A research and test system for the carbon anode plate preparation technology was established to optimize the physical and chemical indicators of carbon anode plates, such as bulk density, resistivity, and compressive strength, and improve the operating cycle. In this study, a carbon plate was prepared via a combination of high-temperature molding and freeze drying using a formulation with asphalt content much lower than the industry standard. The experimental results show that the density of the carbon plate is increased by 0.02–0.04 g/cm³ by improving the drying method. The carbon plate prepared in the laboratory has a bulk density of 1.814 g/cm³, resistivity of 29.8 µΩ·m, and compressive strength of 89.27 MPa. The bulk density, room-temperature resistivity, compressive strength, graphitization, and other key indices of the carbon plates made in the laboratory and those procured from a factory in Shanxi, Datong, were tested. Additionally, the specimens were analyzed using thermogravimetry-differential scanning calorimetry, scanning electron microscopy, and X-ray fluorescence. The laboratory-made carbon plates were superior to the factory specimens in terms of all the indicators tested. The process in this study improves the performance of the carbon anode plate and is used to provide technical support for electrolytic fluorine production in enterprises. The carbon plates prepared in the laboratory fully meet the process requirements of a medium-temperature electrolytic fluorine production line, which indicates the possibility of its use in the stable production of fluorine gas.

Ni nanoparticles were coated uniformly on the surface of WC powder via a facile electroless plating method (abbreviated as WCN-EP), and then consolidated for mechanical and corrosion resistance performance characterization, in comparison with hand mixed WC-Ni (WCN-H). Under the optimized electroless plating parameters, Ni particles, less than 1 µm in average diameter, were found to be uniformly and densely wrapped on the surface of the tungsten carbide matrix of WCN-EP. In comparison, in WCN-H, the Ni particles about 1.8 µm in average diameter, were randomly distributed together with irregular WC particles. The uniform coating of Ni was found to assist the densification process of WCN-EP effectively, with higher densities and less pores than those of WCN-H at the Ni content of 10.6wt%, 25.5wt%, and 30.3 wt%. However, at the Ni content of 18.8wt%, the relative densities of WCN-EP and WCN-H both increased to the maximum value of 98%. The maximum hardness of the consolidated WCN-EP was 82.6 HRA, about 1.2 HRA higher than that of WCN-H. In addition, the consolidated WCN-EP also exhibits a superior corrosion resistance by the polarization curve analysis at an electrochemical workstation..

A new strategy to fabricate oxygen-promoted Cu,N co-doped carbon (OP-CuN@C) composites is reported. The strategy consists of only two simple steps: chemical polymerization and high temperature carbonization. Electrochemical measurements were conducted to investigate the catalytic activity and mechanism of ORR on the resulting samples. All the electrochemical results indicate that OP-CuN@C exhibits the best ORR catalytic activity. The ORR onset potential of OP-CuN@C is slightly lower than that of commercial Pt/C catalyst. The good performance is attributed to the large specific surface area, high content of heteroatoms (pyridinic, graphitic nitrogen, and oxygen atom) and synergistic effect between divalent copper and nitrogen dopant.

The electrical conductivity of graphene/cement composite before and after carbonation was tested by a four-electrode method. The General Effective Media equation was adopted to fit the experiment results. EIS (electrochemical impedance spectroscopy) was employed to study the effect of carbonation on conductivity of graphene/cement composite. The mechanism was analyzed by SEM (scanning electron microscopy). It is revealed that electrical conductivity increases with increasing carbonation depth when the graphene content is less than 2.0%. In this case, the electrical conductivity of composite depends on cement matrix which can be enhanced by carbonation product through filling pores. When the graphene content exceeds 3.3%, the electrical conductivity decreases with increasing carbonation depth. The conductive path is mainly formed by graphene chains which can be broke by carbonation product. The GEM (General Effective Media) equation fits the experimental results well and can be used to calculate the electrical conductivity of graphene/cement composite after carbonation.

