The microstructural characteristics of P-25 TiO2 photocatalysts calcined at 600, 650,700, 750, 800, 900 and 1000℃ have been studied using XRD, TEM and BET. The photocatalytic activity of the samples were also examine...The microstructural characteristics of P-25 TiO2 photocatalysts calcined at 600, 650,700, 750, 800, 900 and 1000℃ have been studied using XRD, TEM and BET. The photocatalytic activity of the samples were also examined using the degradation of phenol as a model reaction.The results indicate that the calcination significantly affects both microstructural characteristics and photoactivity, and there is an apparent relationship between photocatalytic activity and centain mocrostructural characteristics.Over the range of calcination temperatures and durations studied, the sample calcined at 650℃ for 3 h revealed the highest photoreactivity, which can be ascribed to an improvement in crystallinity on calcination.The increase in the rutile content and grain size caused by the calcination at higher temperatures were observed to decrease the photocatalytic activities of the TiO2 samples.展开更多
The adsorption capacity for vapor-phase elemental mercury(Hg0) of residual carbon separated from fly ash was studied in an attempt for the control of elemental mercury emissions from combustion processes. At low mercu...The adsorption capacity for vapor-phase elemental mercury(Hg0) of residual carbon separated from fly ash was studied in an attempt for the control of elemental mercury emissions from combustion processes. At low mercury concentrations(<200 μg/m3), unburned carbon had higher adsorption capacity than commercial activated carbon. The adsorbality of unburned carbon was also found to be source dependent. Isotherms of FS carbon(separated from fly ash of a power plant of Shishi in Fujian Province) were similar to those classified as typeⅡ. Isotherms of XJ carbon(separated from fly ash of a power plant of Jingcheng in Shanxi Province) were more like those classified as type Ⅲ. Due to the relatively low production costs, these residual carbons would likely be considerably more cost-effective for the full-scale removal of mercury from combustion flue gases than other technology.展开更多
1.INTRODUCTIONMolecular topological property is an important property.A molecular topo-logical index is an invariant of molecular graph.Since the fist topologicalindex was put forward in 1947 by Wiener,just over 40 di...1.INTRODUCTIONMolecular topological property is an important property.A molecular topo-logical index is an invariant of molecular graph.Since the fist topologicalindex was put forward in 1947 by Wiener,just over 40 different topolo-gical indices have been documented in the literature to date.The theoryof molecular topological indices has become a more effective and simplermethod of studying the relationship between molecular structure and its phys-ical properties,chemical properties and biological activity.展开更多
Some criteria for the local activity theory in two-port cellular neural network cells with three local state variables are applied to a coupled Lorenz-cell model. The numerical simulation exhibited that emergence may ...Some criteria for the local activity theory in two-port cellular neural network cells with three local state variables are applied to a coupled Lorenz-cell model. The numerical simulation exhibited that emergence may exist if the selected cell parameters are nearby or on the edge of chaos domain. The local activity theory has provided a new tool of studying the complexity of high dimensional coupled nonlinear physical systems.展开更多
To understand the effect of alloy stoichiometry on the microstructural development and mechanical behavior of γ-TiAl- based materials, it is necessary to have a determination of the phase relationships for the TiAl ...To understand the effect of alloy stoichiometry on the microstructural development and mechanical behavior of γ-TiAl- based materials, it is necessary to have a determination of the phase relationships for the TiAl alloy system near the γ phase field. Cast structures and phases of Ti-(43-47)Al-8Nb-(1-2)Mn (at%) alloys have been studied by using scanning electron microscope and X-ray diffraction. Their solidification path and microstructure development during the solidification were analyzed. The experimental results show that the alloys with different Al contents form different macrostructures and microstructural morphologies. This indi- cates that the solidification paths are different with different Al contents. The alloy with 43Al forms equiaxed grain structure, and the solidification path is as follows: L —? L+β —? β —? α+β —> α+β cores —> O2+γ+B2 cores. Whereas the alloy with 47Al forms colum- nar grain structure, and the solidification path is as follows: L —> L+β —? α+β+L —? α+γ+β cores —> tXj+γ+BZ cores. The p phase is their primary solid phase and can be retained to ambient temperature. The alloy with 43Al solidifies completely into β phase. The peritectic reactions L+P —> α and L+α-? γ appear when the Al content increases to 47Al.展开更多
