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Online since: September 2012
Authors: Wolfgang Anwand, Gerhard Brauer, S. May Tal Beck, Andreas Wagner, O. Hen, S. Haroush, Y. Eisen, D. Moreno, A. Beck, A. Ocherashvili
The AN sample contained equi-axed grains with grain sizes of about 3-5 μm, and a few dislocations in the bulk.
In the AN sample, a microstructure of three grains is seen, with one dislocation.
The simulation of the relative number of annihilation events, using GEANT4 [39], resulted in a total of 10.3% in the Al sealed source and the Hostaphan foils.
Numbers with no errors were fixed in the fit.
This is about the maximum number of components the fitting procedure can handle.
In the AN sample, a microstructure of three grains is seen, with one dislocation.
The simulation of the relative number of annihilation events, using GEANT4 [39], resulted in a total of 10.3% in the Al sealed source and the Hostaphan foils.
Numbers with no errors were fixed in the fit.
This is about the maximum number of components the fitting procedure can handle.
Online since: March 2018
Authors: Sergey Sidelnikov, Roman Galiev, Andrey Bersenev, Denis Voroshilov
Analysis of technical and economic indicators showed that this method has a number of advantages in comparison with traditional technologies of semicontinuous extruding and continuous casting-rolling.
Developed technologies based on the method twin roll casting-extruding now are tested in a laboratory of combined treatment methods in School of Non-ferrous Metals and Material Science in Siberian federal university and industrial conditions of a number of metallurgical plants.
The schemes of combined treatment of aluminum and its alloys with the use of injection molding and metal forming operations are currently the main ones for the production of long billets with a small cross-sectional area in order to form a fine-grained structure of the casting due to high crystallization rates and subsequent metal deformation in rolls.
These schemes have undeniable technical and economic advantages as compared to traditional technologies the number of subsequent metal processing operations is reduced.
Device for continuous casting, rolling and extruding using a two-roll crystallizer: 1 – holding furnace; 2 – regulator; 3 – roll with a stream; 4 – roll with the protrusion; 5 – frame; 6 – cavity for cooling of rolls; 7 – matrix; 8 – wedge-shaped cavities; 9 – clamping mechanism; 10 – guide rollers; 11 – coiler On the basis of the above technical solutions the unit of combined casting and rolling-extruding CCRE-2,5 was designed and manufactured [16], on which a number of experimental studies on obtaining longish deformed semi-finished products from an aluminum alloy 6082 realized.
Developed technologies based on the method twin roll casting-extruding now are tested in a laboratory of combined treatment methods in School of Non-ferrous Metals and Material Science in Siberian federal university and industrial conditions of a number of metallurgical plants.
The schemes of combined treatment of aluminum and its alloys with the use of injection molding and metal forming operations are currently the main ones for the production of long billets with a small cross-sectional area in order to form a fine-grained structure of the casting due to high crystallization rates and subsequent metal deformation in rolls.
These schemes have undeniable technical and economic advantages as compared to traditional technologies the number of subsequent metal processing operations is reduced.
Device for continuous casting, rolling and extruding using a two-roll crystallizer: 1 – holding furnace; 2 – regulator; 3 – roll with a stream; 4 – roll with the protrusion; 5 – frame; 6 – cavity for cooling of rolls; 7 – matrix; 8 – wedge-shaped cavities; 9 – clamping mechanism; 10 – guide rollers; 11 – coiler On the basis of the above technical solutions the unit of combined casting and rolling-extruding CCRE-2,5 was designed and manufactured [16], on which a number of experimental studies on obtaining longish deformed semi-finished products from an aluminum alloy 6082 realized.
Online since: August 2014
Authors: Ou Chen Cai
Electrostatic and steric repulsion forces inhibit aggregation and attachment of particles to grain surfaces [35, 36].
Nelson and Ginn [60] formulated a correlation equation to predict the collector contact efficiency () for colloid filtration in Happel’s sphere-in-cell porous media model: (2) where is a factor accounting for the particle flux into the Happel sphere, is , is porosity, is a function of porosity accounting for the impact of neighboring grains on the flow field, is a dimensionless number characterizing the van der Waals force, is a dimensionless number characterizing the effect of relative particle and collector sizes, is , is a dimensionless number characterizing the effect of gravitational sedimentation, and is a dimensionless number characterizing the effect of Brownian diffusion.
