Recycled waste tires when mixed with soil can play an important role as lightweight materials in retaining walls and embankments, machine foundations and railroad track beds in seismic zones. Having high damping chara...Recycled waste tires when mixed with soil can play an important role as lightweight materials in retaining walls and embankments, machine foundations and railroad track beds in seismic zones. Having high damping characteristic, rubbers can be used as either soil alternative or mixed with soil to reduce vibration when seismic loads are of great concern. Therefore, the objective of this work was to evaluate the dynamic properties of such mixtures prior to practical applications. To this reason, torsional resonant column and dynamic triaxial experiments were carried out and the effect of the important parameters like rubber content and ratio of mean grain size of rubber solids versus soil solids(D50,r/D50,s) on dynamic response of mixtures in a range of low to high shearing strain amplitude from about 4×10-4% to 2.7% were investigated. Considering engineering applications, specimens were prepared almost at the maximum dry density and optimum moisture content to model a mixture layer above the ground water table and in low precipitation region. The results show that tire inclusion significantly reduces the shear modulus and increases the damping ratio of the mixtures. Also decrease in D50,r/D50,s causes the mixture to exhibit more rubber-like behavior. Finally, normalized shear modulus versus shearing strain amplitude curve was proposed for engineering practice.展开更多
Objective:To determine lactic acid bacteria's capability to enhance the process of binding and isolating aflatoxin B1 and to utilize such lactic acid bacteria as a food supplement or probiotic products for prevent...Objective:To determine lactic acid bacteria's capability to enhance the process of binding and isolating aflatoxin B1 and to utilize such lactic acid bacteria as a food supplement or probiotic products for preventing absorption of aflatoxin Bl in human and animal bodies.Methods:In the present research,the bacteria were isolated from five different sources.For surveying the capability of the bacteria in isolating aflatoxin Bl,ELISA method was implemented,and for identifying the resultant strains through 16S rRNA sequencing method,universal primers were applied.Results:Among the strains which were isolated,two strains of Lactobacillus pentosus and Lactobacillus beveris exhibited the capability of absorbing and isolating aflatoxin Bl by respectively absorbing and discharging 17.4%and 34.7%of the aforementioned toxin existing in the experiment solution.Conclusions:Strains of Lactobacillus pentosus and Lactobacillus beveris were isolated from human feces and local milk samples,respectively.And both strains has the ability to isolate or bind with aflatoxin Bl.展开更多
Magnesium(Mg)alloys are gaining great consideration as body implant materials due to their high biodegradability and biocompatibility.However,they suffer from low corrosion resistance and antibacterial activity.In thi...Magnesium(Mg)alloys are gaining great consideration as body implant materials due to their high biodegradability and biocompatibility.However,they suffer from low corrosion resistance and antibacterial activity.In this research,semi-powder metallurgy followed by hot extrusion was utilized to produce the magnesium oxide@graphene nanosheets/magnesium(MgO@GNS/Mg)composite to improve mechanical,corrosion and cytocompatibility characteristics.Investigations have revealed that the incorporation of MgO@GNS nanohybrids into Mg-based composite enhanced microhardness and compressive strength.In vitro,osteoblast cell culture tests show that using MgO@GNS nanohybrid fillers enhances osteoblast adhesion and apatite mineralization.The presence of MgO@GNS nanoparticles in the composites decreased the opening defects,micro-cracks and micro-pores of the composites thus preventing the penetration of the corrosive solution into the matrix.Studies demonstrated that the MgO@GNS/Mg composite possesses excellent antibacterial properties because of the combination of the release of MgO and physical damage to bacterium membranes caused by the sharp edges of graphene nanosheets that can effectively damage the cell wall thereby facilitating penetration into the bacterial lipid bilayer.Therefore,the MgO@GNS/Mg composite with high mechanical strength,antibacterial activity and corrosion resistance is considered to be a promising material for load-bearing implant applications.展开更多
