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71.
Emira Kahrović Adnan Zahirović Sandra Kraljević Pavelić Emir Turkušić Anja Harej 《Journal of Coordination Chemistry》2017,70(10):1683-1697
The binuclear Ru(II) complexes with Schiff bases derived from 5-chlorosalicyladehyde and 2-aminopyridine and its 5-substituted salicylideneimine homologues were tested in vitro against cervical carcinoma (HeLa), metastatic colorectal adenocarcinoma (SW620), lung adenocarcinoma (A549), breast adenocarcinoma (MCF-7), and human lung fibroblast (WI-38) cell lines. All compounds showed strong antiproliferative activity with extremely low IC50 values. The compounds expressed strong activity against gram-positive bacteria, Staphylococcus aureus and Enterococcus faecalis. 相似文献
72.
Adnan Zahirović Marina Cindrić Sandra Kraljević Pavelić Mirsada Hukić Anja Harej 《Journal of Coordination Chemistry》2017,70(24):4030-4053
Heteroleptic ruthenium(II) bioflavonoid complexes of quercetin, morin, chrysin, and 3-hydroxyflavone were prepared and their interaction with CT DNA and BSA along with antioxidant and in vitro anticancer and antimicrobial activities was investigated. The formulation and characterization of complexes were achieved through elemental and thermal analysis, mass spectrometry, 1H NMR spectroscopy along with infrared, electronic absorption, and emission spectroscopy as well as square-wave voltammetry, and magnetic and conductivity measurements. Ruthenium(II) is octahedrally coordinated in cationic complex species to two bidentate diimine ligands (2,2′-bipyridine or 1,10-phenanthroline) and one bidentate monobasic flavonoid ligand through 3,4-site of quercetin, morin, and 3-hydroxyflavone or 4,5-site of chrysin. Complexes bind CT DNA by intercalation and binding constants comparable to ethidium bromide or 10 times higher. Binding constants of complexes to BSA were several times higher compared to ibuprofen and diazepam, and suggest that the complexes have a strong affinity to BSA. Antioxidant activity tests showed that the complexes are more potent in terms of radical inhibition compared to the parent flavonoids. Cytotoxic testing revealed that the Ru(II) complex of quercetin with 2,2′-bipyridine co-ligand has good selectivity to breast adenocarcinoma, while the complex of 3-hydroxyflavone with 2,2′-bipyridine co-ligand showed strong cytotoxicity toward all tested cell lines with IC50 ~ 1 μM. All complexes showed moderate activity toward Acinetobacter baumannii, while the Ru(II) complex of 3-hydroxyflavone with 2,2′-bipyridine showed excellent activity toward MRSA and Candida albicans. 相似文献
73.
Patrick J. M. Stals Jeffrey C. Everts Robin de Bruijn Ivo A. W. Filot Maarten M. J. Smulders Rafael Martín‐Rapún Dr. Evgeny A. Pidko Dr. Tom F. A. de Greef Dr. Anja R. A. Palmans Dr. E. W. Meijer Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(3):810-821
N‐Centred benzene‐1,3,5‐tricarboxamides (N‐BTAs) composed of chiral and achiral alkyl substituents were synthesised and their solid‐state behaviour and self‐assembly in dilute alkane solutions were investigated. A combination of differential scanning calorimetry (DSC), polarisation optical microscopy (POM) and X‐ray diffraction revealed that the chiral N‐BTA derivatives with branched 3,7‐dimethyloctanoyl chains were liquid crystalline and the mesophase was assigned as Colho. In contrast, N‐BTA derivatives with linear tetradecanoyl or octanoyl chains lacked a mesophase and were obtained as crystalline compounds. Variable‐temperature infrared spectroscopy showed the presence of threefold, intermolecular hydrogen bonding between neighbouring molecules in the mesophase of the chiral N‐BTAs. In the crystalline state at room temperature a more complicated packing between the molecules was observed. Ultraviolet and circular dichroism spectroscopy on dilute solutions of N‐BTAs revealed a cooperative self‐assembly behaviour of the N‐BTA molecules into supramolecular polymers with preferred helicity when chiral alkyl chains were present. Both the sergeants‐and‐soldiers as well as the majority‐rules principles were operative in stacks of N‐BTAs. In fact, the self‐assembly of N‐BTAs resembles closely that of their carbonyl (C?O)‐centred counterparts, with the exception that aggregation is weaker and amplification of chirality is less pronounced. The differences in the self‐assembly of N‐ and C?O‐BTAs were analysed by density functional theory (DFT) calculations. These reveal a substantially lower interaction energy between the monomeric units in the supramolecular polymers of N‐BTAs. The lower interaction energy is due to the higher energy penalty for rotation around the Ph? NH bond compared to the Ph? CO bond and the diminished magnitude of dipole–dipole interactions. Finally, we observed that mixed stacks are formed in dilute solution when mixing N‐BTAs and C?O BTAs. 相似文献
74.
Ulf H. Strasser Beate Neumann Hans‐Georg Stammler Norbert W. Mitzel Prof. Dr. 《无机化学与普通化学杂志》2010,636(7):1249-1254
The tetrasilyl ethers calix[4]areneOSiMe2R (R = Me, H, vinyl, allyl) were prepared by salt elimination; the calix[4]arene was deprotonated with sodium hydride and subsequently reacted with chlorosilanes ClSiMe2R. In general, DMF was chosen as solvent in order to steer the reactions in terms of a preference for the cone‐conformation of the products. In the case of calix[4]areneOSiMe3 both, partial‐cone‐ and cone‐conformers, were synthesised. All products were characterised by NMR (1H, 13C, 29Si) spectroscopy, mass spectrometry and single‐crystal X‐ray diffraction. 相似文献
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76.
Kauffmann-Weiss S Gruner ME Backen A Schultz L Entel P Fähler S 《Physical review letters》2011,107(20):206105
We exploit the intrinsic structural instability of the Fe(70)Pd(30) magnetic shape memory alloy to obtain functional epitaxial films exhibiting a self-organized nanostructure. We demonstrate that coherent epitaxial straining by 54% is possible. The combination of thin film experiments and large-scale first-principles calculations enables us to establish a lattice relaxation mechanism, which is not expected for stable materials. We identify a low twin boundary energy compared to a high elastic energy as key prerequisite for the adaptive nanotwinning. Our approach is versatile as it allows to control both, nanostructure and intrinsic properties for ferromagnetic, ferroelastic, and ferroelectric materials. 相似文献
77.
We report on an analytical study of a quasicontinuum method in the context of fracture mechanics in a one-dimensional setting. To this end, we compare the asymptotic behaviour of a discrete model with nearest and next-to-nearest neighbour interactions of Lennard-Jones type and its quasicontinuum approximation via Γ-convergence. In case of fracture it turns out that one has to coarse grain in the continuum region and at the atomistic/continuum interface in order to capture the same behavior as the atomistic model, while this is not needed if the boundary conditions are such that the system behaves elastically. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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