全文获取类型
收费全文 | 24500篇 |
免费 | 77篇 |
国内免费 | 39篇 |
专业分类
化学 | 10530篇 |
晶体学 | 408篇 |
力学 | 951篇 |
综合类 | 11篇 |
数学 | 3536篇 |
物理学 | 9180篇 |
出版年
2023年 | 15篇 |
2022年 | 179篇 |
2021年 | 371篇 |
2020年 | 372篇 |
2019年 | 552篇 |
2018年 | 1009篇 |
2017年 | 1118篇 |
2016年 | 1339篇 |
2015年 | 547篇 |
2014年 | 1125篇 |
2013年 | 1694篇 |
2012年 | 1531篇 |
2011年 | 1612篇 |
2010年 | 1803篇 |
2009年 | 1746篇 |
2008年 | 1741篇 |
2007年 | 1662篇 |
2006年 | 1442篇 |
2005年 | 907篇 |
2004年 | 647篇 |
2003年 | 352篇 |
2002年 | 345篇 |
2001年 | 318篇 |
2000年 | 633篇 |
1999年 | 357篇 |
1998年 | 450篇 |
1997年 | 425篇 |
1996年 | 110篇 |
1995年 | 34篇 |
1994年 | 30篇 |
1993年 | 4篇 |
1992年 | 13篇 |
1991年 | 11篇 |
1990年 | 14篇 |
1989年 | 6篇 |
1988年 | 7篇 |
1987年 | 10篇 |
1986年 | 6篇 |
1984年 | 6篇 |
1983年 | 8篇 |
1982年 | 6篇 |
1981年 | 5篇 |
1980年 | 4篇 |
1978年 | 3篇 |
1977年 | 4篇 |
1974年 | 5篇 |
1972年 | 2篇 |
1971年 | 5篇 |
1968年 | 10篇 |
1875年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Differential Equations - For a spectrally controllable linear autonomous system with incommensurable delays, we construct a dynamic state feedback in the form of a differential-difference... 相似文献
2.
JETP Letters - Extraordinary multiparticle effects in quantizing magnetic fields that are manifested in strongly interacting two-dimensional electron systems in MgZnO/ZnO heterostructures have been... 相似文献
3.
Kuz’mina L. G. Navasardyan M. A. Kalle P. Bezzubov S. I. 《Crystallography Reports》2021,66(3):420-423
Crystallography Reports - The crystal and molecular structures of Cl–C6H4–O–C16H33 (I) have been studied, and its differential scanning calorimetry (DSC) study is performed.... 相似文献
4.
Daulbaev O. Isaenko L. I. Bogdzel’ A. A. Lobanov S. I. Krinitsyn P. G. Milkov V. M. Belushkin A. V. 《Crystallography Reports》2022,67(3):464-469
Crystallography Reports - Two LiInSe2 single crystals, grown under different conditions, have been studied. Characteristics of these crystals for neutron detection have been compared using... 相似文献
5.
Kang Il Yoo Ji Yeong Jeon Su Jeong Ryu Giri Nam Hyewon Youn Eun Young Choi 《Experimental & molecular medicine》2015,47(2):e140
In allogeneic transplantation, including the B6 anti-BALB.B settings, H60 and H4 are two representative dominant minor histocompatibility antigens that induce strong CD8 T-cell responses. With different distribution patterns, H60 expression is restricted to hematopoietic cells, whereas H4 is ubiquitously expressed. H60-specific CD8 T-cell response has been known to be dominant in most cases of B6 anti-BALB.B allo-responses, except in the case of skin transplantation. To understand the mechanism underlying the subdominance of H60 during allogeneic skin transplantation, we investigated the dynamics of the H60-specific CD8 T cells in B6 mice transplanted with allogeneic BALB.B tail skin. Unexpectedly, longitudinal bioluminescence imaging and flow cytometric analyses revealed that H60-specific CD8 T cells were not always subdominant to H4-specific cells but instead showed a brief dominance before the H4 response became predominant. H60-specific CD8 T cells could expand in the draining lymph node and migrate to the BALB.B allografts, indicating their active participation in the anti-BALB.B allo-response. Enhancing the frequencies of H60-reactive CD8 T cells prior to skin transplantation reversed the immune hierarchy between H60 and H4. Additionally, H60 became predominant when antigen presentation was limited to the direct pathway. However, when antigen presentation was restricted to the indirect pathway, the expansion of H60-specific CD8 T cells was limited, whereas H4-specific CD8 T cells expanded significantly, suggesting that the temporary immunodominance and eventual subdominance of H60 could be due to their reliance on the direct antigen presentation pathway. These results enhance our understanding of the immunodominance phenomenon following allogeneic tissue transplantation. 相似文献
6.
7.
8.
9.
New Effects in the Poly-N-Vinylcaprolactam/Titanium(IV) Oxides Nanocomposite System and Their Nature
Nanocomposites based on poly-N-vinylcaprolactam (PVC), characterized by different drying temperatures of aqueous PVC solution at 25°С (PVC25) and 40°С (PVC40), with titanium(IV) oxide nanoparticles (TONs) (η-phase (TP: TiO2 – x · mH2O) with a superstructure to the anatase structure and ordered solid solution with partial replacement of oxygen atoms in the η-phase with peroxo group O 2 2– (PP: TiO x (O2)2 – x · nH2O)) have been obtained for the first time and characterized by X-ray diffraction and IR spectroscopy. It is found that a common feature of TP/PVC and PP/PVC obtained by dry mixing and grinding is the decrease in the number of water molecules for TP and PP in the interlayer space of the structure and their attachment to the PVC amide groups; the differences are related to the specificity of PVC behavior in these systems: mechanodestruction of PVC in PP/PVC40 and different numbers of water molecules in PVC25 and PVC40. 相似文献
10.
V. A. Bespalov V. M. Glazov E. A. Il’ichev Yu. A. Klimov S. V. Kuklev A. E. Kuleshov R. M. Nabiev G. N. Petrukhin B. G. Potapov G. S. Rychkov D. S. Sokolov V. V. Fandeev E. A. Fetisov S. S. Yakushov 《Technical Physics》2015,60(4):553-560
The results of investigation of optical image detectors designed for the largest problem, near-VUV, range of the spectrum are presented. The possibility of using a dual-stage image detection system to appreciably lower the sensitivity threshold and make computer data processing feasible is considered. The integration of a UV module into a wideband image detector is studied. 相似文献