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Carbothermal Reduction and Nitridation of Quartz Mineral for the Production of Alpha Silicon Nitride Powders A.
In this study, α-Si3N4 powder was produced by carbothermal reduction and nitridation (CRN) of quartz from Can-Canakkale.
The carbothermal reduction method (Reaction 1) starts from a mixture of SiO2 and carbon, which is then reacted to form α-Si3N4 powder between 1400-1500°C in flowing N2 [6-9] or to form SiAlON powders [10].
Data from the chemical analysis and X-ray diffraction showed that the quartz consisted mainly of silica (Table 1).
Conclusions Technological ceramics such as Si3N4 based ceramic powders could be produced easily from widely available raw quartz mineral powders by the carbothermal reduction and nitridation (CRN) process.

After final annealing (circles), the grain diameter is the largest for the rolling reduction of 5%, which means that SIBM occurs most effectively after this specific rolling reduction.
For reductions larger than 5%, grain diameters decrease with increasing rolling reduction..
These data are consistent with the one previously found by Park et al. [6], which also showed that, after 6% strain, the difference of stored energy between Goss and D-Cube orientations was indeed very small.
Concerning the D-Cube orientation, the data of Fig. 3 are thus inconsistent with the fact that this orientation does not develop during annealing (Fig. 2(f)-(h)).
If this idea ( speculated from both experimental data on single crystals and orientation stability analysis) that D-Cube grains have more homogeneous dislocation and orientation distributions than Goss grains, is taken into consideration, our experimental results in terms of texture evolution can then be explained as follows: in the 5% rolled specimen, the Goss and D-cube grains present almost the same lowest stored energy value but Goss grains present a growth advantage due to more heterogeneous microstructures.

Based on an analysis of the experimental data, possible reasons for the enhancement as a result of pre-annealing in the formation of cube orientation grains are discussed.
Despite the large amount of experimental data available, the detailed mechanisms for the development of the cube texture is far from completely clear, and may in fact vary with both alloy and with strain.
Following this idea some experiment data have confirmed that either slow heating and the use of a low temperature "recovery annealing" prior to recrystallization annealing are beneficial for the formation of viable cube recrystallization nuclei [4, 5].
Experimental Methods High-purity nickel (99.999% purity) was cold-rolled to 96% thickness reduction (ε = 3.9).
A detailed inspection of the EBSD data shows that an orientation gradient is observed along each cube band (Fig.2).

This design allows the cup reaction at relatively low gas flow rates to avoid flow limited mode and external diffusion resistance in the processing of experimental data.
Mass loss was recorded at the time, as shown in Fig. 4 (data analyzed by linear approximation).
The data presented in Tab. 1.
Analysis of the reduction processes in the two-dimensional version has been made on the basis of mathematical models of gas dynamics, heat transfer and reduction (Fig. 12a, b).
Analysis of published data revealed that the most important characteristics are reducibility and strength for the iron ore material, the coke reactivity index.

The value of the specific surface area was determined from the data of nitrogen adsorption isotherms observed at 76 K.
Phase composition was analyzed with the use of data bases PCPDFWIN and full-profile analysis program POWDER CELL 2.4 and PDF 4+.
Step-like reduction is typical for all samples.
Based on these data, the reduction temperature for carrying out catalytic research was chosen to be 350 °С.
Reduction in the mixture of hydrogen with argon (10 % vol.

As green roof technology is still emerging, there is limited technical data available at present in Malaysian climate.
(a) (b) (c) Fig. 1: (a) Roof 1 consists the existing green roofs planted with Lantana camara and Orthosiphon samineus; (b) Lantana camara species; and (c) Orthosiphon samineus species The data observed were the temperatures on the top and bottom of the green roof boxes with the ambient temperature.
Temperature data for Roof 1 was observed on 21st November 2013 while for Roof 2 was on 25th February 2014.
However, no meteorological parameters data were observed on that day.
On the other hand, the reduction for Roof 2 was between 7.0°C and 15.0°C or in average 10°C during extreme dry weather.

