Structural and electronic properties of Si termination, O-middle termination, and O-rich terminations of a quartz (001) surface as well as water molecule adsorption on it were simulated by means of density functional theory (DFT). Calculated results show that the O-middle termination exposing a single oxygen atom on the surface is the most stable model of quartz (001) surface, with the lowest surface energy at 1.969 J·m⁻², followed by the O-rich termination and Si termination at 2.892 J·m⁻² and 2.896 J·m⁻², respectively. The surface properties of different terminations mainly depend on the surface-exposed silicon and oxygen atoms, as almost all the contributions to the Fermi level (E_F) in density of states (DOS) are offered by the surface-exposed atoms, especially the O2p state. In the molecular adsorption model, H₂O prefers to adsorb on the surface Si and O atoms, mainly via O₁–H₁ bond at 1.259 Å and Si₁–O_w at 1.970 Å by Van der Waals force and weak hydrogen bond with an adsorption energy of −57.89 kJ·mol⁻¹. In the dissociative adsorption model, the O-middle termination is hydroxylated after adsorption, generating two new Si–OH silanol groups on the surface and forming the O_wH₂···O₄ hydrogen bond at a length of 2.690 Å, along with a large adsorption energy of −99.37 kJ·mol⁻¹. These variations in the presence of H₂O may have a great influence on the subsequent interfacial reactions on the quartz surface.

A stable dispersion of fine mineral particles in an aqueous system facilitated by dispersants is an essential prerequisite for their successful separation. We investigated the dispersion stability and mechanism of suspensions of aqueous collophane and quartz fines (10 µm) in the presence of sodium hexametaphosphate (SHMP), sodium silicate or sodium carbonate using the sedimentation balance method, zeta potential measurements, contact angle measurements, micro-flotation tests and theoretical calculation of Extended-DLVO (Derjaguin-Landau-Verwey-Overbeek). The results showed that three dispersants significantly enhanced the dispersion stability of collophane in the following descending order SHMP > sodium silicate > sodium carbonate. This is because they increased the zeta potential of collophane in the same order; meanwhile, the SHMP made the collophane more hydrophilic compared to two other dispersants. These results illustrated that the dispersion stability was attributed to electrostatic repulsion and hydration repulsion and that the hydration repulsion had a greater influence on the stability than electrostatic repulsion based on the calculation of Extended-DLVO. However, the quartz suspension always maintained a stable dispersion in the absence or presence of dispersants, since there was a higher zeta potential and stronger hydrophilicity for natural quartz. These provide a theoretical direction for the dispersion of fine-disseminated siliceous phosphorites and phosphate slimes in separations.

We provide a principal Hugoniot of cryogenic liquid deuterium at a pressure of $27<P<240$ GPa, with reflected-shock data of up to $\sim 830$ GPa. The maximum density reaches $\sim 1.49$ $\mathrm{g}/{\mathrm{cm}}^3$, about 8.7 times the initial density. Our independent principal Hugoniot experimental data broadly support the wide-regime equation of state (WEOS) model, which well matches Fernandez-Pañella et al. [ Phys. Rev. Lett. 122, 255702 (2019)] and Knudson et al. [ Phys. Rev. Lett. 118, 035501 (2017)] experimental data over the observed pressure range up to 550 GPa, and most of three sets of reflected shock data are in accordance with our theory up to 1 TPa. Our high-precision experimental results establish an important benchmark equation of state of deuterium and conform to the WEOS model quite well. Our work is useful for the development of the high-pressure response of hydrogen's isotopes, directly related to inertial confinement fusion, planetary science, and metallization.

任意反射面速度干涉仪(VISAR)具有很高的测试精度, 能实现冲击波速度、粒子速度的连续测量, 是目前冲击波传播相关物理实验的主要诊断设备. 神光II高功率激光装置上的速度干涉仪其空间分辨率优于7 m, 靶面视场约为1 mm, 探针光脉冲宽度约为 60 ns, 能满足各类冲击波相关实验的诊断. 该VISAR系统用偏振分光镜和波片系统组成了能量调节系统, 极大地方便了探针光能量和条纹相机匹配的调节; 利用新颖的探针光引入系统, 极大地提高了探针激光的能量利用率 (相对其他方法, 能量利用率提高了3倍). 该速度干涉仪已成功应用于状态方程实验、等熵压缩实验和冲击波追赶实验. 本文利用激光脉冲整形技术获得了无冲击压缩实验图像, 利用石英作为标准材料获得了聚苯乙烯 (CH)的Hugoniot数据, 利用双脉冲激光获得了石英材料中冲击波追赶 的实验图像并与理论模拟进行了对比, 实验和模拟符合得比较好. 实验结果表明, 神光II装置上的速度干涉仪能满足不同时间尺度(亚ns几十ns) 冲击波传播相关物理实验的诊断, 为进一步开展CH的高精度Hugoniot参数测量、 高压无冲击压缩实验和冲击波时空整形实验奠定了基础.