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Campelo et al reported that hydroisomerization and hydrocracking of n-dodecane over Pt/SAPO-11 occur inside the catalyst pores, being governed by carbenium-ion chemistry in which shape selectivity imposed by the SAPO-11 structure strongly affects the product distribution [4].
SAPO-11 crystal has the AEL structure and consists of non-intersecting elliptic 10-membered ring pores with 0.39 nm×0.63 nm diamerters [5].
The diffraction peaks indexed in Fig. 2 indicate a SAPO-11 structure for both samples [10].
It is clear that L-A, L-B, L-C and L-D exhibit a spindly morphology, and the crystal structures are substantially affected by the degree of ion-exchange and calcination.
The crystal structure of L-D which was got by thrice ion-exchange and thrice calcination are destroyed partially.

However, the conductivity of LiMn2O4 can be affected by phase transformation between cubic (Fd-3m) and orthorhombic (Fddd) structure which occurs near room temperature.
The structure distortion is visible in the X-Ray pattern as splitting of sensitive reflections.
The most reliable method for investigation of structure-property relationships is to perform simultaneous (in-situ) measurements.
For in-situ study of electrical properties and crystal structure of lithium manganese spinels in course of temperature treatment, a dedicated experimental set-up was constructed.
Samples obtained by sol-gel method and heat-treated at 800ºC (SH and DH) exhibit phase transition from cubic to orthorhombic structure upon cooling below room temperature.

For example, Xiao yan Pana and Xue ming Ma studied the structure of TiO2 powder with different grain size attained by ball milling method[9].
The morphologies and structures of the samples were characterized by scanning electron microscope (SEM) and X-ray diffraction(XRD).
The morphologies and structure of samples were characterized by scanning electron microscope(SEM) and X-ray diffraction(XRD).
Results and discussion As-received commercial TiO2 presents in large structure and agglomeration in micron scale.
Gengyu, The preparation of coupled SnO2/TiO2 photocatalyst by ball milling, Materials Chemistry and Physics 98 (2006) 116–120 [7] M.

The effects of each component on the structure and performance of the chitosan film were studied.
Section structure diagram of the membrane.
It can be seen that the essential oils can be more evenly embedded in the composite membrane network structure without obvious aggregation.
(3) The tomographic structure of the membrane was observed with a scanning electron microscope (SEM).
Journal of Agricultural and Food Chemistry, 2018,66(2):395-413

The big advantage of these materials is their oxide structure – oxidic materials are ideal candidates for thermoelectric conversion.
A strong exothermic reaction is creating a black powder containing the oxide precursor of the required structure.
The evaluation of the crystallographic structure was done by Highscore programme.
The synthesis with decreasing amount of calcium carbonate (5 wt. %) showed the evanescence of free lime and the presence of Ca-Co-O structures with higher level of crystallinity.
The Rietveld analysis of powders cannot be performed because of missing model of main Ca3Co4O9 structure.

Yaropolov1 a 1 Department of Chemistry, Lomonosov Moscow State University, 119899 Moscow, Russia a E-mail: anikina@hydride.chem.msu.ru Keywords: Intermetallic Compound (IMC), Hydride, Thermodynamic, Calorimetry, Ce6Ni1.67Si3-H2 system Abstract.
The authors defined that a new compound crystallized in its own structure type: Ce6Ni2Si3 (space group P63/m, a=1.211 nm, c=0.432 nm) [2].
Kharchenko, Crystal structure of Ce6Ni2Si3 and related compounds, Crystallogr.
Jeitschko, Lanthanum Nickel Silicides with the General Formula La(n+1)(n+2)Nin(n-1)+2Sin(n+1) and Other Series of Hexagonal Structure with Metal: Metalloid Ratios Close to 2:1, Inorg.
Verbetsky, Structure and magnetic properties of RNi (R=Gd, Tb, Dy, Sm) and R6Ni1.67Si3 (R=Ce, Gd, Tb; M=Ni, Co) hydrides, J.

The carbon-adsorb auto combustion method was a good powder prepared technology which use of the activated carbon can adsorb anions and cations from the solution,due to the special geometry structure and chemical properties of the activated carbon surface, and then the nanoparticles obtained through dryness process and thermal treatment.
The reaction mechanism of carbon-adsorb The adsorption of activated carbon mainly come from the inhomogeneous geometry structure and chemical properties of the activated carbon surface.
The main component of activated carbon is carbon, but there are some oxygen, hydrogen and small amounts of other elements which combined by chemistry.[13]So there are both acidic groups and alkaline groups on the surface of the activated carbon in the solution.
The lattice constant of the products:a=8.337,b=8.337,c=8.337 which indicated that the NiFe2O4 was pure spinel structure.
Fig.2.SEM images of the NiFe2O4 nanoparticles The morphology and structure of the as-prepared sample were characterized by SEM and TEM.The SEM images of NiFe2O4 is shown in Fig.2.

ZrB2 ceramic is very difficult to sintered because of the coexistence of metallic bond and covalent bond in its structure.
Generally, the gel structure is built by the Zr-O bonds and B-O bonds [10-11] which are so delicate that the continuity can be severely disturbed by strong concentration and chemistry environment of the sol.
Meanwhile, H3BO3 reacted with sorbitol [13-14] to yield a 3D B-O network structure as Eq.3 showed.
Due to the existence of weakly hydrogen bonds in the Zr-O network structure, water vapor molecules and other small molecules can easily destroy the gel structure which block complete xerogel forming.
The zirconia is not existed in the sample of sol-gel method using zirconium nitrate because there is no inhomogeneous distribution of C caused by extra solidify structure.

Many physical phenomena encountered in science and engineering can be described mathematically through partial differential equations (PDE) and ordinary differential equations (ODE) such as propagation phenomena, engineering applications, hydrotechnics, chemistry, pollution a.s.o.
The structure is porous.
Table 1 CASE u0 [W] tf [s] sf [mm] ytf,s0 [°C] ytf,sf [°C] A2 M3 70 0,5 1 1000 700 M4 60 0,3 0,7 600 400 A3 M1 100 0,5 0,4 850 600 M2 100 0,5 0,4 520 350 By introducing these initial technological dates in the general program SINTER 1(2), for each sample we obtain the structure parameters T1, T2, S1 and S2, the weighting coefficients σ0, σ1 and σ2 and the proportionality coefficient (Ky), shown in Table 2.
Conclusions The sintering process can be described mathematically through partial differential equation of second order (PDE II ⋅ 2) in relation with two independent variables, representing the time (t) and space (s), providing many degrees of freedom by the structure parameters (T1, T2, S1, S2) , the weighting coefficients (σ0,σ1,σ2) and the proportionality coefficient (Ky), defined in Eq. 3.

%Si should form a completely eutectic structure.
%Si alloy solidified under high pressure presented a finely clump structure rather than the coarse lath-shaped structure of alloys solidified under normal pressure. 3.4 Effect of pressure on the morphology of eutectic structure in the Al-Si alloy Fig. 4(a) shows the SEM micrograph of the eutectic structure of Al-13at%Si alloy solidified under normal pressure; the sample was processed by heavy etching to remove the Al phase and retain only the Si phase in the eutectic region.
The microstructure is a complicated net-like structure composed of acicular eutectic Si phase branches with no definite spacing between the layers.
Thus, the solidified structure was intercrossed, and the eutectic cell was hardly evident.
Crystal growth followed a parallel lamellar pattern around this center until they touched each other and formed the rosette eutectic cell structure.