A one-step ultrasonic mechanical method was used to synthesize a kind of atmospheric water harvesting material with high water harvesting performance in a wide relative humidity (RH) range, especially at low RH (RH < 40%), namely, mesoporous silica capsule (MSC) with core-shell structure. Transmission electron microscopy (TEM), nitrogen adsorption and other characterization techniques were used to study the formation process of nano-microspheres. A new mechanism of self-adaptive concentration gradient regulation of silicon migration and recombination core-shell structure was proposed to explain the formation of a cavity in the MSC system. The core-shell design can enhance the specific surface area and pore volume while maintaining the monodispersity and mesoporous size. To study the water harvesting performance of MSC, solid silica nanoparticles (SSN) and mesoporous silica nanoparticles (MSN) were prepared. In a small atmospheric water collection test (25 °C, 40% RH), the water vapour adsorption and desorption kinetics of MSC, SSN, MSN and a commercial silica gel (CSG) were compared and analyzed. The results show that the MSC with mesoporous channels and core-shell structure can provide about 0.324 g _water/g _adsorbent, 79% higher than the CSG(0.181 g _water /g _adsorbent). It is 25.1% higher than that of 0.259 g _water /g _adsorbent of un-hollowed MSN and 980% higher than that of 0.03 g _water /g _adsorbent of un-hollowed SSN. The material has a large specific surface area and pore volume, simple preparation method and low cost, which provides a feasible idea for realising atmospheric water collection in arid and semi-arid regions.

B₂O₃-ZnO-SiO₂(BZS) glass containing CuO with excellent acid resistance, wetting properties, and high-temperature sintering density was prepared by high temperature melting method and then applied in copper terminal electrode for multilayer ceramic capacitors (MLCC) applications. The structure and property characterization of B₂O₃-ZnO-SiO₂ glass, including X-ray diffraction, FTIR, scanning electron microscopy, high-temperature microscopy, and differential scanning calorimetry, indicated that the addition of CuO improved the glass’s acid resistance and glass-forming ability. The wettability and acid resistance of this glass were found to be excellent when CuO content was 1.50 wt%. Compared to BZS glass, the CuO-added glass exhibited excellent wettability to copper powder and corrosion resistance to the plating solution. The sintered copper electrode films prepared using the glass with CuO addition had better densification and lower sintering temperature of 750 °C. Further analysis of the sintering mechanism reveals that the flowability and wettability of the glass significantly impact the sintering densification of the copper terminal electrodes.

Ion implantation induced damage in GaSb and its removal by rapid thermal annealing (RTA) have been investigated by Raman spectroscopy. The evolution of the Raman modes as a function of implantation fluence, annealing temperature and time has been analyzed. Results indicate that a lattice quality that is close to as-grown GaSb has been obtained by annealing the implanted samples at 500 °C for 45 s. However, consequent surface analyses by scanning electron microscope (SEM) and atomic force microscope (AFM) show that a heavily perturbed layer contains voids due to the outdiffusion of Sb atoms on the surface remains. Mechanism of the damage recovery and the structure of the implanted layer are discussed based on the experimental results.

The duck eggshell waste was developed to the novel desiccant that is friendly to human and environment. The calcium oxide (CaO) and calcium chloride (CaCl₂) as the calcium-based desiccants were prepared from eggshell waste. The CaO desiccant derived from the eggshell waste sintering at 1 300 °C, while the CaCl₂ desiccant was extracted from eggshell waste with the hydrochloric (HCl) solution at different concentrations from 5 to 30 wt%. The yield percentage of CaCl₂ desiccant increased with increasing the HCl concentration to 25 wt%. The humidity adsorption behavior were investigated in the range of 75%–5% relative humidity. The results show the CaCl₂ desiccant has the highest hydration rate. The porous host from the kaolin was sintered at different temperatures from 200 to 1 000 C and incorporated with 30%w/v concentrations of CaCl₂. The physical properties and the humid-adsorption capacity of all porous host conditions were investigated. The porous host at sintering temperature 800 °C has the highest specific surface area. Moreover. the porous host at sintering temperature 800 °C with the 30%w/v concentration of CaCl₂ desiccant has the highest humid-adsorption capacity.