Nano-pellet α-Al₂O₃ was prepared using aluminum nitrate as precursor and urea as fuel by a fast method of solution combustion synthesis. The formation of the nano material was dependent on the molar ratio of fuel/oxidant, calcination temperature, and foreign metallic ions. The prerequisite conditions of the formation were a suitable fuel/oxidant molar ratio larger than two and calcination temperature higher than 673 K. Foreign ions, Ce⁴⁺ or Co²⁺, hindered this formation via promoting the generation of stable penta-coordinated Al³⁺ ions due to strong interaction with alumina, were revealed by ²⁷Al NMR spectra. Such Al³⁺ ions were recognized as a critical intermediate state for the phase transformation of alumina and their presence deterred the transformation. The nano-pellet morphology of the product demonstrated a specific surface area of 69 m²/g, of which the external surface area occupied 59 m²/g. It was found that the supported cobalt acetate on such nanopellets existed as nanoparticles attached to the external surface, evidenced by the TEM characterization. The prepared catalyst could efficiently catalyze the selective oxidation of cyclohexane under the reaction condition of pressure under 0.8 MPa, temperature at 373 K, and time for 4 hours. The conversion of the reaction achieved up to 7.9%; while the cyclohexanone selectivity was 42.7% and the cyclohexanone and cyclohexanol selectivity was 91.6%. This catalytic performance recommends the supported cobalt acetate on the inert nano-pellet α-Al₂O₃ as a promising catalyst for the selective oxidation of cyclohexane.

Aluminum sol, dry gel, and film were prepared by sol-gel and a dipping-withdrawing method. The effect of polyethylene glycol (PEG) on the behavior of aluminum sol, gel, and film was investigated by DLS, rotary viscometer, XRD, IR, EPMA, and light microscope, respectively. The solid gels drying at room temperature was identified as amorphous phase, and the addition of PEG nearly has no effect on the structure of aluminum dry gel. It is indicated that the sol viscosity decreases with the PEG content increasing, while the micelle size in sol decreases first then increases. The uniformity and attached particles of the film are improved to a certain extent after PEG addition. According to the analytic results, we demonstrate that the improvement is caused by low viscosity and small micelle size of sol resulting from the PEG addition.

A polarizing microscope, X-ray diffraction (XRD), fourier transform infrared spectrometer (FTIR), scanning electron microscope and energy dispersive spectrometer (SEM-EDS), X-ray photoelectron spectroscopy (XPS), and micro computed tomography (Micro CT) were used to investigate the relation between the structure and properties of the composite. Meanwhile, the physical properties, mechanical properties and strength mechanism were researched. The experimental results show that the structure and morphology of coated phosphogypsum remain intact in the composite, which shows good compatibility and forms a clear interface layer of transition zone between the coated phosphogypsum and the matrix, conforming to the structure of particle reinforced inorganic composites. The emulsion coated phosphogypsum has a certain strengthening effect on the aluminous rock mineral polymer composite. The compressive strength of the composite can reach 16.5 MPa when the amount of coated phosphogypsum is 40%, and the apparent density is 1.75 g·cm⁻³, which is significantly lower than that of common concrete; the thermal stability of the composite is also improved to a certain extent. Some certain chemical reactions occur in the process of forming the matrix of aluminous rock mineral polymer materials, with a structure of three-dimensional network. The research will provide a new way for the comprehensive utilization of phosphogypsum and low-grade aluminous rock.

TiSi₂ reinforced boron phenolic composites (TP) and Vitreous silica fabric reinforced TiSi₂/boron phenolic composites (VTP) were prepared by compression molding, and their thermal, mechanical, ablation properties were studied. TG results show that thermal stabilities and residual carbon rate of boron phenolic are improved after introducing TiSi₂ particles. Compared with VTP-0 (containing 0 phr TiSi₂), flexural strength of VTP-60 (containing 60 phr TiSi₂) pyrolysis product increases by 29.5% at 1 200 °C. Raman spectrum shows that TiSi₂ particles promote the ordering of the glass carbon structure of VTP pyrolysis product. Compared to VTP-0, the linear and mass ablation rates of VTP-60 reduce by 32.1% and 77.5%, respectively. XRD and SEM indicate the formation of an oxide coating layer, TiO₂-SiO₂, integrates the bulk and protects the underlying materials from damage under high temperature oxygen-containing airstream. All these results prove that mechanical properties of pyrolysis product, thermal, and ablation resistance are improved by addition of TiSi₂ particles.

