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Online since: December 2012
Authors: M.Z.M. Zamzuri, W. Rahman, Z. Nooraizedfiza, M. Marina, Mohd Asri Selamat, K. Alir
The data obtained shows that the Fe-Y2O3 composites samples possessed superior hardness value with the increasing quantity of reinforcement compared to the unreinforced Fe composite.
From the experimental results observed in Figure 2, it shows that the presence of reinforcement particulates caused reduction of sintered densities.
This is supported by a study elsewhere that the addition of Y2O3 particulates as reinforcements into MMCs resulted on the reduction of grain size, which gives better mechanical properties than unreinforced matrix [10].
Experimental data showed that the hardness values increases while the density decreases with the increasing percentage of Y2O3 in the Fe-Y2O3 composites.
From the experimental results observed in Figure 2, it shows that the presence of reinforcement particulates caused reduction of sintered densities.
This is supported by a study elsewhere that the addition of Y2O3 particulates as reinforcements into MMCs resulted on the reduction of grain size, which gives better mechanical properties than unreinforced matrix [10].
Experimental data showed that the hardness values increases while the density decreases with the increasing percentage of Y2O3 in the Fe-Y2O3 composites.
Online since: February 2012
Authors: M.J. Reig, Miguel Angel Selles, S.R. Schmid, Samuel Sanchez-Caballero, E. Pérez-Bernabeu, Vicente Jesús Seguí
A design-of-experiments matrix was prepared using the commercial software package Stat-Ease, and involved varying the die angle, speed, reduction in thickness and tooling temperature.
Variables Units Die angle DA º Punch speed PS m/s Reduction RD % Temperature T ºC The four process variables shown in Table I have been used for DOE realization.
Process variables Sensitivity Die angle º 0.155 Punch speed m/s 0.059 Temperature ºC 0.003 Reduction % 0.001 Die angle is the most influent input variable as can be seen.
This is consequent with experimental data.
Conclusions It has been experimentally shown the validity of the model presented in this work, obtaining coincident results for both methods (theoretical modelization and experimental data), proving the statements held in this paper.
Variables Units Die angle DA º Punch speed PS m/s Reduction RD % Temperature T ºC The four process variables shown in Table I have been used for DOE realization.
Process variables Sensitivity Die angle º 0.155 Punch speed m/s 0.059 Temperature ºC 0.003 Reduction % 0.001 Die angle is the most influent input variable as can be seen.
This is consequent with experimental data.
Conclusions It has been experimentally shown the validity of the model presented in this work, obtaining coincident results for both methods (theoretical modelization and experimental data), proving the statements held in this paper.
Online since: November 2012
Authors: Feng Lan Zhao, Lei Zhang, Ji Rui Hou
Under each group of production pressure, repeated flooding 3 pieces of core, recording flooding data of each core, and then fitting normalization.
With the pressure increasing further, the extent of viscous fingering was increased by the pressure of displacement front increasing, this negative effect exceeded theeffect ofviscosity reduction by CO2, so the extent of viscous fingering was gradually increased.
The data of gas permeability in each measure pressure points in plugging experiment were in table 2.
From the table 2, the permeability was reduced greatlyat a distance from the injection end within 60cm after plugging, amongthe 20-40cm distance, the reduction of permeability was the largest, the residual resistance coefficient was 74.36.
The results made the porosity and permeability reduction, flow resistance increased dramatically in gas channeling passage.
With the pressure increasing further, the extent of viscous fingering was increased by the pressure of displacement front increasing, this negative effect exceeded theeffect ofviscosity reduction by CO2, so the extent of viscous fingering was gradually increased.
The data of gas permeability in each measure pressure points in plugging experiment were in table 2.
From the table 2, the permeability was reduced greatlyat a distance from the injection end within 60cm after plugging, amongthe 20-40cm distance, the reduction of permeability was the largest, the residual resistance coefficient was 74.36.
The results made the porosity and permeability reduction, flow resistance increased dramatically in gas channeling passage.
Online since: September 2014
Authors: Mykola I. Sotnyk, Serhii Sapozhnikov, Kateryna Prykhodko
In conditions of the actual production, this indicator may be determined by the data of meters at any given time.
Reducing the diameter up to 865 mm (on 15% from the initial) results in a reduction in pump efficiency at the optimal consumption point for about 5%.
Further reduction in diameter results in additional energy losses in the impeller and outlet, which reduces the pump efficiency coefficient on 12% if = 805 mm.