Several soil properties, including grain size and pore size distribution, porosity, mineralogy, organic matter content, and hydraulic conductivity, will be measured using standard methods.
Nelson and Ginn [60] formulated a correlation equation to predict the collector contact efficiency () for colloid filtration in Happel’s sphere-in-cell porous media model: (2) where is a factor accounting for the particle flux into the Happel sphere, is , is porosity, is a function of porosity accounting for the impact of neighboring grains on the flow field, is a dimensionless number characterizing the van der Waals force, is a dimensionless number characterizing the effect of relative particle and collector sizes, is , is a dimensionless number characterizing the effect of gravitational sedimentation, and is a dimensionless number characterizing the effect of Brownian diffusion.
Several soil properties, including grain size and pore size distribution, porosity, mineralogy, organic matter content, and hydraulic conductivity, will be measured using standard methods.
Online since: July 2011
Authors: Jian Wei Zhang, Min Jie Zhu, Li Wei Zhang
According to the report, the selected pile length is 8 meter, the total number of piles is 12240 root.
FA should be fully chopped and ensure reinforcement strength and uniformity. 5.2 Quality inspection 5.2.1 Original construction record Original construction records must be exhaustive, perfect, truthfully record and timely summary analysis, if found that something do not comply with requirements and immediately correct. 5.2.3 Excavation inspection To select a certain number of pile inspection, measuring pile diameter, the pile should be continuously , close-grained, have solid feeling, don’t allow to appear powder spraying unevenness or leak phenomenon, pile location deviation within 50mm, the vertical degree deviation no greater than the 1.5% of pile length. 5.2.3 strength test Random to cut and take style 28d cube in the unconfined compressive strength test. 5.2.4 static load test 7d after making pile, the pile static load test demands to be done according to 1% of pile numbers.
Table 1: Static Load Test Results of Single Pile Project: Xinmei Plant Test Dots: J-30c Date**-06-08 Linking Piece Area 1.20m2 Replacement Rate1.000 NO bearing capacity (kPa) Lasted time (min) Settlement (mm) unit cumulation unit cumulation 0 0 0 0 0.00 0.00 1 30 61 61 1.89 1.89 2 60 61 122 0.61 2.50 3 90 61 183 0.86 3.36 4 120 61 244 0.76 4.12 5 150 61 305 0.79 4.91 6 180 61 366 0.76 5.67 7 210 61 427 0.81 6.48 8 240 61 488 0.85 7.33 9 150 30 518 -0.22 7.11 10 60 30 548 -1.32 5.79 11 0 60 608 -3.27 2.52 Maximum Settlement: 7.33mm Biggest Rebound Quantity: 4.81mm Rebound rate :65.62% 5.2.5 Dynamic load test According to the number of piles of 10% to make a pile inspection of small strain dynamic test, and to test the strength of pile body and uniformity.
FA should be fully chopped and ensure reinforcement strength and uniformity. 5.2 Quality inspection 5.2.1 Original construction record Original construction records must be exhaustive, perfect, truthfully record and timely summary analysis, if found that something do not comply with requirements and immediately correct. 5.2.3 Excavation inspection To select a certain number of pile inspection, measuring pile diameter, the pile should be continuously , close-grained, have solid feeling, don’t allow to appear powder spraying unevenness or leak phenomenon, pile location deviation within 50mm, the vertical degree deviation no greater than the 1.5% of pile length. 5.2.3 strength test Random to cut and take style 28d cube in the unconfined compressive strength test. 5.2.4 static load test 7d after making pile, the pile static load test demands to be done according to 1% of pile numbers.
