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Online since: September 2013
Authors: Chang Ying Shi, Li Juan Wang
Table 1 Reborn coarse aggregate gradation of grain
Aperture Size, mm
16
10
5
2.5
Lower Limit in the Standard,%
0
0
80
95
Up Limit in the Standard,%
0
15
100
100
CumulativeSieveResidue of Sample 1,%
0
4
92
100
CumulativeSieveResidue of Sample 2,%
0
3
90
100
CumulativeSieveResidue of Sample 3,%
0
7
96
100
Table 2 Reborn coarse aggregate technical criteria
Sample Number
Bulk Density, kg/m3
Crushing Index,%
Needle and Plate Particle content,%
Powder Content,%
Macadam
1490
10.5
6.7
0.3
No.1
1360
13.6
5.4
0.28
No.2
1274
22.7
2.9
0.43
No.3
1170
31.2
3.8
0.73
Table 3 Reborn fine aggregate gradation of grain
Aperture Size, mm
10
5
2.5
1.25
0.63
0.315
0.16
Fineness Modulus
Lower Limit in the Standard,%
0
0
0
10
41
70
90
Up Limit in the Standard,%
0
10
25
50
70
92
100
Cumulative Sieve Residue of Sample 1,%
0
7
15
23
48
75
94
2.4
Cumulative Sieve Residue of Sample 2,%
0
6
13
21
45
73
95
2.3
Cumulative Sieve Residue of Sample 3,%
0
3
10
16
46
72
93
2.3
Table 4 Reborn fine aggregate technical
criteria Sample Number Bulk Density, kg/m3 Crushing Index,% Powder Content,% Medium Sand 1430 - 6.7 No.1 1325 12.4 2.2 No.2 1285 21.4 4.3 No.3 1205 27.6 6.1 Table 5 Reborn coarse aggregate class Item Class Bulk Density, kg/m3 Crushing Index,% Needle and Plate Particle content,% Powder Content,% I ≥1350 ≤15 ≤5 ≤0.5 II ≥1250 ≤25 ≤10 ≤1.0 III ≥1150 ≤35 ≤20 ≤1.5 Table 6 Reborn fine aggregate class Item Class Bulk Density, kg/m3 Crushing Index,% Powder Content,% I ≥1350 ≤20 ≤3.0 II ≥1250 ≤28 ≤5.0 III ≥1150 ≤35 ≤7.0 Research on the Production and Performance Testing of Concrete Block.
MU3.5 01 3.10W/m2·K MU3.5 02 2.80W/m2·K Table 8 Reborn building block physical property of mu10 Experiment Note Measured Value 1 Measured Value 2 Measured Value 3 Measured Value 4 Measured Value 5 Mean Value Compressive Strength, MPa MU10 03 12.6 13.0 13.3 11.7 13.8 12.9 MU10 04 11.6 13.2 11.8 11.0 10.6 11.6 Density, kg/m3 MU10 03 1186 1129 1243 1193 1165 1183 MU10 04 1112 1087 1129 1225 1164 1144 Percent Sorption % MU10 03 9.8 11.4 10.0 10.4 MU10 04 11.5 12.3 12.8 12.2 Relative Water Content,% MU10 03 31 29 29 30 MU10 04 32 33 32 32 Coefficient of Softening MU10 03 0.97 0.96 0.93 0.94 0.95 0.95 MU10 04 0.90 0.93 0.92 0.91 0.93 0.92 Compressive Strength Loss Percentage of F15,% MU10 03 loss free in compressive strength MU10 04 loss free in compressive strength Quality Loss Percentage of F15,% MU10 03 loss free in quality MU10 04 loss free in quality Thermal Conductivity of 190mm Thick MU10 03 4.12W/m2·K MU10 04 3.85W/m2·K Table 9 Reborn building block mixing proportion of mu3.5 Mix Number
Slag Cement 32.5 Reborn Coarse Aggregate Reborn Fine Aggregate Fly Ash Water MU3.5 01 220 No.3 460 No.3 376 88 300 MU3.5 02 200 No.3 475 No.3 389 80 300 Table 10 Reborn building block mixing proportion of mu10 Mix Number Slag Cement 32.5 Reborn Coarse Aggregate Reborn Fine Aggregate Fly Ash Water MU10 03 370 No.1 828 No.1 678 74 150 MU10 04 350 No.1 842 No.1 688 70 150 Conclusions This project divided recycled aggregate prepared from construction waste into recycled coarse aggregate and recycled fine aggregate, and then three categories were identified, according to the difference on the technical specifications of the bulk density, crushing index, flakiness particle content.
