We numerically solve the time-dependent Ginzburg–Landau equations for two-gap superconductors using the finite-element technique. The real-time simulation shows that at low magnetic field, the vortices in small-size ...We numerically solve the time-dependent Ginzburg–Landau equations for two-gap superconductors using the finite-element technique. The real-time simulation shows that at low magnetic field, the vortices in small-size samples tend to form clusters or other disorder structures. When the sample size is large, stripes appear in the pattern. These results are in good agreement with the previous experimental observations of the intriguing anomalous vortex pattern, providing a reliable theoretical basis for the future applications of multi-gap superconductors.展开更多
A prototype thick-GEM-based cooling storage ring external-target experiment(CEE) time projection chamber(TPC) is constructed and tested with the pulsed ultraviolet laser beams. The results indicate that the prototype ...A prototype thick-GEM-based cooling storage ring external-target experiment(CEE) time projection chamber(TPC) is constructed and tested with the pulsed ultraviolet laser beams. The results indicate that the prototype TPC has a good performance in three-dimensional track resolution. In X direction the position resolution is about 0.2 mm, and in Y direction the position resolution is about 0.5 mm. The results also determine that the energy resolution is about 5.4%, which achieve the requirements of the CEE experiment and can be used to study the nuclear state equation and the quantum chromo dynamics.展开更多
A method of obtaining the large strain consolidation parameters of dredged clays considering the influence of the initial water content is investigated in this study. According to the test results of remolded clays wi...A method of obtaining the large strain consolidation parameters of dredged clays considering the influence of the initial water content is investigated in this study. According to the test results of remolded clays with high initial water contents reported by Hong et al. (2010), a relationship between the void ratio (e) and effective stress (a3 is established. Furthermore, based on the available permeability data from the literature, a new relationship between the permeability coefficient (k) and the ratio (e/eL) of the void ratio to the void ratio at the liquid limit (eL) is proposed. The new proposed expression considering the initial water content improves the e-k equation established by Nagaraj et al. (1994). Finally, the influence of the initial void ratio and effective stress on the large strain consolidation coefficient g(e) defined by Gibson et al. (1981) and k/(1 +e) in large strain analysis is discussed. The results show that, under a constant effective stress, the value of k/(1 +e) increases with the initial void ratio. The large strain consolidation coefficient shows the law of segmentation change, which decreases with the increase of the effective stress when the effective stress is less than the remolded yield stress, but increases rapidly with the effective stress when the effective stress is larger than the remolded yield stress.展开更多
This paper presents new LA-ICP-MS zircon U-Pb geochronology,whole-rock major and trace element geochemistry,and Sr-Nd isotopes systematically on porphyritic granitic and K-feldspar granitic intrusions from the Dananhu...This paper presents new LA-ICP-MS zircon U-Pb geochronology,whole-rock major and trace element geochemistry,and Sr-Nd isotopes systematically on porphyritic granitic and K-feldspar granitic intrusions from the Dananhu belt,eastern Tianshan orogenic belt(ETOB).Zircon U-Pb dating indicates that the porphyritic granitic and K-feldspar granitic plutons were formed at 357±3 and 311±3 Ma,respectively.The porphyritic granites show geochemical and isotopic characteristics(high Si O2,low Mg O and Mg^#,depleted Sr-Nd isotopic values(about 0.7034 and 6.13,respectively),with Nb/Ta(13.3–14.7)and Zr/Hf(31.0–33.9)ratios)similar to those of the crustal-derived magmas.The above characteristics suggest they were probably originated from juvenile lower crustal materials.The K-feldspar granites also have high Si O2,low Mg O and Mg^#,depleted Sr-Nd isotopic values(0.7033–0.7046 and 4.41–5.67,respectively).But some trace elements contents vary widely,with variable Nb/Ta(12.7–22.7),Zr/Hf(21.3–36.1)and Nb/La(0.38–1.07)ratios,indicating that the K-feldspar granites were formed by partial melting of juvenile lower crustal materials with old crustal materials.Combined with previous data on Carboniferous granitoids in the Dananhu belt,we infer that all the Carboniferous granitic plutons in the Dananhu belt were most likely emplaced in an island arc environment(Dananhu arc).Subsequently,a tectonic transition from oceanic subduction to post-collisional extension probably occurred in the ETOB.展开更多
