Low cost co-precipitation method was used to synthesize Cu (0–0.05) doped MgO samples with fixed concertation of Zn=0.01. X-ray diffraction (XRD) spectra confirmed the phase purity of the samples for 0⩽Cu⩽0.03 doping concentration. The secondary phase for 0.04⩽Cu⩽0.05 exhibited the formation of mixed metal oxides. The crystallite size was found to increase from 17.5 to 23.5 nm for 0⩽Cu⩽0.03 and then decreased from 22 to 18.5 nm for 0.04⩽Cu⩽0.05. The estimated bandgap first reduced from 5.48 to 4.88 eV and then increased from 5.21 to 5.36 eV. The morphology of the samples transformed from spheroidal shape to star-like shape. The obtained results reveal that the structural and optical property are in good agreement with the morphological transition. The peak shifting towards the lower values of vibrational frequency from 694 to 579 cm⁻¹ confirms the incorporation of Cu/Zn in Mg-O lattice. The tuning of optical bandgap and structural properties with varying dopant concentration in MgO nanomaterials can be used for multifunctional modern energy storage and optoelectronic devices.

Using chitin as the templating material, we obtained layered nanocomposites like shrimp or crab shells via a sol-gel self-assembly process. SEM images show a layered structure and XRD patterns present a typical peak of chitin, which indicates the templating role of chitin in the as-received hybrid samples. Additionally, the layer spacing of chitin/silica hybrid materials is reduced with increasing content of silica. After the heat treatment for carbonization, layered SiOC nanocomposites with mesoporous structures were obtained and showed good dye adsorption performance. The present study demonstrates a reliable and self-assembly synthesis technique for the development of advanced high-performance nanocomposites with biomimetic nanostructures.

We have obtained vertically aligned ZnO nanowire arrays synthesized by microwave-assisted heating method with different growth time. From the room-temperature PL measurement, the strong deep-level emission and weak near band edge (NBE) emission can be seen. The deep-level emissions became weaker and deep-level emissions became stronger when the samples were annealed at 300 °C for 30 min, meanwhile, the NBE emission peaks get red-shifted with growth time, and the longer the growth time, the more the peak shifting. This phenomenon can be attributed that the diameter of ZnO nanowires increases with growth time. This PL emission phenomenon is important in research of optoelectronic application.

The preparation and the microstructure of GaAs embedded with Al nanocrystals prepared by Laser molecular beam epitaxy were investigated. The microstructure of the sample was observed by transmission electron microscope. The reflection high-energy electron diffraction (RHEED) pattern varied from the stripe pattern to the spot pattern at the beginning of the Al nanocrystals growth, and then the spot pattern tended to change to the stripe pattern. There was a large lattice mismatch between Al and GaAs substrate, and Al formed three-dimensional islands on the GaAs substrate, which led to the RHEED transformation into the spot pattern. Otherwise, the dislocations would be formed between the GaAs layer and Al islands due to the large lattice mismatch. Meanwhile, there was some polycrystal of GaAs around the Al islands.

The bifacial n-PERT (Passivated Emitter Rear Totally diffused) solar cells were fabricated using a simplified process in which the activation of ion-implanted phosphorus and boron diffusion were performed simultaneously in a high-temperature process. For further efficiency improvement, the rear side doping level was regulated by applying two different implantation doses and the chemical etching step of boron rich layer (BRL) was added, and their effects on cell performance were investigated. The solar cells average efficiency reaches 20.35% with a bifaciality factor of 90% by optimizing rear side doping level, which can be explained by the decrease of Auger recombination. And it is further enhanced to 20.74% by removing the front side BRL due to the improvement of surface passivation and bulk lifetime. The improved fabrication process possesses the advantages of low complexity and cost and high cell efficiency and bifaciality factor which could provide a promising way to the commercial production of bifacial n-PERT solar cells.

ZnSnO₃ microspheres was compounded by hydrothermal method with sodium alginate (SA) as a crystal growth modifier, and the Au nanoparticles were decorated on the surface of ZnSnO₃ microspheres by simple solution method and heat treatment process. The structure and morphology of the prepared samples were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Under ultraviolet (UV) irradiation, the 0.2wt% Au/ZnSnO₃@4g/L SA sensor could detect HCHO and reached a good response of 18.8 at 20 ppm, which was three times higher than the ZnSnO₃ in the absence of Au. This sensor also performed an outstanding linearity within 5–20 ppm HCHO and satisfied repeatability. Moreover, the possible mechanism of the influence of Au on gas sensitivity is also proposed.

