Validation of source biasing method for its use in CSNS beamline shielding calculation.

The Chinese spallation neutron source (CSNS) is a high-performance pulsed neutron source, having 20 neutron beamlines for neutron scattering instruments. The shielding design of these beamlines is usually needed for Monte Carlo (MC) calculation, and the use of variance reduction methods is critical to carrying out an efficient, reliable MC shielding calculation. This paper discusses the source biasing method based on actual source term and geometry model of a CSNS neutron beamline.

[X-ray diffraction quantitative analysis with polynomial-fit method for polycrystalline materials].

The polynomial-fit method for XRD quantitative analysis of polycrystalline materials is presented in this paper, which combines a mathematic function model with computer technology. Based on the construction of diffraction peak mathematic function model, the XRD atlases from experiments were analyzed by means of polynomial whole pattern fitting to the spectral lines using computer software, then the integral intensities of every peak and weight percentages of each phase could be obtained accurately. This paper mainly includes three parts: 1.