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Online since: October 2020
Authors: Igor V. Dolbin, Gusein M. Magomedov, Georgii V. Kozlov
Discovery of grapheme and a number of other two-dimensional (2D) nanofillers (for example, boron nitride, grapheme oxide a.a.), prossessing very high characteristics, creates a new class of nanostructured materials polymer/2D-nanofiller [4].
This fraction jds is estimated as follows [17]: , (5) where s is thickness of boundary region, L is size of nanomaterial grain.
As it is known [13], 2D-nanofiller platelets can be either isolated, i.e. their number Npl per one aggregate is equal to one (exfoliated structure), or they can form “packets” (tactoids) and then Npl>1 (intercalated structure of 2D-nanofiller).
In Fig. 5 the dependence of index a on a number of 2D-nanofiller platelets per “packet” (tactoid) Npl is adduced for the considered nanocomposites.
Conclusions Thus, the present work results allow to make a number of non-standard conclusions.
This fraction jds is estimated as follows [17]: , (5) where s is thickness of boundary region, L is size of nanomaterial grain.
As it is known [13], 2D-nanofiller platelets can be either isolated, i.e. their number Npl per one aggregate is equal to one (exfoliated structure), or they can form “packets” (tactoids) and then Npl>1 (intercalated structure of 2D-nanofiller).
In Fig. 5 the dependence of index a on a number of 2D-nanofiller platelets per “packet” (tactoid) Npl is adduced for the considered nanocomposites.
Conclusions Thus, the present work results allow to make a number of non-standard conclusions.
Online since: May 2019
Authors: Du Yeol Kim, Soon Ki Jeong, Ha Jin Lee
The general grain size and crystal surface of the synthesized CuHCF active materials were confirmed from the scanning electron microscopy (SEM) images.
As shown in Figs. 1(a)–(d), the XRD profiles can be well indexed to standard CuHCF (JCPDS card number 86-0513) [20].
Jeong, Modulating the hydration number of calcium ions by varying the electrolyte concentration: Electrochemical performance in a Prussian blue electrode/aqueous electrolyte system for calcium-ion batteries, Electrochimica Acta. 265 (2018) 430−436 [19] R.
As shown in Figs. 1(a)–(d), the XRD profiles can be well indexed to standard CuHCF (JCPDS card number 86-0513) [20].
Jeong, Modulating the hydration number of calcium ions by varying the electrolyte concentration: Electrochemical performance in a Prussian blue electrode/aqueous electrolyte system for calcium-ion batteries, Electrochimica Acta. 265 (2018) 430−436 [19] R.
Online since: December 2011
Authors: Cheng Bin Li, Wei Du, Guo Sen Yuan
In this extrusion forming temperature range, the blank would show the less deformation resistance, better plastic, easier forming and better distortion than cold extrusion, so as to reduce the number of working procedure.
If cannot effectively isolate the die and the workpiece, the friction will produce abrasive grain and adhesion abrasion, then result in scrapes and adhesion on the mold surface,will finally give rise to cracks on the mold surface, have a rough surface of the extrusion, and the dimensions exceed size tolerance, reduced the service life of mold,thus, in order to diminish the friction, brushing lubricant on the mold or the blank is needed in the process of extrusion.
Using the warm extrusion to process the forging die cavity of 3Cr2W8V in One-off Forming Technology,Realized chipless forming, reduced manufacturing processes of the forging die, Streamlined a large number of special tools and fixture during the original process,largely reduced the cycle of mold manufacturing,improved the manufacturing efficiency,saved the Integrated material consumption more than 30%, dramatically reduced the manufacturing cost;The size precision of forging die cavity will up to grade 3,the surface roughness less than Ra1.6μm,the mechanical property better than the original technology,increased the service life of forging die 3~5 times;and easy in replacement, convenient in operation, safe and reliable.
If cannot effectively isolate the die and the workpiece, the friction will produce abrasive grain and adhesion abrasion, then result in scrapes and adhesion on the mold surface,will finally give rise to cracks on the mold surface, have a rough surface of the extrusion, and the dimensions exceed size tolerance, reduced the service life of mold,thus, in order to diminish the friction, brushing lubricant on the mold or the blank is needed in the process of extrusion.
Using the warm extrusion to process the forging die cavity of 3Cr2W8V in One-off Forming Technology,Realized chipless forming, reduced manufacturing processes of the forging die, Streamlined a large number of special tools and fixture during the original process,largely reduced the cycle of mold manufacturing,improved the manufacturing efficiency,saved the Integrated material consumption more than 30%, dramatically reduced the manufacturing cost;The size precision of forging die cavity will up to grade 3,the surface roughness less than Ra1.6μm,the mechanical property better than the original technology,increased the service life of forging die 3~5 times;and easy in replacement, convenient in operation, safe and reliable.