In order to reduce the operation time and improve the extraction efficiency, ultrasonic energy by means of ultrasonic bath was used to the modified Tessier sequential extraction for speciation analysis of heavy metals...In order to reduce the operation time and improve the extraction efficiency, ultrasonic energy by means of ultrasonic bath was used to the modified Tessier sequential extraction for speciation analysis of heavy metals in soil. Extractable contents of Cu, Fe, Mn, Ni, Pb and Zn were measured by atomic absorption spectroscopy(AAS). The merit of the ultrasonic extraction(UE) applied to the modified Tessier method is not only that the operation time for the first 4 fractions was reduced from ca.18 h to 8 h, comparing with conventional extraction(CE), but also the extraction efficiency was higher. The results for both of UE and CE were consistent. The extractable Cu, Ni and Zn in the sample No.1 were mainly associated with the third fraction(Fe-Mn oxides fraction), and fourth fraction(organic matter fraction) in the sample No.2. The extractable Fe and Mn were all mainly associated with the third fraction, and Pb the fourth fraction in both of the samples. The effects of concentration of hydroxylamine chloride on the capability for the extraction of studied metals were also studied.展开更多
The purpose of this paper is to study complete space-like submanifolds with parallel mean curvature vector and flat normal bundle in a locally symmetric semi-defnite space satisfying some curvature conditions. We firs...The purpose of this paper is to study complete space-like submanifolds with parallel mean curvature vector and flat normal bundle in a locally symmetric semi-defnite space satisfying some curvature conditions. We first give an optimal estimate of the Laplacian of the squared norm of the second fundamental form for such submanifold. Furthermore, the totally umbilical submanifolds are characterized.展开更多
Silicon fines, boron acid solid powders and microfine SiO 2 as sintering agents were incorporated into Al 2O 3-SiC-C ramming mix in order to investigated their effects on the microstructure, mechanical properties a...Silicon fines, boron acid solid powders and microfine SiO 2 as sintering agents were incorporated into Al 2O 3-SiC-C ramming mix in order to investigated their effects on the microstructure, mechanical properties and sintering behavior of the ramming mix. Results show that all the three agents could improved both densification and mehanical properties markedly, compared to that of non-agent specimens and the effect of the composite of boron acid solid powders and microfine SiO 2 is the best. The oxidation resistance increased with the addition of agents, which is supported by densification. Microstructures showed that agent powders could fill pores or produce liquid phases at high temperature, therefore, improve the sintering of the ramming mix.展开更多
This paper describes an application of a reusable mobile agent system in network management. A mobile agent reusable system is constructed to realize a new method in forming mobile agent systems. By using this method,...This paper describes an application of a reusable mobile agent system in network management. A mobile agent reusable system is constructed to realize a new method in forming mobile agent systems. By using this method, an agent can change its route dynamically without making any change to its specific behavior. By classifying mobile agents into two categories, the task agent can be reusable in different networks. In this way, a mobile agent system can easily carry out network management tasks.展开更多
Let M be a compact minimal hypersurface of sphere Sn+1(1). Let M be H(r)-torus of sphere Sn+1(1).Assume they have the same constant mean curvature H, the result in [1] is that if Spec0 (M, g) =Spec0(M, g),then for 3 ...Let M be a compact minimal hypersurface of sphere Sn+1(1). Let M be H(r)-torus of sphere Sn+1(1).Assume they have the same constant mean curvature H, the result in [1] is that if Spec0 (M, g) =Spec0(M, g),then for 3 ≤ n ≤ 6,r2 ≤n-1/n or n > 6,r2 ≥ n-1/n, then M is isometric to M. We improvedthe result and prove that: if Spec0(M, g) =Spec0(M, g), then M is isometric to M. Generally, if Specp(M,g) =Specp(M, g), here p is fixed and satisfies that n(n - 1) ≠ 6p(n - p), then M is isometric to M.展开更多
A new algorithm for mining quantitative association rules with standard SQL is presented. The association rules are evaluated with the sufficiency gene LS of subjectivity Bayes reasoning. This algorithm is proved to b...A new algorithm for mining quantitative association rules with standard SQL is presented. The association rules are evaluated with the sufficiency gene LS of subjectivity Bayes reasoning. This algorithm is proved to be quick and effective with its application in Lujiang insects and pests database.展开更多