Co(_1−x)Zn _xFe₂O₄ nanospheres (x = 0, 0.5, 0.8) with a unidirectional cubic spinel structure were prepared by a solvothermal method. By using a range of theoretical and empirical models, the experimental heat capacity values were fitted as a function of temperature over a suitable temperature range to explain the possible relationship between the magnetic properties and microstructure of the nanospheres. As a result, at a low temperature (T < 10 K), the parameter B _fsw decreases with increasing Zn concentration, implying that the exchange interaction between A and B sites decreases. At a relatively high temperature (T > 50 K), the Debye temperature decreases with increasing Zn concentration, which is due to the weakening of the interatomic bonding force after the addition of non-magnetic materials to the CoFe₂O₄ spinel ferrite.

The Bi₂MoO₆/TiO₂ and Bi₂MoO₆/Ag/TiO₂ composites were solvothermally synthesized and characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and (high resolution) transmission electron microscopy ((HR)TEM). The Bi₂MoO₆/TiO₂ and Bi₂MoO₆/Ag/TiO₂ composites exhibited higher photocatalytic activity than pure Bi₂MoO₆. 100% of the RhB dye molecules could be decomposed over Bi₂MoO₆/Ag/TiO₂ composite in 120 min. The enhanced photocatalytic activity of Bi₂MoO₆/TiO₂ and Bi₂MoO₆/Ag/TiO₂ composite was attributed to the efficient separation of photoinduced electrons and holes. The mechanism for the enhanced photocatalytic activity is discussed.

Fe₃O₄ and Cu₂O were successively immobilized on alkali-treated straw, and the magnetically separable straw@Fe₃O₄/Cu₂O composite was obtained. The straw@Fe₃O₄/Cu₂O was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy and vibrating sample magnetometry, respectively. Photocatalytic performance of the straw@Fe₃O₄/Cu₂O was evaluated by measuring the degradation of methyl orange (MO) under irradiation of visible light. The introduction of Fe₃O₄ not only endowed the straw@Fe₃O₄/Cu₂O with magnetic separation feature but also significantly enhanced photocatalytic activity because Fe₃O₄ could prevent recombination of hole-electron pairs. The active species capture experiment showed that holes (h⁺), hydroxyl (·OH) and superoxide (·O₂ ⁻) radicals all took part in the MO degradation. In addition, the photocatalytic mechanism of straw@Fe₃O₄/Cu₂O was proposed based on the experimental results. After five cycles for the photodegradation of MO, the straw@Fe₃O₄/Cu₂O still displayed good photocatalytic activity, suggesting that the as-prepared composite had great potential for practical use in wastewater treatment.

The well-developed particle-swarm optimization method together with density functional theory calculations were employed to search lowest-energy geometric structures of two-dimensional (2D) SiGeP₂. Two newly found structures (P3m1 and Pmm2) are predicted. The unbiased global search reveals that the two lowest-energy structures are honeycomb lattices with robust dynamical stabilities. A more accurate Heyd-Scuseria-Ernzerhof (HSE06) hybrid functional is used to estimate the band structures of SiGeP₂, which indicates that both the structures are semiconductors with indirect band-gap energies 1.80 eV for P3m1 and 1.93 eV for Pmm2, respectively. Using the deformation potential theory, the P3m1-SiGeP₂ is predicted to have high electron mobilities (6.4×10⁴ along zigzag direction and 2.9×10³ cm²·V⁻¹·s⁻¹ along armchair direction, respectively) and hole electron mobilities (1.0×10³ along zigzag direction and 2.5×10³ cm²·V⁻¹·s⁻¹ along armchair direction, respectively), which can be comparable with that of phosphorene and show anisotropic character in-plane. In addition, to estimate the elastic limit of SiGeP₂, we also calculated the surface tension of SiGeP₂ as a function of tensile strain. Our results show that the 2D SiGeP₂ may be good candidaticates for applications in nanoelectronic devices.