To study the effect of free radical photocurable passivation film modified by titanate coupling agent for hot-plated aluminum-zinc plate, trimethylpropane triacrylate (TMPTA) and 2-phenoxyethyl acrylate were used as active diluents, a mixture of modified epoxy acrylate and modified polyester acrylate in a certain proportion was used as an oligomer, 2-methyl-1-[4-(methylothyl) benzene] -2-morpholine acetone (907) was used as a free radical photoinitiator, isopropyl thioxanthone (ITX) was used as sensitizer, and bis (dioctyl phosphate acyl) titanate ethyltitanate acrylamide chelate (FD-812) was used as corrosion inhibitor modifier. After UV-curing, the passivation film was characterized by neutral salt spray test, electrochemical testing and other methods. The general performance of the passivation film may meet the requirements of downstream users of hot aluminum-zinc steel plate. The neutral salt spray test, electrochemical testing and microscopic surface morphology analysis of passivation film are in agreement. The introduction of titanate components may effectively promote the photocuring of free radicals. There have been few reports on the titanate coupling which is added to UV-curing coating formula. The titanate coupling agent contains acrylamide groups and terminal amine groups, acrylamide group has oligomer and crosslinking monomer, the terminal tertiary amine groups can provide hydrogen protons, reduce oxygen polymerization, and a phosphating film is formed on the surface of the metal substrate to improve the adhesion and corrosion resistance of the coating.

LiFePO₄ cathode was successfully co-coated by ZrO₂ and N-doped carbon layer based on the coprecipitation of Zr species and polydopamine on the LiFePO₄ surfaces. The mutual promotion between the hydrolyzation of ZrO₂ precursor and the self-polymerization of dopamine was realized in the one-step synthesis. After being used in the coin battery as cathode material, the ZrO₂ and N-doped carbon co-coated LiFePO₄ displayed improved cycling stability (97.0% retention at 0.2 C after 200 cycles) and enhanced rate performance (130.7 mAh·g⁻¹ at 1 C) due to its higher electrochemical reactivity and reversibility compared with those of commercial LiFePO₄.

Glutaraldehyde (GA) crosslinked chitosan (CHIT) was modified on nylon fibers. Afterwards, pyrrole was in-situ polymerized on the surface of the CHIT/Nylon fiber. The SEM and FT-IR results show that the functional fiber is successfully prepared, and the obtained polypyrrole (PPy) presents nanorods morphology on the fiber surface. The mechanical properties of the fibers were studied by Instron. The organic electrochemical transistors based on PPy/Nylon fiber, PPy/CHIT/Nylon fiber, and PPy/GA-CHIT/Nylon fiber as channels were prepared and their transistors performance was compared. It is found that PPy/GA-CHIT/Nylon fiber-based transistor has great output, transfer, transient curves, and excellent transconductance of 6.8 mS, providing a new platform for the field of wearable devices. Furthermore, the study introduces chitosan material with excellent biocompatibility, which makes prepared transistors also have potential applications in the field of biosensing.

Reduced graphene oxide (rGO) enhanced B₄C ceramics was prepared by SPS sintering, the enhancement effect of rGO on the microstructure and mechanical properties of composites was studied through experiments and numerical simulation. The results show that the composite with 2wt% rGO has the best comprehensive mechanical properties. Compared with pure boron carbide, vickers hardness and bending strength are increased by 4.8% and 21.96%, respectively. The fracture toughness is improved by 25.71%. The microstructure observation shows that the improvement of mechanical properties is mainly attributed to the pull-out and bridge mechanism of rGO and the crack deflection. Based on the cohesive force finite element method, the dynamic crack growth process of composites was simulated. The energy dissipation of B₄C/rGO multiphase ceramics during crack propagation was calculated and compared with that of pure boron carbide ceramics. The results show that the fracture energy dissipation can be effectively increased by adding graphene.

