The Pomeron-nucleon coupling vertex is theoretically derived from the fundamental theory of strong interaction QCD. The empirical vertex βγ^μF1 （t） used commonly in diffractive processes with a coupling strength ...The Pomeron-nucleon coupling vertex is theoretically derived from the fundamental theory of strong interaction QCD. The empirical vertex βγ^μF1 （t） used commonly in diffractive processes with a coupling strength β = 6.0 GeV^-1 is initially obtained from QCD theoretically. Our study not only reproduces the Pomeron-nucleon coupling from QCD but also clearly shows the gluonlc origin and glueball nature of Pomeron, which is a longstanding puzzle. From this investigation, we claim that Pomeron can be regarded as a Reggeized tensor glueball ζ（2230） with quantum numbers of I^GJ^PC = 0＋2＋＋. Since the tensor glueball ζ（2230） lies on the Pomeron trajectory αp（t = Mζ^2） = 2, the longstanding puzzle that no physical particle lies on the Pomeron trajectory, αp（t） = 1.08 ＋ 0.20 GeV^-2 .t, seems to be solved.展开更多
The synthesis of high purity intermetallic FeAI nanoparticles using the flow-levitation （FL） method was reported. Iron and aluminium droplets were levitated stably at about 2 230℃. The morphology, clystal structure...The synthesis of high purity intermetallic FeAI nanoparticles using the flow-levitation （FL） method was reported. Iron and aluminium droplets were levitated stably at about 2 230℃. The morphology, clystal structure and chemical composition of FeAI nanoparticles were investigated by transmission electron microscopy （TEM）, high-resolution TEM, X-ray diffraction and energy dispersive spectrometry. The results show that the average particle size of these nanoparticles is about 34.5 nm. Measurements of the d-spacing from X-ray diffraction and electron diffraction studies confirm that the intermetallic nanoparticles have the same crystal structure （B2） as the bulk FeA1. A thin oxidation coating is formed around the particles when being exposed to air. Based on the XPS measurements, the surface coating of the FeAI nanoparticles is composed of Fe2O3 and FeAl2O4. Besides, hysteresis curve reveals that saturation magnetization （Ms） of FeA1 is 1.66 A/m2, and the coercivity is about 1.214×10^3 A/re.展开更多
Based on Pomeron exchange model, elastic production of vector meson in electro-proton interaction is investigated with both linear and non-linear Pomeron trajectory. A numerical calculation for J/psi production is per...Based on Pomeron exchange model, elastic production of vector meson in electro-proton interaction is investigated with both linear and non-linear Pomeron trajectory. A numerical calculation for J/psi production is performed. The effect of the energy scale so and photon virtuality Q(2) on differential cross section are also predicted. A good agreement with experimental data is obtained. Our conclusions are that the Pomeron exchange model is a successful description of J/psi electro-production, the dependence of the differential cross sections on Q2 is negligible, the linear trajectory is a good approximation to non-linearity of the Pomeron trajectory, and the value of the energy scale parameter so is dependent on the momentum transfer, namely its effect is moderate at low momentum transfer but it causes no difference at high momentum transfer vertical bar t vertical bar >= 1.25 GeV2.展开更多
Based on Pomeron exchange model, J/ψ and φ production in electro-proton interaction are investigated with both linear and non-linear Pomeron trajectory. The experimental differential cross sections measured as a fun...Based on Pomeron exchange model, J/ψ and φ production in electro-proton interaction are investigated with both linear and non-linear Pomeron trajectory. The experimental differential cross sections measured as a function of the kinematic variable Q^2,W and t are reproduced successfully in the model. Our conclusions are that the Pomeron exchange model is a successful description of J/ψ and φ electro-productions on the proton, and that the linear trajectory is a good approximation to non-linearity of the Pomeron trajectory.展开更多
Based on the assumption that the Pomeron is a sum of Regge multipoles, each of which corresponds to a finite gluon ladder, we suggest a way to search the Odderon by studying the diffractive processes of ^-pp and pp el...Based on the assumption that the Pomeron is a sum of Regge multipoles, each of which corresponds to a finite gluon ladder, we suggest a way to search the Odderon by studying the diffractive processes of ^-pp and pp elastic scattering. From our theoretical calculations and fits to the corresponding experimental data at high energies and all available momentum transfer, we find that the Odderon plays a significant role in the description of differential cross section dσ/ dt in the whole experimental domain. Accordingly, we can claim that the ^-pp and pp diffractive processes at high energies s and moderate momentum transfer t could be a good tool to search for Odderon and to test QCD since the processes are purely non-perturbative QCD phenomena. Therefore, the experimental measurements are urgently demanded.展开更多
A highly intense green-emitting phosphor of Eu2＋-doped Sr4Al14O25 （SAE：Eu2＋） was synthesized by a solid state reaction. In this study, XRD, PL/PLE, QE, thermal stability and LED package tests are systematically c...A highly intense green-emitting phosphor of Eu2＋-doped Sr4Al14O25 （SAE：Eu2＋） was synthesized by a solid state reaction. In this study, XRD, PL/PLE, QE, thermal stability and LED package tests are systematically carried out and investigated. The optimized-composition of （Sro 92Eu0.08）4Al14025 exhibited a green emission peak at 497 nm under excitation wavelength of 400 nm, giving the chromaticity coordinates of （0.14, 0.35） with excellent quantum efficiency （98%） compared to those of other green-commodities, such as Ba2SiO4：Eu2＋ （90%） and BaMgAl10O17：EU2＋, Mn2＋ （92%）. The results demonstrated that SAE：Eu2＋ could be a potential candidate as the NUV-pumping phosphor for applications in light-emitting diodes （LEDs）.展开更多
