Browse Titles - 3237 results
3D Numerical Simulation of the Hollow Square-Typed Polymer Based on Gas-Assisted Extrusion Method
(Switzerland: Trans Tech Publications, 2016), 9 page(s)
According to the properties of hollow square-typed polymer extrudate, the three dimensional numerical simulation of hollow square-typed polymer extrudate based on gas-assisted extrusion technology was performed by using finite element method. Meanwhile, four different gas-assisted modes imposed on the outer and in...
Sample
(Switzerland: Trans Tech Publications, 2016), 9 page(s)
Description
According to the properties of hollow square-typed polymer extrudate, the three dimensional numerical simulation of hollow square-typed polymer extrudate based on gas-assisted extrusion technology was performed by using finite element method. Meanwhile, four different gas-assisted modes imposed on the outer and inner wall of hollow square-type extrudate were considered. The extrudate swell ratios and field distributions, such as pressure drop, ve...
According to the properties of hollow square-typed polymer extrudate, the three dimensional numerical simulation of hollow square-typed polymer extrudate based on gas-assisted extrusion technology was performed by using finite element method. Meanwhile, four different gas-assisted modes imposed on the outer and inner wall of hollow square-type extrudate were considered. The extrudate swell ratios and field distributions, such as pressure drop, velocities and normal stresses of four different gas-assisted modes were obtained and compared with each other. Research results show that the extrudate swell ratios and field distributions of different gas-assisted modes are completely different. For the mode of gas-assisted on the single wall, the extrudate swell or shrink phenomena are large due to the non-symmetric properties of field distributions. For the no gas-assisted mode, although the physical field values are large, the extrudate swell ratio is not large due to the interaction role of both walls. For the mode of gas-assisted on both walls, the physical field values, such as pressure drop, normal velocities and stresses are all diminished, and the extrudate swell phenomenon was completely eliminated.
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Field of Study
Global Issues
Content Type
Periodical article
Date Published / Released
2016-07, 2016
Publisher
Trans Tech Publications
Topic / Theme
Engineering
Copyright Message
Copyright © 2016 Trans Tech Publications Ltd.
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3D Topography Analysis of Ball-End Milled H-13 Die Steel Surfaces Using Wavelet Decomposition Method
(Switzerland: Trans Tech Publications, 2016), 10 page(s)
Optical profiler is employed to measure the surface topography of H-13 die steel machined by ball end cutter. By using 2D discret wavelet decomposition, the topographies of different frequency bands are obtained and the influence of cutter posture on varying frequncy bands topography is studied. The results show t...
Sample
3D Topography Analysis of Ball-End Milled H-13 Die Steel Surfaces Using Wavelet Decomposition Method
(Switzerland: Trans Tech Publications, 2016), 10 page(s)
Description
Optical profiler is employed to measure the surface topography of H-13 die steel machined by ball end cutter. By using 2D discret wavelet decomposition, the topographies of different frequency bands are obtained and the influence of cutter posture on varying frequncy bands topography is studied. The results show that cutter posture has a great influence on the whole frequency band roughness. The changing trend of roughness is roughly the same und...
Optical profiler is employed to measure the surface topography of H-13 die steel machined by ball end cutter. By using 2D discret wavelet decomposition, the topographies of different frequency bands are obtained and the influence of cutter posture on varying frequncy bands topography is studied. The results show that cutter posture has a great influence on the whole frequency band roughness. The changing trend of roughness is roughly the same under different cutter postures which increase firstly then decrease with the decrease in frequency. A surface with a small high frequency roughness may have a large median frequency roughness.
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Field of Study
Global Issues
Content Type
Periodical article
Date Published / Released
2016-05, 2016
Publisher
Trans Tech Publications
Topic / Theme
Engineering
Copyright Message
Copyright © 2016 Trans Tech Publications Ltd.
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Abnormal Grain Growth on the Surface of Cold-Rolled AA1235 Aluminum Plate during the Annealing Process
(Switzerland: Trans Tech Publications, 2017), 12 page(s)
AA1235 aluminum alloys were twin roll cast into a 7.0 mm-thick billet and further rolled into a plate with 70% reduction, followed by annealing at 500 C for 8 h. Abnormal grains were found to be formed on the plate bottom surface. SEM, EBSD, and micro X-ray diffraction were used to analyze the mechanism underlying...