We investigate a 6D generalized Randall-Sundrum brane world scenario with a bulk cosmological constant.Each stress-energy tensor Tabi on the brane is shown to be similar to a constant vacuum energy.This is consistent ...We investigate a 6D generalized Randall-Sundrum brane world scenario with a bulk cosmological constant.Each stress-energy tensor Tabi on the brane is shown to be similar to a constant vacuum energy.This is consistent with the Randall-Sundrum model,in which each 3-brane Lagrangian yielded a constant vacuum energy.By adopting an anisotropic metric ansatz,we obtain the 5D Friedmann-Robertson-Walker field equations.In a slightly later period,the expansion of the universe is proportional to the square root of time,t21,which is similar to the period of the radiation-dominated regime.Moreover,we investigate the case with two a(t)and two b(t).In a large range of t,we obtain the 3D effective cosmological constantΛeff=-2Ω/3>0,which is independent of the integral constant.Here,the scale factor is an exponential expansion,which is consistent with our present observation of the universe.Our results demonstrate that it is possible to construct a model that solves the dark energy problem,while guaranteeing a positive brane tension.展开更多
We investigate an(n+1)-dimensional generalized Randall-Sundrum model with an anisotropic metric which has three different scale factors.One obtains a positive effective cosmological constant Ωeff∼10^−124(in Planck u...We investigate an(n+1)-dimensional generalized Randall-Sundrum model with an anisotropic metric which has three different scale factors.One obtains a positive effective cosmological constant Ωeff∼10^−124(in Planck units),which only needs a solution kr≃50−80 without fine tuning.Both the visible and hidden brane tensions are positive,which renders the two branes stable.Then,we find that the Hubble parameter is close to a constant in a large region near its minimum,thus causing the acceleration of the universe.Meanwhile,the scale of extra dimensions is smaller than the observed scale but greater than the Planck length.This may suggest that the observed present acceleration of the universe is caused by the extra-dimensional evolution.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11564003 and 11865005)the Natural Science Foundation of Guangxi Province of China(Grant No.2018GXNSFAA281024)。
文摘We numerically solve the time-dependent Ginzburg–Landau equations for two-gap superconductors using the finite-element technique. The real-time simulation shows that at low magnetic field, the vortices in small-size samples tend to form clusters or other disorder structures. When the sample size is large, stripes appear in the pattern. These results are in good agreement with the previous experimental observations of the intriguing anomalous vortex pattern, providing a reliable theoretical basis for the future applications of multi-gap superconductors.
基金supported by the National Key Research and Development Program of China(Nos.2016YFA0400502 and 2015CB856904)the National Natural Science Foundation of China(Nos.U1332129,11475243,11421505,11775288 and 11405005)the ‘‘100-talent plan’’ of Shanghai Institute of Applied Physics from the Chinese Academy of Sciences(Nos.Y290061011 and Y526011011)
文摘A prototype thick-GEM-based cooling storage ring external-target experiment(CEE) time projection chamber(TPC) is constructed and tested with the pulsed ultraviolet laser beams. The results indicate that the prototype TPC has a good performance in three-dimensional track resolution. In X direction the position resolution is about 0.2 mm, and in Y direction the position resolution is about 0.5 mm. The results also determine that the energy resolution is about 5.4%, which achieve the requirements of the CEE experiment and can be used to study the nuclear state equation and the quantum chromo dynamics.
基金supported by the Innovation Program for 2011 College Graduates of Jiangsu Province(Grant No.CXZZ_0158)the National Natural Science Foundation of China(Grant No.51178107)
文摘A method of obtaining the large strain consolidation parameters of dredged clays considering the influence of the initial water content is investigated in this study. According to the test results of remolded clays with high initial water contents reported by Hong et al. (2010), a relationship between the void ratio (e) and effective stress (a3 is established. Furthermore, based on the available permeability data from the literature, a new relationship between the permeability coefficient (k) and the ratio (e/eL) of the void ratio to the void ratio at the liquid limit (eL) is proposed. The new proposed expression considering the initial water content improves the e-k equation established by Nagaraj et al. (1994). Finally, the influence of the initial void ratio and effective stress on the large strain consolidation coefficient g(e) defined by Gibson et al. (1981) and k/(1 +e) in large strain analysis is discussed. The results show that, under a constant effective stress, the value of k/(1 +e) increases with the initial void ratio. The large strain consolidation coefficient shows the law of segmentation change, which decreases with the increase of the effective stress when the effective stress is less than the remolded yield stress, but increases rapidly with the effective stress when the effective stress is larger than the remolded yield stress.
