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This article describes the characteristics of natural dusts, industrial dusts, and artificial dusts, such as mineral phases, chemical components, morphological observation and size. Quartz and calcite are the main phases of natural dusts and industrial dusts with high SiO2 and CaO and low K2O and Na2O in the chemical composition. The dissolution and electrochemical action of dusts in glutamic acid liquor at the simulated human body temperature (37 °C) in 32 h was investigated. The potential harm that the dust could lead to in body glutamic acid acidic environment, namely biological activity, is of great importance for revealing the human toxicological mechanism. The changes of pH values and electric conductivity of suspension of those dusts were similar, increased slowly in the first 8 h, and then the pH values increased rapidly. The total amount of dissolved ions of K, Ca, Na, and Mg was 35.4 to 429 mg/kg, particularly Ca was maximal of 20 to 334 mg/kg. The total amount of dissolved ions of Fe, Zn, Mn, Pb, and Ba was 0.18 to 5.59 mg/kg and in Al and Si was 3.0 to 21.7 mg/kg. The relative solubility order of dusts in glutamic acid is wollastonite > serpentine > sepiolite, the cement plant industrial dusts > natural dusts > power plant industrial dusts. The wollastonite and cement plant industrial dusts have the highest solubility, which also have high content of CaO; this shows that there are a poorer corrosion-resisting ability and lower bio-resistibility. Sepiolite and power plant industrial dusts have lowest solubility, which also have high content of SiO2; this shows that there are a higher corrosion-resisting ability and stronger bio-resistibility.

Effects of particle size and chain length on flotation of quaternary ammonium salts (QAS) onto kaolinite have been investigated by flotation tests. Dodecyltrimethylammonium chloride (DTAC) and cetyltrimethylammonium chloride (CTAC) were used as collectors for kaolinite in different particle size fractions (0.075 ~ 0.01 mm, 0.045 ~ 0.075 mm, 0 ~ 0.045 mm). The anomalous flotation behavior of kaolinite have been further explained based on crystal structure considerations by adsorption tests and molecular dynamics (MD) simulation. The results show that the flotation recovery of kaolinite in all different particle size fractions decreases with an increase in pH. As the concentration of collectors increases, the flotation recovery increases. The longer the carbon chain of QAS is, the higher the recoveries of coarse kaolinite (0.075 ~ 0.01 mm and 0.045 ~ 0.075 mm) are. But the flotation recovery of the finest kaolinite (0 ~ 0.045 mm) decreases with chain lengths of QAS collectors increasing, which is consistent with the flotation results of unscreened kaolinite (0 ~ 0.075 mm). It is explained by the froth stability related to the residual concentration of QAS collector in mineral pulp. In lower residual concentration, the froth stability becomes worse. Within the range of flotation collector concentration, it’s easy of CTAC to be completely adsorbed by kaolinite in the particle size fraction (0–0.045 mm), which led to lower flotation recovery. Moreover, it is interesting that the coarser particle size of kaolinite is, the higher flotation recovery is. The anomalous flotation behavior of kaolinite is rationalized based on crystal structure considerations. The results of MD simulations show that the (001) kaolinite surface has the strongest interaction with DTAC, compared with the (001) face, (010) and (110) edges. On the other hand, when particle size of kaolinite is altered, the number of basal planes and edge planes is changed. It is observed that the finer kaolinite particles size become, the greater relative surface area of edges and the more the number of edges are. It means that fine kaolinite particles have more edges to adsorb fewer cationic colletors than that of coarse kaolinite particles, which is responsible for the poorer floatability of fine kaolinite.

A series of compounds with the general formula Gd2-xNdxZr2O7 (0.0 ≤ x ≤ 2.0) was synthesized by high- temperature solid state method and characterized by powder X-ray diffraction. Trivalent neodymium was used as the surrogate for americium with three valences, an actinide found in radioactive nuclear wastes. The X-ray diffraction patterns show that the whole system of Gd2-xNdxZr2O7 (0.0 ≤ x ≤ 2.0) consistently possesses the pyrochlore structure. In order to get the accurate data of structural changes of zirconate pyrochlores incorporating Am3+, the Rietveld structural refinement method was employed to calculate the crystal cell parameters of zirconate pyrochlores. The calculated results indicated that the value of x in the system Gd2-xNdxZr2O7 (0.0 ≤ x ≤ 2.0) and the crystal cell parameter a accord with a = 10.52696 + 0.07036 x, x and the volume of crystal cell V follow the relation of V = 1166.45459 + 23.72163 x.

Tourmaline from Altai mine in China's Sinkiang was used to remove lead (II), copper (II) from aqueous solution. The results demonstrate that tourmaline contains Na(Mg,V)3Al6(BO3)3Si6O18(OH)4, NaFe3Al6(BO3)3Si6O18(OH)4. The data show that Tourmaline from Altai mine in China's Sinkiang can be used natural adsorbent for lead (II), copper (II). It is observed that the adsorption data fitted to the Langmuir isotherm. Furthermore, both Pb (II) and Cu (II) absorbed by tourmaline and tourmaline were characterized by X-ray diffraction, Laser Raman Spectrum, Fourier transform infrared spectroscopy, X-ray energy dispersive spectrometer, Transmission electron microscopy and Zeta potential.

