0.9% NaCl absorbency are 1079 and 253 g/g when the expanded perlite content is 8 wt%, respectively. The swelling water model of the composite materials is firstly simulated to be Voigt-based model. In addition, the composite materials absorbency that is influenced by special characteristics of the expanded perlite has been shown.

The China Fusion Engineering Test Reactor (CFETR) is a new superconducting magnet tokamak. The vacuum vessel (VV) is one of the core components of the CFETR device, and it will provide a high-vacuu...

Dielectric properties are some of the main parameters of materials, determining their interaction with electromagnetic energy during microwave heating. The dielectric properties of spent automobile catalyst were measured by using the resonance cavity perturbation technique from room temperature to 800°C at 915 MHz and 2450 MHz. The effects of temperature and frequency on the dielectric constant, dielectric loss factor, loss tangent, and penetration depth were studied. The results indicate that spent automobile catalyst is weakly polar, making it difficult to transform electromagnetic energy into heat. The relaxation time and conductivity obtained by numerical calculations further explain from the microlevel that spent automobile catalyst cannot dissipate electromagnetic energy through dipole loss or conduction loss under microwave irradiation. This work describes an effective way to explore the dielectric heating mechanism and a basis for understanding the interactions between microwaves and spent automobile catalyst.

The X-ray scattering method is investigated in application of characterizing surface roughness of X-ray grazing incidence telescope. The surface figure effect on the scattering diagram of the curved rough mirror is analyzed in detail based on generalized Harvey-Shack surface scatter theory and image formation theory, when smooth-surface approximation is met and the width of the incident beam is about one tenth of spatial wavelength of the surface figure. Based on the analysis, the characterizing scheme is designed and the determination error of the one-dimensional power spectral density function due to the finite width of the receiving slit before the detector is discussed. The scheme is simulated with Zemax and the simulated results verify that the surface figure only affects the measuring accuracy of the low-spatial-frequency surface roughness. The method overcomes difficulty in measuring roughness of the grazing incidence mirror with high resolution conveniently during the development of the X-ray grazing incidence telescope.

In this study, earth-abundant thin film Cu2ZnSnSe4 (CZTSe) solar cells were fabricated by the magnetron sputtering of a quaternary compound target. Precursor films were deposited in a designed chemical composition followed by a selenization process under the mixed atmosphere of an active gas, H2Se, and a carrier gas, Ar. Due to the existence of the Se element within the film, a relatively low concentration of H2Se was utilized to mainly crystallize the precursors and also supplement Se. To explore the selenization process, the as-deposited CZTSe absorbers were annealed at different temperatures. The results of X-ray diffraction (XRD) and Raman scattering spectroscopy measurements showed that the CZTSe grains continuously grew after selenization. In this study, when the absorbers were annealed at 575 °C, the CZTSe solar cells were obtained with the highest efficiency of 11.95%, with the open circuit voltage (VOC) of 432.22 mV, short circuit current density (JSC) of 36.28 mA cm−2 and fill factor (FF) of 76.21%. The photoluminescence (PL) spectrum indicates that the peak center underwent a red-shift from the band gap (Eg) of 90 meV. The analyses of fluctuation modules indicate that the electrostatic potential fluctuation is dominant for the band tail. The investigations demonstrate that sputtering of the Cu–Zn–Sn–Se quaternary compound target via the selenization process can be an effective and simple method for the fabrication of high-performance CZTSe solar cells.

The modification mechanism between nano-zinc oxide (nano-ZnO), polymerised styrene butadiene (PSB) and asphalt were studied by first-principles calculation, revealed the modification mechanism from...