Table 1: Static Load Test Results of Single Pile Project: Xinmei Plant Test Dots: J-30c Date**-06-08 Linking Piece Area 1.20m2 Replacement Rate1.000 NO bearing capacity (kPa) Lasted time (min) Settlement (mm) unit cumulation unit cumulation 0 0 0 0 0.00 0.00 1 30 61 61 1.89 1.89 2 60 61 122 0.61 2.50 3 90 61 183 0.86 3.36 4 120 61 244 0.76 4.12 5 150 61 305 0.79 4.91 6 180 61 366 0.76 5.67 7 210 61 427 0.81 6.48 8 240 61 488 0.85 7.33 9 150 30 518 -0.22 7.11 10 60 30 548 -1.32 5.79 11 0 60 608 -3.27 2.52 Maximum Settlement: 7.33mm Biggest Rebound Quantity: 4.81mm Rebound rate :65.62% 5.2.5 Dynamic load test According to the number of piles of 10% to make a pile inspection of small strain dynamic test, and to test the strength of pile body and uniformity.
Online since: May 2011
Authors: Juan Li Deng, Lai Fei Cheng, Li Ning Gao, Ke He Su
All of these analyses show that the properties (i.e. grain size, composition, texture) depend on the selection of deposition conditions (e.g., the system temperature, pressure and gas mixture composition) [20-30].
min (1) where s is the total number of the condensed-phase species, N is total number of the species in the system (consequently the number of gaseous species is N-s), p is the total pressure, ni is the moles of the ith gaseous species and nicond is the moles of the ith condensed-phase species satisfying where aij is the atomicity of element j in species i, Bj is the total atomicity of element j and M is the total number of different elements.
min (1) where s is the total number of the condensed-phase species, N is total number of the species in the system (consequently the number of gaseous species is N-s), p is the total pressure, ni is the moles of the ith gaseous species and nicond is the moles of the ith condensed-phase species satisfying where aij is the atomicity of element j in species i, Bj is the total atomicity of element j and M is the total number of different elements.
Online since: July 2011
Authors: Zheng Liu, Xiao Mei Liu
It is seen from Fig.1b that there are several of phases in the composite: the number 1, 2, 3 and 4 represent primary Mg2Si, eutectic Mg2Si, eutectic and α-Al, respectively.
Eutectic presents the big agglomerate (as shown in Fig.1b number 3).
RE2O3 can serve as nuclei of Mg2Si during the composite solidification to increase number of Mg2Si nuclei, so that the size of Mg2Si reduces.
The numbers of Mg2Si increase after modification.
Ca has obvious effect on refining grain, and can depress oxidization of melt as well as improves the creep resistance of aluminum alloy.
Eutectic presents the big agglomerate (as shown in Fig.1b number 3).
RE2O3 can serve as nuclei of Mg2Si during the composite solidification to increase number of Mg2Si nuclei, so that the size of Mg2Si reduces.
The numbers of Mg2Si increase after modification.
Ca has obvious effect on refining grain, and can depress oxidization of melt as well as improves the creep resistance of aluminum alloy.
Online since: April 2014
Authors: Yan Wei Yuan, Zheng Sun, Shu Jun Li, Xin Dong, Jun Ning Zhang, Li Ming Zhou
(1)
Where
n—number of photoelectric sensors;
n’—number of sensors conduction;
h—distance of outlet to center;
R—radius.
Tab.1 Moisture of cotton seed samples Sample number 1 2 3 4 Moisture content before drying [%] 18.42 18.25 17.57 17.97 The drying time, roller temperature, moisture and energy consumption of two different methods are shown in Table 2.
Modeling of soybean seed drying in concurrent sliding bed dryers: Effect of the number of stages on the seed quality and drying performance [J].
System characteristics analysis of the dynamic thermal signal mixed flow grain drying tower [J].
Tab.1 Moisture of cotton seed samples Sample number 1 2 3 4 Moisture content before drying [%] 18.42 18.25 17.57 17.97 The drying time, roller temperature, moisture and energy consumption of two different methods are shown in Table 2.
Modeling of soybean seed drying in concurrent sliding bed dryers: Effect of the number of stages on the seed quality and drying performance [J].
System characteristics analysis of the dynamic thermal signal mixed flow grain drying tower [J].
Online since: December 2018
Authors: Toshihiko Sasaki
Most industrial materials are polycrystalline aggregates having infinite number of fine grains.
