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The solution of both problems of fluid flow and metal plastic flow provide fields of velocities, pressure and temperature, and provides important data about materials flow pattern [7,11].
In this work, the numerical scheme presented by Martins et al. [16,17] was applied to analyse the work zone of aluminum axisymmetric direct extrusion in a 90° die with a reduction ratio of 8.0.
Parameters Values Yield Strength (sY) 80 (MPa) Deformation (e) 87.85 % Initial Velocity (v0) 2.5 (mm/s) Initial Strain Rate () 0.9 (s-1) Time Step (∆t) 10-15 (s) The main contribution of present work is to demonstrate that the numerical scheme previously developed in [16,17] can also describe the dead zone of metal plastic flow in axisymmetric direct extrusion in a 90º die and with a reduction ratio of 8.0.
Conclusions From the results and analysis of aluminum axisymmetric direct extrusion in a 90º die by present FVM , using a fixed Eulerian mesh, the following conclusions can be outlined: § from the axial velocity contours calculated by present FVM, the dead zone could be observed, i.e., present numerical scheme has succeed to capture the dead zone which is the region where the axial velocity is very small near the 90o die wall in direct extrusion; § the dead zone calculated by present FVM is smaller than calculated by slip-line field theory; § the axial velocity increased its magnitude from external layer to the central region line inside the billet as expected; § the radial velocity increased its magnitude on the die wall where the area reduction occurs, and the billet deformation takes place; § the biggest calculated pressure occurred at the inlet deformation region of extrusion; § the die wall around the corner in the reduction exit area shows the highest effective strain rate

In order to achieve the aim of sustainable development, the transformation to a low carbon society has becoming a revolution for all the countries, especially the developing ones, who will bear the brunt of the climate change effects because of lack of the capability to adapt, and the establishment of reduction target of the greenhouse gas emission has brought them great pressures.
LCT is generally divided into two categories, one is the reduction techniques in the field of energy consumption, including the four main sectors of production and circulation, transportation, construction and residential, family, the other is the reduction techniques in the field of the supply of energy, including fossil fuel energy sector, new energy and renewable energy sectors [2].
There is no data to indicate that low-carbon technology infringement cases exist in developing countries.
With the continuous rise of global temperature, and the commitment on carbon emission reduction, the low-carbon technology is the most effective way to stabilize climate change.

BET surface area and pore volume of monolith silica was at 588.0148 m2/g and 0.895424 cm3/g respectively compared to both hybrid silica which shows a significant reduction at which surface area and pore volume was in the range of 25 - 120 m2/g and 0.04 - 0.2 cm3/g respectively.
This behavior was interpreted taking into account the surface organic coverage of the pores that results in a partial reduction in the pore free volume and according to the literature, the pore blocking effect occurs preferentially in the larger pores [14,15], as observed in the present work.
Table 2: Porosity data of monolith silica and hybrid silica xerogel samples determined from nitrogen (N2) adsorption-desorption test method Sample type BET- Surface area (m2g-1) BJH -Total Pore volume (cm3g-1) BET- Average Pore size (nm) Monolith silica 588.0148 ± 0.6639 0.895424 5.70976 Hybrid silica 1 119.5905 ± 0.3078 0.203957 6.51034 Hybrid silica 2 25.7887± 0.1714 0.043967 6.59728 The addition of more calcium oxide into silica matrixes has increased the reduction of the surface area.
The reduction of total surface area was directly affect the pore volume of the samples which shows similar trend as decreasing in total surface area contributes to decreasing in pore volume.

Thickness [mm] Rm [MPa] Rp 0,2 [ MPa] Elongation A Lo=50mm [ %] Reduction [%] True reduction [ε] 7,5 93,5 63,5 37,0 5,0 117,8 114,5 15,5 33,3 0,41 3,0 146,1 136,0 11,3 60,0 0,92 2,0 161,3 150,3 5,0 73,3 1,32 1,0 169,4 161,3 4,3 86,7 2,01 0,50 177,9 160,0 3,3 93,3 2,71 0,20 206,0 190,0 2,5 97,3 3,62 Table 5.
Thickness [mm] Rm [MPa] Rp0,2 [MPa] Elongation Lo= 50mm [%] Reduction [%] True reduction [ε] 3,0 96,5 70 30 2,0 125,2 114 7,7 33,3 0,41 1,0 133,1 124 6,7 66,6 1,10 0,50 152,0 145 3,1 83,3 1,79 0,20 189,6 180,0 3,6 93,3 2,71 Fig. 1.
Table 6 is built with the data values shown in Tables 4 and 5.

