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The microflotation of three single minerals, mixed coal–kaolinite and mixed coal–montmorillonite were examined to study the effects of clay and calcium ions on coal flotation. The results show that the ash content of flotation concentrate increases by 3% in the presence of clay minerals, and the ash content would further increase by 3% in co-presence of clay minerals and high concentration of Ca2+. Scanning electron microscope (SEM) images and elemental spectrum analysis indicate that fine clay particles that coat on the coal surface, which is called slime coating, can affect the coal flotation. The slime coating would be induced much more easily in the presence of Ca2+. Keywords: Microflotation, Clay, Calcium ions, Slime coating

An experimental research on magnetic concentrate of a hematite using the anionic reverse flotation technology in the flotation column was conducted. Through systematic studies in the lab, the optimal technological and operational conditions had been obtained as follows: the circulation pressure of 0.055 MPa, the feeding quantity of 160 g/min, the collector dosage of 800 g/t and the starch dosage of 900 g/t. The results show that the iron concentrate with grade of 67.37% can be achieved according to the flow sheet of one roughing and one scavenging under the optimal conditions, and also reflects the advantages of excellent selectivity and high recovery. The application of cyclonic static micro-bubble flotation column in hematite reverse flotation provides a new approach for hematite reverse flotation in China.

This paper made deep studies on chlorite flotation using anionic/cationic collector, and the following effect factors such as pH,Ca 2+ ,Na 2 S,NaF,Na 2 SiF 6 and (NaPO 3 ) 6 are investigated. In the process of chlorite flotation using oleic acid as anionic collector, pH value increases. The concentration increase of Na 2 S and NaF can activate the chlorite flotation. However, Ca 2+ , Na 2 SiF 6 and (NaPO 3 ) 6 can depress the chlorite flotation. In the process of chlorite flotation using lauryl amine as cationic collector, the maximum recovery of chlorite flotation happened in neutral pH condition, and the concentration increase of Ca 2+ can activate the chlorite flotation; however, NaF and Na 2 SiF 6 can depress the chlorite flotation.

Qianjiaying coke coal slime is extremely difficult to float. Conventional flotation process leads to a massive waste of high quality coal. In this paper, raw coal slime and rough separation concentrate are grinded to improve separation effect. Coal slime grinded directly through rough-cleaning process can get concentrate rate of 52.87% and concentrate ash of 11.27%. In the rough concentrate grinding process, concentrate ash drops to 10.74%, when the concentrate accumulation rate reaches up to 55.53%. Compared with the coal slime direct floatation, the concentrate rate was enhanced by 4.66%, and the ash was decreased by 1.02%. Besides, in the regrinding of middlings flotation, the concentrate rate reaches as high as 68.35% and ash rate is only 11.51%, the production efficiency is greatly improved.

Nano-Sb2O3/mica flame retardant composition is synthesized by colloidal and assembling techniques. The morphology and assembled behavior of nano-Sb2O3 on mica are analyzed by means of X-ray powder diffraction (XRD) and transmission electron microscopy (TEM). The flame retardant properties and mechanism of nano-Sb2O3 and nano-Sb2O3/mica composition are studied by combustion test, thermogravimetric (TG) analysis, and differential scanning calorimetry (DSC). The results show that the nano-Sb2O3 particles assembling in nano-Sb2O3/mica composition distribute on the mica surface with smaller size (about 5 nm), higher dispersivity, narrower size distribution and alike shapes, compared with nano-Sb2 O3 prepared by the normal method. The nano-Sb2O 3/mica composition has achieved the same synergistic effects with chlorinated paraffin as nano-Sb2O3, and its flame retardant properties have been improved prominently through decreasing the temperature and combustion reaction rate of the polymer effectively and forming char. When the FRP sample contains about 7wt% nanocomposition (i.e., containing about 0.8 wt% mica), it is self-extinguished once departing from the fire while combusting.

With the devepment of network and multimedia technology, the network and multimedia teaching have become a kind of teaching means with high-efficiency and good effects. The physical chemistry network teaching system adopting XHTML+ CSS+ASP+java-script+XML+ACCESS techniques has built a kind of Web platform based on data,which can satisfy the physics chemistry teaching course, remote learning, the teaching-studing interaction and so on. The pages were formed by DIV+CSS techniques to separate surface layer from structure layer. The system is composed of eight parts including school teaching system, experiment coach, tutorship answer, homework exercises, graduate garden plot, field development, remote teaching, hotspot links and six assistant parts. It is designed and presented using website with the text, picture, flash, video and so on. The system is characterized with easy use and management, extremely expansivity, stability, safety, high-efficiency and so on.

Mineral processing plant design curriculum is innovated ceaselessly so as to improve the education quality and to bring students up the engineering diathesis and design competence through the courses, teaching material, experiment, practice in plants, and scientific research. The computer multimedia technic plays a important role in the curriculum innovating. In practice, a serial research, named APPLYING COMPUTER MULTIMEDIA TO A SET OF TEACHING LINKS is carried out. The computer multimedia is applied to compiling the teaching material, classroom teaching, classroom-work, practice after classroom, graduation project and second classroom, which have made great progress.

A broad band polarization-independent reflector working in the telecommunication C+L band is proposed using the guided mode resonance effect of a periodic surface relief element deposited by a layer of silicon medium. It is shown that this structure can provide high reflection (R > 99.5%) and wide angular bandwidth (θ ≈ 20°, R > 98%) for both TE and TM polarizations over a wide spectrum band 1.5 μm~1.6 μm. Furthermore, it is found by rigorous coupled wave analysis that the polarization-independent reflector proposed here is tolerant of a deviation of grating thickness, which makes it very easy to fabricate in experiments.