This study aims to evaluate the solar and wind energy potential across Razavi Khorasan Province,Iran,with a specific focus on the Khaf region.A preliminary assessment of mean solar radiation,mean wind speeds,and Weibu...This study aims to evaluate the solar and wind energy potential across Razavi Khorasan Province,Iran,with a specific focus on the Khaf region.A preliminary assessment of mean solar radiation,mean wind speeds,and Weibull distribution parameters was conducted for different towns and zones within the province.The findings showed that Khaf has favorable characteristics for further analysis.The solar and wind energy metrics examined include global horizontal irradiance,clearness index,wind rose patterns,and turbulence intensity.At a height of 40 m,Khaf’s wind power density reached 1650 W/m^(2),indicating exceptional wind energy generation potential.Additionally,Khaf received an average annual solar radiation of 2046 kW·h/m^(2),representing significant solar energy potential.Harnessing these substantial renewable resources in Khaf could allow Razavi Khorasan Province to reduce reliance on fossil fuels,improve energy sustainability,and mitigate climate change impacts.This research contributes an in-depth assessment of Razavi Khorasan's solar and wind energy potential,particularly for the promising Khaf region.Further work may examine optimal sites for renewable energy projects and grid integration strategies to leverage these resources.展开更多
Computational fluid dynamics(CFD)provides a powerful tool for investigating complicated fluid flows.This paper aims to study the applicability of CFD in the preliminary design of linear and nonlinear fluid viscous dam...Computational fluid dynamics(CFD)provides a powerful tool for investigating complicated fluid flows.This paper aims to study the applicability of CFD in the preliminary design of linear and nonlinear fluid viscous dampers.Two fluid viscous dampers were designed based on CFD models.The first device was a linear viscous damper with straight orifices.The second was a nonlinear viscous damper containing a one-way pressure-responsive valve inside its orifices.Both dampers were detailed based on CFD simulations,and their internal fluid flows were investigated.Full-scale specimens of both dampers were manufactured and tested under dynamic loads.According to the tests results,both dampers demonstrate stable cyclic behaviors,and as expected,the nonlinear damper generally tends to dissipate more energy compared to its linear counterpart.Good compatibility was achieved between the experimentally measured damper force-velocity curves and those estimated from CFD analyses.Using a thermography camera,a rise in temperature of the dampers was measured during the tests.It was found that output force of the manufactured devices was virtually independent of temperature even during long duration loadings.Accordingly,temperature dependence can be ignored in CFD models,because a reliable temperature compensator mechanism was used(or intended to be used)by the damper manufacturer.展开更多
Photons that are entangled or correlated in orbital angular momentum have been extensively used for remote sensing,object identification and imaging.It has recently been demonstrated that intensity fluctuations give r...Photons that are entangled or correlated in orbital angular momentum have been extensively used for remote sensing,object identification and imaging.It has recently been demonstrated that intensity fluctuations give rise to the formation of correlations in the orbital angular momentum components and angular positions of random light.Here we demonstrate that the spatial signatures and phase information of an object with rotational symmetries can be identified using classical orbital angular momentum correlations in random light.The Fourier components imprinted in the digital spiral spectrum of the object,as measured through intensity correlations,unveil its spatial and phase information.Sharing similarities with conventional compressive sensing protocols that exploit sparsity to reduce the number of measurements required to reconstruct a signal,our technique allows sensing of an object with fewer measurements than other schemes that use pixel-by-pixel imaging.One remarkable advantage of our technique is that it does not require the preparation of fragile quantum states of light and operates at both low-and high-light levels.In addition,our technique is robust against environmental noise,a fundamental feature of any realistic scheme for remote sensing.展开更多
Ground-motion Intensity Measures (IMs) are used to quantify the strength of ground motions and evaluate the response of structures. IMs act as a link between seismic demand and seismic hazard analysis and therefore, h...Ground-motion Intensity Measures (IMs) are used to quantify the strength of ground motions and evaluate the response of structures. IMs act as a link between seismic demand and seismic hazard analysis and therefore, have a key role in performance-based earthquake engineering. Many studies have been carried out on the determination of suitable IMs in terms of effi ciency, suffi ciency and scaling robustness. The majority of these investigations focused on ordinary structures such as buildings and bridges, and only a few were about buried pipelines. In the current study, the optimal IMs for predicting the seismic demand of continuous buried steel pipelines under near-fi eld pulse-like ground motion records is investigated. Incremental dynamic analysis is performed using twenty ground motion records. Using the results of the regression analysis, the optimality of 23 potential IMs are studied. It is concluded that specifi c energy density (SED) followed by VSI[ω1(PGD+RMSd )] are the optimal IMs based on effi ciency, suffi ciency and scaling robustness for seismic response evaluation of buried pipelines under near-fi eld ground motions.展开更多