criteria Sample Number Bulk Density, kg/m3 Crushing Index,% Powder Content,% Medium Sand 1430 - 6.7 No.1 1325 12.4 2.2 No.2 1285 21.4 4.3 No.3 1205 27.6 6.1 Table 5 Reborn coarse aggregate class Item Class Bulk Density, kg/m3 Crushing Index,% Needle and Plate Particle content,% Powder Content,% I ≥1350 ≤15 ≤5 ≤0.5 II ≥1250 ≤25 ≤10 ≤1.0 III ≥1150 ≤35 ≤20 ≤1.5 Table 6 Reborn fine aggregate class Item Class Bulk Density, kg/m3 Crushing Index,% Powder Content,% I ≥1350 ≤20 ≤3.0 II ≥1250 ≤28 ≤5.0 III ≥1150 ≤35 ≤7.0 Research on the Production and Performance Testing of Concrete Block.
MU3.5 01 3.10W/m2·K MU3.5 02 2.80W/m2·K Table 8 Reborn building block physical property of mu10 Experiment Note Measured Value 1 Measured Value 2 Measured Value 3 Measured Value 4 Measured Value 5 Mean Value Compressive Strength, MPa MU10 03 12.6 13.0 13.3 11.7 13.8 12.9 MU10 04 11.6 13.2 11.8 11.0 10.6 11.6 Density, kg/m3 MU10 03 1186 1129 1243 1193 1165 1183 MU10 04 1112 1087 1129 1225 1164 1144 Percent Sorption % MU10 03 9.8 11.4 10.0 10.4 MU10 04 11.5 12.3 12.8 12.2 Relative Water Content,% MU10 03 31 29 29 30 MU10 04 32 33 32 32 Coefficient of Softening MU10 03 0.97 0.96 0.93 0.94 0.95 0.95 MU10 04 0.90 0.93 0.92 0.91 0.93 0.92 Compressive Strength Loss Percentage of F15,% MU10 03 loss free in compressive strength MU10 04 loss free in compressive strength Quality Loss Percentage of F15,% MU10 03 loss free in quality MU10 04 loss free in quality Thermal Conductivity of 190mm Thick MU10 03 4.12W/m2·K MU10 04 3.85W/m2·K Table 9 Reborn building block mixing proportion of mu3.5 Mix Number
Slag Cement 32.5 Reborn Coarse Aggregate Reborn Fine Aggregate Fly Ash Water MU3.5 01 220 No.3 460 No.3 376 88 300 MU3.5 02 200 No.3 475 No.3 389 80 300 Table 10 Reborn building block mixing proportion of mu10 Mix Number Slag Cement 32.5 Reborn Coarse Aggregate Reborn Fine Aggregate Fly Ash Water MU10 03 370 No.1 828 No.1 678 74 150 MU10 04 350 No.1 842 No.1 688 70 150 Conclusions This project divided recycled aggregate prepared from construction waste into recycled coarse aggregate and recycled fine aggregate, and then three categories were identified, according to the difference on the technical specifications of the bulk density, crushing index, flakiness particle content.
Online since: May 2006
Authors: Elena Dimitriu, Alin Iuga
If the number of oxygen vacancies is great, new phases might appear.
It seems that, in the MPT01 material, the number of these oxygen vacancies is small, because a single perovskite phase is present.
Fig. 3 shows a typical compact PZT texture, with well-delimited grains of about 2.5-5µm.