We investigated the mixed alkali effect on the thermal properties and elastic response to temperature in the borosilicate glasses system with the composition of 70.65SiO₂·21.09B₂O₃·1.88Al₂O₃·(6.3 8− x)Li₂O·xNa₂O glasses, where x = 0.00, 1.595, 3.19, 4.785, and 6.38. Except for the expected positive and negative deviations from linearity for the coefficients of thermal expansion, room temperature E and G, we observed a new mixed alkali effect on the response of elastic moduli to temperature. Fourier transform infrared spectra were obtained to elucidate the possible structural origin of the mixed alkali effects. This work provides a valuable insight into the structural and mechanical properties of mixed-alkali borosilicate glasses.

AlN ceramics were prepared by plasma activation sintering (PAS) with compound additives yttrium acetylacetonate (Y(acac)₃) and melamine (C₃H₆N₆). The effects of compound additives on the microstructure, density, and thermal properties of AlN ceramic were studied. Y(acac)₃ and C₃H₆N₆ can form Y₂O₃, residual organic carbon and reducing gas during the heating process, which improves the AlN sintering performance at a temperature of 1 700 °C and the bulk thermal conductivity. When the content of Y(acac)₃ is 10 wt% and C₃H₆N₆ is 3 wt%, the thermal conductivity of AlN ceramics is 105.6 W/(m·K), which is much higher than that of AlN ceramics with Y₂O₃ under the same sintering conditions. This work provides theoretical reference for the preparation of high-performance AlN ceramic.

Split Hopkinson pressure bar (SHPB) was used to investigate the dynamic compressive properties of sisal fiber reinforced coral aggregate concrete (SFCAC). The results showed that, with the increase of strain rate, the dynamic compressive strength, peak strain and toughness index of SFCAC are all greater than its static properties, indicating that SFCAC is a kind of rate-sensitive material. When the sisal fiber was blended, the failure mode showed obvious ductility. At high strain rates, the SFCAC without sisal fiber specimen was comminuted, and the SFCAC showed a “cracked without breaking” state. The results indicated that the sisal fiber played a significant role in reinforcing and strengthening the properties of concrete. The finite element software LS-DYNA was used to simulate two working conditions with strain rates of 78 and 101 s⁻¹. The stressstrain curves and failure patterns obtained were in good agreement with the experimental results.

This research proposes a new pixel-based model called the hydration-pixel probability model which aims to simplify cement hydration as a probability problem. The hydration capacity of cement, the solution within pores, and the diffusion of solid particles are represented by three probability functions derived from experimental data obtained through electrical resistivity and hydration heat measurements. The principle of the model is relatively simple, and the parameters have clear physical meanings. In this research, the porous structures of different cement pastes with w/c ratios of 0.3, 0.4, and 0.5 are investigated. The results indicate that the porosity of the cement paste decreases during the first few hours, followed by a rapid decline, and eventually reaches a steady state. The porosity of the paste decreases as w/c ratio decreases, and the rate of decrease is more rapid in the early stages. Referring to the porosity curves, the average degree of hydration and depth of hydration can be derived. The simulation results show that the hydration degree of paste composed of irregular particles is higher than that of the paste composed of round particles. The trend in the development of the average hydration depth is similar to that of the average hydration degree. Upon analyzing the average growth rate of the hydration depth, it is observed that there are two peaks in the curves, which correspond to the three characteristic points in the electrical resistivity test.

