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Online since: April 2019
Authors: Shahrom Mahmud, Naser Mahmoud Ahmed, Dauda Abubakar
The wet oxidation sample of NiO nanoparticle forms a grains diameter of about 25 – 34 nm with no pores (Fig 4a).
[AOH2+], [AOH] and AO- are the numbers of these sites per surface area.
Based on the well-known theory of site binding, the binding sites number residing on the sensing membrane could result to surface potential voltage changes between the electrolyte and the sensing layer interface which depend on pH at point of zero charge (pHpzc).
Based on the site binding model mentioned above, the surface potential voltage of NiO thin film between the sensing layer and the electrolytic pH solution interface can be expressed as [14]; . ψ=2.303kTqββ+1(pHpzc-pH) (8) where pHpzc= -log10(KAKB)12 is the pH value at the zero charge point of the sensing membrane, β=2q2NS(KBKA)12kTCDL is the sensitivity parameter, which depend on the density of surface hydroxyl groups and reflects the chemical sensitivity of the gate insulator, NS is the total number of surface sites per unit area, and KA and KB are acid and base equilibrium constants, respectively.
The sensitivity of dry oxidation based NiO membrane (54 mV/pH) was found to be relatively higher than that of wet oxidation based NiO membrane (48 mV/pH) due to the high crystallinity and surface to volume ratio properties of dry oxidation based NiO Nanostructured thin films, which provided higher number of sites and increased the number of exchangeable ions with the [H+] available in the electrolyte.
[AOH2+], [AOH] and AO- are the numbers of these sites per surface area.
Based on the well-known theory of site binding, the binding sites number residing on the sensing membrane could result to surface potential voltage changes between the electrolyte and the sensing layer interface which depend on pH at point of zero charge (pHpzc).
Based on the site binding model mentioned above, the surface potential voltage of NiO thin film between the sensing layer and the electrolytic pH solution interface can be expressed as [14]; . ψ=2.303kTqββ+1(pHpzc-pH) (8) where pHpzc= -log10(KAKB)12 is the pH value at the zero charge point of the sensing membrane, β=2q2NS(KBKA)12kTCDL is the sensitivity parameter, which depend on the density of surface hydroxyl groups and reflects the chemical sensitivity of the gate insulator, NS is the total number of surface sites per unit area, and KA and KB are acid and base equilibrium constants, respectively.
The sensitivity of dry oxidation based NiO membrane (54 mV/pH) was found to be relatively higher than that of wet oxidation based NiO membrane (48 mV/pH) due to the high crystallinity and surface to volume ratio properties of dry oxidation based NiO Nanostructured thin films, which provided higher number of sites and increased the number of exchangeable ions with the [H+] available in the electrolyte.
Online since: April 2008
Authors: Andriy O. Koval'chuk, Andriy Gusak, V.F. Mazanko, D.S. Gertsriken
They are as follows:
( )ηηηηηη
XXXXXX
X EcEczE +
= , (9)
() ()
[]
ηη
ηη
ηηη
η
η
BBBAAAABBA
V EcEcEcc
z
E
2
2
2
2
++⋅−= , (10)
where ηXYE - pair interaction energy of species X and Y, ηz - NN number in corresponding phase
and X denotes the another species relatively to X .
For the concentration change (of B-species) in plane n: 1 1 +→ →− −= nnnnn JJc& , [ ]nnn nnnnn nn cc cczJ →+ ++→+ +→ Γ−−Γ−= 1 11 1 1 )1( )1( , (11) where 1nnJ →+ is the net flux of B atoms from plane n to n+1 per lattice site, z is the number of NN sites in neighboring planes ( 3z = ), 1+→Γ nn is the frequency of exchange of B atom in plane n with A atom in plane n+1: −=Γ +→ +→ kT E nn nn 1 1 expν , (12) where 1+→nnE is a corresponding activation barrier.
nn o AB BB n n on AA AB n n o n E E E E zc zc z c E E zc zc z c +→ + + −+ = +− ++ +− ++ (13b) Here oz is the number of NN sites in the same plane (6oz = ), oE is a fixed saddle point energy for A-B exchange.
Let's assume that the stress relaxation has a nonuniform character: instead of redistribution within the crystal grain it is localized making such "overthrusts" of a lattice.
Here ν is a number of interstitials per site ( 3=ν - see Fig. 5), oz is the number of NN interstitial in the same plane (4=oz ), XYji→Γ - the frequency of displacement of atom Y in the plane j by X-interstitial from the plane i, X ji→Γ' - the frequency of X-interstitial jump from plane i to plane j.
