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Another method of counteracting the natural changes of shrinkage is designing structures involving expansive concrete [1,2,4,7].
Depending on the size of expansion, cements are divided by author into: - non shrinking, in which the process of shrinkage and expansion are in balance, resulting in material with almost zero volume change - show changes of free expansion from 2 to 3 mm/m, - low-expansive, in which expansion exceeds shrinkage, but does not significantly change the stress state of the structure - ease in expansion about 5 to 6 mm/m, - expansive (medium expansive), in which expansion is adjusting stresses in a structure in a desired manner - ease in expansion from 6 to 12 mm/m, - highly expansive (self-compressive-expansive), which may lead to compression of the structure, e.g., causing creation of tensile forces in the reinforcement bars - ease in expansion from 12 to 25 mm/m.
When designing structures using expansive concrete, we can influence the formation of stress distribution.
Kurdowski, Chemistry of cement (in Polish), PWN, Warsaw (2010) [3] Z.
Collepardi, Shrinkage-compensating concretes for special structures, 4th International Conference on Non-Traditional Cement & Concrete, Brno (2011)

Deshmukh4,g* 1Department of Physics, COEP Technological University, Pune 411005, India 2Department of Chemistry, COEP Technological University, Pune 411005 India 3Department of Metallurgy and Materials Science, COEP Tech.
To obtain an orthorhombic structure, high annealing is essential.
X-ray diffraction is used for investigation of solid structure and to confirm the phase purity.
It is observed that in the case of an as-deposited sample, very low intensity peaks corresponding to LFO structure were obtained.
The observed values match well with the JCPDS data card no. 37-1493 which confirms the formation of an orthorhombic structure of the LFO with no secondary phases.

As for other enzymes, ethylenediaminetetraacetic acid (EDTA) could forms complex compounds with metal elements on NR, thus made the structure of NR nonreversibly damaged and its activity lost.
Denny, Synthesis and Structure-Activity Relationships for 2,4-Dinitrobenzamide-5-mustards as Prodrugs for the Escherichia coli nfsB Nitroreductase in Gene Therapy, J.
Rodgers, Structures of nitroreductase in three states, J.
Tang, An improved structure model to explain variations of electric properties of polyaniline film in the reduction process by using double potential step technique, Electrochim.
Miller, Statistics for analytical chemistry, Ellis Horwood Limited, Chichester, 1988.

While ab initio calculations do not show the striking accuracy of experimental spectroscopy, still they could predict trends and provide useful information about the relative concentration of defects, their electronic structure, symmetry, spin state and even excitation energies.
Schematic diagrams of the electronic structure in the band gap are also depicted.
We applied two strategies in order to avoid this problem: i) once we obtained a reliable geometry from PBE calculation, we re-calculated the electronic structure by a screened hybrid density functional (HSE06) which was very successful in the quantitative description of native defects in SiC [11].
This functional contains a Fock-exchange term, which tends to localize the defect states and could provide, at least, qualitatively correct electronic structure of transition metal impurities.
A schematic diagram about the relative stabilities and defect structures is shown in Fig. 1.

More recent years, some chemists have adopted chemistry method to attach short chains and graft polymer onto CNTs [8,9].
CNTs are long, slender fullerenes where the walls of the tubes are hexagonal carbon (graphite structure) and often capped at each end.
The solubilization of CNTs via linking PSt might contain extended π-electronic structures that are isolated as a result of nanotubes surface modification.
It might be proposed that CNTs had been broken at their curved points and ends in the process of the reaction, because at these points, the structures consist of carbon atom pentagons which are not as stable as hexagon structure of carbon atoms.
The physical structure of the PSt-CNT copolymer may be described as follows: the axis is hard CNTs, and it strings the nanometer tiny balls of PSt together, which may be relatively soft but very elastic.

The inherent defect structure of LHA arises because its molecular stoichiometry, LaAl11O18, is incompatible with the stoichiometries of its putative parent structures, MAl11O17 (β–alumina) and MAl12O19 (magnetoplumbite).
The structures of both of these compounds consist of spinel–like blocks [Al11O16]+ separated by mirror planes containing the large cations [M+O]- and [M2+AlO3]-, respectively, in which the stabilizing cations (M+ or M2+) reside [8].
Willert-Porada [12] and Booske et al. [13] also propose that any abrupt nonuniformity in medium transport properties, such as free surfaces (space charge), grain boundaries, or amorphous–crystalline structure interfaces could provide an additional driving force for ionic diffusing and sintering in the presence of a microwave field.
Willert-Porada indicates that the magnitude of this effect not only depends on the structure and properties of materials but also depends on particle size and defect chemistry (i.e., smaller particle sizes increase the effect) [12].

Oil-chemistry Co. of China, Langfang, China abianhuan66252@126.com, bwangyuduo@bistu.edu.cn, c cya9@163.com Keywords: Micro-seismic signals, Wireless Data Acquisition, MG323, CC2530.
Geological features and geological structure of the relevant regional can be observed through the amplitude and frequency of the seismic waves.
Zigbee provides three kinds of network topology: star structure, tree structure and mesh structure.
Point-to-point network structure is complicated and suitable for distributed applications, such as military and Industrial inspection, etc.

The effect of the lattice distortion on physical, chemistry, mechanical properties and diffusion of the element may form nanometer phase or amorphous phase in the alloy at room temperature.
As-cast FeCoNiCrAl0.1 high entropy alloy has a FCC structure [8].
It is obtained from Fig. 2 that the phase structure of the alloy is FCC.
Therefore, the microstructure of the recrystallized FeCoNiCrAl0.1 alloy is a single phase with FCC structure.
FeCoNiCrAl0.1alloy with FCC structure has many movable slip systems, and orientation of the dislocation movement in the space is more diversified when the alloy is deformed under external force.

AA359.0 has a typical dendritic structure and many blow holes due to the sand casting process.
An important point is that in the case of cast alloy blow holes and coarse dendritic structures exist which act as sharp notches where cracks start preferentially.
The left one shows a fracture surface with dendritic structure of the cast alloy.
Fig. 10: Fatigue fracture surface with dendritic structure of cast alloy (left; experiment with turned specimen in salt solution, sa = 180 MPa) and of wrought alloy (right; experiment with shot peened specimen in salt spray fog, sa = 80 MPa).
Landolt; Corrosion and Surface Chemistry of Metals; 1.

The main chemical component of hemicellulose is pentosan, because some hemicellulose in the wood has much branched chain, low polymerization degree and amorphous structure, therefore, it is easy to hydrolysis and transform into oligosaccharide.
Because of the structure of hemicellulose was different, the relative rate of hydrolysiswas also have very great different.
Wood itself contained aldehyde, ketone and carboxyl, and the end glycosyl of polysaccharide contained acetal structure.
Meanwhile, a little pentosan occurred hydrolysis to produced end carbonyl which contained acetal structure, ( pentosed is likely to compose furfural by ehydrate reaction) leading to wood fiber almost no characteristic absorption in the position of C4, and the characteristic absorption was reinforced in the position of C3.
Wood chemistry [M].