The nitrogen-doped carbon dots (N-CDs) were prepared by using coke powder as carbon source and one-step hydrothermal method. The N-CDs were studied as a fluorescent chemosensor for determining Cr(VI) in water. The selective, sensitive, reproducibility and stability of as-prepared N-CDs were investigated. The morphology, composition and properties of N-CDs were characterized by a series of methods. The fluorescence quenching of N-CDs by Cr(VI) was explored. The experimental results reveal that the obtained N-CDs have great hydrophilicity and strong luminescence properties, which demonstrates the successful doping of nitrogen into the CDs. The surface-active groups and emission wavelength range of CDs increase due to the electronegativity and electron donor effect of doping N atom. Furthermore, the N-CDs exhibit good photochemical properties for the detection of Cr(VI), including a wide linear range from 0.3 to 200 µM (R ²=0.9935) and a low detection limit of 0.10 µM at the signal-to-noise ratio of 3 (S/N=3). Moreover, the N-CDs as a sensor was used successfully for Cr (VI) detection in real water samples with recovery rates of 99.9%–110.6%. This sensor also shows highly reproducibility and stability. The N-CDs fluorescent chemical sensor may be a potential candidate for applying in the field of other fluorescent chemical sensing, catalysis, photoelectric devices and other fields.

TiO₂/graphene composite was synthesized in the vapor environment of isopropanol. In order to improve the properties of composite, N-doped of TiO₂/graphene with different N/Ti molar ratio was prepared in the vapor environment of deionized water and used urea as the source of nitrogen. The N-doped occupies in the interstitial sites of TiO₂ lattice, substitutes for O element in TiO₂ and for C element in graphene, and simultaneously changes the chemical states of Ti and O elements in TiO₂. N-doped changes the morphology of TiO₂ from nano-sheets to nanoparticles, accompanying with the decrease in specific surface area of the composites, first increases the particle size of TiO₂ and then decreases, and alters the vibration modes of Ti-O-Ti. The composite with R _N/Ti=2 exhibits the enhanced photocatalytic degradation performance to methylene blue, and the degradation rate increases from 7.7×10⁻² min⁻¹ for the undoped composite to 9.6×10⁻² min⁻¹.

Bimetallic Pd-Cu/Al₂O₃ was prepared by wetness impregnation method and its catalytic activity on coupling reaction of pyridine to 2,2′-bipyridine was assessed in view of the effects of different molar ratios of Pd:Cu. It is found that Pd-Cu/Al₂O₃ has the small particle size and good dispersion through the characterization. Compared with Pd/Al₂O₃, Pd-Cu (1:2)/Al₂O₃ is the preferable catalyst under the optimum conditions of 1 MPa N₂ pressure, 310 °C and 16 h. The conversion of pyridine is 35.4%, and the selectivity for 2,2′-Bipyridine is up to 99%, which is much higher activity than Pd/Al₂O₃. The directly coupled synthesis meets the requirements of the atomic economy better. The addition of Cu also reduces the dosage of Pd and lowers the cost. It is worth noting that the recycled Pd-Cu/Al₂O₃ catalyst still shows high activity and stability after three times.

Li₂O-Al₂O₃-SiO₂ based glasses were investigated as potential protection glass for electronic devices due to their excellent mechanical properties, such as high hardness, toughness, and scratch resistance. In this paper, Li₂O-Na₂O-Al₂O₃-SiO₂ glass with different Li₂O/Na₂O ratio components were prepared by melt-quenching method, and the effects of Na₂O/Li₂O ratio on the glass densities, structure, thermal, mechanical properties, and chemical stabilities were studied. The experimental results indicate that the glass transition temperature increases with the increases in Na₂O/Li₂O ratios, due to larger ion radius. While the thermal expansion coefficient slightly decreases from 11.4 × 10⁻⁶ to 11.09 × 10⁻⁶/°C. The elastic modulus increases from 57 to 72 GPa. The bending strength reaches maximum 80.90 MPa when the Na₂O/Li₂O ratio is 1.7, then decreases as the ratio further increases. In addition, the Vicker’s hardness gets to 7.37 GPa with largest Na₂O/Li₂O ratio. Moreover, the dielectric loss and dielectric constant increases as the ratio increases. The Raman structure analysis shows the Q₄ [Si-O-Si] decreases as Na₂O/Li₂O ratio increases, which is responsible for the characteristic properties change. Moreover, the glass shows lowest mass loss in 10vol% HF solutions when the ratio is 1.4, while 1.7 in 5wt% NaOH solution.

