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Online since: February 2017
Authors: Astrid Pundt, Vladimir Burlaka, Kai Nörthemann
This is not only attributed to the different microstructure (surface and interfaces, grain boundaries, dislocation etc.) but also to the different stress and strain condition of the film [1-3].
But, the lower pressure conventionally should result in a smaller number of nuclei and, thus, a slower transformation kinetic [21].
While a small number of large hydrides is found in the in (semi-) coherent state, a large number of small hydrides is found in the coherent state.
In contrast to this, in the 25 nm film of Fig. 2, the hydride size is just about 100 nm and hydrogen uptake mainly leads to an increasing number of hydrides.
But, the lower pressure conventionally should result in a smaller number of nuclei and, thus, a slower transformation kinetic [21].
While a small number of large hydrides is found in the in (semi-) coherent state, a large number of small hydrides is found in the coherent state.
In contrast to this, in the 25 nm film of Fig. 2, the hydride size is just about 100 nm and hydrogen uptake mainly leads to an increasing number of hydrides.
Online since: April 2014
Authors: Li Jun Yang, Xin An Dang, Ze Hui Zhang, Lin Li
Metal produce a large number of atoms in the ion rapid evaporation, but before these atoms arrive in substrate, the atoms can’t be completely ionized.
As the current increases, the number and size of particles significantly increase.
Because of the reduction of particle number and size, the raised surface film barrier greatly reduces, the friction coefficient decreases in the process of friction and wear, at the same time, spalled grains causes dramatic changes in the surface morphology of films, the particle size and number which in the film is rarely, the fluctuation of friction coefficient decreases.
As the current increases, the number and size of particles significantly increase.
Because of the reduction of particle number and size, the raised surface film barrier greatly reduces, the friction coefficient decreases in the process of friction and wear, at the same time, spalled grains causes dramatic changes in the surface morphology of films, the particle size and number which in the film is rarely, the fluctuation of friction coefficient decreases.
Online since: July 2003
Authors: P. Lin, Chun An Tang
Although the rock can be regarded as an isotropic elastic-brittle solid at macrolevel,
while the individual grains in rock are distinguished at micro-level or meso-level [12].
It can be written as following Eq.(3): c t c r c D ε ε ε ε ε ε ε ε εξ ε ≤ ≥ ≥ ≤ ⋅ = , , , 1 0 )( (3) Fig.2 Thermoelastic damage model of RVE S S σ ε0 ε St Fig.1 Density function of RVE strength h=30 h=10 h=1.1 h=6 h=3 Journal Title and Volume Number (to be inserted by the publisher) 3 where εc and εc are the strains at peak strength under compression and tension, respectively; ξ is the coefficient of residual strength under compression.
The total number of loading and unloading steps is 720.
During reloading up, the number of broken elements is not increased till the loading reaches the maximum stress level of last cycle (see Fig.4b).
The prolongations of the paths of all the cyclic loading trend to the 5th Cycle 3 rd Cycle 2nd Cycle Percentage of strength (%) Percentage of strength (%) 0 16 32 48 86 100 Fig.4 Numerical results of AE counts vs. percentage of strength 1st Cycle 6th 4th Cycle 60 0 16 32 48 86 100 60 70 50 30 10 0 60 40 20 70 50 30 10 0 60 40 20 70 50 30 10 0 60 40 20 AE counts (time) AE counts (time) AE counts (time) Fig.5 Experimental curves of AE counts under cycle loading Percentage of strength (%) Percentage of strength (%) AE counts (×1000) AE counts (×1000) AE counts (×1000) AE counts (×1000) Journal Title and Volume Number (to be inserted by the publisher) 5 original point of coordinate.
It can be written as following Eq.(3): c t c r c D ε ε ε ε ε ε ε ε εξ ε ≤ ≥ ≥ ≤ ⋅ = , , , 1 0 )( (3) Fig.2 Thermoelastic damage model of RVE S S σ ε0 ε St Fig.1 Density function of RVE strength h=30 h=10 h=1.1 h=6 h=3 Journal Title and Volume Number (to be inserted by the publisher) 3 where εc and εc are the strains at peak strength under compression and tension, respectively; ξ is the coefficient of residual strength under compression.
