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The crystalline structure and chemistry of nano- and microcrystalline alloys were examined by the methods of X-ray diffraction.
a b a b Fig.5 Histogram of the size distribution of grains Fig.4 The surface structure of nanocrystalline Y35Fe65 alloys, obtaining by methods of optical microscopy (80х80 mm)(a) and atomic force microscopy (0.5x0.5 mm)(b) Fig.3 The surface structure of nanocrystalline Y25Fe75 alloys, obtaining by methods of optical microscopy (80х80 mm) (a) and atomic force microscopy (1x1 mm)(b) On the second stage rapidly quenched samples were manufactured by melt spinning method.
Figure 3 and figure 4 show the surface structure of nanocrystalline ribbons of Y25Fe75 and Y35Fe65 alloys.
Ribbons have microscale structure consisted of intermetallic crystals with an average grain size of about 5 microns, the crystals in turn, have a very uniform substructure with characteristic dimensions of several tens of nanometers.
Besides, it is shown that formation of nanoscale structure does not affect on the ratio of the phase in the cast and rapidly quenched samples.

Introduction The porous structure of HAp provides a template for fibrovascular ingrowth, which is followed by osteoblast differentiation that results in the deposition of new lamellar bone [1,2].
Fig.5 The FT-IR spectrum of the coating A: apatite; T: titanium Conclusions Porous titanium of different structures can be fabricated by the use of the method presented.
The results of this study presents an effective method to obtain coatings on the porous structure.
Accordingly, the geometry and structure of fabricated substrates can modulate the growth of the biomimetic apatite coatings.
Physical chemistry (1988).

Here is the structure of the PCS experiment.
Fig.3 is the structure of the first kind photon counter.
Fig.3 The structure of the first kind photon counter The second kind photon counter is divided into three parts.
Fig.4 is the structure of the second kind photon counter.
Photo-physics and Laser Chemistry.B42(1987):p193-213

The host metabolism, mechanical factors and implant structure and chemistry can be determinant to bioprosthetic valve calcification.
Therefore, there is no way to infer that different structures are being formed in each of the two types of cardiac valves that were analyzed in this study, since the Ca/P ratios were similar in both samples and the different morphology could be caused by the condition in which each sample surface was submitted before analyses.
Fine X-ray structure analyses are underway to investigate the crystal structure of the calcium phosphate deposits and therefore analyze the possible differences among the structure of these samples.
Further studies will indicate whether the formed compounds have also similar chemical and crystallographic structures.

Chemical Structure Changes and Correlation Analysis of High Density Polyethylene after Natural and Xenon Aging Jun-jun GUO1, a, Hua YAN1,b, Zhi-de HU1,c, Jian-jian YANG1,d 1 Dept. of Chemistry & Material, Logistic Engineering University, Chongqing 401331, China agu7yu@126.com, byanhuacq@sina.com, chuzd6503@163.com, dyangjianjiancq@163.com Keywords: Natural aging; Xenon aging; Chemical structure; Correlation; ATR-FTIR.
Elucidation of the chemical structure changes that take place of high density polyethylene (HDPE) used as rotational packaging case by attenuated total reflection infrared spectroscopy (ATR-FTIR), when natural aging of Lasa Tibet and xenon aging.
The branching degree depend on linear structure of molecular chain related to the melting point, tensile mechanical property, cell parameters, crystallinity and other physical property.
The crystallinity is a vital parameter of crystal structure closely linked to young modulus, hardness, chemical resistance and other physicochemical properties [15].
On one hand the micro-molecule produced by degradation is active to have secondary crystallization along original grain structure, which increase the crystallinity, on the other hand the oxidation products generated in chain structure will disrupt the regularize crystal structure decreasing the crystallinity.

Toshima, Novel synthesis, structure, and oxidation catalysis of Ag/Au bimetallic nano particles, The Journal of Physical Chemistry, 114 (2010) 10336–10341, doi: 10.1021/jp9119149
Rivero, Effect of the Alumina shell on the melting temperature depression for Aluminum nanoparticles, The Journal of Physical Chemistry C, 113 (2009) 14088–14096, doi:10.1021/jp902317m
Zhao, Size-dependent melting point of noble metals, Materials Chemistry and Physics, 82 (2003) 225–227, doi.org/10.1016/S0254-0584(03)00201-3
Mori, Effect on substrates on the melting temperature of gold nano particles, Computer coupling of Phase Diagram and Thermo chemistry, 31 (2007) 105-111, doi:10.1016/j.calphad.2006.10.001
Kumar, Effect of size and shape on melting and superheating of free standing and embedded nanoparticles, Journal of Physical and Chemistry of Solid, 106 (2017) 112-117, doi.org/10.1016/j.jpcs.2017.03.010

Green Chemistry, 14 (2012) 1073-1078
Chemistry–An Asian Journal. 4 (2009) 1050–1054
Chemistry Res. 47 (2008) 6081–6090
Journal of Industrial and Engineering Chemistry, 2(2014) 739-744
Materials Chemistry and Physics, 128 (2011) 83-89

In addition, many researchers made the sewage sludge into adsorbent material by means of the porous structure [4,5].
References [1] Biarne.P, Kjell.T.N.W, Science Technology, 36, 283-290. (1997) [2] Bengtsson.M, Tillman.A, Resources, Conservation and Recycling, 42, 65-82. (2004) [3] Fytili.D, Zabaniotou.A, Renewable and Sustainable Energy Reviews, 12, 116-140. (2008) [4] Yu Lan-lan, Qin zhong, Environmental Chemistry, 24, 401-404. (2005) [5] P.C.Chiang, J.
M, Analytical Chemistry, 51, 844-851. (1979) [11] A.M.URE, P.Q, H.MUNTAU, B.GRIEPINK, Intern.J.Environ.Anal.Chem, 51, 135-151. (1992) [12] I.

Submicrometric iron particles for the removal of pharmaceuticals from water: Application to b-lactam antibiotics Antoine Ghauch1,a, Habib Baydoun1,b, Al Muthanna Tuqan1,c, Ghada Ayoub2,d, Sahar Naim2,e 1 American University of Beirut, FAS, Chemistry Dept.
Box 11-0236 Riad El Solh, Lebanon 2 Lebanese University, Faculty of Sciences, Chemistry Dept.
Accordingly antibiotics are progressively enmeshed in the structure of nascent adsorbents.

Scale-up of Wet Precipitation Calcium Phosphate Synthesis Marina Sokolova1,a, Andris Putnins1,b, Imants Kreicbergs2,c and Janis Locs1,d 1Rudolfs Cimdins Riga Biomaterials Innovation and Development Centre, Riga Technical University, Pulka Str. 3/3, Riga, LV-1007, Latvia; 2Riga Technical University, Faculty of Materials Science and Applied Chemistry, Institute of General Chemical Engineering, Azenes Str. 14/24, Riga, LV-1048, Latvia; amarina.sokolova@rtu.lv, bandris.putnins@rtu.lv, cimants.kreicbergs@rtu.lv, djanis.locs@rtu.lv Keywords: calcium phosphates, hydroxyapatite, β-tricalcium phosphate, wet precipitation synthesis, scale-up Abstract.
HAp has similar chemical composition and crystal structure to natural apatite, found in the human skeletal system and is suitable for bone tissue substitution and regeneration [3,4].
Various processes are employed to prepare CaP powders, including mechanochemical synthesis, combustion preparation and various techniques of wet chemistry, such as direct precipitation from aqueous solutions, electrochemical deposition, sol-gel methods, hydrothermal synthesis and emulsion or microemulsion routes [5-7].