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The EBSD Investigation on Microstructure Evolution in Fe-32%Ni Alloy During Multi-axial Forging Baojun Han School of Chemistry and Life Science, GanNan Normal University, Ganzhou 341000, P.R.China hanbaojun80@tom.com Keywords: Grain refinement, Electron backscattered diffraction (EBSD), Fe-32%Ni alloy Abstract.
The disadvantages of TEM are that only small areas of a sample can be studied and complete characterization of dislocation cell and subgrain structure is very time-consuming because that reliable and automated analysis of Kikuchi diffraction is not yet available now [8].
Large amounts of grains orientation transition zone indicated by the color transition could be found in these banded structures.
The understanding of the formation of ultra-fine grain structure is of practical importance for controlling the properties of processed metals.
In the present investigation, it is concluded that the fine grained structures are formed by continuous process, i.e. grain subdivision or grain fragmentation, and the multi-axial forging deformation promotes the development of deformation bands in various direction followed by their frequent intersection in grain interiors because of changing of deformation axis from pass to pass.

The crystal structure as well as the phase purity of samples was identified by recording X-ray diffraction (XRD) patterns using Rigaku Ultima IV diffractometer with Cu Kα radiation (λ = 0.154 nm) operating at 35kV and 15 mA.
(a) shows the XRD pattern of the Sr1.78B2O5:0.11Eu3+, 0.11Na+ sample and the Inorganic Crystal Structure Database (ICSD) standard pattern.
It can predict that the doped Eu3+ and Na+ didn’t cause any significant change in host structure and had been efficiently incorporated into the host lattice.
According to the ISCD, the crystal structure of Sr2B2O5 phase belongs to the monoclinic space group P21/c with cell parameters a=11.850, b=5.350, c=7.710, V=488.79 Å3.
Chen, Journal of Materials Chemistry, 21 (2011) 6869

Computational Study of the Decomposition of Cyclotetramethylenetetranitramine under Impact, Friction, and Electric Fields Hui Hu1, a*, Miaomiao Li2 and Baoshan Wang1 1College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, People's Republic of China 2Shanghai Aerospace Institute of Applied Chemical Engineering, Huzhou, People's Republic of China ah_hu@whu.edu.cn Keywords: First-principles, HMX, sensitivity, impact, friction, electric field Abstract: Organic CHNO-containing high energy density materials have been widely used for storing large amounts of the chemical energies which can be rapidly transformed into heat upon various external perturbations during detonation.
It exhibits a monoclinic structure with the P21/c symmetry and two HMX molecules per unitcell (6.7 × 11.4 × 8.9 Å3).
Fig. 1 Structures of (a) model HMX (010) surface and (b) model HMX (100) surface.
Fig. 2 Minimum energy paths for N−NO2 homolysis and the atomic structure of HMX molecule.
More interestingly, the packing structure of the β-HMX molecules starts to be alternated considerably as the electric fields increase.

Influenceoflayered materialson properties ofcement stabilized macadam QUANHONG MA1, a, MEIYAN QU1, b, XUESONG XU2, cand LELE HU2, d 1School of Chemistry and Chemical Engineering, Southeast University, Nanjing, China 2Nanjing Road and Bridge Engineering Company, Nanjing, China amqh@seu.edu.cn, bqmytt@126.com, cxxs721227@163.com, dnjlqhll@139.com Keywords:Layered materials; Cementstabilized macadam base; Palygorskite; Montmorillonite;Kaolin; Crack resistance;Strengthproperties AbstractTo reduce shrinkage cracks of cement stabilized macadam base and prolong the life span of pavement, layered materials were mixed in cement stabilized macadam to improve its strength properties and crack resistance.In comparison with the blank test, the unconfined compressive strength increases with the addition of layered materials (weighed at 10% of the amount of cement), by 11.6% with palygorskite, 12.7% with kaolin and 8.9% with montmorillonite, respecetively, at the curing age of 28 days; dry-shrinkage
These cracks destroy the integrity and continuity of pavement structures severely and negatively affect the overall quality and life span of the highway.
Experimental results and discussion Influence of layered materials on strength properties Cement stabilized macadam base is the main supporting layer of the pavement structure.
Table4Influence of layered materials on rigidity properties Layered materials Content of layered materirals [%] Compressiveresilient modulus [MPa] Splitting resilient modulus [MPa] Blank 0 1821 1215 P 10 1862 1040 K 10 1796 1197 M 10 1849 1009 The larger resilient modulus of the base leads to an overall greater stiffness of the pavement structure.
Furthermore,with the addition of palygorskite, a net-like structure is formed in cement pastes,leading to the maximum decrease in shrinkage cracks of cementstabilized macadam mixed with palygorskite.

