Effects of electrochemical deposition time on the phase, morphology, bioactivity of hydroxyapatite (HA) coating and the bonding strength with the substrate were investigated adopting alkali-treatment of titanium alloy followed by electrochemical deposition. Results show that the electrochemically deposited coatings prepared on the surface of alkali-treated titanium alloy are composed of flake HA phases, and the electrochemical deposition time has no effect on the phase composition of the coatings, but will bring impact to the coating thickness. After 60 min deposition, the obtained HA coatings is very compacted and has the bonding strength with the substrate up to 17.85 MPa. It is shown that the HA coatings obtained after each deposition time have good bioactivity. In the simulated body fluids (SBF), CO₃^2- substitutes PO₄^3- in the HA into apatite to form steamed bun-shaped carbonated hydroxyapatite（CHA），with the diameter of 7-8 μm. After being immersed in SBF for 3 days，the CHA can be spread all over the surface of HA.

The effects of brightening agent, such as polysodium dithiodipropanesulfonate (SPS) and sodium 3-mercapto-1-propanesulfonate (MPS), on electrodeposition of Cu from electrolyte with Cu²⁺, H₂SO₄, Cl^- concentration of 85 g/L, 100 g/L and 20 mg/L respectively were studied by adopting linear scanning voltammetry and cyclic voltammetric stripping (CVS), and the effects of SPS and MPS on the tensile strength, elongation, glossiness and roughness of electrolytic copper foil for Li-ion batteries were discussed. The results show that SPS and MPS can promote copper electrodeposition, and also SPS is better than MPS in promotion. However, the compounding with collagen and hydroxyethylcellulose will result in less promotion of copper electrodeposition. In addition, SPS is conducive to improving the tensile strength of copper foil, and MPS is conducive to improving the elongation of copper foil. With concentration of SPS and MPS at 1 mg/L and 1.5 mg/L respectively, the prepared copper foil has flat and dense surface, with better glossiness and roughness.

In order to recover and utilize high value-added iron phosphate waste, an experimental study was carried out by adopting a process consisting of hydrochloric acid leaching, replacement of iron powder for copper removal, and hydrolyzation and chemical precipitation for removal of titanium and aluminum therein. The results show that after 1 h leaching at 60 ℃ with hydrochloric acid concentration of 25%, liquid-solid ratio of 6 mL/g, the leaching rate of iron can be up to 98.7%. And then after 35 min reaction at 60 ℃ with the initial pH of the solution controlled at 0.6, the addition of iron powder at an amount of 0.55 times of the molar number of iron in the leaching solution, the removal rate of copper and titanium can reach 96.2% and 83.6% respectively. By the following process of hydrolyzation and chemical precipitation with sodium fluoride 8 times of the molar number of aluminum, the removal rate of titanium and aluminum can reach 97.6% and 99.3% after 30 min reaction at 40 ℃ with pH of 1.9. It is shown that the content of impurities in the leaching solution meets the requirements for the subsequent synthesis of iron phosphate for batteries.

To utilize efficiently valuable metal resources containing lithium and beryllium, flotation experiments were conducted based on the study of ore properties. A lithium-beryllium bulk flotation process was used and the influences of dosages of regulator, activator and collector, and the stirring time of regulator on the flotation performance of lithium polymetallic ore were investigated. Based on the determined optimal dosages of calcium chloride and collectors of GYLZ and GYM3, a closed-circuit test produced a lithium concentrate with Li₂O grade and recovery of 6.10% and 94.01% respective, and BeO grade and recovery of 0.12% and 88.53%, respectively, achieving efficient recovery and utilization of lithium and beryllium resources in lithium polymetallic ores.

A kind of contaminated paddy soil was taken for pot experiment by adding FeSO₄ to investigate the impact of FeSO₄ on the formation of iron plaques on the root surface and the migration of the Cd from Cd-contaminated paddy soil. Results show that with the addition of FeSO₄ increased from 0 to 320 mg/kg, the pH value of the paddy soil tends to decline, maximally by 0.70. The TCLP-Cd content in the potting soil rises to a certain extent compared to the control group. The addition of FeSO₄ significantly reduces the Cd content in leaves, husks, and brown rice, as well as effectively increases the amount of root iron plaque, thus the absorption of Cd in the soil by rice is moderately controlled. However, the addition of external iron resource can bring impact to the pH of soil and bioavailability of Cd, so it is recommended that in practical operation, FeSO₄ should be added with some alkaline restorative materials such as lime to contaminated paddy fields for enhancing the control.

