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Aim of the work is to compare the morphological properties of TiO2 powders obtained by different methods.
Therefore, one of the main factors enhancing the detection properties of these oxides used for gas sensing is their grain size reduction [3].
The main advantage in using TiO2 as reducing gas sensor is that the response is much less affected by humidity than the response of other oxide as SnO2; this makes titania suitable for environmental monitoring.
The transformation from anatase to rutile occurs during heating or even mechanical grinding.
The present work compares the physico-chemical properties of titania nanoparticles syntesized by sol-gel and sol-gel-hydrothermal routes.

Castings can be affected by defects (presence of voids or cavities, inclusions and oxides).
Adopting the ceramic cores, enhanced mechanical properties, in terms of stiffness, bending and compression strength has been attained, which are able to withstand the stresses generated during the semi-solid casting process.
The attained, very promising properties favour their use on very high performance cars.
Ceramic cores can offer the desired mechanical properties for each specific application thanks to a tailored sintering process.
[9] Rosso M., Peter I., “New frontiers for thixoforming”, International Journal of Microstructure and Materials Properties, Vol. 8, Issue 1-2, 2013, pp. 113-124 [10] Zhen Z., Ma Qian, Ji S., Fan Z., “The effects of rheo-diecasting on the integrity and mechanical properties of Mg–6Al–1Zn” , Scripta Materialia 54 (2006), 207-211, ISSN 1359-6462

Modeling (1 I) • A plenary session convened the participants with seven Plenary Lectures (respectively on "The Future for High-Temperature Materials and Coatings in the New Millennium"; "Impurity Segregation to Scale/Alloy Interfaces and its Effect on lnterfacial Properties"; "High Temperature Oxidation Kinetics of Non-Oxide Monolithic and Particulate Composite Ceramics"; "Carbonlnduced Corrosion of Metals and Alloys"; " Interactions between oxidation and deformation at high temperature"; "Practical Aspects of the Reactive Element Effect"; and "Protection of Materials at High Temperature.
Modelisation. (11) Sept conferences plenieres ont ete presentees portant respectivement sur "The Future for HighTemperature Materials and Coatings in the New Millennium"; "lmpurity Segregation to Scale/Alloy Interfaces and its Effect on Interfacial Properties"; "High Temperature Oxidation Kinetics of NonOxide Monolithic and Particulate Composite Ceramics"; "Carbon-Induced Corrosion of Metals and Alloys"; "Interactions between oxidation and deformation at high temperature", "Practical Aspects of the Reactive Element Effect"; "Protection of materials at high temperature.
The Symposium was devoted to all aspects of high-temperature degradation of materials resulting from the main actions of hightemperature, chemical, and mechanical environments.
These were equally divided among the effects of mechanical constraints on oxidation, thermal cycling effects (especially stress measurement), and erosion behavior.
[n reviewing opinions among the participants of the technical content of the Symposium, there was some sentiment expressed that there were fewer sessions than at previous Symposia that featured intense examination of the mechanistic aspects of a given topic, such as occurred with, for instance, the factors affecting scale spallation in Syn1posium IV, and more papers that presented results that lacked significant mechanistic explanation.

To improve the performance and widen the practical application field, the mechanical properties of 3003 Al alloy have been widely studied in past decades [4-7].
Dynamic recrystallization (DRX) plays an important role in reducing the flow stress and the grain size as well as a powerful tool for controlling mechanical properties during 3003 Al foil is produced through hot rolling [8-11].
The aim of this investigation is to obtain 3003 Al alloy with different metallurgical quality by different melt-treatment methods, discuss the relationship between metallurgical quality and hot deformation activation energy (Q), and establish the mathematical model of DRX critical strain and the Zener-Hollomon parameter, which is beneficial to predict and achieve the desirable mechanical properties of the final product. 2.
Dislocation moving and acting reciprocally are essential for plastic deformation, which is remarkably affected by metallurgy defects of 3003 Al alloy.
It is the main factors that oxidation inclusion (Al3O2) in the 3003 Al alloy to block deformation.