Online since: June 2011
Authors: Hsin Yi Lee, Hung Wei Yen, Jer Ren Yang, Hsiao Tzu Chang
As can be seen in this figure, the microstructure contains austenite and small amounts of undissolved M7C3 carbide embedded in the grain boundaries.
Therefore, a large number of twinned boundaries can promote precipitations.
Additionally, the midrib region of the martensite, containing a large number of twinned boundaries, is the preferential position for carbide precipitations.
Therefore, a large number of twinned boundaries can promote precipitations.
Additionally, the midrib region of the martensite, containing a large number of twinned boundaries, is the preferential position for carbide precipitations.
Online since: July 2011
Authors: Keisuke Tanaka, Yasuki Kita
The grain size of SiC particles was 100 to 250 mm.
Fatigue tests were interrupted at prescribed numbers of cycles.
Figure 3 shows SEM micrographs taken from the notch root of the fatigued specimen under the maximum nominal stress 6.0 MPa at the frequency 30 Hz to the number of the stress cycles N=10272.
Fatigue tests were interrupted at prescribed numbers of cycles.
Figure 3 shows SEM micrographs taken from the notch root of the fatigued specimen under the maximum nominal stress 6.0 MPa at the frequency 30 Hz to the number of the stress cycles N=10272.
Online since: July 2011
Authors: Ying Xu, Yan Qing Cai, Xiang Lu, Peng Hua Ma
Introduction
Vanadium is a rare transition metal, which can refine crystal grain and improve the toughness, hardness and mechanical strength of steel, and 85% to 90% of the vanadium is mixed in steel as the alloy braced for steel-making.
With the substantial growth of Chinese steel production, a large number of slag containing vanadium is let out every year in Panzhihua of Sichuan, Maanshan of Anhui and Chengde of Hebei[2].
When pH of reaction liquid maintained at about 8, according to the law of mass action, number of CO32- ions are present, which is apt to the positive reaction.
With the substantial growth of Chinese steel production, a large number of slag containing vanadium is let out every year in Panzhihua of Sichuan, Maanshan of Anhui and Chengde of Hebei[2].
When pH of reaction liquid maintained at about 8, according to the law of mass action, number of CO32- ions are present, which is apt to the positive reaction.
Online since: May 2011
Authors: Jing Yan Li
The Finite Element Analysis of Coupling Law of Stress Field / Seepage Field in Impermeable Stratum Medium
Jingyan Li
Institute of Marine Geosciences,Ocean University of China
Number 238, SongLing Road, LaoShan District, Qingdao City of Shandong, China , 266100
zzjhym@sina.com
Key words: Porous medium; Seepage field; Stress field; Coupling Law; Mathematical model; Numerical simulation; finite element.
Seepage theory and application about fluid flow of deformable saturated reservoir, non-miscible two-phase seepage saturated, seepage of fractured rock, fractured gas reservoirof low permeability, reservoir after fracturing, ground water, natural gas and coal reservoirs, low permeability reservoir, flow-solid-heat three coupled etc have been studied and examples simulated respectively by domestic scholars ,at the same time a number of interesting conclusions and understanding have been got.
Mathematical model of rock stratum skeleton 2.1 Equation of continuity (1) In it: - Media density of dry porous;-Velocity of the solid skeleton; Let the density of solid particles-;so, (2) To the clastic reservoir rocks such as sandstone,because its main component are hard and compact quartz, feldspar grains, rock particle density can be set the same , that ρs = constant,so (3) Using the the relationship between material derivative and spatial derivatives,then (3) becomes (4) According to In the small deformation theory of solid mechanics, it assumes that material derivative is approximately
Seepage theory and application about fluid flow of deformable saturated reservoir, non-miscible two-phase seepage saturated, seepage of fractured rock, fractured gas reservoirof low permeability, reservoir after fracturing, ground water, natural gas and coal reservoirs, low permeability reservoir, flow-solid-heat three coupled etc have been studied and examples simulated respectively by domestic scholars ,at the same time a number of interesting conclusions and understanding have been got.
Mathematical model of rock stratum skeleton 2.1 Equation of continuity (1) In it: - Media density of dry porous;-Velocity of the solid skeleton; Let the density of solid particles-;so, (2) To the clastic reservoir rocks such as sandstone,because its main component are hard and compact quartz, feldspar grains, rock particle density can be set the same , that ρs = constant,so (3) Using the the relationship between material derivative and spatial derivatives,then (3) becomes (4) According to In the small deformation theory of solid mechanics, it assumes that material derivative is approximately
Online since: November 2012
Authors: Jian Xin Kuang, Xin Heng Wang, An Min Liu
This is due to the carbon content of Ni25 alloy is low and chromium-free, so the melting point second phase particles is less during solidification, the effect to prevent grain growth is also weak.