The divertor target is one of the main components enduring the high heat load in fusion reactor. The life time and integrity of the divertor are severely limited by the failure of the target heat sink especially in operation of high temperature and long operating period of China Fusion Engineering Test Reactor (CFETR). Therefore, the study of the failure mechanism of heat sink under long pulse and high-power H-mode operation is one of the bases to ensure the reliability of CFETR. In this paper, the finite element method is used to analyze the structural response of the heat sink to the thermal load of the W/RAFM(Reduced Activation Ferritic–Martensitic) divertor target under CFETR design operating conditions. Then the numerical creep-fatigue damage accumulation model is built to explore the fatigue failure mechanism of divertor target heat sink in high power / long pulse operation during which the stress relaxation is taken into account. The preliminary creep-fatigue assessment of CLAM steel as divertor target heat sink in CFETR design operation phase is presented and provides important theoretical basis for life prediction of heat sink for future fusion reactor.

Single-point diamond cutting is an efficient method to fabricate microlens arrays (MLAs). However, machining MLAs at the microscale with high dimensional accuracy and a smooth surface finish is a difficult task. In this study, a method of profile cutting is proposed to machine MLAs on electroless nickel–phosphorus (Ni–P) plating. To improve the dimensional accuracy of MLAs, a precision tool setting method is introduced, via which the precision of MLA sag can be controlled to within 20 nm. In addition, the formation mechanism of corrugation defects is studied via a finite element (FE) simulation of the wedge nano-cutting process and a cutting experiment of concentric ring grooves. By optimizing the tool settings and the machining parameters, high-quality MLAs with apertures of Φ100 μm can be created.

Metal–organic frameworks (MOFs) are an attractive class of hybrid materials with metal clusters and organic linkers. The unusual properties of MOFs, such as permanent nanoscale porosity, high surface area, uniformly structured cavities and the availability of in-pore functionality and outer-surface modification, are advantageous using as lipase immobilization platform. Herein, we covalent immobilized CALB onto MOFs and then evaluated the biocatalyst performance in the esterification of oleic acid with methanol for biodiesel production. Experimental data about the methanolysis process was evaluated by response surface methodology. The highest yield of 98.9 ± 0.4% was obtained under the optimized conditions: methanol/oil ratio of 3.65:1, a reaction temperature of 46.3 °C, a CALB@MOF loading of 117.77 mg and a reaction time of 11.55 h, which was closed to the predicted value (100.00%). Verification experiment confirmed the validity of the predicted model.

Two kinds of dual-wavelength excitable fluorescent Lyocell fibers, which can be excited by short-wavelength UV/IR or long-wavelength UV/IR radiation, were prepared by dry-jet wet spinning. These fluorescent Lyocell fibers can emit two different fluorescence wavelengths at two different excitation wavelengths, exhibiting double anti-counterfeiting functions, thereby providing higher security. SEM-EDX analysis showed the uniform phosphors distribution in Lyocell fibers. The fluorescent Lyocell fibers were mixed into pulp for papermaking. Addition of dual-wavelength excitable fluorescent Lyocell fibers had no influence on brightness and opacity of papers, and the mechanical properties of papers were similar or even higher than paper with addition of pure Lyocell fibers, although the introduction of phosphors decreased the mechanical properties of Lyocell fibers slightly. Our results proved that dual-wavelength excitable fluorescent Lyocell fibers can be used not only in textile fibers, but also in papermaking to develop various security paper products.

Reliability and security of the fusion device are severely affected by the failure of the divertor. It is necessary to have a reliable life prediction for heat sink in W/CuCrZr divertor target, especially during long-term high heat flux operation in future fusion devices in which the high temperature creep accelerates its fatigue failure. In this study, a new approach to creep life was applied to creep-fatigue damage accumulation model for CuCrZr heat sink. It is proved that the results of new method for CuCrZr creep life calculation is more consistent with the experimental results than the previous empirical formula. Then the temperature and stress/strain results were calculated for two types of ITER-like monoblock using thermal–mechanical analysis which shows that high temperature creep could not occur on EAST divertor heat sink of current operating conditions. Based on creep-fatigue damage accumulation model, the predicted life of monoblock for DEMO divertor are given under different operating mode respectively. The model provides theoretical basis and guidance for the divertor engineering design of future fusion reactor like CFETR and DEMO in which the high temperature creep in heat sink must be taken into account due to long-term operation.

