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901.
With the aim of developing potential antimicrobials, a series of novel Ciprofloxacin methylene isatin derivatives incorporating different aromatic aldehydes were synthesized and characterized by FTIR, 1H NMR, Mass spectroscopy and bases of elemental analysis. In addition, the in vitro antibacterial and antifungal properties were tested against some human pathogenic microorganisms by employing the disc diffusion technique. A majority of compounds were showing activity against several of the microorganisms. The relationship between the functional group variation and the biological activity of the evaluated compounds is discussed. From comparisons of the compounds, 3c was determined to be the most active compound. 相似文献
902.
Om Prakash Deepak K. Aneja Khalid Hussain Ravi Kumar Sanjiv Arora Chetan Sharma Kamal R. Aneja 《Journal of heterocyclic chemistry》2012,49(5):1091-1097
A series of new symmetrical 3,6‐bis(aryl)bis([1,2,4]triazolo)[3,4‐a:4′,3′‐c]phthalazines 9a‐l has been conveniently synthesized by oxidative cyclization of 1,4‐bis(substituted benzalhydrazino)phthalazines 8a‐l promoted by iodobenzene diacetate under mild conditions (12 examples, up to 93% yield). All the 12 compounds were tested in vitro for their antibacterial activity against two Gram‐positive bacteria, namely, Staphylococcus aureus, Bacillus subtilis and two Gram‐negative bacteria, namely, Escherichia coli and Pseudomonas aeruginosa. All the synthesized compounds were also tested for their antifungal action against two fungi, Aspergillus niger and Aspergillus flavus. 相似文献
903.
G.K. Surya Prakash Kevin E. Glinton Chiradeep Panja Laxman Gurung Patrice T. Battamack Béla Török Thomas Mathew George A. Olah 《Tetrahedron letters》2012,53(6):607-611
Nafion-H and Nafion SAC-13 are efficient solid Brønsted acid catalysts for the preparation of trifluoromethyl ketimines from benzylamines and trifluoromethylated ketones in high yields. A finely tuned benzylimine–benzaldimine rearrangement by facile 1,3-hydrogen shift has been achieved for the formation of fluorinated benzaldimines in high yields by careful optimization of reaction conditions including attempts under microwave conditions and a flow system. These α-trifluoromethylated benzaldimines are efficient precursors for pharmaceutically important α-trifluoromethylated benzylamines, accessed through their direct acid hydrolysis. 相似文献
904.
Ashok Bankar Mark Winey Divya Prakash Ameeta Ravi Kumar Suresh Gosavi Balu Kapadnis Smita Zinjarde 《Applied biochemistry and biotechnology》2012,168(8):2205-2217
Fly ash collected from an Indian thermal power plant was characterised by scanning electron microscope (SEM)-energy dispersive spectrometer, X-ray diffraction and energy dispersive X-ray fluorescence analysis. The effect of fly ash on the growth and morphology of a metal-tolerant tropical marine yeast, Yarrowia lipolytica NCIM 3589, was studied. The growth of the yeast was unaffected by the presence 0.1, 0.2 or 0.3?% fly ash although the surface-to-volume ratio decreased. The yeast formed biofilms on immobilized fly ash as evidenced by SEM observations. The organism produced citric acid and additional extracellular proteins in the presence of fly ash. Leaching of metals from fly ash by Y. lipolytica was compared with chemical leaching by citric acid. Yeast cells were most effective in leaching Cu (59.41?%) although other metals (Zn, Ni, Cu and Cr) were also extracted. Transmission electron microscope images showed the deposition of metals at the cell wall, cell membrane and in the cytoplasm. This paper thus reports a potential application of Y. lipolytica for removal of different metals from solid waste material (fly ash). 相似文献
905.
906.
