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Online since: February 2020
Authors: L.G. Marques, Manoel Marcelo Prado, Raí M. de Oliveira, Keyse S. Andrade
IR radiation is then recommended for drying grains in a single thin layer [4,7].
Spite of large number of works dealing with combined infrared and hot-air drying, few studies [7] are devoted to provide information on the use of IR radiation assisted by non-heated air convection, what could contribute to save energy and improve product quality.
Thus, the total number of nineteen experimental runs were required, with duplicate in the maximum and minimum variables levels and triplicate in the center point.
The finding obtained in this work is not in agreement with the finding of Brandão et al. [7] who reported a reduction in Deff-values with an increase of the non-heated air velocity in the hybrid drying of pollen grains.
Spite of large number of works dealing with combined infrared and hot-air drying, few studies [7] are devoted to provide information on the use of IR radiation assisted by non-heated air convection, what could contribute to save energy and improve product quality.
Thus, the total number of nineteen experimental runs were required, with duplicate in the maximum and minimum variables levels and triplicate in the center point.
The finding obtained in this work is not in agreement with the finding of Brandão et al. [7] who reported a reduction in Deff-values with an increase of the non-heated air velocity in the hybrid drying of pollen grains.
Online since: December 2009
Authors: Shen Yung Lin, C.C. Tang, J.C. Shih, S.S. Chi
A hardfacing with
large carbide grains showed lower cutting temperatures and exhibited lower increase rate with
cutting speed and feed rate.
The porosity, ductility and the bonding strength of the grains in the tool, apart from its thermal conductivity appear to have great influences on the fracture resistance of the tool.
These nodes evaluate the limited number of inputs by a polynomial function and generate an output to serve as an input to subsequent nodes of the next layer.
The PSE is composed of two terms; that is: PSE=FSE+KP (2) (2) where FSE is the average square error of the network for fitting the training data and KP is the complex penalty of the network, shown as the following equation: NK CPMK p p 2 2 (3) where CPM is the complex penalty multiplier, K is a coefficient of the network, N is the number of training data to be used and P 2 is a prior estimate of the model error variance. 4.
The porosity, ductility and the bonding strength of the grains in the tool, apart from its thermal conductivity appear to have great influences on the fracture resistance of the tool.
These nodes evaluate the limited number of inputs by a polynomial function and generate an output to serve as an input to subsequent nodes of the next layer.
The PSE is composed of two terms; that is: PSE=FSE+KP (2) (2) where FSE is the average square error of the network for fitting the training data and KP is the complex penalty of the network, shown as the following equation: NK CPMK p p 2 2 (3) where CPM is the complex penalty multiplier, K is a coefficient of the network, N is the number of training data to be used and P 2 is a prior estimate of the model error variance. 4.
Development of Advanced Surface Engineering Technologies for the Benefit of Multipoint Cutting Tools
Online since: December 2009
Authors: Mohammed Sarwar, Julfikar Haider
However, the performance of TiN coating in
reducing the flank wear is not always consistent showing little or no improvement in a number of
teeth.
Furthermore, reduction in friction on 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Flute number Flank wear (mm) TiN coated Uncoated W/P: M42 HSS + D6A steel Feed/tooth: 0.12 mm Speed: 65 rpm Flood cooling No. of milling passes: 600 Flank wear PM HSS milling Cutter Dia.: 160 mm Length: 152 mm 16 flutes 23 teeth/flute TiN coated tooth Uncoated tooth the face/sides of the saws reduce forces, torque etc..
For example, Powder Metallurgy (PM) HSS broach tools show improvement in quality of cutting edges and tool life over conventional HSS due to uniformly distributed fine grain carbides leading to improved toughness and strength without compromising the hardness [13].
All of these factors contribute to the growth of fine-grained and dense coating microstructure on the tool, increased coating adhesion and thickness uniformity, which lead to enhancement in machining performance.
Furthermore, reduction in friction on 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Flute number Flank wear (mm) TiN coated Uncoated W/P: M42 HSS + D6A steel Feed/tooth: 0.12 mm Speed: 65 rpm Flood cooling No. of milling passes: 600 Flank wear PM HSS milling Cutter Dia.: 160 mm Length: 152 mm 16 flutes 23 teeth/flute TiN coated tooth Uncoated tooth the face/sides of the saws reduce forces, torque etc..
For example, Powder Metallurgy (PM) HSS broach tools show improvement in quality of cutting edges and tool life over conventional HSS due to uniformly distributed fine grain carbides leading to improved toughness and strength without compromising the hardness [13].