Sample
(Switzerland: Trans Tech Publications, 2017), 12 page(s)
Description
AA1235 aluminum alloys were twin roll cast into a 7.0 mm-thick billet and further rolled into a plate with 70% reduction, followed by annealing at 500 C for 8 h. Abnormal grains were found to be formed on the plate bottom surface. SEM, EBSD, and micro X-ray diffraction were used to analyze the mechanism underlying the abnormal growth of these grains. Results showed that the {100} >001001
AA1235 aluminum alloys were twin roll cast into a 7.0 mm-thick billet and further rolled into a plate with 70% reduction, followed by annealing at 500 C for 8 h. Abnormal grains were found to be formed on the plate bottom surface. SEM, EBSD, and micro X-ray diffraction were used to analyze the mechanism underlying the abnormal growth of these grains. Results showed that the {100} >001< texture was formed in the surrounding normal grains adjacent to the abnormal grain. The orientation angle between the abnormal grain and its adjacent normal grains was 45°. The {100} >001< texture formed during rolling and annealing accelerated abnormal grain growth. The partially dissolved Fe precipitates were heterogeneously distributed in the plate bottom heterogeneously, which also mainly explained abnormal grain growth.
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Field of Study
Global Issues
Content Type
Periodical article
Date Published / Released
2017-06, 2017
Publisher
Trans Tech Publications
Topic / Theme
Engineering
Copyright Message
Copyright © 2017 Trans Tech Publications Ltd.
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The Abolitionists
written by Jordan Smith, fl. 2000 and Liliana Segura, fl. 2014 (New York, NY: Intercept (News website), 2019),
Source: theintercept.com
Source: theintercept.com
Sample
written by Jordan Smith, fl. 2000 and Liliana Segura, fl. 2014 (New York, NY: Intercept (News website), 2019),
Source: theintercept.com
Source: theintercept.com
Field of Study
Global Issues
Content Type
Periodical article
Author / Creator
Jordan Smith, fl. 2000, Liliana Segura, fl. 2014
Date Published / Released
2019-12-03, 2019
Publisher
Intercept (News website)
Topic / Theme
Death Penalty, Abolitionists, Race discrimination, Prisoners, Executions, Capital punishment, State and provincial laws, History, Sociology, Politics & Policy, Law, Prison Policy, Conditions of Confinement, 21st Century in World History (2001– )
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About Formability of Ultra-Fine Grained Metallic Materials
(Switzerland: Trans Tech Publications, 2016), 9 page(s)
Ultra-fine grained (UFG) and nanostructured metallic materials obtained via severe plastic deformation typically show very high mechanical strength but low tensile ductility, which dramatically limits their practical utility. Significant efforts were made to improve uniaxial tensile ductility of ultra-fine grained...
Sample
(Switzerland: Trans Tech Publications, 2016), 9 page(s)
Description
Ultra-fine grained (UFG) and nanostructured metallic materials obtained via severe plastic deformation typically show very high mechanical strength but low tensile ductility, which dramatically limits their practical utility. Significant efforts were made to improve uniaxial tensile ductility of ultra-fine grained and nanostructured metallic materials. The developed strategies can be divided into two main groups. (1) The 'mechanical' strategies e...
Ultra-fine grained (UFG) and nanostructured metallic materials obtained via severe plastic deformation typically show very high mechanical strength but low tensile ductility, which dramatically limits their practical utility. Significant efforts were made to improve uniaxial tensile ductility of ultra-fine grained and nanostructured metallic materials. The developed strategies can be divided into two main groups. (1) The 'mechanical' strategies employ the mechanical characteristics of these materials, such as their work hardening ability and/or strain rate sensitivity. These mechanical characteristics can be varied via changing testing parameters, such as temperature and/or strain rate. (2) The 'microstructural' strategies are based on idea of intelligent microstructural design to suppress necking at early stages of plastic deformation thus improving ductility. However, not much attention was paid to the fact, that in metallforming operations, metallic materials are not deformed uniaxially, but have to undergo deformation under complex strain paths. This work aims to demonstrate that despite UFG metallic materials have low tensile ductility, they can show enhanced formability during plastic deformation in complex stress state (such as formability under biaxial stretch, which is sufficient for metalforming operations.
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Field of Study
Global Issues
Content Type
Periodical article
Date Published / Released
2016-01, 2016
Publisher
Trans Tech Publications
Topic / Theme
Engineering
Copyright Message
Copyright © 2016 Trans Tech Publications Ltd.
