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Thermal reduction of graphite oxide is the method used to obtain bulk quantities of graphene platelets (GPL) which comprise multiple graphene sheets.
In this work, thermal reduction of graphite oxide was used to obtain bulk quantities of graphene platelets (GPL) which comprise multiple graphene sheets.
b) a) Fig.2. a) Load-depth response of elastic-plastic material during nanoindentation, b) AFM image of nanoindented Epoxy sample Atomic Force Microscopy (AFM) image of the indented site in epoxy are shown in Fig. 2b The Procedure to Calculate the Hardness and Reduced Modulus: The procedure was developed by Oliver and Pharr [2] to measure the hardness and elastic modulus of a material from indentation load–displacement data obtained during one cycle of loading and unloading.
Reduced modulus, elasticity modulus and hardness of graphene platelet (GPL)-epoxy nanocomposite measured from force-depht curve under load controlled nanoindentation Load (µN) Loading rate (µN/s) Er (GPa) E (GPa) Hardness (MPa) 2000 200 2.86 2.61 174 4000 200 2.22 2.02 135 6000 200 1.79 1.63 118 8000 200 1.63 1.49 112 Conclusions and Comments Thermal reduction of graphite oxide was used to obtain bulk quantities of graphene platelets (GPL).

The influence of size reduction of SrFe12O19 powder particles on magnetic parameters of the studied nanocomposites were discussed in detail.
b) a) Fig. 3 Magnetic data for nanocomposite pellets containing nano Ni and SrFe12O19 (as received and milled) powder versus concentration c: a) saturation magnetization Ms, b) residual magnetism Mr.
It seems, that the size reduction effect results in higher disorder in magnetic moment structure of the strontium ferrite particles, so an increase in (m)SrFe12O19 concentration gives a slight decreases in Ms (from 51 to 46 emu/g, see Fig.3a).
Concluding remarks Main conclusions can be formulated as follows: i) presence of Ni nanopowder in A-E+SrFe12O19 composite improves its elastic properties, e.g. for 36 wt. % of Ni the observed increase of Ea is about 80 % ii) size reduction of the SrFe12O19 powder particles causes an increase of coercive field Hc from 1 to 1.8 kOe and iii) replacement of the as received micron size strontium ferrite particles by the milled ones results in the significant decrease in saturation magnetization Ms and residual magnetism Mr.

The cutting followed by burnishing, used like a combined process, leads to the improvement of the part surface quality (roughness, hardness, microstructure etc.) and to reduction of the costs and manufacturing times as a function of different working parameters.
Introduction The cutting followed by burnishing, used like a combined process, leads to the improvement of the part surface quality (roughness, hardness, microstructure etc.) and to reduction of the costs and manufacturing times as a function of different working parameters.
The burnishing- turning combined process determines the following effects on the machined surface quality: the considerable reduction of the surface roughness, the increase of the material microhardness, the elongation of the material grains in the rolling direction, the occurrence of the compressive residual stresses in the surface layers, the occurrence of the cracks in the surface strata for a pressing pressure of 150 bar [1, 2].
The strain gauges used for determination of residual stresses were of HBM 1.5/120RY61S type, their signal being captured by a SPIDER 8-30 data acquisition device and processed using the Residual Stress Management System.

A comparison between these results and the existing data for conventional high-strength alloys with various surface finishes was difficult since the majority of studies found were performed in the 1930s through the 1950s, using common finishing techniques of the time.
One reference reported reductions in fatigue-endurance limits for comparable finishes of high-strength steels [15].
A general observation is that the reduction is greater for the materials with higher tensile strengths.
Comparing the stress-range/fatigue-life data of notched BMG-11 specimens tested in air with various finishes.
Reduction of fatigue-endurance limit for conventional, high-strength steels, and BMG-11.