If a D-S ring is measured with incident X-rays inclined from the normal of the sample, the independent strain εL33 (referred to as εα below) of sufficient large number for stress calculation can be obtained from a whole D-S ring.
The number of X-ray measuring points were 405 (9 points in the rail width direction multiplying by 45 points in the rail length direction).
Acknowledgement This work was partially supported by JSPS KAKENHI Grant Numbers JP16H02309, JP16H00946, JP16K14145.
If a D-S ring is measured with incident X-rays inclined from the normal of the sample, the independent strain εL33 (referred to as εα below) of sufficient large number for stress calculation can be obtained from a whole D-S ring.
The number of X-ray measuring points were 405 (9 points in the rail width direction multiplying by 45 points in the rail length direction).
Acknowledgement This work was partially supported by JSPS KAKENHI Grant Numbers JP16H02309, JP16H00946, JP16K14145.
Online since: August 2014
Authors: Li Qiong Yang, Li Na Sun
A large number of copper ions in plant will accumulate in animal and human bodies through food chain, there will be nausea, vomiting and renal failure when the copper concentration of serum reaches 3 mg/L which result in accumulative toxicity, even the damage of blood, spinal cord and liver.
Copper limited in food hygiene standards(GB15199-94)in our country stipulates that eggs≤5 mg/kg, grain, meat, vegetables and fruits≤10 mg/kg, beans≤20 mg/kg, seafood≤50 mg/kg [6].
But with the development of industry and agriculture, the number of copper entering in the environment also increased.
And large numbers of fish downstream died because of copper tailings leakage accident of a mining company in July, 2010[8].So our country has included copper and its compounds in priority control blacklist.
The research on copper mine and its surrounding water and soil shows that the average copper content in the soil reaches 186 mg/kg[9].For example, the Dexing copper mine in Jiangxi caused intersectional pollution of water, soil and air which makes the copper concentration in soil ten times more than normal value, and this accident result in the number of death toll reaching 67 in local villagers.
Copper limited in food hygiene standards(GB15199-94)in our country stipulates that eggs≤5 mg/kg, grain, meat, vegetables and fruits≤10 mg/kg, beans≤20 mg/kg, seafood≤50 mg/kg [6].
But with the development of industry and agriculture, the number of copper entering in the environment also increased.
And large numbers of fish downstream died because of copper tailings leakage accident of a mining company in July, 2010[8].So our country has included copper and its compounds in priority control blacklist.
The research on copper mine and its surrounding water and soil shows that the average copper content in the soil reaches 186 mg/kg[9].For example, the Dexing copper mine in Jiangxi caused intersectional pollution of water, soil and air which makes the copper concentration in soil ten times more than normal value, and this accident result in the number of death toll reaching 67 in local villagers.
Online since: August 2013
Authors: Shun Xi Gao, Qing Liang Zhang
Wohler’s curve, also know as S/N curve, represents the dependence of the stress amplitude σa on the number of loading cycle to complete fracture Nf.
It was found that when a constant stress applied, the fatigue crack initiation occurred on the boundary of α-Mg grain at the notched root with the increasing of cycle numbers.
In order to show the development of microcracks on the smooth surface of polycrystals under a uniform applied stress, Yue [8] compared the development of the depth of the deepest surface feature dmax and the surface roughness Ra with fatigue cyclic number.
Stress amplitude σa Number of cycles to failure Nf No subsurface fracture Subsurface fracture region ↑ Surface roughness ↓ Rough Transition stress Rough ← Smooth Surface related fracture region Fig. 1.
It was found that when a constant stress applied, the fatigue crack initiation occurred on the boundary of α-Mg grain at the notched root with the increasing of cycle numbers.
In order to show the development of microcracks on the smooth surface of polycrystals under a uniform applied stress, Yue [8] compared the development of the depth of the deepest surface feature dmax and the surface roughness Ra with fatigue cyclic number.
Stress amplitude σa Number of cycles to failure Nf No subsurface fracture Subsurface fracture region ↑ Surface roughness ↓ Rough Transition stress Rough ← Smooth Surface related fracture region Fig. 1.