For the concentration change (of B-species) in plane n: 1 1 +→ →− −= nnnnn JJc& , [ ]nnn nnnnn nn cc cczJ →+ ++→+ +→ Γ−−Γ−= 1 11 1 1 )1( )1( , (11) where 1nnJ →+ is the net flux of B atoms from plane n to n+1 per lattice site, z is the number of NN sites in neighboring planes ( 3z = ), 1+→Γ nn is the frequency of exchange of B atom in plane n with A atom in plane n+1: −=Γ +→ +→ kT E nn nn 1 1 expν , (12) where 1+→nnE is a corresponding activation barrier.
nn o AB BB n n on AA AB n n o n E E E E zc zc z c E E zc zc z c +→ + + −+ = +− ++ +− ++ (13b) Here oz is the number of NN sites in the same plane (6oz = ), oE is a fixed saddle point energy for A-B exchange.
Let's assume that the stress relaxation has a nonuniform character: instead of redistribution within the crystal grain it is localized making such "overthrusts" of a lattice.
Here ν is a number of interstitials per site ( 3=ν - see Fig. 5), oz is the number of NN interstitial in the same plane (4=oz ), XYji→Γ - the frequency of displacement of atom Y in the plane j by X-interstitial from the plane i, X ji→Γ' - the frequency of X-interstitial jump from plane i to plane j.
Online since: February 2014
Authors: Ding Guo Huang, Xing Wu Hou, Hang Zheng Li, Hai Feng Chen, Xuan Peng
China has a long history of coal mining; there are a large number of discarded mines owing to resource extinct so far.
Namely, after overlying roof rock stratum caving itself directly, broken rock layers fill up the gob and gradually close-grained with the basic roof slowly sinking, thereby forming a bottom to up caving zone, fractured zone and bending zone.
In addition, a large number of abandoned underground laneways and chambers retain considerable volume.
For abandoned mine storing CO2, there are large numbers of geological exploration work in the process of mines exploration and production, and accumulate rich geological data.
(3)The relatively closed of each field can form a number of independent storage areas in a mining area, which is beneficial for the flexible management of CO2 storage and reduces the risk of large-scale sequestration
Namely, after overlying roof rock stratum caving itself directly, broken rock layers fill up the gob and gradually close-grained with the basic roof slowly sinking, thereby forming a bottom to up caving zone, fractured zone and bending zone.
In addition, a large number of abandoned underground laneways and chambers retain considerable volume.
For abandoned mine storing CO2, there are large numbers of geological exploration work in the process of mines exploration and production, and accumulate rich geological data.
(3)The relatively closed of each field can form a number of independent storage areas in a mining area, which is beneficial for the flexible management of CO2 storage and reduces the risk of large-scale sequestration
Online since: December 2024
Authors: Oksana Melnikova, Valentina Iurchenko, Natalia Teliura
Suction of sewage liquid in a number of studies was excluded by hanging concrete samples in nets on the arch.
We have identified a number of water insoluble, but extractable into solution by organic solvents (lipid-like) compounds, in the products of microbiological corrosion of concrete (Fig. 2).
The formation of phospholipids and the role of this metabolite in adsorption of bacterial cells on mineral grains, dissolution of sulfur and protection of bacteria from toxicants were reported in studies of T.ferroxidans [21].
Among the organic substances formed by microbiocenoses on the arch part of collectors: phospholipids, as well as phthalic acid esters, alkanes (paraffins) with the number of carbon atoms in the molecule up to C36, alcohols, aromatic compounds. 4.
Methods for determination of acid number (ISO 660:1996, NEQ).
We have identified a number of water insoluble, but extractable into solution by organic solvents (lipid-like) compounds, in the products of microbiological corrosion of concrete (Fig. 2).
The formation of phospholipids and the role of this metabolite in adsorption of bacterial cells on mineral grains, dissolution of sulfur and protection of bacteria from toxicants were reported in studies of T.ferroxidans [21].
Among the organic substances formed by microbiocenoses on the arch part of collectors: phospholipids, as well as phthalic acid esters, alkanes (paraffins) with the number of carbon atoms in the molecule up to C36, alcohols, aromatic compounds. 4.
Methods for determination of acid number (ISO 660:1996, NEQ).
Online since: January 2012
Authors: Bao Wei Li, Hui Ping Ren, Yang Huan Zhang, Zhong Hui Hou, Dong Liang Zhao, Zai Guang Pang
It is very evident that the as-cast alloys exhibit a typical dendrite structure, and the substitution incurs the notable refinement of the grains of the as-cast alloys.
The evolution of the Rn values of the as-spun (25 m/s) alloys with the cycle number is described in Fig. 4.
