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Online since: January 2014
Authors: Alžbeta Sapietová, Richard Petrech, Matej Petrovic
An analytical calculation of dynamic forces in mechanism was solved by the method of mass reduction and force parameters [3].
The method of the mass reduction and force parameters is based on the balance of the flow of mass, momentum, and energy of multi-body systems.
Reduction of force effects is realized through the equal the power of work forces and reduced system performance of work forces of the initial multi-body system, which neglects gravitation forces.
Pressure [MPa] a) b) Fig. 9 a) Equivalent (von-Mises) stress, b) Curve of equivalent (von-Mises) stress Sumary The outputs of the simulations contain a large amount of data on individual parts of the virtual prototype (speeds, accelerations, position, interactions of the force, etc.).
The method of the mass reduction and force parameters is based on the balance of the flow of mass, momentum, and energy of multi-body systems.
Reduction of force effects is realized through the equal the power of work forces and reduced system performance of work forces of the initial multi-body system, which neglects gravitation forces.
Pressure [MPa] a) b) Fig. 9 a) Equivalent (von-Mises) stress, b) Curve of equivalent (von-Mises) stress Sumary The outputs of the simulations contain a large amount of data on individual parts of the virtual prototype (speeds, accelerations, position, interactions of the force, etc.).
Online since: December 2012
Authors: Yousif A. Mansoor, Zhi Qiang Zhang
The strength without any reduction
B.
The small reduction in strength.
The width of crack is more 0.35 mm The strength is more reduction.
The process of the diagnosis of the damages is applied as a menu-driven and question-and-answer, the process is composed of all steps as abstracted in the data flow diagram in the Figure 3.
The small reduction in strength.
The width of crack is more 0.35 mm The strength is more reduction.
The process of the diagnosis of the damages is applied as a menu-driven and question-and-answer, the process is composed of all steps as abstracted in the data flow diagram in the Figure 3.
Online since: December 2014
Authors: Kai Ming Wang, Xiao Qi Li, Shou Shan Gao, Wei Liang Huan, Hong Bao Jia
The following methods are used to prepare nitride: direct nitrizing method, carbon thermal reduction method, benzene thermal method[5, high temperature self-spreading method[6], gas phase method, and aminolysis method etc.[7], while direct nitrizing method including high energy ball milling[8] and mechanical activation methods[9].
But if nitrizing is carried under normal pressure, reduction process using tubular furnace, and materials putting on ceramic plate, the raw material layer cannot be thicker (less than 5 millimeter), otherwise the temperature cannot be lowered, time cannot be shorten, the nitrizing will be incomplete, and the grain sizes can be larger.
Mixing and contacting of reacting gas (ammonia and hydrogen) with nanopowder are improved greatly, thus resultant nanograin size reduction becomes possible.
The data is in agreement with gas-solid reaction mechanism analysed by Szekely [12] and Qingyin Ge [13], and proves that system pressure has large effects on aminolysis temperature and pressure.
But if nitrizing is carried under normal pressure, reduction process using tubular furnace, and materials putting on ceramic plate, the raw material layer cannot be thicker (less than 5 millimeter), otherwise the temperature cannot be lowered, time cannot be shorten, the nitrizing will be incomplete, and the grain sizes can be larger.
Mixing and contacting of reacting gas (ammonia and hydrogen) with nanopowder are improved greatly, thus resultant nanograin size reduction becomes possible.
The data is in agreement with gas-solid reaction mechanism analysed by Szekely [12] and Qingyin Ge [13], and proves that system pressure has large effects on aminolysis temperature and pressure.
Online since: November 2015
Authors: Bo Wei Chen, Ming Jiang Zhang, Wen Yan Liu, Chun Yu Meng, Xing Yu Liu, Jian Kang Wen
The potential for Fe(III) reduction seems to be widespread among acidophilic heterotrophs.
The utilization of Fe(III) and reduction of schwertmannite Fe(III) and reduce schwertmannite by genus Alicyclobacillus was reported previously[8].
Our research also finds that when Alicyclobacillus was present, the formation of jarosite was diminished in chalcopyrite bioleaching at high temperature (unpublished data).
Considering the Fe(III) reduction ability, it seems under high temperature, that the presence of Alicyclobacillus may: a. help to reduce jarosite; b. help to reduce Fe(III) coupled with sulphur oxidation.
