Mercury-free zinc-alloy powder were electrodeposited from alkaline solution. Additives containing lead, indium or bismuth were added in the electrolyte and zinc powders with corresponding compositions were obtained. The relations between adding amounts of additives and the contents of corresponding compositions in zinc powder are not linear. Aluminum and calcium cannot be co-deposited with zinc. Electrodeposition effectively reduced the contents of harmful impurities. Gas evolution of electrodeposited Zn-Pb-In-Bi alloy powder was less than that of atomized mercury-free alloy powder.

The nano-sized metal-oxide ultrafine powders of the low-melting-point metals can be prepared rapidly using a new atomizing - combustion technique by which the superheated metal melt was atomized with a ceramic atomizing-burner first through the medium of high pressure oxygen, then the metal fog burned up in a combustion chamber. Based on the experiments, nano-sized SnO₂, In₂O₃ and Bi₂O₃ powders were obtained successfully by atomizing-combustion technique. The mechanism and process parameters of the technique were discussed. The phase structure and the microstructure of these metal-oxide ultrafine powders were studied by XRD and TEM respectively. The biggest size of grain was less than 50 nm, and 1 kg metal-oxide ultrafine powder can be prepared in only 45–48 seconds.

Electron probe microanalysis and SEM were employed to study the phase equilibria and diffusion paths in C-Ni₈Ta, C-Ni₃Ta, C-Ni₂Ta diffusion couples after annealed at 1100 °C for 120 h or at 1200 °C for 120 h and then at 1100 °C for 24 h. Attempt was made to use the calculated stability diagram of carbon activity to explain the experimental observations. The phases formed in the diffusion layers were all in the prediced ranges.

The effect of initial microstructures on the heat treatment behavior of can-forged titanium aluminide alloy has been studied. Optical microscopy and EDX analyses results show that different initial microstructures, including difference in dislocation density, phase distribution and morphology, have inherent effects on the final heat treatment microstructure although at the same heat treatment temperature. An almost full lamellar (NFL) microstructure with an average α₂/γ colony size of 20 µm was obtained through adjusting initial microstructure.

The problem was found that the nucleation and growth of diamond are different on each side of flaky catalyst in the cubic high pressure diamond synthesis system. Some theories explainning this difference were introduced in the paper. The synthesis cavity and the forces on flaky ctalyst were analysed. The results show that the stress makes the transmission velocity of carbon different on each side of catalyst slice, which causes the difference of nucleation density of diamond between two sides of the slice.

A new densification method of chemical manganese dioxide (CMD)-NaMnO₄ densification has been developed. This MnO₂ produced by NaMnO₄ oxidation possessed γ-type structure. After the crude MnO₂ was densified, the tap density of the MnO₂ powder could be increased from 1.2 to 2.0 g/cm³. The discharge capacity is higher than that densified by other oxidizers.

Caustic soda leaching liquor of tungsten ore always contains a certain amount of free alkali. General method of removing free alkali in the liquor is to neutralize it by inorganic acid. A new method, i.e. applying electrolysis with ion-exchange membrane to recover free alkali from caustic soda leaching liquor of tungsten ore, was proposed in the paper. In the electrolysis cell the effective area of membrane is 100 mm×100 mm, the anode is β-PbO₂ plated at screen of titanium net, the cathode is active nickel plated at screen of stainless steel net, and the membrane is a kind of perfluorsulphonic acid membrane. Some effect factors of electrolysis process including the NaOH concentration in anolyte and catholyte, distance between electrodes, temperature, current density, are investigated. The results show that, by choosing proper operating condition, the specific energy consumption can be controlled within 2 kWh · kg⁻¹ NaOH. Electrolysis with ion-exchange membrane can not only recover free alkali from caustic soda leaching liquor, reduce the consumption of inorganic acid, but also utilize the hydrogen gas produced in the process to produce tungsten powder.

The mechanism of beneficiation with air-dense fluidized bed has been theoretically studied in the paper. Focusing attention on the misplacing resources in separation process, the misplacing effects are divided into two parts called respectively as misplacing effect of viscosity and misplacing effect of motion. The proposed separation theory can reasonably explain the results of separation in different fluidization states. Experimental results in pilot and commercial plants showed that the air-dense medium fluidized bed is a high efficiency dry cleaning technique. The dynamic stability of fluidized bed density is directly affected by the variation of fine coal content in fluidized bed and can be controlled in expected range through measurement of fluidized bed density and adjusting of splitflow rate. With air-dense medium fluidized bed, various coals of size 50–6 mm can be efficiently beneficiated. The separation density can be adjusted between 1.2–2.2 g/cm³, and the probable error E_p value is about 0.06.