In stereochemistry of SN1 reaction, seen from step I that tert-butyl bromine dissociates into tert-butyl carbocation, the carbon atom turns into sp3 hybridized carbocation with a plane triangular structure from sp3 hybridized tetrahedral structure and there is an empty P trajectory on the carbon atom with positive charge.
However, which mechanism it is based on is related to such factors as the structure of haloalkane, and properties of leaving group, nucleophilic reagent and solvent.
Influences of hydrocarbyl structure The type of halide is an important factor to make the reaction inclined to SN1 or SN2 mechanism.
Organic Chemistry [M]

However, the colloidal crystal films are difficult to use or integrate into photonic crystal circuits without a post-structuring process.
Even though large area opal films of single composition can be efficiently fabricated with vertical deposition method, more complex architectures are difficult to make without a previous lithographic structuring step [16].
The arrangement of the colloidal crystals into more complex structures using vertical deposition method without templates has not been reported up to now.
The diameters of the silica spheres were 200nm, 300 nm and 600nm (Technical Institute of Physics and Chemistry of Chinese Academy of Science) with a relative standard deviation of about 4%.
More colloidal particles from the bulk suspension are driven toward the meniscus by a convective transport to eventually self-assemble around the nucleus to form a crystalline structure caused.

Changes in chemical composition of materials occurring during fine grinding were observed and published first already in 1894. [5] and the term of "mechano-chemistry" in 1919 [6].
At present it is obvious the surface sizes, structures, activities and the internal chemical and crystal composition of materials can be modified by a controlled mechanical activation process [16-23] Materials and experimental procedures Nowadays, ceramic items are normally produced with materials having submicron and nanoparticles [24-28].
Some of the most important from them are the followings: • Chemical and mineralogical composition of ground material; • Crystal structure and lattice parameter of mineral components; • Volumes and values of stresses developed in material particles during grinding; • Interatomic bonding forces on surfaces and inside of ground particles; • Grinding times and temperatures.
• Using controlled mechanical activation not only the surface sizes, structures and activity, but the internal chemical and mineral structures and compositions can be modified at brick clays with complex mineralogical composition, like Lenti clay.

Introduction Foam glass is an insulation material, which is gaining its popularity for the insulation of unique buildings and structures.
Installation of foam glass thermal insulation in such unique objects as the Grand Kremlin Palace (the roof of the Winter Garden — insulation of the basement walls), the building of the Accounts Chamber of the Russian Federation (insulation of the roof), sports complex and the Olympic swimming pool (insulation of the roof) and many other unique buildings and structures, both in Russia and Europe is the confirmation to the fact.
This makes the use of foam glass for the construction of the most complex structures, including fire retardant ones, possible.
Nikishov, Kinetics of Cellular Structure Formation at Thermal Treatment Processes Simulation in the Cellular Glass Technology, Materials Science Forum Submitted. 931 (2018) 628-633
Chemistry and Chemical Technology. 57(3) (2014) 73-79.

In RE-aluminizing, because chemistry activity and atom radius of RE are all big, the surface for treated steels well produces a large number of vacancies and forms concentration gradient of vacancies after RE permeating into steel, at the same time, vacancies well happen migration and diffuse to inside together with solute atoms.
Yu and Chen [9] considered that the solute-vacancy complex is made up of a substitution solute atom and a vacancy by analyzing the structure and diffusion method of the complex.
Suppose the interaction energy of atom-pair is , the interaction energy of atom-vacancy pair is , and the coordination number of the crystal structures is , then, the formation energy of a vacancy can be written as:
(6) Because the crystal structure of aluminum is face-centered cubit structure and its sublimation heat is 6.83eV, the binding energy between aluminum atom and vacancy is: .

These types do not attack concrete structures, mainly because they are associated with the environment outside the use of this building material [8, 10, 11].
Possible cyclic chemical reaction between SRB and SOB [11] With regard to acid corrosion of concrete (type II corrosion), it is necessary to take into account the activity of nitrifying bacteria, which under suitable conditions can generate biogenic nitric acid (HNO3) and in this way disrupt the integrity of concrete structures.
In particular, some representatives of micromycetes, ie eukaryotic fibrous microscopic fungi, are able to penetrate their mycelium into its capillary pore structure and disrupt it.
Bryophytes damages concrete mainly mechanically by the penetration of rhizoids into its porous structure.
[9] KURDOWSKI, W., Cement and Concrete Chemistry, Springer, ISBN: 978-94-007-7944-0, 2013