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Online since: October 2013
Authors: Ling Lu, Xiu Hai Yin
The CFRD dam deformation and rupture panels result in a large number of leakages which affect the normal operation of the projects.
The shearing stress is in proportion to the relative displacement, the stiffness coefficient is the scale factor.
According to the reservoir rock physical mechanics from the rock fill test results, the suggested values of rock mechanical parameters in the Mohr-Coulomb model are shown in Table 1.
The concrete panel construction requirements must be strictly ensure the quality, as far as possible using some special properties of the concrete to improve its tensile strength at the same time.
The shearing stress is in proportion to the relative displacement, the stiffness coefficient is the scale factor.
According to the reservoir rock physical mechanics from the rock fill test results, the suggested values of rock mechanical parameters in the Mohr-Coulomb model are shown in Table 1.
The concrete panel construction requirements must be strictly ensure the quality, as far as possible using some special properties of the concrete to improve its tensile strength at the same time.
Online since: February 2013
Authors: Ning Ning Zhan, Wen Xiu Zhao, Zhen Zhong Fan, Ji Gang Wang, Qing Wang Liu, Chun Yu Liu
Whether the high angle holes can develop efficiently, cementing quality is a key factor, which put forward higher requirements of the slurry system and the cementing process measures.
G302 is a polymer-based materials, it can reduce the permeability of the cement matrix and improve the gelling properties of the slurry.
F17D is a crystal expansion material, it mainly rely on crystalline expansion pressure, make external work by change the chemical energy into mechanical force, resulting in volume expansion of the cement stone.
If adding too much dispersing agent into the slurry in order to reach the turbulent flow replacement, the stability of the cement slurry will deteriorate, a water ring will form in the cement sheath and the interface between strata and cement ring, consequently affect the sealing of the formation.
G302 is a polymer-based materials, it can reduce the permeability of the cement matrix and improve the gelling properties of the slurry.
F17D is a crystal expansion material, it mainly rely on crystalline expansion pressure, make external work by change the chemical energy into mechanical force, resulting in volume expansion of the cement stone.
If adding too much dispersing agent into the slurry in order to reach the turbulent flow replacement, the stability of the cement slurry will deteriorate, a water ring will form in the cement sheath and the interface between strata and cement ring, consequently affect the sealing of the formation.
Online since: May 2015
Authors: Abdullah Yassin, Chong Yaw Teo
Yassinb
Mechanical and Manufacturing Engineering Department, Faculty of Engineering, University Malaysia Sarawak, 94300 Kota Samarahan, Sarawak, Malaysia.
Operators on the shop floor may be affected by such application of cutting fluids, resulting in skin and respiratory health problems [4].
To encounter this problem, increasing researches have been carried out on the usage of vegetable based oil in MQL resulting in reduction of health hazard factor [13].
The effectiveness of MQL in reducing cutting temperature and wear is mostly affected by the ability of the fluids penetrating the cutting zone and the time period it stays in the cutting zone to serve its cooling and lubricating effects.
Demirbas, Relationships derived from physical properties of vegetable oil and biodiesel fuels, Fuel. 87 (2008) 1743-1748
Operators on the shop floor may be affected by such application of cutting fluids, resulting in skin and respiratory health problems [4].
To encounter this problem, increasing researches have been carried out on the usage of vegetable based oil in MQL resulting in reduction of health hazard factor [13].
The effectiveness of MQL in reducing cutting temperature and wear is mostly affected by the ability of the fluids penetrating the cutting zone and the time period it stays in the cutting zone to serve its cooling and lubricating effects.
Demirbas, Relationships derived from physical properties of vegetable oil and biodiesel fuels, Fuel. 87 (2008) 1743-1748
The Evolution of Texture and Deformation Anisotropy at an Equal Channel Extruded Aluminum 1050 Alloy
Online since: May 2014
Authors: Andrea Madeira Kliauga, W.R. Sussai, R.E. Bolmaro
To date, many studies have been dedicated to investigate the development of crystallographic textures in ECAP, due to its significance in understanding the deformation mechanisms and its influence on the microstructure evolution as well as mechanical properties of the processed materials [1-5].
The grain refinement during the ECAP process is affected by accumulative strain and the interaction of shearing plane with crystal structure and deformation texture.
Table 1: Main ideal orientations along the shear fibers and usual rolling orientations given by the Miller indices {h k l} and Euler angles for a ODF section of j2= 45o
Notation
Texture component
F
j1
H
{100} <110>
0
0; 90; 180; 270
Shear Components
A
{111} <110>
35.26
0;180
B
{112} <110>
54.7
0;60;120;180;240;300
C
{001} <001>
90
0;180
A*
{111} <112>
90
54.74; 125.26; 234.74;
Cube
{100} <001>
0
45; 135; 225; 315
Rolling Components
Copper
{112} <111>
35
90; 270
Goss
{110} <001>
90
90; 270
Brass
{110} <112>
90
55; 125; 235; 305
Texture development introduces crystallographic anisotropy on the macroscale which, in turn, affects the deep-drawability.
