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This paper describes a proper low cost way to fabricate defect-free porous carbon preforms with interconnect pore structure for making reaction formed SiC (RFSC).
This paper focus on fabricating defects free porous carbon preforms with interconnected fine pore structure for RFSC at low fabricating cost, taking room temperature freezing casting and carbonizing process, after Si infiltrating, the RFSCs was finally fabricated.
The pore structure was characterized by mercury intrusion porosimetry (PoreMaster60, Quantachrome, USA), and the microstructure of them was observed by SEM (model: JSM-5800, Jeol, Japan).
From Fig.2, we know there are two kinds of pore structures in the porous carbon preform: the larger dendrite pores and the smaller irregular pores.
Materials Chemistry and Physics, 2014, 143 (2) : 707-712

It was postulated that the presence of MMT layered structure introduced a more tortous path for the diffusing of oxidant molecules, thereby decreasing their permeability towards mLLDPE molecular chains.
They found that the nanocomposite incorporating the most hydrophobic organoclay resulted in greater biostability by hindering greater extent of matrix surface re-structuring upon oxidative exposure [5].
In an effort to develop new class of biomedical materials, we insist in studying the structure and properties of the mLLDPE nanocomposite incorporating montmorillonite (MMT) nanoclay, in order to assess its suitability for use in a broad range of biomedical devices.
This suggests that the presence of MMT layered structure may introduce a more tortous path for the diffusing of oxidant molecules, thereby decreasing their permeability into the mLLDPE molecular chains.
Thus, these findings may merit further investigation on structure-property relationships and long-term in vitro mechanical properties and stability under varied environmental ageing for complete investigation on the biostability of this nanocomposite system.

Then, on the basis of the quasi-circle characteristic of the target image, we proceed to maximize the erosion with circular structure in order to prevent under-segmentation.
Assuming that X stands for the target image and B for the structural element, the mathematical expression of the target image X corroded by the structure element B is defined as follows
The basic idea is viewing an image as a topology structure diagram, where gray values are considered as height values of topography.
In consideration of the quasi-circle feature of the bars’ end face images, circular structure elements have been chosen to do the morphological operation
Computers and Applied Chemistry. 27 (1):99-102.

Gold catalysts supported on the macroporous nanoparticles composited of cerium oxide for oxidation of formaldehyde Changyan Li 1,2 a, Songsong Chen 1, Zhixue Zhang 1and Jun Zhang 1,2a＊ 1College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohht 010021, P R China 2College of Life Sciences, Inner Mongolia University, Hohht 010021, P R China ali.changyan00@163.com a＊Corresponding author email: cejzhang@imu.edu.cn Keywords: Gold catalyst, Macroporous CeO2, Mesoporous SBA-CeO2, Formaldehyde catalytic oxidation Abstract: A series of Au/CeO2 catalysts were synthesized and evaluated for formaldehyde catalytic combustion oxidation.
In Au/CeO2 catalysts, CeO2 supports with different structure,Au/Macroporous-CeO2 is found to be superior catalyst for formaldehyde catalytic oxidation.
The phase structure, geometry and pore size were determined by XRD, TEM.
Transmission electron microscopy (TEM) characterization was performed on a JEM-2010 system, operating at an acceleration voltage of 120 kV to evaluate the structure, geometry and pore size in the catalyst.
The XRD patterns clearly illustrate the phase structures of catalysts can be indexed to cubic phased CeO2 (JCPDS: 34-394), as characteristic diffraction peaks with 2θ at 28.50, 33.08,47.49, 56.34, and 76.70 correspond to (111), (200), (220),(311) and (331) lattices of cubic structured CeO2, respectively.

After magnesium oxide is made in the nanometer scale, due to the dramatically increased specific surface area, higher surface energy, it has high surface activity, strong adsorption, and good low-temperature sintering performance and so on, leading to its special properties on the aspect such as force, heat, light, electricity, chemistry, biology and so on[5-6].
The characterization of the structure and properties of this powder was conducted by means of TG, XRD, SEM and FT - IR methods.
The results showed that the characteristic diffraction peaks of MgO structure were all presented in the XRD spectrum of MgO (where the 2θ were 36.7°, 42.8°, 62.2°and so on), which was consistent with the MgO standard card（Card Number:04-0829).
With the existing of high concentration and strong oxidizing oxygen ions, bacterial cell membrane structure was easily damaged and bacteria were killed quickly[9].
Because of the strong adhesion, cell structure of bacteria was easily damaged.

Scaffold in bone tissue engineering must have a three-dimensional (3-D) interconnected porous structure acting as a template for bone tissue regeneration, and material fabricating the scaffold must be biocompatible and can provide structural support during bone growth and remodeling at the same time.
To serve as a scaffold, it must have a three-dimensional (3-D) interconnected porous structure, which is of benefit to cell attachment, proliferation and differentiation, and provide pathway for body fluids.
Addition of polymer could enhance the toughness of HA and mimetic the inorganic/organic components and structure of natural bone.
PA6 has a molecular structure similar to bone collagen, while nano-hydroxyapatite (n-HA) has high surface activity and its size and component similar to the mineral found in human hard tissues. n-HA/PA6 composite has good mechanical and biological properties [4] .
The possible reason is due to the stability of tetrahedron structure of PO43- .

Ma1, c 1 SHU-SOEN’s R&D Lab, Department of Physics, Shanghai University, Shanghai 200444, China 2 Department of Chemistry, Shanghai University, Shanghai 200444, China a wgzhao@shu.edu.cn, b qin_zhang@staff.shu.edu.cn, c zqma@staff.shu.edu.cn Keywords: ZnO nanowires; seed layer; oxygen vacancy; chemical stoichiometry Abstract.
The physical phase and morphology of the ZnO thin films with nanowires structure were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively.
However, the present obstacle is how to fabricate the films with micro- and nano- structures on the topmost surface.
The XRD pattern also indicates a wurtzite structure with a high crystallinity.
ZnO is a wurtzite crystal structure with a hexagonal form illustrated in Fig.2c, and its preferred growth direction is mostly along the C axis.

Titania (TiO2) is one of the most unique catalysts, crucially important in photo-green chemistry.
Nakashima, Synthesis of silica hollow nanoparticles templated by polymeric micelle with core−shell−corona structure, J.

The porous carbons prepared with chemical activation possess highly porous structure.
Results and Discuss The structure of the products was examined by X-ray diffraction (XRD).
However, the graphite structure of the porous carbons gradually decreases due to the intercalation of MnO2 into carbon lattices leading to the collapse of graphite structure.
This porous structure combined micropores and mesopores is positive for the supercapacitors.
Frackowiak, Physical Chemistry Chemical Physics, Vol. 9 (2007), p.1774

Perkins, Concrete Structures: Repair, Waterproofing and Protection, Applied science publication, LTP, London,1976
Breck, Zeolite Molecular Sieves: Structure, Chemistry and Use, John Wiley and Sons Inc., New York,1973
Gerasimenko, Protection Against Corrosion, Aging and Biodegradation of Machinery, Equipment and Structure, Vol. 1, Engineering Publish, Moscow, 1987
Collection of scientific publications “Building Structures”, DPNDIBK, Kyiv:,(73)2010, pp.566-574
Kirichok, Rehabilitation of concrete surfaces of hydropower engineering structures deteriorated by soft corrosion and cavitation, J.