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Online since: January 2012
Authors: Zhen Lei Guo, Yan Kun Zhang, Er Yan Chen
            
                Haydite 
Grain size(mm)
1h bibulous water
Cylinder pressure strength(MPa)
Coefficient of softness
packing density  (kg/m3)
5--20
8%
6.0
80%
740 
Table 2.
Concrete Design ( kg/m³) Number Light-weight Aggregate Water-cement ratio Cement Water Sands Shale Gravel A 0% 0.35 450 133 875 0 1125 B 25% 0.5 450 215 875 150 844 C 50% 0.3 450 130 875 300 563 D 62.5% 0.45 450 202 875 375 422 E 75% 0.25 450 122 875 450 281 F 100% 0.4 450 204 875 600 0 Test Results and analysis Test Results.
Table 3 Compressive strength Number Cube compressive strength fcu/MPa Prism compressive strength fc(MPa) (28thday) 7th day 14thday 28thday 1 53.4 56.4 61.5 54.2 2 35.6 42.4 47.5 41.9 3 48.8 53.8 56.5 49.7 4 37.0 42.0 45.5 40.9 5 45.1 50.4 52.5 46.5 6 33.4 40.8 44.5 38.2 The regression equation suggests , x1 is lightweight aggregate volume fraction and x2 is water-cement ratio.
Table 5 Test Value and Calculated value of Cube Compressive Strength(MPa) Number Test Value Calculated value (Calculated value-Test value)/ Test Value (%) 1 61.5 60.4 -1.79 2 47.5 48.8 2.74 3 56.5 55.6 -1.59 4 45.5 45.9 0.879 5 52.5 54.5 3.81 6 44.5 42.9 -3.6 Table 6 Cube Compressive Strength (on 28th day, for example) Water-cement ratio Light-weight Aggregate 0.25 0.3 0.35 0.4 0.45 0.5 0% 65.6 63 60.4 57.7 55.1 52.5 25% 61.9 59.3 56.7 54.0 51.4 48.8 50% 58.2 55.6 53.0 50.3 47.7 45.1 62.5% 56.3 53.7 51.1 48.5 45.9 43.2 75% 54.5 51.9 49.2 46.6 44.0 41.4 100% 50.8 48.2 45.5 42.9 40.3 37.7 Table 7 Compressive Strength (water-cement ratio0.35, for example)(MPa) Light-weight Aggregate 0% 25% 50% 62.5% 75% 100% fcu 7th day 52.3 48.3 44.3 42.3 40.3 36.3 14th day 55.8 52.6 49.4 47.8 46.2 43.0 28th day 60.4 56.7 53.0 51.1 49.2 45.5 53.5 50.1 46.7 45.0 43.3 39.9 0.886 0.884 0.881 0.881 0.880 0.877 Age coefficient of concrete is the ratio of the compressive strength on any age and compressive
            