The utilization of Fe(III) and reduction of schwertmannite Fe(III) and reduce schwertmannite by genus Alicyclobacillus was reported previously[8].
Our research also finds that when Alicyclobacillus was present, the formation of jarosite was diminished in chalcopyrite bioleaching at high temperature (unpublished data).
Considering the Fe(III) reduction ability, it seems under high temperature, that the presence of Alicyclobacillus may: a. help to reduce jarosite; b. help to reduce Fe(III) coupled with sulphur oxidation.
Online since: April 2010
Authors: Yali Wang, Lin Jun Wang, Ming Sheng Ma, Wen Ni, Yun Sheng Feng
The recycling of industrial wastes in glass ceramic production
is an effective way for the volume reduction of the waste [6,7].
The smelting reduction process was carried out to remove FeO before glass preparation.
The slag which obtained by reducing most of FeO and heavy metals by the fusion reduction process was termed as secondary slag.
In this experiment, the DSC measurements were carried out with heating rate at 5, 10, 15, 20 k/min the data of Tp was listed in Table 3.
The smelting reduction process was carried out to remove FeO before glass preparation.
The slag which obtained by reducing most of FeO and heavy metals by the fusion reduction process was termed as secondary slag.
In this experiment, the DSC measurements were carried out with heating rate at 5, 10, 15, 20 k/min the data of Tp was listed in Table 3.
Properties of Al-Si-Fe-Cu-Mg Alloy PM Composites Obtained by Closed - Die Forging and Heat Treatment
Online since: January 2010
Authors: Stefan Szczepanik, Marek Wojtaszek
Research aiming at the
development of these materials is primarily focused on gathering experimental data necessary to
design their chemical composition, structure and properties [1, 2, 3], and inventing a method for
their production and forming in order to obtain semi-finished and finished products [1, 4, 5].
Compression strength of heat treated materials obtained by closed die forging of: a - cold consolidated PM preforms, b - hot consolidated PM performs, C - hot consolidation, HT- heat treatment, F- closed-die forging. 7,31 7,30 7,31 7,64 7,95 8,06 7,92 8,96 0 3 6 9 12 reduction of height, % C C+HT C+F C+F+HT Fig. 7.
Critical reduction of height during compression of materials obtained by hot consolidation of powders, closed die - forging and additional heat treatment.
Al Al17 Conclusions High density composite materials from the aluminium RAl-1 and its alloy Al17Si5Fe3Cu1.1Mg0.6Zr, ranging in composition in 20 wt.% steps, were produced using Powder Metallurgy and subsequent plastic work and heat treatment, The increase of alloy content leads to very good mechanical properties in bending and compression: increase in bend strength from 400 to 540 MPa, compression strengths from 415 to 744 MPa, hardness from 32 to 203HB, and a reduction in the critical height during compression.
Compression strength of heat treated materials obtained by closed die forging of: a - cold consolidated PM preforms, b - hot consolidated PM performs, C - hot consolidation, HT- heat treatment, F- closed-die forging. 7,31 7,30 7,31 7,64 7,95 8,06 7,92 8,96 0 3 6 9 12 reduction of height, % C C+HT C+F C+F+HT Fig. 7.
Critical reduction of height during compression of materials obtained by hot consolidation of powders, closed die - forging and additional heat treatment.
Al Al17 Conclusions High density composite materials from the aluminium RAl-1 and its alloy Al17Si5Fe3Cu1.1Mg0.6Zr, ranging in composition in 20 wt.% steps, were produced using Powder Metallurgy and subsequent plastic work and heat treatment, The increase of alloy content leads to very good mechanical properties in bending and compression: increase in bend strength from 400 to 540 MPa, compression strengths from 415 to 744 MPa, hardness from 32 to 203HB, and a reduction in the critical height during compression.
Online since: November 2012
Authors: Xue Wen Lei, Cong Lin, Qing Shan Meng, Rong Fang Zhou
(4)
where, is reduction factor of permeability coefficient, which expresses the effect of permeability coefficient on saturation. , are the same as above.
Fig.1 and Fig.2 respectively describes the relationship between reduction coefficient and saturation and the relationship between matric suction and saturation in this paper.
