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Online since: July 2020
Authors: Francesco La Via, Peter J. Wellmann, Marcin Zielinski, Marco Mauceri, Michael Schöler, Philipp Schuh, Johannes Steiner, Manuel Kollmuss
Additionally, the samples were polished with a diamond solution with ¼ µm grain size to reduce contamination on the growth front introduced by the merging process.
In order to grow thick 3C-SiC material and to study the impact of the necessary supersaturation that keeps the cubic polytype stable, we have carried out a number of growth experiments and simulations in which the source-to-seed distance was varied between 0.75 mm, 2 mm and 3 mm, respectively.
Acknowledgments This work is funded by the European H2020 framework program for research and innovation under grant agreement number 720827 (CHALLENGE).
In order to grow thick 3C-SiC material and to study the impact of the necessary supersaturation that keeps the cubic polytype stable, we have carried out a number of growth experiments and simulations in which the source-to-seed distance was varied between 0.75 mm, 2 mm and 3 mm, respectively.
Acknowledgments This work is funded by the European H2020 framework program for research and innovation under grant agreement number 720827 (CHALLENGE).
Online since: January 2021
Authors: Jin Chang Ning
In the continuous distribution area of mobile sand dunes in the hinterland of Taklimakan Desert, pure Aeolian sand is adopted at the upper part of the mobile sand dunes with a height of about 15m in the composite longitudinal sand ridges, with the number a (geographic coordinates of the sampling point: N39º17'26.2 ",E83º46'29.4").
On the edge of the desert where mobile dunes are scattered or partially distributed in patches, in the now dried-up ancient river course and in the woodland where Populus euphratica is sparsely growing, silty extremely fine sand due to river siltation (called silty soil in some literatures) is adopted and separated by sieving. only the part less than <0.075mm is used in the test, and the number is z (geographic coordinates of sampling point: N40º49'06.1",E84º17'48.2").
It can be seen that: 1) The relative positions and changing trends of the Surface vibration compaction curve and the Heavy compaction curve are quite consistent, mainly shown in: ①When the content of the Powder clay is less, such as 16.3%, 20%, 25%, 30%, 35%, the gradation of the sample is improved with the increase of the content of the Powder clay, and the increased powder clay is mainly filled in the pores between the sand grains, so that the compaction density is obviously improved on the whole ...
On the edge of the desert where mobile dunes are scattered or partially distributed in patches, in the now dried-up ancient river course and in the woodland where Populus euphratica is sparsely growing, silty extremely fine sand due to river siltation (called silty soil in some literatures) is adopted and separated by sieving. only the part less than <0.075mm is used in the test, and the number is z (geographic coordinates of sampling point: N40º49'06.1",E84º17'48.2").
It can be seen that: 1) The relative positions and changing trends of the Surface vibration compaction curve and the Heavy compaction curve are quite consistent, mainly shown in: ①When the content of the Powder clay is less, such as 16.3%, 20%, 25%, 30%, 35%, the gradation of the sample is improved with the increase of the content of the Powder clay, and the increased powder clay is mainly filled in the pores between the sand grains, so that the compaction density is obviously improved on the whole ...
Online since: July 2020
Authors: Damian Janicki
Scheil solidification paths for Fe-3.6 wt% C-2.5 wt% Si-Ti alloy system with different Ti contents (wt%): (a) 11; (b) 12; (c) 13; (d) 14; (e) 15; (f) 16
The effect of Ti concentration in the molten pool on the number of precipitated phases in the ternary Fe-3.6 wt% C-Ti alloy system under metastable equilibrium condition is shown in figure 3b.
This change in the morphology of the γp dendrites is mainly attributed to a significantly higher thermal stability of the TiC phase than that of the austenite phase, which provides a heterogeneous nucleation of the primary austenite grains.
In such a case, the TiC is the first phase which precipitates from the liquid in the molten pool, and the resultant TiC particles act as nucleating agents for primary austenite grains formation.
Thus, the variation in the fraction of retained austenite with increasing traverse speed at constant HI level and titanium concentration in the molten pool, can be attributed to a change in carbon content in the primary austenite grains, caused by different cooling rates.
Because of its high thermal stability, the TiC phase promotes a heterogeneous nucleation of primary austenite grains, what reduces a cracking tendency of the TRLs.