All of these factors contribute to the growth of fine-grained and dense coating microstructure on the tool, increased coating adhesion and thickness uniformity, which lead to enhancement in machining performance.
Online since: December 2012
Authors: Yi Lian Li, Telesphore Kabera
The Corey function was used to get the relative permeability for free CO2 phase;
krg = (1-Sˆ )2(1-Sˆ 2) (3)
S^ = (Sl-Slr)/(1-Slr-Sgr) (4)
For the capillary pressure between the two phases the following equation was used:
Pcap = -P0([S*]-1/λ – 1)1-λ (5)
P0 = √(ø/k) (6)
Table 1
Aquifer Properties Used in Flow Simulations
Rock grain density (kg m-3)
2600
Aquifer horizontal distance (km)
21
Aquifer nett thickness (m)
110
Porosity (%)
15.4
Formation heat conductivity under fully liquid-saturated conditions (W/m°C)
2.51
Rock grain specific heat (J/kg°C)
920
Aquifer initial temperature (°C)
89
CO2 injection temperature (°C)
45
Aquifer initial pressure (bar)
220
CO2 injection pressure (bar)
270
Salinity (mass fraction)
0.29
Rock compressibility (Pa-1)
4.5 x 10-10
Liquid relative permeability, krl
√S*{1-(1-[S*]1/m)m}2, S* = (Sl-Slr)/(1-Slr)
Residual water saturation, Srl
0.30
Gas relative permeability, krg
(1-Sˆ )2(1-Sˆ 2), S^ = (Sl-Slr)/(1-Slr-Sgr)
Residual gas saturation
Figure 5 Gas saturation spatial distribution during CO2 sequestration (Left frames present only injection case, and the right frames represent one injection and two production case) (0.1 cut-off) Results and Discussion As it was mentioned above, while placing production wells, one has to be careful in order to prevent the risk of producing CO2, in order to achieve this, a number of simulations were performed such as placing the production well at a distance of about 7.5km from the injection, this case showed that after 200 years the CO2 mobile migrating horizontally will reach the production but when the distance was increased to about 9.5km from the injection well, even after 700 years the CO2 mobile will not reach the production well ( Figure 5).
As it is shown in figure 6 the effect of shale layers is to retard migration of CO2 mobile phase front normally depending on the number of shale layers.
Figure 5 Gas saturation spatial distribution during CO2 sequestration (Left frames present only injection case, and the right frames represent one injection and two production case) (0.1 cut-off) Results and Discussion As it was mentioned above, while placing production wells, one has to be careful in order to prevent the risk of producing CO2, in order to achieve this, a number of simulations were performed such as placing the production well at a distance of about 7.5km from the injection, this case showed that after 200 years the CO2 mobile migrating horizontally will reach the production but when the distance was increased to about 9.5km from the injection well, even after 700 years the CO2 mobile will not reach the production well ( Figure 5).
As it is shown in figure 6 the effect of shale layers is to retard migration of CO2 mobile phase front normally depending on the number of shale layers.
Online since: May 2012
Authors: Hai Dong Wu, Mei Li Zhou, Hai Fan, Ya Zhang, Tong Lou Ding, Bao Shan Wang
As a result China neither allows cultivating biomass energy plants in crop lands, nor translating crop grains into bio-fuels.
Furthermore, the number of bacteria, salt-tolerant bacteria, and actinomycetes all increased with the application of fertilizers (treatment IV=treatment III>treatment II> control), but the number of salt-tolerant actinomycetes did not change significantly.
Additional fertilizer can be applied at the shooting stage and booting stage, while leaf surface fertilizer can be applied at the grain filling stage to increase sorghum juice Brix.
Furthermore, the number of bacteria, salt-tolerant bacteria, and actinomycetes all increased with the application of fertilizers (treatment IV=treatment III>treatment II> control), but the number of salt-tolerant actinomycetes did not change significantly.
Additional fertilizer can be applied at the shooting stage and booting stage, while leaf surface fertilizer can be applied at the grain filling stage to increase sorghum juice Brix.
Online since: July 2011
Authors: Lei Wang, Xue Tao Yuan, Zhi Qiang Hua, Dong Bai Sun, Song Lin Chen
It may lead to settle down and make available smaller number of nano-particles adjacent to the electrode surface for incorporation.