Several bacterial strains of Actinomycetes belonging to Streptomyces and Arthrobacter genera for the first time were used to study the biotechnology of synthesis of gold and silver nanoparticles. The experimental cond...Several bacterial strains of Actinomycetes belonging to Streptomyces and Arthrobacter genera for the first time were used to study the biotechnology of synthesis of gold and silver nanoparticles. The experimental conditions of gold and silver nanoparticles production by the cells of studied strains in aqueous chloroauric acid （HAuCIq） and in silver nitrate （AgNO3） solutions, respectively, were determined. Concentration and time-dependences of nanoparticle formation were investigated. The complex of optical and analytical methods was used for testing the gold and silver nanoparticles in the bacterial biomass. The TEM （Transmission Electron Microscopy） and XRD （X-ray Diffraction） data in all cases demonstrated the presence of crystals with fcc （face centered cubic） structure. The results obtained show that the Actinomycetes are capable of producing gold and silver nanoparticles of spherical shape extracellularly when exposed to suitable compounds. The particle size distribution shows that the sizes of nanoparticles are in the range of 5 nm to 80 nm. The biomass obtained may be used for industrial as well as medical and pharmaceutical purposes.展开更多
We examine the effect of the electron exchange-correlation on weak and arbitrary amplitude quantum dust ion-acoustic(QDIA) solitons.The reduced quantum hydrodynamic(QHD) model is used.Carrying out a fully nonlinear an...We examine the effect of the electron exchange-correlation on weak and arbitrary amplitude quantum dust ion-acoustic(QDIA) solitons.The reduced quantum hydrodynamic(QHD) model is used.Carrying out a fully nonlinear analysis,it is found that the effect of the exchange-correlation on the main quantities for solitary-wave propagation can be quite important.In particular,it may be noted that the arbitrary amplitude QDIA soliton experiences a spreading as the phenomenon of exchange-correlation becomes effective.Furthermore,our results show that the exchange-correlation effects inhibit the formation of the flat-bottomed solitons and do not favor their emergence.It turns out that exchangecorrelation and quantum diffraction may act concurrently to set up the conditions for the existence of the QDIA solitary waves.Our results complement and provide new insight into our previously published work on this problem.展开更多
Zinc nanoplates were grown using thermal evaporation without catalyst or template involved.Tunneling electron microscopy and selected area electron diffraction analyses showed that the plates were single crystals with...Zinc nanoplates were grown using thermal evaporation without catalyst or template involved.Tunneling electron microscopy and selected area electron diffraction analyses showed that the plates were single crystals with either {0001} or {11 20} as basal surfaces.The morphological characteristics were explained in terms of the intrinsic growth anisotropy of zinc,the surface energy of the nano-crystals,the size of the critical nucleus and the migration of the adatoms.Our results suggested a promising low-cost route for synthesis of pure zinc nanoplates which could be used as precursor for further preparing core-shell nanoplate structures.展开更多
FesoMn15-xCoxNi35 （x=0, 1, 3, 5, 7） alloys were prepared by arc melting under purified argon atmosphere. The ingots were homogenized at 930℃ for 90 h followed by water quenching. The crystal structure, magnetic pro...FesoMn15-xCoxNi35 （x=0, 1, 3, 5, 7） alloys were prepared by arc melting under purified argon atmosphere. The ingots were homogenized at 930℃ for 90 h followed by water quenching. The crystal structure, magnetic properties and magnetocaloric effects of the alloys were studied by X-ray diffraction （XRD） and MPMS-7-type SQUID. The results show that all samples still maintained a single γ-（Fe, Ni）-type phase structure. With the increase of the content of Co, the Curie temperatures of these alloys increased and exhibited a second-order magnetic transition from ferromagnetic （FM） to paramagnetic （PM） state near Curie temperature. The maximum magnetic entropy change and the relative cooling power of Fe50Mn10CosNi35 alloy was 2.55 J/kg.K and 181 J/kg, respectively, for an external field change of 5 T. Compared with rare earth metal Gd, FesoMnls-xCoxNi35 series of alloys have obvious advantage in resource price; their Curie temperatures can be tuned to near room temperature, maintain a relatively large magnetic entropy change at the same time and they are a type of potential magnetic refrigeration materials near room temperature.展开更多
文摘The Pomeron-nucleon coupling vertex is theoretically derived from the fundamental theory of strong interaction QCD. The empirical vertex βγ^μF1 （t） used commonly in diffractive processes with a coupling strength β = 6.0 GeV^-1 is initially obtained from QCD theoretically. Our study not only reproduces the Pomeron-nucleon coupling from QCD but also clearly shows the gluonlc origin and glueball nature of Pomeron, which is a longstanding puzzle. From this investigation, we claim that Pomeron can be regarded as a Reggeized tensor glueball ζ（2230） with quantum numbers of I^GJ^PC = 0＋2＋＋. Since the tensor glueball ζ（2230） lies on the Pomeron trajectory αp（t = Mζ^2） = 2, the longstanding puzzle that no physical particle lies on the Pomeron trajectory, αp（t） = 1.08 ＋ 0.20 GeV^-2 .t, seems to be solved.