In order to solve the problem of cracking of ZTAP (Zirconia toughened alumina ceramic particles) reinforced HCCI (high chromium cast iron) matrix composites, the quenching process was optimized. ZTAP reinforced HCCI matrix composites were prepared by infiltration method with gravity sand casting. The thermal expansion curves of HCCI and the composites were measured at different cooling rates by Glebble-3500. The microstructure of the HCCI matrix and the composites were characterized by X-ray diffraction, light microscopy, SEM, ESD, and EPMA. The tested mechanical properties include Rockwell hardness and impact toughness. The deformation differences of HCCI and the composite at different cooling rates were obtained according to the test results of thermal expansion coefficient curve and changes in microstructure and mechanical properties, and air cooling was the most favorable for the composites to have good hardness and not easy to crack. The cooling rate during air cooling is approximately equal to 21 °C/s in this work. When the quenching process was air cooling, the impact toughness and hardness of the composites are 3.7 J/cm² and 61.8 HRC, respectively, and the deformation difference between the composites and HCCI was 20 µm at 300 °C.

To prevent hydrogen-induced loss and achieve long-term effective parameters monitoring in harsh downhole environment, we proposed a Fabry-Perot sensor with vacuum sputter deposited carbon coating film, in which we employed a deposition technology with a higher particle kinetic energy, closer substrate adhesion, and denser films, to deposit the coating film on the surface of the quartz capillary glass tube to protect the sensor from corrosion. The sensitivity and accuracy of the Fabry-Perot sensor with carbon film deposition can reach 369 nm/MPa and 0.02% FS, respectively. Meanwhile, the sensor has less hysteresis error and good pressure linearity of more than 0.99999 for repeatable pressure measurement. The downhole practice monitoring data indicated that this fiber-optic sensor exhibited excellent performance and the sputter deposited carbon coating can effectively decrease hydrogen loss.

Cu60Ni40 alloy was taken as the research object. The alloy was undercooled by fluxing method and circulation superheating method, and the solidified samples with different undercoolings were obtained by natural cooling method. The solidification process of undercooled melt was photographed by high-speed camera, and the transformation of solidification front morphology was studied. The microstructure and morphology of all undercooled samples were analyzed. It is found that the microstructure and morphology of Cu60Ni40 alloy change through the evolution process of “coarse dendrite-equiaxed crystal-oriented fine dendrite-equiaxed crystal” with the undercooling. Finally, the electron backscatter diffraction characterization of 261 K grain refinement structure shows that recrystallization occurs in the grain refinement structure with high undercooling, such as high proportion of high angle grain boundaries, random orientation of equiaxed grains and a large number of annealing twins found in the microstructure.

Selective laser melting (SLM) or Laser-based powder bed fusion (LBPF) is gaining much attention for the fabrication of novel materials with complex shapes, improved functionalities, and properties. An attempt has been made to fabricate hard and brittle silicon via SLM in the absence of any cracks. Two different powder batches were used, where one of the powder batches has 0.3wt% Fe and the other batch with 0.02wt% Fe. The parameter optimization process shows that the SLM Si samples were successfully fabricated from the powders with the minor addition of Fe. The deliberate addition of Fe facilitates heterogeneous nucleation of Si and aids in absorbing the laser energy beam more efficiently. SLM Si samples with 98.5% theoretical density were fabricated with a hardness of around 10.65±40 GPa. The experimental results show that SLM can successfully fabricate Si without cracks and with near theoretical density (of 99%) and complex shapes, which opens their use in wider industrial applications.

A series of Sm doped ZnO based thermoelectric materials were prepared by mechanical alloying and spark plasma sintering. The effects of Sm doping on ZnO based thermoelectric materials were systematically studied by means of electrical and thermal properties tests combined with first principles calculations of energy band, density of states and elastic constants. The experimental results show that the substitution of Sm at Zn site could cause the valence band and conduction band moving down, and the 4f orbitals of Sm could contribute to the increase of the density of states near the Fermi level, corresponding to the increase of carrier concentration and electrical conductivity. The substitution of Sm at Zn site could cause the decrease of effective mass and Seebeck coefficient. The substitution of Sm at Zn site could lead to the decrease of Young’s modulus and lattice thermal conductivity, which contribute to the decrease of thermal conductivity. Finally, the highest dimensionless thermoelectric figure of merit (ZT) value has been increased to 0.346, which is 3.48 times as pristine ZnO.

