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871.
Dumitru Baleanu Ivo Petras Jihad H. Asad Maria Pilar Velasco 《International Journal of Theoretical Physics》2012,51(4):1253-1258
In this paper we study the fractional Lagrangian of Pais–Uhlenbeck oscillator. We obtained the fractional Euler–Lagrangian
equation of the system and then we studied the obtained Euler–Lagrangian equation numerically. The numerical study is based
on the so-called Grünwald–Letnikov approach, which is power series expansion of the generating function (backward and forward
difference) and it can be easy derived from the Grünwald–Letnikov definition of the fractional derivative. This approach is
based on the fact, that Riemman–Liouville fractional derivative is equivalent to the Grünwald–Letnikov derivative for a wide
class of the functions. 相似文献
872.
873.
Dr. Jakub S. Prauzner‐Bechcicki Szymon Godlewski Dr. Janusz Budzioch Grzegorz Goryl Lukasz Walczak Dr. Petr Sehnal Dr. Irena G. Stará Dr. Ivo Starý Dr. Francisco Ample Prof. Christian Joachim Prof. Marek Szymonski 《Chemphyschem》2010,11(16):3522-3528
The adsorption of individual [11]anthrahelicene molecules and their self‐assembly into monolayer islands on an InSb(001) c(8×2) reconstructed surface is studied with low‐temperature scanning probe microscopy. A racemic mixture is deposited on atomically flat terraces of InSb at room temperature. At lower coverage, the molecules tend to decorate atomic step edges of the substrate. At higher coverage, [11]anthrahelicene molecules form 2D islands. A quasi‐hexagonal ordering of molecules within the layer is identified. Furthermore, it is shown that molecules adsorb with the helical axis almost perpendicular to the substrate. Interference between tunneling through the molecular layer and directly through space is reported. Finally, experimental results are compared to those of theoretical calculations. 相似文献
874.
875.
Ivo Piantanida Mladen Žinić Saška Marczi Ljubica Glavaš‐Obrovac 《Journal of Physical Organic Chemistry》2007,20(4):285-295
Novel bis‐4,9‐diazapyrenium dication has shown reversible pH dependent formation of 4,9‐ diazapyrenium pseudobase in water characteristic for most 4,9‐diazapyrenium derivatives. The compound has formed non‐covalent complexes with nucleotides in water, whose stability is controlled dominantly by aromatic stacking interactions. No cooperativity between two 4,9‐diazapyrenium subunits was observed in binding of nucleotides. Novel bis‐4,9‐diazapyrenium dication formed mono‐intercalative complexes with studied double stranded DNA and RNA. Additional interactions of non‐intercalated part were found to depend significantly on the polynucleotide secondary structure, yielding strong DNA over RNA preference. Appearance of ICD band of 3 was found to be specific for DNA polynucleotides and together with observed destabilisation of double stranded RNA is attributed to the aggregation of compound in one of the RNA grooves. All bis‐4,9‐diazapyrenium dications prepared till now have shown considerable antiproliferative activity against five human tumour cell lines, which suggested mechanism of action by interacting with cell DNA. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
876.
Ivo Vrkoč 《Applications of Mathematics》1999,44(3):243-243
877.
David Sarauli Johannes Tanne Daniel Schäfer Ivo W. Schubart Fred Lisdat 《Electrochemistry communications》2009,11(12):2288-2291
The construction of new mediator-free and fully electroactive protein multilayer electrodes based on DNA and cyt c is demonstrated. The assembly is characterized by a rather high stability, effective electron transfer, and a tunability of the electroactive protein amount by the number of deposited cyt c layers. 相似文献
878.
In this paper we consider the inverse problem of recovering the viscosity coefficient in a dissipative wave equation via boundary measurements. We obtain stability estimates by considering all possible measurements implemented on the boundary. We also prove that the viscosity coefficient is uniquely determined by a finite number of measurements on the boundary provided that it belongs to a given finite dimensional vector space. 相似文献
879.
Five different isotopologues of the benzoic acid dimer and a vibronic band located 57 cm?1 above the electronic origin, which is assigned to the out‐of‐plane butterfly motion, are studied by rotationally resolved UV spectroscopy. From these measurements a ground‐state structure with C2h symmetry is deduced, whereas the symmetry is lowered to Cs in the S1 state. The increase in the center‐of‐mass distance between the two monomers that is found on electronic excitation indicates a decrease in hydrogen‐bond strength. The tunneling splittings in the S0 and S1 states are 1385.2±0.7 and 271.2±0.7 MHz, respectively, corresponding to an increase in barrier height by 7.2 % on electronic excitation. 相似文献
880.
Nonlinear least squares optimization problems in which the parameters can be partitioned into two sets such that optimal estimates
of parameters in one set are easy to solve for given fixed values of the parameters in the other set are common in practice.
Particularly ubiquitous are data fitting problems in which the model function is a linear combination of nonlinear functions,
which may be addressed with the variable projection algorithm due to Golub and Pereyra. In this paper we review variable projection,
with special emphasis on its application to matrix data. The generalization of the algorithm to separable problems in which
the linear coefficients of the nonlinear functions are subject to constraints is also discussed. Variable projection has been
instrumental for model-based data analysis in multi-way spectroscopy, time-resolved microscopy and gas or liquid chromatography
mass spectrometry, and we give an overview of applications in these domains, illustrated by brief case studies. 相似文献