Along with the long preparation cycle time and high cost of conventional preparation methods, the inherent high thermal conductivity of TiCoSb Half-Heusler alloy limited its commercial application. Herein, Ti_1-xNb_xCoSb Half-Heusler alloys with low thermal conductivity were successfully prepared by microwave synthesis combined with rapid hot-pressing sintering, which substantially shortened the preparation cycle and increased the density of TiCoSb Half-Heusler alloys. Furthermore, we studied the effects of Nb substitution at Ti sites on the phase composition, composition distribution, and thermoelectric transport properties of Ti_1-xNb_x CoSb Half-Heusler thermoelectric materials. Additionally, the figure of merit(ZT) of Ti_1-xNb_x CoSb samples were considerably optimized under the combined effects of increasing power factor and decreasing lattice thermal conductivity. The results showed that the Ti_0.93Nb_0.07CoSb sample had a maximum ZT of 0.1 at 725 K, which was two orders of magnitude higher than that of the TiCoSb sample prepared by the same process.

In this paper, graphene prepared by liquid-phase stripping assisted by tannic acid achieved better dispersion than ordinary graphene. The new graphene can meet the requirements of low cost, high output, and environmental protection. Graphene-SiO₂ hybrid materials were obtained by reacting SiO₂ treated with silane coupling agent (KH550) modification and graphene modified with tannic acid to form strong hybridization bonds, and the success of obtaining graphene-SiO₂ hybrid materials was confirmed by infrared spectroscopy. Furthermore, the mechanical properties of graphene-SiO₂ hybrid material in styrene-butadiene/polybutadiene composites were studied. In addition, the mechanical properties and the electrical and thermal conductivity of the blend of conductive carbon black and graphene-SiO₂ hybrid material in styrene-butadiene/polybutadiene composite were investigated. The results show that: at the addition of 1 part per hundred(phr) of graphene-SiO₂ hybrid material, the butadiene/cis rubber composites obtained relatively good wear resistance, if the loading is more than 1 phr, the graphene fillers will easily reaggregate with each other, resulting in an increase in wear volume compared with the blank control group. Moreover, when 8 phrs of self-made graphene were added, the conductivity increased by 1 000 times, and the antistatic properties of rubber composites were considerably improved.

Silica (mainly comprising nano-SiO₂) is widely used in rubber reinforcement owing to its advantages of easy preparation and environmental protection. However, owing to its structural characteristics, silica has poorer dispersion and reinforcement ability than carbon black. The purpose of this paper is to present a proposal to improve the dispersion of silica in rubber using a silane coupling agent and to study the effect of synergistic reinforcement of modified silica and graphene on natural rubber. The hybrid filler KS-TGE was obtained through a Michael addition reaction between graphene modified by dispersant tannic acid and silica (KS) modified by the silane coupling agent KH570. Subsequently, the KS-TGE/NR composites were prepared by mixing KS-TGE with natural rubber. Test results showed that the modified silica improves the dispersion in rubber and the mechanical properties of natural rubber after blending with the hybrid filler prepared using graphene and natural rubber. Compared with unmodified nano-SiO₂/NR, the tensile strength of the modified composites increased by 36.3% and the elongation at break increased by 79.5%. In addition, KS-TGE/NR can maintain excellent elastic and dynamic mechanical properties.

In this paper, the preparation process of N-propylethylenediamine bonded silica gel (PSA) with controllable bonding amount was optimized; the batch repeatability of PSA preparation was examined; and the pilot scale-up experiment of PSA preparation was conducted. The properties of the PSA were investigated by infrared spectroscopy, elemental analysis, and potentiometric titration. The results showed that N—H stretching vibration peaks appeared at 3 460 cm^-1, asymmetric and symmetric stretching vibration peaks of —CH appeared at 2 960 cm^-1 and 2 860 cm^-1, and deformation vibration absorption peaks of —NH₂ appeared at 708 cm^-1, indicating that N-propylethylenediamine was successfully grafted onto the surface of silica gel.Furthermore, with the increasing proportion of silane reagent in the preparation system, the content of carbon, nitrogen, and hydrogen elements and the ion exchange capacity obtained by potentiometric titration showed an upward trend, indicating that the bonding amount of ethylenediamine-N-propyl functional group gradually increased. Moreover, the prepared PSA packing component was separated from the purification column, and the removal efficiency of ginkgolic acid from the extract of ginkgo biloba leaves using PSA with different bonding amounts was investigated. The results showed that PSA had a strong adsorption capacity for ginkgolic acid and could be used to remove ginkgolic acid from the extract of ginkgo biloba leaves, the maximum sample loading volumes for PSA separation and purification columns 2^#, 3^#, 4^#, and 5^# are 21, 22, 23, 24 mL, respectively. In addition, the removal efficiency was found to increase with the increasing amount of ethylenediamine-N-propyl bonding.

Polyvinyl chloride (PVC) foam board is prepared by extrusion foaming of PVC with low polymerization degree, and the PVC foam board is prone to curling movement along the force direction of the molecular chain due to environmental changes, resulting in shrinkage and deformation of the board. Heavy calcium carbonate (HCC) was used as raw material, polyvinyl alcohol (PVA) and tannic acid (TA) were used as modifiers to prepare modified HCC. It was combined with PVC to prepare PVC foam sheets. Infrared spectrometer, differential scanning calorimeter, scanning electron microscope, Vicat softening point tester and universal electronic stretching machine were used to characterize the foamed board, and the effect of modifier dosage on the dimensional stability of the foamed board was discussed. The results show that when the TA content is 3% of HCC, the glass transition temperature of PVC foam board is 88.1 ℃, the temperature of Vicat softening point is 75.21 ℃, and the PVC foam board has excellent dimensional stability, and the cell structure is stable and uniform, and has the best tensile strength of 6.17 MPa. Modified HCC particles have good dispersion, strong binding ability with PVC, and high dimensional stability of PVC foam board can replace the use of wood in home decoration boards, which is of great significance to protect the environment.

