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Evaluation of Optical Properties for Nanocrystal Si Dot Layers Fabricated by CVD as a Function of Size Reduction Y.
Introduction It is well known through previous study that crystal property is modified drastically with the crystal size reduction.
Moreover, the compressive stress induced by the SiO2 surroundings can be determined by the deviation of the peak shift between the raw data and the calculation.

In the present research, a series of AZ80 magnesium alloy billets were compressed with 60% height reduction on hot process simulator at temperatures of 473,523,573,623,673,723K under strain rates of 0.001, 0.01, 0.1,1 and 10s-1.
Cockcroft and Latham hasn’t expounded whether the critical damage factor depends on the temperature and strain rate [9-10].In this study, for AZ80 magnesium alloy, the relations between critical damage factor and temperature and strain rate were analyzed based on a series of compressing tests data and damage data by numerical computation.
Furthermore, a concept about incremental ratio of Cockcroft-Latham damage in plastic deformation () is brought out and defined as the ratio of the damage increment at one step () to the accumulated value (): (2) True stress-strain data collected at different temperature under different strain rate from the thermal compression experiment of AZ80 alloy were inputted into the custom materials library of the finite element software Deform-3D.
Fig.2 shows the damage distribution at the last step (height reduction of 60%) at 573Kand strain rate of 0.0l s-1.From the simulation results, it can be seen that the maximum damage value appears in the region of upsetting drum, while the minimal value appears in the middle region.
Fig.2 Damage distribution at last step (height reduction of 60%) at 573Kand strain rate of 0.01 s-1 Table.1 Critical damage factor at different temperatures and different strain rates (a) =0.01s-1 (b) =0.1s-1 Fig.3 Incremental ratio varying of Cockcroft-Latham damage during compressing process at different temperatures and different strain rates The mechanical behavior of the material during the hot processing can be described by constitutive equations containing flow stress (σ), strain (), strain rate () and deformation temperature (T).

Thermocouple measurements were made at six locations (top, centre bottom, near the tool and at distances of 10, 20, 30 mm, at the plate centre line) to provide data for calibration of a thermal model.
This point can then be used to fit an exponential torque - rotation rate decay curve to experimental data (Fig. 1a) from which the welding power curve can be derived (Fig. 1b).
Fig. 1 (a) Exponential torque decay curves as a function of rotation rate, ω, fitted to experimental data and (b) the related welding power curves.
There is also a lower reduction in through-thickness hardness within the weld nugget, which is close to being symmetrical around the plate mid-plane.
The SS-FSWs can be produced with a lower heat input, which is more uniform through thickness, and have an exceptional surface finish, with little reduction in section thickness, as well as a narrower weld profile, which results in lower levels of distortion and a reduced HAZ width.

Increasing safety in the structural engineering design of buildings, bridges, parking decks, tunnels, and offshore structures requires high quality experimental data and reliable modeling of the stress-strain relationships of sulfate affected-damaged concrete.
The compressive load and axial deformation data was recorded by data logger and installed to the computer.
Since the internal craking on concrete can be identified by relative dynamic elastic modulus, and the measuring of relative dynamic elastic modulus is very easy to carry on the existing structures, then the reduction of compressive strength, the reduction of modulus of elasticity and the increasing of strain at peak stress of concrete exposed to sulfuric acid in this study were formulated as a function of relative dynamic elastic modulus.
The proposed stress-strain relationship was based on the experimental data tested on this study.
The results showed good correlation with the experimental data.

Sintering time and temperature are important for this research, since the anatase phase of TiO2 has been shown to offer superior photocatalytic properties [6] and DSSC efficiencies [7], but can be converted to the rutile phase at high sintering temperatures, especially after an extended sintering process; and although moderate rutile concentrations can improve the efficiency, beyond a certain concentration the net effect is a reduction in the device efficiency, which is shown at the extreme end of our data range.
The data presented is the average of five (for I-V or J-V) and three (for EIS and OCVD) runs on each of the sample cells, which were then averaged across each batch for accurate representative data.
The cell efficiency (η) and fill factor were determined from the raw current/voltage data from the following equations: η= ImpVmpIvA Fill factor FF= ImpVmpIscVoc Here Imp, & Vmp, represent the peak power current and voltage, Iv, & A, the incident cell irradiance and area, and Isc, & Voc the short circuit current and open – circuit voltage respectively.
J-V plots for samples of the formulation doped with lanthanum at 2.00% and sintered at temperatures ranging from 300°C to 600°C are shown in figure 2, and parametric data are included in table 2 below.
Although the range of sintering temperatures for this dataset did not extend all the way to 600°C, the plot of electron lifetime (obtained from semi-circular fits to the data in figure 4 (a)) versus sintering temperature in figure 4 (b) seems to show that the ideal temperature for producing optimized cells would occur at a midrange temperature above 300°C, but below 500°C, in keeping with the previous results presented from the study.

The elastic micro-mechanical features of individual phases were derived from grid indentation data measured on selected samples (Ti 700 series, Hysitron Inc.).
Indentation moduli of individual phases were derived from normalized histograms of the measured data using spectral deconvolution.
The histograms were cleared from incorrectly measured data, caused by human error or environmental conditions.
Overall effective micro-mechanical features were determined from merged, independently processed data of both material levels.
Collected data of this particular study (microscale investigation of material homogenization) are to be further used in material simulation of the composite.

