Forming process control of powder bed fusion (PBF) additive manufacturing (AM) is the key to produce high-quality qualified parts. In this paper, spreading powder process and electron-beam melting (EBM) of Ti6Al4V powder were simulated based on simulation technology, and the state of powder bed powder and melting trajectory characteristics were characterized. Firstly, the particle size distribution of Ti6Al4V powder was tested, and the particle diameter of normal distribution for simulation was determined. Then, the simulation models of spreading powder and EBM model were established. Finally, based on the simulation results, the effect of processing parameters on the quality of powder laying is analyzed, and the morphology of EBM melting trajectory is characterized.

Carbon nanotubes (CNTs) have unique characteristics which make them a suitable reinforcing agent in Aluminum Metal Matrix composites. This review summarizes the work carried out in the field of the microstructure design of CNTs/Al composites. By designing the microstructure of CNTs, Al matrix and their composite interface, the problems of agglomeration, entanglement and dispersion of CNTs, wetting and bonding with Al matrix can be effectively solved, and mechanical properties such as Young’s modulus and yield strength can be improved. Such microstructural design includes metal plating on the surface of CNTs, deposition of nano-ceramic particles, Al matrix ball milling and flakes, grain refinement combined with bimodal-grain strengthening of coarse grains.

Using poly (ethylene oxide)-poly (propylene oxide)- poly (ethylene oxide) (P123), tetraethyl silicon (TEOS), HCl, n-butanol as raw materials, SBA-15 template was prepared by liquid phase reaction method. Using SBA-15 as template, Cu(NO3)2·3H2O and Co(NO3)2·6H2O as raw materials and n-hexane as solvent, mesoporous CuCo2O4 composite metal oxide was prepared by hard template nano-casting. The composite metal oxides were characterized by thermo gravimetric differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Taking benzyl alcohol as the target, the effects of reaction temperature, different catalyst dosage, reaction time and molar ratio of benzyl alcohol to hydrogen peroxide on selective oxidation of benzyl alcohol by CuCo2O4 were studied, and the oxidation products were analyzed by high performance liquid chromatography (HPLC) and nuclear magnetic resonance (NMR). The results show that the sample of CuCo2O4 metal composite calcined at 700 °C has the highest purity, and the average particle size is about 500 nm. The optimum conditions for selective oxidation of benzyl alcohol by CuCo2O4 are reaction system temperature of 80 °C, catalyst dosage of 8 g/L, reaction time 3h, the molar ratio 1:1 of hydrogen peroxide to benzyl alcohol. Under the optimum condition, the conversion rate of benzyl alcohol is 78.13% and the recovery rate of benzaldehyde is 56%. Mesoporous CuCo2O4 is a composite metal oxide with good selective oxidation of benzyl alcohol, which has a wide application prospect.

Since 1986, the first microcantilever applied in atomic force microscope, the device manufacturing technology, driving method and readout technology have improved significantly. In this paper, five readout technologies will be introduced in detail, and they are optical readout, piezoelectric readout, piezoresistive readout, capacitance readout and electron tunneling readout, respectively. Among them, the piezoresistive readout technology attracts a large number of researchers due to simple detection equipment, easy integration, and lower cost. In order to improve the detection accuracy of the piezoresistive microcantilever, a detection system based on FPGA is proposed in this paper. Output signal of the piezoresistive microcantilever array sensor for alpha-fetoprote (AFP) detection was researched. The detection accuracy of 0.05 Hz is achieved, the system stability is within 0.6 Hz, and it has a precise detection level for AFP with concentration of 50 pg/ml, which makes microcantilever has potential in early diagnosis and detection of liver cancer.

In order to explore the best graphene raw materials for the preparation of graphene-aluminum matrix composites by high-energy ball milling. The graphene-aluminum matrix composites were prepared by high-energy ball milling and vacuum hot pressing sintering, and the mechanical properties of the composites were tested. The enhancement effect of reduced graphene oxide (R-GNPs), multilayer graphene (M-GNPs), and graphene oxide (GO) was analyzed by SEM, TEM, XRD, XPS, and FT-IR spectroscopy. The results show that the enhancement effect of graphene oxide is more significant, the tensile strength can reach 329.256 MPa, and the hardness is 136.3 ± 5 HV. GO forms a sandwich-type composite structure in the 2024 aluminum alloy matrix under the action of high-energy ball milling, and the formed composite structure avoids the agglomeration of graphene during the composite process. During the sintering process, GO undergoes thermal reduction to form reduced graphene oxide, which improves the mechanical properties of the composite.