Beneficiation tests were conducted to process the low-grade cobalt-nickel ore from Hebei Province by adopting an asynchronous flotation flowsheet consisting sequentially of staged grinding, flotation of sulfide minerals and flotation of sulfurized oxide minerals. In the study, combined depressants were used for better depressing of slime, while regrinding process was introduced to intensify the sulfurization effect. Finally, a cobalt-nickel sulfide concentrate with Co grade of 2.00% and Ni grade of 3.90% and a cobalt-nickel oxide concentrate with Co grade of 1.47% and Ni grade of 2.73% were obtained. The total Co recovery and total Ni recovery reached 77.61% and 79.20%, respectively. In this way, the preliminary enrichment and recovery of Co and Ni resources can be realized, laying a foundation for their further purification.

The occurrence state of iron minerals in a kind of kaolin ore in Guangdong is relatively complex. A portion of iron minerals is irremovable as they disseminate in the lattice of kaolinite, illite and other minerals in an isomorphic manner. For this reason, the calcined kaolin concentrate possesses a lower whiteness than the natural whiteness. In order to efficiently exploit and utilize the kaolin ore, a process consisting of slurry tamping, spiral classifier classification and hydrocyclone classification was adopted, resulting in a kaolin concentrate grading 30.02% Al₂O₃ at 61.70% recovery with the content of impurity Fe₂O₃ at 1.15%, which can reach grade III standard of kaolin for ceramic industry. The classification downflow was then subjected to a process consisting of grinding, magnetic separation and hydrocyclone classification, resulting in a quartz sand concentrate and a sericite concentrate. The quartz sand concentrate, containing 97.11% SiO₂ and 0.058% Fe₂O₃, can satisfy the standard for low quality quartz for glass industry, and the sericite concentrate, containing 7.07% K₂O, 31.22% Al₂O₃ and 48.32% SiO₂, with natural whiteness at 65.53%, can be used in the coating industry. The magnetic separation results in the tailings with a yield of 8.41% and SiO₂ content of 76.33%, which can be used as auxiliary materials for building sand. Through this process, different minerals can be effectively separated to achieve the purpose of comprehensive utilization of kaolin ore.

A vertical stirring mill was introduced for regrinding the graphite concentrate from the rougher in a graphite mine of Heilongjiang Province. Using ceramic ball as the grinding medium, the influences of processing parameters, including rotation speed of mill, diameter of medium ball and grinding time, on the grinding and flotation performances of graphite ore were investigated. The graphite ore was beneficiated adopting an open-circuit flotation process after it was milled with the optimized grinding parameters including alternating (slow-fast-slow) rotation speed, medium ball diameter of 8-10 mm and grinding time of 5 min. The as-obtained graphite concentrate, with the 24.51% in a size fraction of -0.045 mm, has a fixed carbon content of 95.83% and large-flake graphite content of 14.27%.

A numerical model was established by using LS-DYNA software and then used to simulate the influence of pre-split fracture with width of 3 cm and 5 cm, respectively, on blasting effect. It is found that wider pre-split fracture can bring a better effect of blasting vibration attenuation, with the maximum amplitude decay rate of 46%. Based on pre-split blasting tests with different borehole sizes, the on-site vibration monitoring results have verified the correctness of the rule. It is concluded that the parameters of pre-split blasting should be selected based on the actual working conditions in consideration of protection of surrounding buildings.

A Gamma-ray concentration meter based on Kalman filtering was designed, and the relationship between ray intensity attenuation and slurry concentration was established by analyzing the measurement principle of ray concentration meter. To suppress the disturbance of the results, an optimal estimation of ray intensity was actualized by using Kalman filtering. The corresponding concentration is segmentally simulated and calculated by using the least square method. The results show that the concentration meter can provide timely and accurate measurement, with a maximum error of 0.328 percentage points and a root mean square error of 0.194 percentage points, presenting effective improvement in accuracy.