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However, the deleterious effect of hydrogen on the physical and mechanical properties of the pipeline steels needs to be carefully investigated and predicted to ensure safe and reliable pipeline operation under hydrogen pressures in both static and cyclic loading conditions.
The influence of hydrogen on the properties of current pipeline steels depends on the kinetics of absorption, the diffusion rate and the complex interaction of hydrogen with microstructural features present in the steel.
The Cellular Automaton (CA) technique has been used to predict the property degradation of microstructures with various properties (e.g. different grain size) under a given hydrogen embrittlement condition.
Previous work has shown that average grain volume (or average grain diameter) is a significant parameter affecting or controlling hydrogen diffusion because grain boundaries play a twofold role regarding hydrogen diffusion in the microstructure [6].
A 2D space with the given properties should be occupied by the diffusing hydrogen atoms.

Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia.
Introduction Friction stir welded joint (FSW) includes five different zones, shown in Fig. 1 (a) as: (1) nugget zone (NZ), (2) flow arm zone (FAZ), (3) thermomechanically affected zone (TMAZ), (4) heat affected zone (HAZ) and (5) parent plate zone (PZ).
Material property of FSW zones in 2024-T351 Al Alloy.
In fact the crack behavior is intensely affected by the variation of hardness and residual stress along the zones in addition to the microstructure.
On the other hand residual stress as a significant factor in crack behavior increased the growth rate from NZ to TMAZ where it fell from 200 MPa compression to 60 MPa compression.

Several factors affect the performance of a catalyst.
By modeling a converter with proper dimensions and its related properties, it is possible to see the situation that happens during the complicated chemical processes.
Simulation of Catalytic Converter Performance The nature of the exhaust gas flow is a very important factor in determining the performance of the catalytic converter.
Pontikakis: Modeling, Reaction Schemes and Kinetic Parameter Estimation in Automotive Catalytic Converters and Diesel Particulate Filters, Published Thesis, University of Thessaly, Greece: Department of Mechanical and Industrial Engineering (2003)
Nurhafez: International J. of Mechanical and Materials Engineering (IJMME), Vol. 2 (2007), No. 1, p. 1 [5] R.E.

Citation & Copyright (to be inserted by the publisher) Structural and Magnetic Properties of Bottom-up Synthesized ZnFe2O4 Nanoparticles J.
Magnetic and magneto-optical properties therefore arise and are investigated by static measurements performed on individual particles solutions.
However, such applications are dependent on the structural and magnetic properties of the nanocrystals that generally differ from those of bulk materials [2].
The fitting quality is controlled by Rp, Rwp that are reliability factors and χχχχ², the goodness of the fit.
Summary Stoichiometric zinc ferrite nanoparticles have been bottom up synthesized and exhibit very peculiar properties.

Introduction Magnetorheological (MR) materials are smart materials which have MR effects and many unique properties under magnetic fields.
The MR effects are that the rheological properties will be changed under external applied magnetic fields.
MRE is a composite material, whose mechanical properties are changed when external magnetic field is applied.
Thin aluminum plates were chosen for elastic surface plates as follows: (1) Aluminum has low damping properties and relatively high stiffness properties compared to those of MREs; (2) Aluminum’s relatively magnetic permeability equals to zero, which indicates that it does not effect the distribution and strength of the magnetic field.
Considering a MRE cantilever sandwich beam was divided into N regions, the transverse vibration equation is given in the form of: (1) The free vibration response of the cantilever beam is given by: (2) Substituting Eq.2 into Eq.1 for zero external excitation force, the resulting vibration equation can be expressed as: (3) The above equation can be non-dimensionalized by defining: , , Where l is the total length of the beam, ξ is the non-dimensional space variable along the beam length, ωn, βn are the natural frequencies and loss factors of the composite beam, respectively, then the vibration equation with non-dimensionalized parameters becomes:

The formation mechanism and physical properties of high-densification Mo/Cu composites are studied by analyzing materials' microstructure, atom diffusion near the phase interface and physical properties.
The overall properties can also be adjusted by changing the proportion of its components.
The densification of powder metallurgy materials [18] is one key factor affecting the mechanical and physical properties of materials.
The tensile mechanical properties of the materials were tested at 25 ℃ using a CMT5105 electronic universal testing machine.
Sun: The Study on Preparation and Properties of Mo-20wt.

Introduction The use of piezoelectric ceramics in all kinds of smart devices has received considerable attention because of their especially piezoelectric and dielectric properties and their electromechanical, and electro-optical coupling performances.
However, electromechanical combined action is a main factor of fracture in piezoelectric ceramics.
The results show that fracture toughness is anisotropic and the direction of the applied electric field can significantly affect fracture behavior.
When combined electric-mechanical loads were applied, polarized samples were subjected to an electric field and a mechanical load.
Kamiya: Effects of dc Electric Field on Mechanical Properties of Piezoelectric Ceramics.

Parameters Optimization on the Lapping Process of 9Cr18 with Taguchi Method Xiaofeng Zheng1,a, Julong Yuan1,b , Donghui Wen1,c and Feiyan Lou1,d 1 The MOE Key Laboratory of Mechanical Manufacture and Automation, Zhejiang University of Technology, Hangzhou, China, 310032 a shawfun@126.com; bjlyuan@zjut.edu.cn; cwdh_74@163.com; dloufeiyan2002@163.com Keywords: Optimum design, Taguchi method, 9Cr18, Lapping Abstract. 9Cr18 is a type of martensite stainless steel.
Finally, the optimum condition of each factor can be determined that speed: 80rpm, load:3.0kPa, and time distribution: rough lapping time=15min, Ultra-precision lapping time＝45min are the optimum conditions for both Ra and Wt.
In additional, since the lapping process was divided into two steps in the experiment, the time distribution of two steps affected result seriously.
The paper also involved in the vital factor.
Variance of each parameter is: Vk= SSk/Fk, Fk is freedom of parameters , freedom of this reseach is: Fk=3-1=2.The variance of unknown factor (D column inTable 3) is: Ve=SSe/Fe, Fe = 3-1 = 2.

Through FEM analysis of the frame of 170t dump truck and other more structures frame, under the situation of fully loaded condition and lifting condition, the stress level of the bottom steel board of the frame carling and LOCS is one of the important factors of affecting the stress level of the whole frame under the precondition of that structure and shape size of the frame and the frame carling is unchangeable [1,2].
Because only thinking about material elastic property not researching plastic property, the stress peak value appears at 1.8s around, and it is about 989MPa.
Because only thinking about material elastic property not researching plastic property, the stress value reaches about 1424MPa at 6s.
It provides datum support for researching property of LOCS and frame during lifting
Journal of Mechanical Engineering, Vol.45 No.6 (2009), p. 262-266

Both factors are connected by the thermal conductivity (k).
Rigal, Improvement of Thermal Properties of Fired Clays by Introduction of Vegetable Matter, Journal of Building Physics. 34 (2) (2010) 124-142
Gomze, Improvement of Insulation Properties of Conventional Bricks Products, Materials Science Forum. 589 (2008) 1-6
Mohajerani, Physico-Mechanical Properties and Leachate Analysis of Clay Fired Brick Incorporated with Cigarette Butts.
Thermal Insulation–Determination of Steady-State Thermal Transmission Properties-Calibrated and Guarded Hot Box.