To solve the cryogenic temperature problems faced by all-concrete liquefied natural gas (ACLNG) storage tanks during servicing, a low temperature resistant and high strength concrete (LHC) was designed from the perspectives of reducing water-binder ratio, removing coarse aggregates, optimizing composite mineral admixture and utilizing steel fibers. The variation laws of compressive and tensile strength, elastic modulus and Poisson’s ratio for C60 concrete and LHC were compared and analyzed under the temperatures from 10 to −165 °C through uniaxial compression and tensile tests. The rapid freezing method was adopted to analyze the evolution process of mass and relative dynamic elastic modulus loss rates for C60 and LHC in 0–300 freeze-thaw cycles. The gas permeability test was carried out, and the laws of gas permeability coefficient varied with temperature and cryogenic freeze-thaw cycles were obtained. Then, the grey dynamic model GM (1,1) was used to predict the variation laws of physical and mechanical parameters on the basis of the test data. The test results demonstrate that the compressive strength, elastic modulus and Poisson’s ratio for both C60 and LHC increase significantly from 10 to −165 °C, but the specific variation laws are different, and there is a phenomenon that some parameters decrease after reaching a critical temperature range for C60. The uniaxial tensile strength increases first and then decreases as temperature decreases, and finally increases slightly at −165 °C for both C60 and LHC. The mass and relative dynamic elastic modulus loss rates of LHC are much lower than that of C60 under different freeze-thaw cycles. The gas permeability coefficient of C60 declines gradually with the drop of temperature, and increases gradually with the number of freeze-thaw cycles while the gas permeability coefficient of LHC basically remains stable and is much lower than that of C60. Therefore, such a conclusion can be drawn that LHC has better properties at cryogenic temperature. On the premise of providing consistent functional mode, GM (1,1) can predict the test data with high accuracy, which well reflects the variation laws of relevant parameters.

We investigated the effects of ferro-vanadium slag (FVS) as a supplemental cementing material which can dissolve a large amount of active aluminum phases without excessive pretreatment or excitation to enhance the inner chloride solidified rate (CSR) of cement-based materials. Cement-FVS pastes with 0–30% content of FVS was designed, and the CSR was examined. Hydrates at different curing ages were studied by X-ray diffraction (XRD) and thermo-gravimetric analysis (TGA); hydration heat and ²⁹Si nuclear magnetic resonance (²⁹Si-NMR) were tested to analyze the hydration degree of the system; mechanical properties in cement-FVS system were evaluated by compressive strength test, pore structure and the fractal regression. Results revealed that the incorporation of FVS could greatly promote the CSR of cement-FVS system. Compared with the control groups, 30% dosage of FVS could increase the CSR by 69% at 3 d, 47% at 7 d, 36% at 28 d and 34% at 60 d. It was demonstrated that the incorporation of FVS could enhance the chemical solidifying ability of chloride, and the main reason was the promoted generation of Kuzel’s salt and the Friedel’s salt in hydrate products, and the enhanced chloride migration resistance capacity by increasing the volume of gel pores in the cement-FVS system. Considering the influence of FVS on strength performance, this paper suggested that the suitable dosage of FVS as a supplemental cementing material was around 10%. The study in this paper might provide one efficient path to promote the chloride solidifying capacity of cement-based material and meanwhile the comprehensive utilization of FVS.

This study aims to investigate the behavior of alkali activated mortar, which is made of naturally available magnesium silicate as source material. For magnesium silicate, ultrafine natural steatite powder (UFNSP) is used as the primary source of binder, and the activation is initiated through the alkali liquid which is proportioned in various combinations of silicate to hydroxide ratio (Na₂SiO₃/NaOH) ratio, and this ratio in this study varies from 1 to 3. The UFNSP is calcined at two different temperatures, 700 and 1 000 °C. The mortar mix is proportioned as 1:3 between powder and the fine aggregate, and the mortar is prepared with hydroxide molarity (M) of 10 M. The mortar is cured for 48 hours at 60 °C and the compressive strength was studied. All the mix were studied for its microstructural behavior along with compressive strength. The mix proportion of the mortar, and the results obtained through microstructural characterization were combinedly formed as input for artificial neural network(ANN) predictive modelling. The model is designed to predict the compressive strength, which is trained through Bayesian regularization algorithm with varying hidden neurons of 7 to 10. This experimental and predictive study shows that the strength is influenced by both Na₂SiO₃/NaOH ratio and calcination process. And the ANN is influenced by mainly calcination temperature and uncorrelation occurs in selected samples of 1 000 °C calcined UFNSP mix.