At present, there exist some random factors both in design and construction stage and in service stage as far as whole life cycle is concerned, which contribute more to deviation between calculated value and practical value of effective prestress.
This may greatly affect the durability and life, and even lead to safety disaster [2,3].
However, limited by something such as properties of concrete and reinforcement, maintenance and humidity condition, craft for prestressing and so on, the NDT technique on prestressing strand is still start from scratch [4-6].
Fig.9 Large-scale beam model Fig.10 Distribution of Effective prestress for Z2 tendon Conclusions ●Because this technique rely on static balance equilibrium and synthesize many aspects’ influential factors including local deformation, analogy boundary condition, bending and tensile stiffness of stretching cable wire etc, it has the advantages of clear concept and strong adaptability.
Mechanical Systems and Signal Processing, Vol. 20 (2006) , p. 2186

In addition, the nuclear reaction process between the incident particles and materials can produce transmutation atoms and spallation products such as helium atoms in materials, which can affect the microstructural evaluation and mechanical properties of the material [13].
In the irradiation and annealing specimens, these mechanical properties and microstructures including positron annihilation analysis and kMC simulation were examined to understand the effects of helium production and displacement damage on mechanical properties and microstructures.
Takada, Effect of gas atoms and displacement damage on mechanical properties and microstructures of F82H, J.
Aoto, Irradiation effect on mechanical properties in structural materials of fast breeder reactor plant, J.
Takada, Effect of gas atoms and displacement damage on mechanical properties and microstructures of F82H, J.

It can be used to machine almost any hard, brittle and difficult-to-machine material, and is not restricted for conductive properties of materials.
Aimed at the disadvantages of above design and synthetically considered the two factors of cost and efficiency, this improvement has been done from the structure design of electrode and nozzle and the design of cycle cooling method, as shown in Fig. 8.
Only for machining techniques, the choice of machining parameters is profoundly influenced by many factors, such as different materials (ceramic, hard multiplex steel, etc.), different shapes (plane, abnormity surface, etc.), and different locations (center, margin, corner, etc.).
Furthermore, the mechanical properties of machined materials need be examined, the machining mechanism can't be understood completely and the accessories of the MDAM system need be also improved aftertime.
Zhang: China Mechanical Engineering, Vol. 20(2009): p. 2567-2570 [3] W.J.

There are four primary constituents in a thermal protection system, each of which has specific properties and functions (Fig.2).
Two factors affect the rumpling of the TGO: (a) local volume shrinkage induced by transformation of β-(Ni,Pt)Al to γ'-Ni3Al or γ-Ni; (b) the visco-plastic deformation of the bond coat in order to release the growth stress or thermal misfit stress during thermal cycling.
However, subsequent studies indicated that the oxide thickness (volume) is only one of the many factors (eg.
Cr 3+ concentration, stress state) affecting luminescence intensity.
Finally, there will be remain a strong need for characterisation of the mechanical properties such as interfacial toughness, stresses, and elastic modulus of TBC systems.

Introduction Copper in the simple and alloying cast iron improves the antifriction properties [1-6].
It was also assumed that one of the main factors that would significantly affect the distribution of copper formations in cast iron was the carbon equivalent, which governed the carbon or silicon ratio.
Crystallization kinetic factors play an important role that impacts on the possible sizes of the droplets as well as the final results of the system differentiation.
[4] Agunsoye, J.O., Bello, S.A., Hassan, S.B., Adeyemo, R.G. and Odii, J.M. (2014) The Effect of Copper Addition on the Mechanical and Wear Properties of Grey Cast Iron.
Graphitization and properties of cast iron.

Based on the nonlinear dynamical model of the gear system considering friction, the system periodic motion is studied by the Shooting algorithm, also the stability and bifurcation properties of the system periodic motion is obtained by Floquet multipliers.
The system's evolvement properties are presented under different frictional coefficients.
The conclusions are indicated that friction can influence the properties of periodic motion, which improves the stability of periodic motion on a certain extent, but produces new instability periodic motion.
Introduction The clearance, time-varying mesh stiffness, sliding friction between meshing teeth are primary factors which effect the dynamics capability and the working reliability in geared systems, while the stability of the periodic motion and bifurcation properties of the system correspond to no-impact, unilateral impact and bilateral impact of the gear system which effect the vibration state and the noise level.
However, it is seldom to consider the friction between gears how it affects the stability of the system [1].