Silicon nitride (Si₃N₄) supported cobalt catalysts (Co/Si₃N₄) were fabricated by using wetness impregnation procedure. The microscopic morphology, phase composition, and electronic states were characterized by XRD, TEM, SEM, and XPS, respectively. For comparison, cobalt catalyst supported on SiO₂ (Co/SiO₂) was also investigated. XPS studies and DFT calculations show that the cobalt species in Co/Si₃N₄ have lower valence state than those in Co/SiO₂. The catalytic ESR reactions demonstrate that Co/Si₃N₄ exhibits distinctly higher catalytic activity and hydrogen selectivity than Si₃N₄ support and Co/SiO₂ catalyst with the identical cobalt loading, indicative of the favorable effect of Si₃N₄ support on the catalytic performance of supported cobalt catalyst. Durability tests and TG-DSC studies show that Co/Si₃N₄ catalyst exhibits better stability and resistance to coke during the same catalytic experiment period.

We reported sol-gel-derived Nb-doped SnO₂ which is an effective catalyst carrier for deposition of IrO₂, and the electrocatalytic activity of the synthesized catalysts for OER was investigated. It is found that the doping of Nb can refine the SnO₂ crystal grains and improve the electrical conductivity of SnO₂. When the doping amount of Nb is 7%, the electrical conductivity of Nb-SnO₂ reaches a maximum value of 3.54 S/cm. With the increase in the loading amount of IrO₂, the electrocatalytic activity towards OER of the thus-synthesized catalysts is improved, reaching a comparable OER activity with pristine IrO₂ with the loading content of about 44wt%.

A new type of lightweight AlNiLa medium entropy amorphous alloy composite ribbons (labled as MEAAC ribbons) were prepared by vacuum arc melting technology and high-speed single roller melt-spinning method. The microstructure and thermal stability of MEAAC ribbons were examined using X-ray diffraction, differential scanning calorimeter, and scanning electron microscope. Meanwhile, the hardness and surface roughness of these ribbons were measured by Vickers microhardness tester and atomic force microscope. The potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS) were applied to investigate the corrosion behavior of these MEAAC ribbons in simulated seawater (3.5wt% NaCl corrosive solution) at room temperature. The results demonstrate that AlNiLa MEAAC ribbons in the as-received state are mainly composed of amorphous phase and intermetallic compounds. The hardness values of all melt-spun ribbons are above 310 HV_0.1. With the increase of Al content, the linear polarization resistances of four various AlNiLa MEAAC ribbons are negligibly different numerically. It is also found that Al₄₅Ni_27.5La_27.5 MEAAC ribbons have the most positive corrosion potential and the smallest corrosion current density at the same time; hence it may be a kind of potential material for metal surface protection in harsh ocean environment.

The impact of magnetic field on the corrosion behavior of Al-Mg-xR_E/Fe alloys in NaCl solutions with concentrations of 1.5wt%, 3.5wt%, and 5.5wt% were studied by microstructure observation, immersion test, and electrochemical test. The combined impacts of magnetic field and chloride ion concentration on the corrosion behavior of Al-Mg alloys with various electrode potential phases were discussed. The results indicate that Al-3.0Mg-xR_E/Fe alloys corrode faster and have a higher pitting corrosion potential in the NaCl solution with a higher concentration. In addition, a magnetic field can lower the pitting sensitivity and corrosion rate of Al-3.0Mg and Al-3.0Mg-0.2R_E/Fe alloys in NaCl solution with different concentrations. However, at a higher concentration of NaCl solution, the magnetic field has a weaker inhibiting effect on corrosion rate and pitting sensitivity. In NaCl solutions with concentrations of 1.5wt% and 3.5wt%, the corrosion rate and pitting sensitivity of Al-3.0Mg-1.0R_E/Fe alloys can be reduced by a magnetic field. However, in NaCl solution with the concentration of 5.5wt%, the corrosion rate of the alloys is increased by a magnetic field.

