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Online since: December 2012
Authors: Svein Erik Sveen, Bjørn R Sørensen
• Cold-water thawing: the most economic deep thawing technique, but should be confined to coarse-grained soils.
Electrical thawing is most suited to fine-grained soils
Each frame has the same number and type of sensors, all of which are internally aligned to each other (sensor-to-sensor).
The numbering corresponds to Table 1 and Fig. 5.
The numbers of the sensors, their small vertical spacing and high sensitivity, allows for detection of minute changes in soil temperature and moisture levels.
Electrical thawing is most suited to fine-grained soils
Each frame has the same number and type of sensors, all of which are internally aligned to each other (sensor-to-sensor).
The numbering corresponds to Table 1 and Fig. 5.
The numbers of the sensors, their small vertical spacing and high sensitivity, allows for detection of minute changes in soil temperature and moisture levels.
Online since: April 2016
Authors: Y. Şahin, Senai Yalcinkaya
The effects of the speed, feed rate, depth of cut, grain size, number of passes and oil effect on the grinding of mostly mild steels and alloyed steels are studied [7-13].
There are numbers of studies on the grinding results of various materials mostly including carbon steels and alloyed steels, but a very limited work is carried out on plastic moulding steels by Taguchi method [5, 7, and 12].
Depth of cut was found more important, whereas the grinding speed, grain size, cutting fluid concentration and number of passes are insignificants when grinding heat treated AISI 4140 steel [7].
There are numbers of studies on the grinding results of various materials mostly including carbon steels and alloyed steels, but a very limited work is carried out on plastic moulding steels by Taguchi method [5, 7, and 12].
Depth of cut was found more important, whereas the grinding speed, grain size, cutting fluid concentration and number of passes are insignificants when grinding heat treated AISI 4140 steel [7].
Online since: December 2016
Authors: Zhesfina Blednova, Peter Olegovich Rusinov
The capabilities of these materials are related to the manifestation of shape memory effect, which has already been successfully used to create a number of next-generation devices and equipment in aerospace products, instrumentation, electronics, medicine and biotechnology, [3].
Equipment for Technology One of the effective ways to form layered nanostructure composition using shape memory materials on the engineering products is a high-velocity oxygen-fuel spraying (HVOF), which has a number of advantages: a high deposition rate, coating of large items, increased adhesion properties.
The proposed technical solutions are protected by patents of the Russian Federation (patent number № 2475567, № 2502829, № 2402628) and awarded with the Gold Medal of the International Salon of Inventions and Innovation Technologies "Archimedes-2014", with the Bronze Medal of the International Exhibition of Inventions "Concours Lepine - 2014", Paris, France.
Fig. 3 shows the effect of HVOF parameters on the adhesion strength with the substrate of the formed TiNiCu surface layers (Fig. 3a, b.) and on the characteristics of the surface layer quality: the grain size and porosity (Fig. 3, c, d).
a) b) c) d) e) f) Fig. 3 Effect of high-velocity oxygen-fuel spraying parameters on the properties of the surface layers made of shape memory alloys - a, b); structure of Ti51Ni44Cu5 surface layer - c); quantitative analysis of the grain size in Ti51Ni44Cu5 layer structure - d); X-ray – e); the content of pores in the coating – f).
Equipment for Technology One of the effective ways to form layered nanostructure composition using shape memory materials on the engineering products is a high-velocity oxygen-fuel spraying (HVOF), which has a number of advantages: a high deposition rate, coating of large items, increased adhesion properties.
The proposed technical solutions are protected by patents of the Russian Federation (patent number № 2475567, № 2502829, № 2402628) and awarded with the Gold Medal of the International Salon of Inventions and Innovation Technologies "Archimedes-2014", with the Bronze Medal of the International Exhibition of Inventions "Concours Lepine - 2014", Paris, France.
Fig. 3 shows the effect of HVOF parameters on the adhesion strength with the substrate of the formed TiNiCu surface layers (Fig. 3a, b.) and on the characteristics of the surface layer quality: the grain size and porosity (Fig. 3, c, d).
a) b) c) d) e) f) Fig. 3 Effect of high-velocity oxygen-fuel spraying parameters on the properties of the surface layers made of shape memory alloys - a, b); structure of Ti51Ni44Cu5 surface layer - c); quantitative analysis of the grain size in Ti51Ni44Cu5 layer structure - d); X-ray – e); the content of pores in the coating – f).
Online since: July 2008
Authors: Ren Ke Kang, Zhu Ji Jin, Ze Wei Yuan, B.X. Dong
However, the columnar growth of CVD diamond results in a
polycrystalline nature and the grain sizes increase with film thickness.
The 1.4cm-1 shift to a higher wave number indicates a compressive residual stress on the PCD specimen, because the Raman band of diamond moves to higher wave number shifts with increasing applied pressure. 400 600 800 1000 1200 1400 1600 1800 2000 2200 0 10000 20000 30000 40000 1333.4 Intensity (a.u.)
