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81.
黄玉锦  阮诗昆 《江苏地质》2018,42(3):440-445
福建紫金山铜矿床属高硫浅成中低温热液矿床,矿石中主要含铜矿物为蓝辉铜矿、铜蓝和硫砷铜矿等,且铜矿物与黄铁矿密切共生。由于铜矿石中硫含量较高,导致铜精矿中硫含量超标,w(S)/w(Cu)比值为2.0~2.1,远高于冶炼要求的1.15~1.20,影响其经济价值。使用X射线荧光(XRF)光谱分析对紫金山铜矿中S元素的分布进行数字化研究,查明硫的空间分布规律和赋存状态,划分铜矿石类型,为紫金山铜矿今后的采选工作提供参考。  相似文献   
82.
Phosphorus (P) in soils has an important influence on the development and productivity of wetland. The objective of this study was to investigate the distribution, bioavailability and seasonal variations of inorganic phosphorus (IP) in soils of Yeyahu Wetland. The results showed that the concentration of Ca-bound P (Ca-P) remained the main occurrence in all IP fractions despite the season, at the same time the Al-bound P (Al-P) was always the lowest IP fraction despite the season. Al-P and Fe-bound P (Fe-P) concentration were all reached the highest value in May and the lowest in November, which was opposite to the occluded P (Oc-P) fraction. The notable higher Oc-P concentration in November observed in this study was probably due to the decomposition of plants and the subsequently releasing of oxides to soils. Ca-P didn't change much with season variations. Exchangeable P (Ex-P) and Oc-P were all positively correlated with soil moisture content and organic matter content, but Al-P was negatively correlated with these two soil properties. As a stable form, Ca-P was not associated with soil properties. Al-P, Fe-P and Ca-P might contribute to the storage of P in studied wetland with the principle component analysis results. The concentration rank order of the bio-available P in soils was generally as follows: Olsen-P > Algal available P (AAP) > Water soluble P (WSP) > Readily desorbed P (RDP). Olsen-P was positively correlated with Ex-P and Oc-P, and it was thought to be a more suitable indicator for bio-available P in soils.  相似文献   
83.
FY-3A/MERSI数据在山东省农田干旱监测中的应用   总被引:1,自引:0,他引:1  
干旱是影响社会发展和农业生产的主要气象灾害之一。利用中国新一代极轨气象卫星FY-3A上搭载的250 m中分辨率光谱成像仪(MERSI)数据,基于垂直干旱指数(PDI),结合山东省旱情统计数据,建立了适合山东省的PDI干旱指数分级标准,在此基础上对山东省2010~2011年秋冬季的干旱状况进行了监测,并将监测结果与同期的降水、温度和干旱监测资料以及19个国家级农气站的土壤相对湿度资料进行对比分析。结果表明:基于FY-3A/MERSI 250 m分辨率卫星资料计算的PDI能够客观反映山东省旱情的空间分布和动态发展过程。PDI与对应实地观测的10 cm、20 cm土壤相对湿度之间有较好的负相关性,且20 cm的土壤相对湿度较10 cm的土壤相对湿度与PDI的相关关系更稳定。因此,利用FY-3A/MERSI卫星资料监测山东省干旱状况具有可行性,适于在干旱监测业务中推广应用。  相似文献   
84.
To understand the mechanisms underlying the effects of climate variation, especially the effects of water on vegetation, vegetation type and distribution as well as climate data and soil type were used to simulate present vegetation distributions and net primary productivity (NPP) under present and future climate scenarios SRES-A2 and SRES-B2. A natural vegetation NPP model was also applied to calculate future vegetation NPP. The results showed that water played a dominant role not only in the distribution of vegetation, but also in the rate of change in the vegetation area. Analysis of NPP showed that precipitation had more effects on the amount of biome NPP than temperature did. Different effects were observed for the rate of change in NPP. In cases where biomes remain unaltered, the variation in annual precipitation could account for 39% of the variation in NPP. In cases where biomes changed, 45% of NPP was caused by temperature variation. Regarding the variation in transect production, −2.85% resulted from the change in vegetation structure when compared with present NPP, and 7.69% from the climate change under scenario SRES-B2; these values were −7.4 and 19.56%, respectively, under scenario SRES-A2. The results showed water served as a dominant factor controlling the vegetation distributions and NPP. However, temperature became determinant where the biomes changed, impacting the rate of change in vegetation NPP when the climate changed. The results also showed that water would have a positive effect on transect production, and the structure of vegetation had a negative effect under the projected future climate.  相似文献   
85.
