The effect of electron beam irradiation on magnetic property of iron bearing minerals was investigated by susceptibility measurements. The results show that the magnetic susceptibility of iron bearing sulfide minerals can be enhanced remarkably by strong beam current irradiation, while the magnetic susceptibility of oxidized iron minerals keeps unchanged and even is slightly reduced. The magnetic susceptibility of arsenopyrite can reach the ferromagnetic level. The particle size of irradiated minerals makes notable effects on magnetic susceptibility. The magnetic susceptibility of irradiated minerals is enhanced greatly with reduction of particle size, and the irradiation dose corresponding to the maximum magnetic susceptibility is decreased simultaneously. Exposure of pyrite to small beam current electron irradiation can only enhance its magnetic susceptibility from 4 to 5-fold. Enhancement of magnetic property by radiation induced defects and excitation in minerals is limited. Strong beam current electron irradiation provides a novel approach to enlarge the magnetic property differences between iron bearing minerals.

The changes of magnetic property of several iron bearing sulfide minerals after strong beam current electron irradiation are examined. Data shows that the magnetic susceptibility of arsenopyrite and chalcopyrite increases markedly compared to that of pyrite and marmatite. The magnetic susceptibility of arsenopyrite exceeds the lowest ferromagnetic limit 3000 cm3/g, while the susceptibility changes of other minerals are relatively slow. The irradiation dose is the dominate parameter determining the magnetic susceptibility change. Electron beam irradiation might be a potential method to enlarge the magnetic property distinction between the minerals for their magnetic separation.

In order to research the application of double microemulsion method for preparing nano-sized catalysts,Fe3+ doped TiO2 nano-particles were obtained in microemulsion of CTAB-butanol-cyclohexane-H2O with TiCl4 and NH3·H2O as raw meterials.The crystal structure of Fe3+ doped TiO2 nano-particles was characterized by XRD and the degradation of p-cresol was investigated for the photocatalytic activity of them.The results show that the photocatalytic activity increases with the increasing doping content of Fe3+ in a certain range and decreases with further increasing of doping content.The doped Fe3+ ions lead to decrease the particle size of TiO2 nano-particles.The small radius of Fe3+ and low melting point of Fe2O3 can promote the phase transitions of anatase to rutile.When the doping molar fraction of Fe3+ is 0.06%,Fe3+ doped TiO2 nano-particles calcined at 550 ℃ show the highest photocatalytic activity and emerge the mixed crystal of anatase and rutile.

Surface modification of wollastonite particles using titanate as a modification agent incorporated by simultaneous wet ultra-fine grinding in a laboratory stirred mill was investigated. The physical, physic-chemical and application properties of the modified wollastonite were measured and evaluated. The results showed that grinding intensity markedly influences the modification effect because of the mechano chemical effect. The hydrophilic surface of wollastonite was turned into a hydrophobic one after modification. The interaction between titanate and wollastonite under wet grinding circumstances was studied. It was suggested that physical adsorption and chemical adsorption of titanate coexisted on the wollastonite surface. The mechanical properties of polyethylene (PE) filled with the modified wollastonite powder were markedly improved.

The structures and compositions of pyrite surface before and after high energy electron beam irradiation were investigated by applying X ray photoelectron spectroscope(XPS)and X ray diffraction(XRD).The results show that irradiation does not change the shape and size of crystal cells of pyrite but may regulate the relative coordinate position of atoms in crystal cells.Irradiation in atmosphere can decrease the sulfur/ferrum atom ratio on pyrite surface and that in liquid may,on the contrary,increase the ratio.The reaction mechanism of pyrite surface under the irradiation of electron beam is analyzed.

Heavy metal pollution is a major concern in environmental treatment. In this paper, immobilization mechanisms of Cu2+ in an acidic solution by brucite were investigated. The final pHs of brucite suspensions with initial pHs of 2.0 and 1.6 rose to 6.8 and 6.03, respectively, after an agitation of 48 hours, which indicates that brucite has a good neutralization capacity for acidic media. When ionic strength of the suspension rose from 0.05 mol/L to 0.8mol/L, final pH and Cu2+ adsorption on brucite increased from 5.82 and 21.45% to 6.17 and 27.78%, respectively, which suggests that Cu2+ shows chemisorption reaction on brucite. The immobilization of Cu2+ in a brucite suspension is attributed to the synergism of neutralization and the adsorption capacities of brucite. Brucite samples adsorbing Cu2+ at a final pH of 5.8 were characterized by X-ray photoelectron spectroscopy (XPS), which indicates that there are two copper species on brucite surface. One species bonds with oxygen to form a structure of bulk brucite-O-Cu-OH, and another species is CuCO3 precipitate as a result of Cu2+ carbonation.