The combination of isatin, barbituric acid, and cyclohexane-1,3-dione derivatives in the presence of alum （KAI（SO4）2· 12H2O） as a catalyst for 15 min was found to be a suitable and efficient method for the sy...The combination of isatin, barbituric acid, and cyclohexane-1,3-dione derivatives in the presence of alum （KAI（SO4）2· 12H2O） as a catalyst for 15 min was found to be a suitable and efficient method for the synthesis of spiro[chromeno[2,3-d]pyrimidine-5,3＇-indoline]-tetraones.展开更多
Metabasite refers to metamorphosed basalts and other mafic igneous rocks (rich in iron and magnesium). When a mafic igneous rock is subjected to new pressure and temperature conditions during metamorphism, these chemi...Metabasite refers to metamorphosed basalts and other mafic igneous rocks (rich in iron and magnesium). When a mafic igneous rock is subjected to new pressure and temperature conditions during metamorphism, these chemical components will rearrange themselves to form new minerals. Metabasites can be found in many metamorphic belts including Sanandaj-Sirjan metamorphic belt of Iran. The study area is a Tanbour metamorphic complex in Eastern of Sirjan city, which is geologically located at the Sanandaj-Sirjan metamorphic belt in Southern Iran. Metabasite in this complex consists of greenschist, epidote amphibolite and amphibolite. Amphibole and plagioclase are the main minerals in the greenschist and amphibolite, and the a secondary mineral in some micaschist seen in the study area. The electron microprobe analysis was done on this mineralization in greenschist, epidote amphibolite and amphibolite, which showed that the amphiboles in greenschist was a member of the calcic group and Actinolite type, and the amphiboles in epidote amphibolite was a member of the calcic group and these amphiboles were tschermakite up to Ferro-Tschermakite + Ferro-Hornblende type. The amphibole in amphibolite is a member of the calcic group and this amphibole is Magnesio-Hornblende type. The plagioclases in the greenschist is pure albite (An 3.29 - 3.6), and in the epidote amphibolite is oligoclase (An 19.5 - 24.2), while in the amphibolites is oligoclase (An 16.9 - 26.6). The estimated P–T conditions are in favor of their metamorphism under epidote amphibolite (550°C and 8 kbar) and amphibolite (611°C - 652° Cand 10.5 kbar) facies.展开更多
A four-component reaction in the presence of Alum [KAl（SO4）2·12H2O] as an inexpensive and reusable catalyst using the ionic liquid as an effective green reaction media is reported.
Synchronization of neurons plays an important role in vision, movement and memory. However, many neurological disorders such as epilepsies, Parkinson disease and essen- tial tremor are related to excessive synchroniza...Synchronization of neurons plays an important role in vision, movement and memory. However, many neurological disorders such as epilepsies, Parkinson disease and essen- tial tremor are related to excessive synchronization of neurons. In the line of therapy, stimulations to these pathologically synchronized neurons should be capable of breaking synchrony. As the first step of designing an effective stimulation, we consider desynchro- nization problem of coupled limit-cycle oscillators ensemble. First, the desynchronization problem is redefined in a nonlinear output regulation framework. Then, we design an output regulator （stimulation） which forces limit-cycle oscillators to track exogenous sinusoidal references with different phases. The proposed stimulation is robust against variations of oscillators＇ frequencies. Mathematical analysis and simulation results reveal the efficiency of the proposed technique.展开更多
The purpose of this work is to find new soliton solutions of the complex Ginzburg–Landau equation(GLE)with Kerr law non-linearity.The considered equation is an imperative nonlinear partial differential equation(PDE)i...The purpose of this work is to find new soliton solutions of the complex Ginzburg–Landau equation(GLE)with Kerr law non-linearity.The considered equation is an imperative nonlinear partial differential equation(PDE)in the field of physics.The applications of complex GLE can be found in optics,plasma and other related fields.The modified extended tanh technique with Riccati equation is applied to solve the Complex GLE.The results are presented under a suitable choice for the values of parameters.Figures are shown using the three and two-dimensional plots to represent the shape of the solution in real,and imaginary parts in order to discuss the similarities and difference between them.The graphical representation of the results depicts the typical behavior of soliton solutions.The obtained soliton solutions are of different forms,such as,hyperbolic and trigonometric functions.The results presented in this paper are novel and reported first time in the literature.Simulation results establish the validity and applicability of the suggested technique for the complex GLE.The suggested method with symbolic computational software such as,Mathematica and Maple,is proven as an effective way to acquire the soliton solutions of nonlinear partial differential equations(PDEs)as well as complex PDEs.展开更多
