全文获取类型
收费全文 | 3782篇 |
免费 | 121篇 |
出版年
2020年 | 42篇 |
2019年 | 49篇 |
2018年 | 80篇 |
2017年 | 80篇 |
2016年 | 106篇 |
2015年 | 74篇 |
2014年 | 67篇 |
2013年 | 1068篇 |
2012年 | 97篇 |
2011年 | 127篇 |
2010年 | 108篇 |
2009年 | 88篇 |
2008年 | 94篇 |
2007年 | 64篇 |
2006年 | 63篇 |
2005年 | 62篇 |
2004年 | 55篇 |
2003年 | 30篇 |
2002年 | 38篇 |
2001年 | 60篇 |
2000年 | 49篇 |
1999年 | 56篇 |
1998年 | 38篇 |
1997年 | 43篇 |
1996年 | 38篇 |
1995年 | 30篇 |
1994年 | 37篇 |
1993年 | 42篇 |
1992年 | 44篇 |
1991年 | 35篇 |
1990年 | 29篇 |
1989年 | 36篇 |
1988年 | 34篇 |
1987年 | 45篇 |
1986年 | 30篇 |
1985年 | 48篇 |
1984年 | 37篇 |
1983年 | 65篇 |
1982年 | 48篇 |
1981年 | 55篇 |
1980年 | 54篇 |
1979年 | 38篇 |
1978年 | 40篇 |
1977年 | 58篇 |
1976年 | 42篇 |
1975年 | 44篇 |
1974年 | 31篇 |
1973年 | 29篇 |
1972年 | 26篇 |
1971年 | 33篇 |
排序方式: 共有3903条查询结果,搜索用时 15 毫秒
171.
172.
173.
174.
175.
The inorganic inclusions contained in amber fragments from Baltic regions and from the Simeto basin (Sicily, Italy) have been analyzed. The study, performed with the aid of a scanning electron microscope, shows specimen similarities and differences that are dependent on the place of origin. 相似文献
176.
S. G. E. BOWMAN 《Archaeometry》1975,17(1):129-132
Recent studies on pottery and related materials have shown there to be cases where the degree of supralinearity is dependent on the previous radiation history of the sample. Results are presented of two investigations of this variation with pre-dose: one using pottery, the other using fired feldspars. For these samples no simple form for the variation can be inferred. 相似文献
177.
P. G. MANNING 《Archaeometry》1975,17(2):233-235
It is shown, from comparisons with the optical absorption of minerals, that the black and grey colours of pottery can arise from Fe2+ Fe3+ and Fe2+ Ti4+ charge-transfer (or electron-hopping) processes, the cations being located at the centres of adjacent edge-sharing octahedra. 相似文献
178.
179.
180.
Richard G. Davies 《Journal of Medieval History》1975,1(4):329-362
The years 1396–1399 were critical ones in terms of European and English politics alike and, concomitantly, in the course of the Great Schism of the West. England's attitude to the Schism at this time has hitherto been considered primarily from a presupposition of Richard II's own attitude and authority and as an aspect of European politics. An examination of the direct relationship between Richard II and both the Urbanist papacy and the English Church raises some doubts about the extent of his authority in ecclesiastical affairs both before and after his emphatic reassertion of his prerogative in 1397. Particular consideration is given to his personal view of his proper interest. A discussion of the effect of royal policy on the English Church, especially in respect of the episcopate, suggests that, both in practice and in theory, his influence, whilst strong, rested on co-operation as much as coercion, and the nature of the Anglo-papal concordat of November 1398 is reconsidered in this light. It is suggested that greater stress should be laid on the spiritual considerations which weighed with all parties at the time alongside those of a more familiar secular kind. 相似文献