建鲤基因组DNA的RAPD分析     

董在杰  朱健  袁新华  王建新  姜焱 《广东海洋大学学报》2002,22(1):3-6

用 1 5个随机引物对建鲤基因组DNA进行RAPD分析 ,结果显示 ,建鲤群体内的遗传相似系数为 0 91 81± 0 0 73 8,多态位点比例为 0 41 67,平均杂合度为 0 1 884。表明建鲤种质较纯 ,群体内的遗传变异程度较小。建鲤优良性状产生的分子学基础是等位基因的杂合程度较高  相似文献   

穆珠朗玛峰地区土壤中稀土元素的含量和分布     

章申  孙景信 《地理研究》1990,9(2):58-66

本文论述了珠穆朗玛峯地区土壤中稀土元素的含量,以及它们在土壤中的分布模式,并发现土壤中稀土元素的含量水平在很大程度上受土壤母质的制约。  相似文献   

双极化天气雷达方程     

董豹  王贤勤 《成都信息工程学院学报》1996,(3)

在回转椭球状降水粒子的假设下求出了降水粒子的散射截面，并且考虑了粒子轴线铅垂和随机取向两种重要的典型情况；推导了双极化雷达的回波方程以及降雨量公式。该方程除包含降水粒子的信息外，关于雷达与降水粒子间的几何关系都以雷达天线仰角及雷达与降水粒子间的距离表示，同时还考虑了地球的球面效应和大气折射效应。由于采用了并矢方法，使推导简捷明了  相似文献   

Precipitation patterns in flood season over China associated with the El Niño/Southern Osciliation     

Budong Qian 《中国地理科学(英文版)》1997,7(3):220-228

The precipitation patterns in flood season over China associated with the El Niño/Southern Oscillation (ENSO) are investigated, especially in the eastern China, using the rather long period rainfall data in this century. The results show that there were remarkable differences between the precipitation patterns in flood seasons of ENSO warm phase (El Niño year) and cold phase (La Niña year), as well as between the patterns in El Niño years and their following years. The most parts of China received below normal rainfall in flood season of the onset years of El Niño events, but the coastal area of Southeast China received above normal amounts. Comparatively, the most parts of China received above normal rainfall in flood season of the following years of El Niño events, but the eastern part of the reaches among the Huanghe (Yellow) River, the Huaihe River and the Haihe River, and the Northeast China received less. During ENSO cold phase, the reaches of the Changjiang (Yangtze) River and the North China received more amounts than normal rainfall in flood season of the onset years of La Niña events, and the other regions of China received less. In the following years of La Niña events, the coastal area of the Southeast China, the most part of the Northeast China and the regions between the Huanghe River and the Huaihe River received more precipitation during flood seasons, but the other parts received below normal precipitation.  相似文献   

Regionalization for large area crop estimates by remote sensing     

Qian Huaisui 《中国地理科学(英文版)》1997,8(3):204-211

The crop estimates by remote sensing, developing quickly in recent decades, is a up-to-date technique. Regionalization for large area crop estimates by remote sensing, a special applied regionalization, is the foundation of crop estimates in a large area by remote sensing. According to the actual demands of wheat yield estimation by remote sensing and wheat agroclimatic demarcation of China, this paper first puts forward some principles upheld in this regionalization and analyses its main bases. Secondly, it works out the classificatory schemes about the optimum temporal for estimating wheat yield by remote sensing, information sources of space remote sensing and landuse structure in China. Finally, According to the regionalization indices, this study divides the wheat plantable region of China into 14 regions of crop yield estimates and 31 subregions of crop yield estimates.  相似文献   

