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As for SiC materials, its failure reason mainly reflected in: (1) The oxidation of SiC generated direction stress and it could cause volume effect on the condition of temperature changed sharply, all these would lead to the sagger structure loose step by step until failure in the end
(2) The sagger isn’t densification or its consistency uneven which leading to loosen of its structure and dropping of the heating resistance.
In Chinese [5] Chunxia Chen, Structure and Properties of Al2O3-Si3N4-SiC composite materials used in blast furnace [D], University of Science and Technology Beijing, 21~34, 2010.
In Chinese [9] Wenchao Li, Theoretical basis of new type refractory –Physical chemistry design for ceramic composite in modern times [M], Deology publishers, 7~8,2001.

Physio-Chemical and Thermal Characterization of Sorghum Bagasse Fiber for Sustainable Composite Application Rachael Ayanbukola Otunla1,a*, Adekunle Akanni Adeleke2,b, Temitayo Samson Ogedengbe2,c, Seun Jesuloluwa2,d, Rasheed Enechojo Abuh3,e and Waliyi Adeleke2,f 1Department of Industrial Chemistry, Nile University of Nigeria, Abuja, FCT, Nigeria 2Department of Mechanical Engineering, Nile University of Nigeria, Abuja, FCT, Nigeria 3Department of Mechanical Engineering, Waste to Wealth, Nile University of Nigeria, FCT, Nigeria a*20222433@nileuniversity.edu.ng, badekunle.adeleke@nileuniversity.edu.ng, ctemitayo.ogedengbe@nileuniversity.edu.ng, dseun.Jesuloluwa@nileuniversity.edu.ng, eabuhrasheed@gmail.com, fadeleke.w.a@nileuniversity.edu.ng Keywords: natural fiber, bagasse fiber, sustainable composites, POP.
However, in its more common dihydrate form (CaSO₄·2H₂O), where water molecules are integrated into its crystal structure, it typically consists of around 23.3% calcium and 18.5% Sulphur.
Lignin degrades over a broader range (250–500+ °C) due to its aromatic, cross-linked polymer structure [11].
Major lignocellulosic functional groups (O–H, C–H, and C–O) were confirmed by the FTIR spectroscopy, indicating a cellulose-rich structure conducive to fiber-matrix adhesion.

Ferrous-ferric oxide (Fe3O4) has a cubic inverse spinel structure which consists of a cubic closely packed array of oxide ions where all of the Fe2+ ions occupy half of the octahedral sites and the Fe3+ are split evenly across the remaining octahedral sites and the tetrahedral sites [8].
The XRD profiles of both samples show typical diffraction peaks of Fe3O4 [JCPDS NO.65-3107] crystalline structure.
The results indicate that there is no change either in composition or structure Fe3O4 particles when coated with carbon film.
Power Sources, 30, (2000) p. 1133-1136 [8] Information on http://www.mahalo.com/iron-ii-iii-oxide [9] Greenwood, Norman N and A.Earnshaw, (1997), Chemistry of the Elements (2nd ed.), Oxford: Butterworth-Heinemann, ISBN 0-7506-3365-4 [10] V Yeager, A K Lin and H.Dao: J New Mater.

The sample consisted mainly of crystalline aragonite phase with an orthorhombic structure (JCPDS 41-1475).
There existed a little amount of calcite with a hexagonal structure (JCPDS 05-0586).
XRD patterns of samples prepared using Na2CO3 without an basic additive or using NaOH at 180 oC (Figs. 1c and e) indicate a mixture of thermodynamically stable calcite with a hexagonal structure (JCPDS 05-0586) (main phase) and aragonite (minor phase).
Talham: Biomineralization: Principles and Concepts in Bioinorganic Materials Chemistry Stephen Mann (Oxford University Press, New York 2001)