With the risk of disappearing for the rock paintings considering long-term exposure in Helan Mountain, the freeze-thaw(F-T) cycling experiments were carried out with 12-hour F-T cycling (0, 10, 20, 30, and 40 F-T cycles) under five kinds of confining pressures(5, 10, 20, 30, and 40 MPa). The acoustic emission (AE)detect technology was used to reveal the rock fracturing characteristics during the triaxial compression test whole process. The stress-strain relation changes along with different confining pressures and F-T cycles. Peak stress and residual stress changes along with different confining pressures and damages, and the variation of axial stress-AE ringing counts-time changes along with different confining pressures and F-T cycles. The damage variable with AE parameter under F-T and force coupling was defined for the first time, and the damages model was established. The experimental results show that the F-T cycles lead to the decrease of rock strength and the gradual transformation of compression failure mode from brittleness to plasticity. The confining pressure provides a certain ability to resist deformation and inhibit crack growth for rock samples after F-T cycles. The temporal and spatial evolution law of AE counts well corresponds to the loading and failure process of the rock samples. The AE 3D positioning technology can accurately capture the development position and direction of internal cracks and pores of rock, and the failure form is conical shear failure. The established damage model has a better fittingness between the theoretical calculation results and the test results, and is reasonable to be used in the future for protection of Helan Mountain rock painting.

To reveal and utilize the interaction between Tamm plasmon polaritons (TPPs) and two-dimensional materials are promising for exploiting next-generation optoelectronic devices. Herein, the coupling mechanism between metal TPPs and monolayer WS₂ along with its differences from that between metal TPPs and graphene was studied in detail by using the transfer matrix method. The experimental results show that it is difficult to excite TPPs at the boundary between monolayer WS₂ and dielectric Bragg reflector (DBR) such that the strong coupling mainly stems from the interaction between metal TPPs and exciton in monolayer WS₂. However, the coupling in graphene/DBR/metal hybrid structure derives from the interaction between two different TPP resonance modes. Thus, evolutions of Rabi splitting with various structural parameters including spacer thickness, incident angle and DBR period greatly differ from those observed in graphene/DBR/metal hybrid structure. In addition, the discrepancies induced via metal Ag and Au films as well as the possible influence mechanism were also discussed.

To investigate the variation in the degree of polymerization calcium aluminium silicate hydrate (C-A-S-H) gel and its role in the evolution of the strength of waterglass slag binders, the compressive strength, hydration products, degree of hydration of the slag, and the degree of polymerization of C-A-S-H gels of binders were examined. The experimental results indicate that the pH of the pore solution increased with an increase in the Na₂O concentration. However, mortar with an optimum compressive strength value of 81.0 MPa at 28 d was obtained when water glass modulus was 1.5. The main hydration product is a C-A-S-H gel for which the quantity and the degree of polymerization depend strongly on the Na₂O concentration; for a given range, both increase with increasing Na₂O concentration, thus yielding an enhanced strength. A further increase in the Na₂O concentration continuously increases the quantity of C-A-S-H gels while drastically reducing the degree of polymerization. The positive effect of the former is counteracted by the adverse effect of the latter, ultimately, leading to a decreased strength. Furthermore, we reveal that the degree of polymerization for C-A-S-H gels may be affected by pH, through a series of complex chemical reactions.

Taking a Cu55Ni45 alloy as experimental alloy systems, we systematically studied the method of obtaining deep undercooling of alloy melt. Stable deep undercooling of alloy melt was obtained by the combination of molten glass purification and cyclic overheating. Combined with the nucleation and growth mechanism of undercooled melt, the microstructure evolution and grain refinement mechanism of the alloy were systematically studied in a wide undercooling range. The grain refinement solidification structure under large undercooling was analyzed by EBSD technology. Combined with the typical characteristics of recrystallization in metallographic pictures, it was finally confirmed that the grain refinement was caused by recrystallization.

Both experimental and numerical approaches were used to study dynamic failure properties and patterns of flattened Brazilian discs, containing two prefabricated cracks intersected at a varying angle. Mechanism of crack initiation, propagation, and cut-through were scrutinized and influences of the intersection angle on specimen strength and acoustic emission performance were also studied. All primary cracks initialize near the middle or the tip points of the upper prefabricated crack, and they continue to develop along the load direction and finally cut through the specimen. The secondary cracks could be observed in directions almost horizontal or parallel to the directions of prefabricated cracks. Furthermore, it is found that stress intensity factor reaches its maximum for specimen with intersection angle of 0 degree.

