Recent progress of green sorbents-based technologies for low concentration CO2 capture

The increased concentration of CO₂ due to continuous breathing and no discharge of human beings in the manned closed space, like spacecraft and submarines, can be a threat to health and safety. Effective removal of low concentration CO₂ from the manned closed space is essential to meet the requirements of long-term space or deep-sea exploration, which is an international frontier and trend. Ionic liquids (ILs), as a widespread and green solvent, already showed its excellent performance on CO₂ capture and absorption, indicating its potential application in low concentration CO₂ capture. In this review, we first summarized the current methods and strategies for direct capture from low concentration CO₂ in both the atmosphere and manned closed spaces. Then, the multi-scale simulation methods of CO₂ capture by ionic liquids are described in detail, including screening ionic liquids by COSMO-RS methods, capture mechanism by density functional theory and molecular dynamics simulation, and absorption process by computational fluid dynamics simulation. Lastly, some typical IL-based green technologies for low concentration CO₂ capture, such as functionalized ILs, co-solvent systems with ILs, and supported materials based on ILs, are introduced, and analyzed the subtle possibility in manned closed spaces. Finally, we look forward to the technology and development of low concentration CO₂ capture, which can meet the needs of human survival in closed space and proposed that supported materials with ionic liquids have great advantages and infinite possibilities in the vital area.     

Effect of CuSO4 on the Hydromechanical Behavior of Compacted Tailings

Laboratory tests, including compressibility, permeability, and microstructure tests, were conducted on tailings samples using custom-designed test apparatus to investigate the effect of metal contamination (Cu²⁺) on the hydromechanical behavior of compacted tailings. Infiltrating samples with various dry densities with distilled water or CuSO₄ solution at various concentrations showed that the void ratio of compacted tailings decreased with increased dry density. An increase in the metal contaminant concentrations from 0 to 0.1 mol/L increased the compression coefficient of the tailings from 0.14 to 0.84 MPa^?1 under a vertical load of 0.01 to 2.0 MPa, while the yield stress of the tailings decreased from 204.3 to 98.7 kPa, respectively. The linear relationship between permeability coefficient (k) and void ratio (e) is described by k?=???6.48?+?17.17e. Microstructure test results showed that the diffusion double layer thinned, and the surface potential decreased, indicating that the contaminant of Cu²⁺ enhanced the compressibility and permeability of the tailings. The microstructure test results also showed that the amount of fine-grained soil in the copper tailings was significantly less after the hydromechanical test. Therefore, the permeability and compressibility of copper tailings increased. The experimental results are in good agreement with the estimated results.

     

自制简易注浆器在境外隧洞工程施工中的应用

在乌干达卡鲁玛尾水隧洞工程前期施工中,由于国内注浆设备尚未到达,乌干达及周边国家难于买到,为了解决前期锚杆、小导管注浆等问题,项目部利用已进场的管材及乌干达能买到的材料、物资,成功地自行研制了简易锚杆、小导管注浆器,并得到了实际应用,从而保证了工程顺利开工,并取得了较好的经济效益。实际应用表明:该设备具有制作简单、操作方便、经济实用的特点。     

基于强度场的八球万向节内套结构与静强度设计匹配研究

为了对八沟道等速万向节内套进行结构和静强度设计,从钢球选型出发,对八沟道等速万向节内套进行了结构参数正向设计.对内套危险截面进行了全场静强度设计,以理想静强度场为目标,定量匹配了危险截面静强度的材料、热处理,并对全场静强度设计进行了定量评价.使用MTS静扭转试验机对等速万向节总成进行了静强度扭转试验,并用显微硬度计对内套进行了显微硬度试验以验证理论,结果表明按照基于强度场的机械结构和零部件的静强度设计与匹配方法设计的八沟道等速万向节星形套能够满足强度和功能需求.     

一种汽车顶盖抗雪压动态仿真分析方法

目前顶盖雪压静态仿真分析方法的雪压计算值与测试值存在偏差,并且不能反映顶盖实际变形的位置和整体变形模式。为改进静态仿真分析方法,提出一种非线性显式计算的动态仿真分析方法,并以某乘用车为例,通过试验验证了其可靠性及有效性,为顶盖的研发设计提供了参考。     

Microstructures and mechanical properties of B4C-TiB2-SiC composites fabricated by ball milling and hot pressing

B₄C-TiB₂-SiC composites were fabricated via hot pressing using ball milled B₄C, TiB₂, and SiC powder mixtures as the starting materials. The impact of ball milling on the densification behaviors, mechanical properties, and microstructures of the ceramic composites were investigated. The results showed that the refinement of the powder mixtures and the removal of the oxide impurities played an important role in the improvement of densification and properties. Moreover, the formation of the liquid phases during the sintering was deemed beneficial for densification. The typical values of relative density, hardness, bending strength, and fracture toughness of the composites reached 99.20%, 32.84?GPa, 858?MPa and 8.21?MPa?m^1/2, respectively. Crack deflection, crack bridging, crack branching, and microcracking were considered to be the potential toughening mechanisms in the composites. Furthermore, numerous nano-sized intergranular/intragranular phases and twin structures were observed in the B₄C-TiB₂-SiC composite.     

基于Bayes方法的Al-Mg-Mn合金断裂韧度研究

基于Bayes方法研究了Al-5.2Mg-0.7Mn-0.20Sc-0.1Zr合金的平面应变断裂韧度。结果表明,Al-5.2Mg-0.7Mn-0.20Sc-0.1Zr合金热轧板在L-T和T-L取向KIC值分别为32.66和32.03 MPa·m1/2,平面应变断裂韧度各向异性差别较小。     

潮流能水平轴水轮机在剪切来流下的水动力分析

采用基于计算流体力学方法的全尺度数值模拟计算,建立了适用于潮流能水轮机模拟的剪切来流环境,通过数值计算结果,对潮流能水轮机随时间变化的宏观力和流场特征进行了系统分析,探索水轮机在复杂工况下的水动力特性规律。结果表明,水轮机整个叶轮的总体平均受力在剪切流工况中未受到明显影响; 单个叶片的瞬态轴向力系数和瞬态轴向扭矩系数在旋转周期内出现了明显的周期性变化,且周期性变化幅值随转速增大而增大; 非定常的瞬时轴向扭矩和力的周期性振荡容易引起单个叶片的结构性振动,可能对水轮机的机械结构造成影响。