STUDY ON THE INTERACTION BETWEEN NDVI PROFILE AND THE GROWING STATUS OF CROPS   总被引：5，自引：1，他引：4  

JIANGDong WANGNai-bin YANGXIao-huan WANGJi-hua 《中国地理科学(英文版)》2003,13(1):62-65

Daily and ten-day Normalized Difference Vegetation Index(NDVI) of crops were retrieved from meteorological statellite NOAA AVHRR images ,The temporal variations of the NDVI were analyzed during the whole growing season,and thus the principle of the interaction between NDIV profile and the growing status of crops was discussed,As a case in point,the relationship between integral NDVI and winter wheat yield of Henan Province in 1999 had been analyzed.By putting integral NDVI values of 60 sample counties into the winter wheat yield-integral NDVI coordination,scattering map was plotted. It demonstrated that integral NDVI had a close relation with winter wheat yield.These relation could be described with linear,cubic polynomial ,and exponential regression,and the cubic polynomial regression was the best way,In general ,NDVI reflects growing status of green vegetation ,so crop monitoring and crop yield estimation could be realized by using remote sensing technique on the basis of time serial NDVI data together with agriculture calendars.  相似文献   

N_（263）浸渍树脂分离─富集Pb（Ⅱ）的研究及其应用     

丛玉梅  钱程 《国土资源》1995,(1)

以Ｎ＿（２６３）浸渍在ＤＡ＿（２０１）大孔吸附树脂上制得了Ｎ＿（２６３）浸渍树脂，测定了静态时树脂Ｐｂ（Ⅱ）的吸附容量。通过柱层析法，试验了酸度，流速和干扰离子等因素对Ｎ＿（２６３）浸渍树脂吸附和洗脱Ｐｂ的影响。建立了Ｎ＿（２６３）浸渍树脂分离─富集后衔接原子吸收和比色法测定Ｐｂ（Ⅱ）的方法，测定了地质样品中Ｐｂ（Ⅱ），测试结果理想。  相似文献   

马面卵巢在不同贮藏温度下磷脂成分的变化     

杨文鸽  钱云霞  洪鹏志 《广东海洋大学学报》2001,21(1):35-38

在20℃、4℃、-10℃、-20℃四种温度下贮藏马面卵巢，对其中磷脂含量的变化进行了测定，并利用薄层层析分析测定了不同温度下贮存3d后马面卵巢中磷脂各组分的相对百分比。结果表明马面卵巢中磷脂的损失率随贮藏温度的上升而增加；在不同温度下贮藏3d，磷脂各组分的相对百分比都发生了变化；随贮藏温度的升高磷脂酰胆碱的降解速度大大加快，所占的百分比快速下降，而溶血磷脂酰胆碱的比例有不同程度的增加。相对而言，-20℃下贮藏数天，磷脂的含量及组分的变化较小。  相似文献   

FITS、BMP和SCR图象格式及相互转换   总被引：1，自引：0，他引：1  

季凯帆  曹文达  宋谦 《天文研究与技术》1996,(2)

本文详细介绍图象的ＦＩＴＳ格式、ＢＭＰ格式和ＳＣＲ格式。ＦＩＴＳ格式已经是天文界的通用格式，几乎所有的天文软件包都支持这一格式，而ＢＭＰ格式在ＰＣ计算机上有广泛的运用，有大量ＰＣ软件支持ＢＭＰ图象的显示，处理和打印。云南天文台的ＳＣＲ格式是ＰＣ机采集ＣＣＤ图象所使用的格式。实现这三种格式的相互转换，就可以自由的将ＣＣＤ图象在ＰＣ机和工作站上进行各种处理。转换的包括图象头和图象数据的转换，其关键在于交换数据的高低字节。  相似文献   

鄂尔多斯高原晚更新世以来的古冰缘现象及其气候地层学意义   总被引：18，自引：1，他引：17  

董光荣  高尚玉  李保生  吴正 《地理研究》1985,4(1):1-13

本文概述了鄂尔多斯高第三系至全新统地层中融冻(衤习)皱和沙(土)楔两类古冰縁现象的分布与形态特征,探索了它们的成因以及同所在地层和上覆风成沙或黄土的关系,並对古冰縁现象的气候地层学意义作了讨论。  相似文献