Surface modification of calcium carbonate particles using sodium stearate(SDS) as a modification agent incorporated with the simultaneous wet ultra-fine grinding in the laboratory stirred mill was investigated. The physical properties and application properties of modified calcium carbonate were measured and evaluated. The action mechanism between SDS and calcium carbonate in the modification was studied by infrared spectrometry(IR) and X-ray photoelectron energy spectroscopy(XPS). The results indicate that the crushing mechanic force intensity can obviously influence the modification effect of calcium carbonate because of mechano-chemical effect. The hydrophilic surface of calcium carbonate is turned into hydrophobic after modification. The properties of polyethylene(PE) filled by modified calcium carbonate powder is markedly improved. And the adsorption of SDS could occur by chemical reaction with calcium carbonate surface.

For obtaining precise powder classification to adapt the strict need for special size powder, a new method and apparatus which charges the particles with electrostatic charges and then put them into an electric field to make them classified in the particle sizes was presented in this work. The charging and classifying test was done on –75 μm copper powder and different sizes of SiC powder. The results show that the maximum ratio of charge to mass is 14.8 nC/g for copper powder, 90.6, 43.2, 50.7 nC/g for W10, W20 and W40 SiC powder samples respectively. The micrographs of the classified copper powder show that the high charge voltage leads to better classification result. The classification results of SiC powder are evaluated by cumulating mass fraction. The cumulating mass fraction of powder above 25 μm promoted from 3.77% to 2.39% for sample II and from 1.80% to 0.93% for sample III. The electrostatic classification of powder is a future potential method.

The ultra-large surface-to-mass ratio of two-dimensional (2D) materials has made them an ideal choice for electrodes of compact lithium (Li)-ion batteries and supercapacitors; however, only a small fraction of the massive 2D material space has been investigated for such applications. Here, combining explicit-ion and implicit-solvent formalisms, we develop an automated, first-principles-based, high-throughput computational framework to assess thousands of such materials. We define four descriptors to map “computationally soft” single-Li-ion adsorption to “computationally hard” multiple-Li-ion-adsorbed configuration located at global minima for insight finding and rapid screening. Leveraging this large dataset, we also develop crystal-graph-based machine learning models for the accelerated discovery of potential candidates. A reactivity test with commercial electrolytes is further performed for wet experiments. Our holistic approach, which predicts both Li-ion storage and supercapacitive properties and hence identifies various important electrode materials that are common to both devices, may pave the way for next-generation energy storage systems.

Mechanical energy released during stirred grinding promotes the polymerization reactions of styrene monomers on calcium carbonate and those of polystyrene on titanium dioxide surfaces and makes the surface modification by polymer grafting more efficient and with less initiating agent. Polymer grafting modification activated by mechanochemical effects improves the compatibility of calcium carbonate filler with the polymer matrix and the fluidity of alkyd varnish with modified titanium dioxide as the paint material. The process of polymer grafting modification activated by mechanochemical action and the changes of application properties of materials filled with modified powders are described, the interactions between the modifying agents and the surface of the powders is discussed.

The dispersion of a solid particle in a liquid may lead to the formation of solvation film on the particle surface, which can strongly increase the repulsive force between particles and thus strongly affect the stability of dispersions. The solvation film thickness, which varies with the variation of the property of suspension particles and solutions, is one of the most important parameters of the solvation film, and is also one of the most difficult parameters that can be measured accurately. In this paper, a method, based on the Einstein viscosity equation of dispersions, for determining the solvation film thickness of particles is developed. This method was tested on two kinds of silica spherical powders (namely M1 and M2) dispersed in ethyl alcohol, in water, and in a water-ethyl alcohol mixture (1:1 by volume) through measuring the relative viscosity of dispersions of the particles as a function of the volume fraction of the dry particles in the dispersion, and of the specific surface area and the density of the particles. The calculated solvation film thicknesses on M1 are 7.48, 18.65 and 23.74 nm in alcohol, water and the water-ethyl alcohol mixture, 12.41, 12.71 and 13.13 nm on M2 in alcohol, water and the water-ethyl alcohol mixture, respectively.