电子相互作用和高聚物中的极化子

各种电致发光聚合物具有非简并基态.当电子和空穴注入后,形成的载流子是极化子.极化子的大小和能量决定于电子相互作用.目前大家采用Hubbard model来描述聚合物中的电子相互作用,所得到的结果与实验不符.Hubbard model和extended Hubbard model对窄能带体系是好的近似,但聚合物是宽能带,反映价键关联的非对角相互作用（在extended Hubbard model中被略去）有重要贡献,特别是在强屏蔽情况下,价键关联与Hubbard关联相互竞争,可纠正现有理论的缺陷. 关键词：     

The MAEAM Model and Anharmonic Theory for the Bulk Modulus of A1 Metal

The modified analytic embedded atom method （MAEAM） model and the anharmonic theory are used to study the bulk modulus of fcc A1 metal. The result shows that the bulk modulus can be described by a quadratic function of temperature. The result is in good agreement with the experimental data and theoretical results calculated by the first principle calculation etc. This outcome indicates that the temperature dependence of the bulk modulus for f cc A1 metal can be academically studied with the MAEAM model combining with the anharmonic theory.     

铁酸镁在苯酚-过氧化氢羟基化反应中的催化性能

苯二酚是重要的精细化工原料,用途非常广泛.我国苯二酚的生产现状是仍使用传统的、落后的生产工艺,不仅生产过程复杂,副产物多,工业后处理困难,而且生产能力极低.     

A target group tracking algorithm based on a hybrid sensor network

Traditional tracking algorithms based on static sensors have several problems. First, the targets only occur in a part of the interested area; however, a large number of static sensors are distributed in the area to guarantee entire coverage, which leads to wastage of sensor resources. Second, many static sensors have to remain in active mode to track the targets, which causes an increase of energy consumption. To solve these problems, a target group tracking algorithm based on a hybrid sensor network is proposed in this paper, which includes static sensors and mobile sensors. First, an estimation algorithm is proposed to estimate the objective region by static sensors, which work in low-power sensing mode. Second, a movement algorithm based on sliding windows is proposed for mobile sensors to obtain the destinations. Simulation results show that this algorithm can reduce the number of mobile sensors participating in the tracking task and prolong the network lifetime.     

A target group tracking algorithm for wireless sensor networks using azimuthal angle of arrival information

<正>In this paper,we explore the technology of tracking a group of targets with correlated motions in a wireless sensor network.Since a group of targets moves collectively and is restricted within a limited region,it is not worth consuming scarce resources of sensors in computing the trajectory of each single target.Hence,in this paper,the problem is modeled as tracking a geographical continuous region covered by all targets.A tracking algorithm is proposed to estimate the region covered by the target group in each sampling period.Based on the locations of sensors and the azimuthal angle of arrival(AOA) information,the estimated region covering all the group members is obtained.Algorithm analysis provides the fundamental limits to the accuracy of localizing a target group.Simulation results show that the proposed algorithm is superior to the existing hull algorithm due to the reduction in estimation error,which is between 10%and 40%of the hull algorithm,with a similar density of sensors.And when the density of sensors increases,the localization accuracy of the proposed algorithm improves dramatically.     

1-{8-甲氧基-2,3-二氢苯并[b][1,4]二噁烷-5-基}乙酮的合成

以邻香兰素为起始原料、经氧化裂解、付克反应及环合反应制得PDE-4抑制剂的中间体1-{8-甲氧基-2,3-二氢苯并[b][1,4]二噁烷-5-基}乙酮,总收率58.9%。     

有两个线性转折点时的绝对参量不稳定性

本文讨论了在弱不均匀等离子体里,当两个参量耦合方程的每一个方程都有一个线性转折点,且此两个线性转折点符号相同时,则此参量不稳定性是绝对不稳定性。解析地得到了参量不稳定性的阈值和增长率的表达式,并与数值结果作了比较,符合得很好。 关键词：