Time-resolved PL Spectra Study of Ordered Ga_(0.52)In_(0.48)P Alloys

【中文摘要】 在室温和低温液氮下 ,研究了有序和无序 Ga0 .52 In0 .4 8P的时间分辨发光谱。对实验结果的拟合表明 ,有序 Ga0 .52 In0 .4 8P的发光呈双指数规律衰退。其中快过程对应着有序区域上载流子的复合 ,慢过程则对应着有序区域和无序区域的空间分离中心上载流子的复合。无序 Ga0 .52 In0 .4 8P的发光在室温下呈单指数规律衰退。同时从低温下的时间分辨发光谱还可以看出有序样品的发光峰随着延迟时间的变长而蓝移 ,说明低温下在有序 Ga0 .52In0 .4 8P中存在着载流子从无序区域到有序区域的转移 【英文摘要】 The time resolved photoluminescence(TRPL) spectra of ordered and disordered Ga 0.52 In 0.48 P alloys grown by MOVPE were investigated.The least square fitting of the luminescence decay spectra of ordered alloys shows that there exist two exponential processes:The short lifetime process was corresponding to the high energy peak in PL spectra which is attributed to the recombination of the carriers in the ordered domains and the long lifetime process was corresponding to the low energy peak in the P...国家自然科学基金 (编号:69776011); 福建省自然科学基金 (编号:A9910004和 A0110007

REMOTE SENSING NDVI LST TVDI

基于MODIS的生态信息提取是反演环境参数的一种有效方法，本文提出了一种遥感监测干旱的模型，它可以用来计算从裸地、稀疏植被，高植被覆盖等大部分地貌类型条件下的土壤水分状况。此模型在新疆石河子典型区域的应用中，得到了令人满意的效果。它不仅能对区域的干旱状况作出相对的判断，还能从具体量化指标上给出定量化的描述。本文阐述了MODIS生态信息的提取技术，它是基于大中尺度遥感生态监测的有效手段，对于新疆具有重要的意义。更进一步的工作是对模型的校正和检验，它将提高模型的整体隆能。本文共分为六章，第一章绪论主要讨论了MODIS生态信息提取的目的和需求，详细叙述了它在生态监测中的必要性。回顾和总结了NDVILST，土壤水分监测模型的应用及其存在的问题，指出了建立遥感MODIS生态信息提取模型的目标。第二章研究了MODIS文件格式、仪器特性和1B数据特点，提出了MODIS数据基础处理的方法和流程，通过一系列定标和几何纠正处理了典型区2003年所有的MODIS数据。第三章研究了NDVI在生态监测终中的作用，分析了NDVI的理论基础，方法和多时相合成算法，通过NDVI各分类统计面积及提取不同景观样区NDVI的手段，对石河子地区的生态变化提出分析及解释。广的MODIS分裂窗技术来提取LST，并确定了提取的最佳波段组合。被指数特征空间的详细分析，提出了一种基于Ts/NDVI简化空间模型的TVDI渭数。并对新疆典型区域‘石河子地区进行了实例分析，同时利用地面土壤水分监测点的数据与遥感反演的干旱指数进行了对比分析。结果表明，土壤水分与植被干旱指数并不是一一对应的关系。植物的干旱指数和植被类型，植被生长状况有关，与土壤水分的对应关系尚待进一步研究，但植被干早指数确能较好的反映植物的缺水状况。第六章是总结全文，并对今后MODIS生态信息提取模型的发展进行了展望。It is a kind of effective method to perform the environmental parameter instead that the ecological information based on MODIS is drawn, this text has proposed a kind of remote sensing monitors the dryness model, it can be used for calculating the soil moisture states under the type condition of most ground from nakedly to high vegetation. This model has got the satisfactory result in the application of typical area of Shihezi of Xinjiang. It not only can dryness state in area make relative judgement, can also provide description that ration take from concrete quantization index. This text has explained the extraction technology of MODIS ecological information, it is an effective means to monitor on the basis of the remote sensing ecology of large and middle scale, have important meanings to Xinjiang. Further work should do to correct and inspection to model, it can raise model' performance. This text is divided into six chapters altogether, the purpose and demand that MODIS ecological information extract technological mainly be discussed in chapter one, and have narrated its necessity in the ecology in detail . Having reviewed and summarized the application of the NDVI, LST, the soil moisture monitors model and existing problem, have pointed out the goal of drawing model of remote sensing MODIS ecological information. Chapter two studied MODIS file layout, the characteristic of the instrument and IB data characteristic , has put forward the method and procedure to deals with the MODIS data, have finalized all MODIS data in 2003 .of the typical district with a series of. revise and geometry correction. Chapter three studied NDVI function in the ecology, it is analysed that theoretical foundation , method and multi-time phases of NDVI algorithms, through drawing NDVI of the different landscape and NDVI statistic of classification area, the analysis and explain has be proposed to the ecological change of the area of Shihezi. Chapter four research the method of the LST remote sensing model in detail, through reviewing and comparing various kinds of algorithms, select MODIS the split windows technology to draw LST, and confirmed the best wave band in the model. Chapter five studied the remote sensing dryness monitored models based from the surface temperature / the vegetation index, through analyzing the space in detailed, propose one simplify TVDI index, space of model on the basis of Ts/NDVI to surface temperature / vegetation index characteristic. And has carried on the instance analysis of the typical area of Xinjiang - Shihezi area, utilize the ground soil moisture data to compare and analyze with the dryness index. The result indicates that, the soil moisture are with little relations of the dryness index. TVDI and vegetation type , vegetation of plant grow state have something to do further research by corresponding relation . But vegetation arid index really can better reflection state of lack of water of plant. Chapter six summarize the full text, and has looked forward to the development that MODIS ecological information extraction model in the future