Some pores are visible along the grain boundaries.
The spectrum of the transducer is 2.6 kHz wide with a relative bandwidth of 6 %, i.e. an acoustical Q number of 15.
It seems that, in the MPT01 material, the number of these oxygen vacancies is small, because a single perovskite phase is present.
Fig. 3 shows a typical compact PZT texture, with well-delimited grains of about 2.5-5µm.
Some pores are visible along the grain boundaries.
The spectrum of the transducer is 2.6 kHz wide with a relative bandwidth of 6 %, i.e. an acoustical Q number of 15.
Online since: February 2006
Authors: Ying Qin, Jian Feng Chen, Peng Yuan Zhang
Introduction
Materials with a grain size in the nanometer range, popularly known as nanostructured materials,
are being intensively researched in recent years.
The average grain diameter of the products obtained by different molar ratio of PVP monomer units to CuSO4 was as follows: 314.6nm, 58.4nm, 28.6nm and 28.4nm, and particle size distribution was shown in Fig. 5.
This can be explained as follows: when the ratio was 8:1 or 16:1, the entire surface of the particles was coated by PVP, the steric effect of PVP against the agglomeration and growth was fulfilled and the copper particles were smaller and separated from each other by PVP [7]. 80 160 240320400 0 5 10 15 20 25 30 35 40 diameter (nm) number of particles (a) 10 100 0 5 10 15 20 25 30 number of particles diameter (nm)(b) 10 20 30 40 50 60 0 10 20 30 40 50 60 70 80 diameter (nm) number of particles (c) 10 20 30 40 50 60 0 10 20 30 40 50 60 70 80 diameter (nm) number of particles (d) Conclusion In conclusion, a rapid method to synthesize nanocrystalline copper powders by reducing CuSO4 with KBH4 was developed.
The average grain diameter of the products obtained by different molar ratio of PVP monomer units to CuSO4 was as follows: 314.6nm, 58.4nm, 28.6nm and 28.4nm, and particle size distribution was shown in Fig. 5.
This can be explained as follows: when the ratio was 8:1 or 16:1, the entire surface of the particles was coated by PVP, the steric effect of PVP against the agglomeration and growth was fulfilled and the copper particles were smaller and separated from each other by PVP [7]. 80 160 240320400 0 5 10 15 20 25 30 35 40 diameter (nm) number of particles (a) 10 100 0 5 10 15 20 25 30 number of particles diameter (nm)(b) 10 20 30 40 50 60 0 10 20 30 40 50 60 70 80 diameter (nm) number of particles (c) 10 20 30 40 50 60 0 10 20 30 40 50 60 70 80 diameter (nm) number of particles (d) Conclusion In conclusion, a rapid method to synthesize nanocrystalline copper powders by reducing CuSO4 with KBH4 was developed.
Online since: July 2018
Authors: V.K. Afanasyev, O.V. Sankina
As materials for wear-resistant coatings it usually uses such expensive alloys as sormite, high-alloyed cast iron and other materials containing in their composition a large number of deficient alloying elements - chromium, nickel, tungsten, molybdenum, cobalt and others, that sharply increasing the cost of manufacturing products.
However, this type of treatment leads to high heating-up temperatures of the base metal in the adjacent part and, as a consequence, to the formation of a coarse-grained structure of the part under the thermal influence (Fig. 3).
G.; Paiva, Olga C.; and other, Study of the Heat-Treatments Effect on High Strength Ductile Cast Iron Welded Joints, Metals, Tome: 7 (9) Number of article: 382
[5] Zuk, M.; Gorka, J.; Dojka, R.; and other, Repair welding of cast iron coated electrodes, Modtech international conference – modern technologies in industrial engineering V Book series: IOP Conference Series-Materials Science and Engineering, Tome: 227 Number of article: UNSP 012139
A., Displaying structural property and inheritance of cast iron surfacing on steel base, International scientific – technical conference on innovative engineering technologies, equipment and materials 2015 (ISTC-IETEM-2015), Book series: IOP Conference Series-Materials Science and Engineering, Tome: 13, Number of article: UNSP 012037 [9] Correa, E.