Amorphous alloys offer better corrosion resistance than equivalent polycrystalline materials because of the freedom from grain or grain boundaries and because of the glassy film, which formed on and passivate their surfaces.
The main causes for deterioration of corrosion resistance of NiP-Al2O3 composite coating when the concentration of nano-particles increased from 4 to 10 g/L are: ① with the increase of Al2O3 particles in the composite coating, interface between metal matrix and particles enlarged, the discontinuous interface surrounded particles have interspace, the agglomerates of particles leaded to uneven surface, and the particles had not been effectively covered by NiP alloy; ②a large amount of added Al2O3 nano-particles wedged in and fragmented the original integrated and uniform coating and passive film, enlarging the interface area of coating, increasing interface energy and increasing the number of corrosion microcell.
Amorphous alloys offer better corrosion resistance than equivalent polycrystalline materials because of the freedom from grain or grain boundaries and because of the glassy film, which formed on and passivate their surfaces.
The main causes for deterioration of corrosion resistance of NiP-Al2O3 composite coating when the concentration of nano-particles increased from 4 to 10 g/L are: ① with the increase of Al2O3 particles in the composite coating, interface between metal matrix and particles enlarged, the discontinuous interface surrounded particles have interspace, the agglomerates of particles leaded to uneven surface, and the particles had not been effectively covered by NiP alloy; ②a large amount of added Al2O3 nano-particles wedged in and fragmented the original integrated and uniform coating and passive film, enlarging the interface area of coating, increasing interface energy and increasing the number of corrosion microcell.
Online since: January 2019
Authors: Yong Mao, Kai Xiong, Shun Meng Zhang, Ying Jie Sun
(9)
In these formulas, h indexes Planck’s constants, k is Boltzmann’s constants, NA indexes Avogadro’s number, ρ is the density, M stands for the mass of unit cell, n is the number of atoms in the unit cell, νm is the averaged elastic wave velocity, νl and νt point to the longitudinal sound velocity and transverse sound velocity.
[4] FuZhi Dai, Yanchun Zhou, Wei Sun, Segregation of solute atoms (Y, Nb, Ta, Mo and W) in ZrB2 grain boundaries and their effects on grain boundary strengths: A first-principles investigation.
[4] FuZhi Dai, Yanchun Zhou, Wei Sun, Segregation of solute atoms (Y, Nb, Ta, Mo and W) in ZrB2 grain boundaries and their effects on grain boundary strengths: A first-principles investigation.
Online since: May 2012
Authors: Xian Xiong Cheng, Yong Hong Zhao, Tao Zhang, Dan Zhou
The distance between charge point and surface was shortened by the nanoscale particles,so the electronic number that was transferred by the charge.The catalyst that was researched by the ultraviolet radiation response was more,but ultraviolet radiation was small in the sunlight.
Transition metal ions and tombarthite elements were doped in the surface of TiO2 Catalyst,which could make TiO2 lattice engender defect,Change crystallinity and alter the particles structure and surface properties, accordingly, the light response range was extended,and the effective separation light electronic-the cavity was promoted,lastly, the catalyst photocatalytic activity was improved[3-7].The results of Srinivasan[8] shew that Sol–gel synthesis and sulfation process has been carried out to prepare Fe3+/Zn2+ co-doped and SO42− impregnated TiO2 photocatalysts, Structural (XRD) characteristics of SO42− impregnated TiO2 reveals the presence of anatase nanoparticles with average grain sizes of 9.8 and 14.8 nm.
From the coordination number of 4.3 and a Pt−Cl distance of 2.28 Å, as calculated from extended X-ray absorption fine structure results, we conclude that the platinum salt is present as PtCl4.
Compound Semiconductor was the effective means to improve the efficiency of the photocatalytic.It is essence that a kind of grain was decorated by another kind of particle actually.The separation efficiency of the system charge can be improved through the semiconductor compound, such as TiO2-CdS,TiO2-SnO2,TiO2-WO3,TiO2-SiO2,V2O5-TiO2, and TiO2 spectral response range was expanded, which was helpful for the sun effective acquisition[29-31].The results of Zhang Changyuan[32] shew that the TiO2/γ-MnO2 composite materials were prepared by one-step hydrothermal process using TiCl3 and KMnO4.The UV-Vis absorption spectra of composite materials illuminated a wide absorbency ranging from UV light to visible light; and band-gap was estimated to 3.03 eV.