In this paper, we have studied electronic properties of a two-electron quantum dot using Tietz confining potential in the presence of an external magnetic field. In this regard, we have applied diagonalization procedu...In this paper, we have studied electronic properties of a two-electron quantum dot using Tietz confining potential in the presence of an external magnetic field. In this regard, we have applied diagonalization procedure of Hamilonian matrix. We have calculated singlet-triplet ground state transitions as a function of the magnetic field. The obtained results show that the dot size of the Tietz potential has an important role in the ground state transition. The singlet-triplet transition of the ground state shifts towards lower magnetic field when the quantum size increases. Our results yield much less transitions than that of previous results [R.G. Nazmitdinov, N.S. Simonovic, and M.J. Rost, Phys.Rev. B 65(2002) 155307].展开更多
文摘Recycled waste tires when mixed with soil can play an important role as lightweight materials in retaining walls and embankments, machine foundations and railroad track beds in seismic zones. Having high damping characteristic, rubbers can be used as either soil alternative or mixed with soil to reduce vibration when seismic loads are of great concern. Therefore, the objective of this work was to evaluate the dynamic properties of such mixtures prior to practical applications. To this reason, torsional resonant column and dynamic triaxial experiments were carried out and the effect of the important parameters like rubber content and ratio of mean grain size of rubber solids versus soil solids(D50,r/D50,s) on dynamic response of mixtures in a range of low to high shearing strain amplitude from about 4×10-4% to 2.7% were investigated. Considering engineering applications, specimens were prepared almost at the maximum dry density and optimum moisture content to model a mixture layer above the ground water table and in low precipitation region. The results show that tire inclusion significantly reduces the shear modulus and increases the damping ratio of the mixtures. Also decrease in D50,r/D50,s causes the mixture to exhibit more rubber-like behavior. Finally, normalized shear modulus versus shearing strain amplitude curve was proposed for engineering practice.
基金Supported by Razi Vaccine And Serum Research Institute,Arak Branch,Iran(Grant No.TUMS/CMBRC-89-001)
文摘Objective:To determine lactic acid bacteria's capability to enhance the process of binding and isolating aflatoxin B1 and to utilize such lactic acid bacteria as a food supplement or probiotic products for preventing absorption of aflatoxin Bl in human and animal bodies.Methods:In the present research,the bacteria were isolated from five different sources.For surveying the capability of the bacteria in isolating aflatoxin Bl,ELISA method was implemented,and for identifying the resultant strains through 16S rRNA sequencing method,universal primers were applied.Results:Among the strains which were isolated,two strains of Lactobacillus pentosus and Lactobacillus beveris exhibited the capability of absorbing and isolating aflatoxin Bl by respectively absorbing and discharging 17.4%and 34.7%of the aforementioned toxin existing in the experiment solution.Conclusions:Strains of Lactobacillus pentosus and Lactobacillus beveris were isolated from human feces and local milk samples,respectively.And both strains has the ability to isolate or bind with aflatoxin Bl.
文摘Magnesium(Mg)alloys are gaining great consideration as body implant materials due to their high biodegradability and biocompatibility.However,they suffer from low corrosion resistance and antibacterial activity.In this research,semi-powder metallurgy followed by hot extrusion was utilized to produce the magnesium oxide@graphene nanosheets/magnesium(MgO@GNS/Mg)composite to improve mechanical,corrosion and cytocompatibility characteristics.Investigations have revealed that the incorporation of MgO@GNS nanohybrids into Mg-based composite enhanced microhardness and compressive strength.In vitro,osteoblast cell culture tests show that using MgO@GNS nanohybrid fillers enhances osteoblast adhesion and apatite mineralization.The presence of MgO@GNS nanoparticles in the composites decreased the opening defects,micro-cracks and micro-pores of the composites thus preventing the penetration of the corrosive solution into the matrix.Studies demonstrated that the MgO@GNS/Mg composite possesses excellent antibacterial properties because of the combination of the release of MgO and physical damage to bacterium membranes caused by the sharp edges of graphene nanosheets that can effectively damage the cell wall thereby facilitating penetration into the bacterial lipid bilayer.Therefore,the MgO@GNS/Mg composite with high mechanical strength,antibacterial activity and corrosion resistance is considered to be a promising material for load-bearing implant applications.
