Glacial Runoff Likely Reached Peak in the Mountainous Areas of the Shiyang River Basin,China

Glacier runoff in mountain areas of the Shiyang River Basin(SRB), Qilian Mountain, western China is important for the river and water supply downstream. Small glaciers with area of less than 1km2 are dominant(87%) in the SRB. A modified monthly degree-day model was applied to quantify the glacier mass balance, area, and changes in glacier runoff in the SRB during 1961–2050. The comparison between the simulated and observed snow line altitude, annual glacier runoff, and mass balance from1961 to 2008 suggests that the degree-day model may be used to analyze the long-term change of glacier mass balance and runoff in the SRB. The glacier accumulation shows a significant(p<0.01) decreasing trend of-0.830 mm a-1. The mass balance also shows a significant(p<0.01) decreasing trend of-5.521 mm a-1. The glacier total runoff has significantly(p<0.05)increased by 0.079 × 105 m3 from 1961 to 2008. The monthly precipitation and air temperature are projected to significant(p<0.005) increase during2015 to 2050 under three different scenarios. The ablation is projected to significant(p<0.001) increase,while the accumulation has no significant(p=0.05)trend. The mass balance is projected to decrease, theglacier area is projected to decrease, and the glacier runoff depth is projected to increase. However, the glacier total runoff is projected to decrease. These results indicate that the glacier total runoff over glacier areas observed in 1970 reached its peak in the 2000 s. This will exacerbate the contradiction between water supply and downstream water demands in the SRB.

Analysis of Enhanced Laser-Induced Breakdown Spectroscopy with Double Femtosecond Laser Pulses

In this paper, an experimental study of collinear geometry double-pulse femtosecond LIBS was performed on a Ni sample in ambient air in an effort to clarify the contributing processes responsible for the signal enhancement observed in comparison with the single-pulse case. Doublepulse LIBS spectra show a very clear enhancement when an optimum inter-pulse delay was used. The influences of the inter-pulse delay between two pulses on the LIBS signal intensity, electron temperature and density were investigated. It is most remarkable that the evolutions of signal enhancement and electron temperature versus the inter-pulse delay showed the same behavior and revealed two main regimes of interaction. These results provide additional insight into the possible emission enhancement mechanisms in the double pulse configuration.

Nucleon-nucleon interactions in the double folding model for fusion reactions

Nucleus-nucleus potentials are determined in the framework of double folding model for M3Y-Reid and M3Y- Paris effective nucleon-nucleon （NN） interactions. Both zero-range and finite-range exchange parts of NN interactions are considered in the folding procedure. In this paper the spherical projectile-spherical target system 16O＋^2008Pb is selected for calculating the barrier energies, fusion cross sections and barrier distributions with the density-independent and density-dependent NN interactions on the basis of M3Y-Reid and M3Y Paris NN interactions. The barrier energies become lower for Paris NN interactions in comparison with Reid NN interactions, and also for finite-range exchange part in comparison with zero-range exchange part. The density-dependent NN interactions give similar fusion cross sections and barrier distributions, and the density-independent NN interaction causes the barrier distribution moving to a higher position. However, the density-independent Reid NN interaction with zero-range exchange part gives the lowest fusion cross sections. We find that the calculated fusion cross sections and the barrier distributions are in agreement with the experimental data after renormalization of the nuclear potential due to coupled-channel effect.

Monte Carlo studies of micromegas as a neutron detector and its track reconstruction

In this paper a two dimensional readout micromegas detector with a polyethylene foil as converter was simulated on GEANT4 toolkit and GARFIELD for fast neutron detection. A new track reconstruction method based on time coincidence technology was developed in the simulation to obtain the incident neutron position. The results showed that with this reconstruction method higher spatial resolution was achieved.

A Remark on the Cauchy Problem of 1D Compressible Navier-Stokes Equations with Density-dependent Viscosity Coefcients

This paper is concerned with the Cauchy problems of one-dimensional compressible Navier-Stokes equations with density-dependent viscosity coefcients.By assumingρ0∈L1（R）,we will prove the existence of weak solutions to the Cauchy problems forθ〉0.This will improve results in Jiu and Xin’s paper（Kinet.Relat.Models,1（2）：313–330（2008））in whichθ〉12is required.In addition,We will study the large time asymptotic behavior of such weak solutions.