Basic magnesium sulfate cement coral aggregate concrete (MCAC) is a new type of concrete consisting of basic magnesium sulfate cement, coarse coral aggregate, coral reef sand and seawater. The rebound hammer (RH), the ultrasonic pulse velocity (UPV) and the compressive strength (f _cu) tests of 14 sets of cube specimens of the MCAC after 28 d of aging were conducted. The impact of the content and length of sisal fiber on the relationship between the fcu - RH and the fcu - UPV was determined. A mathematical model was established to predict the strength of the MCAC using the UPV, RH, and comprehensive UPV/RH methods and to obtain the curves of test strength. The applicability of the test strength curves of ordinary portland concrete (OPC), light-weight aggregate concrete (LAC), and coral aggregate concrete (CAC) to MCAC was assessed. The results showed that the test strength curves of OPC, LAC and CAC were inappropriate to determine the strength of MCAC using non-destructive method. The relative standard error of the curves of test strength of the RH method and the comprehensive method met the specifications, whereas that of the UPV method did not.

In order to evaluate the feasibility of steel slag powder as filler, the coating properties of steel slag and limestone aggregate were compared by water boiling test, the micro morphology differences between steel slag powder and mineral powder (limestone powder) were compared by scanning electron microscope (SEM), and the high-temperature rheological properties of asphalt mortar with different ratio of filler quality to asphalt quality (F/A) and different substitution rates of mineral powder (S/F) were studied by dynamic shear rheological test. The results show that the surface microstructure of steel slag powder is more abundant than that of mineral powder, and the adhesion of steel slag to asphalt is better than that of limestone. At the same temperature, the lower the ratio of S/F is, the greater the rutting factor and complex modulus will be. In addition, the complex modulus and rutting factor of the asphalt mortar increase with the increase of F/A, and the filler type and F/A have a negligible effect on the phase angle.

The effect of an innovative accelerated carbonation curing technique was evaluated on concrete containing natural zeolite powder and fine aggregate as partial replacement to alleviate the CO₂ emission up to a certain extent from the concrete production industry and improve sequestration of CO₂ into the concrete matrix in a stable form. An accelerated carbonation curing was accomplished by subjecting the concrete specimens to 0.5 and 0.75 M concentrations of sodium bicarbonate (NaHCO₃) solutions up to a curing age of 180 days after the initial 28 days of normal water curing. Tests for carbonation depth, pH value, compressive strength, calcium carbonate (CaCO₃) content, X-ray diffraction, and thermogravimetric (TGA) analyses and Fourier transform infrared spectroscopy (FTIR) were performed to measure the extent of carbonation. The obtained results showed an increment in average compressive strength for the zeolite concrete (ZLC) mixes exposed to accelerated carbonation curing. The ZLC mixes exposed to increasing NaHCO₃ solution concentration and exposure period exhibited greater carbonation depth and decreased pH at each depth interval indicating higher CO₂ sequestration within the concrete matrix. The results obtained from the microstructural analysis (XRD, TGA, and FTIR) and CaCO₃ content measurements confirm that the higher amount of CaCO₃ formation provides a clear indication of the carbonation enhancement and CO₂ sequestration within the concrete matrix and in turn contributing to the global warming reduction.

This study aims to investigate the effect of the mesoscopic characteristics of mineral powder fillers on the rutting resistance of asphalt mortar. Extraction and sieving tests were used to obtain the buton rock asphalt (BRA) ash with particle size smaller than 0.075 mm, which is consistent with that of the conventional mineral powder. The mesoscopic characteristics of BRA ash and conventional mineral powder were measured by SEM image analysis and the osmotic free pressure water method. Mesoscopic structure models of structural and free asphalts in mortar were obtained. The 70# matrix asphalt was used to prepare two kinds of asphalt mortar with BRA ash and conventional mineral powders fillers. The rutting factor of the two asphalt mortars was tested by dynamic shear test (DSR). Test results show that the ash extracted from BRA has a similar mesoscopic classification with the conventional mineral powder. Still, its fractal dimensions are larger, indicating the particles in BRA ash have more complex shapes and rougher surfaces, which is beneficial for forming structural asphalt and subsequently increasing the rutting factor (G*/sinδ), i e, improving the rutting resistance of the asphalt mortar.

