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Online since: July 2011
Authors: Yi Qing Lv, Hong Fu Liu, Xue Qin Wen
In the center there were gray green, green, apricot, gray fine-grained sandstone, purple sandy mudstone Interbedded with mudstone and sandstones were among it .
In the bottom there were Coarse-grained sandstone of the purple, or conglomerate.
In the upper the purple layer of thick fine-grained quartz feldspar sandstone interbeded with brick-red sandy mudstone and siltstone.
In the study area mining, quarry spoil and garbage piled up a lot, also formed a large number of deposits with completely loose state .They were easily taken away by a flood, which provided a rich source for the formation of debris flow.
Water that carrying a large number of sediment (solid substances) concentrated migration formed mudslides.
In the bottom there were Coarse-grained sandstone of the purple, or conglomerate.
In the upper the purple layer of thick fine-grained quartz feldspar sandstone interbeded with brick-red sandy mudstone and siltstone.
In the study area mining, quarry spoil and garbage piled up a lot, also formed a large number of deposits with completely loose state .They were easily taken away by a flood, which provided a rich source for the formation of debris flow.
Water that carrying a large number of sediment (solid substances) concentrated migration formed mudslides.
Online since: December 2011
Authors: Jian Bin Xin, Yu Zhong Yang
FESEM images and EDS analyses showed that TiC spherical grains constituted the matrix of the TiC-TiB2, and a number of TiB2 platelets were embedded in the TiC matrix, whereas a few of white (Cr,W,Ti)3B2 phases were distributed in between TiC spherical grains and TiB2 platelets.
It is considered high hardness of TiC-TiB2 benefited from the achievement of fine-grained microstructure and near full density, as shown in Fig. 6, while high fracture toughness of ceramics is attributed to crack deflection, crack-bridging and pull-up of small-size hard TiB2 platelets, as shown in Fig. 7 and Fig. 8.
Meanwhile, the high bending strength of TiC-TiB2 composite benefited from the fined-grained microstructure, high fracture toughness and small-size defect of the ceramics.
XRD, FESEM and EDS analyses showed that TiC spherical grains constituted the matrix of the TiC-TiB2, and within TiC grains a number of TiB2 platelets were embedded.
It is considered high hardness of TiC-TiB2 benefited from the achievement of fine-grained microstructure and near full density, as shown in Fig. 6, while high fracture toughness of ceramics is attributed to crack deflection, crack-bridging and pull-up of small-size hard TiB2 platelets, as shown in Fig. 7 and Fig. 8.
Meanwhile, the high bending strength of TiC-TiB2 composite benefited from the fined-grained microstructure, high fracture toughness and small-size defect of the ceramics.
XRD, FESEM and EDS analyses showed that TiC spherical grains constituted the matrix of the TiC-TiB2, and within TiC grains a number of TiB2 platelets were embedded.
Online since: October 2014
Authors: Yong Li, Chao Xu, Shuai Yin, Pei Wang, Jian Lai Zou, Zi Li Kou
(A)) with a average grain size of 30 um was used as starting materials based on the experiment conclusion that large grain size is beneficial to impact resistance .The WC-Co substrate approximately contained 20wt% Co with WC grains of 3~5um and the substrate’s top surface with irregularities in the form of annular grooves is shown in Fig.1.
Fig.3.Perspective view of well-sintered sample synthesized at 5.5 Gpa /1450℃ with average grain size 30um, holding for 3 min.
The presence of graphite phase may due to the long sintering time for large grain size.
Overall, the diamond grains uniformly disperse throughout the cobalt phase and the image shows a substantially homogeneous sintered dense microstructure with inter-granular diamond growth.
With this assumption, and considering that Raman peak splitting was not observed, the stress in the PCD layer surface can be written as [11] : (1) Whereis the residual biaxial stress, is the unstressed diamond wave-number (1332cm-1), and is the measured wave-number of the diamond on the PCD layer surface.
Fig.3.Perspective view of well-sintered sample synthesized at 5.5 Gpa /1450℃ with average grain size 30um, holding for 3 min.
The presence of graphite phase may due to the long sintering time for large grain size.