Texture intensity {111} pole figure Lankford factor Normal anisotropy Planar anisotropy Sample (times random) 0o 45o 90o rm Dr C 4xA 25,0 0,345 0,339 0,043 0,266 0,14 C 4xAy 3,0 0,443 0,507 0,275 0,433 0,15 C 4xBc 2,8 0,271 0,341 0,257 0,302 0,08 HR 4xA 2,8 0,543 0,418 0,411 0,447 0,06 HR 4xAy 4,0 0,284 0,393 0,187 0,314 0,16 Summary The behaviour of the caster and hot rolled samples was very simmilar, but with differences in the texture intensities.
The grain refinement during the ECAP process is affected by accumulative strain and the interaction of shearing plane with crystal structure and deformation texture.
Table 1: Main ideal orientations along the shear fibers and usual rolling orientations given by the Miller indices {h k l}
Texture intensity {111} pole figure Lankford factor Normal anisotropy Planar anisotropy Sample (times random) 0o 45o 90o rm Dr C 4xA 25,0 0,345 0,339 0,043 0,266 0,14 C 4xAy 3,0 0,443 0,507 0,275 0,433 0,15 C 4xBc 2,8 0,271 0,341 0,257 0,302 0,08 HR 4xA 2,8 0,543 0,418 0,411 0,447 0,06 HR 4xAy 4,0 0,284 0,393 0,187 0,314 0,16 Summary The behaviour of the caster and hot rolled samples was very simmilar, but with differences in the texture intensities.
Online since: June 2007
Authors: O.S. Fakolujo, S.O. Jimoh, B.S.O. Ighalo
Ighalo
3,c
1
Mechanical Engineering Department, Yaba College of Technology, Yaba
Lagos State, Nigeria
2,3
Materials and Production Engineering, Ambrose Alli University,
Ekpoma, Edo State, Nigeria,
a
e-mail: samfakolujo_1@yahoo.com, be-mail: smailajimoh2001/2002@yahoo.com, cemail:ighalobsoighalo@yahoo.com
Keywords: Fuels, Used engine oil, kerosene, combustion, foundry
Abstract: This study presents the experimental results of using admixture of used engine oil and
kerosene as an alternative fuel in foundry shops.
Therefore for a liquid fuel to be effective as an industrial fuel its quality must be assessed and this is achieved by measuring the most diverse physiochemical and service properties reflecting its suitability and effectiveness [1].
In oil firing, the characteristics of an oil flame are affected mainly by the composition of the fuel and the rate at which fuel and air are mixed and subsequently burned in the combustion zone.
Another factor that affects combustion of fuel is the pour point which is the loss of fluidity of fuel [6].
Therefore for a liquid fuel to be effective as an industrial fuel its quality must be assessed and this is achieved by measuring the most diverse physiochemical and service properties reflecting its suitability and effectiveness [1].
In oil firing, the characteristics of an oil flame are affected mainly by the composition of the fuel and the rate at which fuel and air are mixed and subsequently burned in the combustion zone.
Another factor that affects combustion of fuel is the pour point which is the loss of fluidity of fuel [6].
Online since: August 2012
Authors: F.J.C. Braga, W. de Rossi, Amanda Abati Aguiar, R.E. Samad, N.D. Vieira, Nelson B. Lima
When compared to metallic materials, a problematic aspect of ceramic materials is their low mechanical strength and fracture toughness [3].
The adhesion of hydroxylapatite, as well as their morphology depends on the surface properties of materials.
Depending on the material and process parameters microstructures changes may occur as a grain refinement, phase transformations, alloy formation and a mixture of composite materials on the surface without actually affecting the bulk of the material.
The value of w0 is obtained from the Equation 3 below [1], where M2 is the beam quality factor, l is the wavelength of the laser, f is the focal length of the focusing lens, f and ffocus are the beam diameter behind the lens and at the focus respectively.
The adhesion of hydroxylapatite, as well as their morphology depends on the surface properties of materials.
Depending on the material and process parameters microstructures changes may occur as a grain refinement, phase transformations, alloy formation and a mixture of composite materials on the surface without actually affecting the bulk of the material.
The value of w0 is obtained from the Equation 3 below [1], where M2 is the beam quality factor, l is the wavelength of the laser, f is the focal length of the focusing lens, f and ffocus are the beam diameter behind the lens and at the focus respectively.
Online since: September 2014
Authors: Grzegorz Samołyk
Introduction
One of the present trends in mechanical engineering is a wider use of parts with reduced weight and high strength properties; an example of such parts being hollow parts.
Parts with the above-mentioned properties can be produced in two ways.
The variations of the force depend on both geometrical properties of the upper region of the workpiece and changes in the upper die-material contact surface (as can be seen from Fig. 6).
