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51.
Detection of Sea Surface Temperature (SST) Using Infrared Band Data of Advanced Very High Resolution Radiometer (AVHRR) in the Gulf of Finland 总被引:1,自引:0,他引:1
Yuanzhi Zhang Jouni Pulliainen Sampsa Koponen Martti Hallikainen 《International Journal of Infrared and Millimeter Waves》2002,23(10):1407-1412
This paper presents the detection of sea surface temperature (SST) in the Gulf of Finland using infrared band data of Advanced Very High Resolution Radiometer (AVHRR). AVHRR imagery is evaluated as a main data source for monitoring SST as a measure of upwelling's dynamic. Sea surface effects (SSE), however, cause a temperature difference between the sea surface skin and water below the surface. Therefore, SSE is taken into account as one of the major error factors in the SST esimation. Further studies will be investigated using both AVHRR and MODIS in the future. 相似文献
52.
Fernando P��rez-Gonz��lez Jouni R?tty? Jari Taskinen 《Mediterranean Journal of Mathematics》2011,8(1):123-135
Natural metrics in the hyperbolic α-Bloch-, weighted Dirichlet- and Q
p
-classes are introduced, and these classes are shown to be complete metric spaces with respect to the corresponding metrics.
Then Lipschitz continuous and compact composition operators C
φ
(f) = f ◦ φ acting from the hyperbolic α-Bloch-class to the hyperbolic weighted Dirichlet- or Q
p
-class are characterized by conditions depending on the symbol φ only. 相似文献
53.
54.
55.
Hiltunen Y Kaartinen J Pulkkinen J Häkkinen AM Lundbom N Kauppinen RA 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2002,154(1):1-5
Long echo time (TE=270 ms) in vivo proton NMR spectra resembling human brain metabolite patterns were simulated for lineshape fitting (LF) and quantitative artificial neural network (ANN) analyses. A set of experimental in vivo 1H NMR spectra were first analyzed by the LF method to match the signal-to-noise ratios and linewidths of simulated spectra to those in the experimental data. The performance of constructed ANNs was compared for the peak area determinations of choline-containing compounds (Cho), total creatine (Cr), and N-acetyl aspartate (NAA) signals using both manually phase-corrected and magnitude spectra as inputs. The peak area data from ANN and LF analyses for simulated spectra yielded high correlation coefficients demonstrating that the peak areas quantified with ANN gave similar results as LF analysis. Thus, a fully automated ANN method based on magnitude spectra has demonstrated potential for quantification of in vivo metabolites from long echo time spectroscopic imaging. 相似文献
56.
Katarina Dimic-Misic Cathy Ridgway Thaddeus Maloney Jouni Paltakari Patrick Gane 《Transport in Porous Media》2014,103(2):155-179
Nano and microfibrillated cellulose (NFC and MFC, respectively, collectively termed MNFC) is known to interact strongly with water, related to its high polarity and surface area. The swelling behaviour acts to form a gel with high water retention properties. The observation that nanocellulose could possibly be used in paper or other coating formulations, as a co-binder, for example, raises a question about the possible effects it could have on coating pore structure. In this study, we analyse the pore structure of pigmented coatings, liquid absorption and permeability, in respect to the influence of partially substituting traditional co-binder carboxymethyl cellulose with MNFC. The contrast between polar water and non-polar liquid, such as alkane, is used to probe the water interactive and extractable in-coating (internal) gel-formation properties of the nanocellulosic materials. These contrasting liquids are important in many processes, such as offset printing, but also in respect to exposure of coatings in general to environmental factors in application. Results show that permeability to liquid water is dramatically reduced when nanocellulosic material is present, though water can permeate by diffusion through the nanocellulose gel network. Long timescale exposure to water during absorption leads to extraction of any soluble salts remaining after the chemical treatment of the fibrillar material during production. Inert alkane, on the other hand, can absorb and permeate freely without interactive hindrance from the nanocellulose, with no extractive effect. Such a construct could in principle be considered for use as an oil-water differential membrane or for slow release concepts in aqueous systems by loading soluble deliverable materials within the nanocellulosic gel. 相似文献
57.
Fernando Pérez-González Jouni Rättyä 《Journal of Mathematical Analysis and Applications》2009,359(2):543-57
Short proofs of the following results concerning a bounded conformal map g of the unit disc D are presented: (1) logg′ belongs to the Dirichlet space if and only if the Schwarzian derivative Sg of g satisfies Sg(z)(1−2|z|)∈L2(D); (2) logg′∈VMOA if and only if 2|Sg(z)|3(1−2|z|) is a vanishing Carleson measure on D. Analogous results for Besov and Qp,0 spaces are also given. 相似文献
58.
In this paper, the ordered set of rough sets determined by a quasiorder relation R is investigated. We prove that this ordered set is a complete, completely distributive lattice. We show that on this lattice
can be defined three different kinds of complementation operations, and we describe its completely join-irreducible and its
completely meet-irreducible elements. We also characterize the case in which this lattice is a Stone lattice. Our results
generalize some results of J. Pomykała and J. A. Pomykała (Bull Pol Acad Sci, Math, 36:495–512, 1988) and M. Gehrke and E. Walker (Bull Pol Acad Sci, Math, 40:235–245, 1992) in case R is an equivalence. 相似文献
59.
60.
The electron impact fragmentations of several derivatives of 2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane have been examined by means of high resolution and metastable ion analysis. The principal fragmentation route for bicyclophosphites, phosphates and phosphorothionates involves a loss of formaldehyde, followed by a loss of the PO2X and HPO2X groups (X = -, O, S). The behaviour of phosphoroselenates is quite different, due partly to the favoured loss of selenium from the molecular ion before further fragmentation. Fragmentation through C? O bond breaking and a rearranged molecular ion is dependent on the exocyclic chalcogen atom (-, O, S, Se) on phosphorus. The reactions have been rationalized in terms of 1- and 4-substitutions. 相似文献