分类: 核科学技术 >> 核材料与工艺技术 提交时间: 2023-06-18 合作期刊: 《Nuclear Science and Techniques》
摘要: Porous membranes were prepared using the phase inversion method from poly(vinylidene fluoride)-graft-poly(N-vinyl pyrrolidone) (PVDF-g-PVP) powders, which were synthesized via -ray induced graft polymerization (pre-irradiation). Chemical compositions, thermal behavior, morphology and hydrophilicity of the membranes were characterized by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, element analysis, thermalgravimetric analysis, differential scanning calorimetry, scanning electron microscopy and contact angle measurements, respectively. Permeation experiments were conducted to evaluate the water flux, and the dynamic BSA fouling resistance performances were investigated, too. All the experimental results indicate that the PVDF-g-PVP membranes demonstrate better separation performances over the pristine PVDF membrane.
分类: 物理学 >> 核物理学 提交时间: 2023-06-18 合作期刊: 《Nuclear Science and Techniques》
摘要: How the initial fluctuation affects on the elliptic flow is investigated by investigating the rapidity, transverse 4-velocity, centrality dependencies of elliptic flow for Au+Au at 1 GeV/A with the help of an Isospin Quantum Molecular Dynamics (IQMD). In addition, we compare the flow calculated with respect to participant plane created by the initial geometry in coordinate space with the flow reconstructed by the experimental event-plane method, and compare the flow with the experimental data of the FOPI collaboration. It shows that there exists some discrepancy between the flows reconstructed by the above two methods.
分类: 核科学技术 >> 粒子加速器 提交时间: 2023-06-18 合作期刊: 《Nuclear Science and Techniques》
摘要: In this paper, in order to achieve the output signal processing of cavity beam position monitor (CBPM), we develop a digital intermediate frequency receiver architecture based signal processing system, which consists of radio frequency (RF) front end and high speed data acquisition board. The beam position resolution in the CBPM signal processing system is superior to 1 m. Two signal processing algorithms, fast Fourier transform (FFT) and digital down converter (DDC), are evaluated offline using MATLAB platform, and both can be used to achieve, the CW input signal, position resolutions of 0.31 m and 0.10 m at 16 dBm. The DDC algorithm for its good compatibility is downloaded into the FPGA to realize online measurement, reaching the position resolution of 0.49 m due to truncation error. The whole system works well and the performance meets design target.