To develop the microwave absorbing (MA) properties of cementitious material mixed with mine solid waste, the iron tailings cementitious microwave absorbing materials were prepared. The iron tailings was treated into different particle sizes by planetary ball mill, and the physicochemical properties of iron tailings were tested by laser particle size analyzer and scanning electron microscope (SEM). The electromagnetic parameters of iron tailings cementitious materials were characterized by a vector network analyzer and simulated MA properties, and the MA properties of iron tailings-cement composite system with steel fiber as absorber was studied. Based on the design of the single-layer structure, optimum mix ratio and thickness configuration method of double-layer structure were further studied, meanwhile, the mechanical properties and engineering application were analyzed and discussed. The results show that the particle size of iron tailings can affect its electromagnetic behavior in cementitious materials, and the smaller particles lead the increase of demagnetisation effect induced by domain wall motion and achieve better microwave absorbing properties in cementitious materials. When the thickness of matching layer and absorbing layer is 5 mm, the optimized microwave absorbing properties of C1/C3 double-layer cementitious material can obtain optimal RL value of −27.61 dB and effective absorbing bandwidth of 0.97 GHz, which attributes to the synergistic effect of impedance matching and attenuation characteristics. The double-layer microwave absorbing materials obtain excellent absorbing properties and show great design flexibility and diversity, which can be used as a suitable candidate for the preparation of favorable microwave absorbing cementitious materials.

A magnetically filtered cathode vacuum arc deposition system was used to deposit Ti-doped diamond-like carbon coatings (Ti-DLC) on pin surfaces to improve the wear resistance of high-power density diesel engine piston pins. The coating structure, composition, and morphology were characterised using field emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and other techniques. Friction tests were carried out using a universal tribometer to study the tribological properties of pins with or without coatings under dry friction and oil lubrication. The surface morphology and cross-sectional morphology of the Ti-DLC coating show that the coating has a uniform cross-section and good surface properties. The XPS spectrum shows that the coating contains Ti-C, Ti-C*, sp2-C, sp3-C, and C-O/C=O. Raman spectroscopy shows that there is an amorphous carbon phase in the Ti-DLC coating. The friction test shows that the friction temperature increase of the pin with the Ti-DLC coating is lower than that without the coating, especially under dry-friction conditions. At the end of the test, the difference in temperature increase is 16.7%. The friction coefficient when using high-viscosity lubricating oil with a coating is relatively lower than that without a coating, especially under low-speed and heavy-duty conditions. In the dry-friction state, the coated surface has better wear resistance than the uncoated surface, which primarily manifests as abrasive wear, and the surface without a coating mainly experiences adhesive wear.

Split sleeve cold expansion (SSCX) can effectively enhance fatigue life of holes by improving the field of residual stress. Numerical simulations were conducted to investigate the parameter influence mechanism and obtain higher compressive residual stress (CRS). Expansion method, degree of cold expansion (DCE), friction coefficient between laminations and depth-diameter ratio were analyzed. For Ti-Al stacked joint holes, two expansion methods are proposed, namely aluminum alloy first followed titanium alloy (Al first) and titanium alloy first followed aluminum alloy (Ti first). The results show that expansion method and DCE have significant effects on the field of circumferential residual stress, and the friction has a negligible influence. A higher value of CRS and a wider layer of plastic deformation are induced with Ti first. Optimal DCE of Ti-Al stacked structure is 5.2%–5.6%. As the depth-diameter ratio is in the range of 0.5–1.25, a positive linear correlation between the maximum compressive residual stress (CRS_max) and depth-diameter ratio is shown.

Dense zirconium coatings on copper substrates were obtained in an alumina crucible and a stainless steel crucible from FLiNaK-K₂ZrF₆ molten salt at 1 023 K. Due to the potential differences between copper and zirconium, zirconium can diffuse into the copper substrate to form zirconium alloys on the surface of copper substrates in the course of deposition. The coating deposited in a stainless steel crucible has a gray surface. The components of the coating are mainly CuZr₂ alloy and Cu₁₀Zr₇ alloy, and, the outermost layer of the coating is a layer of amorphous pure zirconium. The coating deposited in an alumina crucible has a silvery white metallic luster. The components of the coating are mainly Cu-Zr-Al intermetallic compounds, AlCu₂Zr, ZrAl, AlCu and CuZr. Furthermore, two types of zirconium coatings can greatly increase the hardness of the substrate.

