无零因子四元结合代数的个数

对无零因子四元结合代数进行了讨论,证明了在同构意义下,有且仅有三个无零因子四元结合代数,它们都是一维代数.     

Research on C3N4 Superhard Compound Thin Film and Its Application

By combination of DC reactive magnetron sputtering with multiple arcplating, the alternating C3N4/TiN compound film is deposited onto HSS. The core level binding energy and contents of carbon and nitrogen are characterized by X-ray photoelectron spectrum. X-ray diffraction (XRD) shows that compound thin film contains hard crystalline phases of α-C3N4 and β-C3N4.The Knoop microhardness in the load range of 50.5-54.1GPa is measured. According to acoustic emission scratch test, the critical load values for the coating on HSS substrates are in the range of 40-80N. The metal coated with C3N4/TiN compound films has a great improvement in the resistance against corrosion. Many tests show that such a coating has a very high wearability. Compared with the uncoated and TiN coated tools, the C3N4/TiN coated tools have a much longer sutting life.     

四辊轧机轧辊接触和弯曲耦合问题研究

建立了四辊轧机工作辊和支撑辊之间接触和弯曲耦合问题的一种非线性力学模型，该模型充分考虑轧辊的接触变形和轧辊弯曲变形之间的相互影响，能更好地模拟轧辊在轧制力作用下的力学特性，采用修正迭代法求解，得到了轧辊的弯曲变形、挤压变形、接触压力、接触宽度以及它们之间相互关系等一系列结果，该模型可用于板形控制、轧机振动等问题的研究中。     

政府系统"OA"的建设与运用

政府“OA”(办公自动化)建设就似一台唱了三十余年的“大戏”，“剧本”随着政府职能转变和管理体制的变革也在不断修改与完善。笔者以“参演”十几年的实践经历，在此谈谈在推进“OA”建设进程中的认识和感受。     

四元数矩阵三种积的正定性

给出了四元数矩阵的各种正定矩阵的定义，建立了四元数矩阵的乘积，直积和圈积的正定性的一系列定理。     

李顺的改变

我校分来一名新老师，叫小黄，任四年级班主任。当他第一天查看班级学生名册时。原来兴奋、快乐的心情顿时被蒙上一层忧虑，原因是这个班上有个全校“出名”的孩子——李顺（化名）。这个孩子不仅仅好动，还会给班上造成严重的纪律麻烦，