Ni-Cr alloyed layers were synthesized on the surface of Q235 mild steel by double-glow plasma surface metallurgy with different electrode distance. The microstructure and phases of the alloyed layer were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS), and X-ray diffraction (XRD). The corrosion behavior of the Ni-Cr alloyed layers both in 3.5% NaCl and 0.5 M H₂SO₄ solution were systematically investigated by open-circuit potential (OCP), potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The obtained results reveal that the Ni-Cr alloyed layer consists of a deposited layer and an inter-diffusion layer. With increasing the electrode distance, the relative thickness, microstructure and phase composition of the Ni-Cr alloyed layers vary greatly. Polarization data show the Ni-Cr alloyed layer with the electrode distance of 15 mm has highest corrosion resistance and lowest corrosion rate, while EIS results reveal the same trend. The highest protective efficiency in 3.5% NaCl and 0.5 M H₂SO₄ solution are 99.23% and 99.92%, respectively, obtained for the Ni-Cr alloyed layer with 15 mm electrode distance. When the electrode distance is too large, a thin and porosity Ni-Cr alloyed layer, caused by low plasma density and Kirkendall effect, will be obtained, and will decrease the protective efficiency in corrosive medium.

The corrosion behavior of Q370qNH steel in the presence and absence of hot-rolled oxide scale in simulated industrial atmospheric environment was studied by dry/wet cycle accelerated corrosion experiments. The experimental results show that the corrosion type of bare steel is uneven overall corrosion and large size pitting corrosion in small areas; that of oxide scale sample is local dissolution corrosion and small size pitting corrosion in large areas, and corrosion rate is much smaller than that of bare steel. The corrosion products of both steels are composed of α-FeOOH, γ-FeOOH, Fe₂O₃, and Fe₃O₄, but the formation mechanism is different. The bare steel generates α-FeOOH and γ-FeOOH through “acid regeneration cycle mechanism”; the oxide scale sample generates hydroxides mainly through the gradual dissolution of the oxide film, and then through “the acid regeneration cycle mechanism”. With the extension of corrosion time, the electrochemical stability of the sample with oxide scale increases, but the change of tafel curve of bare steel sample is not obvious. In simulated industrial atmosphere, the existence of hot-rolled oxide scale can facilitate the formation of dense rust layer on the surface of Q370qNH steel, which is more protective than bare steel.

The undercooled solidification microstructures of Cu55Ni45, Cu55Ni43Co2, and Cu60Ni38Co2 Cu-base alloys were obtained by fluxing method. Using infrared temperature measuring device, the law of the change of the recalescence degree with the increase of the undercooling during rapid solidification was studied. At the same time, high-speed camera was used to capture and photograph the images of solid/liquid interface migration during rapid solidification of undercooled melt, and the morphology evolution of solidification front was discussed. Finally, the microstructure morphology and transformation process of the Cu-based alloys were systematically analyzed. It is found that the microstructure morphology of the alloys goes through the same evolution process and appeared two grain refinement phenomena, that is, “coarse dendrite-equiaxed grain — oriented fine dendrite — equiaxed grain”. But its characteristics undercooling ΔT ₁, ΔT ₂, and critical undercooling ΔT* varies. Electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM) were used to characterize the grain refinement structure with high undercooling. EBSD results show that the grain refinement structure with high undercooling presents a very high proportion of high angle grain boundaries, the grain orientation is random and there is no high strength texture, and a large number of annealing twins, which indicates that recrystallization occurs in the structure. TEM results show that dislocation network and stacking fault density are relatively low in most areas of grain refinement structure with high undercooling, which can confirm the theory that stress induces recrystallization of the structure.