Boehmite sol is synthesized via sol-gel process using Al 2(SO 4) 3·18H 2O and (CH 2) 6N 4 as starting materials, then adding silica sol into boehmite sol to prepare mullite precursor gels. XRD studies are ...Boehmite sol is synthesized via sol-gel process using Al 2(SO 4) 3·18H 2O and (CH 2) 6N 4 as starting materials, then adding silica sol into boehmite sol to prepare mullite precursor gels. XRD studies are performed to characterize the gels. It is found that the gel can be transformed into mullite when calcined at 1100℃ and completed at 1300℃. Corundum-mullite firebricks with different additions of the mullite precursor gel are made by mixing, semi-dry pressing and then sintering at 1520℃. Apparent porosity, bulk density, flexural strength and thermal shock resistance are measured. Results show that the mullite gel can improve densification and strength of corundum-mullite firebricks, especially enhance the thermal shock resistance. SEM micrographs show that the gel added can be formed into needlelike and elongated mullite in the matrix, whose micromorphology can enhance the strength and thermal shock resistance of the samples.展开更多
A two-dimensional model was applied to simulate the liquid core reduction (LCR) technology of bloom CC using ANSYS software. The deformation characteristics of bloom under different liquid fraction and reducing amount...A two-dimensional model was applied to simulate the liquid core reduction (LCR) technology of bloom CC using ANSYS software. The deformation characteristics of bloom under different liquid fraction and reducing amount are obtained. The results indicate that the main deformation condition of bloom shell is compressive strain, mainly undertaken by the liquid core, which increases with the enhancement of reducing amount. Solidified shell takes minor deformation. The longitudinal section of bloom appears sunken and the narrow side bulges, which grow serious when the liquid fraction increases.展开更多
This paper presents a modified structure of a neural network with tunable activation function and provides a new learning algorithm for the neural network training. Simulation results of XOR problem, Feigenbaum functi...This paper presents a modified structure of a neural network with tunable activation function and provides a new learning algorithm for the neural network training. Simulation results of XOR problem, Feigenbaum function, and Henon map show that the new algorithm has better performance than BP (back propagation) algorithm in terms of shorter convergence time and higher convergence accuracy. Further modifications of the structure of the neural network with the faster learning algorithm demonstrate simpler structure with even faster convergence speed and better convergence accuracy.展开更多
A series of 1,8,15,22-tetra(2,4-ditertbutylphen- oxy) phthalocyanines [a-(oAr)4PcM, M1=(H)2, M2=Pd, M3= Cu, M4=Zn, M5=Pb] were synthesized in this study. Each compound was bromized in two kinds of solvent. One is the ...A series of 1,8,15,22-tetra(2,4-ditertbutylphen- oxy) phthalocyanines [a-(oAr)4PcM, M1=(H)2, M2=Pd, M3= Cu, M4=Zn, M5=Pb] were synthesized in this study. Each compound was bromized in two kinds of solvent. One is the solvent mixture of 1,1,2-trichloroethane and water, the other is 1,1,2-trichloroethane alone. The effects of solvent, bromine excess added and reaction duration on the bromization reac-tion were studied. The shift of maximum absorbance wave-length both in solution and in solid thin film was investigated comparatively, discovering that both were bathochromism but the former was more. TG data showed that the tem-perature of thermal decomposition decreased continuously with the increase of numbers of bromine. Finally, the frag-ments produced during the bromization of (OAr)4PcPb in 1,1,2- trichloroethane were characterized by GC/MS. Based on the electronic structure, the possible mechanism of de-composition of these compounds was presented and dis-cussed.展开更多
This dissertation deals with the internal waves generated by a submergedmoving body in stratified fluids by combining theoretical and experimental methods. Our purpose isto provide some scientific evidences for non-ac...This dissertation deals with the internal waves generated by a submergedmoving body in stratified fluids by combining theoretical and experimental methods. Our purpose isto provide some scientific evidences for non-acoustic detection of underwater moving bodies based onthe principles of dynamics of the internal waves. An approach to velocity potentials obtained bysuperposing Green''s functions of sources and sinks was proposed for Kelvin waves at the free surfaceor interface in a two-layer fluid. The effects of interacting surface- and internal-wave modesinduced by a dipole on the surface divergence field were investigated. A new theoretical modelformulating the interaction of a two-dimensional submerged moving body with the conjugate flow in athree-layer fluid was established. An exact solution satisfying the two-dimensional Benjamin-Onoequation was obtained and the vertically propagating properties of the weakly nonlinear long waveswere studied by means of the ray theory and WKB method. The above theoretical results arequalitatively consistent with those obtained in the experiments conducted by the author.展开更多
