深凹边坡稳定性的数值模拟研究与可靠度分析

以有限元数值模拟为基础,应用概率论与统计论的方法,计算有限元模拟边坡节点的安全系数。采用中心点法对这些节点安全系数进行可靠度计算,从而对整个边坡的稳定性进行评价,为边坡的安全检测及施工提供依据及保证。     

从铅锌矿石中综合回收银,镉,铁选矿工艺研究

对某铅锌矿石采用优先浮选—磁选的工艺流程，分别获得了合格银精矿、含镉和银的锌精矿及合格的铁精矿，银、锌、镉、铁的回收率依次为８９．７５％、９２．３１％、８９．１０％、６６．４３％。     

非煤矿山安全标准化在安全生产中的地位和作用

深入分析了我国金属非金属矿山行业安全生产存在的主要问题及原因.全面论述了金属非金属矿山安全标准化工作的开展情况.总结了安全标准化工作取得的成绩和面临的问题.经讨论认为安全标准化工作("双S"工作)是能够使安全监管所采取的法律、行政、经济和科技手段充分发挥作用的一个"平台"和"工具",是现阶段实现金属非金属矿山行业加强安全生产"双基"工作,落实企业主体责任,提高企业本质安全程度,使安全生产形势整体根本好转的基本途径.     

煤矿企业推行强制商业保险的障碍与对策

分析了我国煤矿企业商业保险缺失的现实状况和制约因素,提出煤矿企业推行强制雇主责任险及意外险的对策：完善多层次的保险保障体系、开拓多样化的保费筹措渠道和建立多元化的风险分散机制。     

自然邻点插值在渗流场/应力场构造中的应用

计算渗流场或初始地应力场的网格一般要比实际结构分析的网格大，因此结构分析时需要将大网格中的渗流场或初始地应力场转换到小的结构分析网格中。若有大网格信息，就可以利用有限元形函数进行转换。但有时只有大网格结点坐标和相应的物理量，此时一般采用加权平均法进行转换，这种转换的精度不是太高。自然邻点插值法是基于给定结点的Voronoi图，通过自然邻点的坐标值构造插值函数，因此特别适合只有结点坐标和相应的物理量，而要将其应用于另一种网格模型的情况。给出了两种自然邻点插值的构造方式及其具体实现步骤。算例表明采用自然邻点插值构造场的精度很高。     

四旋翼飞行器航姿测量系统的数据融合方法

针对小型四旋翼飞行器航姿测量系统中MEMS器件精度低、易发散等问题,提出一种新的数据融合方法,对航姿测量系统中陀螺仪、加速度计和电子罗盘的输出数据进行融合。利用MEMS惯性测量元件搭建了一个低成本航姿测量系统,分析了姿态解算的过程和难点,采用基于梯度下降的姿态融合算法,对四元数更新方程进行了补偿。实验结果表明:与目前常用的卡尔曼滤波算法相比,基于梯度下降的数据融合算法能显著降低对处理器速度和精度的要求,能有效融合航姿测量单元的传感器数据,提高小型四旋翼飞行器的姿态测量精度。     

基于制导引信一体化的自适应起爆控制

引信与导引头一体化( GIF)设计是提高引战配合效率的有效途径.结合一般雷达导引头,首先介绍一种波控引信与硬件一体化引信进行设计,提出一体化引信起爆控制的逻辑算法流程;然后建立基于GIF信息条件下和基于引信自身信息条件下的两种弹目交会模型,并推导了最佳起爆角、起爆延时的数学表达式;最后分析计算几种弹目交会条件下,多普勒...     

Surface modification with cobalt oxide nanocluster for enhanced surface oxygen exchange reactions of GDC-LSCF membrane: fabrication,electrochemical kinetic properties,and stability

Journal of Applied Electrochemistry - Surface oxygen exchange is a critical reaction process involved in ceramic devices for energy conversion and storage such as gas separation membranes and solid...     

Towards recycling purpose: Converting PET plastic waste back to terephthalic acid using pH-responsive phase transfer catalyst

Converting polyethylene terephthalate (PET) wastes to its monomer and valuable chemicals via eco-friendly chemical method is still a challenge task. Previously, phase transfer catalysts used for alkaline hydrolysis were soluble in reaction media and hardly separated after reaction. Here, we reported several pH-responsive catalysts combined alkyl quaternary ammonium units with heteropolyacid anion for achieving stepwise product/catalyst separation and catalyst recycling. The properties of homogeneous/heterogeneous transfer behavior allow catalyst to be easily separated from reaction media by adjusting of pH value. Among them, [C₁₆H₃₃N(CH₃)₃]₃PW₁₂O₄₀ (abbreviated as [CTA]₃PW) exhibits the highest activity and the most suitable pH responsive values. Such a pH triggered switchable catalytic system not only shows good performance for depolymerization of pure PET, but also some real PET wastes such as coloured trays and PE/PET complex films could be completely degraded into terephthalic acid. Additionally, the reaction kinetics and activation energy of PET alkaline hydrolysis also studied with and without pH-responsive [CTA]₃PW.     

Hybrid CuO-Co3O4 nanosphere/RGO sandwiched composites as anode materials for lithium-ion batteries

Hybrid CuO-Co₃O₄ nanosphere building blocks have been embedded between the layered nanosheets of reduced graphene oxides with a three dimensional (3D) hybrid architecture (CuO-Co₃O₄-RGO), which are successfully applied as enhanced anodes for lithium-ion batteries (LIBs). The CuO-Co₃O₄-RGO sandwiched nanostructures exhibit a reversible capacity of~847 mA·h·g^-1 after 200 cycles' cycling at 100 mA·g^-1 with a capacity retention of 79%. The CuO-Co₃O₄-RGO compounds show superior electrochemical properties than the comparative CuO-Co₃O₄, Co₃O₄ and CuO anodes, which may be ascribed to the following reasons:the hybridizing multicomponent can probably give the complementary advantages; the mutual benefit of uniformly distributing nanospheres across the layered RGO nanosheets can avoid the agglomeration of both the RGO nanosheets and the CuO-Co₃O₄ nanospheres; the 3D storage structure as well as the graphene wrapped composite could enhance the electrical conductivity and reduce volume expansion effect associated with the discharge-charge process.