道路人工清扫扬尘中PM10污染影响因素研究

目的确定影响道路人工清扫过程扬尘大小的因素之间关系及排放因子量化模型。方法采用模拟实验方法，通过改变路面粉尘负荷q清扫强度Q以及路面粉尘湿度F等条件，对影响道路清扫过程PM10发生的主要影响因素展开研究。结果提出了中国北方城市道路人工清扫过程扬尘中PM10浓度的量化计算模型。结论粉尘含湿量对道路人工清扫扬尘量的影响最大，粉尘负荷次之，清扫强度最小。     

Block Entanglement in the Single-Hole Hubbard Model

We investigate the distribution of the entanglement of the one-dimensional single-hole Hubbard model （HM） and study the relationship between the entanglement and quantum phase transition in the model. The von Neumann entropy of a block with neighbouring spins L for a single-hole HM is calculated using the densitymatrix renormalization group. The distributions of the entanglement entropy in the ground state, as a function of block length, show a dramatic effect, i.e. effectively decoupling with the centres, no matter how the Coulomb interaction u 〉0 or u 〈0. Contrarily, for the Coulomb interaction u = 0 or close to zero, the entanglement entropy in the single-hole model reaches a saturation value for a certain block size. For a fixed size L = 40, the ground state entanglement entropy measure, as a function of u1 shows a peak corresponding to the critical quantum phase transition.     

微动开关静,动态过程与电接触过程综合模型及其模拟

以微动开关作为机电元件的典型代表，通过构造其速动机构静态，动态全过程和接触系统全过程有限元模型，并以动态模型为桥梁，将静，动态过程与电接触过程这三类不同问题联为一体，构造了综合模型，仍以ＡＫ型微动开关为例，给出了计算机模拟的综合实例。     

Compressive Behaviours of Concrete Cylinders Wrapped with 2- D Glass Fabrics

Concrete cylinders wrapped with glass fabrics of various constructions were fabricated. Compressive behaviours of cylinders with and without fabric wrapping were investigated. Comparisons of the compressive characters while using different fabrication parameters were made. It was demonstrated that the effect of the fabric reinforcement was obvious. The tensile strength of the filament used in the fabric played an important role as far as the anti-compression behaviour of the reinforced cylinders is concerned.     

一类带约束条件的集合之元素个数计数公式

本文给出了一类带不等式约束条件的集合 Bu(n,2n K)={(k1,k2…kn):{u k1≥2 u k1 k2≥2×2 … u k1 k2 … kn-1≥2(n-1) u k1 k2 … kn-1 kn=2n k n1,k1,k2…kn∈Ζ ,u,k∈Ζ}的元素个数的计算公式,并运用数学归纳方法给予了证明.     

月旦诗话(二则)

于谦与岳飞明代的民族英雄于谦以其“粉身碎骨都不怕,要留清白在人间”(《石灰》)的壮怀抵抗蒙古族瓦刺部的侵略,与南宋的岳飞齐名,赢得古今多少人的赞叹,明英宗被俘于怀来土木堡,宋徽、钦二宗被俘于汴京,两个皇朝都是在最高统治者突然陷入敌手的情况下,拥立新君,由爱国的敢于担起救亡重任的人物保卫祖国,而两个皇朝的抗敌派代表人物部不幸被     

PALAEOMAGNETIC STUDY OF SOME LATE CENOZOIC BASALT GROUP FROM DATONG REGION, SHANXI PROVINCE

In this paper, the palaeomagnetic study of the 55 oriented samples collected from some Late Cenozoic basalt group of Datong region has been carried out. The results show that the magnetic declinations of all specimens indicate eastward deviation, a shallower inclination than the present value and large amplitude of the secular variation. Site B records a short reversed episode during the late Brunhes Epoch, and it may be correlated with the Blake Event.