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Online since: January 2006
Authors: Dominique Mangelinck
EDS results shows that Ge is rejected
from the NiSi1-uGeu grains to a thin shell of SiGe
around the NiSi1-uGeu grains.
Above 600°C, a migration of the NiSi1-uGeu grains inside SiGe occurs together with some diffusion of Ge from the NiSi1-uGeu grains in SiGe.
It should be noted that while the EDS results represent individual grains and give local atomic composition information, the XRD results are averaged over a large number of grains.
Several samples were studied in order to increase the number of reacting interfaces.
Does it mean that there is no actual energetic barrier, but some problems with pre-exponential factor (limited number of sites for interphase transitions etc.)?
Above 600°C, a migration of the NiSi1-uGeu grains inside SiGe occurs together with some diffusion of Ge from the NiSi1-uGeu grains in SiGe.
It should be noted that while the EDS results represent individual grains and give local atomic composition information, the XRD results are averaged over a large number of grains.
Several samples were studied in order to increase the number of reacting interfaces.
Does it mean that there is no actual energetic barrier, but some problems with pre-exponential factor (limited number of sites for interphase transitions etc.)?
Online since: November 2014
Authors: Hai Wen Teng, Yu Chuan Jiang, Da Huo, Jin E Xu
In addition, the date [9] described the grain composition system with higher bulk density by Fuller-Thompson-Andreasson equation.
Some scholars considered the influence of aggregate grain form on the accumulation system and presented fuller curve elliptic equation.
Aggregate grain dispersed in the slurry with a certain distance, and concrete with different spacing of aggregate according to two different volume contents.
The ratio of the total length of coarse aggregate throughing every line and the total number of coarse aggregates is the average diameter (D) throughing every line.
And the ratio of the total spacing and the total number of coarse aggregates is the average spacing (d) of the surface of adjacent coarse aggregates.
Some scholars considered the influence of aggregate grain form on the accumulation system and presented fuller curve elliptic equation.
Aggregate grain dispersed in the slurry with a certain distance, and concrete with different spacing of aggregate according to two different volume contents.
The ratio of the total length of coarse aggregate throughing every line and the total number of coarse aggregates is the average diameter (D) throughing every line.
And the ratio of the total spacing and the total number of coarse aggregates is the average spacing (d) of the surface of adjacent coarse aggregates.
Online since: April 2013
Authors: Tahseen H. Mubarak, Karim H. Hassan, Zena Mohammed Ali Abbas
SEM micrographs reveals less number of pores with smaller lump size in addition to clearly showing the micro structural homogeneity and remarkably dense mode of packing of grains of ZnO nanoparticles with minimum porosity.
Also SEM micrographs reveals less number of pores with smaller lump size in addition to clearly showing the micro structural homogeneity and remarkably dense mode of packing of grains of ZnO nanoparticles with minimum porosity.
Also SEM micrographs reveals less number of pores with smaller lump size in addition to clearly showing the micro structural homogeneity and remarkably dense mode of packing of grains of ZnO nanoparticles with minimum porosity.
Online since: October 2018
Authors: Andrey Ponomarev, Vadim Golozubenko, Yuriy Sivkov, Kirill Galinskij, Vadim Aleksandrov
YUV1 horizon of the Ershovoye field is represented by fine-grained quartz sandstones and coarse-grained siltstones, their calcareous varieties that are interbedded with kaolinite mud, limestone, and beds of hard coal.
In a number of wells (southwestern part of the field), sandy-aleuritic interstratified beds (formations) converge, forming monolithic bodies, which determine the hydrodynamic connectivity among all parts of the section.
The YUS11 formation of the Kinyaminskoye field is represented by an alternation of polymictic medium- and fine-grained sandstones with kaolinite or dickite cement and large-fine-grained siltstones of quartz-feldspar composition.
The YUS11 horizon of the Vostochno-Surgutskoye field is represented by the alternation of mudstones, siltstones, and fine-grained sandstones with beds of argillite-like mud with inclusions of coal interbeds.
In general, the effect of the MPDC application at the site was expressed in the stabilization of water-cut and the decrease in oil production, and a number of individual oil wells were marked with the increase in oil production rates (Fig. 3).
In a number of wells (southwestern part of the field), sandy-aleuritic interstratified beds (formations) converge, forming monolithic bodies, which determine the hydrodynamic connectivity among all parts of the section.
The YUS11 formation of the Kinyaminskoye field is represented by an alternation of polymictic medium- and fine-grained sandstones with kaolinite or dickite cement and large-fine-grained siltstones of quartz-feldspar composition.