The activation capability was characterized by the number of charge-discharge required for attaining the greatest discharge capacity through a charge-discharge cycle at a constant current density.
Fig. 6 presents the cycle number dependence of the discharge capacities of the as-spun (25 m/s) alloys.
It is Fig. 6 Evolution of the discharge capacity of the as-spun (25 m/s) alloys with the cycle number: (a) M=Cu, (b) M=Co Fig. 7 Evolution of the maximum discharge capacity of the as-spun (25 m/s) alloys with M content evident that the HRD values of the as-spun (25 m/s) alloys visibly grow with rising M (M=Cu, Co) content.
The evolution of the Rn values of the as-spun (25 m/s) alloys with the cycle number is described in Fig. 4.
The activation capability was characterized by the number of charge-discharge required for attaining the greatest discharge capacity through a charge-discharge cycle at a constant current density.
Fig. 6 presents the cycle number dependence of the discharge capacities of the as-spun (25 m/s) alloys.
It is Fig. 6 Evolution of the discharge capacity of the as-spun (25 m/s) alloys with the cycle number: (a) M=Cu, (b) M=Co Fig. 7 Evolution of the maximum discharge capacity of the as-spun (25 m/s) alloys with M content evident that the HRD values of the as-spun (25 m/s) alloys visibly grow with rising M (M=Cu, Co) content.
Online since: March 2016
Authors: Yuriy Nikolaevich Kulchin, Aleksandr A. Kuchmizhak, Oleg B. Vitrik, Stanislav O. Gurbatov
Diffusely transmitting object (diffusor), an optically rough 2-mm thick quartz plate with the average grain size of 1 µm, was used to forming a speckle pattern.
It can be seen that the portion of nanojets (as well as microbumps) significantly increased in the structures total number, and through holes portion decreased to 1%.
However, contribution of the great number of individual nanostructures to the total scattering signal is Figure 3.
To save the stochastic nature of the nanostructures location the displacement step is selected by a random number generator.
The figures show that the nanojets quantity increases proportionally to the number of pulses and the presence of microbumps on the surface doesn't hinder the further formation of nanojets on their place.
It can be seen that the portion of nanojets (as well as microbumps) significantly increased in the structures total number, and through holes portion decreased to 1%.
However, contribution of the great number of individual nanostructures to the total scattering signal is Figure 3.
To save the stochastic nature of the nanostructures location the displacement step is selected by a random number generator.
The figures show that the nanojets quantity increases proportionally to the number of pulses and the presence of microbumps on the surface doesn't hinder the further formation of nanojets on their place.
Online since: October 2018
Authors: Alexander D. Razmyshlyaev, Elena V. Lavrova, Marina V. Ahieieva
Such magnetic characteristics of the indicated bodies as B(H) and m(H) depend on the chemical composition of alloys based on iron, microstructure and grain sizes and they are not linear.
A magnetizing winding with a number of turns W1 and a measuring winding with a number of turns W2 were wound on the researched sample, which had the form of a torus.
Windings W1 and W2 are made of copper insulated wire with a diameter of 0.3...0.5 mm, the number of turns was W1 = 150…350; W2 = 75.
If we take a torus with an average diameter dav with a slot of width b (Fig. 3a) and place a winding uniformly on it with the total number of turns W and flow through it a constant current I, then the magnetic permeability in the slot is equal to B.
The windings were reeled (uniformly) from copper insulated wires 1.2 mm in diameter with a number of turns W = 50.
A magnetizing winding with a number of turns W1 and a measuring winding with a number of turns W2 were wound on the researched sample, which had the form of a torus.
Windings W1 and W2 are made of copper insulated wire with a diameter of 0.3...0.5 mm, the number of turns was W1 = 150…350; W2 = 75.
If we take a torus with an average diameter dav with a slot of width b (Fig. 3a) and place a winding uniformly on it with the total number of turns W and flow through it a constant current I, then the magnetic permeability in the slot is equal to B.
The windings were reeled (uniformly) from copper insulated wires 1.2 mm in diameter with a number of turns W = 50.
Online since: December 2014
Authors: Dong Feng Li, Jian Tong Zhang
Researchers had used different methods to model asphalt mixture individual strain components including mechanical elements such as Burger-type and Maxwell-type elements; power law functions of stress, time, and number of load repetitions; and Perzyna’s theory of viscoplasticity.
Specially, aggregate shape and angularity were found to be amongst the most important parameters that affect asphalt performance, as they have a strong influence on the way grains make contact and interlock.
In this model the asphalt mixture specimen is reconstructed with a given number of aggregates coated with asphalt cement.