It was found that the original pyramidal crystallites diminished, numerous deepening pits overspread from the protuberant faces to the grain boundaries.
The 2.63cm-1 shift to a lower wave number indicated a tensile stress on the diamond. 1597.9cm -1 was characterized as graphite band.
The 1.4cm-1 shift to a higher wave number indicates a compressive residual stress on the PCD specimen, because the Raman band of diamond moves to higher wave number shifts with increasing applied pressure. 400 600 800 1000 1200 1400 1600 1800 2000 2200 0 10000 20000 30000 40000 1333.4 Intensity (a.u.)
It was found that the original pyramidal crystallites diminished, numerous deepening pits overspread from the protuberant faces to the grain boundaries.
The 2.63cm-1 shift to a lower wave number indicated a tensile stress on the diamond. 1597.9cm -1 was characterized as graphite band.
Online since: November 2005
Authors: Ki Tae Kim, Cheol Ho Lim, Young Sup Lee, C.H. Lee, Yong Hwan Kim, Dong Choul Cho
With increasing the fraction
of small powders, the number and size of the pores decreased because small powders filled up the
pores between large powders.
To investigate the preferred orientation of grains, XRD analyses are carried out and then the results illustrated Fig. 2.
As the fraction of the small powder increased, small powders filled up the pores and then the number and size of the pores decreased and improved the bonding between powders.
However, the increase of the electrical resistivity at above PL:PS=80:20 could be explained that the carrier mobility decreased due to the the random orientation of powders and carrier scattering by grain boundaries.
The thermal conductivity κ is composed of the electronic thermal conductivity κel and phonon thermal conductivity κph: κ = κel + κph κel is related to electrical conductivity σ by the Wiedemann-Franz law: κel = L0σT = L0T / ρ where L0 is the Lorenz number.
To investigate the preferred orientation of grains, XRD analyses are carried out and then the results illustrated Fig. 2.
As the fraction of the small powder increased, small powders filled up the pores and then the number and size of the pores decreased and improved the bonding between powders.
However, the increase of the electrical resistivity at above PL:PS=80:20 could be explained that the carrier mobility decreased due to the the random orientation of powders and carrier scattering by grain boundaries.
The thermal conductivity κ is composed of the electronic thermal conductivity κel and phonon thermal conductivity κph: κ = κel + κph κel is related to electrical conductivity σ by the Wiedemann-Franz law: κel = L0σT = L0T / ρ where L0 is the Lorenz number.
Online since: October 2011
Authors: Wan Shan Wang, Peng Guan, Ji Qiang Li, Shuang Zhu, Tian Biao Yu
Main Contents of Grinding Process Simulation
As a complex physical process, grinding process is subject to a number of input factors and produces a variety of physical and mechanical phenomena.
Suto and Sata [2, 3] by measuring the number of effective abrasive and wear area to get the grinding wheel topography.
Hegeman [6] found the shape of abrasive grains was more closely resemble the shape of ellipsoid rather than spherical by SEM photographs.
The results show that the algorithm using coupled FEM and SPH can simulate the deformation of any material cutting layer, while avoiding a large number of SPH particle calculation of time-consuming.
Klocke given a model for single grain scratching on 1st European Conference on grinding in 2003, shown as in Fig.8.Yu Siyuan, Lin Bin and Han Xuesong [23, 24] studied a single crystal silicon ultra-precision grinding of molecular dynamics computer simulation.
Suto and Sata [2, 3] by measuring the number of effective abrasive and wear area to get the grinding wheel topography.
Hegeman [6] found the shape of abrasive grains was more closely resemble the shape of ellipsoid rather than spherical by SEM photographs.
The results show that the algorithm using coupled FEM and SPH can simulate the deformation of any material cutting layer, while avoiding a large number of SPH particle calculation of time-consuming.
Klocke given a model for single grain scratching on 1st European Conference on grinding in 2003, shown as in Fig.8.Yu Siyuan, Lin Bin and Han Xuesong [23, 24] studied a single crystal silicon ultra-precision grinding of molecular dynamics computer simulation.
Online since: August 2013
Authors: Yu Liu, Yi Xiao
The information store the random number and ant’s 8 direction pheromone around order by column.
The random number also has the function of a flag to indicate whether the ant needs the next location information.
Algorithm data structure Every GPU thread based on the thread number corresponds to an ant space.
Threads based on the random number determine the next location of the moving and write to the corresponding positions in Result matrix.
A fine-grained parallel GPU accelerated ant colony algorithm [J].
The random number also has the function of a flag to indicate whether the ant needs the next location information.
Algorithm data structure Every GPU thread based on the thread number corresponds to an ant space.
Threads based on the random number determine the next location of the moving and write to the corresponding positions in Result matrix.
A fine-grained parallel GPU accelerated ant colony algorithm [J].
Online since: February 2014
Authors: Ping Yang, Li Liu, Jin Chao Yang, Mian Li Cao, Wei Xia Zhao
A large number of micro-glass beads in it can reduce the friction between cement particles as ball bearing.
Thus the density difference between components of mixture is reduced and the sedimentation rate of grain will be greatly slowed down.