The YUS11 horizon of the Vostochno-Surgutskoye field is represented by the alternation of mudstones, siltstones, and fine-grained sandstones with beds of argillite-like mud with inclusions of coal interbeds.
In general, the effect of the MPDC application at the site was expressed in the stabilization of water-cut and the decrease in oil production, and a number of individual oil wells were marked with the increase in oil production rates (Fig. 3).
Online since: July 2022
Authors: Xiao Nan Dai, Wei Chun He, Ling Bai, Xue Zhou, Zheng Xin Li
Force analysis of abrasive grains during sand loading.
In a high gradient magnetic field, the magnetic force Fn acting on the magnetic abrasive grains can be expressed as: Fn=2πrp3μ0μrKVp∇H2, K=μr,p-μrμr,p+2μr
The Reynolds number of the bath is low, and it is in Stokes law region[9, 10].
S-3400 scanning electron microscope was used to observe the surface morphology of diamond abrasive grains with different weight gain rates and the wire saw made from them.
The number of abrasive grains deposited on diamond wire saw per unit area (1 mm surface area) was observed by hand-held digital microscope.
In a high gradient magnetic field, the magnetic force Fn acting on the magnetic abrasive grains can be expressed as: Fn=2πrp3μ0μrKVp∇H2, K=μr,p-μrμr,p+2μr
The Reynolds number of the bath is low, and it is in Stokes law region[9, 10].
S-3400 scanning electron microscope was used to observe the surface morphology of diamond abrasive grains with different weight gain rates and the wire saw made from them.
The number of abrasive grains deposited on diamond wire saw per unit area (1 mm surface area) was observed by hand-held digital microscope.
Online since: September 2020
Authors: Jia Xin Sun, Xin Gu, Bing Qin Zhou
At a certain pressure, when the RF power is changed, the average grain size in the films decrease by XRD analysis.
With increased power, NH3 and N2 also increased, and enhancement of Si-H bonds indicated that the number of H atoms melting into the film increased, which could have played a good passivation role on the film.
The average grain size was calculated using Debye-Scherrer [9] formula, expressed as
From calculations, the film grain sizes were found to be on the order of nanometers and gradually reduced.
It was found that Si3N4 crystalline grains appeared in the films, and the size of the crystalline grains decreased gradually with increasing power.
With increased power, NH3 and N2 also increased, and enhancement of Si-H bonds indicated that the number of H atoms melting into the film increased, which could have played a good passivation role on the film.
The average grain size was calculated using Debye-Scherrer [9] formula, expressed as
From calculations, the film grain sizes were found to be on the order of nanometers and gradually reduced.
It was found that Si3N4 crystalline grains appeared in the films, and the size of the crystalline grains decreased gradually with increasing power.
Online since: January 2009
Authors: Berend Denkena, Luis de Leon, B. Wang, Dennis Hahmann
To assure small form and
dimensional tolerances over an adequate number of workpieces, the grinding wheels have to be
regularly redressed.
When the voltage increases, the number of suitable particles and thus the probability of discharge increase.
According to the results of the last studies on form dressing [10], a fine grained vitrified bonded SiC-wheel with an average grain size of 17 µm and an outer diameter of 300 mm was selected at the beginning.
The SiC grains and the pores are distributed uniformly troughout the bond.
At the CBN wheel, the grains build many clusters which are fully surrounded by the bond material.
When the voltage increases, the number of suitable particles and thus the probability of discharge increase.
According to the results of the last studies on form dressing [10], a fine grained vitrified bonded SiC-wheel with an average grain size of 17 µm and an outer diameter of 300 mm was selected at the beginning.
The SiC grains and the pores are distributed uniformly troughout the bond.
At the CBN wheel, the grains build many clusters which are fully surrounded by the bond material.
Online since: November 2013
Authors: Guo Xing Zhang, Yun Song Hua, Yan Wen Shen, Hong Wu Yang
DPSM analysis reveals that the ultrasonic field of certain strength can be formed in the thick steel specimen of coarse grain, and the focused transducer of 15MHz is suitable for the inclusion evaluation of thick steel specimens.
The relationship of frequency, diameter, focal length, and eradiating fluid parameters, and radius of a concave spherical surface is described as follow, (1) (2) Z: the distance from transducer surface along axis direction; k: Wave numbers; a: Radius of transducer; R: The radius of a concave spherical surface; r: Density of fluid; c: The ultrasonic speed in fluid; u: Surface vibration speed of transducer; The parameters used in simulation are as following: the steel density is 7850kg/m3, ultrasonic speed in steel is 6000m/s, the grain size is 4mm, the density of grain boundary is 3925kg/m3, ultrasonic speed in grain boundary is 3000m/s, its thickness is 10 mm.
