风力发电塔的自振特性分析

将风力发电塔视为带有附加质量的变截面悬臂梁,进行横向振动的自振特性分析.采用直接模态摄动法建立风力发电塔自振特性的近似求解方法,与采用梁单元模型和壳单元模型的有限元法的计算结果相比较.数值计算结果表明直接模态摄动法具有较好的精度,形成了半解析解形式.     

VERTEX-FAULT-TOLERANT CYCLES EMBEDDING ON ENHANCED HYPERCUBE NETWORKS

In this paper, we study the enhanced hypercube, an attractive variant of the hypercube and obtained by adding some complementary edges from a hypercube, and focus on cycles embedding on the enhanced hypercube with faulty vertices. Let Fu be the set of faulty vertices in the n-dimensional enhanced hypercube Qn,k （n ≥ 3, 1 ≤ k 〈≤n - 1）. When IFvl = 2, we showed that Qn,k - Fv contains a fault-free cycle of every even length from 4 to 2n - 4 where n （n ≥ 3） and k have the same parity; and contains a fault-free cycle of every even length from 4 to 2n - 4, simultaneously, contains a cycle of every odd length from n-k ＋ 2 to 2^n-3 where n （≥ 3） and k have the different parity. Furthermore, when ｜Fv｜ = fv ≤ n - 2, we prove that there exists the longest fault-free cycle, which is of even length 2^n - 2fv whether n （n ≥ 3） and k have the same parity or not; and there exists the longest fault-free cycle, which is of odd length 2^n - 2fv ＋ 1 in Qn,k - Fv where n （≥ 3） and k have the different parity.     

故障加强超立方体中的路和圈

本论文研究了含故障点的加强超立方体中路和圈的嵌入问题.利用数学归纳法,获得了故障加强超立方体中的路和圈,推广了超立方体中点容错路和圈嵌入的结果.     

β分子筛的酸性和孔道对α-蒎烯催化转化性能的影响

高等物理化学实验是我校理科化学专业学生的必修课,催化剂的制备与表征是其中不可或缺的部分。本实验是对高等物理化学教学实验“NH3-TPD法分析材料的酸性质”及“催化剂活性及选择性的测定”的改进,改进后方案将原实验方案中考察单一催化剂上反应物在不同反应温度和反应时间下的转化率和选择性,更改为具有不同孔道结构和酸量的三种催化剂在同一反应条件下的催化性能对照,同时结合仪器分析实验“N2物理吸附”等相关化学实验,使学生连贯地学习催化剂的制备、改性与表征技术,更清晰地认识影响催化剂催化性能的影响因素。旨在使学生将在多门课程中所学习到的理论知识融会贯通,深入了解β分子筛在较大尺寸反应物分子的转化反应中发挥催化作用的原理。