The amplitude-like character of the torque distribution results from the properties of numerical modelling, i.e. changes in the material-tools contact surface.
The temperature drops to 400°C, which means that the effect of temperature on properties of the tools should be investigated in further research works.
Parts with the above-mentioned properties can be produced in two ways.
The variations of the force depend on both geometrical properties of the upper region of the workpiece and changes in the upper die-material contact surface (as can be seen from Fig. 6).
The amplitude-like character of the torque distribution results from the properties of numerical modelling, i.e. changes in the material-tools contact surface.
The temperature drops to 400°C, which means that the effect of temperature on properties of the tools should be investigated in further research works.
Online since: February 2019
Authors: O.S. Es-Said, Fahad Alzubi, Kelly Tovalin, Mark Timko, Yong Jun Li, Ray Toal
Analyses of the results were performed in order to (1) compare large vs. small grain behavior at fixed stresses, and (2) understand and quantify fatigue properties in relation to varying stress.
Table 6 shows the cycles to failure for each test, along with computed properties such as the average number of cycles to failure, the sample standard deviation for the test data set, and the Weibull slope [31].
Table 6: Cycles to failure for each test, along with computed properties such as the average number of cycles to failure.
Effects of alloying elements on properties of aluminum alloys [SubsTech].
Aluminum: properties and physical metallurgy.
Table 6 shows the cycles to failure for each test, along with computed properties such as the average number of cycles to failure, the sample standard deviation for the test data set, and the Weibull slope [31].
Table 6: Cycles to failure for each test, along with computed properties such as the average number of cycles to failure.
Effects of alloying elements on properties of aluminum alloys [SubsTech].
Aluminum: properties and physical metallurgy.
Online since: February 2025
Authors: Kabo Benedict Jongman, Girum Ayalneh, Getachew Dagnew Gebreeyessus
Due to the mentioned risk exposure to contamination, the soil and water systems get affected.
Clay materials, are known for their abundant availability and unique physicochemical properties, have been explored as components of MFCs.
Therefore results show that there was a higher growth in factor 10-2 and 10-3 which makes a lot of sense because the purpose of serial dilution is to reduce the concentration of micro-organisms so at these dilution factors there was still a very high concentration of microorganisms from the inoculum which is signified by high microbial growth on the plates.
As the dilution factor increases the microbial concentration decreases, which was justified by these results because high dilution factors resulted in low to no microbial growth.
Throughout the study, unexpected activity observed in the control, which was attributed to the possibility of, influence both biotic and abiotic factors, such as untreated clay during fabrication and the inherent electrochemical properties of carbon cloths as electrodes.
Clay materials, are known for their abundant availability and unique physicochemical properties, have been explored as components of MFCs.
Therefore results show that there was a higher growth in factor 10-2 and 10-3 which makes a lot of sense because the purpose of serial dilution is to reduce the concentration of micro-organisms so at these dilution factors there was still a very high concentration of microorganisms from the inoculum which is signified by high microbial growth on the plates.
As the dilution factor increases the microbial concentration decreases, which was justified by these results because high dilution factors resulted in low to no microbial growth.
Throughout the study, unexpected activity observed in the control, which was attributed to the possibility of, influence both biotic and abiotic factors, such as untreated clay during fabrication and the inherent electrochemical properties of carbon cloths as electrodes.
Online since: March 2010
Authors: Luigi Tricarico, Donato Sorgente
Post-forming characteristics are mainly affected by thickness variations along
the sheet.
All of these techniques require additional operations (i.e. machining, chemical milling or forming operations such as rotary forming) for the preparation of the blank but they can still be considered convenient for improving the mechanical properties of the product especially in a high-cost and low-volume manufacturing process.
Inverse techniques As seen in previous sections, FE simulations are usually performed to calculate displacements, strains, stresses for given external loads, initial and boundary conditions, geometrical configuration and material properties.
Some other, like material properties and friction coefficients, are difficult to measure (or calculate) but have, like other parameters, a huge role in the quality of numerical results.
The basis of the inverse approach is to consider material properties and/or friction coefficients (or other not well-known parameters) as new unknown parameters and to add experimental results as new input data for the simulation [48].
All of these techniques require additional operations (i.e. machining, chemical milling or forming operations such as rotary forming) for the preparation of the blank but they can still be considered convenient for improving the mechanical properties of the product especially in a high-cost and low-volume manufacturing process.
Inverse techniques As seen in previous sections, FE simulations are usually performed to calculate displacements, strains, stresses for given external loads, initial and boundary conditions, geometrical configuration and material properties.
Some other, like material properties and friction coefficients, are difficult to measure (or calculate) but have, like other parameters, a huge role in the quality of numerical results.
The basis of the inverse approach is to consider material properties and/or friction coefficients (or other not well-known parameters) as new unknown parameters and to add experimental results as new input data for the simulation [48].