This change in the morphology of the γp dendrites is mainly attributed to a significantly higher thermal stability of the TiC phase than that of the austenite phase, which provides a heterogeneous nucleation of the primary austenite grains.
In such a case, the TiC is the first phase which precipitates from the liquid in the molten pool, and the resultant TiC particles act as nucleating agents for primary austenite grains formation.
Thus, the variation in the fraction of retained austenite with increasing traverse speed at constant HI level and titanium concentration in the molten pool, can be attributed to a change in carbon content in the primary austenite grains, caused by different cooling rates.
Because of its high thermal stability, the TiC phase promotes a heterogeneous nucleation of primary austenite grains, what reduces a cracking tendency of the TRLs.
Online since: February 2026
Authors: Taiwo Stephen Mogaji, A.M. Akinwole, M.C. Elaine, D.A. Jesugoroye, D.C. James, A.A. Amuleya
To evaluate the energy characteristics of the processed biomass (grain size reduction), proximate and ultimate analyses were conducted on each particle size fraction, assessing parameters such as moisture content, volatile matter, ash content, fixed carbon, elemental composition (carbon, hydrogen, oxygen, nitrogen, and sulfur), and calorific value.
principles of engineering. 2.1.1 Determination of the main shaft speed, 𝑵𝟐 The speed of the main shaft, as described by [12] is calculated using Eq. 1 𝑁1 𝐷1 = 𝑁2 𝐷2 (1) Where: 𝑁1 is the revolution of the smaller pulley (rpm), 𝑁2 is the revolution of the larger pulley or main shaft (rpm), 𝐷1 is the diameter of the driver pulley (mm), 𝐷2 is the diameter of the driven pulley (mm) 2.1.2 Determination of the velocity of the belt According to [12], the velocity of a belt when there is zero slip is determined using Eq. 2 𝑉 = 𝜋𝐷1𝑁1 = 𝜋𝐷2𝑁2 60 60 (2) 2.1.3 Torque transmitted to the main shaft The torque transmitted by the belt to the main shaft, according to [12], is obtained using Eq. 3 T=60p2πN (3) Where: T is the Twisting moment or Torque transmitted in (Nm), P is the Power transmitted to the hammer shaft (hp) 2.1.4 Power transmitted by each belt The relationship between the power transmitted by each belt and the appropriate number
of belts to be used according to [12] is given as in Eq. 4 as follows: n=Total power transmittedPower transmitted by each belt (4) Where: n represents the number of V- belts used 2.1.5 Determination of the Coefficient of increase of belt length and angle of contact of belts.
According to [12], the coefficient of increase of the belt length per unit force was determined using Eq. 5 𝑐 sin ∝ = 𝑅−𝑟 (5) Where: α is the coefficient of increase of the belt length per unit force in degrees (°), R is the radius of the shaft pulley (mm), r is the radius of the motor pulley (mm), C is the Centre distance between the two pulleys (mm) 2.1.6 Determination of the Belt Tension Power transmitted by each belt drive is obtained using Eq. 6 as given by [12] Khurmi and Gupta (2005): 𝑃 = 𝑇1 − 𝑇2 𝑉 × 𝑛 (6) Where: P is the power transmitted by each belt (w), 𝑇1 is the tension in the slack side (N), 𝑇2 is the tension in the tight side of the belt(N), V is the velocity of the belt drive (m/s), n is the number of belts used 2.1.7 Determination of the length of the V belt The length of the belt is obtained using Eq. 7 L=πr2+r1+2x+r2-r12x (7) Where: L is the Length of the belt (mm), x is the centre
