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151.
Szabolcs Vass Kristina Haimer Gerhard Meier Markus Klapper Sándor Borbély 《Colloid and polymer science》2002,280(3):245-253
Small-angle neutron scattering experiments were made on poly(methyl methacrylate-block-sodium acrylate-block-methyl methacrylate) [p(MMA-b-NaA-b-MMA)] and p(NaA-b-MMA-b-NaA) solutions by varying the composition and the concentration of the polymer with and without 1 M NaCl added. Scattering
curves could be evaluated by assuming that the polymers aggregate into polydisperse micelles. The experiments support the
expectation that in the case of the p(MMA-b-NaA-b-MMA) block sequence the hydrophilic blocks form closed loops connected by both ends to the micellar cores; in the case of
the p(NaA-b-MMA-b-NaA) block sequence they float freely in the solvent. The micellar cores exert considerable stability against dilution and
added electrolyte. The interaction of charged micelles could be formally described in terms of volume exclusion and the Derjaguin–Landau–Verwey–Overbeek
potential.
Received: 20 December 2000 Accepted: 18 August 2001 相似文献
152.
The analysis of in-plane rigid-body rotations requires phase-shifting methods to determine the direction of rotation in conventional electronic speckle pattern interferometry (ESPI). The phase-shifting procedure makes the real-time measurements impossible. A quasi-real-time method is published recently, where the usual symmetric illumination is combined with a wavelength change before the second exposure. The present paper proposes a device sparing an alternative to this. The symmetric illumination is retained but the wavelength change is replaced by simple illumination direction changes. 相似文献
153.
In this paper, we prove that any subreduct of the class of representable relation algebras whose similarity type includes
intersection, relation composition and converse is a non-finitely axiomatizable quasivariety and that its equational theory
is not finitely based. We show the same result for subreducts of the class of representable cylindric algebras of dimension
at least three whose similarity types include intersection and cylindrifications. A similar result is proved for subreducts
of the class of representable sequential algebras.
Received October 7, 1998; accepted in final form September 10, 1999. 相似文献
154.
Ida Fejs Eszter Kalydi Edit Luca Kukk Mimimorena Seggio Milo Malanga Szabolcs Bni 《Molecules (Basel, Switzerland)》2021,26(17)
In order to better understand the chiral recognition mechanisms of positively charged cyclodextrin (CD) derivatives, the synthesis, the pKa determination by 1H nuclear magnetic resonance (NMR)-pH titration and a comparative chiral capillary electrophoretic (CE) study were performed with two series of mono-substituted cationic single isomer CDs. The first series of selectors were mono-(6-N-pyrrolidine-6-deoxy)-β-CD (PYR-β-CD), mono-(6-N-piperidine-6-deoxy)-β-CD (PIP-β-CD), mono-(6-N-morpholine-6-deoxy)-β-CD (MO-β-CD) and mono-(6-N-piperazine-6-deoxy)-β-CD (PIPA-β-CD), carrying a pH-adjustable moiety at the narrower rim of the cavity, while the second set represented by their quaternarized, permanently cationic counterparts: mono-(6-N-(N-methyl-pyrrolidine)-6-deoxy)-β-CD (MePYR-β-CD), mono-(6-N-(N-methyl-piperidine)-6-deoxy)-β-CD (MePIP-β-CD), mono-(6-N-(N-methyl-morpholine)-6-deoxy)-β-CD (MeMO-β-CD) and mono-(6-N-(4,4-N,N-dimethyl-piperazine)-β-CD (diMePIPA-β-CD). Based on pH-dependent and selector concentration-dependent comparative studies of these single isomer N-heterocyclic CDs presented herein, it can be concluded that all CDs could successfully be applied as chiral selectors for the enantiodiscrimination of several negatively charged and zwitterionic model racemates. The substituent-dependent enantiomer migration order reversal of dansylated-valine using PIP-β-CD contrary to PYP-β-CD, MO-β-CD and PIPA-β-CD was also studied by 1H- and 2D ROESY NMR experiments. 相似文献
155.
