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82.
Cover Picture: Absolute Configuration from Different Multifragmentation Pathways in Light‐Induced Coulomb Explosion Imaging (ChemPhysChem 16/2016) 下载免费PDF全文
Dr. Martin Pitzer Gregor Kastirke Dr. Maksim Kunitski Dr. Till Jahnke Dr. Tobias Bauer Christoph Goihl Florian Trinter Carl Schober Kevin Henrichs Jasper Becht Stefan Zeller Helena Gassert Markus Waitz Andreas Kuhlins Hendrik Sann Felix Sturm Florian Wiegandt Dr. Robert Wallauer Dr. Lothar Ph. H. Schmidt Allan S. Johnson Manuel Mazenauer Benjamin Spenger Sabrina Marquardt Sebastian Marquardt Prof. Dr. Horst Schmidt‐Böcking Prof. Dr. Jürgen Stohner Prof. Dr. Reinhard Dörner Dr. Markus Schöffler Prof. Dr. Robert Berger 《Chemphyschem》2016,17(16):2448-2448
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N-Acylthioureas 1 can be easily transformed into 2,4-diamino-6-aryl-1,3,5-oxadiazinium salts 12, 2,4-diamino-6-aryl-1,3,5-thiadiazinium salts 13,3-amino-5-aryl-1,2,4-dithiazolium salts 19 and 2-acylimino-benzothiazolines 22, respectively by reaction with different electrophiles. The structure of the compounds prepared is confirmed by analytical data as well as by chemical transformations. 相似文献
84.
Baranoff E Curchod BF Frey J Scopelliti R Kessler F Tavernelli I Rothlisberger U Grätzel M Nazeeruddin MK 《Inorganic chemistry》2012,51(1):215-224
Investigations of blue phosphorescent organic light emitting diodes (OLEDs) based on [Ir(2-(2,4-difluorophenyl)pyridine)(2)(picolinate)] (FIrPic) have pointed to the cleavage of the picolinate as a possible reason for device instability. We reproduced the loss of picolinate and acetylacetonate ancillary ligands in solution by the addition of Br?nsted or Lewis acids. When hydrochloric acid is added to a solution of a [Ir(C^N)(2)(X^O)] complex (C^N = 2-phenylpyridine (ppy) or 2-(2,4-difluorophenyl)pyridine (diFppy) and X^O = picolinate (pic) or acetylacetonate (acac)), the cleavage of the ancillary ligand results in the direct formation of the chloro-bridged iridium(III) dimer [{Ir(C^N)(2)(μ-Cl)}(2)]. When triflic acid or boron trifluoride are used, a source of chloride (here tetrabutylammonium chloride) is added to obtain the same chloro-bridged iridium(III) dimer. Then, we advantageously used this degradation reaction for the efficient synthesis of tris-heteroleptic cyclometalated iridium(III) complexes [Ir(C^N(1))(C^N(2))(L)], a family of cyclometalated complexes otherwise challenging to prepare. We used an iridium(I) complex, [{Ir(COD)(μ-Cl)}(2)], and a stoichiometric amount of two different C^N ligands (C^N(1) = ppy; C^N(2) = diFppy) as starting materials for the swift preparation of the chloro-bridged iridium(III) dimers. After reacting the mixture with acetylacetonate and subsequent purification, the tris-heteroleptic complex [Ir(ppy)(diFppy)(acac)] could be isolated with good yield from the crude containing as well the bis-heteroleptic complexes [Ir(ppy)(2)(acac)] and [Ir(diFppy)(2)(acac)]. Reaction of the tris-heteroleptic acac complex with hydrochloric acid gives pure heteroleptic chloro-bridged iridium dimer [{Ir(ppy)(diFppy)(μ-Cl)}(2)], which can be used as starting material for the preparation of a new tris-heteroleptic iridium(III) complex based on these two C^N ligands. Finally, we use DFT/LR-TDDFT to rationalize the impact of the two different C^N ligands on the observed photophysical and electrochemical properties. 相似文献
85.