end of the belt (mm), 𝑟2 is the radius of the pulleys on the driven end of the belt (mm) 2.1.8 Determination of the weight of the pulley mounted on the shaft The weight of the pulley is determined by using Eq. 8 𝑊𝑝 = 𝑉𝑝𝜌𝑝𝑔 (8) Where: 𝑉𝑝 is the volume of the pulley (m3), 𝜌𝑝 is the density of the pulley material (kg/m3), g is the acceleration due to gravity of the pulley (m/s2) 2.1.9 Determination of the mass of each hammer The mass of each hammer is determined by using Eq. 9, as described by [12]: 𝑀ℎ = 𝜌ℎ × 𝑉ℎ (9) Where: 𝑀ℎ is the mass of the hammer (kg), 𝜌ℎ is the density of the hammer of carbon steel material (kg/m3), 𝑉ℎ is the volume of the hammer (m3) 2.1.10 Determination of the centrifugal force exerted by each hammer Centrifugal force exerted by the hammer is given using Eq. 10 extracted from the study of12] as follows: 𝐹𝑐 = 𝑁ℎ × 𝑀ℎ × 𝑟ℎ × 𝜔2ℎ (10) Where: 𝐹𝑐 is the centrifugal force exerted by the hammer (N), 𝑁ℎ is the number
principles of engineering. 2.1.1 Determination of the main shaft speed, 𝑵𝟐 The speed of the main shaft, as described by [12] is calculated using Eq. 1 𝑁1 𝐷1 = 𝑁2 𝐷2 (1) Where: 𝑁1 is the revolution of the smaller pulley (rpm), 𝑁2 is the revolution of the larger pulley or main shaft (rpm), 𝐷1 is the diameter of the driver pulley (mm), 𝐷2 is the diameter of the driven pulley (mm) 2.1.2 Determination of the velocity of the belt According to [12], the velocity of a belt when there is zero slip is determined using Eq. 2 𝑉 = 𝜋𝐷1𝑁1 = 𝜋𝐷2𝑁2 60 60 (2) 2.1.3 Torque transmitted to the main shaft The torque transmitted by the belt to the main shaft, according to [12], is obtained using Eq. 3 T=60p2πN (3) Where: T is the Twisting moment or Torque transmitted in (Nm), P is the Power transmitted to the hammer shaft (hp) 2.1.4 Power transmitted by each belt The relationship between the power transmitted by each belt and the appropriate number
of belts to be used according to [12] is given as in Eq. 4 as follows: n=Total power transmittedPower transmitted by each belt (4) Where: n represents the number of V- belts used 2.1.5 Determination of the Coefficient of increase of belt length and angle of contact of belts.
According to [12], the coefficient of increase of the belt length per unit force was determined using Eq. 5 𝑐 sin ∝ = 𝑅−𝑟 (5) Where: α is the coefficient of increase of the belt length per unit force in degrees (°), R is the radius of the shaft pulley (mm), r is the radius of the motor pulley (mm), C is the Centre distance between the two pulleys (mm) 2.1.6 Determination of the Belt Tension Power transmitted by each belt drive is obtained using Eq. 6 as given by [12] Khurmi and Gupta (2005): 𝑃 = 𝑇1 − 𝑇2 𝑉 × 𝑛 (6) Where: P is the power transmitted by each belt (w), 𝑇1 is the tension in the slack side (N), 𝑇2 is the tension in the tight side of the belt(N), V is the velocity of the belt drive (m/s), n is the number of belts used 2.1.7 Determination of the length of the V belt The length of the belt is obtained using Eq. 7 L=πr2+r1+2x+r2-r12x (7) Where: L is the Length of the belt (mm), x is the centre
end of the belt (mm), 𝑟2 is the radius of the pulleys on the driven end of the belt (mm) 2.1.8 Determination of the weight of the pulley mounted on the shaft The weight of the pulley is determined by using Eq. 8 𝑊𝑝 = 𝑉𝑝𝜌𝑝𝑔 (8) Where: 𝑉𝑝 is the volume of the pulley (m3), 𝜌𝑝 is the density of the pulley material (kg/m3), g is the acceleration due to gravity of the pulley (m/s2) 2.1.9 Determination of the mass of each hammer The mass of each hammer is determined by using Eq. 9, as described by [12]: 𝑀ℎ = 𝜌ℎ × 𝑉ℎ (9) Where: 𝑀ℎ is the mass of the hammer (kg), 𝜌ℎ is the density of the hammer of carbon steel material (kg/m3), 𝑉ℎ is the volume of the hammer (m3) 2.1.10 Determination of the centrifugal force exerted by each hammer Centrifugal force exerted by the hammer is given using Eq. 10 extracted from the study of12] as follows: 𝐹𝑐 = 𝑁ℎ × 𝑀ℎ × 𝑟ℎ × 𝜔2ℎ (10) Where: 𝐹𝑐 is the centrifugal force exerted by the hammer (N), 𝑁ℎ is the number
Online since: July 2013
Authors: Jian Wu, Tian Xiu Yu
Namely, the representation must accomplish the following three requirements: Present fine-grain scalability that allows progressivity and full adaptivity.