    Concrete Design ( kg/m³) Number Light-weight Aggregate Water-cement ratio Cement Water Sands Shale Gravel A 0% 0.35 450 133 875 0 1125 B 25% 0.5 450 215 875 150 844 C 50% 0.3 450 130 875 300 563 D 62.5% 0.45 450 202 875 375 422 E 75% 0.25 450 122 875 450 281 F 100% 0.4 450 204 875 600 0 Test Results and analysis Test Results.
Table 3 Compressive strength Number Cube compressive strength fcu/MPa Prism compressive strength fc(MPa) (28thday) 7th day 14thday 28thday 1 53.4 56.4 61.5 54.2 2 35.6 42.4 47.5 41.9 3 48.8 53.8 56.5 49.7 4 37.0 42.0 45.5 40.9 5 45.1 50.4 52.5 46.5 6 33.4 40.8 44.5 38.2 The regression equation suggests , x1 is lightweight aggregate volume fraction and x2 is water-cement ratio.
Table 5 Test Value and Calculated value of Cube Compressive Strength(MPa) Number Test Value Calculated value (Calculated value-Test value)/ Test Value (%) 1 61.5 60.4 -1.79 2 47.5 48.8 2.74 3 56.5 55.6 -1.59 4 45.5 45.9 0.879 5 52.5 54.5 3.81 6 44.5 42.9 -3.6 Table 6 Cube Compressive Strength (on 28th day, for example) Water-cement ratio Light-weight Aggregate 0.25 0.3 0.35 0.4 0.45 0.5 0% 65.6 63 60.4 57.7 55.1 52.5 25% 61.9 59.3 56.7 54.0 51.4 48.8 50% 58.2 55.6 53.0 50.3 47.7 45.1 62.5% 56.3 53.7 51.1 48.5 45.9 43.2 75% 54.5 51.9 49.2 46.6 44.0 41.4 100% 50.8 48.2 45.5 42.9 40.3 37.7 Table 7 Compressive Strength (water-cement ratio0.35, for example)(MPa) Light-weight Aggregate 0% 25% 50% 62.5% 75% 100% fcu 7th day 52.3 48.3 44.3 42.3 40.3 36.3 14th day 55.8 52.6 49.4 47.8 46.2 43.0 28th day 60.4 56.7 53.0 51.1 49.2 45.5 53.5 50.1 46.7 45.0 43.3 39.9 0.886 0.884 0.881 0.881 0.880 0.877 Age coefficient of concrete is the ratio of the compressive strength on any age and compressive
Online since: October 2010
Authors: Guerold Sergueevitch Bobrovinitchii, Sérgio Neves Monteiro, Ana Lúcia Diegues Skury
            
                This type of processing permitted to obtain a more uniform structure for the composites with ultrafine layers of the binding compounds separating dispersed cBN grains.
The cycling pressure was performed by alternating two different levels: 7.7 GPa at 1800°C for 3 minutes and 4.5 GPa at 30°C for a certain number of cycles.
In this figure one should note evidences of intergranular fracture, which occurred separating crystalline grains that form the cBN particles.
            
    The cycling pressure was performed by alternating two different levels: 7.7 GPa at 1800°C for 3 minutes and 4.5 GPa at 30°C for a certain number of cycles.
In this figure one should note evidences of intergranular fracture, which occurred separating crystalline grains that form the cBN particles.
Online since: July 2011
Authors: Rui Luo, Ping Chen, Ting Yang, Hui Zong Zhang, Ping Li, Ya Wu Zeng
            
                “Loose points inside” means getting a small number of inner points which were far from the surface.
(1)Study the influence of α on the number of sphere and the smoothness of the DEM model.
(2)Analyze the influence of β on the number of spheres and the overlapping degree of the model.
Then, two parameters were introduced to reduce the number of sphere while meeting the accuracy in profile.
Discrete element modeling for irregularly-shaped sand grains.
            
    (1)Study the influence of α on the number of sphere and the smoothness of the DEM model.
(2)Analyze the influence of β on the number of spheres and the overlapping degree of the model.
Then, two parameters were introduced to reduce the number of sphere while meeting the accuracy in profile.
Discrete element modeling for irregularly-shaped sand grains.
Online since: April 2016
Authors: Roland Pawliczek, Krzysztof Kluger
            
                Dang Van’s fatigue model
The Dang Van fatigue criterion [6] is distinguished by mesoscopic (grain boundary) stress observation scale.
Pawliczek-Gasiak model It was indicated that material sensitivity on mean loading depends on the actual loading level defining different value of the destructive cycle’s number [9].
The effect of loading conditions and material sensitivity change on mean loading value, together with the number of destructive cycles for SJ355 steel are presented in [10, 13].
When determining the ψ factor, the change in its value is considered regarding the number N of cycles [10].
There were also presented models taking into account the different sensitivity of the material to mean loads, depending on the number of destructive cycles.
            
