Particle-core coupling in 141Nd

High-spin states in 141Nd have been studied using in-beam γ-ray spectroscopic techniques via the 130Te(16O, 5nγ)141Nd reaction. The level scheme of 141Nd has been extended up to an excitation energy of 7614.5 kev including 12 new γ rays deexciting 15 new levels. According to particle-vibrator coupling and semi-empirical shell model calculations, the level structure of 141Nd can be well interpreted by coupling an h11/2 neutron-hole to the respective excited states in 142Nd core.     

A Numerical Study of Vortex and Precipitating Cloud Merging in Middle Latitudes

We mainly focus on the study of precipitating cloud merging associated with vortex merging. The vortex and precipitating cloud merging are simulated by the cloud resolving model from 0000 21 to 1800 23 July 2003. The results show that the model well simulates vortex circulation associated with precipitating clouds. It is also proven that the vortex merging follows the precipitating cloud merging although vortices show the spatial and temporal differences. The convection vorticity vector is introduced to describe the merging processes. Two merging cases are identified during the 42-h simulation and are studied.     

Nitrogen Adatom Diffusion on a Ga－Rich GaN （0001） Surface

The diffusion of N adatoms on a Ga-rich GaN(O001) surface has been studied using density-functional theory.The configuration of Ga adatoms on a Ga-rich GaN surface has been identified. The first adlayer Ga adatoms are on top of the terminating substrate Ga atoms, and the outmost adlayer Ga adatoms exist randomly at the T4 or H3 sites. A very different diffusivity of N adatoms on a Ga-rich GaN(0001) surface has been found. The excess Ga adatoms on a GaN(0001) surface reduce the diffusion barrier by 0.75eV and influence the migration path. It seems that bilayer Ga adatoms are helpful for N atom diffusion.     

利用LNG冷(火用)的准零CO2排放循环探析

本文研究利用LNG冷(火用)来完善燃用它的热机性能,既提高了效率,又能回收用LNG燃料热机的唯一主要排放-CO2.这种系统的温度区间横跨大气温度,会有很多新的特点值得探索.作为前期研究,本文建议了两种新循环,分别基于Brayton循环与超临界Rankine循环,且分别适用于LNG超临界及亚临界汽化过程.文中对此两种循环进行了分析计算与讨论,说明建议是可行的,热机效率可达60%以上,且同时基本回收所有燃烧产生的CO2.     

燃气轮机考虑经济性和环保因素的热力分析

主要符号表人，从，C，H年运行小时数对热效率风，i二1，2价格方程的系数Hu燃料低位发热量雷压比c燃料含碳百分比d贴现率，温比CO投资额J单位质量C02罚款Cj年均燃料费M比例系数下标Cth年均运行维修费N电站容量0基准值COE发电成本。运行年限C发电成本E考虑变工况的系数P单位功率价格…最佳值G空气流量马单位能量燃料价格，热效率G，燃料流量产年投资费用率1概述在进行动力机械的循环热力分析时，结合经济因素与环保因素来定量进行，是实际生产的要求，也是热力循环分析的一次创新。本文将以燃气轮机发电机组为例，对此进行首次试探，…     

Explicit analytical solutions of the anisotropic Brinkman model for the natural convection in porous media

Some algebraically explicit analytical solutions are derived for the anisotropic Brinkman model-an improved Darcy model-describing the natural convection in porous media. Besides their important theoretical meaning (for example, to analyze the non-Darcy and anisotropic effects on the convection), such analytical solutions can be the benchmark solutions to promoting the development of computational heat and mass transfer. For instance, we can use them to check the accuracy, convergence and effectiveness of various numerical computational methods and to improve numerical calculation skills such as differential schemes and grid generation ways.     

稀土与茜素红、J酸固体配合物的研究

报道了镧、镨、铕和钇与茜素红和与J酸生成的二元配合物,以及与茜素红-J酸混合配体三元配合物的制备方法。通过化学分析、红外光镨、电子光镨、核磁共振、热分析、电泳、电导和荧光等确定了化合物的组成,推测了它们的结构,并对其性质进行了研究。     

静叶内围带对轴流式压气机气动性能的影响及4500马力机车燃气轮机的热力性能

在4500马力机车燃气轮机的调试中发现静叶内围带对压气机性能、尤其是喘振边界有全面的严重影响.本文对其机理作了初步估计,并提出“围带处理”的设想.另外,还简要介绍了此机组的热力性能试验结果,包括机组的出力、效率、流量和压比随转速与温比的变化情况以及压气机与透平的特性.     

198Bi的高自旋态结构研究

利用能量为85—105MeV的¹⁶O束流,通过¹⁸⁷Re(¹⁶O,5n)反应研究了¹⁹⁸Bi的高自旋态能级结构.用6台BGO(AC)HPGe探测器和一台用于探测低能γ跃迁的平面探测器进行了γ射线的激发函数、γ-γ—t符合及γ射线的角分布测量.基于这些测量,首次建立了包括26条γ跃迁的¹⁹⁸Bi的高自旋能级纲图,确定了一个半寿命为(8.0±3.6)ns,自旋和宇称为15+的同质异能态.基于较重的双奇铋核^200—206Bi能级结构的系统性,定性地对¹⁹⁸Bi的能级结构进行了解释.