A number of approaches have been developed in order to improve TCP and TFRC over wireless networks [12] [6].
The goal of this representation is not to model a facade with high geometric accuracy, but rather to keep the main characteristics of the facade (such as color, building material, number of stories, number of windows per story, and primitive style) simple, and thereby obtain a compact representation.
This means that to reduce the impact of roundtrip delays, the client-side LOD selection process must update the local panorama with a minimum number of server requests.
The system splits the LODDT according to size parameters, such as the targeted number of levels in a packet, maximum size of a packet, and so on.
A number of approaches have been developed in order to improve TCP and TFRC over wireless networks [12] [6].
The goal of this representation is not to model a facade with high geometric accuracy, but rather to keep the main characteristics of the facade (such as color, building material, number of stories, number of windows per story, and primitive style) simple, and thereby obtain a compact representation.
This means that to reduce the impact of roundtrip delays, the client-side LOD selection process must update the local panorama with a minimum number of server requests.
The system splits the LODDT according to size parameters, such as the targeted number of levels in a packet, maximum size of a packet, and so on.
Online since: March 2024
Authors: Leo Van Cauter, Veerle Boel
In this paper, more than 20 mixtures of metakaolin/blast furnace slag alkali-activated mortar mixtures with a maximum grain size of 2.5 mm are investigated.
CO2 emissions from buildings operations have reached an all-time high of around 10 GtCO2, around a 5% increase from 2020 and 2% higher than the previous peak in 2019. [1] The world’s construction sector is contributing nearly 40% to global emissions, with the number of buildings being built increasing every passing year. [2] The production of each ton of cement releases up to 0.95 ton of CO2.
The naming of the mixtures includes the type of activator (S: sodium silicate solution; P: potassium silicate solution), the M.% of metakaolin in the precursor, and a numbering to distinguish between mixtures with different amount of water.
The strength results are checked on outliers according to the standard, and it is indicated with * in the tables in case the number of considered results had to be altered.
Conclusion The research presented in this paper investigated more than 20 mixtures of metakaolin/blast furnace slag alkali-activated mortars with a maximum grain size of 2.5 mm.
CO2 emissions from buildings operations have reached an all-time high of around 10 GtCO2, around a 5% increase from 2020 and 2% higher than the previous peak in 2019. [1] The world’s construction sector is contributing nearly 40% to global emissions, with the number of buildings being built increasing every passing year. [2] The production of each ton of cement releases up to 0.95 ton of CO2.
The naming of the mixtures includes the type of activator (S: sodium silicate solution; P: potassium silicate solution), the M.% of metakaolin in the precursor, and a numbering to distinguish between mixtures with different amount of water.
The strength results are checked on outliers according to the standard, and it is indicated with * in the tables in case the number of considered results had to be altered.
Conclusion The research presented in this paper investigated more than 20 mixtures of metakaolin/blast furnace slag alkali-activated mortars with a maximum grain size of 2.5 mm.
Online since: December 2010
Authors: Martin Selin
This is because the thermal conductivity is dependent on the movement of free
electrons, and therefore unfavourable growth directions and grain boundaries which impede the
electron movement will reduce the thermal conductivity.
(2) (3) Xi denotes the different key parameters and n their number. αi and βi are constants related to the key parameters and determine the influence of that specific parameter, i.e. size and sign. α0 and β0 are not related to any parameters but supply an initial value that is adjusted by the parameters and their constants.
(2) (3) Xi denotes the different key parameters and n their number. αi and βi are constants related to the key parameters and determine the influence of that specific parameter, i.e. size and sign. α0 and β0 are not related to any parameters but supply an initial value that is adjusted by the parameters and their constants.
Online since: January 2022
Authors: Christian La Borderie, Céline Perlot, Haissam El Ghoche, Rafik Isaam Abdallah, Hélène Carré
It is an illitic silty-clayey soil with a grain size distribution of 16.3% clay (<0.002 mm), 42.9% silt (0.002-0.063 mm), 40.4% sand (0.063-2 mm) and 0.4% gravel (>2 mm).