The experimental results was evaluated by the mass reduction and shrinking core models.
Aluminum with a thicker thickness can be approached with a mass reduction model.
While the mass reduction method examines from surface area and associated with the size reduction rate each time.
In addition, the mass reduction model also consider the purity of the aluminum.
The experimental data will be compared with the mathematical model.

In this paper, we propose a novel MB-OFDM structure and use the frame to transmit data in vehicle-to-vehicle (V2V) communication scenario.
Such services require dependable wireless V2V communications providing robust connectivity at moderate data rates.
The N-point frequency-domain data is divided into G block of length .
Where N corresponds to the IFFT data block length of conventional OFDM.
Finally, choosing data from the last sub-block as guard interval of whole MB-OFDM symbol: (1) Fig. 1 Time-domain frame structure of novel MB-OFDM Fig. 2 Steps to produce a novel MB-OFDM symbol, where [•] denote the size of the data As mentioned above, the difference between MB-OFDM and conventional OFDM is the IFFT-pointer.

Optimization through vibration reduction of amplitude and frequency followed the idea that for the human body very important are the vibrations transmitted in the direction OY, so acceleration and vibration intensity has to be reduced to acceptable values​​.
Due to the vibration intensity reduction, a noise sound pressure diminishing is also expected​​.
Centralized data for vibration characteristics using initial and optimized rim geometry Proper vibration mode Initial supporting structure Optimized supporting structure Amplitude [mm] Frequency [Hz] Vibration intensity [vibrars] Amplitude [mm] Frequency [Hz] Vibration intensity [vibrars] LAeq reduction [%] First proper vibration mode 1.04 245.76 88.65836 2.573333 51.84 57.08882 36.22 Second proper vibration mode 1.1 252.48 89.25343 2.53 55.68 57.94609 34.58 Third proper vibration mode 1.17 302.72 91.88579 1.413333 100.48 63.10874 38.47 Fourth proper vibration mode 6.14 366.4 101.573 1.963333 131.52 68.0436 39.52 Fifth proper vibration mode 7.31 488.32 106.073 4.633333 214.72 78.15902 37.65 Table 2.
Centralized data for vibration intensity using initial and optimized rim geometry Vibration intensity measured using initial rim geometry [vibrars] Vibration intensity measured using optimized rim geometry [vibrars] Degree of diminishing [%] OX direction OY direction OZ direction OX direction OY direction OZ direction OX direction OY direction OZ direction Medium value 99.03 91.93 84.92 67.13 61.45 55.69 32.21 33.16 34.42 Minimal value 83.83 85.79 58.05 53.83 56.19 38.74 35.78 34.51 33.27 Maximal value 104.4 97.33 97.54 69.27 64.95 64.31 33.66 33.27 34.07 Conclusions By optimizing the support structure of sorting and washing stations of mineral aggregates, which can be easily applied in practice by any producer of such equipment, it was obtained a noise reduction (expressed as LAeq [dB], the parameter describing year sound level with the same energy content as the varying acoustic signal measured) of approx. 37.28%.
The vibration intensity measured over the orthogonal axes shows that maximum intensity reduction gained along the of axis, stipulated in the standards as the most dangerous propagation direction of vibrations for the human body, the value of the vibration intensity is 32.38 vibrars, that represents 33.27% reduction.

Thermal errors can be predicted and compensated for by using mathematical models that apply data from a number of temperature points related to the increase of thermal errors and incorporating these errors within the general volumetric error model to form a synthesized model [3, 4].
The thermally induced volumetric error prediction accuracy of the model proposed above was verified by simulation results based on publically available data [7].
The measurement refers to datum plane B, which is the origin of the WCS.
The reduction of positioning errors by compensation is summarised in Table 2.
The absolute reduction of the positioning errors of drilled holes was an average 30.44 μm at the thermal stable stage, while the average relative reduction ratio of these errors was 77%.