    Pawliczek-Gasiak model It was indicated that material sensitivity on mean loading depends on the actual loading level defining different value of the destructive cycle’s number [9].
The effect of loading conditions and material sensitivity change on mean loading value, together with the number of destructive cycles for SJ355 steel are presented in [10, 13].
When determining the ψ factor, the change in its value is considered regarding the number N of cycles [10].
There were also presented models taking into account the different sensitivity of the material to mean loads, depending on the number of destructive cycles.
Online since: November 2011
Authors: Yan Lin Chen, Ming Yan, Yi Ming Sun, Jiao Qun Zhu
            
                Europium-doped nanocrystalline ZrO2: Eu3+ powders with different doped concentrations were prepared by emulsion processing method, with different doped concentration and calcination temperature on the material grain size, structure, size and luminescent properties.
With a large number of mechanical and other properties of ZrO2 research compared the less research of optical properties relatively, ZrO2 has low phonon energy (470cm) because the low phonon energy can reduce the multi-phonon nonradiative relaxation probability, so the ZrO2 matrix for luminescent materials can be used as an ideal material.
Rare earth ions has the unique configuration of 4fN transitions between energy levels within the formation of multi-level number, the transition between energy levels and more can be formed from the ultraviolet to the infrared light of various spectral bands, and rare earth ions spectrum belongs to the class of narrow-band spectrum of atoms, therefore, pure light color, is ideal for active ion light-emitting materials [10].
Shown in Fig.3, this figure is the emission spectra doped n (Eu3+): n (Zr4+) 2% of ZrO2:Eu3+ samples at 600,800 and 1000℃, and expressed as a, b, c sample number.
            
    With a large number of mechanical and other properties of ZrO2 research compared the less research of optical properties relatively, ZrO2 has low phonon energy (470cm) because the low phonon energy can reduce the multi-phonon nonradiative relaxation probability, so the ZrO2 matrix for luminescent materials can be used as an ideal material.
Rare earth ions has the unique configuration of 4fN transitions between energy levels within the formation of multi-level number, the transition between energy levels and more can be formed from the ultraviolet to the infrared light of various spectral bands, and rare earth ions spectrum belongs to the class of narrow-band spectrum of atoms, therefore, pure light color, is ideal for active ion light-emitting materials [10].
Shown in Fig.3, this figure is the emission spectra doped n (Eu3+): n (Zr4+) 2% of ZrO2:Eu3+ samples at 600,800 and 1000℃, and expressed as a, b, c sample number.
Online since: November 2007
Authors: Yu Fei Gao, Pei Qi Ge, Zhi Jian Hou
            
                It 
shows that in the case of wire-sawing velocity of 10m/s or higher, infeed velocity of 0.20mm/s and 
diamond grain size of 64µm or smaller, the chip formation and material removal is in a brittle 
regime mainly, but the silicon wafer surface formation is sawed in a ductile regime.
The number of grits participating in cutting in dAn is dNc=Ns·dAn (where Ns is the number of dynamic effective abrasives per unit area).
The number of dynamic effective abrasives Ns which isn't a constant value, relating with distribution density, height of grits, wire speed, feed speed and the elastic deformation of wire, is very complicated.
            
    The number of grits participating in cutting in dAn is dNc=Ns·dAn (where Ns is the number of dynamic effective abrasives per unit area).
The number of dynamic effective abrasives Ns which isn't a constant value, relating with distribution density, height of grits, wire speed, feed speed and the elastic deformation of wire, is very complicated.
Online since: October 2010
Authors: Harald Harmuth, Sandra Vollmann
            
                Thereby the fines are dissolved favourably which degenerates the grain/matrix bound and enables erosive wear.
To give an example for a rotating disc assuming laminar flow the following equation holds according to [4]: (5) In Eq. 5 Sh denotes the Sherwood number, Re is the Reynolds number and Sc is the Schmidt number that are defined as follows: (6) (7) (8) Here L is a significant length, u denotes a significant velocity and n is the kinematic fluid viscosity.
From the mass transfer coefficient resultant from the simulation Sherwood number was calculated.
Table 2 shows the dimensionless numbers defined by model settings as well as the dimensionless mass transfer coefficients (Sherwood numbers) for the calculated models.
A similar critical Reynolds number may be deduced for Eq. 11.
            
