全文获取类型
收费全文 | 1510篇 |
免费 | 47篇 |
国内免费 | 3篇 |
专业分类
化学 | 1026篇 |
晶体学 | 9篇 |
力学 | 53篇 |
数学 | 282篇 |
物理学 | 190篇 |
出版年
2023年 | 7篇 |
2022年 | 7篇 |
2021年 | 17篇 |
2020年 | 18篇 |
2019年 | 15篇 |
2018年 | 17篇 |
2017年 | 15篇 |
2016年 | 34篇 |
2015年 | 37篇 |
2014年 | 41篇 |
2013年 | 82篇 |
2012年 | 126篇 |
2011年 | 112篇 |
2010年 | 89篇 |
2009年 | 83篇 |
2008年 | 105篇 |
2007年 | 113篇 |
2006年 | 96篇 |
2005年 | 90篇 |
2004年 | 78篇 |
2003年 | 55篇 |
2002年 | 53篇 |
2001年 | 12篇 |
2000年 | 10篇 |
1999年 | 16篇 |
1998年 | 13篇 |
1997年 | 13篇 |
1996年 | 8篇 |
1995年 | 6篇 |
1994年 | 26篇 |
1993年 | 15篇 |
1992年 | 5篇 |
1991年 | 11篇 |
1990年 | 8篇 |
1989年 | 11篇 |
1987年 | 6篇 |
1986年 | 8篇 |
1985年 | 9篇 |
1984年 | 9篇 |
1983年 | 4篇 |
1982年 | 11篇 |
1981年 | 8篇 |
1980年 | 7篇 |
1979年 | 8篇 |
1978年 | 11篇 |
1977年 | 6篇 |
1976年 | 5篇 |
1975年 | 7篇 |
1974年 | 7篇 |
1972年 | 4篇 |
排序方式: 共有1560条查询结果,搜索用时 46 毫秒
1.
Perković Ivana Beus Maja Schols Dominique Persoons Leentje Zorc Branka 《Molecular diversity》2022,26(1):1-14
Molecular Diversity - In this paper, we report the synthesis of novel hybrids 2–14 based on itaconic acid and fluoroaniline, pyridine, indole and quinoline scaffolds. Itaconic acid is a... 相似文献
2.
Jilloju Parameshwara Chary Persoons Leentje Kurapati Sathish Kumar Schols Dominique De Jonghe Steven Daelemans Dirk Vedula Rajeswar Rao 《Molecular diversity》2022,26(3):1357-1371
A new series of (?±)-(3-(3,5-dimethyl-1H-pyrazol-1-yl)-6-phenyl-6,7-dihydro-5H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-7-yl)(phenyl)methanones were efficiently synthesized starting from 4-amino-5-hydrazinyl-4H-1,2,4-triazole-3-thiol 1, acetyl acetone 2, various aromatic and heterocyclic aldehydes 3 and phenacyl bromides 4. All the newly synthesized compounds were tested for their antiviral and antitumoral activity. It was shown that subtle structural variations on the phenyl moiety allowed to tune biological properties toward antiviral or antitumoral activity. Mode-of-action studies revealed that the antitumoral activity was due to inhibition of tubulin polymerization.
Graphic abstract 相似文献3.
4.
5.
Wenbin Guo Dr. Nathalie Daro Dr. Sébastien Pillet Dr. Mathieu Marchivie Dr. El-Eulmi Bendeif Dr. Elodie Tailleur Dr. Kittipong Chainok Dominique Denux Dr. Guillaume Chastanet Prof. Philippe Guionneau 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(57):12927-12930
The current craze for research around the spin crossover phenomenon can be justified to some extent by the mechanical properties due to the decrease of volume associated with the transition of the metal ion from the HS state to the LS state. As demonstrated here, the molecular complex [Fe(PM-pBrA)2(NCS)2] exhibits, on the contrary, an increase of the unit-cell volume from HS to LS. This counter-intuitive and unprecedented behavior that concerns both the thermal and the photoexcited spin conversions is revealed by a combination of single-crystal and powder X-ray diffraction complemented by magnetic measurements. Interestingly, this abnormal volume change appears concomitant with the wide rotation of a phenyl ring which induces a drastic modification, though reversible, of the structural packing within the crystal. In addition, the light-induced HS state obtained through the Light-Induced Excited Spin-State Trapping shows a remarkably high relaxation temperature, namely T(LIESST), of 109 K, one of the highest so far reported. The above set of quite unusual characteristics opens up new fields of possibilities within the development of spin crossover materials. 相似文献
6.