However, this type of treatment leads to high heating-up temperatures of the base metal in the adjacent part and, as a consequence, to the formation of a coarse-grained structure of the part under the thermal influence (Fig. 3).
G.; Paiva, Olga C.; and other, Study of the Heat-Treatments Effect on High Strength Ductile Cast Iron Welded Joints, Metals, Tome: 7 (9) Number of article: 382
[5] Zuk, M.; Gorka, J.; Dojka, R.; and other, Repair welding of cast iron coated electrodes, Modtech international conference – modern technologies in industrial engineering V Book series: IOP Conference Series-Materials Science and Engineering, Tome: 227 Number of article: UNSP 012139
A., Displaying structural property and inheritance of cast iron surfacing on steel base, International scientific – technical conference on innovative engineering technologies, equipment and materials 2015 (ISTC-IETEM-2015), Book series: IOP Conference Series-Materials Science and Engineering, Tome: 13, Number of article: UNSP 012037 [9] Correa, E.
Online since: October 2006
Authors: Hernan A. González-Rojas, Milton Coba Salcedo, Joan Vivancos Calvet
The first stage in this research involves determining and measuring the relation between the
internal temperature of the cylinder wall and the technological variables of the process, namely
coolant temperature, ambient temperature, forced and natural convection coefficients and the
intensity and number of heat pulses.
Problem Definition We modelled a process of chip removal in which the abrasive grains of the cutting tool remove micro-chips as the tool moves over the inner surface of the cylinder being machined.
This mechanical process of removal of micro-chips involving plastic deformation and friction between the abrasive grains and the part being machined generates a great deal of heat.
The number of pulses depends on the number of abrasive stones, their rotation velocity and the frequency of their axial movement [6,7].
This is where the conditions that govern the thermal problem are defined: the internal and external radius of the cylinder, the number of nodes used in the discretisation of the domain, the integration time, the characteristics of the heat pulse function, the amplitude of the heat pulse, the inner and outer heat convection coefficients, the initial temperature of the process and the density of the material.
Problem Definition We modelled a process of chip removal in which the abrasive grains of the cutting tool remove micro-chips as the tool moves over the inner surface of the cylinder being machined.
This mechanical process of removal of micro-chips involving plastic deformation and friction between the abrasive grains and the part being machined generates a great deal of heat.
The number of pulses depends on the number of abrasive stones, their rotation velocity and the frequency of their axial movement [6,7].
This is where the conditions that govern the thermal problem are defined: the internal and external radius of the cylinder, the number of nodes used in the discretisation of the domain, the integration time, the characteristics of the heat pulse function, the amplitude of the heat pulse, the inner and outer heat convection coefficients, the initial temperature of the process and the density of the material.
Online since: April 2010
Authors: Gabriel Ferro, Patrick Fiorenza, Fabrizio Roccaforte, Filippo Giannazzo, Vito Raineri, Jens Eriksson, Jean Lorenzzi, Ming Hung Weng
Grains are visible
in the layer and the root mean square (RMS)
roughness value of the area is determined to be
0.23 nm.
Indeed, it resembles the morphology, thus indicating (provided the oxide charges are uniformly distributed in the layer) that the observed grains correspond to variations in the oxide thickness.
The density of BD spots increases upon increasing the stress time per pixel and the total area of the BD spots is proportional to the number of broken nano-MOS devices.
The number of breakdowns related to stress time has been determined in different phases of electrical stress.
The ratio between the number of failed devices, f, and the total number of stressed devices, i, was determined from the TUNA micrographs.
Indeed, it resembles the morphology, thus indicating (provided the oxide charges are uniformly distributed in the layer) that the observed grains correspond to variations in the oxide thickness.
The density of BD spots increases upon increasing the stress time per pixel and the total area of the BD spots is proportional to the number of broken nano-MOS devices.
The number of breakdowns related to stress time has been determined in different phases of electrical stress.
