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Foam glass composite with good properties was prepared from iron ore tailings as the main raw material by two-steps method in this paper, the characteristics of which was determined by XRD and SEM technologies.
The crystal phase existing in the sample may improve the mechanical strength[5], but easily leads to generate more connection pores in the sample inside.
Fig.4 SEM micrographs of porous in samples The foaming temperature is the key factor to affect the sample quality.
Table 3 shows the effects of various foaming temperature on the sample properties.
Besides, the holding time also has effects on the sample properties even at the same foaming temperature.

The New Method For Power Quality Indices Estimation Ying Hai1,a ,Jingyu Chen2, b 1School of Mechanical and Electrical Engineering, Jiaxing University, Jiaxing 314001, P.R.
To analyze non-stationary PQ variations, other non-parametric methods based on discrete wavelet packet transform (DWPT) has been successfully applied to detect sudden changes in PQ, but Mother wavelet selection is arbitrary and affects the accuracy .
However, these parametric methods requires prespecified information about the frequency of the power signal, and these algorithm measured signals captured from monitoring devices are invariably contaminated by some amount of noise, which affect the accuracy of PQ estimation[1] [2].
ESPRIT is an eigenvalue decomposition-based batch processing technique that exploits the rotational invariance property of signal subspace to determine the frequency components present in the signal.
· RMS values of voltages and currents (20) · The total harmonic distortion(THD)of the voltage and current are as follows: (21) · The active power ( P ) quantifies the average power delivered to the load, and is given by: (22) · The apparent power (S ) is given by , Current distortion power (var): Voltage distortion power (var): (23) Harmonic apparent power (VA): · The line utilization is quantified by power factor (24) Figure 1 shows a schematic block diagram of the proposed PQI estimator.

Soil condition is a major impact factor on the strength of cemented soil.
However, most researches on the elements which affect the cemented soil strength were concluded from the laboratory scale with the samples made in the lab, which cannot truly reflect the mechanical properties of cemented soil in complex geological conditions.
The detailed physical properties of the formation is shown in Table.1.
Table1 Physical properties of foundation soils Order of the layer.
The cement-soil piles in field is a mixture composed of cement soil and soil block, the detailed mechanical characteristics requires further investigate.

During transportation, some factors such as high pressure drop, heat transfer, different velocities, and flow regimes are critical, and they should be considered in the design development of these systems.
The thermo-physical properties of the fluids used in the simulation are presented in Table 1.
Table 1 - Properties of the fluids used in the simulation.
It is noticed changes in the oil velocity at the entrance region strongly affect the velocity profile of the oil/water mixture.
Masters dissertation in Mechanical Engineering, Federal University of São Paulo, São Carlos, Brazil, 143p. 2011.

Introduction The failure of a mechanical component is often a combination of external loading, the manner in which the load was applied, and the stress state present in the sample as a result of manufacture or assembly.
The most common method of failure in manufactured parts subjected to cyclic loading is fatigue. [1] The residual stresses that develop in a part during manufacture or use are one of the most influential factors in determining the fatigue resistance of welded components. [2-5] Common manufacturing methods, e.g. welding, machining, hardening, casting and forging, can all produce residual stresses in the final product. [6-8] Thus, good knowledge of the residual stress profile will lead to more accurate fatigue life prediction [9] and allow the optimization of the welding process parameters.
Discussion The simulated stress redistribution along path A-B (Fig. 4a) predicts the stress changes over a fairly narrow range until the dimensions are within the length of the heat affected zone (x=0.4 for the FE model).
The acquired data as compared to simulations suggests that the critical parameters in determining the extent to which a sample can be sectioned and still produce valid XRD data appear to be the length of material in relation to the size of the heat tint zone (HTZ) produced by the weldment even though heat affected zone (HAZ) is traditionally the most important microstructural feature associated with a change in material properties in welds.
Relaxation is much more pronounced when sectioning perpendicular to the weld bead reduces length along the weld pass and a size factor r was derived from the experimental data.

The main advantages of inorganic material are fluid mechanics performance, high mechanical strength, stability, widely application.
Compost, as the most frequently applied basic materials in BF beds, the properties are high surface area, high water holding capacity and rich nutrition.
Optimal water levels depend on medium, bireactor and other factors.
Above or below an optimum pH range, microbial activity is severely affected [39]. optimum pH range relate with microbial species and odor components.
Therefore, the content of nitrogen in the BFs will directly affect the whole purifying effect.

The GP-zone formation is affected by the ratio between Mg, Zn and Si.
In order to investigate how these processes will affect the aging of 7xxx-alloys in industrial practice, a series of experimental alloys with different compositions of Mg, Zn, Fe and Si were prepared.
A possible explanation in the present system may be that the short dimension, i.e. the thickness of the disk-shaped precipitates does not increase during this stage, and that the surrounding strain field is an important factor in strengthening.
By sufficient attention to these effects of increased silicon content in the alloy, it may be possible to attain satisfactory mechanical properties.
Hatch: Aluminium Properties and Physical Metallurgy: American Society for Metals, Ohio, USA (1984) p.206 [13] M.J.

Experimental tests of hydraulic components in low ambient temperatures were conducted in the hydraulic laboratory of the Faculty of Mechanical Engineering of Gdansk University of Technology.
Startup of a hydraulic system in low temperatures may cause: reduced hydraulic-mechanical efficiency, delayed reaction time of valves, faster wear and more frequent damage to parts (elements) of components, changes in clearance between cooperating elements of components, change of material properties of elements of hydraulic components, increase of flow resistance [1, 2, 3, 16, 17].
Determination of clearance between cooperating elements of component Changes of clearance between cooperating elements of hydraulic components during start-up of the equipment in these conditions depend on many factors.
Use of materials with different properties of thermal expansion coefficient of hydraulic components elements Special design of component Methods of preventing from loss of effective clearance between cooperating elements of hydraulic component Housing of component with higher surface of heat transfer Additional heating of hydraulic component housing Heating of housing with hot fluid Electrical heating of housing Fig. 4.
Design of hydraulic components affects boundary changes of clearances during start-up in thermal shock conditions and thus their behavior in these conditions. 2.

Introduction Diamond films have excellent mechanical and tribological properties, such as high hardness and elastic modulus, good wear resistance, low friction coefficient and thermal conductivity, which make them the best candidates for wear resistant applications.
Since diamond is the hardest material known, conventional mechanical polishing methods are difficult to apply and very time consuming, especially for the complicated shape surface.
Moreover, the adhesion of the coating can be adversely affected since the processing temperature is generally high [1,2].
Moreover, NDFs have lower hardness than conventional diamond films because of the presence of amorphous carbon in the films, and contain a high level of intrinsic stress that directly affects their adhesion on WC-Co substrates.
As compared with the cemented carbide tools and drawing dies, the working lifetime of these diamond-coated tools and drawing dies increases by a factor of 5-10, according to practical cutting and drawing wire tests.

The quasi-static mechanical properties of the concrete are given in Table 1, which are the average values of 5 specimens.
The relative amplitudes of the incident, reflected and transmitted waves, depend on the mechanical properties of the steel bar/concrete specimen.
In numerical study [16], the steel bar/concrete interface with static toughness properties was studied in the dynamic loading.
Effective depth may also have an effect on interface bonding properties.
Kolsky, An investigation of the mechanical properties of materials at very high rates of loading, Proceedings of physics Society, B62 (1949) 676