Hollow silica nanospheres with radical pore on the surfaces were prepared using the assemblies of valine amphiphilic small molecule and benzene as double-templates through sol-gel method in tetramethylammonium hydroxide (25wt%) solution at the stirring rate of 1 000 rpm. There are a lot of vertical pores on the surfaces of the hollow spheres after removing the templates in Muffle furnace at 550 °C for 5 h. The sample was characterized using field-emission scanning electron microscopy, transmission electron microscopy, Brunauer-Emmett-Teller (BET), X-ray diffraction, etc. The diameter, the vertical pore size of the nanospheres and the BET surface areas are 30–100 nm, 4.2 nm, and 570.5 m²/g, respectively. Because the high porosity and specific surface area, this kind of hollow sphere is the excellent antimicrobial carrier. The antibacterial activities of the silica nanospheres were evaluated by using a bacterial growth inhibitory assay. The experimental results show that the silica hollow spheres loaded with Ag⁺ have a good bactericidal effect.

The active oxygen species in the catalytic oxidation system of Fe(III)PcTs-t-BuOOH were identified, and the mechanism of the catalytic oxidation of phenolic substrates was proposed. Quinone imine molecules, the main products of catalytic oxidation reaction, can be adsorbed on the surface of CdTe QDs, resulting in their fluorescence quenching. A dual function of catalytic oxidation and fluorescence sensing was developed for the determination of dichlorophenol (DCP) based on the Fe(III)PcTs-BuOOH-CdTe QDs system. The linear detection range of DCP was 1×10⁻⁶–1.3×10⁻⁴ mol/L, and the detection limit 2.4×10⁻⁷ mol/L. This method was characterized by high selectivity, good repeatability and desirable stability, presenting promising potentials for analyzing DCP concentration in real water samples.

Rolling process based on the plastic deformation as a surface strengthening treatment was employed, aiming to improve the wear resistance ability and functional performance of the high carbon equivalent gray cast iron (HCEGCI). The microstructures and tribological performance of the untreated and rolled samples were characterized. In addition, the wear mechanism of HCEGCI samples was also studied via pin-on-disc tests. The experimental results show that the as-rolled samples possess the structure-refined layer of 15 µm and work-hardened layer of 0.13 mm. In comparison with the surface hardness of untreated samples, the surface hardness of as-rolled samples increases by 84.6% (from 240HV0.1 to 443HV0.1) and the residual compressive stresses existed within the range of 0.2 mm. The wear rates of as-rolled samples were decreased by 38.4%, 37.5%, and 44.4% under different loads of 5 N, 10 N, and 15 N, respectively. The wear characteristics of the untreated samples mainly exhibit the peeling wear coupled with partial adhesive and abrasive wear. However, as for the as-rolled samples, the adhesive wear was limited by the structure-refined layer and the micro-crack propagation was controlled by the work-hardened layer. Therefore, the wear resistance of as-rolled samples can be improved significantly due to the low wearing degree of the friction contact zone.

The feasibility of applying the grain boundary character distribution (GBCD) optimization to Inconel 625 for improving the intergranular corrosion (IGC) resistance was studied. The GBCD was obtained and characterized by electron backscatter diffraction (EBSD) analysis, and its optimization was mainly attributed to annealing twins (Σ3) and twins related to boundaries formed during thermal-mechanical processing (TMP). Through TMP of 5% cold rolling and subsequent annealing at 1150 °C for 5 min, the proportion of low Σ coincidence site lattice (CSL) grain boundaries of the Inconel 625 can be enhanced to about 35.8% which mainly were of Σ3 ⁿ (n=1, 2, 3) type. There is an increase of 24.8% compared with the solution-treated sample, and simultaneously the large-size highly-twinned grain-cluster microstructure is formed. The grain-cluster is mainly composed of Σ3-Σ3-Σ9 or Σ3-Σ9-Σ27 triple junctions, which is mainly caused by boundary reactions during grain growth. Among them, the IGC resistance of Σ3 grain boundaries, Σ9 grain boundaries and random grain boundaries is sequentially weakened. With the increase of the low ΣCSL grain boundary fraction, the IGC resistance of Inconel 625 improves. The essential reason is the amount of Σ3 boundaries interrupting the random boundary network increases and the large grain-cluster arrests the penetration of IGC.

The solidification microstructures of undercooled Ni90Cu10 alloys under different undercoolings were studied systematically by means of melt coating and cyclic superheating. In the obtained undercooling range, the solidification structures of the two undercooled alloys have similar transformation processes, and there are two kinds of grain refinement structures under the conditions of low undercooling and high undercooling, respectively. The microstructures of the two grain refinement processes were analyzed in more detail by electronic backscattering diffraction technique. Under the condition of small undercooling, dendrite remelting is considered to be the main reason of grain refinement. However, under the condition of high undercooling, the existence of annealing twins and obvious migration of grain boundary are important evidences for the occurrence of recrystallization process.