Transition metal ions and tombarthite elements were doped in the surface of TiO2 Catalyst,which could make TiO2 lattice engender defect,Change crystallinity and alter the particles structure and surface properties, accordingly, the light response range was extended,and the effective separation light electronic-the cavity was promoted,lastly, the catalyst photocatalytic activity was improved[3-7].The results of Srinivasan[8] shew that Sol–gel synthesis and sulfation process has been carried out to prepare Fe3+/Zn2+ co-doped and SO42− impregnated TiO2 photocatalysts, Structural (XRD) characteristics of SO42− impregnated TiO2 reveals the presence of anatase nanoparticles with average grain sizes of 9.8 and 14.8 nm.
From the coordination number of 4.3 and a Pt−Cl distance of 2.28 Å, as calculated from extended X-ray absorption fine structure results, we conclude that the platinum salt is present as PtCl4.
Compound Semiconductor was the effective means to improve the efficiency of the photocatalytic.It is essence that a kind of grain was decorated by another kind of particle actually.The separation efficiency of the system charge can be improved through the semiconductor compound, such as TiO2-CdS,TiO2-SnO2,TiO2-WO3,TiO2-SiO2,V2O5-TiO2, and TiO2 spectral response range was expanded, which was helpful for the sun effective acquisition[29-31].The results of Zhang Changyuan[32] shew that the TiO2/γ-MnO2 composite materials were prepared by one-step hydrothermal process using TiCl3 and KMnO4.The UV-Vis absorption spectra of composite materials illuminated a wide absorbency ranging from UV light to visible light; and band-gap was estimated to 3.03 eV.
Online since: October 2010
Authors: L. Perazolli, G.F. Pegler, M.R.A. Silva, R.A.F. Ingino, J.A. Varela
A growing number of research works has been concentrating its efforts on understanding the decomposition mechanisms of phenol and its derivatives.
Particles in suspension forming colloidal solutions are largely of special interest once they unfold an enormous specific area, which provides conditions that increase the number of reaction sites for photodegradation [3].
The increase in photoactivity is attributed to the Ag° deposited on the particles surface associated to the formation of grain contour, which contain the said Ag° during the thermal treatment.
The silver observed in the grain contours tends to increase the conductivity between the particles TiO2 and SnO2, and acts as electron accumulator [15], while the Ag° acts on the particles surface according to the equations 1 and 2.
Particles in suspension forming colloidal solutions are largely of special interest once they unfold an enormous specific area, which provides conditions that increase the number of reaction sites for photodegradation [3].
The increase in photoactivity is attributed to the Ag° deposited on the particles surface associated to the formation of grain contour, which contain the said Ag° during the thermal treatment.
The silver observed in the grain contours tends to increase the conductivity between the particles TiO2 and SnO2, and acts as electron accumulator [15], while the Ag° acts on the particles surface according to the equations 1 and 2.
Online since: October 2006
Authors: Miguel Algueró, L. Pardo, K. Brebøl
The polarization in the randomly oriented grains of an as-processed ferroelectric ceramic
can be oriented in the direction of an external electric field, in the so-called "poling" process
(Fig.1), giving as a result an induced anisotropy of the properties and a piezoelectric effect [1].
Left: Schematic view of grains of a ferroelectric ceramic showing the polarization direction before (up) and after (down) the poling process.
In the first publications on the method, the complex characterization of a number of commercial piezoceramics (Ferroperm Piezoceramics A/S), with high (PZ27, lead circonate titanate) and low (PZ34, modified lead titanate, and PZ45, bismuth niobate) coupling coefficients and with high (PZ27) and low (PZ35, lead metaniobate) mechanical quality factors, was accomplished.
Although still fully valid, some of the calculation details given in the first works have benefited from the long experience of application of the method to a wide number of ceramic materials [24-27] and has been refined to be easier to use in the research and industrial characterization and quality control laboratories.
Left: Schematic view of grains of a ferroelectric ceramic showing the polarization direction before (up) and after (down) the poling process.
In the first publications on the method, the complex characterization of a number of commercial piezoceramics (Ferroperm Piezoceramics A/S), with high (PZ27, lead circonate titanate) and low (PZ34, modified lead titanate, and PZ45, bismuth niobate) coupling coefficients and with high (PZ27) and low (PZ35, lead metaniobate) mechanical quality factors, was accomplished.
Although still fully valid, some of the calculation details given in the first works have benefited from the long experience of application of the method to a wide number of ceramic materials [24-27] and has been refined to be easier to use in the research and industrial characterization and quality control laboratories.