文摘This study aims to evaluate the solar and wind energy potential across Razavi Khorasan Province,Iran,with a specific focus on the Khaf region.A preliminary assessment of mean solar radiation,mean wind speeds,and Weibull distribution parameters was conducted for different towns and zones within the province.The findings showed that Khaf has favorable characteristics for further analysis.The solar and wind energy metrics examined include global horizontal irradiance,clearness index,wind rose patterns,and turbulence intensity.At a height of 40 m,Khaf’s wind power density reached 1650 W/m^(2),indicating exceptional wind energy generation potential.Additionally,Khaf received an average annual solar radiation of 2046 kW·h/m^(2),representing significant solar energy potential.Harnessing these substantial renewable resources in Khaf could allow Razavi Khorasan Province to reduce reliance on fossil fuels,improve energy sustainability,and mitigate climate change impacts.This research contributes an in-depth assessment of Razavi Khorasan's solar and wind energy potential,particularly for the promising Khaf region.Further work may examine optimal sites for renewable energy projects and grid integration strategies to leverage these resources.
文摘Computational fluid dynamics(CFD)provides a powerful tool for investigating complicated fluid flows.This paper aims to study the applicability of CFD in the preliminary design of linear and nonlinear fluid viscous dampers.Two fluid viscous dampers were designed based on CFD models.The first device was a linear viscous damper with straight orifices.The second was a nonlinear viscous damper containing a one-way pressure-responsive valve inside its orifices.Both dampers were detailed based on CFD simulations,and their internal fluid flows were investigated.Full-scale specimens of both dampers were manufactured and tested under dynamic loads.According to the tests results,both dampers demonstrate stable cyclic behaviors,and as expected,the nonlinear damper generally tends to dissipate more energy compared to its linear counterpart.Good compatibility was achieved between the experimentally measured damper force-velocity curves and those estimated from CFD analyses.Using a thermography camera,a rise in temperature of the dampers was measured during the tests.It was found that output force of the manufactured devices was virtually independent of temperature even during long duration loadings.Accordingly,temperature dependence can be ignored in CFD models,because a reliable temperature compensator mechanism was used(or intended to be used)by the damper manufacturer.
基金support from the program of the China Scholarship Council(no.201506210145)the support from the National Natural Science Foundation of China,no.11504337+1 种基金the partial support from the Natural Science Foundation of China under Grant nos 11175094 and 91221205the National Basic Research Program of China under Grant no.2015CB921002。
文摘Photons that are entangled or correlated in orbital angular momentum have been extensively used for remote sensing,object identification and imaging.It has recently been demonstrated that intensity fluctuations give rise to the formation of correlations in the orbital angular momentum components and angular positions of random light.Here we demonstrate that the spatial signatures and phase information of an object with rotational symmetries can be identified using classical orbital angular momentum correlations in random light.The Fourier components imprinted in the digital spiral spectrum of the object,as measured through intensity correlations,unveil its spatial and phase information.Sharing similarities with conventional compressive sensing protocols that exploit sparsity to reduce the number of measurements required to reconstruct a signal,our technique allows sensing of an object with fewer measurements than other schemes that use pixel-by-pixel imaging.One remarkable advantage of our technique is that it does not require the preparation of fragile quantum states of light and operates at both low-and high-light levels.In addition,our technique is robust against environmental noise,a fundamental feature of any realistic scheme for remote sensing.
文摘Ground-motion Intensity Measures (IMs) are used to quantify the strength of ground motions and evaluate the response of structures. IMs act as a link between seismic demand and seismic hazard analysis and therefore, have a key role in performance-based earthquake engineering. Many studies have been carried out on the determination of suitable IMs in terms of effi ciency, suffi ciency and scaling robustness. The majority of these investigations focused on ordinary structures such as buildings and bridges, and only a few were about buried pipelines. In the current study, the optimal IMs for predicting the seismic demand of continuous buried steel pipelines under near-fi eld pulse-like ground motion records is investigated. Incremental dynamic analysis is performed using twenty ground motion records. Using the results of the regression analysis, the optimality of 23 potential IMs are studied. It is concluded that specifi c energy density (SED) followed by VSI[ω1(PGD+RMSd )] are the optimal IMs based on effi ciency, suffi ciency and scaling robustness for seismic response evaluation of buried pipelines under near-fi eld ground motions.