The number of viscoelastic elements for a given specimen depends on the number of asphalt-coated aggregate contacts.
The DSC can be implemented in two and three dimensional finite-element procedures, which provide unique and novel approaches for pavement engineering and allow static, repetitive, and dynamic loads including elastic, plastic, creep, microcracking leading to fracture and failure [30, 31]. 3 Summary and Conclusion In this study, many microstructure-based computational methods, which had done by a number of researchers, for predicting micromechanical behavior of asphalt mixtures are presented.
Specially, aggregate shape and angularity were found to be amongst the most important parameters that affect asphalt performance, as they have a strong influence on the way grains make contact and interlock.
In this model the asphalt mixture specimen is reconstructed with a given number of aggregates coated with asphalt cement.
The number of viscoelastic elements for a given specimen depends on the number of asphalt-coated aggregate contacts.
The DSC can be implemented in two and three dimensional finite-element procedures, which provide unique and novel approaches for pavement engineering and allow static, repetitive, and dynamic loads including elastic, plastic, creep, microcracking leading to fracture and failure [30, 31]. 3 Summary and Conclusion In this study, many microstructure-based computational methods, which had done by a number of researchers, for predicting micromechanical behavior of asphalt mixtures are presented.
Online since: December 2023
Authors: Srikrishna Bhaskar Rao, K. Venkadeshwaran, Y. Naidu Shivaprasad
Henry P et al. [35] shown that the coaxial wire cladding technique is better as compared to off-pivot wire cladding technique, through arrangement of the wire to the laser pillar, freedom of the movement course and a diminished number of controlling boundaries.
3.
By adding powder particles like CeO2 and Y2O3, it enhances the coating properties by refining the grain structures [56].
Peng-Xiang Zhang, Hong Yan, January 2021. 316L stainless steel TiC composite Obtain homogeneity in the carbide distribution and improve mechanical properties by grain refinement and carbide formation.
August 2020. 304 stainless steel Aerosol particles The interaction of water on coating formation, grain morphology and size, microstructure and corrosion performance was investigated Fu Y, Guo N, Zhou C October 2020.
Mingming Ma, Zeming Wang Dec 2016. 304 Stainless steel 316L stainless steel powders with WC particles Microstructure of the cladded zone is checked, columnar dendrites, cluster of cells, equiaxed grain size of the structure is observed.
By adding powder particles like CeO2 and Y2O3, it enhances the coating properties by refining the grain structures [56].
Peng-Xiang Zhang, Hong Yan, January 2021. 316L stainless steel TiC composite Obtain homogeneity in the carbide distribution and improve mechanical properties by grain refinement and carbide formation.
August 2020. 304 stainless steel Aerosol particles The interaction of water on coating formation, grain morphology and size, microstructure and corrosion performance was investigated Fu Y, Guo N, Zhou C October 2020.
Mingming Ma, Zeming Wang Dec 2016. 304 Stainless steel 316L stainless steel powders with WC particles Microstructure of the cladded zone is checked, columnar dendrites, cluster of cells, equiaxed grain size of the structure is observed.
Online since: August 2013
Authors: Guang Hui Li, Li Hua Zhang, Jiang Wei Zhao, Bin Li
The signals were transmitted to the signal conditioning part to complete the signal amplification and active filter, then DAQ will complete the signal pickup and the set of relevant parameters (Acquisition channel, sample rate, sample numbers period, etc), The data will be further processed and displayed on the software of the measurement and control system based on LabVIEW .
sample rate or sample numbers, and so on) (2)Synchronous acquisition of motor input speed (n) and motor input torque (T) through the data acquisition equipment, then save as LABVIEW data type
The sample rate and the sample numbers are 1000), as is shown in Fig.6.
Secondly, assuming that the given motor speed was 2000 r/min and the signal input torque was (The sample rate and the sample number are 1000),the preservation of data recovery torque signal and motor power consumption information were shown in Fig.8 and Fig.9.
Test of Near Infrared Detector for Grain Component Based on Virtual Instrument[J].
sample rate or sample numbers, and so on) (2)Synchronous acquisition of motor input speed (n) and motor input torque (T) through the data acquisition equipment, then save as LABVIEW data type
The sample rate and the sample numbers are 1000), as is shown in Fig.6.
Secondly, assuming that the given motor speed was 2000 r/min and the signal input torque was (The sample rate and the sample number are 1000),the preservation of data recovery torque signal and motor power consumption information were shown in Fig.8 and Fig.9.
Test of Near Infrared Detector for Grain Component Based on Virtual Instrument[J].