2.45GHzECR离子源及ECR离子源的磁场设计和计算

本文第一章介绍了高电荷态电子加旋共振（ECR）离子源发展情况，对其发展的几个方向作了一定的讨论，着重介绍了IMP高电荷态ECR离子源。第二章讨论了ECR离子源的加热原理，并讨论了低电荷态ECR离子源的加热情况。在ECR离子源中，磁场有着重要的作用，磁场场面设计和计算也ECR离子源物理设计中关键的一环。第三章讨论了ECR离子源的磁场设计和计算。在设计、加工几例磁场系统的基础上，利用计算与实测结果对离子源的磁场设计和计算作了一定程度的讨论。并使用二维POSSION、三维TOSCA程序对超导离子源进行了初步设计和计算。第四章着重讨论了两个2.45GHzECR离子源实验台。描述了一台2.45GHz单电荷态ECR离子源的结构与应用。介绍了其微波系统与磁场结构，并对该离子源的一些问题进行了讨论。在微波输入功率约600瓦，引出高压22KV，引出孔径为φ6mm，引出间隙6mm时，该离子源的总束流I(H_1~+ + H_2~+ + H_3~+)为 90mA。同时，介绍了一台2.45GHz多电荷态ECR实验台的设计。

Preparation and characterization of W-Type hexaferrite doped with La3+

A series of W-type ferrites with the composition of Ba1-xLaxCo2Fe16O27 (where, x = 0.0, 0.05, 0.10, 0.15, 020 and 0.25) were prepared by solid-state reaction method. The structure transformations of the ferrites were examined by XRD, DTA-TG and XPS, and the microwave-absorbing properties were investigated by evaluating the permeability and permittivity of materials (mu(r), epsilon(r)). The results showed that the phase-transition temperature increased with the addition of La2+ content, and a single-phase was formed at 1250 degrees C at last. Microwave properties were obviously improved as a result of the substitution of La3+ for Ba2+ at the frequency range of 0.5 similar to 18.0 GHz.

Neural network retrieval of ocean surface parameters from SSM/I data

A new algorithm based on the multiparameter neural network is proposed to retrieve wind speed (WS), sea surface temperature (SST), sea surface air temperature, and relative humidity ( RH) simultaneously over the global oceans from Special Sensor Microwave Imager (SSM/I) observations. The retrieved geophysical parameters are used to estimate the surface latent heat flux and sensible heat flux using a bulk method over the global oceans. The neural network is trained and validated with the matchups of SSM/I overpasses and National Data Buoy Center buoys under both clear and cloudy weather conditions. In addition, the data acquired by the 85.5-GHz channels of SSM/I are used as the input variables of the neural network to improve its performance. The root-mean-square (rms) errors between the estimated WS, SST, sea surface air temperature, and RH from SSM/I observations and the buoy measurements are 1.48 m s(-1), 1.54 degrees C, 1.47 degrees C, and 7.85, respectively. The rms errors between the estimated latent and sensible heat fluxes from SSM/I observations and the Xisha Island ( in the South China Sea) measurements are 3.21 and 30.54 W m(-2), whereas those between the SSM/ I estimates and the buoy data are 4.9 and 37.85 W m(-2), respectively. Both of these errors ( those for WS, SST, and sea surface air temperature, in particular) are smaller than those by previous retrieval algorithms of SSM/ I observations over the global oceans. Unlike previous methods, the present algorithm is capable of producing near-real-time estimates of surface latent and sensible heat fluxes for the global oceans from SSM/I data.

月球水冰探测进展

月球上是否存在水冰是第二次月球探测热潮中的热点问题。1994 年克莱门汀号(Clementine)环月探测器搭载的频率为2. 273 GHz 双基地雷达探测到月球南极一些地区出现同向极化增加等独特的回波特征,这些地区正好处于极地永久阴影区,表明这些地区可能存在水冰。Arecibo 天文台频率为2. 38 GHz 的地基雷达对月球极地进行制图,也得到类似结论。1998 年月球勘探者号(Lunar Prospec2tor) 环月探测器搭载的中子探测仪在月球极地永久阴影区探测到高含量的氢信号大多认为是水冰引起的。但雷达探测和中子探测结果均存在多解性。月球表面粗糙度同样可以引起雷达回波呈现出类似水冰的异常特征,而中子探测仪测量到的仅仅是氢信号而非水,而且月球勘探者号撞击月表之后并没有探测到任何的水蒸气信号。月球极地水冰存在与否、存在形式和存在数量等科学问题的回答需要对月球极地特别是永久阴影区作进一步探索。

模拟月壤研制与月壤的微波辐射特性研究

嫦娥一号绕月探测卫星上将搭载一台四通道的微波探测仪（3.0 GHz、7.8GHz、19.3 5 GHz、37 GHz）。利用其测量到的月球微波辐射亮度温度，反演月壤厚度并评估月球的氦一3资源量是嫦娥一号卫星的四大科学目标之一。本文主要包括模拟月壤的研制和月壤微波辐射特性的研究，是对月球微波辐射探测的预先研究。（l）详细概述了月壤的形成与演化、化学和矿物组成、物理力学性质等；（2）模拟月壤的研制是嫦娥工程顺利开展所必需的基础设施建设项目，本文首次提出了系列化模拟月壤的研制设想和基本方案；（3）成功研制了CAS一1模拟月壤，岩石学、矿物学和地球化学的对比表明，CAS一1模拟月壤与APollo14登月点月壤相似。并测量了其基本的化学和物理力学性质供样品使用单位参考；（4）首次提出应用聚乙烯稀释法和Liehtenecker介电混合公式，在谐振腔微扰系统上测量干燥岩石或矿物复介电常数的方法，该方法具有操作简单、所需样品量少、测量精度高等优点；（5）利用同轴终端法系统测量了120 GHz模拟月壤、模拟月岩的复介电常数，研究其随颗粒粒度和（％TiO2＋％FeO＋％Fe2O3）含量的变化规律，并比较其与地球红土的差异；（6）在对月球物质的复介电常数进行详细研究的基础上，探讨了月壤的微波辐射特性，并估算了Apollo和Luna登月点的微波辐射在月壤中的穿透深度。