During the test, the number of instability events (sounds resulting from thermal instabilities) and their time and intensities were tracked.
The time, number and intensity of the occurring instability events were noted during the progress of the fire test and they are presented in Tab. 2.
Equalized samples at 75%RH showed a higher number of broken pieces (190 pieces, Tab. 3) relative to 24% mass.
It influenced the number and intensity of instability events and consequently the amount of damage and collapse the sample was exposed to. 3.
During the test, the number of instability events (sounds resulting from thermal instabilities) and their time and intensities were tracked.
The time, number and intensity of the occurring instability events were noted during the progress of the fire test and they are presented in Tab. 2.
Equalized samples at 75%RH showed a higher number of broken pieces (190 pieces, Tab. 3) relative to 24% mass.
It influenced the number and intensity of instability events and consequently the amount of damage and collapse the sample was exposed to. 3.
Online since: April 2021
Authors: Nandang Mufti, M. Tommy Hasan Abadi, Siti Zulaikah, Nurma Ari Sofa
Fig. 2a-2c illustrates the increase in grain agglomeration of the sample surface becomes irregular granules.
This ZnO reaction pattern is following the data model referring to the Crystallography Open Database (COD) number 9004182.
At the wave number 1250 cm-1, a vibration stretching of the C-N+ bond in the polaron structure is observed [20].
It is because the characterization tool used only works in the middle infrared wave number area (4000-200 cm-1) while the Au wave number area is outside the instrument wavenumber area [30].
In this case, it assumed that the increase in the deposition time of Au has an effect on the number of free electrons from the Au to the ZnO layer, where the high number of free electrons causes the Fermi level of ZnO to shift higher into the conduction band so that the bandgap widens.
This ZnO reaction pattern is following the data model referring to the Crystallography Open Database (COD) number 9004182.
At the wave number 1250 cm-1, a vibration stretching of the C-N+ bond in the polaron structure is observed [20].
It is because the characterization tool used only works in the middle infrared wave number area (4000-200 cm-1) while the Au wave number area is outside the instrument wavenumber area [30].
In this case, it assumed that the increase in the deposition time of Au has an effect on the number of free electrons from the Au to the ZnO layer, where the high number of free electrons causes the Fermi level of ZnO to shift higher into the conduction band so that the bandgap widens.
Online since: May 2022
Authors: S. El-Sayed, S.A. Sayed, Marwa Hafez
The spectroscopic properties of RuDPC complex is seemed to be dependent on its characteristics to the effect of radiation (FTIR), as a solar material in the application of this field; due to DPC is a photosensitive material, so that there are a number of optical applications which depend upon optically induced structure transition energy states for the complex.
Ruthenium (Ru) is one of the chemical elements, it has atomic number of 44 and its electronic configuration is [Kr] 4d7 5s1.
The SEM image of RuDPC shows the distribution of particles within the agglomerated cluster throughout the surface with fine grained structure.
The rate change in the FTIR spectroscopic analysis through the formation of new complex (RuDPC), such as (band shape, transmittance, rotational energy barrier, relaxation time,…) is mainly related to the number of ions that tolerate different energy states.
That is supported the basic spectroscopic properties of the new complex (RuDPC) is seemed to be based on its characteristic to the effect of radiation (FTIR), as a solar material in the application of this field, due to DPC is a photosensitive material, and the formation of the delocalized energy state in the new complex (RuDPC), so that there are a number of optical applications which depend upon optically induced structure transition energy states for the (RuDPC) complex.
Ruthenium (Ru) is one of the chemical elements, it has atomic number of 44 and its electronic configuration is [Kr] 4d7 5s1.
The SEM image of RuDPC shows the distribution of particles within the agglomerated cluster throughout the surface with fine grained structure.
The rate change in the FTIR spectroscopic analysis through the formation of new complex (RuDPC), such as (band shape, transmittance, rotational energy barrier, relaxation time,…) is mainly related to the number of ions that tolerate different energy states.
That is supported the basic spectroscopic properties of the new complex (RuDPC) is seemed to be based on its characteristic to the effect of radiation (FTIR), as a solar material in the application of this field, due to DPC is a photosensitive material, and the formation of the delocalized energy state in the new complex (RuDPC), so that there are a number of optical applications which depend upon optically induced structure transition energy states for the (RuDPC) complex.