In the conventional method of W-Cu composites fabrication which includes infiltration of molten copper into tungsten skeleton, the composite suffers from low density and inhomogeneous structure of the product [9].
As seen, the agglomerated structure of the powder is kept which can be attributed to the CVT mechanism of powder reduction [18].
It is worth mentioning that the availability of liquid copper throughout the solid structure of tungsten particles promotes a more intensive particle rearrangement and hence, no serious W poor region can be found and interparticle spacings are negligible.
Logan, Physical chemistry for the biomedical sciences, Taylor and Francis Inc., CRC Press, 1998, p.143

Nano-Kaolin’s dispersibility: Nano-kaolin scattered to cement particles need to choose a good dispersion method to better improve the distributed quality and improve the mechanical properties of scattere system[2].Considering the nano kaolin in water have very good dispersion, water is the raw material to make cement colloid, and also in cement colloid and concrete preparation process use mechanical agitation,so this paper adopt a method combed physics and chemistry, is also a kind of simple easy to implement method: First, the nano-kaolin is scattered to the water, fully mixing make nano-kaolin dispersed in water even, and then in the cement colloid fabrication process, nano-kaolin is joined in cement with the water together, and extend the cement colloid mixing time, get a good dispersion effect, make the nano-kaolin maximum limit in cement fully scattered.
The analysis thinks kaolin nanoparticles can significantly increase cement water requirement, main reason is similar to SiO2, nano zirconium dioxide (ZrO2) and other nano materials and so on, as a result of this kind of nanometer material with large specific surface area and in cement paste may form clusters network structure.
These nanoscale subtle pore can use the nano kaolin grain to fill which have no enough time to participate in ash reaction , thus make cement stone density increase, micro structure improve, and increase its strength.Compared with ordinary ore, kaolin nanoparticles in the early filling effect is good[4].
Conclusion The overall water demand increases with nano kaolin replace rate, Nano kaolin can significantly increase cement water requirement, main reason is similar to nano SiO2, nano zirconium dioxide (ZrO2) nano materials, because this kind of nanometer material have large specific surface area and can form the floe group network structure in cement paste.

Preparation, characterization and tribological evaluation of calcium borate nanoparticles as lubricant additives Jiusheng Li1*, Lifeng Hao2, Xiaohong Xu1, Li Zhang1, Tianhui Ren2 1Petrochina Lanzhou Lubricating Oil R&D Institute, Lanzhou, 730060, China; 2School of Chemistry and Chemical Engineering, Shanghai Jiaotong University, Shanghai 200240, China * E-mail: lijiusheng_rhy@petrochina.com.cn Keywords: Nanoparticle, Calcium borate, Oil-solubility, tribological property Abstract.
This is because that its structure of borate is more complex than other salts, which causes the difficulty of surface modification of borate [12,13].
So these complicated relationships may be attributed to not only the presence of boron in molecule structure but also the dispersing methods to solve the oil-solubility of calcium borate nanoparticles.
Fig.7 Micrographs of worn surfaces lubricated by (a) base oil alone and (b) MCBN added-oil (0.75wt %) under 196 N (amplification factor ×100) XPS analysis of the worn surface is subjected to ascertain the chemical structure of tribofilm and infer the action mechanisms of calcium borate nanoparticles as an additive in the base oil.

The Ti-6Al-4V was surface treated by plasma electrolytic oxidation (PEO) technique for 12 min under optimized conditions of electrical processing parameters and electrolyte chemistry.
It can be seen from SEM surface micrographs, all the samples (LDLF, LDHF, HDLF and HDHF) exhibit a porous structure over their surfaces with circular and irregular dark spots which are discharge channels open to the surface of the coating.

The deposition process for CVD diamond film mainly depends on the combination of gas phase chemistry in the reactor and surface adsorption mechanism on the substrate, which can be regarded as the key to determine the film quality [4].
Much work has been carried out to study the gas phase chemistry in the CVD diamond film reactor [4-28].
Electronic structure theory has played an important role in the development of a molecular-level understanding of diamond CVD.

took into account the structure of water users and then built models to deal with economic policies and financial arrangements for sustainable watershed management [25] .
Physics and Chemistry of the Earth.
Physics and Chemistry of the Earth, Parts A/B/C.