The present study focuses on a possibility for improving NO removal efficiency from flue gas by application of powerful sound waves. The sound waves (frequency 6.9-17.2kHz, intensity 144-160dB) are propagated from Hartmann sound generators to a preheated graphite disk inside a vertical reaction tube (height 1.8m, I.D. 105mm). An Ar-NO synthetic mixture (NO 911-934ppm) is blown onto the disk surface to perform reactions in the system C-NO. It is found that the NO reduction rate can be significantly enhanced by the sound waves but the enhancement effect is dependent on the sound frequency, intensity and temperature of disk surface. The better effects are obtained at a temperature of 973K and sound frequencies between 9.6 and 12.4kHz. Under these conditions, the sound application results in 3-5-fold enhancement of NO reduction rate. The obtained effects are explained in terms of gas-phase mass transfer controlling mechanism and of near surface turbulent diffusivity. 相似文献
156.
Systematic chromatography has resulted in the isolation of four geometric isomers as products of iodine-catalysed isomerisation of lutein, 13C NMR spectral analysis has established their stereochemistry as mono-cis luteins with a cis-configured double bond at C-9. C-9', C-13 and C-13', respectively. Carbon-13 NMR has also provided unambiguous stereochemical assignment for the previously isolated four mono-cis capsanthins. 相似文献
157.
158.
Szabolcs Zoltan Szilasi Janos KokaveczRobert Huszank Istvan Rajta 《Applied Surface Science》2011,257(10):4612-4615
This work is about the detailed investigation of the changes of the surface topography, the degree of compaction/shrinkage and its relation to the irradiation fluence and the structure spacing in poly(dimethylsiloxane) (PDMS) patterned with 2 MeV proton microbeam. The irradiated periodic structures consisted of parallel lines with different widths and spacing. To achieve different degrees of compaction, each structure was irradiated with more different fluences. At the irradiated areas the surface topography, the adhesion, the wettability and the rigidity of the surface also changes due to the chemical/structural change of the basic poly(dimethylsiloxane) polymer. The surface topography, the phase modification of the surface, and the connection between them was revealed with using an atomic force microscope (AFM). 相似文献
159.
Eric?Chassande-MottinEmail author Martin?Hendry Patrick?J.?Sutton Szabolcs?Márka 《General Relativity and Gravitation》2011,43(2):437-464
Gravitational waves (GWs) are expected to play a crucial role in the development of multimessenger astrophysics. The combination
of GW observations with other astrophysical triggers, such as from gamma-ray and X-ray satellites, optical/radio telescopes,
and neutrino detectors allows us to decipher science that would otherwise be inaccessible. In this paper, we provide a broad
review from the multimessenger perspective of the science reach offered by the third generation interferometric GW detectors
and by the Einstein Telescope (ET) in particular. We focus on cosmic transients, and base our estimates on the results obtained
by ET’s predecessors GEO, LIGO, and Virgo. 相似文献
160.
Szabolcs Beni John F. K. Limtiaco Cynthia K. Larive 《Analytical and bioanalytical chemistry》2011,399(2):527-539
This review discusses recent developments in analytical methods available for the sensitive separation, detection and structural characterization of heparin contaminants. The adulteration of raw heparin with oversulfated chondroitin sulfate (OSCS) in 2007?C2008 spawned a global crisis resulting in extensive revisions to the pharmacopeia monographs on heparin and prompting the FDA to recommend the development of additional physicochemical methods for the analysis of heparin purity. The analytical chemistry community quickly responded to this challenge, developing a wide variety of innovative approaches, several of which are reported in this special issue. This review provides an overview of methods of heparin isolation and digestion, discusses known heparin contaminants, including OSCS, and summarizes recent publications on heparin impurity analysis using sensors, near-IR, Raman, and NMR spectroscopy, as well as electrophoretic and chromatographic separations. Figure
Schematic illustrating the process for heparin impurity characterization 相似文献