System optimization study of hybrid K-edge/XRF densitometer for uranium-plutonium solution measurement.

In this paper, a comprehensive hybrid K-edge/XRF densitometer (HKED) device model is constructed using MCNP simulation. After the modeling process, a systematic simulation study is conducted to analyze the physical parameters and material selection of KED and XRF. The simulation results reveal that the optimal parameters for the X-ray tube are an X-ray source voltage of 160 kV and a 1 mm Fe filter.

Electron Spin Resonance of the Interacting Spinon Liquid.

We report experimental verification of the recently predicted collective modes of spinons, stabilized by backscattering interaction, in a model quantum spin chain material. We exploit the unique geometry of uniform Dzyaloshinskii-Moriya interactions in K_{2}CuSO_{4}Br_{2} to measure the interaction-induced splitting between the two components of the electron spin resonance (ESR) response doublet. From that we directly determine the magnitude of the "marginally irrelevant" backscattering interaction between spinons for the first time.

Application of the Monte Carlo Library Least-Squares (MCLLS) approach for chromium quantitative analysis in aqueous solution.

In the present work, a new in-situ prompt gamma-ray neutron activation analysis (PGNAA) setup was developed for the quantitative measurement of chromium (Cr) in aqueous solutions which consists of a 4" × 4″ inch Bismuth Germanate detector and a 300 mCi Americium-beryllium neutron source. A series of standard samples were prepared by dissolving Cr compounds in deionized water of analytical pure grade and measured using the in situ PGNAA setup. Quantitative spectrum analysis was conducted using Monte Carlo Library Least-Squares approach (MCLLS).

Methods of kernel parameter calculation for stabilization technology of radon concentration in a closed radon chamber.

A radon chamber is a standard apparatus for experimental research of radon that can simulate ambient conditions such as atmosphere, ground surface and subsurface, and the dynamic stabilization technology of radon concentration in a radon chamber is the core technology of radon chamber research. In this paper, an attenuation method was proposed based on a radon leakage attenuation model for calculation of leak rate, a kernel parameter of the stabilization technology of radon concentration in a closed radon chamber, as well as a bench method based on a radon replenishment model for calculation of the effective generation rate at radon source, another kernel parameter of stabilization technology. In this study, the present methods were applied to parameter calculation in an HD-6-type small/medium-sized radon chamber, achieving an excellent application effect.