The ratio between the number of failed devices, f, and the total number of stressed devices, i, was determined from the TUNA micrographs.
Online since: July 2011
Authors: Yong Chen, Hong Pan, Guo Rong Wu, Zhi Qiang Li, Jian Hua Zeng
Introduction
In order to heighten the strength of low alloy steel such as automobile frame steel plate, micro alloying elements such as V, Nb and Ti are usually added into molten steel in steelmaking process, which can change the recrystalization of austenite and inhibit the growth of austenitic grain bringing grain refinement.
The variation of RHFD is shown in Fig.1, and on this condition, the defects of transverse corner cracks on casting slab (left-side and right-side) are shown in Table 2 (a) (b) Fig. 1 Variation of RHFD Table 2 statistics of transverse corner cracks on casting slab (left-side and right-side) Heat flux density in left-side/ heat flux density in broad-side Numbers of transverse corner cracks Heat flux density in right-side/ heat flux density in broad-side Numbers of transverse corner cracks (a) 0.90~1.10 35 0.75~0.85 9 (b) 0.75~0.83 10 0.85~1.00 29 It is indicated from Fig.1 and Table 2 that there is close relationship between RHFD and transverse corner cracks on casting slab for automobile frame steel plate.
Table 3 Physical properties of mold powder Basicity Melting temperature/℃ Viscosity/ Pa•s Li2O/% Before optimization 1.02 1056 0.20 1.0 After optimization 1.04 1057 0.16 1.0 Table 4 Effect of mold powder on transverse corner cracks Size of cracks/mm Number of cracks Lift-side of slab Right-side of slab Before optimization 8~40 9~51 9~45 After optimization 2~10 3~18 2~16 (a) Before he optimization (b) After the optimization Fig.3 Transverse corner cracks on slab before and after the optimization Casting speed.
Table 5 Effect of casting speed on transverse corner cracks Casting speed Size of cracks/mm Numbers of cracks Lift-side of slab Right-side of slab Big fluctuation 4~16 3~11 3~9 Stable 1~3 0~5 0~6 Stabilization of caster.
The variation of RHFD is shown in Fig.1, and on this condition, the defects of transverse corner cracks on casting slab (left-side and right-side) are shown in Table 2 (a) (b) Fig. 1 Variation of RHFD Table 2 statistics of transverse corner cracks on casting slab (left-side and right-side) Heat flux density in left-side/ heat flux density in broad-side Numbers of transverse corner cracks Heat flux density in right-side/ heat flux density in broad-side Numbers of transverse corner cracks (a) 0.90~1.10 35 0.75~0.85 9 (b) 0.75~0.83 10 0.85~1.00 29 It is indicated from Fig.1 and Table 2 that there is close relationship between RHFD and transverse corner cracks on casting slab for automobile frame steel plate.
Table 3 Physical properties of mold powder Basicity Melting temperature/℃ Viscosity/ Pa•s Li2O/% Before optimization 1.02 1056 0.20 1.0 After optimization 1.04 1057 0.16 1.0 Table 4 Effect of mold powder on transverse corner cracks Size of cracks/mm Number of cracks Lift-side of slab Right-side of slab Before optimization 8~40 9~51 9~45 After optimization 2~10 3~18 2~16 (a) Before he optimization (b) After the optimization Fig.3 Transverse corner cracks on slab before and after the optimization Casting speed.
Table 5 Effect of casting speed on transverse corner cracks Casting speed Size of cracks/mm Numbers of cracks Lift-side of slab Right-side of slab Big fluctuation 4~16 3~11 3~9 Stable 1~3 0~5 0~6 Stabilization of caster.
Online since: September 2012
Authors: Emad A. Badawi, E.M. Hassan, M.A. Abdel-Rahman, Alaa M. Ibrahim
This idea has been successfully developed in a number of positron-based techniques of physical analysis, with resolution in energy, momentum, or position [1].
Plastic deformation involves the breaking of a limited number of atomic bonds by the movement of dislocations.