基金Project(10804101) supported by the National Natural Science Foundation of China
文摘The synthesis of high purity intermetallic FeAI nanoparticles using the flow-levitation （FL） method was reported. Iron and aluminium droplets were levitated stably at about 2 230℃. The morphology, clystal structure and chemical composition of FeAI nanoparticles were investigated by transmission electron microscopy （TEM）, high-resolution TEM, X-ray diffraction and energy dispersive spectrometry. The results show that the average particle size of these nanoparticles is about 34.5 nm. Measurements of the d-spacing from X-ray diffraction and electron diffraction studies confirm that the intermetallic nanoparticles have the same crystal structure （B2） as the bulk FeA1. A thin oxidation coating is formed around the particles when being exposed to air. Based on the XPS measurements, the surface coating of the FeAI nanoparticles is composed of Fe2O3 and FeAl2O4. Besides, hysteresis curve reveals that saturation magnetization （Ms） of FeA1 is 1.66 A/m2, and the coercivity is about 1.214×10^3 A/re.
文摘Based on Pomeron exchange model, elastic production of vector meson in electro-proton interaction is investigated with both linear and non-linear Pomeron trajectory. A numerical calculation for J/psi production is performed. The effect of the energy scale so and photon virtuality Q(2) on differential cross section are also predicted. A good agreement with experimental data is obtained. Our conclusions are that the Pomeron exchange model is a successful description of J/psi electro-production, the dependence of the differential cross sections on Q2 is negligible, the linear trajectory is a good approximation to non-linearity of the Pomeron trajectory, and the value of the energy scale parameter so is dependent on the momentum transfer, namely its effect is moderate at low momentum transfer but it causes no difference at high momentum transfer vertical bar t vertical bar >= 1.25 GeV2.
基金The project supported in part by National Natural Science Foundation of China under Grant Nos. 10565001, 10647002 and the Natural Science Foundation of Guangxi under Grant No. 0481030, 0542042, and 0575020, Guangxi University under Grant No. X051001, and Guangxi University of Technology under Grant No. 05006
文摘Based on Pomeron exchange model, J/ψ and φ production in electro-proton interaction are investigated with both linear and non-linear Pomeron trajectory. The experimental differential cross sections measured as a function of the kinematic variable Q^2,W and t are reproduced successfully in the model. Our conclusions are that the Pomeron exchange model is a successful description of J/ψ and φ electro-productions on the proton, and that the linear trajectory is a good approximation to non-linearity of the Pomeron trajectory.
基金The project supported in part by National Natural Science Foundation of China under Grant No. 10565001, the Natural Science Foundation of Guangxi under Grant Nos. 0542042, 0481030, and 0575020, and the Financial Support of Guangxi University of Technology under Grant No. 05006
文摘Based on the assumption that the Pomeron is a sum of Regge multipoles, each of which corresponds to a finite gluon ladder, we suggest a way to search the Odderon by studying the diffractive processes of ^-pp and pp elastic scattering. From our theoretical calculations and fits to the corresponding experimental data at high energies and all available momentum transfer, we find that the Odderon plays a significant role in the description of differential cross section dσ/ dt in the whole experimental domain. Accordingly, we can claim that the ^-pp and pp diffractive processes at high energies s and moderate momentum transfer t could be a good tool to search for Odderon and to test QCD since the processes are purely non-perturbative QCD phenomena. Therefore, the experimental measurements are urgently demanded.