A water-soluble fluorescent conjugated molecule (F-DPP-F) was prepared by introducing peg side chains to improve aqueous solubility, employing molecular design of D-A-D structure to reduce the size, and using electron withdrawing DPP as the acceptor unit. Then the optical properties of nanoparticles were analyzed by UV-vis-NIR. The nanoparticles were evaluated for safety using a cytotoxicity test, and the photothermal properties were characterized.

With the improvement of national living standard, electricity consumption has become an important part of national economic development. Under the influence of “carbon neutral” target in recent years, many power companies have combined the construction of substations with new energy solar energy to achieve low carbon emission reduction and bring profit for the company. In order to achieve the effective use of resources and the maximum conversion rate of photovoltaic energy, this project designs a fixed adjustable photovoltaic bracket structure which is easy to adjust and disassemble, and compares the advantages and disadvantages of existing photovoltaic brackets in actual use, proposes an innovative and optimized design, and uses finite element analysis software to carry out mechanical Structural analysis was conducted to verify the rationality of the design. Save construction materials, reduce construction cost, provide a basis for the reasonable design of PV power plant bracket, and also provide a reference for the structural design of fixed adjustable bracket in PV system.

Low-fired MgTi0.9Zr0.1O3-xwt%2LiF-B2O3-2Bi2O3 (LBB, 1.0 ≤ x ≤ 9.0) ceramics are fabricated via a conventional solid-state reaction route. The effects of LBB additive on phase composition, sintering behavior and dielectric performance of MgTi0.9Zr0.1O3-based ceramics are researched. Sintered samples displayed a MgTiO3 phase accompanying with Mg2TiO4 and Bi2O3 as the second phase. LBB doping successfully reduced sintering temperature of MgTi0.9Zr0.1O3-based ceramic from 1300 °C to 850 °C. The dielectric property of MgTi0.9Zr0.1O3-LBB systems depended on LBB additive. Typical, MgTi0.90Zr0.10O3-5.5 wt%LBB ceramic exhibited good dielectric property of εr = 18.4, Q × f = 23100 GHz and τf = −52.8 ppm/°C at 900 °C.

Gadolinium Oxide doped with various concentrations of Europium (III), were prepared using the solid-state reaction method. Sample with 1.5 mol% of Europium underwent the XRD characterisation to examine the phases available and to confirm the presence of proper phases in prepared samples. Observed XRD pattern exhibited significantly good resemblance with crystallographic open database card No. 96-101-1289, specifically reported for Gd2O3 with cubic structure and I 21 3 (199) space group. Prepared samples were studied using Photoluminescence (PL) emission spectra. The PL emission expressed various peaks centred at 470, 496, 515, 540, 550, 592 and 616 nm out of which peaks centred at 470, 496, 515, 540 and 550 nm were attributed to 6G11/2, 6G9/2, 6G5/2 6P7/2, peak centred at 592 nm is assigned to 6G7/2 6P7/2 whereas the peak centred at 616 nm may correspond 6G11/2, 6G9/2, 6G5/2 6P3/2 transitions. CIE coordinate was found as (0.40, 0.43) which is under the region described for white light emission. Correlated Colour Temperature (CCT) was estimated as 3853 K and Colour Rendering Index (CRI) was 61. Obtaining CRI in this range enabled us to conclude that emission received is satisfactorily good so far as its application in White LED is concerned.

The MgTiO3-x wt%CuO-Bi2O3-Nb2O5-LiF-SiO2 (CBNLS, 4 ≤ x ≤ 10) ceramics were prepared by a solid-state reaction method for developing low-fired microwave dielectric ceramics. The sintering temperatures of MgTiO3 ceramics were successfully lowered to 1000 °C due to CBNLS liquid phase sintering. With increasing x, the dielectric constant (εr ) increased from 16.5 to 18.6 and the quality factor (Q × f) decreased from 13,920 to 4460 GHz, respectively. The well microwave dielectric properties of ɛ r = 16.9, Q × f = 7567 GHz, and τf = −54.7 ppm/°C were obtained for MgTiO3-6wt% CBNLS ceramics.