Overall, the diamond grains uniformly disperse throughout the cobalt phase and the image shows a substantially homogeneous sintered dense microstructure with inter-granular diamond growth.
With this assumption, and considering that Raman peak splitting was not observed, the stress in the PCD layer surface can be written as [11] : (1) Whereis the residual biaxial stress, is the unstressed diamond wave-number (1332cm-1), and is the measured wave-number of the diamond on the PCD layer surface.
Online since: June 2014
Authors: Ji Shan Zhang, Long Gang Hou, Cun Qiang Ma, Lin Zhong Zhuang
Also with increasing pass number, the center regions of the sheets can be subjected to higher shear stress and the deformation is increased correspondingly.
Yao, Shear deformation and grain refinement in pure al by asymmetric rolling, Trans.
Shan, Mechanical properties and microstructures of ultrafine-grained pure aluminum by asymmetric rolling, Scripta Mater. 60(2009) 905-908
Minamino, Strength and ductility of ultrafine grained aluminum and iron produced by ARB and annealing, Scripta Mater. 47(2002) 893-899
Ohori, Grain refinement of high purity aluminum by asymmetric rolling, Mater.
Yao, Shear deformation and grain refinement in pure al by asymmetric rolling, Trans.
Shan, Mechanical properties and microstructures of ultrafine-grained pure aluminum by asymmetric rolling, Scripta Mater. 60(2009) 905-908
Minamino, Strength and ductility of ultrafine grained aluminum and iron produced by ARB and annealing, Scripta Mater. 47(2002) 893-899
Ohori, Grain refinement of high purity aluminum by asymmetric rolling, Mater.
Online since: April 2013
Authors: Oksana Chukova, Sergiy G. Nedilko, Sergiy A. Nedilko, Vasyl Sherbatsky, Tetiana Voitenko
Thus, it is possible to get material with powder grains of smaller sizes (about several hundreds of nanometers) applying co-precipitation procedure of synthesis.
The 5D0 level is singlet, therefore a number of emission lines those can be observed in the ranges corresponded to certain J (J – range) is defined by J value and local symmetry of the Eu3+ ions.
A number of lines has to be maximal for low symmetry of the Eu3+ surrounding (it is monoclinic LaVO4).
As it is mentioned above, sizes of the powder grains is essentially smaller for the samples obtained by the co-precipitation method that is why in this case we should expect size effects caused by raise of ratio between surface of grains and their volume at decreasing of sizes of particles.
SEM microscopy data has shown that, average grain sizes of powders obtained by co-precipitation synthesis are in four times smaller than average grain sizes of powders obtained by solid state synthesis.
The 5D0 level is singlet, therefore a number of emission lines those can be observed in the ranges corresponded to certain J (J – range) is defined by J value and local symmetry of the Eu3+ ions.
A number of lines has to be maximal for low symmetry of the Eu3+ surrounding (it is monoclinic LaVO4).
As it is mentioned above, sizes of the powder grains is essentially smaller for the samples obtained by the co-precipitation method that is why in this case we should expect size effects caused by raise of ratio between surface of grains and their volume at decreasing of sizes of particles.
SEM microscopy data has shown that, average grain sizes of powders obtained by co-precipitation synthesis are in four times smaller than average grain sizes of powders obtained by solid state synthesis.
Online since: August 2012
Authors: Dong Liang Zhao, Zhong Hui Hou, Xiao Gang Liu, Le Le Chen, Yang Huan Zhang, Guo Fang Zhang
It can be seen that both of the melt spinning and the Zr substitution give rise to the major diffraction peaks of the alloys obviously broadened, to be ascribed to the refined grain and the stored stress in the grains by the melt spinning.
The evolution of the capacity retaining rates (Rn) of the as-spun alloys with the cycle number is presented in Fig. 3.
The increased cycle stability of the as-cast alloys originated from substituting La with Zr is basically attribute to the refined grains resulted from such substitution.
The benefaction of the melt spinning on the cycle stability of the alloy is primarily ascribed to the remarkable refinement of the grains and the formation of an amorphous phase induced by the melt spinning.