文摘The combination of isatin, barbituric acid, and cyclohexane-1,3-dione derivatives in the presence of alum （KAI（SO4）2· 12H2O） as a catalyst for 15 min was found to be a suitable and efficient method for the synthesis of spiro[chromeno[2,3-d]pyrimidine-5,3＇-indoline]-tetraones.
文摘Metabasite refers to metamorphosed basalts and other mafic igneous rocks (rich in iron and magnesium). When a mafic igneous rock is subjected to new pressure and temperature conditions during metamorphism, these chemical components will rearrange themselves to form new minerals. Metabasites can be found in many metamorphic belts including Sanandaj-Sirjan metamorphic belt of Iran. The study area is a Tanbour metamorphic complex in Eastern of Sirjan city, which is geologically located at the Sanandaj-Sirjan metamorphic belt in Southern Iran. Metabasite in this complex consists of greenschist, epidote amphibolite and amphibolite. Amphibole and plagioclase are the main minerals in the greenschist and amphibolite, and the a secondary mineral in some micaschist seen in the study area. The electron microprobe analysis was done on this mineralization in greenschist, epidote amphibolite and amphibolite, which showed that the amphiboles in greenschist was a member of the calcic group and Actinolite type, and the amphiboles in epidote amphibolite was a member of the calcic group and these amphiboles were tschermakite up to Ferro-Tschermakite + Ferro-Hornblende type. The amphibole in amphibolite is a member of the calcic group and this amphibole is Magnesio-Hornblende type. The plagioclases in the greenschist is pure albite (An 3.29 - 3.6), and in the epidote amphibolite is oligoclase (An 19.5 - 24.2), while in the amphibolites is oligoclase (An 16.9 - 26.6). The estimated P–T conditions are in favor of their metamorphism under epidote amphibolite (550°C and 8 kbar) and amphibolite (611°C - 652° Cand 10.5 kbar) facies.
文摘A four-component reaction in the presence of Alum [KAl（SO4）2·12H2O] as an inexpensive and reusable catalyst using the ionic liquid as an effective green reaction media is reported.
文摘Synchronization of neurons plays an important role in vision, movement and memory. However, many neurological disorders such as epilepsies, Parkinson disease and essen- tial tremor are related to excessive synchronization of neurons. In the line of therapy, stimulations to these pathologically synchronized neurons should be capable of breaking synchrony. As the first step of designing an effective stimulation, we consider desynchro- nization problem of coupled limit-cycle oscillators ensemble. First, the desynchronization problem is redefined in a nonlinear output regulation framework. Then, we design an output regulator （stimulation） which forces limit-cycle oscillators to track exogenous sinusoidal references with different phases. The proposed stimulation is robust against variations of oscillators＇ frequencies. Mathematical analysis and simulation results reveal the efficiency of the proposed technique.
基金the National Natural Science Foundation of China(Grant Nos.11971142,11871202,61673169,11701176,11626101,11601485).YMC received the grant for this work.
文摘The purpose of this work is to find new soliton solutions of the complex Ginzburg–Landau equation(GLE)with Kerr law non-linearity.The considered equation is an imperative nonlinear partial differential equation(PDE)in the field of physics.The applications of complex GLE can be found in optics,plasma and other related fields.The modified extended tanh technique with Riccati equation is applied to solve the Complex GLE.The results are presented under a suitable choice for the values of parameters.Figures are shown using the three and two-dimensional plots to represent the shape of the solution in real,and imaginary parts in order to discuss the similarities and difference between them.The graphical representation of the results depicts the typical behavior of soliton solutions.The obtained soliton solutions are of different forms,such as,hyperbolic and trigonometric functions.The results presented in this paper are novel and reported first time in the literature.Simulation results establish the validity and applicability of the suggested technique for the complex GLE.The suggested method with symbolic computational software such as,Mathematica and Maple,is proven as an effective way to acquire the soliton solutions of nonlinear partial differential equations(PDEs)as well as complex PDEs.
文摘In this paper, we have studied electronic properties of a two-electron quantum dot using Tietz confining potential in the presence of an external magnetic field. In this regard, we have applied diagonalization procedure of Hamilonian matrix. We have calculated singlet-triplet ground state transitions as a function of the magnetic field. The obtained results show that the dot size of the Tietz potential has an important role in the ground state transition. The singlet-triplet transition of the ground state shifts towards lower magnetic field when the quantum size increases. Our results yield much less transitions than that of previous results [R.G. Nazmitdinov, N.S. Simonovic, and M.J. Rost, Phys.Rev. B 65(2002) 155307].