Table4 Mix proportions of lightweight aggregate concrete kg No Cement Fly ash Expanded perlite Expanding agent Water reducing agent W/C A1 400 450 150 40 8.5 0.7 A2 350 500 150 35 8.5 0.6 A3 300 550 150 30 8.5 0.5 A4 300 550 150 85 8.5 0.5 A5 300 550 150 85 8.5 0.55 Table5 Properties of lightweight aggregate concrete No Initial /h Final /h Bulk density /(g/cm3) viscosity Segregation Workability Bleeding Compressive Strength/MPa A1 2.9 9.6 1.32 better light Common light - A2 3.6 11.0 1.33 better light Common light - A3 4.5 10.4 1.31 best light better light 6.5 A4 4.1 12.1 1.34 best better Common no 6.6 A5 5.2 13.2 1.33 best better better no 6.9 Adding air entraining admixture and prewetted treatment.The proper amount of air entraining admixture can introduce a large number of tiny closed bubbles distributing evenly and stably in concrete structures gap.
Fig.1 shows pores are few and uneven, mostly penetrating in the reference of light aggregate concrete while a large number of unconnected spherical pores distribute evenly in this material, thus the bleeding channels are reduced and the collapse and segregation are effectively controlled in concrete.
(2)The addition of air entraining admixture can introduce a large number of tiny closed bubbles distributing evenly and stably in concrete structures gap, which reduces bleeding channels and the collapse causing by bleeding
Thus the density difference between components of mixture is reduced and the sedimentation rate of grain will be greatly slowed down.
Table4 Mix proportions of lightweight aggregate concrete kg No Cement Fly ash Expanded perlite Expanding agent Water reducing agent W/C A1 400 450 150 40 8.5 0.7 A2 350 500 150 35 8.5 0.6 A3 300 550 150 30 8.5 0.5 A4 300 550 150 85 8.5 0.5 A5 300 550 150 85 8.5 0.55 Table5 Properties of lightweight aggregate concrete No Initial /h Final /h Bulk density /(g/cm3) viscosity Segregation Workability Bleeding Compressive Strength/MPa A1 2.9 9.6 1.32 better light Common light - A2 3.6 11.0 1.33 better light Common light - A3 4.5 10.4 1.31 best light better light 6.5 A4 4.1 12.1 1.34 best better Common no 6.6 A5 5.2 13.2 1.33 best better better no 6.9 Adding air entraining admixture and prewetted treatment.The proper amount of air entraining admixture can introduce a large number of tiny closed bubbles distributing evenly and stably in concrete structures gap.
Fig.1 shows pores are few and uneven, mostly penetrating in the reference of light aggregate concrete while a large number of unconnected spherical pores distribute evenly in this material, thus the bleeding channels are reduced and the collapse and segregation are effectively controlled in concrete.
(2)The addition of air entraining admixture can introduce a large number of tiny closed bubbles distributing evenly and stably in concrete structures gap, which reduces bleeding channels and the collapse causing by bleeding
Online since: July 2014
Authors: Yuan Sheng Lou, Xiao Feng Chen, Dong Mei Hu
We assume that the system has some NameNodes whose number is p.
The basic unit of metadata hash is DHU, so it is a coarse-grained mapping.
The maximum number of metadata in the client cache was set to 1500.
The number of clients was changed to test the performance of the system under different loads.
In the condition of single NameNode, the more of clients’ number was, the higher the average latency would be, and the average latency of the improved scheme was far lower than in other two conditions.
The basic unit of metadata hash is DHU, so it is a coarse-grained mapping.
The maximum number of metadata in the client cache was set to 1500.
The number of clients was changed to test the performance of the system under different loads.
In the condition of single NameNode, the more of clients’ number was, the higher the average latency would be, and the average latency of the improved scheme was far lower than in other two conditions.
Online since: July 2015
Authors: Shun Xiang Sun, Hao Yu Zhao, Shu Bai Li
A number of functional nanofibers and composites have been developed through electrospinning by incorporating well-selected functional agents to achieve antibacterial properties.
FA is also found esterified to phytosterols present in grain products such as rice bran.
Antibacterial Activity.Antibacterial efficacy of surface modified nonwoven containing FA was investigated by estimating the number of viable bacteria cells in the S. aureus and E. coli suspension after being in contact with nonwoven for various periods of time, and the results were shown in Fig. 3.
Viable cell numbers of Staphylococcus aureus and Escherichia coli as a function time in contact with: nonwoven.
The cell number was determined by surface spread plate method.
FA is also found esterified to phytosterols present in grain products such as rice bran.
Antibacterial Activity.Antibacterial efficacy of surface modified nonwoven containing FA was investigated by estimating the number of viable bacteria cells in the S. aureus and E. coli suspension after being in contact with nonwoven for various periods of time, and the results were shown in Fig. 3.
Viable cell numbers of Staphylococcus aureus and Escherichia coli as a function time in contact with: nonwoven.
The cell number was determined by surface spread plate method.