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471.
Dr. Roberta Tesch Dr. Christian Becker Dr. Matthias Philipp Müller Dr. Michael Edmund Beck M. Sc. Lena Quambusch Dr. Matthäus Getlik M. Sc. Jonas Lategahn M. Sc. Niklas Uhlenbrock Dr. Fanny Nascimento Costa M. Sc. Marcelo D. Polêto M. Sc. Pedro de Sena Murteira Pinheiro M. Sc. Daniel Alencar Rodrigues Prof. Carlos Mauricio R. Sant'Anna Prof. Fabio Furlan Ferreira Prof. Hugo Verli Prof. Carlos Alberto Manssour Fraga Prof. Daniel Rauh 《Angewandte Chemie (International ed. in English)》2018,57(31):9970-9975
PIK‐75 is a phosphoinositide‐3‐kinase (PI3K) α‐isoform‐selective inhibitor with high potency. Although published structure–activity relationship data show the importance of the NO2 and the Br substituents in PIK‐75, none of the published studies could correctly determine the underlying reason for their importance. In this publication, we report the first X‐ray crystal structure of PIK‐75 in complex with the kinase GSK‐3β. The structure shows an unusual U‐shaped conformation of PIK‐75 within the active site of GSK‐3β that is likely stabilized by an atypical intramolecular Br???NO2 halogen bond. NMR and MD simulations show that this conformation presumably also exists in solution and leads to a binding‐competent preorganization of the PIK‐75 molecule, thus explaining its high potency. We therefore suggest that the site‐specific incorporation of halogen bonds could be generally used to design conformationally restricted bioactive substances with increased potencies. 相似文献
472.
473.
Fu C Aldous L Dickinson EJ Manan NS Compton RG 《Chemical communications (Cambridge, England)》2011,47(25):7083-7085
The evaporation of dissolved ferrocene from non-volatile ionic liquids under a flow of nitrogen gas has been monitored voltammetrically and modelled mathematically. The rate of volatilisation was found to depend on the surface tension of the ionic liquid, and a model is presented. 相似文献
474.
Edmund R. Malinowski 《Analytica chimica acta》1978,103(4):339-354
Based on the theory of error for abstract factor analysis described earlier, a theory of error for target factor analysis is developed. The theory shows how the error in the data matrix mixes with the error in the target test vector. The apparent error in a target test is found to be a vector sum of the real error in the target vector and the real error in the predicted vector. The theory predicts the magnitudes of these errors without requiring any a priori knowledge of the error in the data matrix or the target vector. A reliability function and a spoil function are developed for the purpose of assessing the validity and the worthi-ness of a target vector. Examples from model data, mass spectrometry and nuclear magnetic -resonance spectrometry are presented. 相似文献
475.
In [2] Camillo and Zelmanowitz stated that rings all whose modules are dimension modules are semisimple Artinian. It seem however that the proof in [2] contains a gap and applies to rings with finite Goldie dimension only. In this paper we show that the result indeed holds for all rings with a basis as well as for all commutative rings with Goldie dimension attained. 相似文献
476.
Dr. Markus Follmann Dr. Nils Griebenow Dr. Michael G. Hahn Dr. Ingo Hartung Dr. Franz‐Josef Mais Dr. Joachim Mittendorf Dr. Martina Schäfer Dr. Hartmut Schirok Dr. Johannes‐Peter Stasch Dr. Friederike Stoll Dr. Alexander Straub Prof. Dr. Peter Jeschke Dr. Ralf Nauen Dr. Michael Edmund Beck Dr. Hans‐Wilhelm Engels Dr. Hans‐Georg Pirkl Dr. Reinhard Albers Dr. Rolf W. Albach Dr. Jens Krause Dr. Andreas Hoffmann Dr. Holger Casselmann Dr. Jeff Dormish 《Angewandte Chemie (International ed. in English)》2013,52(36):9333-9333
477.
478.
Summary The synthesis and principle properties of several novel tris[1-(4-X-phenyl)-4,4-dimethylpenta-1, 3-dionato]-iron(III) and manganese(III) complexes, where X=MeO, Me, H, F, Cl and NO2, are described. Magnetic susceptibility measurements in the 4.2–295 K range show a near Curie behaviour and a constant magnetic moment for manganese(III) complexes and for iron complexes, with X=F, Cl or NO2. Iron complexes with ligands having substituents: X=MeO, Me and H, show weak antiferromagnetic interaction (J=ca.–8 cm–1 for the two former compounds) and a decrease in magnetic moment with decreasing temperature. In both manganese(III) and iron(III) complexes the diketonate ligand can be easily replaced by chlorine. Equilibrium constants could be evaluated only for substitution of the third diketonate ligand by chloride in the iron complexes on the basis of spectrophotometric measurements. For manganese chelates, the replacement of the second diketonate by chloride is accompanied by reduction of manganese(III) manganese(II) and free organic radical formation is observed. 相似文献
479.
Kathryn C. Sole Michael B. Mooiman Edmund Hardwick 《Separation & Purification Reviews》2018,47(2):159-178
Ion exchange has traditionally been employed for the purification of water and the removal of metal contaminants from dilute waste streams. More recently, its use in removing trace metallic impurities from hydrometallurgical process streams (with typical background metal concentrations of 50–100 g/L) has increased substantially. It is also used as a primary recovery and concentration unit operation for certain commodities, where both technical and cost advantages become apparent for complex flow sheets. This overview discusses selected modern applications of ion exchange in hydrometallurgical processes for uranium, precious metals, copper, cobalt, nickel and zinc, and identifies some opportunities for the future. 相似文献
480.
The garnets Li3Nd3W2O12 and Li5La3Sb2O12 have been prepared by heating the component oxides and hydroxides in air at temperatures up to 950 °C. Neutron powder diffraction has been used to examine the lithium distribution in these phases. Both compounds crystallise in the space group with lattice parameters a=12.46869(9) Å (Li3Nd3W2O12) and a=12.8518(3) Å (Li5La3Sb2O12). Li3Nd3W2O12 contains lithium on a filled, tetrahedrally coordinated 24d site that is occupied in the conventional garnet structure. Li5La3Sb2O12 contains partial occupation of lithium over two crystallographic sites. The conventional tetrahedrally coordinated 24d site is 79.3(8)% occupied. The remaining lithium is found in oxide octahedra which are linked via a shared face to the tetrahedron. This lithium shows positional disorder and is split over two positions within the octahedron and occupies 43.6(4)% of the octahedra. Comparison of these compounds with related d0 and d10 phases shows that replacement of a d0 cation with d10 cation of the same charge leads to an increase in the lattice parameter due to polarisation effects. 相似文献