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Investigated in detail that the kind of oxidants, concentrated acid ratio, oxidation time affected on the graphite expansion rate.
Because of the SG (new terminology called graphene) appeared just four years history (in 2004, Science for the first time to report the method using mechanical etching to prepare the SG [5].
Then, the researchers adopted different approaches to prepare SG, which has demonstrated an unparalleled physical properties (strange quantum Hall effect, good electrical and thermal conductivity and mechanical properties) and chemical properties, and has potential applications in engineering applications [6-9].
More importantly, the SG has a very large form-factor ratio (the surface density of SG is 2630 m2 g-1) [7], this is undoubtedly a huge gospel for the preparation of lightweight composite materials.
Table 2 The relationship of oxidation time and expansion volume of graphite treated by the different kind of oxidants oxidation time (min) 30 60 90 120 150 expansion volume KMnO4(0.2g) 441 393 385 351 347 K2Cr2O7 (0.1g) 380 400 365 343 332 Fig. 2 The relationship of oxidation time and expansion volume of graphite treated by the different kind of oxidants Fig.1 The relationship of oxidation time and expansion volume of graphite treated by H2SO4 and HNO3 at different volume ratio Choice of oxidation time.From Figure 2 we also saw that the oxidation time affected on the expansion volume.

Among its most important properties we can highlight the following: it acts as a barrier for gases, such as CO2, humidity and O2.
However, today this material seriously affects the environment worldwide, not only on land, but also in all ocean areas, significantly compromising the marine flora and fauna Analysis and Method The present research is of a descriptive type; it aims to describe in detail the characteristics, pros and cons of the different properties that PET bricks have in traditional bricks.
Physical and Mechanical Properties The physical and mechanical properties of the construction elements developed were established by means of laboratory tests
This optimizes the time, which leads to a lower cost and development in construction factor
Mechanical & physical properties of solid, masonry ceramic bricks

Synthesis and Characterization of Pb(Zr0.52Ti0.48)O3 Properties via High Planetary Mill N.
Grain size properties of Pb(Zr0.52Ti0.48)O3 ceramics increased with increasing the sintering temperature and duration.
However, the properties of piezoelectric ceramic are strongly influenced by their manufacturing procedures.
During firing process, the material is soaked for few hours to get the desirable properties.
This can be concluded that factors influencing the quality of sintered ceramics include of sintering temperature and duration of the sintering process [9].

Coupled electromagnetic and thermal analyses are carried out at each time step of simulation for correction of temperature dependent material properties.
Due to high cooling rates during the welding process, a different metallurgical structure and different mechanical properties compared to the base material occur in the seam and in the heat affected zone.
All of these influence factors and physical correlations have to be taken into account for the design and optimization of the HF induction tube welding process.
Thermal analysis with temperature dependent properties of steel includes also simulation of thermal losses by convection and radiation from all open surfaces of the calculated system.
They are based on coupled electromagnetic and thermal analyses with temperature dependent electro- and thermo-physical material properties.

The interest of the study on the implementation of expanded agglomerated cork as exterior wall covering derives from two critical factors in a perspective of sustainable development: the use of a product consisting of a renewable natural material – cork – and the concern to contribute to greater sustainability in construction.
Since this application is relatively recent, only about ten years old, there is still much to learn about the reliability of its long-term properties.
Figure 4 – New stains four months after the application of the boards Laboratory testing program Properties and performance aspects studied.
The presence of water in ICB-HD affects its thermal insulation effectiveness.
In another test was determined the reduction of the properties of water vapour transmission due to the application of a layer of polyurethane adhesive on the inner face (favourable location) of the boards.

They are known as conducting polymers and possess the electronic, electrical and optical properties of a metal while retaining the processability and mechanical properties usually associated with a conventional polymer [9].
The present work aims to evaluate the influence of different synthesis conditions of PANI doped with HF in its electrical properties when subjected to the presence of ammonia gas.
It’s also observed a positive synergy among factors 1,3 and 4 .
Table 2 - Test effects among electrical conductivity and other factors discussed in the experimental planning.
Table 3 - Correlation velocity of response test to ammonia gas with other factors.