In order to study the damage mechanism of mineral dusts on the pulmonary alveolar macrophage (AM), the changes in their death ratio, malandialdthyde (MDA) content and activities of lactate dehydrogenase (LDH) and superoxide dismutase (SOD) were measured, and the technique of cell culture in vitro was used to investigate the cytotoxicity of six mineral dusts (twelve crystal habits) from twelve mineral deposits. The results show that wollastonite and clinoptilolite have no AM cytotoxicity, while other fibrous and grainy mineral dusts damage pulmonary AM in various degrees. The cytotoxicity of fibrous mineral dusts was greater than that of the grainy ones, and the cytotoxicity of dusts was positively correlated with the active OH content in dusts, but not necessarily so with its SiO2 content. The high pH values produced by dust was unfavorable for the survival of cells and the dusts with low bio-resistance were safe for cells. The content of variable valence elements in dusts might influence their cytotoxicity and the surface charge of dusts was not a stable factor for their toxicity. It is demonstrated that the shape of mineral dusts was one of the factors affecting cytotoxicity, and that the cytotoxicity of mineral dusts depends mainly on their properties.

In order to compare the chemical compositions and physical properities of dusts on silicate bacteria S35, the chemical compositions of six kinds of mineral dusts have been analyzed and the changes of pH value, glucose (GLU), electrolyte and Mn, Si, Fe before and after the dusts reacted with silicate bacteria S35 have been measured. The SEM analysis has been used to study the bacterial form and interface action status in the course of reaction between dusts and bacteria. The results show that these mineral dusts have different effects on experiment bacteria. Therefore, it is concluded that the effect of mineral dusts on silicate bacteria has correlation with the chemical compositions and physical properities of dusts.

The exposed and transformed groups of fibrous brucite, wollastonite, chrysotile asbestos, sepiolite, palygorskite, clinoptilolite, crocidolite and diatomaceous earth mineral materials are analyzed by IR spectra after acid and alikali etching, strong mechanical and polarity molecular interaction. The results show the active sites concentrate on the ends in stick mineral materials and on the defect or hole edge in pipe mineral materials. The inside active site of mineral materials plays a main role in small molecular substance. The shape of minerals influence their distribution and density of active site. The strong mechanical impulsion and weak chemical force change the active site feature of minerals, the powder process enables minerals exposed more surface group and more combined types. The surface processing with the small polarity molecular or the brand of middle molecular may produce ionation and new coordinate bond, and change the active properties and level of original mineral materials.

The kinetics of biosorption and desorption to lead ions on dried and wet wasted beer yeast were investigated with the instruments of AAS and SEM. In order to enhance the experimental results reliability and practice application value, the sorption solution system was gone on i°Li±-degree dosage level in the whole experimental process. The results showed that the biosorption and desorption process were fast to Pb2+ on dried and wet beer yeast. There were very good biosorption or desorption effect in the first 30 min, and in this time, the desorption efficiency was 91.70% and 82.93% to dried and wet beer yeast, respectively. In the first biosorption process, wet beer yeast had better biosorption effect than dried beer yeast. In addition, desorbent of 0.1 mol/L HNO3 was considered that it couldni¯t use as the best desorption condition. The other desorption conditions were need research or the beer wasted beer yeast is only used for single-time biosorbent.

In order to compare the chemical compositions and physical characteristics of different atmosphere dusts on S. epidernidis, chemical compositions of five kinds of atmosphere natural dropping dusts have been analyzed and the changes of pH value, glucose (GLU), electrolyte before and after the dusts reacted with S. epidernidis have been measured. The SEM analysis has been used to study the bacterial surface morphology and interface action status in the course of reaction between dusts and bacteria. The results illustrated that Major chemical composition of atmosphere dusts and dissolution quantity of ions after the aced with S. epidernidis were different. The atmosphere dusts containing high Ca2+ or Mg2+ could increase the number of S. epidernidis and the use quantity of GLU. The dust granules’ adhered degree is increasing with the granularity’s decreasing, and the abnormity figure could increase the adhering degree between the bacterial membranes and dust surfaces.

The biosorption of Pb(II) ions on dried wasted beer yeast was investigated with respect to the adsorption conditions. The results of this study indicated that different variables, such as contact time, adsorbent dose, solution pH and initial heavy metal ions concentration influenced the adsorptive quantity. The best adsorption parameters and quantitative analysis of Pb2+ by dried waste beer yeast revealed that at optimum conditions (pH = 4.5; Pb2+ initial concentration = 1.0 mmol/L; biomass dose = 4.0 g/L; contact time = 90 min), the highest metal uptake values obtained above 60 mg/g and the adsorptive efficiency was above 93%. The SEM analysis showed that the interactions between Pb(II) ions and functional groups on the cell wall surface of dried waste beer yeast. Consequently, dried waste beer yeast is an inexpensive, readily available adsorbent for metals and especially has a high adsorption capacity for Pb(II) ions.