全文获取类型
收费全文 | 405篇 |
免费 | 67篇 |
国内免费 | 106篇 |
专业分类
测绘学 | 35篇 |
大气科学 | 164篇 |
地球物理 | 65篇 |
地质学 | 195篇 |
海洋学 | 56篇 |
天文学 | 3篇 |
综合类 | 26篇 |
自然地理 | 34篇 |
出版年
2023年 | 6篇 |
2022年 | 15篇 |
2021年 | 18篇 |
2020年 | 9篇 |
2019年 | 15篇 |
2018年 | 18篇 |
2017年 | 16篇 |
2016年 | 16篇 |
2015年 | 21篇 |
2014年 | 22篇 |
2013年 | 20篇 |
2012年 | 24篇 |
2011年 | 20篇 |
2010年 | 21篇 |
2009年 | 20篇 |
2008年 | 18篇 |
2007年 | 22篇 |
2006年 | 14篇 |
2005年 | 14篇 |
2004年 | 8篇 |
2003年 | 16篇 |
2002年 | 13篇 |
2001年 | 11篇 |
2000年 | 24篇 |
1999年 | 12篇 |
1998年 | 14篇 |
1997年 | 18篇 |
1996年 | 17篇 |
1995年 | 18篇 |
1994年 | 16篇 |
1993年 | 12篇 |
1992年 | 17篇 |
1991年 | 9篇 |
1990年 | 8篇 |
1989年 | 13篇 |
1988年 | 6篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1985年 | 2篇 |
1984年 | 7篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1981年 | 1篇 |
排序方式: 共有578条查询结果,搜索用时 15 毫秒
471.
472.
473.
474.
中国地区云对地气系统长波射出辐射(OLR)强迫的气候研究 总被引:1,自引:0,他引:1
本文利用地球辐射平衡试验(ERBE)和国际卫星去气候计划(ISCCP)提供的地气系统长波射出辐射(OLR)和云量资料,计算半讲座了我国各季和年平均去量对地气系统OLR的强迫及其所产生的温室效应,结果表明:我国各季的OLR云强迫与总云量,高云量都有较好的相关,且季节变化明显;OLR云强迫和云温室效应的地理分布受云量和云状的影响较大,它们的年变化一般呈弱双峰型,峰值在春,夏季出现。 相似文献
475.
By using the climatological calculating method for each component of slope surface net radiation proposedby the authors,calculations and analyses are done of the distribution features of slope net radiation in Chinawith emphasis on the discussion of variations of slope net radiation in typical stations and sites with slope direc-tion,slope,latitude and season.The distribution features of net radiation on the north and south slopes are,for the first time,mapped and discussed,revealing the great difference on the national basis,and thus acquiringa new interesting result that the negative-value area of winter net radiation on the north slope(20°)can reachYunnan and Guizhou Provinces and middle and upper reaches of the Changjiang River. 相似文献
476.
本文根据1979年5~8月青藏高原气象科学实验资料,研究了利用卡斯特洛夫公式计算青藏高原晴天太阳直接辐射的有关问题。首先从原始资料中挑选出晴天太阳直接辐射并计算其日平均辐照度,然后以此为标准,利用迭代法反求可能太阳直接辐射日平均辐照度理论公式中的系数C,建立该系数与平均水汽压的经验公式,再利用经验式反演晴天太阳直接辐射。本文还比较了由乌克兰英采夫法确定的可能太阳直接辐射与实际晴天太阳直接辐射的差异,证实前者要比后者偏大,其偏离程度随站点拔海高度增加而缩小。文中最后讨论了青藏高原晴天太阳直接辐射日平均辐照度的地理分布,并分析了其随拔海高度的变化。 相似文献
477.
An established climatic calculation scheme for estimating the components of surface radiation budget is conducted at 223 stations throughout the country.The spatial patterns of net radiation (NR) and its components suggest that the high-value belt is steadily situated over the Yarlung Zangbo Basin in the southern Qinghai-Xizang Plateau and over the eastern Inner Mongolian Plateau,with the low-value belt over Sichuan-Guizhou mountainous temain.The pattern changes a little with the transition of seasons.Temporally,the NR's annual changes,especially its maximizing month,are closely related to the coming of rainy season.The relative computation emor is 2.7% for global radiation (GR).4.0% for surface albedo(SA),9.4% for effective radiation (ER),and 8.9% for NR. 相似文献
478.
Detailed analysis is made of anisotropy of slope scattered radiation (SSR) in terms of the data obtained by a pyranometer mounted on a theodolite,indicating the change of SSR as a function of orientation and slope.And also reviewed are the models for SSR calculation developed by earlier researchers through the tests with the data.On this basis a new model for SSR flux density is proposed which is of higher applicability and has advantage over the analogues abroad both in physical implication and accuracy of the calculations. 相似文献
479.
In this paper we consider temperature (% MathType!MTEF!2!1!+-% feaafeart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGafuiMdeLbae% baaaa!377B!\[\bar \Theta \]) and specific humidity (% MathType!MTEF!2!1!+-% feaafeart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmyuayaara% aaaa!36DA!\[\bar Q\]) fields in the lower part of the planetary boundary layer and present a method for calculating the way these variables and their fluxes vary over changes in available surface moisture expressed as a surface resistance. Near the surface, the turbulence is close to equilibrium and an eddy diffusivity model enables the changes in (% MathType!MTEF!2!1!+-% feaafeart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGafuiMdeLbae% baaaa!377B!\[\bar \Theta \]), % MathType!MTEF!2!1!+-% feaafeart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmyuayaara% aaaa!36DA!\[\bar Q\], sensible heat flux (% MathType!MTEF!2!1!+-% feaafeart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmOrayaara% WaaSbaaSqaaiaadIeaaeqaaaaa!37C8!\[\bar F_H \]), and latent heat flux (% MathType!MTEF!2!1!+-% feaafeart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmOrayaara% WaaSbaaSqaaiaadweaaeqaaaaa!37C5!\[\bar F_E \]) to be determined in terms of the assumed mean wind, turbulence profiles and upwind profiles of temperature and humidity. An important advantage of this method is that it is possible to consider arbitrary changes in surface properties. 相似文献
480.