    To give an example for a rotating disc assuming laminar flow the following equation holds according to [4]: (5) In Eq. 5 Sh denotes the Sherwood number, Re is the Reynolds number and Sc is the Schmidt number that are defined as follows: (6) (7) (8) Here L is a significant length, u denotes a significant velocity and n is the kinematic fluid viscosity.
From the mass transfer coefficient resultant from the simulation Sherwood number was calculated.
Table 2 shows the dimensionless numbers defined by model settings as well as the dimensionless mass transfer coefficients (Sherwood numbers) for the calculated models.
A similar critical Reynolds number may be deduced for Eq. 11.
Online since: December 2012
Authors: Hai De Hu
            
                RII = (CR/CT –R/S)*100                                     (1)
Where CR stands for the area of residential area contained in buffer zones; CT stands for the area of total residential area; R stands for the area of road buffer zones; S stands for the area of whole study region; The number 100 is used for converting to a percentage form.
Fig. 3 Increase rate of built-up area in Coastal Urban Belt in Liaoning In March of 2001 the Chinese government initiated a countrywide project – refer to as the Grain-for-Green Policy (GFGP) – help restore the ecological balance in mountainous areas by returning steep cultivated land to forest and pasture[8].
Characteristics of Steep Cultivated Land and the Impact of the Grain-for-Green Policy in China1.
            
    Fig. 3 Increase rate of built-up area in Coastal Urban Belt in Liaoning In March of 2001 the Chinese government initiated a countrywide project – refer to as the Grain-for-Green Policy (GFGP) – help restore the ecological balance in mountainous areas by returning steep cultivated land to forest and pasture[8].
Characteristics of Steep Cultivated Land and the Impact of the Grain-for-Green Policy in China1.
Online since: October 2012
Authors: Hong Zhu Quan
            
                As a matter of fact, the research of the GC residues just started in the cord about the IGCC system as for the coal gasifier because there were not a lot of numbers about the gas collection plant too much yet.
Mixing with classified particles controlled grain size distribution.
Table 2 Grain size distribution and physical property Under 5.0mm (%) Under 2.5mm (%) Under 1.2mm (%) Under 0.6mm (%) Under 0.3mm (%) Under 0.15mm (%) Density (g/cm3) BET (m2/g) Water absorption (%) Needle content (%) IGCC slag 93 84 39 8 2 1 2.45 0.10 0.6 0.5 Sewage sludge slag 94 65 26 13 4 1 2.52 0.22 1.5 0.6 Municipal waste slag 100 86 54 10 3 1 2.67 0.58 3.5 0.3 Ferro-nickel slag 99 55 22 5 1 0 2.89 0.12 0.8 0 River sand 96 88 59 38 22 8 2.79 1.75 1.4 0 Japaneses desirable sand 99-100 80-100 50-90 25-65 10-35 2-10 ≥2.5 - ≤3.0 - Table 3 : Cement production test's condition Unit of electric crushing power 19.7 kWh/t/clinker Volume of crush in mill 193t clinker/E Content of 0.09mm under particle 18% Output of mixing raw material 7160 t/day Using calorillic power 778 Kcal/kg HM value t=CaO/ SiO2+ Al2O3+ Fe2O3 2.15 Free lime content 0.40% Table 4 : Results from mortar test Water absorption (%) Mortar flow ratio (%) Mortar air content (%) Crack content (%) IGCC slag
            