It is obvious that the ultrasonic energy of above frequencies can be focalized in the coarse-grain steel model coupled by water.
By normalizing treatment, the specimen texture is of the tiny ferrite and pearlite, the grain size of which is less than 100mm.
Summary DPSM analysis reveals that the ultrasonic field of certain strength can be formed in the thick steel specimen of coarse grain, and the focused transducer of 15MHz is suitable for the inclusion evaluation of thick steel specimens.
The relationship of frequency, diameter, focal length, and eradiating fluid parameters, and radius of a concave spherical surface is described as follow, (1) (2) Z: the distance from transducer surface along axis direction; k: Wave numbers; a: Radius of transducer; R: The radius of a concave spherical surface; r: Density of fluid; c: The ultrasonic speed in fluid; u: Surface vibration speed of transducer; The parameters used in simulation are as following: the steel density is 7850kg/m3, ultrasonic speed in steel is 6000m/s, the grain size is 4mm, the density of grain boundary is 3925kg/m3, ultrasonic speed in grain boundary is 3000m/s, its thickness is 10 mm.
It is obvious that the ultrasonic energy of above frequencies can be focalized in the coarse-grain steel model coupled by water.
By normalizing treatment, the specimen texture is of the tiny ferrite and pearlite, the grain size of which is less than 100mm.
Summary DPSM analysis reveals that the ultrasonic field of certain strength can be formed in the thick steel specimen of coarse grain, and the focused transducer of 15MHz is suitable for the inclusion evaluation of thick steel specimens.
Online since: March 2014
Authors: Pavol Hvizdoš, Ján Dusza, Annamária Duszová, Tamás Csanádi, Marek Bľanda
The room temperature elastic and plastic properties of the tungsten-carbide grains of WC-9%Co hardmetal were investigated by nanoindentation and atomic force microscope (AFM).
Even though a number of experimental and theoretical studies have been carried out on WC-Co cemented carbides [6,8-10], these measurements could have given an account of only the common effect of the deformation of WC particles and the cobalt binder during microindentation.
These results are inconsistent with the earlier studies [2-5] and with some recent papers [12,13] on WC single crystals grains.
The present paper addresses this problem in order to reveal the real anisotropic behavior of elastic and plastic deformation induced by nanoindentation in a wide range of depth on basal and prismatic facets of WC grains.
Experimental material and procedure In this paper, tungsten carbide-cobalt composite material was investigated containing 9% volume fraction of cobalt (WC-9Co) and the grain size was in the interval 3-25 µm.
Even though a number of experimental and theoretical studies have been carried out on WC-Co cemented carbides [6,8-10], these measurements could have given an account of only the common effect of the deformation of WC particles and the cobalt binder during microindentation.
These results are inconsistent with the earlier studies [2-5] and with some recent papers [12,13] on WC single crystals grains.
The present paper addresses this problem in order to reveal the real anisotropic behavior of elastic and plastic deformation induced by nanoindentation in a wide range of depth on basal and prismatic facets of WC grains.
Experimental material and procedure In this paper, tungsten carbide-cobalt composite material was investigated containing 9% volume fraction of cobalt (WC-9Co) and the grain size was in the interval 3-25 µm.
Online since: August 2012
Authors: Wolfgang Limberg, Michael Oehring, Frank Peter Schimansky, Thomas Ebel, Florian Pyczak, Orley Milagres Ferri
Therefore the grain growth is not hindered by the presence of a second phase and a rather large grain size compared to wrought material is a characteristic of MIM material.
If the grain size of MIM material has to be significantly reduced, it is necessary to use grain refiners as it will be shown below.
Indeed, experience shows that the pick-up of oxygen is more depending on the number of sinter parts in the furnace than on temperature.
During sintering in the beta region the growth of the beta grains is impeded by grain boundary pinning by these titanium boride particles.
This leads to more and smaller alpha grains.
If the grain size of MIM material has to be significantly reduced, it is necessary to use grain refiners as it will be shown below.
Indeed, experience shows that the pick-up of oxygen is more depending on the number of sinter parts in the furnace than on temperature.
During sintering in the beta region the growth of the beta grains is impeded by grain boundary pinning by these titanium boride particles.
This leads to more and smaller alpha grains.