A lightweight and cooling woven fabric for summer was developed by selecting and combining different cooling fibers. Twelve samples were produced by selecting polyester/mint blended yarn as warp yarn, nylon fiber as weft yarn and plain, and twill and satin as fabric weave to investigate the impact of different weft yarns and fabric structures on the thermal and moisture comfort properties of the fabrics. The results showed that twill and satin fabrics had better thermal and moisture transfer performance; plain weave fabrics provided a good cooling sensation upon contact; cool nylon indeed enhanced the cooling of the fabric, but it showed poor moisture transfer performance in tightly woven structures. Micro-denier nylon had similar thermal and moisture transfer performance to cool-feel nylon but had lower air permeability and cross-sectional nylon had better moisture transfer performance but lower thermal conductivity.

The energy conversion efficiency of CH₃NH₃PbI₃ (MAPPbI₃) perovskite solar cells is closely related to the quality of the perovskite film. To obtain high quality perovskite films, the film preparation method and process were optimized. It was found that the green solvents, propylene glycol methyl ether acetate and glycerol, can promote nucleation of PbI₂ particles, provide heterogeneous nucleation sites for CH₃NH₃PbI₃ perovskite crystals, and thus facilitate the rapid growth of perovskite crystals. Compared to perovskite films treated with the common toxic solvent chlorobenzene, films treated with propylene glycol methyl ether acetate and glycerol have larger grain size, lower root-mean-square value, and greater surface roughness optimization. This can result in a uniform, full-coverage perovskite film that is close to the perovskite carrier diffusion length. The performance of devices under different treatment conditions was tested and it was found that compared to CH₃NH₃PbI₃ perovskite solar cells treated with chlorobenzene (energy conversion efficiency of 17.86%), the device treated with green solvent glycerol had the highest efficiency of 21.60%, which is an increase of nearly 21%. These experimental results have some reference value and guiding significance for researchers in this field to obtain environmentally friendly high-quality perovskite type solar cells in the future.

Inclusions have an impact on the fatigue strength and fatigue life of steel, but inclusions in large samples cannot be accurately imaged using X-ray micro computer tomo-graphy(X-ray micro-CT). This study provides a novel approach to obtain the three-dimensional morphology of inclusions in large steel samples. To realize the three-dimensional features of inclusions in large alloy samples, this study used a nonaqueous electrolysis method to obtain inclusions; then scanning electron microscopy was performed to observe and analyze the electrolyzed inclusions.Furthermore, the electrolyzed inclusions were aggregated into cylindrical samples and finally scanned with X-ray micro-CT to obtain their three-dimensional information, and the obtained dimensional data of the inclusions were statistically analyzed.

The Exfresh fiber is a new type of modified acrylic fiber with fine denier and antibacterial properties; it is fabricated by adding an antibacterial agent to the spinning stock solution. The surface morphologies, mechanical properties, moisture absorption properties, specific resistance, friction properties, and curling properties of the Exfresh and ordinary acrylic fibers were tested and compared in this study. The elemental composition and chemical bonds of the two fibers were analyzed via X-ray photoelectron spectroscopy (XPS). Furthermore, the moisture-absorbing quick-drying and moisture-absorbing heat-generating properties of the Exfresh blended fabrics were tested. Results showed that the Exfresh fiber featured a circular cross-section, rough longitudinal surface and dense grooves as well as a low linear density, excellent mechanical properties, and high spinnability. Additionally, it has a lower specific resistance and higher friction coefficient than the ordinary acrylic fiber, thereby making it difficult to produce static electricity. Results of the XPS analysis showed that the added antibacterial agent was a quaternary ammonium salt. Additionally, the evaporation rate of an Exfresh fiber-blended fabric is bigger than 0.18 g/h, and its maximum moisture-absorbing heat-generating temperature rise is bigger than 4 ℃. Moreover, it exhibits excellent moisture-absorbing quick-drying and moisture-absorbing heat-generating properties, and can be used to develop multifunctional fabrics.

EKS fiber is a subacrylate fiber with significant hygroscopic-heating properties. In this study, the surface morphologies of EKS and acrylic fibers were compared, and their mechanical properties, friction properties, specific resistance, curling properties, moisture absorption and liberation properties, and hygroscopic-heating properties were tested and analyzed. The results showed that compared with the acrylic fiber, the EKS fiber featured a circular cross section and rough longitudinal structure as well as low breaking strength, friction coefficient, specific resistance and curl rate; moreover, it featured a high linear density, elongation at break, and moisture recovery rate. With the initial absorption rate and liberation rate being 0.39% min^-1 and 8.94% min^-1, respectively, the moisture absorption and liberation rates of the EKS fiber decreased exponentially with time, and the time required to achieve the absorption and liberation balance was longer than that for the acrylic fiber. The EKS fiber exhibited good hygroscopic-heating properties with a maximum hygroscopic-heating value of 8.2 ℃, which was 4.7 ℃ higher than that for the acrylic fiber.