失重飞机搭载气／液两相流实验研究

利用俄罗期ＩＬ－７６ＭＤＫ失重飞机对失重条件下方形截面（１２ｍｍ×１２ｍｍ）管道内气／液两相流动进行了实验研究，观测到失重条件下气／液两相泡状流、弹状流和环状流等三种主要流型，同时得到了气、液两相介质的流量、温度和实验段内压力等结果，分析了失重条件下方形截面管道内气／液两相流型转换的条件

一种综合评价氨态氮对水生动物威胁的方法

本发明涉及评价对水生动物威胁的方法，具体的说是一种综合评价氨态氮对水生动物威胁的方法。以测定水体中氨氮本身毒性和亚硝酸盐毒性的总和作为综合评价氨态氮对水生动物的威胁方法。本发明结合氨态氮在水中的有毒转化形式，并分别对其含量进行测定，综合评价以氨态氮形式胁迫水生生物后，氮元素在水体中转化的各种有毒化合物的总和，避免以其中某一种单一有毒形式(氨态氮或者亚硝酸氮)评价受污染水体的安全性，造成致毒物质遗漏，或者在后续的环境监测生物标志物筛选及致毒机制研究过程中，生物标志物及致毒机理与环境致毒物质的不一致

饲料中添加壳寡糖对刺参肠壁菌群的影响

为研究饲料中添加壳寡糖对刺参Apostichopus japonicus肠壁菌群的影响,在刺参基础饲料中分别添加0.25%（G1）、0.50%（G2）、0.75%（G3）和1.00%（G4）的壳寡糖,另设对照组（G0）,养殖50 d后采集各组刺参幼参（5.03 g±0.03 g）肠壁样品,并采用高通量测序技术分析刺参肠壁菌群结构特征。结果表明：壳寡糖添加组刺参肠壁的细菌多样性和丰度均高于对照组;各组样品肠壁优势菌门均为变形菌门和厚壁菌门;壳寡糖对刺参肠壁菌群组成产生了明显影响,对照组优势菌属为希瓦氏菌属Shewanella,而壳寡糖添加组希瓦氏菌属的相对比例均下降,对照组芽孢杆菌属Bacillus的相对比例较低,而壳寡糖添加组芽孢杆菌属的相对比例均较高或成为优势菌属;1.00%壳寡糖组各类菌属相对比例均较低,高浓度壳寡糖出现抑制现象。研究表明,饲料中添加壳寡糖可提高刺参肠壁细菌多样性和丰度,明显改善刺参肠壁菌群结构

饲料中添加壳寡糖对刺参肠壁菌群的影响

为研究饲料中添加壳寡糖对刺参Apostichopus japonicus肠壁菌群的影响,在刺参基础饲料中分别添加0.25%（G1）、0.50%（G2）、0.75%（G3）和1.00%（G4）的壳寡糖,另设对照组（G0）,养殖50 d后采集各组刺参幼参（5.03 g±0.03 g）肠壁样品,并采用高通量测序技术分析刺参肠壁菌群结构特征。结果表明：壳寡糖添加组刺参肠壁的细菌多样性和丰度均高于对照组;各组样品肠壁优势菌门均为变形菌门和厚壁菌门;壳寡糖对刺参肠壁菌群组成产生了明显影响,对照组优势菌属为希瓦氏菌属Shewanella,而壳寡糖添加组希瓦氏菌属的相对比例均下降,对照组芽孢杆菌属Bacillus的相对比例较低,而壳寡糖添加组芽孢杆菌属的相对比例均较高或成为优势菌属;1.00%壳寡糖组各类菌属相对比例均较低,高浓度壳寡糖出现抑制现象。研究表明,饲料中添加壳寡糖可提高刺参肠壁细菌多样性和丰度,明显改善刺参肠壁菌群结构