The shock tube can form a good plane wave, The cryogenic shock tube experiment has more phenomena than the room temperature shock tube experiment, evaporation and condensation will occur. The cryogenic experiment of shock tube is very important. Low temperature experiments verified the relationship between the condensing film and shock wave. With the development of aerospace technology, there is a lack of experimental devices for cryogenic shock wave. In this paper, a diaphragm less shock-absorbing tube with higher working efficiency is used. The low-pressure part of the diaphragm less shock tube is designed as a cryogenic device, and the low-temperature characteristics of the shock wave in the shock tube are studied. Finally, fluent is used to numerically simulate the shock wave flow state.

The primary goal of this study is to find an easy and convenient way to estimate the degree of compaction in real time for compaction quality control. In this paper, an artificial neural network classifier is developed to identify the different characteristic patterns of drum vibration and classify them according to the different compaction levels. At first, a field compaction experiment is designed and performed in a construction site, and the degree of compaction and the vibration are measured. Then, the vibration signals collected from the experiment are processed to extract the features of vibration patterns and labeled with the compaction level to train the artificial neural network model. At last, the performance of the artificial neural network classifier is verified against the degree of compaction measured by using a nuclear density gauge. It can be found that artificial neural networks show good performance and huge potential for the problem of compaction quality control.

Mg6Ti5O16 ceramics have been prepared by the conventional solid-state route using Mg(OH)2 as the magnesium source and their sinterability, phase composition and microwave dielectric properties were...

Ultrafast laser-induced surface modification of materials has attracted significant attention in recent years. The mechanism of formation of ultrafast laser-induced periodic surface structures (LIPSS), which were evenly distributed over the large area of indium tin oxide, was studied both theoretically and experimentally. Films were deposited using 10-ps 1064-nm laser. Resistance and transmission characteristics of LIPSSs on ITO film were analyzed. The resistance of LIPSSs increases with the increasing of transmittance in infrared band within a certain range. The paper reports the optimal processing parameters for the realization of LIPSSs on ITO films established based on the resistance and transmission properties of the film. The film with the optimized structure can significantly improve the infrared transmittance function of ITO while ensuring the low resistance, which can greatly improve the power generation efficiency of the thin film solar cells.

Carbon nanotubes (CNTs)/Cu2O-CuO composite powder was fabricated by a spray pyrolysis (SP) method. The copper acetate monohydrate (Cu(CH3COO)2·H2O) solution within CNTs dispersion was used as a precursor. The influences of decomposition temperatures, concentration of Cu(CH3COO)2 solutions and CNTs mass fractions on the constituent phases and microstructures of the composite powder were investigated by XRD, FESEM, TEM, UV–Vis analysis methods. The results show that the composite powder prepared at 500 °C, with the concentration of 1.0 g/l Cu(CH3COO)2·H2O and 30.0 wt.% CNTs mass fraction, has the best photocatalytic performance due to the numerous particles precipitated on the CNTs surface and lower recombination rate of the photogenerated electron-hole pairs. Furthermore, tentative mechanisms of the nucleation-growth and photodegradation properties were explored based on the microstructure and photocatalytic analysis.

Electromagnetic railgun is a new concept weapon that uses electromagnetic force to launch projectiles. However, it differs from conventional guns in that the strong pulsed magnetic field of Tesla level will be produced in-bore during the launching process, which will cause the failure of electronic devices in the control circuit. In order to protect the circuit from electromagnetic interference (EMI), this paper designs a packaging method of combined shielding. The magnetic induction intensity on data storage system before and after shielding have been tested. The results show that this method can effectively restrain the EMI, and the electromagnetic shielding effectiveness (EMSE) can reach 8.5dB.