The fluidizing performance and density uniform stability of vibration fluidized beds were analyzed. The experimental results in 2000 mm×80 mm×200 mm model apparatus show that the vibration fluidized bed can efficiently separate fine coal of size 6–0.5 mm, the beneficiation lower limit is 0.5 mm, the E_p value is 0.07. A double-density fluidized bed was formed by which the bed structure was specially designed with a pyramidal part. It can efficiently turn out three products according to densities in a fluidized cascade. The suitable range of gas flow rate is 4.4–4.6 m³/h. In the lighter area, the separation density is around 1.49 g/cm³, and E_p value is 0.06. In the denser area, the separation density is about 1.85 g/cm³, and E_p value is 0.07.

The interaction between a flotation reagent and mineral surface not only depends on the bonding atom, but also depends on the adjacent atom of mineral surface, a flotation reagent and the medium in the system of flotation. Energy equation of a reagent interacting with mineral surface has been deduced from this model. Results of the studies indicate that the interaction energy between mineral surface and a reagent is about several dozen kJ/mol, and the relationship between adsorbing concentration of xanthate on mineral surface and interaction energy is the exponent form.

An acidic solution containing 280 mg/l silver and others was treated. In order to selectively recover silver without losing other metallic elements from the solution, cementation was adopted with metallic copper. The kinetics of cementation reaction and copper dissolution and mechanism of copper consumption were studied. The results indicated that the rate of cementation reaction and copper consumption were markedly increased with the increase of temperature. For the same cementation recovery of silver, copper consumption at elevated temperature was much higher than that at ambient temperature. Cementation rate and copper consumption rate also increased with the increase of stirring velocity, while copper consumption at different stirring velocity for the same recovery of silver was almost not different. Studies on the chemical mechanism of copper consumption showed that Fe³⁺ and residual leaching additive RH in the solution were the main factors that caused extra copper consumption in acidic solutions.

A modified hot wire method was applied to measure the thermal conductivity of different kinds of particulate materials. With a cylindrical device, a heating rod and two thermocouples, the measurement can be finished within several minutes. Compared with the reference data, the results obtained from the measurements were quite reasonable.

A new criterion of static-dynamic state mixed mode brittle fracture initiation in rock is suggested, i. e. the distortion strain energy criterion. When t→∞, the static-state distortion strain energy criteria and the formula for determiming static-state fracture angle are obtained. The new static-state criterion, suggested by authors, is in good agreement with the author’s experimental results. In addition, the relative accuracy of three current fracture theories and the new criterion in predicting static-state mixed-mode initiation fracture loading and fracture angle in rock have been evaluated experimentally.

A new photoelastic method of obtaining mode I stress intensity factor (SIF) is presented. The method considers the influence of far field stress, σ_ox, on the value of SIF. The only information needed for K_I calculation is the area between isochromatic fringe loops. The method is examined by two kinds of specimen in different load cases. Experimental results show that it is quite simple and of high precision.

The blasting experiment of the cement mortar model reveals that joint inclination affects blasted rock size distribution, which is an important index to evaluate the blasting effect. According to the fractal theory, the relationship is built up between fractal dimension and mass fraction of blasted fragments screened, that is, y_x=100 (x/x_m)^3−D. On the basis of the experiment results, the fractal dimension describing fragment-size distribution is calculated.

The age of alkali-rich porphyries in the western margin of Yangtze Platform is 30–50 Ma; the minerals mainly are orthoclase, quartz, plagioclase; the chemical composition is alkali-rich [(K₂O+Na₂O)>8%], highpotash[(K₂O+Na₂O)=5.09%−8.30%]; the content of ΣREE is relatively low, LREE is concentrated, without anomaly of europium; the average initial ratio of ⁸⁷Sr/⁸⁶Sr is 0.7073; the value of δ³⁴S similar to that of the meteoritic sulfur; the ratio of Pb isotope corresponds to that of upper mantle; metallogenic types belong to Cu, Mo, Au, Ag, Pb, Zn polymetal mineralization and rare, rare-earth metal mineralization.

An H_∞ controller for an active suspension system is designed, which has taken the performance of ride comfort and the system robustness into account. Simulation results show that a concentrated weighting of the car body acceleration output, for the frequency where human being are most sensitive to vibration, has been executed by introducing the frequency dependent weighing function, thus the suspension acceleration frequency response characteristic can be improved. It is also pointed out that the designed controller is effective in the system robustness against the fluctuation of parameter of system.

Nine 5-(β-substituted stylryl) salicyladehyde derivatives were prepared by PTC Witting reactions in the paper. The stereochemistry of the Witting reactions and the substituted effect on the UV spectra of salicyladehyde derivaties have been reported. It was observed that the spectra undergo a red shift as the conjugative effect of substituted becomes stronger. A good linear relationship between the shift of UV of p-substituted compounds and conjugation effect was obtained. It showed that the Hammett equation may be applied to the UV frequencies of the title compounds.

The method of determining the structures and parameters of radial basis function neural networks (RBFNNs) using improved genetic algorithms is proposed. Akaike’s information criterion (AIC) with generalization error term is used as the best criterion of optimizing the structures and parameters of networks. It is shown from the simulation results that the method not only improves the approximation and generalization capability of RBFNNs, but also obtain the optimal or suboptimal structures of networks.