全文获取类型
收费全文 | 32283篇 |
免费 | 836篇 |
国内免费 | 133篇 |
专业分类
化学 | 19946篇 |
晶体学 | 206篇 |
力学 | 856篇 |
综合类 | 9篇 |
数学 | 4347篇 |
物理学 | 7888篇 |
出版年
2023年 | 181篇 |
2022年 | 518篇 |
2021年 | 812篇 |
2020年 | 589篇 |
2019年 | 543篇 |
2018年 | 594篇 |
2017年 | 525篇 |
2016年 | 932篇 |
2015年 | 740篇 |
2014年 | 907篇 |
2013年 | 1441篇 |
2012年 | 1770篇 |
2011年 | 1994篇 |
2010年 | 1177篇 |
2009年 | 1040篇 |
2008年 | 1667篇 |
2007年 | 1616篇 |
2006年 | 1470篇 |
2005年 | 1801篇 |
2004年 | 1792篇 |
2003年 | 1266篇 |
2002年 | 888篇 |
2001年 | 693篇 |
2000年 | 617篇 |
1999年 | 390篇 |
1998年 | 341篇 |
1997年 | 332篇 |
1996年 | 410篇 |
1995年 | 352篇 |
1994年 | 339篇 |
1993年 | 364篇 |
1992年 | 351篇 |
1991年 | 294篇 |
1990年 | 240篇 |
1989年 | 235篇 |
1988年 | 202篇 |
1987年 | 199篇 |
1986年 | 201篇 |
1985年 | 269篇 |
1984年 | 235篇 |
1983年 | 200篇 |
1982年 | 215篇 |
1981年 | 204篇 |
1980年 | 189篇 |
1979年 | 162篇 |
1978年 | 182篇 |
1977年 | 147篇 |
1976年 | 143篇 |
1974年 | 136篇 |
1973年 | 126篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
The Effect of the Spacer of Bis(biurea) Ligands on the Structure of A2L3‐type (A=anion) Phosphate Complexes
下载免费PDF全文
![点击此处可从《Chemistry (Weinheim an der Bergstrasse, Germany)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Prof. Biao Wu Dr. Shaoguang Li Prof. Yibo Lei Prof. Huaiming Hu Dr. Nader de Sousa Amadeu Prof. Dr. Christoph Janiak Dr. Jennifer S. Mathieson Dr. De‐Liang Long Prof. Leroy Cronin Prof. Xiao‐Juan Yang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(6):2588-2593
By tuning the length and rigidity of the spacer of bis(biurea) ligands L, three structural motifs of the A2L3 complexes (A represents anion, here orthophosphate PO43?), namely helicate, mesocate, and mono‐bridged motif, have been assembled by coordination of the ligand to phosphate anion. Crystal structure analysis indicated that in the three complexes, each of the phosphate ions is coordinated by twelve hydrogen bonds from six surrounding urea groups. The anion coordination properties in solution have also been studied. The results further demonstrate the coordination behavior of phosphate ion, which shows strong tendency for coordination saturation and geometrical preference, thus allowing for the assembly of novel anion coordination‐based structures as in transition‐metal complexes. 相似文献
12.
Mariia Svyntkivska Tomasz Makowski Ewa Piorkowska Marek Brzezinski Agata Herc Anna Kowalewska 《Molecules (Basel, Switzerland)》2021,26(5)
Electrospun nonwovens of poly(L-lactide) (PLLA) modified with multiwall carbon nanotubes (MWCNT) and linear ladder-like poly(silsesquioxane) with methoxycarbonyl side groups (LPSQ-COOMe) were obtained. MWCNT and LPSQ-COOMe were added to the polymer solution before the electrospinning. In addition, nonwovens of PLLA grafted to modified MWCNT were electrospun. All modified nonwovens exhibited higher tensile strength than the neat PLA nonwoven. The addition of 10 wt.% of LPSQ-COOMe and 0.1 wt.% of MWCNT to PLLA increased the tensile strength of the nonwovens 2.4 times, improving also the elongation at the maximum stress. 相似文献
13.
