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81.
Designs, Codes and Cryptography - In this article, we study locating-dominating codes in binary Hamming spaces $$\mathbb {F}^n$$ . Locating-dominating codes have been widely studied since their... 相似文献
82.
83.
The emission spectra of the lanthanide chelates enable them to act as a donor for several acceptors emitting at different
wavelengths. Fluorescence resonance energy transfer between terbium(III) chelate labeled antibody Fab fragment (donor) and
a 17β-estradiol conjugated to Alexa Fluor 488, 555, 594 or 680 (acceptor) was employed to study the functionality of the terbium(III)
chelate as an efficient donor for several acceptors emitting from green to far-red. During measurement, the sensitized emission
of the acceptor was measured at acceptor specific wavelength. All the tested dyes proved to be efficient acceptors, and they
were successfully used in the competitive homogeneous E2 assay. The highest signal to background ratio and the best assay
performance was obtained with Alexa Fluor 680, due to the very low donor emission background at the far-red area. In addition,
the sensitized emission of both Alexa Fluor 488 and 680 could be measured simultaneously without significant cross talk. 相似文献
84.
We examine the properties of the recently introduced degrees of coherence regarding the phase correlations of the optical field. It is seen that some of these quantities are straightforwardly related to the limits of complete dependence and complete independence of phases, which were used as the extremes of complete coherence and complete incoherence by Zernike in 1938. Certain other coherence measures are not in agreement with these limits in all situations. Our results elucidate the physical meaning of coherence in electromagnetic fields. 相似文献
85.
86.
We derive a spectral interference law that governs the behavior of the four Stokes parameters in Young's two-pinhole experiment with a random electromagnetic beam. In addition to the visibility of intensity fringes, we introduce three new contrast parameters that describe the interference-induced changes in the field's state of partial polarization. The polarization modulation depends on the electric field correlations at the pinholes and is closely related to the two-point Stokes parameters. The results are expected to be particularly useful in polarization interferometry and electromagnetic coherence theory. The formalism is demonstrated with specific examples. 相似文献
87.
Tero Tikka Jussi Ryynänen Kari Halonen 《Analog Integrated Circuits and Signal Processing》2008,54(2):105-111
This paper focuses on the design and measurements of low-noise amplifiers (LNA) targeted for WCDMA base-station applications. In addition, various gain control techniques and the accuracy in noise measurements have been analyzed. Two different LNA designs are presented. Both LNAs can be operated in two gain modes, which are optimized for different base-station configurations. Both designs are implemented using the same 0.25-μm SiGe BiCMOS process, and both designs achieve the NF of 1 dB and IIP3 of ?5 dBm in high gain mode. 相似文献
88.
89.
Tero R Sazaki G Ujihara T Urisu T 《Langmuir : the ACS journal of surfaces and colloids》2011,27(16):9662-9665
Hierarchic structure and anomalous diffusion on submicrometer scale were introduced into an artificial cell membrane, and the spatiotemporal dependence of lipid diffusion was visualized on nanostructured oxide surfaces. We observed the lipid diffusion in supported lipid bilayers (SLBs) on step-and-terrace TiO(2)(100) and amorphous SiO(2)/Si surfaces by single molecule tracking (SMT) method. The SMT at the time resolution of 500 μs to 30 ms achieved observation of the lipid diffusion over the spatial and temporal ranges of 100 nm/millisecond to 1 μm/second. The temporal dependence of the diffusion coefficient in the SLB on TiO(2)(100) showed that the crossover from anomalous diffusion to random diffusion occurred around 10 ms. The surface fine architecture on substrates will be applicable to induce hierarchic structures on the order of 100 nm or less, which correspond to the microcompartment size in vivo. 相似文献
90.
We study a problem considered originally by A. Markov in 1947: Given two finitely generated matrix semigroups, determine whether
or not they contain a common element. This problem was proved undecidable by Markov for 4 x 4 matrices, even in a very restrict
form, and for 3 x 3 matrices by Krom in 1981. Here we give a new proof in the 3 x 3 case which gives undecidability in an
almost as restricted form as the result of Markov. 相似文献