The anti-pulverization capability of the alloy basically depends on its grain size.
The evolution of the capacity retaining rates (Rn) of the as-spun alloys with the cycle number is presented in Fig. 3.
The increased cycle stability of the as-cast alloys originated from substituting La with Zr is basically attribute to the refined grains resulted from such substitution.
The benefaction of the melt spinning on the cycle stability of the alloy is primarily ascribed to the remarkable refinement of the grains and the formation of an amorphous phase induced by the melt spinning.
The anti-pulverization capability of the alloy basically depends on its grain size.
Online since: October 2010
Authors: Wei Zhang, Chao Ping Zhang, De Jun Shen
to Co2+ (dCo2+…74:5 pm); so speculate that Cu2+ could replace Co2+ entering the cubic structure of Co3O4 (maybe forming CuxCo3-xO4 solid solution with the spinel structure).The maximum number of Cu2+accommodated by CuxCo3-x O4 with spinel structure was at Co/Cu ratio of 2/1, where Co2+ in Co3O4 was totally replaced by Cu2+.
Fig.3 suggested the average and Co3O4 (111),CuO(110) grain diameter are lesser as burned at 500°C.The SAED pattern of the composite oxides carried out on one single particle showed diffraction rings with spots superimposed (Fig. 2B), which was suggested that the formed ultra-micro particles are polycrystalline.
The values obtained can reasonably be associated with a nucleation and grain growth process as in the cases of the Co-based and Ni-based nanoparticles [14,25].
Likely, at the beginning of sintering, a small grain size and poor homogeneity of Co-Cu composite, besides the presence of metal nitrides were observed; while at higher temperatures and upon increasing the sintering time, grain growth and Co-Cu inner diffusion are responsible for the decrease of χm.
The grains formed initially grow depends on the annealed temperatures, indicating a large number of equally sized pine needle shape grains are observed in individual clusters.
Fig.3 suggested the average and Co3O4 (111),CuO(110) grain diameter are lesser as burned at 500°C.The SAED pattern of the composite oxides carried out on one single particle showed diffraction rings with spots superimposed (Fig. 2B), which was suggested that the formed ultra-micro particles are polycrystalline.
The values obtained can reasonably be associated with a nucleation and grain growth process as in the cases of the Co-based and Ni-based nanoparticles [14,25].
Likely, at the beginning of sintering, a small grain size and poor homogeneity of Co-Cu composite, besides the presence of metal nitrides were observed; while at higher temperatures and upon increasing the sintering time, grain growth and Co-Cu inner diffusion are responsible for the decrease of χm.
The grains formed initially grow depends on the annealed temperatures, indicating a large number of equally sized pine needle shape grains are observed in individual clusters.
Online since: February 2012
Authors: Jin Song Yang, Rui Yang, Hai Sheng Tan
Effect of wall material types on inclusion rates was shown in Table 2. β-cyclodextrin + gelatin could reach the highest 72.78%, and furthermore, it was even grain with light pink.
Table 2 Effect of wall material types on inclusion rates Wall materials Appearance of its product Inclusion rate Gelatin Uneven grain, light pink 60.12% β-cyclodextrin Even grain, light pink 70.45% β-cyclodextrin + sucrose Even grain, light pink 70.26% β-cyclodextrin + gelatin Even grain, light pink 72.78% β-cyclodextrin + sucrose + gelatin Uneven grain, light pink 67.45% 2.
Table 3 Experimental design and results of response surface design Experiment numbers Inclusion temperature (˚C) Wall material quantity(g/g yeast) Time (h) Inclusion rate(%) 1 30 0.4 2 75.80 2 50 0.4 2 74.65 3 30 0.6 2 69.98 4 50 0.6 2 73.18 5 30 0.5 1 72.17 6 50 0.5 1 73.78 7 30 0.5 3 74.28 8 50 0.5 3 72.87 9 40 0.4 1 80.60 10 40 0.6 1 73.93 11 40 0.4 3 75.74 12 40 0.6 3 76.48 13 40 0.5 2 78.70 14 40 0.5 2 79.60 15 40 0.5 2 78.93 Minitab 15 was used to perform statistic analysis on data in Table 3 and establish response surface regression model and get the best response factor level.
