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41.
Guy Guerch Jean-Francois Labarre Roger Lahana Gaston Levy Francois Sournies 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):333-336
Abstract Aziridinocyclophosphazenes N3P3Az6 (code name MYKO 63), N4P4Az8 (code name MYKO 83) and relatives constituted the first generation of anticancer drugs whose efficiency on several rodent neoplasms was made conspicuous in a quantitative manner from 1976 to 1978 both in our Laboratory and by EORTC Screening Pharmacology Groups1. MYKO 63 appeared at that time as a promising drug for industrial development owing to its wide spectrum of activity and its very low mutagenicity2. However, this hope failed as a consequence of a cumulative toxicity which occurs upon heavy polyinjections schedules. In other words, MYKO 63 exhibits an uncomfortable kinetics of action on the tumor - and, consequently, of excretion - presumably due (it was our assumption) to a too high chemical stability of the molecule. 相似文献
42.
Alain Rolland Laurent Pedesseau Jacky Even Samy Almosni Cedric Robert Charles Cornet Jean Marc Jancu Jamal Benhlal Olivier Durand Alain Le Corre Pierre Rale Laurent Lombez Jean-Francois Guillemoles Eric Tea Sana Laribi 《Optical and Quantum Electronics》2014,46(10):1397-1403
In this paper, we present a comprehensive study of high efficiencies tandem solar cells monolithically grown on a silicon substrate using GaAsPN absorber layer. InGaAs(N) quantum dots and GaAsPN quantum wells have been grown recently on GaP/Si susbstrate for applications related to light emission. For photovoltaic applications, we consider the GaAsPN diluted nitride alloy as the top junction material due to both its perfect lattice matching with Si and ideal bandgap energy for current generation in association with the Si bottom cell. Numerical simulation of the top cell is performed. The effect of layer thicknesses and doping on the cell efficiency are evidenced. In these structures a tunnel junction (TJ) is needed to interconnect both the top and bottom sub-cells. We compare the simulated performances of different TJ structures and show that the GaP(n+)/Si(p+) TJ is promising to improve performances of the current–voltage characteristic. 相似文献
43.
Guignard C Jouve L Bogéat-Triboulot MB Dreyer E Hausman JF Hoffmann L 《Journal of chromatography. A》2005,1085(1):137-142
A mass spectrometer was coupled to high-performance anion-exchange chromatography (HPAEC) with the help of electrochemical neutralization of the eluent and post-column addition of lithium chloride for carbohydrate analysis. Parallel selective channels (single ion monitoring) were used to decrease the detection limits and separate unresolved peaks. The mass specific detection allowed the simultaneous analysis of a wide range of sugar alcohols, mono-, di- and oligosaccharides. Carbohydrates extracted from leaves of poplar submitted to drought stress were analyzed using pulsed amperometric detection (PAD), then mass spectrometry. It allowed the confirmation of peak attribution and the identification of salicin as a major compound in the extracts. Different responses to water deficit and re-hydration were obtained for several carbohydrates, suggesting different roles in osmoprotection processes. 相似文献
44.
The interaction between multiwalled carbon nanotubes (MWCNTs) and aqueous poly(diallyl dimethylammonium) chloride (PDDA) was studied by X-ray photoelectron (XPS) and photoacoustic Fourier transform infrared (PA-FTIR) spectroscopies. We have found that the mild sonication of MWCNTs in aqueous PDDA results in a significant improvement of CNT dispersibility and greatly enhances their adhesion to Au and Si substrates. The MWCNT-PDDA interaction is due to the presence of an unsaturated contaminant in the PDDA chain, as confirmed by both XPS and PA-FTIR, which enters into a pi-pi interaction with the CNTs. Electrostatic group repulsions of the coated CNTs then provide the dispersibility and adhesion. 相似文献
45.
Ernest D. Weiler Martin Hausman George A. Miller 《Journal of heterocyclic chemistry》1977,14(5):725-728
Halogenation of a number of 3-alkoxyisothiazoles, occurring exclusively in the 4-position, followed by cyanation led to various carboxylic acid, carboxamide and amine derivatives. Subsequent dealkylation provided 4-substituted-4-isothiazoIin-3-ones. 相似文献
46.