Therefore its cladding microstructure is coarse and dendrite is clear.Melting point of Ni60 alloy is low, the coagulation time is longer, the chromium content is less than Ni21,the number of high melting point compounds is relatively less during solidification,so its cladding microstructure is more thicker than that of Ni21 +20% WC +0.5% CeO2.
Figure 2 is a contrast histogram of high-temperature dry friction and wear ofcladding layer with different composition under the same experimental conditions.As can be seen from the figure, the wear of Ni21 +20% WC +0.5% CeO2 cladding layer is minimal, Its wear resistance is best,and wear resistance of Ni60 +20% WC +0.5% CeO2 cladding layer is worst.This is closely related to the level of cladding layer hardness, uniform and dense of the microstructure, High and low of the melting point.The microstructure of Ni60 +20% WC +0.5% CeO2 cladding layer is dense and small, the number of hard particles of precipitates is more,The hardness of the hard particles is high and fall flat with the temperature drop,so its high-temperature wear resistance is the best. 1.Ni60 +20% WC +0.5% CeO2 2.
Therefore its cladding microstructure is coarse and dendrite is clear.Melting point of Ni60 alloy is low, the coagulation time is longer, the chromium content is less than Ni21,the number of high melting point compounds is relatively less during solidification,so its cladding microstructure is more thicker than that of Ni21 +20% WC +0.5% CeO2.
Figure 2 is a contrast histogram of high-temperature dry friction and wear ofcladding layer with different composition under the same experimental conditions.As can be seen from the figure, the wear of Ni21 +20% WC +0.5% CeO2 cladding layer is minimal, Its wear resistance is best,and wear resistance of Ni60 +20% WC +0.5% CeO2 cladding layer is worst.This is closely related to the level of cladding layer hardness, uniform and dense of the microstructure, High and low of the melting point.The microstructure of Ni60 +20% WC +0.5% CeO2 cladding layer is dense and small, the number of hard particles of precipitates is more,The hardness of the hard particles is high and fall flat with the temperature drop,so its high-temperature wear resistance is the best. 1.Ni60 +20% WC +0.5% CeO2 2.
Online since: March 2015
Authors: Tian Chai, Xing Gu Zhang, De Qi Xiong, Xaio Bing He
The advantage of SOA
SOA is loosely coupled, coarse-grained services architecture, by defining a neutral interface for communication between services, has the following advantages:
(1)Reduce complexity
SOA architecture through loosely and coupled relationship between service requester and provider, shielding the complex business logic of the system.
In order to reduce the amount of read data of AIS next time, the data acquired last time will not be read, it can add a parameter maxim, as well as biggest records number ID had read currently, in AIS database, next time they just take data greater than the current maxim.
Returns the object AIS information services in addition to the largest number of maxid and AIS object group record the current AIS database, including AIS data object each return need ship MMSI longitude, latitude, azimuth angle, lonth breadth, time of occurrence attribute, return structure of AIS information services in Web based on Service XML SOAP forms can be designed as in figure 5.
In order to reduce the amount of read data of AIS next time, the data acquired last time will not be read, it can add a parameter maxim, as well as biggest records number ID had read currently, in AIS database, next time they just take data greater than the current maxim.
Returns the object AIS information services in addition to the largest number of maxid and AIS object group record the current AIS database, including AIS data object each return need ship MMSI longitude, latitude, azimuth angle, lonth breadth, time of occurrence attribute, return structure of AIS information services in Web based on Service XML SOAP forms can be designed as in figure 5.
Online since: June 2014
Authors: Nasri A. Hamid, M.F. Suparin, T. Gokila, L.S. Ewe
The wires have shown higher grain-connectivity, better mechanical properties, and good anti-ballooning property against liquid coolant such as pressurized liquid nitrogen [7].
Component Specification Rated power 1-kW Rotor diameter 1.5 m Blade length 1.5 m Number of blade 3 Swept area 2.25 m2 Tower 3 m, free-stand Cut-in speed 3 m/s Rated speed 7 m/s DI-BSCCO superconducting coils Type H, double pancake of 100 turns Table 1 shows the components and specifications of various components and parameters based on the proposed design.
Acknowledgement This project is supported by the Ministry of Science, Technology and Innovation, Malaysia under Science Fund grant number 03-02-03-SF0232.
Component Specification Rated power 1-kW Rotor diameter 1.5 m Blade length 1.5 m Number of blade 3 Swept area 2.25 m2 Tower 3 m, free-stand Cut-in speed 3 m/s Rated speed 7 m/s DI-BSCCO superconducting coils Type H, double pancake of 100 turns Table 1 shows the components and specifications of various components and parameters based on the proposed design.
Acknowledgement This project is supported by the Ministry of Science, Technology and Innovation, Malaysia under Science Fund grant number 03-02-03-SF0232.