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81.
Stefano Agnello Michael Brand Mathieu F. Chellat Silvia Gazzola Rainer Riedl 《Angewandte Chemie (International ed. in English)》2019,58(11):3300-3345
The natural phenomenon of drug resistance is a widespread issue that hampers the performance of drugs in many major clinical indications. Antibacterial and antifungal drugs are affected, as well as compounds for the treatment of cancer, viral infections, or parasitic diseases. Despite the very diverse set of biological targets and organisms involved in the development of drug resistance, the underlying molecular mechanisms have been identified to understand the emergence of resistance and to overcome this detrimental process. Detailed structural information on the root causes for drug resistance is nowadays frequently available, so next‐generation drugs can be designed that are anticipated to suffer less from resistance. This knowledge‐based approach is essential for fighting the inevitable occurrence of drug resistance. 相似文献
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Antonio Monari Jose Pitarch‐Ruiz Gian Luigi Bendazzoli Stefano Evangelisti Jose Sanchez‐Marin 《International journal of quantum chemistry》2010,110(4):874-884
The high‐spin electronic states for lithium, sodium, and potassium four‐atom clusters were studied. In particular, we performed coupled cluster geometry optimization of the quintet state in tetrahedral geometry. The quintet state of these systems is characterized by having all the valence electron unpaired, giving rise to the so‐called no‐pair bonding. Single‐point full configuration interaction computations on the equilibrium geometries for the various clusters are also presented. The analysis of the valence orbitals in a localized representation confirms the importance of the p atomic orbitals to explain this unusual type of bond. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 相似文献
87.
Stefano Caramori Dr. Jérôme Husson Dr. Marc Beley Prof. Carlo A. Bignozzi Prof. Roberto Argazzi Dr. Philippe C. Gros Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(8):2611-2618
Mixtures of polypyridine FeII and CoII complexes are used as electron mediators in Ru–thienyltpy‐sensitised solar cells (tpy=terpyridine). The use of the metalorganic redox couples allows for improved charge‐collection efficiency with respect to the classical iodide/iodine couple which, when associated to Ru–tpy2 dyes, usually produces poor performance. The improved charge collection is explained by a combination of effective dye regeneration and decreased recombination with the oxidised electrolyte on the basis of data obtained by transient spectroscopy and photoelectrochemical measurements. The efficiency of the regeneration cascade is also critically dependent upon the ability of the CoII complex to intercept FeIII centres, as clearly indicated by chronocoulometry experiments. 相似文献
88.
Lorenzo Di Terlizzi Prof. Stefano Protti Prof. Davide Ravelli Prof. Maurizio Fagnoni 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(26):e202200313
With the aim of generating new, thermally inaccessible diradicals, potentially able to induce a double-strand DNA cleavage, the photochemistry of a set of chloroaryl-substituted carboxylic acids in polar media was investigated. The photoheterolytic cleavage of the Ar−Cl bond occurred in each case to form the corresponding triplet phenyl cations. Under basic conditions, the photorelease of the chloride anion was accompanied by an intramolecular electron-transfer from the carboxylate group to the aromatic radical cationic site to give a diradical species. This latter intermediate could then undergo CO2 loss in a structure-dependent fashion, according to the stability of the resulting diradical, or abstract a hydrogen atom from the medium. In aqueous environment at physiological pH (pH=7.3), both a phenyl cation and a diradical chemistry was observed. The mechanistic scenario and the role of the various intermediates (aryl cations and diradicals) involved in the process was supported by computational analysis. 相似文献
89.
Giovanni Fronza Claudio Fuganti Piero Grasselli Stefano Servi 《Tetrahedron letters》1985,26(40):4961-4964
Baker's yeast mediated reduction of the α-acetoxy ketones (1)–(3) proceeds with high enantio- and stereoselectivity to give the carbinols (4)–(6), easily converted into the masked chiral deoxy sugars (12)–(14), from which {=D}- and {=L}-deoxysugars have been obtained. 相似文献
90.
Ricardo Bossio Stefano Marcaccini Valerio Parrini Roberto Pepino 《Journal of heterocyclic chemistry》1985,22(4):1147-1148
2-(Benzimidazol-2-ylamino)pyridine (4a) , 2-(benzimidazol-2-ylamino)pyrazine (4b) , and 2-(benzimidazol-2-ylamino)thiazole (4c) underwent a ring-closure reaction on treatment with phosgene affording 6H-pyrimido-[1′,2′:5,4][1,3,5]triazino[1,2-a]benzimidazol-6-one (1a) , 6H-pyrazino[1′,2′:5,4][1,3,5]triazino[1,2-a]benzimidazol-6-one (1b) , and 5H-thiazolo[2′,3′:4,5][1,3,5]triazino[1,2-a]benzimidazol-5-one (1c) respectively. The structure of these hitherto unknown heterocyclic systems was confirmed by their ir and mass spectra. 相似文献