The magnetic phase transition and magneto- caloric effect of Gd5Si1.85Ge2.15 alloy are studied. The alloy was prepared from distilled commercial gadolinium. The major impurities (in wt.%) in the distilled commercial G...The magnetic phase transition and magneto- caloric effect of Gd5Si1.85Ge2.15 alloy are studied. The alloy was prepared from distilled commercial gadolinium. The major impurities (in wt.%) in the distilled commercial Gd are 0.016 O, 0.0054 C, and 0.0016 N. The impurities are higher than those in the high pure Gd but lower than those in commercial Gd. The results of X-ray diffraction and magnetic susceptibility show that there exists the first-order magnetic phase transition in the Gd5Si1.85Ge2.15 alloy at 253 K. The maximum of magnetic entropy change Smax is 12.5 J/kg·K near the temperature of magnetic phase transition in the alloy.展开更多
In this paper, the Extended Self Similarity (ESS) was used to study thescaling exponent ξ(q) of temperature data in the Reyleigh-Benard convection and its variation withexperimental measuring locations. The results s...In this paper, the Extended Self Similarity (ESS) was used to study thescaling exponent ξ(q) of temperature data in the Reyleigh-Benard convection and its variation withexperimental measuring locations. The results show that ξ(q) varies with locations and agrees wellwith experimental data. And then the wavelet transformation is used to extract the coherentstructure, by means of the definition of a called non-coherent signal. we can understand theinfluence of coherent structure on ξ(q) and the relations between large scale vortex motions andsmall ones.展开更多
文摘The microstructural characteristics of P-25 TiO2 photocatalysts calcined at 600, 650,700, 750, 800, 900 and 1000℃ have been studied using XRD, TEM and BET. The photocatalytic activity of the samples were also examined using the degradation of phenol as a model reaction.The results indicate that the calcination significantly affects both microstructural characteristics and photoactivity, and there is an apparent relationship between photocatalytic activity and centain mocrostructural characteristics.Over the range of calcination temperatures and durations studied, the sample calcined at 650℃ for 3 h revealed the highest photoreactivity, which can be ascribed to an improvement in crystallinity on calcination.The increase in the rutile content and grain size caused by the calcination at higher temperatures were observed to decrease the photocatalytic activities of the TiO2 samples.
基金The National Natural Science Foundation of China(No. 50306010) and the National Basic Research Program(973) of China(No. G1999022200)
文摘The adsorption capacity for vapor-phase elemental mercury(Hg0) of residual carbon separated from fly ash was studied in an attempt for the control of elemental mercury emissions from combustion processes. At low mercury concentrations(<200 μg/m3), unburned carbon had higher adsorption capacity than commercial activated carbon. The adsorbality of unburned carbon was also found to be source dependent. Isotherms of FS carbon(separated from fly ash of a power plant of Shishi in Fujian Province) were similar to those classified as typeⅡ. Isotherms of XJ carbon(separated from fly ash of a power plant of Jingcheng in Shanxi Province) were more like those classified as type Ⅲ. Due to the relatively low production costs, these residual carbons would likely be considerably more cost-effective for the full-scale removal of mercury from combustion flue gases than other technology.
文摘1.INTRODUCTIONMolecular topological property is an important property.A molecular topo-logical index is an invariant of molecular graph.Since the fist topologicalindex was put forward in 1947 by Wiener,just over 40 different topolo-gical indices have been documented in the literature to date.The theoryof molecular topological indices has become a more effective and simplermethod of studying the relationship between molecular structure and its phys-ical properties,chemical properties and biological activity.
文摘Some criteria for the local activity theory in two-port cellular neural network cells with three local state variables are applied to a coupled Lorenz-cell model. The numerical simulation exhibited that emergence may exist if the selected cell parameters are nearby or on the edge of chaos domain. The local activity theory has provided a new tool of studying the complexity of high dimensional coupled nonlinear physical systems.
基金This research was sponsored by the State Key Project for Fundamental Research Developing Plan (No.G2000067206-2) and theNational Natural Science Foundation of China (No. 50274005).