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About the Possibility of Applying Coloured Soil-Cement in Making Road Pavement Layers
(Switzerland: Trans Tech Publications, 2016), 9 page(s)
The issue of the urban environment decoration has continuously been the task of urban architecture authority and it is quite successfully performed. Adding pigments, using coloured filler in the content of bitumen-concrete mixtures or applying multi-coloured paving stones and mosaic rigid concrete pavements provid...
Sample
(Switzerland: Trans Tech Publications, 2016), 9 page(s)
Description
The issue of the urban environment decoration has continuously been the task of urban architecture authority and it is quite successfully performed. Adding pigments, using coloured filler in the content of bitumen-concrete mixtures or applying multi-coloured paving stones and mosaic rigid concrete pavements provide additional positive impression in the perception of intra-buildings space and modern urban landscape. The use of local materials with...
The issue of the urban environment decoration has continuously been the task of urban architecture authority and it is quite successfully performed. Adding pigments, using coloured filler in the content of bitumen-concrete mixtures or applying multi-coloured paving stones and mosaic rigid concrete pavements provide additional positive impression in the perception of intra-buildings space and modern urban landscape. The use of local materials with adding pigments for the design of residential areas can be extremely important for local communities.In order to test soil-cement mixtures with added colour pigment for road pavements on the basis of construction laboratory at Lutsk NTU, a series of experiments has been planned to answer the question of the pigment amount impact on the physical and mechanical properties of the materials and finding the best ratios for them.
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Field of Study
Global Issues
Content Type
Periodical article
Date Published / Released
2016-09, 2016
Publisher
Trans Tech Publications
Topic / Theme
Engineering
Copyright Message
Copyright © 2016 Trans Tech Publications Ltd.
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Abstract: Assessment of the Environmental Effects of Constructing the Three Gorge Project on the Yangtze River
written by Jim LaBounty, fl. 1986, in Records of the Bureau of Reclamation, 1889 - 2008 (RG115). Case Files on Yangtze Gorge and Three Gorges Dam, China, 1943 - 1996 (NRG-115-05-088), of United States. National Archives and Records Administration. Federal Records (1984), Box 38, Folder 233023-0: Congressional Inquiries and Requests for Information, Folder 2 (Netherlands: Elsevier, 1984), 1 page(s)
Sample
written by Jim LaBounty, fl. 1986, in Records of the Bureau of Reclamation, 1889 - 2008 (RG115). Case Files on Yangtze Gorge and Three Gorges Dam, China, 1943 - 1996 (NRG-115-05-088), of United States. National Archives and Records Administration. Federal Records (1984), Box 38, Folder 233023-0: Congressional Inquiries and Requests for Information, Folder 2 (Netherlands: Elsevier, 1984), 1 page(s)
Date Written / Recorded
1984
Field of Study
Environmental Studies
Content Type
Periodical article
Author / Creator
Jim LaBounty, fl. 1986
Date Published / Released
1984
Publisher
Elsevier
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Accounting Model of CO2 and its Application in Integrated Iron and Steel Enterprises
(Switzerland: Trans Tech Publications, 2015), 15 page(s)
Integrated iron and steel enterprises is taken as the research object. Under the guidance of GHG Protocol standards for carbon emissions, the carbon dioxide accounting models on the process as a whole boundary are established, in which, the carbon emissions inventory is divided into three levels and the input data...
Sample
(Switzerland: Trans Tech Publications, 2015), 15 page(s)
Description
Integrated iron and steel enterprises is taken as the research object. Under the guidance of GHG Protocol standards for carbon emissions, the carbon dioxide accounting models on the process as a whole boundary are established, in which, the carbon emissions inventory is divided into three levels and the input data consists of CO2 emission coefficient and activity factor level data. The process model is the accounting model that the carbon emissio...
Integrated iron and steel enterprises is taken as the research object. Under the guidance of GHG Protocol standards for carbon emissions, the carbon dioxide accounting models on the process as a whole boundary are established, in which, the carbon emissions inventory is divided into three levels and the input data consists of CO2 emission coefficient and activity factor level data. The process model is the accounting model that the carbon emission is obtained through the balance of carbon input and carbon output outside the process boundary under the condition of considering the enterprise circulation. This article also researched one integrated iron and steel enterprise as a case. The results show that the model can quantify the emissions of different processes, provide basic value for the enterprise reduction, Identify major carbon source, identify the influence on carbon emissions by the changes of fuel structure, the structure of the process parameters and outsourcing by-product internal circulation. Therefore the model results can be used in the carbon emissions of enterprise internal assessment and decision-making.
