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101.
利用1∶200 000地球化学数据,从整个成矿地球化学环境的角度出发,最大限度地开发、挖掘三十九种化学元素中每个元素以及元素组合所蕴含的矿化信息,为成矿远景区预测提供更加翔实的地球化学依据,是地球化学工作者的研究任务之一。MAPGIS功能强大,其地图库管理模块为多幅1∶200 000地球化学异常图的拼接提供了技术支持。这里论述了1∶200 000地球化学数据的特征和MAPGIS的地图库管理的功能,并记述了在实际工作中应用MAPGIS的地图库管理对多幅1∶200 000地球化学异常图的拼接,实现了对1∶200 000地球化学数据的另一种应用方式。 相似文献
102.
YAN Hao-wen LI Zhi-lin AI Ting-hua 《中国地理科学(英文版)》2006,16(2):165-170
1INTRODUCTION Map generalization may be defined as a procedure that generatessmallerscalemapsfromlargerscaleonesusing variousappropriateoperations (e.g.selection,combina- tion, displacement, simplification, etc.) under definite conditions (includingmap scale, purpose, etc.). The au- tomation of the generalization process has been a dream of cartographers for decades. For it is an indispensable wayto construct map databases from large-scale maps to small-scale ones, which can decrease repet… 相似文献
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Development of a national VNIR soil-spectral library for soil classification and prediction of organic matter concentrations 总被引:4,自引:0,他引:4
SHI Zhou WANG QianLong PENG Jie JI WenJun LIU HuanJun LI Xi Raphael A VISCARRA ROSSEL 《中国科学:地球科学(英文版)》2014,57(7):1671-1680
Soil visible-near infrared diffuse reflectance spectroscopy(vis-NIR DRS)has become an important area of research in the fields of remote and proximal soil sensing.The technique is considered to be particularly useful for acquiring data for soil digital mapping,precision agriculture and soil survey.In this study,1581 soil samples were collected from 14 provinces in China,including Tibet,Xinjiang,Heilongjiang,and Hainan.The samples represent 16 soil groups of the Genetic Soil Classification of China.After air-drying and sieving,the diffuse reflectance spectra of the samples were measured under laboratory conditions in the range between 350 and 2500 nm using a portable vis-NIR spectrometer.All the soil spectra were smoothed using the Savitzky-Golay method with first derivatives before performing multivariate data analyses.The spectra were compressed using principal components analysis and the fuzzy k-means method was used to calculate the optimal soil spectral classification.The scores of the principal component analyses were classified into five clusters that describe the mineral and organic composition of the soils.The results on the classification of the spectra are comparable to the results of other similar research.Spectroscopic predictions of soil organic matter concentrations used a combination of the soil spectral classification with multivariate calibration using partial least squares regression(PLSR).This combination significantly improved the predictions of soil organic matter(R2=0.899;RPD=3.158)compared with using PLSR alone(R2=0.697;RPD=1.817). 相似文献
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A muscle cDNA library of Chinese shrimp (Fenneropenaeus chinensis) was constructed with the SMART™ cDNA Library Construction Kit. The titer of optimal primary library was 7.7×105 pfu mL−1 and that of the amplified library was 3.0×109 pfu mL−1. The percentages of the recombinant clones of primary and amplified libraries were over 98%. The insert sizes were longer
than 400 bp with an average of 1000 bp. A positive clone containing a 794 bp insert was sequenced and identified encoding
fast skeletal troponin I gene. This library provided a useful resource for the functional genomic research of F. chinensis. 相似文献
108.
A muscle cDNA library of Chinese shrimp (Fenneropenaeus chinensis) was constructed with the SMARTTM cDNA Li- brary Construction Kit. The titer of optimal primary library was 7.7×105 pfu mL-1 and that of the amplified library was 3.0×109 pfu mL-1. The percentages of the recombinant clones of primary and amplified libraries were over 98%. The insert sizes were longer than 400 bp with an average of 1000 bp. A positive clone containing a 794 bp insert was sequenced and identified encoding fast skeletal troponin Ⅰ gene. This library provided a useful resource for the functional genomic research ofE chinensis. 相似文献
109.
“物化探技术方法库”是“中国地质调查技术方法信息网”的有机组成部分。通过研究,将物探方法归纳为重力、磁法、电法、地震、放射性和地温6大类25种方法,将化探方法归纳为沉积物、土壤、岩石、气体、水、生物和其他等7大类16种方法。对每种技术方法均作了概要性的简介;经筛选,编制入库物化探技术方法、仪器设备、软件及应用实例等信息条目208条,初步充实了物化探技术方法库的内容,为服务平台物化探方法技术库运行提供了基本条件。 相似文献
110.
雨生红球藻cDNA表达文库的构建与初步分析 总被引:1,自引:0,他引:1
为了筛选雨生红球藻虾青素合成过程中的关键酶基因的反式调节因子基因,以雨生红球藻的绿细胞为材料,提取了高质量的总RNA,并分离纯化了mRNA,经过反转录后的得到cDNA,构建了以λ-ZAPExpress为载体的表达型cDNA文库。经检测,所构建的文库的滴度为5.1×105,重组率为100%。用PCR方法对文库的质量进行了鉴定,文库的平均插入片断的大小为1.7kb。雨生红球藻cDNA表达文库的构建为研究虾青素的代谢工程奠定了基础。 相似文献