摘要：Due to their unique surface chemistry,highly adjustable metal components,hydrophilicity,and high carrier concentrations,MXenes are applied in a variety of *** to other two-dimensional(2D)materials,building heterostructures with additional materials to form a 3D porous architecture for MXenes can significantly enhance their functionality and ***,the open structures and well-defined pathways of these 3D structured MXenes can improve ionic and electronic transport,thereby promoting their applications in electrochemical energy storage,sensing,catalysis,and *** this review,the recent efforts made on preparing 3D porous MXenes with heterostructures,focusing on MXenes/C,MXenes/inorganics,and MXenes/polymers were *** discussion covers aspects ranging from the design to synthesis of 3D porous MXenes,and their applications in photocatalysis,environmental monitoring and electrochemical energy *** review is concluded by presenting the prospects and insights on exploring the relationships between the porosity formation mechanisms,properties and applications of the 3D porous MXenes *** review can provide meaningful guidance for the design,fabrication and application of 3D porous MXenes in high-performance materials and devices.

摘要：结合工程实例,综合地质条件、设计和施工情况分析高地应力软岩隧道塌方事故发生原因,详细阐述了实际工程中塌方处置措施,并结合《铁路隧道设计规范》对处置后隧道二次衬砌进行安全性评价。通过隧道内塌方体土方量估算塌腔高度,计算出塌方造成的松散岩土体作用在隧道衬砌结构上的竖向荷载,采用荷载-结构模型,得出二次衬砌结构内力,对二次衬砌进行安全性评价。根据评价结果,通过注浆固结塌方体、设置套拱及拱部钢花管注浆加固临近段支护结构,采用拱部管棚加固+局部径向注浆+注浆回填处理塌腔,之后再进行短进尺拆换塌方段支护结构的方法,能有效处置高地应力软岩隧道塌方,保证施工安全和结构可靠。

摘要：岩溶形成的空腔会造成隧道附近区域地应力场变得复杂,开挖过程中的扰动会进一步加剧复杂的地应力场。文章以重庆某公路隧道为依托,利用数值模拟建立三维模型,全面地研究了当岩溶空腔分别位于隧道的拱顶、拱底、边墙时对隧道的影响,得到了围岩位移、支护结构内力及围岩塑性区在不同位置空腔影响下的详细变化规律。其研究结果可为类似岩溶空腔隧道的设计和施工提供参考。

摘要：设计了一种基于脉冲推力/气动力控制的高速动能导弹复合控制系统。首先建立了滚转导弹的数学模型,然后对脉冲推力/气动力复合控制系统工作流程进行了描述,设计了脉冲发动机点火策略;最后通过仿真算例对复合控制方法进行了验证和分析。仿真结果表明:设计的复合控制系统能够有效降低滚转高速动能导弹的发射初始扰动,具有一定的应用价值。