文摘To understand the effect of alloy stoichiometry on the microstructural development and mechanical behavior of γ-TiAl- based materials, it is necessary to have a determination of the phase relationships for the TiAl alloy system near the γ phase field. Cast structures and phases of Ti-(43-47)Al-8Nb-(1-2)Mn (at%) alloys have been studied by using scanning electron microscope and X-ray diffraction. Their solidification path and microstructure development during the solidification were analyzed. The experimental results show that the alloys with different Al contents form different macrostructures and microstructural morphologies. This indi- cates that the solidification paths are different with different Al contents. The alloy with 43Al forms equiaxed grain structure, and the solidification path is as follows: L —? L+β —? β —? α+β —> α+β cores —> O2+γ+B2 cores. Whereas the alloy with 47Al forms colum- nar grain structure, and the solidification path is as follows: L —> L+β —? α+β+L —? α+γ+β cores —> tXj+γ+BZ cores. The p phase is their primary solid phase and can be retained to ambient temperature. The alloy with 43Al solidifies completely into β phase. The peritectic reactions L+P —> α and L+α-? γ appear when the Al content increases to 47Al.
文摘In order to reduce the operation time and improve the extraction efficiency, ultrasonic energy by means of ultrasonic bath was used to the modified Tessier sequential extraction for speciation analysis of heavy metals in soil. Extractable contents of Cu, Fe, Mn, Ni, Pb and Zn were measured by atomic absorption spectroscopy(AAS). The merit of the ultrasonic extraction(UE) applied to the modified Tessier method is not only that the operation time for the first 4 fractions was reduced from ca.18 h to 8 h, comparing with conventional extraction(CE), but also the extraction efficiency was higher. The results for both of UE and CE were consistent. The extractable Cu, Ni and Zn in the sample No.1 were mainly associated with the third fraction(Fe-Mn oxides fraction), and fourth fraction(organic matter fraction) in the sample No.2. The extractable Fe and Mn were all mainly associated with the third fraction, and Pb the fourth fraction in both of the samples. The effects of concentration of hydroxylamine chloride on the capability for the extraction of studied metals were also studied.
文摘The purpose of this paper is to study complete space-like submanifolds with parallel mean curvature vector and flat normal bundle in a locally symmetric semi-defnite space satisfying some curvature conditions. We first give an optimal estimate of the Laplacian of the squared norm of the second fundamental form for such submanifold. Furthermore, the totally umbilical submanifolds are characterized.
文摘Silicon fines, boron acid solid powders and microfine SiO 2 as sintering agents were incorporated into Al 2O 3-SiC-C ramming mix in order to investigated their effects on the microstructure, mechanical properties and sintering behavior of the ramming mix. Results show that all the three agents could improved both densification and mehanical properties markedly, compared to that of non-agent specimens and the effect of the composite of boron acid solid powders and microfine SiO 2 is the best. The oxidation resistance increased with the addition of agents, which is supported by densification. Microstructures showed that agent powders could fill pores or produce liquid phases at high temperature, therefore, improve the sintering of the ramming mix.
文摘This paper describes an application of a reusable mobile agent system in network management. A mobile agent reusable system is constructed to realize a new method in forming mobile agent systems. By using this method, an agent can change its route dynamically without making any change to its specific behavior. By classifying mobile agents into two categories, the task agent can be reusable in different networks. In this way, a mobile agent system can easily carry out network management tasks.
基金Supported by National Natural Science Foundation of China (10371047)
文摘Let M be a compact minimal hypersurface of sphere Sn+1(1). Let M be H(r)-torus of sphere Sn+1(1).Assume they have the same constant mean curvature H, the result in [1] is that if Spec0 (M, g) =Spec0(M, g),then for 3 ≤ n ≤ 6,r2 ≤n-1/n or n > 6,r2 ≥ n-1/n, then M is isometric to M. We improvedthe result and prove that: if Spec0(M, g) =Spec0(M, g), then M is isometric to M. Generally, if Specp(M,g) =Specp(M, g), here p is fixed and satisfies that n(n - 1) ≠ 6p(n - p), then M is isometric to M.
文摘A new algorithm for mining quantitative association rules with standard SQL is presented. The association rules are evaluated with the sufficiency gene LS of subjectivity Bayes reasoning. This algorithm is proved to be quick and effective with its application in Lujiang insects and pests database.
文摘Boehmite sol is synthesized via sol-gel process using Al 2(SO 4) 3·18H 2O and (CH 2) 6N 4 as starting materials, then adding silica sol into boehmite sol to prepare mullite precursor gels. XRD studies are performed to characterize the gels. It is found that the gel can be transformed into mullite when calcined at 1100℃ and completed at 1300℃. Corundum-mullite firebricks with different additions of the mullite precursor gel are made by mixing, semi-dry pressing and then sintering at 1520℃. Apparent porosity, bulk density, flexural strength and thermal shock resistance are measured. Results show that the mullite gel can improve densification and strength of corundum-mullite firebricks, especially enhance the thermal shock resistance. SEM micrographs show that the gel added can be formed into needlelike and elongated mullite in the matrix, whose micromorphology can enhance the strength and thermal shock resistance of the samples.
