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The microstructure presents simple solid solution structure, and the fraction of FCC crystal structure decreased with increasing of Al content.
The phase structure of as-cast samples was characterized by X-ray diffraction(XRD).
Typical cast dendrite(DR) and interdendrite(ID) structures were observed in these high entropy alloys.
With the increasing of aluminum content, FCC solid solution inclines to transform into BCC structure.
Materials Chemistry and Physics,2005,92:112-7

El-Kady1,e 1Faculty of Science, Chemistry Department, Al-Azhar University, Nasr City, Cairo Egypt  2Central Metallurgical Research & Development Institute, P.O.
The XRD analysis showed that all substituted (LNFMO-Mˊ) samples are comported with the main structure of undoped (LNFMO) with crystalline disordered spinel Fd-3m structure.
Both glycine and CTAB were employed as chelating and structure directing agents, respectively.
Crystal Structure Fig. 1 shows the XRD patterns of the prepared LNFMO, LNFMO-Cu LNFMO-Mg and LNFMO-Zn nanopowders.
The suppression of LizNi1-zO2 by Fe-doping in LMNO structure also agrees with previous report [8].

Yoshioka, High oxide ion conductivity in Mg-doped La10Si6O27 with apatite-type structure.
Brendebach, Local atomic structure of a zirconia-based americium transmutation fuel, J.
YSZ crystal structure [26] M.
Tarascon, Defect chemistry and catalytic activity of nanosized Co3O4, Chem.
Zuev, Thermodynamics, defect structure, and charge transfer in doped lanthanum cobaltites: an overview.

Atomic force microscopy (AFM), since its invention, has become a powerful tool for studying surface structures from the micron scale down to the atomic scale.
Mineral content will play a different, more important role since two parameters have to be taken into account: the chemistry of the minerals (more or less resistant to weathering) and the variety and proportion of the components present in the rock.
While texture (including grain sizes and their contours) and porosity define the fluid infiltration an crystal growth, the mineral composition (chemistry and structure) and its diversity will define the capacity to promote reactions, to form new minerals or to expand, causing weakness to the rock structure and accelerating alteration, even disaggregation.
Arliguie: Penetration of chlorides in relation to the microcracking state into reinforced ordinary and high strength concrete, Materials and Structures 31(5) (1998) pp. 310-316
Vogler: Structure and reactivity of water at biomaterial surfaces, Advances in Colloid and Interface Science 74(1-3) (1998) pp. 69-117

The objective of this article is to review on the latest development in the chitin/chitosan extraction methods. 2 Preparation method of chitin/chitosan The structure of chitin and chitosan was showed in figure 1.
Microfiber becoming swelling and results in a loose structure through ultrasonic treatment, which makes the reagent easily permeate so as to achieve a better extracting efficiency.
Additionally, the structures and functions of chitin/ chitosan extracted from bacteria fermentation were similar with those prepared with chemical method.
The chitosan prepared with this method has a high level of deacetylation, but it also result in an uneven deacetylation and destroy the structure of chitosan.
Ajun Wan School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University Shanghai, 200240 E-mail:wanajun@sjtu.edu.cn References [1] S.L.

Lignin is a polyphenolic polymer with an extraordinary structure that is different from other components of wood [2][3].
The structure of lignin diversifies greatly depending on the plant species and the isolation method used [4][5].
It was important to determine such as functional groups, structure, thermal stability and chemical composition of lignin obtained.
The morphology appears a porous structure and the surface composition is dominated by carbon and oxygen elements.
Tshabalala, Cell Wall Chemistry.

Structures of various oxides thin films, such as In2O3, SiO and TeO2 and their mixtures in different proportions were studied.
They determine the optical, electronic and transport properties of the material and usually dominate the chemistry of its surface.
The geometric structure of oxides can go from very simple systems with a NaCl-like structure to complex spinels and perovskites.
According to the XRD data [13], thin films of In2O3 showed cubic In2O3 structure (C-type rare earth structure) with unit cell constant a=10.103 Å.
Fig. 1 shows a micrograph for as-deposited In2O3/SiO thin films, having homogeneous structure, without any imperfections.

CM is composed of both amorphous and crystalline parts and exhibit a web-like structure.
This structure consists of cellulose microfibrils.
However, as the reaction time reaches 4 h, the cell wall structure has a tendency to be destroyed.
This structure can make the obtained CM become a potential reinforcement for composite materials.
Rojas, Cellulose nanocrystals: chemistry, self-assembly, and applications, Chem.

All SEM images of the "as prepared" samples show a bundled structure and confirm the differences in curvature (see figure 2).
On the contrary, the Sn@CNTs sample shows pronounced defects in the CNTs graphitic structure with drastic changes in their curvature.
The unfilled SWCNTs and MWCNTs present, usually, a straighter structure along the axis while the Sn@CNTs show a bended structure in agreement with SEM (shown above) and TEM images (see ref. [8]).
The presence of this state is interpreted as the result of defects presence in the CNTs structure [23] confirming the findings from the SEM, Raman and STM measurements which indicate the presence of a more defective structure. 500 nm 1 nm 1 nm 10 nm 1 2 3 Figure 4.
Journal of Physical Chemistry B 108 (2004) 18908

The Structure of CaS and CaSe has been Rock Salt (B1) at ambient pressure and with increasing pressure Rock Salt (B1) structure undergo a transition in Cesium Chloride (B2) at 40GPa and 38 GPa respectively and CaS1-xSex under goes Rock Salt to Cesium Chloride (B1→B2) structure.
Calcium chalcogenides and their alloy form a very important closed shell ionic system crystallizing in six-fold-coordinated NaCl-type B1 structure at ambient pressure and with increasing pressure B1 structure undergo a transition in eight-fold coordinated CsCl-type B2 structure[4,5,7, 12,13].
Structure of CaS and CaSe has been B1 at ambient pressure and with increasing pressure B1 structure undergo a transition in B2 at 40 GPa and 38GPa.
This model has a promise to predict these properties and phase transition in alloy of other crystal structure as well.
Sanyal 1998 Journal of Physics and Chemistry of solids 59 1633-1637