Variation range of characteristics of pump D6300-80-22 while reduction of its outside diameter within the range 1020 … 805 mm The results of numeric experiments and conducted field tests on operating site confirm the possibility of stable operation of the said pumps in mode of consumption from 0.6 to 1.2 , but in this case the change in the pump efficiency coefficient is beyond the value - 5%.
Obtaining the necessary input data for its calculation requires no additional tools besides meters of electric energy consumed by drive motors, meters of pumped liquid and manometers, which water supply system are usually equipped with.
Reducing the diameter up to 865 mm (on 15% from the initial) results in a reduction in pump efficiency at the optimal consumption point for about 5%.
Further reduction in diameter results in additional energy losses in the impeller and outlet, which reduces the pump efficiency coefficient on 12% if = 805 mm.
Variation range of characteristics of pump D6300-80-22 while reduction of its outside diameter within the range 1020 … 805 mm The results of numeric experiments and conducted field tests on operating site confirm the possibility of stable operation of the said pumps in mode of consumption from 0.6 to 1.2 , but in this case the change in the pump efficiency coefficient is beyond the value - 5%.
Obtaining the necessary input data for its calculation requires no additional tools besides meters of electric energy consumed by drive motors, meters of pumped liquid and manometers, which water supply system are usually equipped with.
Online since: October 2011
Authors: Ji Tan Guo, Rui Zhang, Rui Wang
The test shows that the noise reduction of OGFC is 5.3-8.7dB at different speed.
Aggregate Gradation Air-void is key factor effecting noise reduction results and drainage.
Research in Japan shows that noise reduction result of NMAS with13mm is the best with the same thickness of 50mm.
Summary of experimental data modified asphalt is shown as Table 2.
Table 2 Summary of experimental data modified asphalt modifier Content (%) Shear temperature (˚C) Shear time (min) Penetration 25˚C (0.1mm) Ductility 25˚C (cm) Softening Point (˚C) SBS 6 180 60 57.2 195 63 rubber 18 170 90 56.4 204 61 EVA 5 160 45 60.8 88 63 PVC 9 180 60 57.7 171 60 Ordinary asphalt 67.6 100 46 Asphalt-aggregate ratio The mixture should can reduce rut, resist freezing crack, water damage and fatigue, ensure air-void, mix and construct easily.
Aggregate Gradation Air-void is key factor effecting noise reduction results and drainage.
Research in Japan shows that noise reduction result of NMAS with13mm is the best with the same thickness of 50mm.
Summary of experimental data modified asphalt is shown as Table 2.
Table 2 Summary of experimental data modified asphalt modifier Content (%) Shear temperature (˚C) Shear time (min) Penetration 25˚C (0.1mm) Ductility 25˚C (cm) Softening Point (˚C) SBS 6 180 60 57.2 195 63 rubber 18 170 90 56.4 204 61 EVA 5 160 45 60.8 88 63 PVC 9 180 60 57.7 171 60 Ordinary asphalt 67.6 100 46 Asphalt-aggregate ratio The mixture should can reduce rut, resist freezing crack, water damage and fatigue, ensure air-void, mix and construct easily.
Online since: June 2008
Authors: Bijan Mohammadi, Hossein Hosseini-Toudeshky, Mohammad Homayoun Sadr-Lahidjani, Shahram Aivazzadeh
It depends on the material characterization which is
performed using the shear or normal stress experimental data.
The i th eigenvalue, φi, represents the effective fractional reduction in load carrying area on planes that are perpendicular to the ith principal material direction as shown typically in Fig. 1.
The Y2 and Y3 are eigenvalues of damage conjugate force tensor defied in Eq. (3) The J11, J22 and J33 are determined by available data on a single composite lamina, and K0 is the initial damage threshold.
The predicted results for [30/-30]2s lay-up based on all damage and coupled damage-plasticity in old and new approaches show higher stiffness reduction with respect to the experimental results.
However, the obtained damage and damage-plasticity results based on the new approach predict the lower stiffness reduction when compared with the old results and they are in better agreement with the experimental results.
The i th eigenvalue, φi, represents the effective fractional reduction in load carrying area on planes that are perpendicular to the ith principal material direction as shown typically in Fig. 1.
The Y2 and Y3 are eigenvalues of damage conjugate force tensor defied in Eq. (3) The J11, J22 and J33 are determined by available data on a single composite lamina, and K0 is the initial damage threshold.
The predicted results for [30/-30]2s lay-up based on all damage and coupled damage-plasticity in old and new approaches show higher stiffness reduction with respect to the experimental results.