The effects of various general and heavy metal ions in acidic cadmium-containing wastewater on SBR desulfurization and cadmium removal under different concentrations were studied. CrO₄ ²⁻ and S²⁻ inhibited SRB mineralization, and Mg²⁺, Ca²⁺, Fe²⁺, and Fe³⁺ promoted SRB mineralization at low concentration (<50 mg/L). The inhibitory concentrations of Cu²⁺, Mn²⁺, Co²⁺, Zn²⁺, Pb²⁺, Hg²⁺, Cr³⁺, and Ni²⁺ were 10, 30, 2, 20, 25, 5, 30 mg/L, respectively. The inhibition order was Co²⁺>Hg²⁺>Cu²⁺>Ni²⁺>Zn²⁺>Pb²⁺>Mn²⁺>Cr³⁺. Furthermore, the inverted microscopy and scanning electron microscopy (SEM) were used to observe the sediment crystallization process from macroscopic and microscopic viewpoints in the optimized ion environment. The experimental results show that under the mineralization of SRB, cadmium sediment crystallization is mainly divided into the rapid growth of bacteria, crystal nucleus production, block formation, and crystallization occuration. At the same time, X-ray diffraction (XRD) and energy-dispersive spectra (EDS) have also confirmed the sediment and crystallization.

To synthesize three different grafting ratios of gallic acid (GA)-chitosan (CS) copolymer by a free radical mediated grafting method, which is further applied to the field of antibacterial materials, crosslinking structures of the compound GA-CS copolymer were characterized, fully indicating that gallic acid is resoundingly grafted onto chitosan. The grafting ratios of three copolymers GA-CS are 45.71% (I), 36.12% (II), and 18.96% (III) were determined by UV-Vis spectrophotometer. The minimum inhibitory concentrations of three GA-CS copolymers are 30 µg/mL against Escherichia coli and are ranged from 250 to 550 µg/mL against Staphylococcus aureus. By counting viable bacterial colonies, it can be found that antibacterial property is preferable by increasing the grafting ratio of GA-CS copolymers. Findings of investigation on aforementioned bacteria experiment indicate that the CFU/mL values of GA-CS (I, II, III) are 2.04×10⁶, 7.56×10⁶, 1.48×10⁷ to Staphylococcus aureus, and 2.96×10⁶, 1.01×10⁷, 2.14×10⁷ to Escherichia coli after 12 h treatment. In addition, the interaction process between GA-CS copolymer and bacteria can be observed through a transmission electron microscope. The specific manifestation is that the bacterial cell membranes are ruptured after being treated with the copolymer, which causes the cell contents to flow out, and the cell morphology is shrunk and out of shape.

A compound, 3-ethyl-3-hydroxymethyloxetane (EHO), was synthesized with diethyl carbonate and trihydroxypropane as raw materials, 3-ethyl-3-allylmethoxy oxetane (EAMO) was synthesized with EHO and allyl bromide, and 1,1,3,3,5,5-hexamethyl-1,5-bis[(3-ethyl-3-methoxyoxetane)propyl]trisiloxane (HMBEMOPTS) was synthesized with EAMO and 1,1,3,3,5,5-hexamethyltrisiloxane (HMTS). HMBEMOPTS is a novel UV-curable oligomer. The test of photo-DSC shows the photosensitivity of HMBEMOPTS is better than the ordinary oxetane, 3-ethyl-3-[(3-ethyloxetan-3-yl)methoxymethyl]oxetane. HMBEMOPTS was mixed with bisphenol A type epoxy resin E-51 to prepare a cationic UV-curable system, and triarylsulfonium hexafluoroantimonate (UV-6976) was used as a cationic photoinitiator. The mechanical tests of coating films prove that when the mass fraction of HMBEMOPTS is 50%, the mechanical properties of the curing system are the best. The impact strength of the UV-curable films is measured to be 40 kg-cm and the flexibility is 2 mm; the tensile strength and flexural strength of the prepared specimens are 20.74 MPa and 13.43 MPa, respectively. The experimental results show that HMBEMOPTS can effectively improve photosensitivity and flexibility of the photosensitive resin.