8,837 research outputs found
Theoretical study of the synthesis of superheavy nuclei with Z= 119 and 120 in heavy-ion reactions with trans-uranium targets
By using a newly developed di-nuclear system model with a dynamical potential
energy surface---the DNS-DyPES model, hot fusion reactions for synthesizing
superheavy nuclei (SHN) with the charge number Z = 112-120 are studied. The
calculated evaporation residue cross sections are in good agreement with
available data. In the reaction 50Ti+249Bk -> (299-x)119 + xn, the maximal
evaporation residue (ER) cross section is found to be about 0.11 pb for the
4n-emission channel. For projectile-target combinations producing SHN with
Z=120, the ER cross section increases with the mass asymmetry in the incident
channel increasing. The maximal ER cross sections for 58Fe+244Pu and 54Cr +
248Cm are relatively small (less than 0.01 pb) and those for 50Ti+249Cf and
50Ti+251Cf are about 0.05 and 0.25 pb, respectively.Comment: 6 pages, 5 figures; Phys. Rev. C, in pres
Simulated and measured soil wetting patterns for overlap zone under double points sources of drip irrigation
Water resource scarcity is a serious problem hampering agricultural development in the arid and semiarid region. Drip irrigation is one of the most useful methods that is widely used in the arid and semiarid region. Intersection is a however, common event under drip irrigation and the crops are always planted in the overlap zone, hence a suitable design and operation of the system is very important for crop yield. In this study, experimental and simulated soil wetting pattern of overlap were investigated for drip irrigation at different emitter discharge, irrigation volume and emitter spacing, respectively. Simulations of the water content and wetting front were close to the observed data. To evaluate the effects of various parameters on wetting, additional simulations were carried out with HYDRUS. After the simulation under the HYDRUS environment, we therefore recommended a larger irrigation volume, larger wetting pattern; and when the emitter spacing is shorter, then the wetting patterns should be larger. Due to the heterogeneity of soil texture, the horizontal and vertical distance are almost uniformly in the loam and silt, inversely in loamy sand.Key words: Drip irrigation, HYDRUS, intersection, soil wetting pattern
Deformation monitoring of high-latitude permafrost region of northeastern China with time series inSAR technique
Abstract. Permafrost distributed in northeast China is the only high-altitude permafrost in China. The deformation monitoring over this permafrost region is of great importance to local climate change and ecological environments. This study focuses on the deformation monitoring of high-latitude permafrost in northeast China with time series InSAR technique. The spatial distribution characteristics, the annual deformation rates and the temporal deformation evolutions of permafrost could be retrieved from multi-temporal InSAR processing with Sentinel-1 TOPS datasets. This work concludes that time series InSAR technique could help to retrieve a comprehensive and reliable permafrost deformation, while a long time-series of displacements facilitated to better understand permafrost kinematics.</p
The ground state entanglement in the model
In this paper, we investigate spin entanglement in the model defined on
a -dimensional bipartite lattice. The concurrence, a measure of the
entanglement between two spins, is analyzed. We prove rigorously that the
ground state concurrence reaches maximum at the isotropic point. For
dimensionality , the concurrence develops a cusp at the isotropic
point and we attribute it to the existence of magnetic long-range order.Comment: 5 pages, 2 figure
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