PNH1 in combination with NSF improved workability retention with respect to pure NSF, but caused a reduction in the early compressive strength when the dosage exceeded 0.10% (dry polymer vs. cement mass).
The latter are more effective in terms of both water reduction and workability retention as a consequence of a different dispersion mechanism [1,2].
The effect could be explained by considering the intrinsic lower effectiveness in terms of water reduction of pure phosphonate with respect to pure NSF and PCE.
In the case of CEM II/A-LL 42.5R data indicate poor workability retention for both blended PNH1-PNH2/PCE admixtures in comparison with the pure PCE (Fig. 4a).
Finally, lower superplasticizer/cement compatibility, as confirmed by data scattering, was detected for PNH2/PCEs superplasticizers.

Introduction Weight reduction of automotive components is the most effective approach for reducing the carbon dioxide emissions of automobiles and improving their fuel efficiency.
Fig. 5 shows the fatigue data and S–N curves of the strips.
In the stress regime with finite fatigue life, the scatter of data obtained at a given stress level is not large in any of the strips, despite the large deviation in the tensile elongation of the 3-mm-thick strip (Fig. 5a–c).
With an increase in the strip thickness, their fatigue strength gradually decreases because of the reduction in their yield strength.
These results demonstrate that the yield strength, tensile ductility, and fatigue strength of the TRC AZ31 alloy strips improve simultaneously with decreasing strip thickness because of the reduction in the DRXed grain size.

We have studied noise reduction methods using a hybrid Kalman filter with an autoregressive moving average (ARMA) model that the coefficients of the AR models for the Kalman filter are calculated by solving for the minimum square error solutions of over-determined linear systems.
A traditional way to remove noise from image data is to employ spatial filters.
We have studied noise reduction methods using a hybrid Kalman filter with an autoregressive moving average (ARMA) model that the coefficients of the AR models for the Kalman filter are calculated by solving for the minimum square error solutions of over-determined linear systems.
We have studied noise reduction methods using a hybrid Kalman filter with an autoregressive moving average (ARMA) model that the coefficients of the AR models for the Kalman filter are calculated by solving for the minimum square error solutions of over-determined linear systems.

The computational analysis provides useful data on cooling-related issues such as residual stress, shrinkage, warpage [6,7].
Further reduction of this distance could lead to decreased mechanical strength of the mound.
This approach takes the initial flow data to calculate the mould temperature distribution and then uses the temperature information to recalculate the flow solution.
Based on the CFD data, the design of the CCCs was iterated three times until an acceptable flow distribution and velocity were achieved in all branches with a satisfactory pressure drop.
A similar result was achieved for the fixed half with a reduction in the hotspots' temperature from 91 ℃ to 80 ℃.

It was established that the modification with LO leads to increasing of wear resistance and durability of the R6M5 steel because of a double reduction of the friction coefficient.
According to reference data [13, 18] if peak B has a higher intensity than peak A in Fe M2,3VV Auger spectrum, then there is oxide FeO on the surface.
It should be noted that the data on the chemical state of the iron atoms, obtained by both AES and XPS methods are similar.
Certain differences with the XPS data can be understood and explained if we consider that the XPS data are averaged by a sample area about 10 mm2, and the data of Auger electron spectroscopy refer to an area about 3 microns in diameter.
Sidashov, Segregation Processes and Surface Composition of Certain Alloys and Steels in Oxygen Medium by X-Ray and Auger Electron Data, Ph.D. diss., Rostov-on-Don, 2009

This model assumed that the oxygen flux is governed by the association/dissociation of adsorbed oxygen and by the high energetic cost of oxygen reduction/oxidation.
Introduction Due to the increasing need of pure oxygen at high temperature and cost reduction policy in energy industries, catalytic membrane reactors are promising technologies to replace usual cryogenic separation of oxygen form air.
Local hypothesis Thermodynamic balance: - Global reaction OO×+*kS1ex2h∙+O*+ VO× - Reaction mechanism Mathematical relations Dirichlet boundary condition : Neumann boundary condition : Neumann boundary condition: Comparison with experimental data Conclusions Over-estimates the oxygen activity gradient inside the membrane, so overestimates the chemical strains Underestimates the oxygen activity gradient inside the membrane, so underestimates the chemical strains Can reproduce the measures but cannot predict the oxygen permeation fluxes.
The oxidation/reduction reaction describes the charge transfer phenomena.
This model reproduced qualitatively the kinetic difference between oxidation and reduction but it should be refined to obtain quantitative prediction.