The aim of this study was to identify some new factors that may impact the occurrence and distribution of landslides based on light detection and ranging digital elevation model (LiDAR DEM), and to examine whether these factors can apply to distinguish between landslide and non-landslide pixels. Twenty-one landslide influential factors were identified. Thereinto, there were ten novel factors, namely the texture factors of slope and surface roughness, including the contrast (Con), correlation (Cor), angular second moment, entropy, and homogeneity (Hom) textures. Qualitative and quantitative analysis and feature selection method were applied to examine the application of these factors. The analysis results indicate that these factors have certain abilities to distinguish between landslide and non-landslide objects. And the selected optimal factors combination that derived from feature selection method was DEM, slope, Hom_d, Con_s, Cor_s, Hom_s, Con_r, Cor_r, and Hom_r (_d, _s, and _r represent DEM, slope, and surface roughness textures, respectively). In conclusion, the identified landslide influential factors can provide effective information for landslide identification. And the new texture factors of slope and surface roughness could act as important measurements that can improve the precision of landslide inventory mapping, susceptibility mapping, and risk assessment.  相似文献   
86.
传统观点认为从烃源岩中分离出的干酪根是油气生成的母质,但它的处理方式破坏了有机质与矿物的原始赋存状态。为此,选取济阳坳陷埋深280~3 900m烃源岩,提取<2μm的有机黏粒复合体,研究其结构和生烃特征。有机黏粒复合体主要由蒙皂石和伊利石组成,TOC为2.62%~9.78%,经H2O2处理后TOC仍高达1.23%~4.63%,表明烃源岩中有机质主要富集在有机黏粒复合体中。有机黏粒复合体加热到250℃时,在XRD曲线上的衍射峰(d001)在1.3~1.4nm;加热至550℃时,衍射峰(d001)才移至1.0nm处;并且在DTA曲线上350℃附近的放热峰极其稳定,这些特征表明有机质进入到黏土矿物层间域。在PY-GC(热解—色谱)曲线上,烃源岩和有机黏粒复合体都在250~550℃释放C20—C30的有机组分,并在450℃释放量达到峰值。由此可见,烃源岩中的有机黏粒复合体,是烃源岩中有机质富集的主体,具有较好的稳定性,并释放出与原油特征相似的有机组分,表明它是具有巨大潜力的天然的生烃母质。  相似文献   
87.
<正>Objective The Songnen masiff is located to the east of the Central Asian Orogenic Belt.The existence and rather the scale and nature of the Precambrian crystalline basement is controversial.Based on recent study of zircon U-Pb chronology,besides a minor number of Neoproterozoic strata,most of the so-called Precambrian metamorphic rock series,such as the Dongfengshan Group and the Zhangguangcailing Group,were formed in the Mesozoic  相似文献   
88.
上海市崇明岛浅层砂土、粉土分布探讨   总被引:3,自引:4,他引:3  
通过对崇明岛内大量勘探资料的分析研究,本文分析了岛内浅层砂土、粉土的分布特征,并根据岩性及静力触探指 标对其进行详细分类,找出了每类土的典型静力触探曲线,最后探讨了各类土的液化问题。  相似文献   
89.
气象数据宽带通信网的建设为实现全国新一代多普勒天气雷达资料的实时应用提供了支撑。本文介绍了国家气象中心预报业务支持环境(FOSE)下的,基于准实时PUP产品的高频度全国和区域雷达拼图以及单站雷达产品的设计制作方法和业务化流程。作者参与开发的雷达拼图产品制作服务程序充分考虑了业务实际需求,设计灵活,投入使用以来运行稳定。  相似文献   
90.
强天气监测和潜势预报系统   总被引:1,自引:1,他引:1  
该文介绍了国家气象中心的强天气监测和潜势预报系统(NMICAPS短时预报版),该系统是在NMICAPS系统的基础上,为满足国家气象中心的强天气监测和潜势预报业务的需求而开发的。系统采用Linux操作系统平台,在资料检索、数据分析、地理信息应用等几个方面进行了改进,并增加了一些针对强天气潜势预报的功能。该系统操作简便,基本能够满足该项业务的需要。  相似文献   
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