47.
Rheological analysis of highly concentrated w/o emulsions 总被引:2,自引:0,他引:2
Nathalie Jager-Lézer Jean-Francois Tranchant Valérie Alard Can Vu Pierre Cyrill Tchoreloff J.-L. Grossiord 《Rheologica Acta》1998,37(2):129-138
A series of highly concentrated lipophilic cosmetic emulsions were analysed, in order to determine their rheological and
textural properties, as a function of their microstructure. The originality of this study lies in the methodology used, especially
the shear-stress scanning analysis. The results of a very powerful and comprehensive dynamic rheological analysis suggest
the existence of two critical volume fraction values: besides the “close-packed” value φ
c
, a “slack-packed” value φ0, close to 0.60 could be demonstrated. It has been shown that the close-packed structure is stable under shear; in constrast,
the slack-packed configuration, defined as φ0<φ<φ
c
is unstable under shear. A comparison with theoretical models, especially that of Princen, showed good agreement and allowed
the close-packed value φ
c
to be defined more precisely as 0.67. The gap between 0.67 and 0.74 is probably indicative of a highly polydisperse distribution,
as confirmed by microscopic analysis. Flow experiments confirmed the validity of Princen‘s model.
Received: 20 February 1997 Accepted: 20 January 1998 相似文献
48.
Kosareva O Daigle JF Panov N Wang T Hosseini S Yuan S Roy G Makarov V Chin SL 《Optics letters》2011,36(7):1035-1037
Experimentally measured conical emission rings on the blue side of the filament supercontinuum of a 800 nm 50 fs pulse in air are reproduced in simulations with plasma and the third-order Kerr as the nonlinear terms. This agreement indicates plasma as the dominant mechanism arresting the self-focusing collapse. The higher order Kerr terms with the recently measured coefficients stop the collapse at a lower intensity than the plasma does and lead to the spherical angle-wavelength spectrum without blueshifted rings. 相似文献
49.
The preparation and use of multiple polymers attached to a surface plasmon resonance (SPR) sensor for optimization of signal enhancement and minimization of fouling during sensing of biological species has been achieved. These polymers are advantageous compared to the current practice of carboxymethylated-dextran (CM-dextran). The polymers offer a wide range of functionalities and different molecular weights. Using these polymers, the SPR sensors can be fabricated as fast or faster than the CM-dextran sensor. In this study, we investigated the use of nine polymers for SPR biosensors. Polysaccharides, including CM-dextran, CM-hyaluronic acid, hyaluronic acid, and alginic acid, were investigated. Humic acid, polylactic acid, polyacrylic acid, orthopyridyldisulfide-polyethyleneglycol-N-hydroxysuccinimide (OPSS-PEG-NHS) and a synthesized polymer; polymethacrylic-acid-co-vinyl-acetate (PMAVA), were also used. The polymers were chemically attached to a thiol monolayer on the SPR biosensor using carbodiimide chemistry. The polymers were functionalized for binding of anti-myoglobin (anti-MG). The sensor performance was measured using myoglobin (MG) at 25 ng ml−1, a biologically relevant level for myocardial infarction detection. Most polymers offered similar performance to CM-dextran for MG detection in HEPES buffer saline pH 7.4 (HBS). In preliminary studies in bovine serum, each of the candidate polymers demonstrated better performance than CM-dextran. 相似文献
50.
A series of N-alkyl- and N-aryl-t-butyldimethylsilyl amides have been prepared by amination and their structures determined by IR and NMR spectroscopy. Like their trimethylsilyl counterparts, the N-alkyl derivatives exist as amides while the N-aryl derivates exist as amide/imidate mixtures. The percentage of imidate and the free energies of activation for the imidate/amide exchange in the aryl derivatives are greater than those in the trimethylsilyl derivatives. The barriers to rotation in the amide form of the aryl derivatives are similar to those of the trimethylsilyl derivatives. The barrier for rotation in t-butyldimethylsilyl-N-methyl formamide, however, is lower than that of the trimethylsilyl derivative. Isomer ratios and free energies of activation are rationalized in terms of the steric effect of the t-butyl group. 相似文献