By means of XPS software analysis (XPS XI-SDP Spectral Data Processor v2.3) and comparing the proportion of the peaks area, the relationship between Ca, O and P were obtained.
The resulting data is shown in Table 1, comparing with proportion of Ca and P in the initially used GC particles and in crystalline HAp.
Nevertheless it is important to note that C30 presents an increase in current density after extend immersion in SBF indicating some grade of weaken, while C10 shows a reduction in current density after 30 days of immersion in SBF (when compared with the sample C10 after 1 day of immersion) showing a better corrosion resistance or an area reduction due to the increase of deposits onto the surface.
Nevertheless C30 coating presents a reduction on its protective character, showing lower resistance when increasing immersion time..
This is in good agreement with the previously shown potentiodynamic experiments, where an increase in current density was observed for C30 samples while a reduction of current density was observed for C10 samples.

Young's modulus E (GPa) 210 Yield stress σy (MPa) 580 Tensile strength σb (MPa) 735 Percentage reduction of area φ (%) 37.6 crack initiation for different processing conditions.
Using the finite element method (FEM), we simulated the stress and strain behaviors in the processed shaft in the vicinity of the diameter-enlargement section during processing, and calculated an elasto-plastic stress concentration factor, an elasto-plastic strain concentration factor, and a fatigue strength reduction factor.
Unprocessed specimen (literature data [6]) Processed specimen (predicted value) Experimental results Fig. 11 Fatigue curve.
Summary The present study has clarified the mechanism of fatigue crack generation during the diameter-enlargement method processing, and evaluated the conditions of fatigue damage of a processed shaft using the fatigue strength reduction factor.
[8] The Japan Society of Mechanical Engineers, JSME Data Book: Fatigue of Metals, 4, Low Cycle Fatigue Strength, Maruzen Publishers, (1983) 9-15, 147, 179.5.293e+002 3.216e+002 1.139e+002 -9.383e+001 -3.015e+002 -5.092e+002 -7.169e+002 -9.246e+002 -1.132e+003 -1.340e+003 -1.548e+003

Constraints for voltage-reduced energy saving Motor efficiency factor The efficiencies of an induction motor running at the same load: (2) (3) Wherein Formula (2) is for the efficiency of light-load voltage reduction (LLVR) and Formula (3) is for that of light-load rated voltage.
Considering the changes in these two factors, according to Formula (7) we have the following conclusions: not all voltage reduction can achieve the desired purpose, and only when the degree of such voltage reduction is greater than that of the slip and power factor increasing, the operating efficiency of the motor can be improved.
Fig. 5 Voltage and current waveforms when no load at 20Hz Fig. 6 Voltage and current waveforms when voltage-reduced no load at 20Hz Fig. 7 Voltage and current waveforms when 30% rated load and voltage reduction at 20Hz By comparing Figure 5 and 6 it can be seen clearly that, in addition to the voltage and current phase angle changing, the line voltage Uab from the inverter and the motor phase current ia when voltage-reduced energy-saving no load, decline substantially compared with those at no load, achieving voltage-reduced energy saving and improved power factor under no-load condition.
The experimental data, without and with the LFES method, are shown respectively in Table 1 and 2.
Tab.Ⅰ The experimental results of motor running at different load without LFES Rated load factor Voltage / V Input power / W Efficiency / % Power factor 1 380 2865.42 85.5 0.81 0.8 380 1996.38 86.1 0.77 0.6 380 1563.05 74.64 0.68 0.4 380 1187.58 72.59 0.5 0.2 380 987.81 69.12 0.4 Tab.Ⅱ The experimental results of motor running at different load with LFES Rated load factor Voltage / V Input power / W Efficiency / % Power factor 1 380 2865.4 85.5 0.81 0.8 345 1990.59 86.5 0.798 0.6 315 1485.33 85.3 0.71 0.4 289 1089.27 83.1 0.62 0.2 268 825.36 80.2 0.55 From the experimental data listed in the two tables it can be seen that, when the motor runs in the vicinity of the rated load, with and without LFES, little change occurs in both its efficiency and power factor, which shows the energy-saving effect is not obvious; along with the rated load factor (a ratio between the load power and rated power) declining, its operating efficiency is gradually improved, also its power factor increases

Therefore, the comprehensive reduction of compressor noise, based on the basic noise control theory, is supposed to be conducted on the three kinds of noise from three aspects: the source, transmission and radiation.
The general equation of noise reduction is given by: (Eq.1) Where is the actual sound insulation of the compressor, is the average sound insulation of the acoustic enclosure, and is the sound insulation coefficient of the acoustic enclosure.
Table 1 Different absorption coefficient of melamine’s different thickness Thickness(mm) Octave band center frequency/Hz NRC 125 250 500 1000 2000 4000 30 0.12 0.31 0.66 0.86 0.87 0.92 0.70 40 0.12 0.44 0.87 0.96 0.97 0.97 0.80 50 0.28 0.63 1.06 1.08 1.05 1.01 0.90 Where NRC is noise reduction coefficient.
Based on the analysis of the peak data of the compressor’s sound power spectrum, the acoustic structure design of the acoustic enclosure should be focused on the compressor’s medium and low frequency characteristics.
The measured results In order to guarantee the feasibility of the experimental data the experiment is conducted in a semi-anechoic indoors which can ignore background noise under the normal operation of the compressor.