The influences of adding different amount of Ti (0%, 0.39%, 0.87%) and three kinds of different aging processes (T6, T6I6, RRA) on the microstructure and properties of Al-11.3Zn-3.2Mg-1.3Cu-0.2Zr-0.1Sr were investigated. Results show that an appropriate amount of Ti can effectively inhibit grain growth and thus achieve the effect of grain refinement. The contribution of dislocation density and dislocation strengthening become the biggest when Ti content is 0.39%. At the same time, the intergranular corrosion depth is the lowest when Ti content is 0.39%. Among the three aging processes, the alloys reach the greatest hardness and tensile strength in T6I6. The biggest tensile strength reaches 716.77 MPa. However, when aging at RRA, the alloys obtain the greatest elongation, reaching 7.2%, as well as the good corrosion resistance.

The ultra-fine grained (UFG) pure titanium was prepared by equal channel angular pressing (ECAP) and rotary swaging (RS). The strain controlled low cycle fatigue (LCF) test was carried out at room temperature. The fatigue life prediction model and mean stress relaxation model under asymmetrical stress load were discussed. The results show that the strain ratio has a significant effect on the low cycle fatigue performance of the UFG pure titanium, and the traditional Manson-coffin model can not accurately predict the fatigue life under asymmetric stress load. Therefore, the SWT mean stress correction model and three-parameter power curve model are proposed, and the test results are verified. The final research shows that the three-parameter power surface model has better representation. By studying the mean stress relaxation phenomenon under the condition of R≠−1 it is revealed that the stress ratio and the strain amplitude are the factors that significantly affect the mean stress relaxation rate, and the mean stress relaxation model with the two variables is calculated to describe the mean stress relaxation phenomenon of the UFG pure titanium under different strain ratios. The fracture morphology of the samples was observed by SEM, and it was concluded that the final fracture zone of the fatigue fracture of the UFG pure titanium was a mixture of ductile fracture and quasi cleavage fracture. The toughness of the material increases with the increase of strain ratio at the same strain amplitude.

A novel micro fused-casting (MFC) process is developed for semisolid aluminum alloy slurry. The microstructure evolution and properties of semisolid ZL101 aluminum alloy slurry with different pouring temperature by MFC are investigated in this paper. During the cooling process, the effects of the pouring temperature on microstructure and properties is primarily analyzed. The microstructure of the semisolid ZL101 aluminum alloy is more homogeneous and the grain is smaller under proper pouring temperature. Temperature of liquids and solids of ZL101 aluminum alloy is measured by differential scanning calorimetry (DSC). Distribution and characteristics of the microstructure of samples are examined by optical microscope (OM), scanning electron microscopy (SEM) equipped with energy dispersive spectrometer (EDS). The results show that the ZL101 semisolid slurry fabricated by MFC presents uniform shape and good grain size under the pouring temperature of 594 °C and the stirring velocity of 600 r/min, and the fine grains of the primary α-Al phase with average grain size of 55 μm and shape factor up to 0.67 were obtained. Besides, the ultimate tensile strength and the average Vickers hardness for semisolid ZL101 aluminum slurry are 178.19±1.37 MPa and 86.15±1.16 HV, respectively.

We devoloped an efficient and simple method to synthesize fluorene derivatives via intramolecular Friedel-Crafts alkylation of chalcones. The transform is catalyzed by TfOH in CH₃NO₂ at 80 °C and the yield is up to 99%.