Fig. 9 Storage stability of inclusion complex Acknowledgements This work was supported by the Spark Program of the Ministry of Science and Technology of the People's Republic of China Project Number 2008GA800015, the Science Planning Project of Haikou city (Supporting national projects funded).
Table 2 Effect of wall material types on inclusion rates Wall materials Appearance of its product Inclusion rate Gelatin Uneven grain, light pink 60.12% β-cyclodextrin Even grain, light pink 70.45% β-cyclodextrin + sucrose Even grain, light pink 70.26% β-cyclodextrin + gelatin Even grain, light pink 72.78% β-cyclodextrin + sucrose + gelatin Uneven grain, light pink 67.45% 2.
Table 3 Experimental design and results of response surface design Experiment numbers Inclusion temperature (˚C) Wall material quantity(g/g yeast) Time (h) Inclusion rate(%) 1 30 0.4 2 75.80 2 50 0.4 2 74.65 3 30 0.6 2 69.98 4 50 0.6 2 73.18 5 30 0.5 1 72.17 6 50 0.5 1 73.78 7 30 0.5 3 74.28 8 50 0.5 3 72.87 9 40 0.4 1 80.60 10 40 0.6 1 73.93 11 40 0.4 3 75.74 12 40 0.6 3 76.48 13 40 0.5 2 78.70 14 40 0.5 2 79.60 15 40 0.5 2 78.93 Minitab 15 was used to perform statistic analysis on data in Table 3 and establish response surface regression model and get the best response factor level.
Fig. 9 Storage stability of inclusion complex Acknowledgements This work was supported by the Spark Program of the Ministry of Science and Technology of the People's Republic of China Project Number 2008GA800015, the Science Planning Project of Haikou city (Supporting national projects funded).
Online since: October 2014
Authors: Suphan Yangyuen, Songchai Wiriyaumpaiwong, Juckamas Laohavanich, Cherpong Chaiwchanwattana
The different principles of operation by streak belt consist of number of strips and its configurations: full swath section, 4 – 5 zigzag and 4 eccentric drums.
On contrary, it is probably proper for cereal grain with pericarp.
First of all, in shelling operation, sunflower seed was fed into hopper where installed the manual valve to adjust grain feed rate.
Selecting of screen opening hole size considers from sphericity and major diameters of inside kernel and unshelled grain.
The unshelled grain can be not passed through holes of screen whereas the kernel passed.
On contrary, it is probably proper for cereal grain with pericarp.
First of all, in shelling operation, sunflower seed was fed into hopper where installed the manual valve to adjust grain feed rate.
Selecting of screen opening hole size considers from sphericity and major diameters of inside kernel and unshelled grain.
The unshelled grain can be not passed through holes of screen whereas the kernel passed.
Online since: December 2013
Authors: Mark P. Kalashnikov, Sergey Panin, Viktor Sergeev, Vasilii Naidfeld, Oleg Bogdanov, Boris Ovechkin, Ilya Vlasov
It is seen that in the surface layer of the specimen after the ion beam treatment, the grain structure with the average size of structural elements of 2-5 µm is revealed (Fig. 4, b,d).
Additionally, by the optical micrographs of the cross section the characteristic depth of the layer with ferrite grains to form during the irradiation was estimated.
It is shown that the average depth where ferrite grains become distinguishable makes 35±4 µn (Fig. 4,d).
During the fatigue tests the average number of cycles prior the fracture were determined.
The dependence graph of the fatigue crack length vs the number of loading cycles was built being based on analysis of the surface image captured during the tests (Fig. 2,b).
Additionally, by the optical micrographs of the cross section the characteristic depth of the layer with ferrite grains to form during the irradiation was estimated.
It is shown that the average depth where ferrite grains become distinguishable makes 35±4 µn (Fig. 4,d).
During the fatigue tests the average number of cycles prior the fracture were determined.
The dependence graph of the fatigue crack length vs the number of loading cycles was built being based on analysis of the surface image captured during the tests (Fig. 2,b).