Due to the slow rotation rate of the cube orientation the resultant 0°/90° ears are able to balance the newly forming 45° ears up to rather high rolling reductions.
Because of the high deformations and temperatures involved in breakdown rolling, the material readily recrystallizes statically between passes, which results in a reduction in grain size and a fairly mild cube recrystallization texture.
In the following tandem line hot strip is produced on 3 or 4 connected rolling stands in steps of the order of 50% thickness reduction.
The required microchemistry data, including the concentration of solids as well as size and density of second-phase particles were provided by a microchemistry model ClaNG [15].
Accordingly, here the range with suitable Z and ∆Z earing values is shifted towards smaller reductions (Fig. 6), where the materials strength is usually not sufficient. 0.0 0.5 1.0 1.5 2.0 2.5 -10 -5 0 5 10 Z ∆Z 100% 20% 20% rolling degree 0% 50% 75% 85% 92% Z ∆Z 0% 5% 100% 0% 0% Z, ∆Z [%] ε Fig. 6.

The climatic data (period of 1989-2015) show that the average monthly temperature varies between 11.39°C (in January) and 32.78°C (in July).
It can be observed that the reduction of Ntot content is important in all filtered water samples.
The percentage of TSS reduction reaches 94.76% and 96.28% using the vegetated filter and unplanted control, respectively.
Results show that the maximum percent of TP reduction reaches 98.65 % (in February) and 95.50 % (in April) using Juncus maritimus filter and unplanted control, respectively.
Tondee, Constructed Wetland for Sewage Treatment and Thermal Transfer Reduction, vol. 79, no.

The fracture strain was increased significantly with the increase of solution time, indicating that the ductility of the composites was greatly increased due to the reduction of brittle β phase and coarse eutectic τ phase.
Meanwhile, the reduction of the β phase resulted in a decrease in hardness after solution treatment.
Fig. 6 (a, b) Polarization curves of the composites in different processing status in 3 wt.% KCl solution, (c) electrochemical data obtained from the polarization curves Summary In summary, the effects of solution and aging treatment on the microstructure, mechanical properties and degradation behavior of the HGM/MA composites were evaluated.
The increase in the UCS was attributed to the solution strengthening of Al and Zn elements, while that in ductility was attributed to the reduction of the reticular β phase and coarse τ phase.
The decrease in the hardness and degradation rate was attributed to the reduction of the β phase.

The reduction in casting variations allows a reduction in machining allowances, which will lower the down stream cost.
The addition of 3 % Mg to Al melt reduces its surface tension to (0.62 Nm-1) at 720 ⁰C, the reduction is about 30 % from its original value [14].
Coating by metallic powder can be achieved by: spray drying, chemical processes (hydrochemical reduction), sol /gel processes etc.
Keene, "Review of data of surface tension of pure metals", Intern.

In the controlled rolling process, two stages of rolling (rough rolling and finish rolling) are usually adopted, and large reduction ratio of thickness during this process is essential for pipeline steel [5].
Fig. 3 shows the experimental data obtained via EBSD.
It is well-known that the AF generally nucleated intra-granularly on the crystal defects, i.e. dislocation, deformation band, and large enough reduction ratio, high cooling rate, and low cooling-interrupt temperature are essential for AF transformation [13, 14].
Based on the TMCP stated above, large reduction ratio (52%) during finish rolling and high cooling rate (35℃/s) obtained through UFC were adopted, which increased the nucleation sites and improved super-cooling degree of AF transformation.
Hence, the certain volume fraction of AF for 350℃-processed pipeline steel was attributed to the large reduction ratio and high cooling rate after rolling.

Data indicates about the essential affect of large diameter pipe steel quality and properties on quantity and length of their damages.
Controlled rolling is the most economical method of steel sheet for gas pipe mains and ensures the required level of properties by microstructure size reduction without additional heat treatment.
At present time the high quality pipe steel sheet can be obtained by thermomechanical rolling which provides control of heating temperature, temperature and reduction at rolling, and cooling after rolling.
One of the main tasks of hot rolling process is to ensure the stable course both of the rolling technology and sheet coiling at the rolling mill in the required temperature and reduction regimes and to obtain the desired quality of rolled sheet.
The input variables are mechanical properties and parameters of the microstructure, which, depending on control variables (reduction in rough and finish group of stands, temperature of rolling and cooling), will vary after hot rolling and can be expressed through the values of output variables.