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81.
Jack B. Brown Udayan B. Darji Eric P. Larsen 《Proceedings of the American Mathematical Society》1999,127(1):173-182
We investigate the relationships between the notions of a continuous function being monotone on no interval, monotone at no point, of monotonic type on no interval, and of monotonic type at no point. In particular, we characterize the set of all points at which a function that has one of the weaker properties fails to have one of the stronger properties. A theorem of Garg about level sets of continuous, nowhere monotone functions is strengthened by placing control on the location in the domain where the level sets are large. It is shown that every continuous function that is of monotonic type on no interval has large intersection with every function in some second category set in each of the spaces , and .
82.
Christian L. Pedersen Ole Buchardt Sine Larsen Kenneth J. Watson 《Tetrahedron letters》1973,14(24):2195-2198
83.
84.
85.
N.R. Zangenberg A. Nylandsted Larsen 《Applied Physics A: Materials Science & Processing》2005,80(5):1081-1086
Vacancy-related defects in Si are explored with deep level transient spectroscopy (DLTS). The measurements are performed on-line on irradiated p-type Si and a new trap with the signature (Epa, pa) = (0.18 eV, 6.5×10-15 cm2) – only present at cryogenic temperatures – is studied. Furthermore, the bi-stable boron-vacancy complex is studied and its configuration at low temperatures is investigated and found to have the signature (Epa, pa) = (0.11 eV, 8.2×10-15 cm2). PACS 71.55.Cn; 61.80.Fe; 61.82.Fk; 61.72.Ji 相似文献
86.
[chemical reaction: see text]. Prior to detachment of compounds synthesized on sulfonamide based safety-catch linkers, the molecular anchor has to be activated. This is achieved by alkylation of the nitrogen atom of the N-acylsulfonamide using different established protocols. As an addition to the existing repertoire of activating reagents, we suggest the use of O,N,N'-trialkylisoureas. Besides the demonstration of the feasibility of these mild alkylating agents for this purpose, custom-tailored novel O,N,N'-trialkylisoureas prepared from electron-deficient alcohols are reported. 相似文献
87.
88.
Loscertales IG Barrero A Márquez M Spretz R Velarde-Ortiz R Larsen G 《Journal of the American Chemical Society》2004,126(17):5376-5377
The outer liquid of a two-liquid coaxial electrified jet is gelled before the onset of natural instabilities to yield hollow nanofibers. By using sol-gel chemistry, innocuous solvents such as glycerol and olive oil, and electrohydrodynamics, it is possible to make such structures in a rather straightforward manner. 相似文献
89.
M.M.A.J.?VonckenEmail author J.J.?Schermer G.J.?Bauhuis P.?Mulder P.K.?Larsen 《Applied Physics A: Materials Science & Processing》2004,79(7):1801-1807
The lateral etch rate of AlGaAs in HF in the Epitaxial Lift-Off (ELO) process consists of two parts, an intrinsic and a radius-induced part. The intrinsic part is studied with a new approach in which multiple release layers are introduced in one sample. By letting an essential ELO process parameter vary over the different release layers, this parameter is examined, using only samples from one wafer. In this study, the influence of thickness, aluminium fraction, and doping concentration of the release layer on the lateral etch rate is investigated. For release layers with thicknesses below 10 nm, a positive correlation between thickness and intrinsic etch rate is found. Thicker release layers do not result in higher etch rates. Increasing aluminium fractions in the AlxGa1-xAs release layers result in higher etch rates. For aluminium fractions between 0.3 and 1, this effect covers almost six orders of magnitude. From the width of the V-shaped etch slits in samples that have been etched for 12 hours or more, the selectivity, i.e., the ratio of the etch rate of AlxGa1-xAs to GaAs, is determined. Selectivities between 4.3 and 8.6×105 are found for x=0.3 and x=1, respectively. A variation in silicon doping is found to have no effect on the lateral etch rate, while increased zinc doping raises the etch rate significantly. PACS 81.05.Ea; 68.37.Hk; 81.15.Gh 相似文献
90.
Larsen J Rasmussen BS Hazell RG Skrydstrup T 《Chemical communications (Cambridge, England)》2004,(2):202-203
A disphosphine-palladium(0) complex capable of recognising barbiturates has been prepared. Oxidative addition studies with a barbitiurate:aryl iodide conjugate provided new Pd(ii) complexes where the positioning of the Pd-bound aryl group is controlled by the molecular recognition event. 相似文献