Influence of P‐Bonded Bulky Substituents on Electronic Interactions in Ferrocenyl‐Substituted Phospholes 下载免费PDF全文
Dominique Miesel Dr. Alexander Hildebrandt Marcus Korb Prof. Dr. Heinrich Lang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(32):11545-11559
2,5‐Diferrocenyl‐1‐Ar‐1H‐phospholes 3 a – e (Ar=phenyl ( a ), ferrocenyl ( b ), mesityl ( c ), 2,4,6‐triphenylphenyl ( d ), and 2,4,6‐tri‐tert‐butylphenyl ( e )) have been prepared by reactions of ArPH2 ( 1 a – e ) with 1,4‐diferrocenyl butadiyne. Compounds 3 b – e have been structurally characterized by single‐crystal XRD analysis. Application of the sterically demanding 2,4,6‐tri‐tert‐butylphenyl group led to an increased flattening of the pyramidal phosphorus environment. The ferrocenyl units could be oxidized separately, with redox separations of 265 ( 3 b ), 295 ( 3 c ), 340 ( 3 d ), and 315 mV ( 3 e ) in [NnBu4][B(C6F5)4]; these values indicate substantial thermodynamic stability of the mixed‐valence radical cations. Monocationic [ 3 b ]+–[ 3 e ]+ show intervalence charge‐transfer absorptions between 4650 and 5050 cm?1 of moderate intensity and half‐height bandwidth. Compounds 3 c – e with bulky, electron‐rich substituents reveal a significant increase in electronic interactions compared with less demanding groups in 3 a and 3 b . 相似文献
7.
8.
Dr. Samuel M. Meier M. Sc. Dominique Kreutz Dr. Lilli Winter M. Sc. Matthias H. M. Klose M. Sc. Klaudia Cseh M. Sc. Tamara Weiss Dr. Andrea Bileck M. Sc. Beatrix Alte Dr. Johanna C. Mader M. Sc. Samir Jana Dr. Annesha Chatterjee Dr. Arindam Bhattacharyya Michaela Hejl Dr. Michael A. Jakupec Priv.-Doz. Dr. Petra Heffeter Prof. Dr. Walter Berger Prof. Dr. Christian G. Hartinger Prof. Dr. Bernhard K. Keppler Prof. Dr. Gerhard Wiche Prof. Dr. Christopher Gerner 《Angewandte Chemie (International ed. in English)》2017,56(28):8267-8271
Organometallic metal(arene) anticancer agents require ligand exchange for their anticancer activity and this is generally believed to confer low selectivity for potential cellular targets. However, using an integrated proteomics-based target-response profiling approach as a potent hypothesis-generating procedure, we found an unexpected target selectivity of a ruthenium(arene) pyridinecarbothioamide (plecstatin) for plectin, a scaffold protein and cytolinker, which was validated in a plectin knock-out model in vitro. Plectin targeting shows potential as a strategy to inhibit tumor invasiveness as shown in cultured tumor spheroids while oral administration of plecstatin-1 to mice reduces tumor growth more efficiently in the invasive B16 melanoma than in the CT26 colon tumor model. 相似文献
9.
Topics that attract public attention can originate from current events or developments, might be influenced by situations in the past, and often continue to be of interest in the future. When respective information is made available textually, one possibility of detecting such topics of public importance consists in scrutinizing, e.g., appropriate press articles using—given the continual growth of information—text processing techniques enriched by computer routines which examine present-day textual material, check historical publications, find newly emerging topics, and are able to track topic trends over time. Information clustering based on content-(dis)similarity of the underlying textual material and graph-theoretical considerations to deal with the network of relationships between content-similar topics are described and combined in a new approach. Explanatory examples of topic detection and tracking in online news articles illustrate the usefulness of the approach in different situations. 相似文献
10.
Abdirahman Elmi Fatouma Mohamed Abdoul-Latif Rosella Spina Franois Dupire Stphanie Philippot Champy Marie-France Hugues Jacobs Dominique Laurain-Mattar 《Molecules (Basel, Switzerland)》2021,26(10)
For the first time, the study of the antioxidant activity, the characterization of the phytoconstituants, and the evaluation of in vitro and in vivo toxicity of A. djiboutiensis leave and latex are performed. The antioxidant activity of both latex (ADL) and the methanolic extract of leaves (ADM) is determined using 1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azino-bis 3-ethylbenzothiazoline-6-sulphonic acid (ABTS) scavenging radical methods and ferric reducing/antioxidant power (FRAP) assay. The phytochemical study of latex is done using Liquid Chromatography-Mass Spectrometry (LC-MS/MS) and a molecular networking-based approach. The evaluation of in vivo toxicity is performed on mice by oral gavage with a suspension of ADL. Our results show that weak antioxidant activity of ADL and ADM in opposition to their high polyphenol, 83.01 mg and 46.4 mg expressed in gallic acid equivalent (GAE)/g of dry weight (DW), respectively, and flavonoid contents 13.12 mg and 4.25 mg expressed in quercetin equivalent (QE)/g dry weight (DW), respectively. Using the Global Natural Products Social Molecular Networking (GNPS) website, nine (9) anthraquinones derivatives, ten (10) chromones derivatives, two (2) flavonols/ chromones isomers are annotated in the molecular network. The treated mice do not display abnormalities in their general physical appearance and biochemistry parameters, compared to the controls. Only glucose and calcium levels are slightly higher in male treated mice compared to the vehicles. 相似文献