文摘A two-dimensional model was applied to simulate the liquid core reduction (LCR) technology of bloom CC using ANSYS software. The deformation characteristics of bloom under different liquid fraction and reducing amount are obtained. The results indicate that the main deformation condition of bloom shell is compressive strain, mainly undertaken by the liquid core, which increases with the enhancement of reducing amount. Solidified shell takes minor deformation. The longitudinal section of bloom appears sunken and the narrow side bulges, which grow serious when the liquid fraction increases.
文摘This paper presents a modified structure of a neural network with tunable activation function and provides a new learning algorithm for the neural network training. Simulation results of XOR problem, Feigenbaum function, and Henon map show that the new algorithm has better performance than BP (back propagation) algorithm in terms of shorter convergence time and higher convergence accuracy. Further modifications of the structure of the neural network with the faster learning algorithm demonstrate simpler structure with even faster convergence speed and better convergence accuracy.
文摘A series of 1,8,15,22-tetra(2,4-ditertbutylphen- oxy) phthalocyanines [a-(oAr)4PcM, M1=(H)2, M2=Pd, M3= Cu, M4=Zn, M5=Pb] were synthesized in this study. Each compound was bromized in two kinds of solvent. One is the solvent mixture of 1,1,2-trichloroethane and water, the other is 1,1,2-trichloroethane alone. The effects of solvent, bromine excess added and reaction duration on the bromization reac-tion were studied. The shift of maximum absorbance wave-length both in solution and in solid thin film was investigated comparatively, discovering that both were bathochromism but the former was more. TG data showed that the tem-perature of thermal decomposition decreased continuously with the increase of numbers of bromine. Finally, the frag-ments produced during the bromization of (OAr)4PcPb in 1,1,2- trichloroethane were characterized by GC/MS. Based on the electronic structure, the possible mechanism of de-composition of these compounds was presented and dis-cussed.
文摘This dissertation deals with the internal waves generated by a submergedmoving body in stratified fluids by combining theoretical and experimental methods. Our purpose isto provide some scientific evidences for non-acoustic detection of underwater moving bodies based onthe principles of dynamics of the internal waves. An approach to velocity potentials obtained bysuperposing Green''s functions of sources and sinks was proposed for Kelvin waves at the free surfaceor interface in a two-layer fluid. The effects of interacting surface- and internal-wave modesinduced by a dipole on the surface divergence field were investigated. A new theoretical modelformulating the interaction of a two-dimensional submerged moving body with the conjugate flow in athree-layer fluid was established. An exact solution satisfying the two-dimensional Benjamin-Onoequation was obtained and the vertically propagating properties of the weakly nonlinear long waveswere studied by means of the ray theory and WKB method. The above theoretical results arequalitatively consistent with those obtained in the experiments conducted by the author.
基金supported by the National Natural Science Foundation of China(Grant No.50071006)the“863”Program(Grant No.2002AA324101).
文摘The magnetic phase transition and magneto- caloric effect of Gd5Si1.85Ge2.15 alloy are studied. The alloy was prepared from distilled commercial gadolinium. The major impurities (in wt.%) in the distilled commercial Gd are 0.016 O, 0.0054 C, and 0.0016 N. The impurities are higher than those in the high pure Gd but lower than those in commercial Gd. The results of X-ray diffraction and magnetic susceptibility show that there exists the first-order magnetic phase transition in the Gd5Si1.85Ge2.15 alloy at 253 K. The maximum of magnetic entropy change Smax is 12.5 J/kg·K near the temperature of magnetic phase transition in the alloy.
文摘In this paper, the Extended Self Similarity (ESS) was used to study thescaling exponent ξ(q) of temperature data in the Reyleigh-Benard convection and its variation withexperimental measuring locations. The results show that ξ(q) varies with locations and agrees wellwith experimental data. And then the wavelet transformation is used to extract the coherentstructure, by means of the definition of a called non-coherent signal. we can understand theinfluence of coherent structure on ξ(q) and the relations between large scale vortex motions andsmall ones.