KCl drilling study Wellbore instability is due to mechanical and chemical factors that caused two aspects.
The ultimate expression of the mechanical imbalance.
Wellbore instability problem solving, first through the brittle shale mineral composition and physical and chemical properties analysis, understanding the main factors causing wellbore instability, whereby technical ideas and research design sloughing of the pages of brittle knowledge base on the rock collapse mechanism, preferably a sloughing treatment agent, so the composition of a proper anti-sloughing drilling fluid system.
Different amounts of KCl plus segment selector and economic evaluation wells From a technical point of view, KCl content is higher, more stable drilling fluid properties, wellbore is also more stable, KCl content is higher, drilling fluid properties to resolve conflicts between stability and wellbore stability more thoroughly, but also the more meet the needs of mine.
Affects the formation of oil and gas in this system is small, and therefore may not be considering.

Introduction Toughness is a very important factor for materials design and application.
High impact toughness in base metal and heat affected zone (HAZ) is required for high strength pipeline steels [1-2].
Fig. 2 Optical micrographs in the specimens at the center (a, c) and surface (b, d) of steel plates 80µm a b c d 80µm 200µm 200µm Mechanical Properties and Microstructure Refinement.
Table 2 shows the mechanical properties of a 60mm thick steel plate.
Table 2 Mechanical properties of the steel plate σs, MPa σb, MPa σs/σb Elongation, % Akv, J (−40°C) Average 468 591 0.79 26.3 280 Range 420-500 560-625 0.71-0.85 24-32 194-293 Table 3 Notch impact toughness (Akv, J (−40°C)) through plate thickness Surface(up) 286 281 280 1/4 thickness(up) 291 283 285 1/2 thickness (middle) 294 293 287 1/4 thickness(bottom) 283 284 283 Surface(bottom) 295 294 288 Summary A ultra low carbon acicular ferrite steel was produced in a industrial scale at Xiangtan Steel with good combination of high strength and toughness by means of a special design of chemical composition, a special process of TMCP-RPC, in which the methods of grain refinement, precipitation strengthening, dislocation strengthening and structure strengthening were utilized to strengthen and tough the steel grade.

School of Mechanical and Automotive Engineering, Nanyang Institute of Technology 473004, china 3.
Introduction As a big agricultural country, China has abundant crop straw resources [1,2], According to Bi Yuyun and Cui Ming’s research, the amount of straw resources in more than 400 million t , straw biomass briquette is the main source of raw materials.Because different kinds of straw materials with the different physical and chemical properties , to change the main raw material for the forming and shaping of solid fuel combustion performance, other required materials are often mixed[3].
Combustion characteristics of mixed materials combustion characteristics of each material is linear or non-linear combination of the type and proportion of mixed material selection, and its burning characteristics will been affected.
Mixed with peanut shells or small wheat straw mixed materials in its activation energy in the combustion of volatile phases relative to the combustion of pure corn stalks, and its activation energy are reduced, but also shows that the pre-exponential factor reduces the intensity of combustion also reduces .
Add a small straw combustion characteristics of mixed materials and kinetic parameters less affected by wheat straw.

It should be noted that despite of the vast evidence of experimental data it is still not clear whether the observed differences are associated more with kinetic or more with mechanistic effects, i.e. it needs to be verified whether the rate of the processes or their mechanisms are affected by the material, oxidation conditions and/or other factors.
Statement of the Problem and Description of the Approach Description of alumina formers oxidation should involve several factors which may affect this process as well as refer them to the degradation process.
Mechanical effects are related to the stress generation and relief in the scale-substrate system as well as to interfacial phenomena.
It follows from it that there are other factors but composition which affect the oxidation resistance.
The mentioned response to stresses depends significantly on the material properties in terms of its deformation propensity and interfacial strength.