Roasting experiments were carried out with pure reagents as raw materials.The self-sintering behaviors of molybdenite(MoS_(2))during oxidation were investigated by thermodynamic calculation,XRD,SEM-EDS and high-temper...Roasting experiments were carried out with pure reagents as raw materials.The self-sintering behaviors of molybdenite(MoS_(2))during oxidation were investigated by thermodynamic calculation,XRD,SEM-EDS and high-temperature in situ analysis.The results indicate that the desulfurization efficiency of MoS_(2) pellet decreases with the increase of roasting temperature from 600 to 700℃,owing to the expansion of sintered area.At the very beginning of roasting,sintered layer can be rapidly formed and cover the pellet surface on the windward side,and meanwhile,MoO_(2)and Mo_(4)O_(11) intensively appear and constitute the sintered layer together with MoO_(3).Moreover,it is proven that MoO_(3)-rich products containing low-valence molybdenum oxides have low melting points,thus easy to be melted during the occurrence of exothermic reaction between MoS_(2) and O_(2),which leads to the sintering of materials.展开更多
X-ray emission from metal cathodes in glow discharge (current is up to 300 mA, voltage is 1,500-4,300 V) experiments in the spectral range from 700 eV to 6 keV has been observed. The effect has been seen with a vari...X-ray emission from metal cathodes in glow discharge (current is up to 300 mA, voltage is 1,500-4,300 V) experiments in the spectral range from 700 eV to 6 keV has been observed. The effect has been seen with a variety of different metal cathodes (including AI, Sc, Ti, V, Ni, Nb, Zr, Mo, Pd, Ta, W, and Pt), as well as with different gasses (including D2, H2, Kr, Ar, and Xe) at low pressure (3-10 Torr). We present results from a variety of diagnostics, including: pinhole camera imaging; thermo luminescent detector measurements; time-resolved scintillator measurements; and a curved mica spectrometer to register X-ray spectra. Both diffuse and collimated X-ray emission have been observed.. Diffuse emission occurs in bursts of X-rays; with up to 10^5 bursts per second, with up to 10^6 photons per burst during the discharge. Collimated X-ray emission appears in the form of beamlets directed normal to the cathodes surface with a very small angular divergence; with up to 104 bursts per second, and up to 1013 photons overall up to 20 h after discharge switch off. Based on these experimental results we propose a phenomenological model of processes.展开更多
基金financially supported by the Basic Science Center Program of the National Natural Science Foundation of China(No.72088101)the General Program of the National Natural Science Foundation of China(No.51874355)the Special Funding of China Postdoctoral Science Foundation(No.2020T130730)。
文摘Roasting experiments were carried out with pure reagents as raw materials.The self-sintering behaviors of molybdenite(MoS_(2))during oxidation were investigated by thermodynamic calculation,XRD,SEM-EDS and high-temperature in situ analysis.The results indicate that the desulfurization efficiency of MoS_(2) pellet decreases with the increase of roasting temperature from 600 to 700℃,owing to the expansion of sintered area.At the very beginning of roasting,sintered layer can be rapidly formed and cover the pellet surface on the windward side,and meanwhile,MoO_(2)and Mo_(4)O_(11) intensively appear and constitute the sintered layer together with MoO_(3).Moreover,it is proven that MoO_(3)-rich products containing low-valence molybdenum oxides have low melting points,thus easy to be melted during the occurrence of exothermic reaction between MoS_(2) and O_(2),which leads to the sintering of materials.
文摘X-ray emission from metal cathodes in glow discharge (current is up to 300 mA, voltage is 1,500-4,300 V) experiments in the spectral range from 700 eV to 6 keV has been observed. The effect has been seen with a variety of different metal cathodes (including AI, Sc, Ti, V, Ni, Nb, Zr, Mo, Pd, Ta, W, and Pt), as well as with different gasses (including D2, H2, Kr, Ar, and Xe) at low pressure (3-10 Torr). We present results from a variety of diagnostics, including: pinhole camera imaging; thermo luminescent detector measurements; time-resolved scintillator measurements; and a curved mica spectrometer to register X-ray spectra. Both diffuse and collimated X-ray emission have been observed.. Diffuse emission occurs in bursts of X-rays; with up to 10^5 bursts per second, with up to 10^6 photons per burst during the discharge. Collimated X-ray emission appears in the form of beamlets directed normal to the cathodes surface with a very small angular divergence; with up to 104 bursts per second, and up to 1013 photons overall up to 20 h after discharge switch off. Based on these experimental results we propose a phenomenological model of processes.