However, the obtained damage and damage-plasticity results based on the new approach predict the lower stiffness reduction when compared with the old results and they are in better agreement with the experimental results.
Online since: May 2012
Authors: Xian Jun Ji, Guo Qiang Ou, Jun Wang, Shun Yang
In the 1990s, under the impetus of the "International Decade for Natural Disaster Reduction", Chinese study of geological disaster reduction and prevention had entered a new stage of development, risk assessment models of single gully and regional debris flow had also established [7-10].
The industry of disaster reduction has basically formed involving multi-sector, multi-level and diversified investments.
Mainly manifested in the following areas: Fully realized geological disaster phenomena and patterns of its activity, through a series of investigation, basically indentified the regional distribution of disaster, conducted a disaster zoning and posed corresponding reduction measures [20].
Proposed the new concept of natural disaster system, explored the natural disaster forecasting, and carried out a more detailed observation and monitoring accumulating a large amount of original data.
For example, lack the support of basic data and disaster information processing capacity, and means of information exchange and transmission is relatively backward.
The industry of disaster reduction has basically formed involving multi-sector, multi-level and diversified investments.
Mainly manifested in the following areas: Fully realized geological disaster phenomena and patterns of its activity, through a series of investigation, basically indentified the regional distribution of disaster, conducted a disaster zoning and posed corresponding reduction measures [20].
Proposed the new concept of natural disaster system, explored the natural disaster forecasting, and carried out a more detailed observation and monitoring accumulating a large amount of original data.
For example, lack the support of basic data and disaster information processing capacity, and means of information exchange and transmission is relatively backward.
Online since: August 2015
Authors: Priyono Priyono, Agus Subagio, Pardoyo Pardoyo, Aswardi Aswardi, R. Yudianti, A. Subhan, E. Taer
From the data processing results obtained the difference value of specific capacitance (CS) of each particular frequency variations in the supercapacitor, which was presented by the graph in Fig. 4.
Based on the data obtained specific capacitance (CS), the greatest value of the CS of the AC-MnO2-CNT composite in pH condition of acid, neutral and alkaline were 7.86, 0.93 and 0.55 F/g, recpectively.
Measurement of specific capacitance that occurs in acidic reaction condition increased significantly compared to neutral and alkaline state was related to the formation of MnO2 cathodic reduction reaction.
In reaction to the atmosphere slightly acidic and neutral atmosphere, ion MnO4- with +7 oxidation number would be reduced to MnO2 precipitate with oxidation number +4, while in a state of MnO4- alkaline ions would be reduced to manganate (MnO42-) which was described by the following reaction: 1) The reduction reaction MnO4- acidic condition: MnO4- + 4H+ + 3e MnO2 + 2H2O 2) The reduction reaction MnO4- neutral condition: MnO4- + 2H2O MnO2 + 4OH- 3) The reduction reaction MnO4- alkaline condition: MnO4- + 4OH- 4MnO42- + 2H2O +O2 This reaction has been evidenced from the XRD pattern of AC-MnO2-CNT composite that the presence of MnO2 has the greatest intensity was at the AC-MnO2-CNT composite in acidic conditions.
Based on the data obtained specific capacitance (CS), the greatest value of the CS of the AC-MnO2-CNT composite in pH condition of acid, neutral and alkaline were 7.86, 0.93 and 0.55 F/g, recpectively.
Measurement of specific capacitance that occurs in acidic reaction condition increased significantly compared to neutral and alkaline state was related to the formation of MnO2 cathodic reduction reaction.
In reaction to the atmosphere slightly acidic and neutral atmosphere, ion MnO4- with +7 oxidation number would be reduced to MnO2 precipitate with oxidation number +4, while in a state of MnO4- alkaline ions would be reduced to manganate (MnO42-) which was described by the following reaction: 1) The reduction reaction MnO4- acidic condition: MnO4- + 4H+ + 3e MnO2 + 2H2O 2) The reduction reaction MnO4- neutral condition: MnO4- + 2H2O MnO2 + 4OH- 3) The reduction reaction MnO4- alkaline condition: MnO4- + 4OH- 4MnO42- + 2H2O +O2 This reaction has been evidenced from the XRD pattern of AC-MnO2-CNT composite that the presence of MnO2 has the greatest intensity was at the AC-MnO2-CNT composite in acidic conditions.
Online since: August 2014
Authors: Bao Cheng Li, Zhi Min Zhang, La Feng Guo, Zhi Heng Li, Pan Yu Chen
It provides detailed data of physical quantities during the forming process and reference for tool design and equipment selection.