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Field of Study
Global Issues
Content Type
Periodical article
Date Published / Released
2015-03, 2015
Publisher
Trans Tech Publications
Topic / Theme
Engineering
Copyright Message
Copyright © 2015 Trans Tech Publications Ltd.
×
Accuracy and Material Properties in Incremental Forming for a Multi-Step Expanding Approach
(Switzerland: Trans Tech Publications, 2015), 10 page(s)
In incremental sheet forming the material properties change dependent on the wall angle. In addition to sheet thinning, material hardening can be observed and for stainless steel the formation of strain induced martensite has been reported. These process characteristics have been extensively examined for the formi...
Sample
(Switzerland: Trans Tech Publications, 2015), 10 page(s)
Description
In incremental sheet forming the material properties change dependent on the wall angle. In addition to sheet thinning, material hardening can be observed and for stainless steel the formation of strain induced martensite has been reported. These process characteristics have been extensively examined for the forming of parts in one step. In this study, a first investigation is made to control the material properties independent on the wall angle...
In incremental sheet forming the material properties change dependent on the wall angle. In addition to sheet thinning, material hardening can be observed and for stainless steel the formation of strain induced martensite has been reported. These process characteristics have been extensively examined for the forming of parts in one step. In this study, a first investigation is made to control the material properties independent on the wall angle by a multi-step expanding approach. For this, in the first step a steep wall angle is formed and in the following steps this region is transformed to a shallow wall angle, keeping the material properties. To demonstrate and verify this new approach a small cone frustum with a wall angle of 60° was formed as a preform. This cone frustum was repeatedly expanded in steps of 2° to get finally a cone frustum with 30° wall angle. The stepwise expanding causes a considerably growing of the shape in depth direction, especially at the preformed area. By a heuristic approach the geometric accuracy of the final cone was optimized. The microhardness measurement of the formed cones shows that the final cone frustum has a region, where the material properties are similar to the first formed 60° wall angle. By this new approach the possibility to influence the material properties of the final part purely by tool path is demonstrated. In particular it is possible to form regions with shallow wall angles that have the material properties of regions with steep wall angles.
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Field of Study
Global Issues
Content Type
Periodical article
Date Published / Released
2015-03, 2015
Publisher
Trans Tech Publications
Topic / Theme
Engineering
Copyright Message
Copyright © 2015 Trans Tech Publications Ltd.
×
Accurate and Traceable Calibration of the Stiffness of Various AFM Cantilevers
(Switzerland: Trans Tech Publications, 2015), 10 page(s)
Atomic force microscope (AFM) is widely used to measure nanoforce in the analysis of nanomechanical and biomechanical properties. As the critical factor in the nanoforce measurement, the stiffness of the AFM cantilever must be determined properly. In this paper, an accurate and SI-traceable calibration method is p...
Sample
(Switzerland: Trans Tech Publications, 2015), 10 page(s)
Description
Atomic force microscope (AFM) is widely used to measure nanoforce in the analysis of nanomechanical and biomechanical properties. As the critical factor in the nanoforce measurement, the stiffness of the AFM cantilever must be determined properly. In this paper, an accurate and SI-traceable calibration method is presented to obtain the stiffness of the AFM cantilever in the normal direction. The calibration system consists of a homemade AFM head...
Atomic force microscope (AFM) is widely used to measure nanoforce in the analysis of nanomechanical and biomechanical properties. As the critical factor in the nanoforce measurement, the stiffness of the AFM cantilever must be determined properly. In this paper, an accurate and SI-traceable calibration method is presented to obtain the stiffness of the AFM cantilever in the normal direction. The calibration system consists of a homemade AFM head and an ultra-precision electromagnetic balance. The calibration is based on the Hooke's law i.e. the stiffness is equal to the force divided by the deflection of the cantilever. With this system, three kinds of cantilevers were calibrated. The relative standard deviation is better than 1%. The results of these experiments showed good accuracy and repeatability.
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Field of Study
Global Issues
Content Type
Periodical article
Date Published / Released
2015-05, 2015
Publisher
Trans Tech Publications
Topic / Theme
Engineering
Copyright Message
Copyright © 2015 Trans Tech Publications Ltd.
×