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Speciation analysis of harmful elements in the scheelite tailings Ziqiang Gu1a Xuqing Liu2b Ke Xiang2c Xuan Qin3d Yayun Li2e 1Environmental protection monitoring station of Shangrao City, Jiangxi Province Shangrao,Jiangxi 334000 2College of chemistry and environmental engineering,Wuhan Institute of Technology Wuhan,Hubei 430073 3 Hubei Environmental Science Research Institute, Wuhan,Hubei 430072 asrsgzq123@126.com,blxqkyq1997@163.com,c512166620@qq.com, d52407554@ qq.com, e594998782@qq.com Keywords: Skarn type scheelite; mine tailings; harmful elements; the exchangeable speciation; the residual speciation Abstract.
d.The residue speciation Tailings in residue form is mainly some silicate minerals.Because the form of mineral crystal structure, size and other factors can have a stronger adsorption to the heavy metal elements,therefore it belongs to a relatively stable state in the environment.Levels of the harmful elements in residual state could get from the total amount of the corresponding elements in the tailing samples subtract the results from the results above.
The morphology and characteristics of arsenic in the tailings The residue state of arsenic in the tailings samples is up to 66.23%,but the exchangeable state with strong activity is only 5.69%,the reason may be the the lattice structure of arsenic in ore is ARSENOPYRITE,and it is relatively stable in the process of ore dressing,thus the arsenic in the tailings is also stable.
c.The residue state of arsenic in the tailings samples is up to 66.23%,but the exchangeable state with strong activity is only 5.69%,the reason may be the the lattice structure of arsenic in ore is ARSENOPYRITE.

Among various technologies and architectures to overcome the obstacle, Si films with some special structures, such as silicon nanowire, was proposed and exihibit good performance [4] .
After standard photolithography processes and anodic oxidation in the photo-assisted electrochemical etching systems, the Si-MCP with a uniform and stable structure was formed [6, 7].
It indicates that the copper grain is the surface-centered cubic structure.
Physical Chemistry C.

During hydration of these materials the zeolite-like structure origins.
Real structure is quite complicate to describe.
Hydrated structure is made almost from calcium silicate hydrate phase of Tobermorite type [8, 9].
[6] Davidovits, J., Geopolymer chemistry and applications, Geopolymer Institute, 2008

Bone is a connective tissue with a unique hierarchical organization and composite organic-inorganic structure that allows load bearing and serves as a protection of several soft organs.
This balance is fundamental to retain a healthy bone tissue structure, but several factors influence this balance, including aging and change in hormonal balance or pathology.
Deposition of such functionalized nAp requires a method that can preserve the structure and the activity of alendronate.
Analytical Chemistry 71 (1999) 1415-1420

The structure of the obtained flame retardant coatings was evaluated using an optical microscope.
Fire resistance of reinforced concrete and steel structures.
Fire resistance of reinforced concrete and steel structures, 1-166
Organophosphate flame retardants in the environment: Source, occurrence, and human exposure, In Comprehensive Analytical Chemistry. 88, 341–365
Journal of Materials Chemistry.

Zu1,g 1Department of Applied Physics, University of Electronic Science and Technology of China, Chengdu 610054, China 2Department of Physics and Engineering Technology, Sichuan University of Arts and Science, Dazhou 635000, China 3Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang 621900, China aftkjm@yeah.net, byanglilkd@yahoo.com.cn, cpengshuming@hotmail.com, dlongxinggui@hotmail.com, ewlzc@yahoo.com.cn, gxiaotqaozu@yahoo.com Keywords: Bond-order potential; hcp-scandium.
The self-interstitial atom (SIA) formation energy, the properties of the face-centered cubic (fcc), body centered cubic (bcc), simple cubic (sc) and diamond structures of scandium are also tested using the fitted parameters and listed in Table 2.
DFT predicts the Bo to be the most stable, while the Bc structure is the most stable for Hu potential.
At the same time the structural stability of the real hcp lattice relative to fcc, bcc, sc and diamond structures was also tested.
Massalski: 1980 Structure of Metals 3rd edn (Oxford: Pergamon), p. 626 [12] R.

X-ray diffraction studies were conducted to determine the crystal structure with a Philips PW3710 diffractometer using CuKα radiation at 35 kV and 25 mA.
One can see that (100), (002), (101) peaks of hexagonal structure (JCPDS 36-1415) appears, no preferential orientation exhibited.
The films are crystalline and exhibit the hexagonal structure with the three important peaks in the recorded range identified.
Chemistry of Materials. 2004; 16: 2965-2968
Effect of coupling structure of Eu on the photoluminescent characteristics for ZnO:EuCl3 phosphors [J] Appl Phys Lett 1998, 72: 668-670

According to the conducted researches [10, 11] the structure of fine concrete, first of all formed by granules of small filler is capable to reach the best indicator only in case of application of sand Large (FR. 2.5-3.0) and Increased size (FR. 3.0-5.0), corresponding to the requirements.
References [1] Rozental N.K., Chekhniy G.V., The reasons for the formation and methods of preventing the formation of efflorescence on the surface of building structures, Proceedings of the 1st All-Russian Conference on Concrete, Moscow, 2001, pp. 1444- 1447 [2] Babkov V.V., Klimov V.P., Sakhibgareev R.R., Chuikin A.E., Mechanisms of efflorescence on surfaces of external walls of buildings from a piece of wall materials, Magazine of Building materials. 8 (2007) 74-76
[4] Babkov V.V., Gabitov A.I., Chuikin A.E., Features of salinization on the surfaces of the external walls of buildings erected in winter conditions on the basis of piece wall materials, Bashkir Chemistry Journal. 5 (2007) 156-159
[8] Stepanova V.F., Rozental N.K., Chekhniy G.V., Reasons for the formation of efflorescence on the surface of building structures, Building materials, equipment and technologies of the XXI century. 3 (2000) 12-13
D., Influence of fine-grained concrete structure on the main technical properties, Concrete Technology. 2 (2013) 16-17

Magnesium alloys exhibit, however, low ductility near room temperature due to their limited number of active slip systems having a HCP crystal structure.
Addition of solute elements to pure magnesium can improve the formability either by reducing the axial ratio (c/a) or by transforming the hexagonal crystal structures into a cubic structure.
Reducing the axial ratio of HCP structures can be accomplished through the addition of alloying elements, which occupy the substitutional sites of the crystal lattice.
Pearson: The Crystal Chemistry and Physics of Metals and Alloys (Wiley-Interscience, New York, 1972)

The precise structure and polymorphs of the biominerals are controlled by a small amount of bio-macromolecules, such as proteins and polysaccharides, contained in the minerals [2,3].
In copoly[Ser(P) x Aspy ] (x : y = 75 : 25, 50 : 50, 25 : 75), the spherical vaterite (Fig. 1b), the epitaxial calcite (Fig. 1c) and the helical structure with a clockwise P twined spiral morphology (Fig. 1d) were obtained.
Most interestingly, when the Ca 2+/copoly[Ser(P) 75 Asp 25 ] residue molar ratio in the mixed solution was 10, a CaCO3 helical structure with a clockwise P twined spiral morphology was obtained (Fig. 1d).
The helical crystals were calcite and had a regular repetition structure.
Mann: Biomineralization: Principles and Concepts in Bioinorganic Materials Chemistry (Oxford Univ Press, UK 2001)