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Box 135, Pohang 790-600, Republic of Korea 2 Center for Advanced Aerospace Materials, Pohang University of Science and Technology San 31 Hyoja-Dong, Pohang 790-784, Republic of Korea 3 Department of industrial chemistry, PuKyong National University 599-1 Daeyeon 3-Dong Nam-Ku, Pusan 608-739, Republic of Korea Keywords: Synchrotron X-ray absorption spectroscopy, Organic coating, Corrosion evaluation Abstract.
Introduction Organic paint coatings are widely used to control corrosion of steel structures, both to maintain an appearance and to prevent the loss of a structural integrity.
The anti-corrosive organic coatings cover about 50 % among corrosion protections of the steel structures [1].
Since the undercoating corrosion can lead to a failure of the steel structures if not detected at an early stage, the detection of corrosion under the organic coatings at the earliest stage is an important issue toward improving a safety and reducing a cost.
Whilst a considerable progress has recently been made in the theoretical treatment of XANES (X-ray Absorption Near-Edge Structure) spectra [15], qualitative treatment, relying on comparing the data from experiments with those obtained from appropriate reference compounds, remains by far the most widely used approach.

Due to the weak forces between of layers and some charge deficiencies in the structure, water molecules can be easy intercalated into the interlamellar space of bentonite, leading to an expansion of the minerals.
X photoelectron spectra (XPS, Escalab210, Vg Scientific Ltd., UK) analyses were utilized for surface chemistry determination.
Scan electron microscope (SEM, JSM-6701F, Japan Electron Optics Laboratory Co., Ltd., Japan), Powder X-ray diffraction (XRD, XRD-6000, Shimadzu Emit Co., Ltd., Japan) were utilized for structure and crystal analysis.
It can be found that the natural bentonite exhibit typical layer structure.
The prepared composite still retain the layer structure of bentonite, but abounding carbom nanoparticles distribute on the surface of the prepared composite.

The composites are multi-laminated with altering structure when they flow between two laminating parts, some melt spreads along vertical direction from horizontal direction, so is the other melt.
The CB dispersed in the PP matix with chain or grape structure when PPCB was conductive.
As the number of laminating elements increased, the composites bore more and more shearing and blending action, so partial structure of CB may be destroyed and the conductive effect weakened.
Journal of Polymer Science: Polymer Chemistry Edition, 1979, 17: 2163-2172
[6] Chad D., Hiltner A., Becr E., Novel structures by microlayer coextrusion-talc-filled PP, PC/SAN, and HDPE/LLDPE.J.

Introduction Molecular assembly technology has attracted much research attention due to its flexible applications in modulation of surface property and construction of advanced materials and nano-structures and even devices over the past decade [1-3].
Even more, tunable optic properties have been achieved in a highly predictive manner for metal-coated core-shell structures by varying the metallic shell thickness and core size[14].
However, problem remains in solution chemistry.
As to the traditional electroless plating technique, though it is a promising method for forming uniform metal coating on any kind of activated substrates regardless of the shape, size and conductivity in principle, it is difficult to obtain objective products of uniform shell coated core structures, without free metallic species or core template.
By comparing Fig.2(a) with Fig2(b), we could see that there are diffraction peaks of fcc-structured crystalline copper in addition to that of ceramic particles in Fig.2 (b).

A network structure was formed by hydrogen-bonding pattern with a large numbers of hydrogen and nitrogen atoms of the guanidine group.
Structure and proton labeling of guanidinylated chitosan (GCS) Figure2.
FT-IR spectra of GCS and CS Figure3. 1H NMR spectra of GCS and CS in DCl/D2O and D2O at 298K The chemical structures of GCS and CS were studied by assay of the 1H NMR spectra, and the results were shown in Figure3.
The structure of GCS was confirmed by FT-IR and 1H NMR spectra.
Qian: Current Medicinal Chemistry, Vol. 20(2013), P. 79-94 [2] S.