    Mixing with classified particles controlled grain size distribution.
Table 2 Grain size distribution and physical property Under 5.0mm (%) Under 2.5mm (%) Under 1.2mm (%) Under 0.6mm (%) Under 0.3mm (%) Under 0.15mm (%) Density (g/cm3) BET (m2/g) Water absorption (%) Needle content (%) IGCC slag 93 84 39 8 2 1 2.45 0.10 0.6 0.5 Sewage sludge slag 94 65 26 13 4 1 2.52 0.22 1.5 0.6 Municipal waste slag 100 86 54 10 3 1 2.67 0.58 3.5 0.3 Ferro-nickel slag 99 55 22 5 1 0 2.89 0.12 0.8 0 River sand 96 88 59 38 22 8 2.79 1.75 1.4 0 Japaneses desirable sand 99-100 80-100 50-90 25-65 10-35 2-10 ≥2.5 - ≤3.0 - Table 3 : Cement production test's condition Unit of electric crushing power 19.7 kWh/t/clinker Volume of crush in mill 193t clinker/E Content of 0.09mm under particle 18% Output of mixing raw material 7160 t/day Using calorillic power 778 Kcal/kg HM value t=CaO/ SiO2+ Al2O3+ Fe2O3 2.15 Free lime content 0.40% Table 4 : Results from mortar test Water absorption (%) Mortar flow ratio (%) Mortar air content (%) Crack content (%) IGCC slag
        The Study of Epoxidation of Allyl Chloride Catalyzed by Silica-Based HTMS-3A in Chemical Engineering
    
    Online since: October 2012
Authors: Xue Peng Liu, Dong Mei Zhao
            
                Introduction
This subject is to be squeezed in the article the method of forming the preparation of a type load TS 1 catalyst of epoxy allyl chloride laboratory research, solve the molecular sieve grain size small, recycling, the difficult question, improve epichlorohydrin and chlorine propanediol yield, lower high boiling point by-products, using the technology for production of epichlorohydrin industrialization in chemical engineering.
NaOH content on the catalyst effect on the strength of broken When NaOH addition amount is low, because the dosage of the water must be, alkali concentration is not high, and there is a large part of the oxidation silicon and TS filling a 1 through the, the particles of the outer surface of the doesn't work, can not reach the glue dissolve effect; When NaOH addition amount of increase, the higher concentration, except with NaOH powder in the hole outside, still have enough NaOH exist in between particles and grain, make each other particles dissolve connection become fully glue; But, when NaOH quantity increased again, the surplus, not dissolve in glue, the ultimate strength of catalyst have no effect.
When the response time is 4 h, in TS a 1/510: the chlorine propylene glycol and high boiling the yield that there were a low and make epichlorohydrin selective peak, and for pure TS suck, because of chlorine propylene glycol and high boiling the yield of things has increased dramatically reduce the epichlorohydrin and the selective; When the response time is longer (6 h or sh) : catalytic reaction because of chlorine propylene glycol and the generation of high boiling content increases, epichlorohydrin selectivity declined, but the side effects of small speed up speed, and make the of epichlorohydrin yield increased slightly, as for pure TS one, although chlorine propanediol yield increase is not big, but because a large number of high boiling content generation and make of epichlorohydrin selective significantly reduced.
            
    NaOH content on the catalyst effect on the strength of broken When NaOH addition amount is low, because the dosage of the water must be, alkali concentration is not high, and there is a large part of the oxidation silicon and TS filling a 1 through the, the particles of the outer surface of the doesn't work, can not reach the glue dissolve effect; When NaOH addition amount of increase, the higher concentration, except with NaOH powder in the hole outside, still have enough NaOH exist in between particles and grain, make each other particles dissolve connection become fully glue; But, when NaOH quantity increased again, the surplus, not dissolve in glue, the ultimate strength of catalyst have no effect.
When the response time is 4 h, in TS a 1/510: the chlorine propylene glycol and high boiling the yield that there were a low and make epichlorohydrin selective peak, and for pure TS suck, because of chlorine propylene glycol and high boiling the yield of things has increased dramatically reduce the epichlorohydrin and the selective; When the response time is longer (6 h or sh) : catalytic reaction because of chlorine propylene glycol and the generation of high boiling content increases, epichlorohydrin selectivity declined, but the side effects of small speed up speed, and make the of epichlorohydrin yield increased slightly, as for pure TS one, although chlorine propanediol yield increase is not big, but because a large number of high boiling content generation and make of epichlorohydrin selective significantly reduced.