Hartmann E Brendebach B Polly R Geckeis H Stumpf T 《Journal of colloid and interface science》2011,353(2):562-568
In order to assess the long-term safety of deep radioactive waste repositories, a precise characterization of the different sorption processes on a molecular basis and the exact definition of geochemical boundary conditions for their relevance are of immense importance. Through sorption on various minerals the migration of radionuclides will be hindered and their retention will be ensured. Using time-resolved laser fluorescence spectroscopy (TRLFS) and extended X-ray absorption fine structure (EXAFS) spectroscopy, it was possible to identify outer-sphere sorbed trivalent lanthanides and actinides onto different montmorillonites and illite. Furthermore, the quantification of Cm(III)/clay outer-sphere sorption in D(2)O at different ionic strengths was shown. The results were confirmed by ion exchange model calculations. Finally, the structural parameters of a Sm(III)/clay outer-sphere complex were obtained by EXAFS measurements. 相似文献
86.
Egbert Müller Judith Vajda Djuro Josic Tim Schröder Romain Dabre Tim Frey 《Journal of separation science》2013,36(8):1327-1334
An essential part of the modulation of protein‐binding capacity in hydrophobic interaction chromatography is the buffer‐salt system. Besides using “single” electrolytes, multicomponent electrolyte mixtures may be used as an additional tool. Both the protein solubility and the binding capacity depend on the position of a salt in the so‐called Hofmeister series. Specific interactions are observed for an individual protein‐salt combination. For salt mixtures, selectivity, recovery, and binding capacity do not behave like for the single salts that are positioned in between the two mixed components in the Hofmeister series, as the continuous correlation would suggest. Thus, finding strategies for mixed salts could potentially lead to improved capacities in hydrophobic interaction chromatography. Mixtures of ammonium sulfate, sodium citrate, sodium sulfate, sodium chloride, sodium acetate, and glycine were used to investigate the binding capacities for lysozyme and a monoclonal antibody on various hydrophobic resins. Resin capacity for two investigated proteins increases when mixtures consisting of a chaotropic and a kosmotropic salt are applied. It seems to be related to the rather basic isoelectric points of the proteins. 相似文献
87.
H. K. Barrenscheen Margarete Frey F. Feigl L. T. Fairhall M. Settimj D. Ganassini A. Necke H. Müller Ch. Badham H. B. Taylor G. Moillère F. Weyrauch St. Litzner F. Grendel N. Schoorl H. Begemann A. Berat G. Widmark B. Vahlquist E. M. P. Widmar S. L. Oerskov J. P. Gregersen P. Iversen H. W. Mook D. D. van Sluke W. M. Kirjan W. C. Stadie E. C. Ross K. Lang H. Waelsch Gertrud Klepetar I. St. Lorant L. Kopetz J. W. Heim W. W. Práwdicz-Neminski Z. Babitsch J. F. Reith Th. von Fellenberg R. G. Turner Mina Z. Weeks A. Castille V. Henri 《Analytical and bioanalytical chemistry》1934,98(3-4):147-160
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Max Ziegler und Horst Winkler 《Fresenius' Journal of Analytical Chemistry》1959,166(4):241-242
Zusammenfassung Durch die Anwendung eines H2S-haltigen Laufmittels werden die Ionen Cu2+, Pb2+, Bi3+ und Hg2+ am Startpunkt des Chromatogramms als Sulfide fixiert, während Cd2+ nach kurzer Laufzeit in scharf begrenzter Zone als Sulfid im Chromatogramm nachgewiesen wird. Als Arbeitsgefäße dienen Reagensgläser. Die Spezifitäten liegen für 5 g Cd bei Cd2+Cu2+=12000, Cd2+Pb2+=12000, Cd2+Bi3+=12000, Cd2+Hg2+=1100.Herrn Prof. Dr. O. Glemser, Direktor des Anorganisch-chemischen Insituts der Universität Göttingen, danken wir für Unterstützung der Arbeit. 相似文献