The isothermal compression tests of 7 085 aluminum alloy were carried out on Gleeble-3 800 thermal simulator by two-pass (30% per-pass) and three-pass (20% per-pass) at 300–400 °C and the strain rate of 0.01 s⁻¹. The effect of compression strategy on microstructure evolution of 7 085 aluminum alloy was analyzed by optical microscopy (OM) and electron backscattering diffraction (EBSD). The results show the softening mechanism of 7 085 aluminum alloy is mainly recovery, the recrystallization degree is sluggish when the samples deform at 300 °C. The fraction of recrystallized grains just reaches 23.2% at a higher deformation temperature of 400 °C, while a large amount of sub-grains with equiaxed morphology are formed inside the deformed grains. Different deformation paths have a significant effect on the microstructure evolution of the 7 085 aluminum alloys, and more uniform and fine microstructures are obtained at the three-pass deformation. In addition, a short holding time of 5 s is not enough to trigger the static recrystallization. When the holding time reaches 120 s, the dislocations rearrange and a large number of recrystallized grains and regular sub-grains appear inside the original grain. In a word, more uniform and fine microstructures are obtained at three-pass deformation at 400 °C and 120 s of 7 085 aluminum alloy.

The influence of carbon fiber reinforced plastic (CFRP) on dynamic mechanical properties of reinforced concrete (RC) beam was studied by drop hammer impact test system. The impact behaviors of beam, including failure mode, impact force peak value and peak deflection were analyzed. The experimental results show that bonding CFRP can reduce the crack width and change the failure mode of the beam. The length of CFRP has a certain influence on the impact force and deflection, and the peak inertia force of most beams is roughly in the range of 1/2-5/6 of the peak impact force. In addition, dynamic increase factor (DIF) increases with the increase of CFRP length, and its maximum value can reach 2.11.

The early-age hydration characteristics of composite binder containing graphite powder (GP) with two different finenesses were investigated by determining the hydration heat, thermo gravimetric, morphology of hardened paste as well as the compressive strength of mortar. The experimental results show that: replacing 2%–6% of cement with graphite powder significantly improves the piezoresistive effect of early age mortar, can be used to monitor accidental loads caused by dropped objects, collisions, or other accident events, and thus avoids initial damage. Some GP provides additional nucleation sites that lead to a fast formation of hydration products (nucleation-site effect). However, due to the almost hydrophobic water contact angle, most of the GP causes a large number of micro-cracks in the hydrated paste (gap effect). Because of the lamellar shape and high surface energy, GP is easily balled and can not be uniformly distributed in the composite, resulting in clumping together and wrapping some of the cement particles (barrier effect). Due to nucleation-site effect, when the dosages of coarse and fine GP reached 2% and 4%, 1 d strength were increased by 9.1% and 9.6%, respectively. At 3 days, as the interior damage caused by the gap effect gradually increased, and the retarding effect on cement hydration caused by barrier effect was enhanced. GP has an obvious negative effect on compressive strength. However, micro-cracks caused by fine GP are less, so its negative effect on 3 d compressive strength is lower.

A lead-free base glaze suitable for pearlescent pigments was prepared by a low-temperature solid-phase reaction with alkali waste. Tests were performed to evaluate the effects of the sintering conditions and alkali waste composition on the prepared base glaze and pearlescent glaze. The experimental results show that partially replacing SiO₂ with B₂O₃ effectively reduced the sintering temperature and time to form a glass network, but the network structure becomes disconnected as the B₂O₃ content increases. An amorphous base glaze was obtained when soda ash was replaced with a small amount of alkali waste, but increasing the addition of NaCl further was adverse to base glaze formation by resulting in crystallization of the base glaze and a decrease in the bridging oxygen content. The pearlescent pigment was thermally stable in the glaze at 750 °C, while higher temperatures caused the crystalline phase of NaAlSiO₄ to appear and adhere to the surface of pigment granules, which degraded the pearlescent effect of the glaze.

Keratinocytes and fibroblasts, derived from hiPSCs, were used to construct the human epidermal model by a culture patch made by monolayer poly-(lactic-co-glycolic acid) (PLGA) nanofibers and a human skin-on-a-chip device. Unlike the conventional culture dish method, two different epidermal cells are successfully adhered to the front and back sides of the patch, which produces a three-dimensional nanofibrous scaffold similar to a natural extracellular matrix before the patch was cultured in the skin-on-a-chip device to mimic the physiological conditions of human skin. As expected, the differentiated hiPSCs show the expression of keratinocyte- and fibroblast- specific proteins on the patch, and the layering is found between these two kinds of cells, indicating that this approach creates a powerful in vitro system for modeling skin development and diseases.