The geometries, electronic structures, and electronic absorption spectra of these dyes are studied by DFT and TD-DFT.
Because the D-π-A structure of TPAR may be easy to form the formation of dye aggregation on the semiconductor surface and the recombination of conduction band electrons with triiodide in the electrolyte.
The geometries, electronic structures, and electronic absorption spectra of these dyes are studied by using density functional theory (DFT) and time-dependent density functional theory (TD-DFT).
Fig. 3 Molecular orbital spatial distribution of TPRA, D1, D2 and D3 The electronic structures of HOMO-1, HOMO and LUMO of the four dyes are shown in Fig. 3.
Summary In the paper, the geometries, electronic structures and UV-vis spectra of TPAR, D1, D2 and D3 are studied by DFT and TD-DFT methods.

Exposure to temperature of 800 °C, the geopolymer lost its strength due to extremely densification and expansion processes of the high unreacted silicate phase in the structure.
Additionally, as the geopolymer exposed to 800 °C, the structure did not return any residual strength as it underwent extremely densification and expansion processes with severe cracking and dimensions changes.
The water in the geopolymer structure transformed to a water vapor when the geopolymer heated further than 100 °C [7] and its pressure increased continuously with increasing the heating temperature.
Figure 1b presents the SEM micrograph of the geopolymer paste exposed to 400 °C, shows the developing in the micro-crakes growing due to the high water evaporation rate from the dense structure.
Davidovits, Chemistry of geopolymeric systems, terminology in: proceeding of International Conference on geopolymers, Geopolymer ’99 International conference, Geopolymer Institute, France. 32: 9–40 (1999)

It was found, studying acrylonitrile copolymerization with ethyl acrylate in dimethyl sulfoxide under the action of anionic initiating system of 1,4-diazabicyclo[2.2.2]octane – ethylene oxide, that the obtained copolymers have a branched structure.
Thermal behavior of copolymer samples was investigated; it was found that ethyl acrylate, being introduced into the polyacrylonitrile structure, both reduces thermal effects related to the reactions taking place during heat treatment of copolymers, and increases the half-width of the heat release peak.
We evaluated the EA presence effect on the structure and properties of synthesized copolymers in this work (Table 1).
Kozlov, Properties and structure of polyacrylonitrile fibers, Polymer Science Series A, 52 (2010) 1233–1238
Badamshina, Anionic Copolymerization of Acrylonitrile with Methyl Acrylate under the Action of a Novel Initiating System Based on a Bicyclic Tertiary Amine and Ethylene Oxide, Russian Journal of Applied Chemistry, 93 (2020) 1009–1018

Concrete can be found in almost every building structure, be it a pavement, a bridge, a house, a tunnel or a dam.
As defined by the Italian technical standards for construction reference DM 14.01.2008 [17], concrete and/or structure durability is defined by the retention of its physical and mechanical properties which are essentials to maintain the lifespan safety of the structure.
The European concrete standard EN 206-1 defines different risks that can occur to a concrete structure [21]: ü It applies to the concrete cast in situ or precast structures and structural precast products for buildings and civil engineering structures.
The mix design of concrete structure has a direct sustainable impact on its durability and performance.
Crow, The Concrete Conundrum, Chemistry World, March, 2008, pp. 62-66

The mesoporosity structure and inner hollow cavities of Pd/CNTs catalyst are responsible for the distinguished properties.
The excellent activity of Pt/CNTs catalyst is mainly related to the particular pore structure, which accelerate the diffusion rate of reactants and products.
The mesoporosity structure of CNTs is desirable for cyclohexanone desorption, which prevents cyclohexanone transferring into cyclohexanol.
In conclusion, the combination of mesoporosity structure and inner hollow cavities of Pd/CNT catalyst are responsible for the distinguished catalytic behavior.
Arpe, in: Industrial Organic Chemistry, 2nd edn., VHC, Weinheim, 1993, 251