Functional Binding Surface of a β‐Hairpin VEGF Receptor Targeting Peptide Determined by NMR Spectroscopy in Living Cells
下载免费PDF全文
![点击此处可从《Chemistry (Weinheim an der Bergstrasse, Germany)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Dr. Donatella Diana Anna Russomanno Dr. Lucia De Rosa Dr. Rossella Di Stasi Dr. Domenica Capasso Dr. Sonia Di Gaetano Dr. Alessandra Romanelli Dr. Luigi Russo Dr. Luca D. D'Andrea Prof. Roberto Fattorusso 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(1):91-95
In this study, the functional interaction of HPLW peptide with VEGFR2 (Vascular Endothelial Growth Factor Receptor 2) was determined by using fast 15N‐edited NMR spectroscopic experiments. To this aim, 15N uniformly labelled HPLW has been added to Porcine Aortic Endothelial Cells. The acquisition of isotope‐edited NMR spectroscopic experiments, including 15N relaxation measurements, allowed a precise characterization of the in‐cell HPLW epitope recognized by VEGFR2. 相似文献
14.
15.
16.
Active anodes, especially those consisting of metal mixed oxides (MMOs) containing Ru and/or Ir oxides, have been applied in the treatment of wastewater, especially when chloride ions are present. Their characteristics continuously drive the study of applications of these materials, be they in the degradation of different organic molecules, the preparation of new electrode materials and in the association of various processes to increase pollutant removal. Thus, this brief review aims to present some of the recent advances in the application of active anode materials in environmental electrochemistry. Focussing on the 2018–2020 period, it is possible to note many applied studies, using commercially available materials, covering a wide range of target pollutants. Still other studies aim to modify the catalyst surfaces to increase the mineralization capacity, and the use of these anodes in the production of free chlorine species to mediate indirect organic reduction is observed. 相似文献
17.
Numerous biological processes are connected with the efficient electron transfer reactions in proteins and peptides. In this review, we discuss briefly the relevance and current challenges associated with the voltammetric analysis of peptides and proteins with and without a metal redox center. Special attention is paid to the integration of electrochemical methods with new nanomaterials which offers amplification of multiplexing capabilities for simultaneous and very sensitive examination of various proteins. After critically discussing the most interesting approaches in the proteins/peptides voltammetric analysis reported so far, for the single or multiplexed examination of such biomolecules with demonstrated applicability in the real-sample analysis, existing challenges still need to be addressed and future directions in this field will be pointed out. 相似文献
18.
Application of TiO2-nanotubes/PbO2 as an anode for the electrochemical elimination of Acid Red 1 dye
Santos José Eudes L. de Moura Dayanne Chianca da Silva Djalma Ribeiro Panizza Marco Martínez-Huitle Carlos A. 《Journal of Solid State Electrochemistry》2019,23(2):351-360
Journal of Solid State Electrochemistry - In this study, galvanostatic electrolysis, through the use of the platinum supported on Ti (Ti/Pt) and Ti/TiO2-nanotubes/PbO2 anodes, was conducted in an... 相似文献
19.
It is known that under resonance conditions, a group of strongly interacting bosonic atoms, trapped in a double-well potential, mimics a single particle, performing Rabi oscillations between the wells. By implication, all atoms need to tunnel at roughly the same time, even though the Bose–Hubbard Hamiltonian accounts only for one-atom-at-a-time transfers. The mechanism of this collective behavior is analyzed, the Rabi frequencies in the process are evaluated, and the limitation of this simple picture is discussed. In particular, it is shown that the small rapid oscillations superimposed on the slow Rabi cycle result from splitting the transferred cluster at the sudden onset of tunnelling, and disappear if tunnelling is turned on gradually. 相似文献
20.
Vieira Renata Leia Demario Gaglieri Caroline de Oliveira Cristina Soltovski Ferreira Laura Teófilo Schnitzler Egon Bannach Gilbert 《Journal of Thermal Analysis and Calorimetry》2021,144(3):689-697
Journal of Thermal Analysis and Calorimetry - Buckwheat starch is an alternative source to supply the high global demand for starch. The properties of starch can be modified through chemical and... 相似文献