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601.
Weisbach N Baranová Z Gauthier S Reibenspies JH Gladysz JA 《Chemical communications (Cambridge, England)》2012,48(61):7562-7564
The platinum butadiynyl complex trans-(C(6)F(5))(p-tol(3)P)(2)Pt(C≡C)(2)H and a CuI adduct of a 1,10-phenanthroline based 33-membered macrocycle react in the presence of K(2)CO(3) and I(2) or O(2) to give a rotaxane (ca. 9%) in which the macrocycle is threaded by the sp carbon chain of trans,trans-(C(6)F(5))(p-tol(3)P)(2)Pt(C≡C)(4)Pt(Pp-tol(3))(2)(C(6)F(5)). The crystal structure and macrocycle/axle electronic interactions are analyzed in detail. 相似文献
602.
Gendron R Kumar MR Paradis H Martin D Ho N Gardiner D Merschrod SE Poduska KM 《Macromolecular bioscience》2012,12(3):360-366
Therapies for corneal disease and injury often rely on artificial implants, but integrating cells into synthetic corneal materials remains a significant challenge. The electrochemically formed collagen-based matrix presented here is non-toxic to cells and controls the proliferation in the corneal fibroblasts seeded onto it. Histology and biomolecular studies show a behavior similar to corneal stromal cells in a native corneal environment. Not only is this result an important first step toward developing a more realistic, multi-component artificial cornea, but it also opens possibilities for using this matrix to control and contain the growth of cells in engineered tissues. 相似文献
603.
Dr. Haakan N. Joensson Prof. Helene Andersson Svahn 《Angewandte Chemie (International ed. in English)》2012,51(49):12176-12192
Droplet microfluidics allows the isolation of single cells and reagents in monodisperse picoliter liquid capsules and manipulations at a throughput of thousands of droplets per second. These qualities allow many of the challenges in single‐cell analysis to be overcome. Monodispersity enables quantitative control of solute concentrations, while encapsulation in droplets provides an isolated compartment for the single cell and its immediate environment. The high throughput allows the processing and analysis of the tens of thousands to millions of cells that must be analyzed to accurately describe a heterogeneous cell population so as to find rare cell types or access sufficient biological space to find hits in a directed evolution experiment. The low volumes of the droplets make very large screens economically viable. This Review gives an overview of the current state of single‐cell analysis involving droplet microfluidics and offers examples where droplet microfluidics can further biological understanding. 相似文献
604.
Emília Illeková Helene Lefaix Frederic Prima Dušan Janičkovič Peter Švec 《Journal of Thermal Analysis and Calorimetry》2010,99(3):957-963
The influence of the solidification rate, the thermal stability, and devitrification process of the rapidly solidified Ti45Zr38Ni17 alloy have been examined on ribbons prepared by the planar flow casting method. Differential scanning calorimetry in the
continuous heating mode, X-ray diffraction, and electron microscopy techniques were applied. Comparison of the so-obtained
microstructures revealed the competition between icosahedral quasi-crystalline and β-Ti(Zr) phases, both dispersed in an amorphous
matrix. It has been found that the decomposition process of rapidly quenched ribbons consists of the sequence of several independent
exothermic and endothermic reactions involving the additional precipitation of quasi-crystalline nanoparticles and both irreversible
and reversible changes between the unstable high-temperature β and stable low-temperature α phases. The formation of the intermetallics
as well as the transformation of quasi-crystals into Laves phase has been observed at higher temperatures in all ribbons. 相似文献
605.
606.
Martin Röder Helene Filbert Thomas Holzhauser 《Analytical and bioanalytical chemistry》2010,398(5):2279-2288
Food-allergic individuals have to strictly avoid the offending food because no causative immunotherapies are available. Thus,
reliable labelling of allergenic ingredients or precautionary labelling of cross-contacts with potential allergens is of major
importance. Verification of compliance with labelling requirements and identification of cross-contacts demand test methods
that enable the specific and sensitive detection of the analyte. Brazil nut (Bertholletia excelsa) is such a food commodity with allergenic potential. We describe the development of a novel qualitative real-time polymerase
chain reaction (PCR) specific for Brazil nut DNA and its comparison with a qualitative commercially available lateral flow
device (LFD) that detects Brazil nut protein. Specificity was investigated with 58 foods, and no false-positive reactions
were observed in real-time PCR. The sensitivity was investigated with spiked chocolate and incurred dough samples as well
as cookies baked thereof. The simultaneous spiking of matrices with identical amounts of Brazil nut and peanut between 5 and
100,000 mg/kg allowed the verification of the spike quality with two peanut-specific enzyme-linked immunosorbent assay. The
real-time PCR detected Brazil nut in all three matrices down to the lowest investigated spike level of 5 mg/kg. The real-time
PCR results from the analysis of 15 retail samples were confirmed by LFD results and were in concordance with the labelling
of products. The real-time PCR showed unparalleled specificity, and primary data indicated potentially quantitative features
in spiked and retail samples. Because of entirely reproducible chemistry of this real-time PCR, this is the first generally
available Brazil nut-specific detection method with an appropriate sensitivity to help avoid severe allergic reactions for
Brazil nut-allergic individuals. 相似文献
607.
N. Gauthier 《International Journal of Mathematical Education in Science & Technology》2013,44(7):937-944
Two identities for the Bernoulli and for the Euler numbers are derived. These identities involve two special cases of central combinatorial numbers. The approach is based on a set of differential identities for the powers of the secant. Generalizations of the Mittag–Leffler series for the secant are introduced and used to obtain closed-form expressions for the coefficients. 相似文献
608.
609.
We report an experimental study of ultra-high-frequency chaotic dynamics generated in a delay-dynamical electronic device. It consists of a transistor-based nonlinearity, commercially-available amplifiers, and a transmission-line for feedback. The feedback is band-limited, allowing tuning of the characteristic time-scales of both the periodic and high-dimensional chaotic oscillations that can be generated with the device. As an example, periodic oscillations ranging from 48 to 913 MHz are demonstrated. We develop a model and use it to compare the experimentally observed Hopf bifurcation of the steady-state to existing theory [Illing and Gauthier, Physica D 210, 180 (2005)]. We find good quantitative agreement of the predicted and the measured bifurcation threshold, bifurcation type and oscillation frequency. Numerical integration of the model yields quasiperiodic and high dimensional chaotic solutions (Lyapunov dimension approximately 13), which match qualitatively the observed device dynamics. 相似文献
610.
We present a novel homogeneous (“mix‐incubate‐read”) droplet microfluidic assay for specific protein detection in picoliter volumes by fluorescence polarization (FP), for the first time demonstrating the use of FP in a droplet microfluidic assay. Using an FP‐based assay we detect streptavidin concentrations as low as 500 nM and demonstrate that an FP assay allows us to distinguish droplets containing 5 μM rabbit IgG from droplets without IgG with an accuracy of 95%, levels relevant for hybridoma screening. This adds to the repertoire of droplet assay techniques a direct protein detection method which can be performed entirely inside droplets without the need for labeling of the analyte molecules. 相似文献