Fig. 1 Relationship between reduction coefficient Fig. 2 Relationship between matric suction and saturation and saturation The boundary conditions of rainfall infiltration.
The boundary conditions of rainfall infiltration changed with the time are expressed by the tabular amplitude curve, and the related data is shown in Table 2.
Fig.1 and Fig.2 respectively describes the relationship between reduction coefficient and saturation and the relationship between matric suction and saturation in this paper.
Fig. 1 Relationship between reduction coefficient Fig. 2 Relationship between matric suction and saturation and saturation The boundary conditions of rainfall infiltration.
The boundary conditions of rainfall infiltration changed with the time are expressed by the tabular amplitude curve, and the related data is shown in Table 2.
Online since: December 2013
Authors: Marek Tkocz, Franciszek Grosman
This approach offers important benefits such as improved structural stiffness of an aircraft, reduction of labor, time and tooling costs required for assembly operations, reduction of inventory etc. [1].
A schematic diagram of the device for incremental forming equipped with sensors of the control and data acquisition system: 1 - punch, 2 - pressure plate, 3 - working rolls, 4 - segmental punch, 5 - press table, 6 - die, 7 - workpiece, 8 - punch retainer Fig.2.
Division of a punch into segments and pressing them by moving rolls causes temporary load exertion only on a small fragment of the workpiece surface, enabling significant reduction of the required press load.
A schematic diagram of the device for incremental forming equipped with sensors of the control and data acquisition system: 1 - punch, 2 - pressure plate, 3 - working rolls, 4 - segmental punch, 5 - press table, 6 - die, 7 - workpiece, 8 - punch retainer Fig.2.
Division of a punch into segments and pressing them by moving rolls causes temporary load exertion only on a small fragment of the workpiece surface, enabling significant reduction of the required press load.
Online since: December 2010
Authors: Shun Bo Zhao, Li Xin Liu, Li Sun, Su Yang, Na Liang
With long-term exposure to air conditions, the problems such as falling off and many kinds of cracks caused by environmental factors often turned up on the external surface, which resulted in the directly exposing to air conditions and the aging phenomenon of polystyrene panel, furthermore, caused the reduction of the insulating properties.
The largest relative differential of cubic and axial compressive strengths of all concrete are 9.6 % and 8.8 %, which are in the range of allowable error of statistical calculation for test data.
There is positive effect of the lower elastic modulus on the reduction of tensile thermal stress of surface layer of fine aggregate concrete, which reduces the possibility of concrete cracking.
However, it should be noted that the reduction of splitting tensile strength will decrease the ability of surface layer of fine aggregate concrete to resist cracking.
The largest relative differential of cubic and axial compressive strengths of all concrete are 9.6 % and 8.8 %, which are in the range of allowable error of statistical calculation for test data.
There is positive effect of the lower elastic modulus on the reduction of tensile thermal stress of surface layer of fine aggregate concrete, which reduces the possibility of concrete cracking.
However, it should be noted that the reduction of splitting tensile strength will decrease the ability of surface layer of fine aggregate concrete to resist cracking.
Online since: April 2015
Authors: Jiří Zach, Jitka Hroudová, Martin Sedlmajer, Ester Helanová, Martina Reif
The use of alternative binders in plaster materials, such as metakaolin, slag or fly ash represents a significant reduction in the energy demands of the production of these surface materials; with the application of natural fibres should bring a reduction in the occurrence of microcracks during contraction and increased cohesion.
Based on the obtained data it can be stated that as far as fresh plaster mortars go, values very close to the reference mixture R were reached, whether in terms of bulk density of fresh mortar, or the consistency and air content in the fresh mortar.
In terms of the obtained values of hardened mortars, it can be said that the plasters with natural fibres saw a reduction in the values of mechanical properties in comparison with the reference mixture, however, there was an increase in thermal insulation properties despite the small difference in the values of bulk density of the hardened mortars.
Based on the obtained data it can be stated that as far as fresh plaster mortars go, values very close to the reference mixture R were reached, whether in terms of bulk density of fresh mortar, or the consistency and air content in the fresh mortar.
In terms of the obtained values of hardened mortars, it can be said that the plasters with natural fibres saw a reduction in the values of mechanical properties in comparison with the reference mixture, however, there was an increase in thermal insulation properties despite the small difference in the values of bulk density of the hardened mortars.