Hot rolling stress-effective field The reduction of oval pass is the maximum in the bar hot rolling pass system, and its deformation is the most obvious.
As shown, the position of maximum reduction is the position of maximum equivalent stress, as 110MPa, less than the ultimate strength of 150Mpa [8], it can remain stable deformation rolling.
The reduction of oval pass is largest so that oval pass has maximum rolling force, and the maximum rolling force is 54.8kN.
Analysis (1) Rolling force To combine actual data and simulation results, the comparative analysis between rolling force simulation and measured values of oval-vertical elliptical-round pass at stable rolling stage is obtained, see Figure 6.
Hot rolling stress-effective field The reduction of oval pass is the maximum in the bar hot rolling pass system, and its deformation is the most obvious.
As shown, the position of maximum reduction is the position of maximum equivalent stress, as 110MPa, less than the ultimate strength of 150Mpa [8], it can remain stable deformation rolling.
The reduction of oval pass is largest so that oval pass has maximum rolling force, and the maximum rolling force is 54.8kN.
Analysis (1) Rolling force To combine actual data and simulation results, the comparative analysis between rolling force simulation and measured values of oval-vertical elliptical-round pass at stable rolling stage is obtained, see Figure 6.
Online since: May 2014
Authors: Jian Wei Wang, Kai Chang, Xiang Lei Yu
When the factory bound and noise-sensitive structures distance less than 1 m, indoor plant boundary environmental noise measurement noise sensitive buildings should be in, and the corresponding reduction of noise emission limits 10dB (A) as a basis for evaluation.
Factory premises equipment generally more and azimuth, working time, there is uncertainty in the open, therefore, in order to obtain scientific, high accuracy data, you need to choose a reasonable period of time to ensure that all measuring devices may generate noise are in the open state, and recorded under the orientation of the device.
Figure 2 Factories and noise distribution factory out environmental assessment point pressure data.
Table 1 Environmental assessment point total sound pressure level table Noise source code 1 2 3 4 5 6 7 8 A-weighted sound pressure level (dB) 82 80 92 89 84 90 88 87 factory out environmental assessment point sound intensity data Figure 3 Factory 1 sound intensity figure out station (a) is on the left side of the measuring point area(b) is the lateral area measuring point(c) is a point on the right side area Figure 4 Measuring points 2 test area map Figure 5 Sound intensity measuring point 2 on the left side of the area chart Note: white column represents the sound intensity value is +, gray column represents the sound intensity value is Figure 6 Side area measuring point 2 sound intensity diagram Figure 7 Right area measuring point 2 sound intensity diagram The factory sound pressure level data Table 3 Qt all sound source within the octave of sound pressure level table Noise octave sound pressure level (dB) Noise source center frequency (Hz) 31.5 63 125 250 500
The technology of the sound pressure and sound intensity combination to identify environmental noise source can accurately identify the produce noise at boundary of the main sound source, which can be targeted to noise reduction of noise source, avoid troubleshooting each noise source noise reduction, which can save a lot of manpower, material and financial resources and has great application prospect.
Factory premises equipment generally more and azimuth, working time, there is uncertainty in the open, therefore, in order to obtain scientific, high accuracy data, you need to choose a reasonable period of time to ensure that all measuring devices may generate noise are in the open state, and recorded under the orientation of the device.
Figure 2 Factories and noise distribution factory out environmental assessment point pressure data.
Table 1 Environmental assessment point total sound pressure level table Noise source code 1 2 3 4 5 6 7 8 A-weighted sound pressure level (dB) 82 80 92 89 84 90 88 87 factory out environmental assessment point sound intensity data Figure 3 Factory 1 sound intensity figure out station (a) is on the left side of the measuring point area(b) is the lateral area measuring point(c) is a point on the right side area Figure 4 Measuring points 2 test area map Figure 5 Sound intensity measuring point 2 on the left side of the area chart Note: white column represents the sound intensity value is +, gray column represents the sound intensity value is Figure 6 Side area measuring point 2 sound intensity diagram Figure 7 Right area measuring point 2 sound intensity diagram The factory sound pressure level data Table 3 Qt all sound source within the octave of sound pressure level table Noise octave sound pressure level (dB) Noise source center frequency (Hz) 31.5 63 125 250 500
The technology of the sound pressure and sound intensity combination to identify environmental noise source can accurately identify the produce noise at boundary of the main sound source, which can be targeted to noise reduction of noise source, avoid troubleshooting each noise source noise reduction, which can save a lot of manpower, material and financial resources and has great application prospect.