基金supported by the National Key Research and Development Program of China (No. 2016YFC0601003)the National Natural Science Foundation of China (Nos. 41903031,41421002)+1 种基金the China Postdoctoral Science Foundation (No. 2019M652431)the National Basic Research Program of China (No. 2014CB440801)
文摘This paper presents new LA-ICP-MS zircon U-Pb geochronology,whole-rock major and trace element geochemistry,and Sr-Nd isotopes systematically on porphyritic granitic and K-feldspar granitic intrusions from the Dananhu belt,eastern Tianshan orogenic belt(ETOB).Zircon U-Pb dating indicates that the porphyritic granitic and K-feldspar granitic plutons were formed at 357±3 and 311±3 Ma,respectively.The porphyritic granites show geochemical and isotopic characteristics(high Si O2,low Mg O and Mg^#,depleted Sr-Nd isotopic values(about 0.7034 and 6.13,respectively),with Nb/Ta(13.3–14.7)and Zr/Hf(31.0–33.9)ratios)similar to those of the crustal-derived magmas.The above characteristics suggest they were probably originated from juvenile lower crustal materials.The K-feldspar granites also have high Si O2,low Mg O and Mg^#,depleted Sr-Nd isotopic values(0.7033–0.7046 and 4.41–5.67,respectively).But some trace elements contents vary widely,with variable Nb/Ta(12.7–22.7),Zr/Hf(21.3–36.1)and Nb/La(0.38–1.07)ratios,indicating that the K-feldspar granites were formed by partial melting of juvenile lower crustal materials with old crustal materials.Combined with previous data on Carboniferous granitoids in the Dananhu belt,we infer that all the Carboniferous granitic plutons in the Dananhu belt were most likely emplaced in an island arc environment(Dananhu arc).Subsequently,a tectonic transition from oceanic subduction to post-collisional extension probably occurred in the ETOB.
基金Supported by the Key Program of National Natural Science Foundation of China(11535005)the National Natural Science Foundation of China(11647087 and11805097)+1 种基金the Natural Science Foundation of Yangzhou Polytechnic Institute(201917)the Natural Science Foundation of Changzhou Institute of Technology(YN1509)
文摘We investigate a 6D generalized Randall-Sundrum brane world scenario with a bulk cosmological constant.Each stress-energy tensor Tabi on the brane is shown to be similar to a constant vacuum energy.This is consistent with the Randall-Sundrum model,in which each 3-brane Lagrangian yielded a constant vacuum energy.By adopting an anisotropic metric ansatz,we obtain the 5D Friedmann-Robertson-Walker field equations.In a slightly later period,the expansion of the universe is proportional to the square root of time,t21,which is similar to the period of the radiation-dominated regime.Moreover,we investigate the case with two a(t)and two b(t).In a large range of t,we obtain the 3D effective cosmological constantΛeff=-2Ω/3>0,which is independent of the integral constant.Here,the scale factor is an exponential expansion,which is consistent with our present observation of the universe.Our results demonstrate that it is possible to construct a model that solves the dark energy problem,while guaranteeing a positive brane tension.
基金Supported by the Key Program of National Natural Science Foundation of China(11535005)the National Natural Science Foundation of China(11647087)+5 种基金Foundation for Young and Yiddle-Aged Teachers Basic Ability Improvement in Guangxi Universities(2018KY0326)Special Foundation for Science and Technology Base and Talents in Guangxi(2018AD19310)China Postdoctoral Science Foundation funded project(2019M651750)Open project of state key laboratory of solid state microstructure physics(M31037)the Natural Science Foundation of Yangzhou Polytechnic Institute(201917)the Natural Science Foundation of Changzhou Institute of Technology(YN1509)。
文摘We investigate an(n+1)-dimensional generalized Randall-Sundrum model with an anisotropic metric which has three different scale factors.One obtains a positive effective cosmological constant Ωeff∼10^−124(in Planck units),which only needs a solution kr≃50−80 without fine tuning.Both the visible and hidden brane tensions are positive,which renders the two branes stable.Then,we find that the Hubble parameter is close to a constant in a large region near its minimum,thus causing the acceleration of the universe.Meanwhile,the scale of extra dimensions is smaller than the observed scale but greater than the Planck length.This may suggest that the observed present acceleration of the universe is caused by the extra-dimensional evolution.