The total number of loading and unloading steps is 720.
During reloading up, the number of broken elements is not increased till the loading reaches the maximum stress level of last cycle (see Fig.4b).
The prolongations of the paths of all the cyclic loading trend to the 5th Cycle 3 rd Cycle 2nd Cycle Percentage of strength (%) Percentage of strength (%) 0 16 32 48 86 100 Fig.4 Numerical results of AE counts vs. percentage of strength 1st Cycle 6th 4th Cycle 60 0 16 32 48 86 100 60 70 50 30 10 0 60 40 20 70 50 30 10 0 60 40 20 70 50 30 10 0 60 40 20 AE counts (time) AE counts (time) AE counts (time) Fig.5 Experimental curves of AE counts under cycle loading Percentage of strength (%) Percentage of strength (%) AE counts (×1000) AE counts (×1000) AE counts (×1000) AE counts (×1000) Journal Title and Volume Number (to be inserted by the publisher) 5 original point of coordinate.
Online since: April 2011
Authors: Carlos José de Araújo, Antonio Almeida Silva, Bruno Allison Araújo, Gabriel Dias Travassos, Eudésio Oliveira Vilar, Jorge Palma Carrasco
It is known that alloys designed to resist to hydrogen embrittlement must have a large number of harmless trapping and that these should preferably be irreversible and well distributed through the microstructure [8].
Additions of elements that are carbides formers, which are used for grain refinement, precipitation hardening and improves the toughness, also provide irreversible trapping for hydrogen.
The main features are the largest number of dimples in API 5L X60 steel and the presence of cracks on the fracture surfaces of API 5L X80 steel.
It can be noted that the effect of hydrogen was to increase the number of dimples in the hydrogenated samples, and this effect was more pronounced in the API 5L X60 steel.
Hydrogen accumulates in particle-matrix interfaces, which in turn contributes to the reduction of interfacial resistance of the particles, causing a larger number of dimples.
Additions of elements that are carbides formers, which are used for grain refinement, precipitation hardening and improves the toughness, also provide irreversible trapping for hydrogen.
The main features are the largest number of dimples in API 5L X60 steel and the presence of cracks on the fracture surfaces of API 5L X80 steel.
It can be noted that the effect of hydrogen was to increase the number of dimples in the hydrogenated samples, and this effect was more pronounced in the API 5L X60 steel.
Hydrogen accumulates in particle-matrix interfaces, which in turn contributes to the reduction of interfacial resistance of the particles, causing a larger number of dimples.
Online since: August 2022
Authors: Rostislav Drochytka, Vit Černý, Pavel Dohnálek, Petr Figala
Introduction
Degradation and the associated rehabilitation of building structures of sewerage systems is a current problem, which is addressed by a large number of studies and manufacturers of building materials.
Fine-grained additives (microsilica, micronized limestone, stone fillers) are usually used as additives to improve the adhesion properties and increase the density of the cement composite.
These are a number of biological, physical, or chemical processes with microscopic and macroscopic manifestations.
This was due to the application in pilot plant conditions, and a more significant number of factors probably had an effect on the degree of inhomogeneity.
Before starting the chemical loading itself, measuring pegs were mounted on the required number of test specimens (10x40x160mm) (Fig. 3).
Fine-grained additives (microsilica, micronized limestone, stone fillers) are usually used as additives to improve the adhesion properties and increase the density of the cement composite.
These are a number of biological, physical, or chemical processes with microscopic and macroscopic manifestations.
This was due to the application in pilot plant conditions, and a more significant number of factors probably had an effect on the degree of inhomogeneity.
Before starting the chemical loading itself, measuring pegs were mounted on the required number of test specimens (10x40x160mm) (Fig. 3).