In order to improve the mechanical properties and thermal conductivity of polymethyl methacrylate (PMMA), multi-walled carbon nanotubes (MWCNTs) were used as reinforcement through in situ polymerization method to prepare PMMA/MWCNTs composites by changing the reaction time, polymerization temperature and the content of MWCNTs. The effects of different reaction conditions on the properties of the composites were studied. The results show that the mechanical properties, thermal/electrical conductivity and thermal stability of the composites are improved compared with the PMMA matrix. The tensile strength of the composites is increased by up to 24%. The bending strength of the composite material increases from 20.41 to 68.04 MPa, and the maximum increase is 233%. Meanwhile, when the content of MWCNTs is 3 wt%, the thermal conductivity of the composite is 0.335 W/(m-K), which increases by 138%, and the electrical conductivity is 3.94 S/m. The thermal stability of the composite has been significantly enhanced. The modified PMMA will be widely used in medicine, communications, electronics and other fields.

We investigated the removal of the organic dye rhodamine B in wastewater with recyclable AgBr/polypyrrole (PPy) nano-photocatalysts. With PPy as an active base for electron transfer, and hexadecyltrimethylammonium bromide (CTAB) as both the soft-templating agent and the bromine source, a series of AgBr/PPy nano-photocatalysts containing various proportions of silver were prepared in a convenient one-step synthesis procedure. The synthesized catalysts were characterized by TG analysis to reveal that, in comparison with pure PPy, the interaction between PPy and AgBr led to increased thermal stability. Chemical combination of PPy and AgBr was observed through XRD and XPS analyses. For the morphology study, the AgBr particles were found to be well dispersed in the PPy nanowire network from SEM results. In the photodegradation experiments, up to 92% rhodamine B was degraded by the AgBr/PPy catalysts in the period of 1 hour under 254 nm UV light. The catalysts could maintain 60% catalytic efficiency after 3 cycles in the recyclability test.

The work is dedicated to develop a one-step eco-friendly method to prepare antibacterial polyethylene terephthalate (PET). We report a one-step eco-friendly method to manufacture antibacterial PET via on-line amination reaction by melt coextrusion. Beside evenly mixing of poly(hexamethylene guanidine) (PHMG) and PET in the melt coextrusion procedure, the amination reaction also occurred between PHMG and PET under high temperature (230–270 °C). The antibacterial ability of composite PET showed obvious PHMG concentration dependence, and antibacterial activity reached more than 99% when PHMG content was 2.5 wt%. Moreover, LIVE/DEAD fluorescence test further confirmed that the composite PET could kill bacteria quickly and effectively (within 30 min); while negligible cytotoxicity was observed to HSF and HUVEC cells. One-step eco-friendly fabrication of composite antibacterial PET was accomplished by on-line melt coextrusion. The composite antibacterial PET has potential use in multiple fields to combat with pathogenic including textiles, packaging materials, decoration materials and biomedical devices, etc.

K-struvite was prepared by precipitation method, and the stability of K-struvite in high temperature and acid-base environment were investigated by X-ray diffraction (XRD), thermogravimetric analysis (TG/DSC), and infrared spectroscopy (FT-IR). The results show that K-struvite decomposes from 50 to 110 °C, and the mass loss begins at 50 °C before being completely destroyed at 110 °C, then further heating at temperature above 500 °C leading to complete loss of the binding water in K-struvite. Moreover, K-struvite is more stable in alkaline environments than acidic environment.

The low-valence cations Na⁺ and Sr²+ were selected as the co-dopants to increase the vacancies concentration in the Y_2.982Ce_0.018Al₂Ga₃O₁₂ phosphor. The successful incorporation of Na⁺ and Sr²⁺ was confirmed by the X-Ray Diffraction (XRD) results. All the samples show 5d-4f green persistent luminescence of Ce³⁺ after 450 nm excitation. The decay curves demonstrate that the persistent luminescence is effectively enhanced with Na⁺ and Sr²⁺ doping. The thermoluminescence glow curves also show not only does the trap concentration increase, but also the distribution of trap depths is broadened. In addition, the air- and H₂/Ar-annealing treatments were conducted on every as-made sample. The experimental results prove that the increased traps after the Na⁺/Sr²⁺ doping are mainly attributed to the oxygen vacancies, and the traps have a continuous and broad distribution of trap depths. We hope this work could give new inspiration for designing a high-performance persistent phosphor.