文摘A highly intense green-emitting phosphor of Eu2＋-doped Sr4Al14O25 （SAE：Eu2＋） was synthesized by a solid state reaction. In this study, XRD, PL/PLE, QE, thermal stability and LED package tests are systematically carried out and investigated. The optimized-composition of （Sro 92Eu0.08）4Al14025 exhibited a green emission peak at 497 nm under excitation wavelength of 400 nm, giving the chromaticity coordinates of （0.14, 0.35） with excellent quantum efficiency （98%） compared to those of other green-commodities, such as Ba2SiO4：Eu2＋ （90%） and BaMgAl10O17：EU2＋, Mn2＋ （92%）. The results demonstrated that SAE：Eu2＋ could be a potential candidate as the NUV-pumping phosphor for applications in light-emitting diodes （LEDs）.
文摘Several bacterial strains of Actinomycetes belonging to Streptomyces and Arthrobacter genera for the first time were used to study the biotechnology of synthesis of gold and silver nanoparticles. The experimental conditions of gold and silver nanoparticles production by the cells of studied strains in aqueous chloroauric acid （HAuCIq） and in silver nitrate （AgNO3） solutions, respectively, were determined. Concentration and time-dependences of nanoparticle formation were investigated. The complex of optical and analytical methods was used for testing the gold and silver nanoparticles in the bacterial biomass. The TEM （Transmission Electron Microscopy） and XRD （X-ray Diffraction） data in all cases demonstrated the presence of crystals with fcc （face centered cubic） structure. The results obtained show that the Actinomycetes are capable of producing gold and silver nanoparticles of spherical shape extracellularly when exposed to suitable compounds. The particle size distribution shows that the sizes of nanoparticles are in the range of 5 nm to 80 nm. The biomass obtained may be used for industrial as well as medical and pharmaceutical purposes.
文摘We examine the effect of the electron exchange-correlation on weak and arbitrary amplitude quantum dust ion-acoustic(QDIA) solitons.The reduced quantum hydrodynamic(QHD) model is used.Carrying out a fully nonlinear analysis,it is found that the effect of the exchange-correlation on the main quantities for solitary-wave propagation can be quite important.In particular,it may be noted that the arbitrary amplitude QDIA soliton experiences a spreading as the phenomenon of exchange-correlation becomes effective.Furthermore,our results show that the exchange-correlation effects inhibit the formation of the flat-bottomed solitons and do not favor their emergence.It turns out that exchangecorrelation and quantum diffraction may act concurrently to set up the conditions for the existence of the QDIA solitary waves.Our results complement and provide new insight into our previously published work on this problem.
基金supported by the National Science Foundation of China(Grant Nos. 10875144 and 10979057)the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No.200800271045)
文摘Zinc nanoplates were grown using thermal evaporation without catalyst or template involved.Tunneling electron microscopy and selected area electron diffraction analyses showed that the plates were single crystals with either {0001} or {11 20} as basal surfaces.The morphological characteristics were explained in terms of the intrinsic growth anisotropy of zinc,the surface energy of the nano-crystals,the size of the critical nucleus and the migration of the adatoms.Our results suggested a promising low-cost route for synthesis of pure zinc nanoplates which could be used as precursor for further preparing core-shell nanoplate structures.
基金supported by the National Natural Science Foundation of China(Grant Nos.11032011 and 10872202)the Guangdong Provincial Science and Technology Program(Grant No.2010B050300008)+2 种基金the Guangzhou Municipal Science and Technology Program(Grant No.12F582080022)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry(Grant No.x2clB7120290)the Fundamental Research Funds for the Central Universities(Grant Nos.2012ZZ0013 and 2014ZZ0005)
文摘FesoMn15-xCoxNi35 （x=0, 1, 3, 5, 7） alloys were prepared by arc melting under purified argon atmosphere. The ingots were homogenized at 930℃ for 90 h followed by water quenching. The crystal structure, magnetic properties and magnetocaloric effects of the alloys were studied by X-ray diffraction （XRD） and MPMS-7-type SQUID. The results show that all samples still maintained a single γ-（Fe, Ni）-type phase structure. With the increase of the content of Co, the Curie temperatures of these alloys increased and exhibited a second-order magnetic transition from ferromagnetic （FM） to paramagnetic （PM） state near Curie temperature. The maximum magnetic entropy change and the relative cooling power of Fe50Mn10CosNi35 alloy was 2.55 J/kg.K and 181 J/kg, respectively, for an external field change of 5 T. Compared with rare earth metal Gd, FesoMnls-xCoxNi35 series of alloys have obvious advantage in resource price; their Curie temperatures can be tuned to near room temperature, maintain a relatively large magnetic entropy change at the same time and they are a type of potential magnetic refrigeration materials near room temperature.