Online since: November 2015
Authors: George Constantin, Eugen Madalin Galitu
Introduction
This paper proposes methods to reduce the number of main defects found in the casting of the type of gearbox housing part.
For having o good productivity a MMF below 17.6% commitment and 14.1% monthly target respectively, represented in Fig. 7, where 349-405 represent the batch number of the worked day.
It is found that shell temperature should be in the range 180°-260°C in order to decrease the number of scraps with 10%.
To significantly reduce the number of rejected the required casting speed should be respected: the optimal casting speed in Phase I of 0.22 m/s gear, optimal casting speed in Phase II of 3.35 m/s, and multiplication pressure of 912 bar.
[8] High Pressure Die Casting of Aluminium and Magnesium Alloys-Grain Structure and Segregation Characteristics, Hans Ivar Laukli, Trondheim, April, 2004.
For having o good productivity a MMF below 17.6% commitment and 14.1% monthly target respectively, represented in Fig. 7, where 349-405 represent the batch number of the worked day.
It is found that shell temperature should be in the range 180°-260°C in order to decrease the number of scraps with 10%.
To significantly reduce the number of rejected the required casting speed should be respected: the optimal casting speed in Phase I of 0.22 m/s gear, optimal casting speed in Phase II of 3.35 m/s, and multiplication pressure of 912 bar.
[8] High Pressure Die Casting of Aluminium and Magnesium Alloys-Grain Structure and Segregation Characteristics, Hans Ivar Laukli, Trondheim, April, 2004.
Online since: August 2019
Authors: Muralimohan Cheepu, D. Venkateswarlu, Narayanan Srinivasan, S. Senthil Kumaran, P. Nageswara Rao
Using design of experiments, number of runs are decided and the regression models are identified to predict the optimal microstructural zones and its widths along the fusion zone.
The range of welding conditions were decided based on the large number of experimental trails.
Design of experiments (DOE) was used which is a selected as a right approach to decide the number of tests and helps to determine the effect of each parameter and develops the relationships between input and output conditions.
Response surface methodology (RSM) is one of the easiest method among the DOE techniques, with this the minimum number of experimental trails can be decided with the approximate values of the known input process parameters.
The size of the grain increasing from fusion zone to towards the base metal.
The range of welding conditions were decided based on the large number of experimental trails.
Design of experiments (DOE) was used which is a selected as a right approach to decide the number of tests and helps to determine the effect of each parameter and develops the relationships between input and output conditions.
Response surface methodology (RSM) is one of the easiest method among the DOE techniques, with this the minimum number of experimental trails can be decided with the approximate values of the known input process parameters.
The size of the grain increasing from fusion zone to towards the base metal.
Online since: December 2011
Authors: Fang Ying Ji, Jun Ren Zhu, Zhen Zhen Jiang, Ming Zhuo Tan, Yong Jun Sun, Shu Xiang Miao, Xiao Kai Zheng, Huai Li Zheng
A large number of tailings have been produced from concentrator, without proper dealing with them that should inevitably lead to serious environmental pollution, ecological damage and safety issues[1].
But this production method needs a large number of organic solvent, higher production cost, and more complex technology.
And a number of organic or inorganic dispersion stabilizers are used, which affected the purity of CPAM.
However, fine grains linked into the tighter floc in tailings because of excessive use of polyacrylamide, which had a negative impact on the stability of tailings dams.
Our research group carried out a number of preparation and application research of CPAM[24-25], included that the synthesis of cationic polyacrylamide by dispersion polymerization.
But this production method needs a large number of organic solvent, higher production cost, and more complex technology.
And a number of organic or inorganic dispersion stabilizers are used, which affected the purity of CPAM.
However, fine grains linked into the tighter floc in tailings because of excessive use of polyacrylamide, which had a negative impact on the stability of tailings dams.
Our research group carried out a number of preparation and application research of CPAM[24-25], included that the synthesis of cationic polyacrylamide by dispersion polymerization.