Since the energy required for movement is lowest on the densest atomic planes, dislocations have a preferred direction of travel within the grains of a material.
This results in slip that occurs along parallel planes within the grain.
The reason is that resistivity increases with increasing number of imperfections in the atomic lattice structure and with temperature and this hampers electron movement.
Plastic deformation involves the breaking of a limited number of atomic bonds by the movement of dislocations.
Since the energy required for movement is lowest on the densest atomic planes, dislocations have a preferred direction of travel within the grains of a material.
This results in slip that occurs along parallel planes within the grain.
The reason is that resistivity increases with increasing number of imperfections in the atomic lattice structure and with temperature and this hampers electron movement.
Online since: January 2015
Authors: Jun Qiang Liu, Hua Zhong Li, Tao He, De Fen Zhang, Yong Wei, Li Na Fang, Shou Xiang Xu
A fine-grained analysis makes the dynamic trust model can accurately reflect the dynamic trust relationship between nodes.
Within the time frame t, the indirect trust number between entity a and entity b, can be valued by the software entities which had interactive experience on entity b within time frame t.
After a certain number of node interaction, then sample the trust data information, and input the data into Matlab, to analysis the results, until reach the recommended interaction times.
The node sets in the whole system can be shown as Nodec Nodec = {e i|1≤ i ≤ N}, then the average trust value of such nodes within time frame t is as follows: (9) Within the time frame t, the total interaction times of all the nodes in the system is M, the total number of successful interaction is S, so the successful collaboration rate is: w=s/M.
Firstly, have an overall introduction and summery on rusted and relevant knowledge, then gives the trust management framework for software entities, with this basis, think of that different services have different weights, different software entities have different roles, make a fine-grained analysis on trust metric measurement data based on time frame, and gives the recommendation credibility updating calculation based on experience factor and calculator for time frame weight based on induced ordered weighted operator.
Within the time frame t, the indirect trust number between entity a and entity b, can be valued by the software entities which had interactive experience on entity b within time frame t.
After a certain number of node interaction, then sample the trust data information, and input the data into Matlab, to analysis the results, until reach the recommended interaction times.
The node sets in the whole system can be shown as Nodec Nodec = {e i|1≤ i ≤ N}, then the average trust value of such nodes within time frame t is as follows: (9) Within the time frame t, the total interaction times of all the nodes in the system is M, the total number of successful interaction is S, so the successful collaboration rate is: w=s/M.
Firstly, have an overall introduction and summery on rusted and relevant knowledge, then gives the trust management framework for software entities, with this basis, think of that different services have different weights, different software entities have different roles, make a fine-grained analysis on trust metric measurement data based on time frame, and gives the recommendation credibility updating calculation based on experience factor and calculator for time frame weight based on induced ordered weighted operator.
Online since: March 2007
Authors: Liang Meng, J.B. Liu
Large number of the filamentary interfaces offers effective resistance to the
plastic flow in the phases [11, 14].
The eutectic colonies between the dendritic arms of primary Cu grains increased with increasing Ag concentration in the alloys.
The filaments broke locally up due to strong recrystallization at 400 ºC and changed into discontinuous clusters along wire axis due to severe propagation of recrystallized grains at 500 ºC.
Arrays of dislocations in the matrix and near interfaces were observed in the grains after superplastic deformation. 3.
At temperatures higher than 300° C, the strength decreased dramatically because recrystallizing and grain propagation removed the benefit from work hardening to result in obvious softening [33, 34, 44, 45]. 4.
The eutectic colonies between the dendritic arms of primary Cu grains increased with increasing Ag concentration in the alloys.
The filaments broke locally up due to strong recrystallization at 400 ºC and changed into discontinuous clusters along wire axis due to severe propagation of recrystallized grains at 500 ºC.
Arrays of dislocations in the matrix and near interfaces were observed in the grains after superplastic deformation. 3.
At temperatures higher than 300° C, the strength decreased dramatically because recrystallizing and grain propagation removed the benefit from work hardening to result in obvious softening [33, 34, 44, 45]. 4.