Nadia Hundt Quan Hoang Hien Nguyen Prakash Sista Jing Hao John Servello Kumaranand Palaniappan Mussie Alemseghed Michael C. Biewer Mihaela C. Stefan 《Macromolecular rapid communications》2011,32(3):302-308
Poly(3‐hexylthiophene)‐b‐poly(γ‐benzyl‐L ‐glutamate) (P3HT‐b‐PBLG) rod–rod diblock copolymer was synthesized by a ring‐opening polymerization of γ‐benzyl‐L ‐glutamate‐N‐carboxyanhydride using a benzylamine‐terminated regioregular P3HT macroinitiator. The opto‐electronic properties of the diblock copolymer have been investigated. The P3HT precursor and the P3HT‐b‐PBLG have similar UV–Vis spectra both in solution and solid state, indicating that the presence of PBLG block does not decrease the effective conjugation length of the semiconducting polythiophene segment. The copolymer displays solvatochromic behavior in THF/water mixtures. The morphology of the diblock copolymer depends upon the solvent used for film casting and annealing results in morphological changes for both films deposited from chloroform and trichlorobenzene.
907.
Carbon supported Palladium–Nickel alloys with various compositions (Pd–Ni/C) were synthesized by chemical reduction of the co-precipitated Pd and Ni hydroxides on carbon. The structure of these alloys was characterized using X-ray diffraction (XRD) analysis. The catalytic activity of Pd–Ni/C for oxygen reduction reaction (ORR) in alkaline media was studied using a glassy carbon rotating disk electrode (RDE). Pd/C showed ORR activity close to that of Pt/C. The activities of Pd–Ni (3:1)/C and Pd–Ni (1:1)/C were found unchanged compared with that of Pd/C. Ni/C showed about 175 mV lower onset potential than Pt/C, and the activity of Pd–Ni (1:3)/C was observed to be between that of Pd/C and Ni/C. 相似文献
908.
G. K. Surya Prakash Prof. Dr. Fang Wang Nan Shao Thomas Mathew Dr. Golam Rasul Prof. Dr. Ralf Haiges Dr. Timothy Stewart George A. Olah Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(29):5358-5362
Fluoro power : In agreement with theoretical studies on α‐fluorocarbanions an X‐ray crystal structure shows the α‐fluorobis(phenylsulfonyl)methide anion adopts a pyramidal configuration (see picture). High‐level calculations and NMR spectroscopy studies demonstrate that electron‐withdrawing substituents play a crucial role in modulating the properties of bis(phenylsulfonyl)methide anions.
909.
Using density functional theory we present a systematic study of the electronic and magnetic properties of various nickel
clusters and two small bimetallic clusters, Ni
n
Co
m
and Ni
n
Fe
m
(n + m ≤ 6). A detail study of binding energy, magnetic moment and stability function of pure nickel clusters of nuclearity (N) 40–60 have been performed. We observe that the magic numbers occur at N = 43, 46, 49, 53, 55, and 58, which correspond to the most stable clusters. We find that, with increase in substitution of
Co and Fe atoms in Ni cluster, while Ni
n
Co
m
becomes more stable, the Ni
n
Fe
m
clusters become less stable. The significant enhancement of average magnetic moment and suppression of local magnetic moment
of nickel atoms are found in both clusters with increase in Co and Fe concentration. 相似文献
910.
The magnetic ordering of the Fe2P-type Tb6FeTe2, Tb6CoTe2 Tb6NiTe2 and Er6FeTe2 phases (space group P6¯2m) has been investigated through magnetization measurement and neutron powder diffraction. Tb6FeTe2, Tb6CoTe2 and Tb6NiTe2 demonstrate high-temperature ferromagnetic and low-temperature spin reorientation transitions, whereas Er6FeTe2 shows antiferromagnetic transition, only.The Tb6FeTe2 and Tb6NiTe2 phases show same high-temperature collinear ferromagnetic structure, whereas Tb6FeTe2 is the commensurate non-collinear ferromagnet and Tb6NiTe2 is the canted ferromagnetic cone with K1=[0, 0, ±3/10] and K2=[±2/9, ±2/9, 0] wave vectors at 2 K. The magnetic structure of Er6FeTe2 is a flat spiral with K1=[0, 0, ±1/10] at 2 K. The magnetic entropy change for Tb6NiTe2 is ΔSm=−4.86 J/kg K at 229 K for the field change Δμ0H=0-5 T.In addition, novel Fe2P-type Gd6FeTe2, Zr6FeTe2, Hf6FeTe2, Dy6NiTe2, Zr6NiTe2 and Hf6NiTe2 phases have been obtained. 相似文献