Online since: December 2013
Authors: Qing Qiu Kong, Guo Jun Ke, Dan Wang
When pressure was up to 2.94 ~ 9.8MPa or more, the stable glass can be damaged violently in short term, and a large number of SiO2 was released into the solution at the same time.
The density was 2.49 g/cm3, specific surface area 4215 cm2/g, grain diameter less than 100μm and the medium particle size 12.1μm.
Table2 Mix proportion Code number Cement (g) Standard sand (g) Activated glass powder (g) Unactivated glass powder (g) Water (g) C 450 1350 0 0 225 NHGP1 450 1350 0 45 225 NHGP2 360 1350 0 90 225 HGPD(108℃,0.15MPa) 360 1350 90 0 225 HGPE(116℃,0.18MPa) 360 1350 90 0 225 HGPF(121℃,0.20MPa) 360 1350 90 0 225 N-non; H-hydrothermal activated; G-glass; P-powder; D, E, F- Code number In this paper, the cementitious material was produced by waste glass powder in equivalent replacement of cement, such as untreated glass powder 0% (Code No.
Results and discussion Table.3 List of relationship between mortar specimen compressive strength and age Code number Compressive Strength(MPa) Age(d) 3 7 14 28 90 C 22.0 23.9 32.1 39.3 42.8 NHGP1 14.4 20.3 27.7 33.5 42.6 NHGP2 13.2 17.8 25.3 27.9 36.1 HGPD 13.9 18.2 25.7 29.8 39.6 HGPE 14.3 18.4 26.1 30.1 40.9 HGPF 15.0 19.0 26.4 30.6 42.5 Effect of undisturbed glass powder on mortar specimen compressive strength.
The density was 2.49 g/cm3, specific surface area 4215 cm2/g, grain diameter less than 100μm and the medium particle size 12.1μm.
Table2 Mix proportion Code number Cement (g) Standard sand (g) Activated glass powder (g) Unactivated glass powder (g) Water (g) C 450 1350 0 0 225 NHGP1 450 1350 0 45 225 NHGP2 360 1350 0 90 225 HGPD(108℃,0.15MPa) 360 1350 90 0 225 HGPE(116℃,0.18MPa) 360 1350 90 0 225 HGPF(121℃,0.20MPa) 360 1350 90 0 225 N-non; H-hydrothermal activated; G-glass; P-powder; D, E, F- Code number In this paper, the cementitious material was produced by waste glass powder in equivalent replacement of cement, such as untreated glass powder 0% (Code No.
Results and discussion Table.3 List of relationship between mortar specimen compressive strength and age Code number Compressive Strength(MPa) Age(d) 3 7 14 28 90 C 22.0 23.9 32.1 39.3 42.8 NHGP1 14.4 20.3 27.7 33.5 42.6 NHGP2 13.2 17.8 25.3 27.9 36.1 HGPD 13.9 18.2 25.7 29.8 39.6 HGPE 14.3 18.4 26.1 30.1 40.9 HGPF 15.0 19.0 26.4 30.6 42.5 Effect of undisturbed glass powder on mortar specimen compressive strength.
Online since: February 2026
Authors: Ammar Bensakhria, Ansoumane Diedhiou, Jeanne Marie Annick Troh
Evolution curve of the Conductivity (μS/cm) of the substrates as a function of the number of day.
Salinity evolution curve of substrates as a function of the number of day.
TDS (mg/L) evolution curve of substrates as a function of the number of day.
Curve of evolution of the pH of the substrates as a function of the number of day.
Khan et al., « Associative effects of lignin-derived biochar and arbuscular mycorrhizal fungi applied to soil polluted from Pb-acid batteries effluents on barley grain safety », Sci.
Salinity evolution curve of substrates as a function of the number of day.
TDS (mg/L) evolution curve of substrates as a function of the number of day.
Curve of evolution of the pH of the substrates as a function of the number of day.
Khan et al., « Associative effects of lignin-derived biochar and arbuscular mycorrhizal fungi applied to soil polluted from Pb-acid batteries effluents on barley grain safety », Sci.