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41.
We identify conditions under which correlations resulting from quantum measurements performed on macroscopic systems (systems composed of a number of particles of the order of the Avogadro number) can be described by local realism. We argue that the emergence of local realism at the macroscopic level is caused by an interplay between the monogamous nature of quantum correlations and the fact that macroscopic measurements do not reveal properties of individual particles. 相似文献
42.
We give a heuristic proof of a conjecture of Hardy and Littlewood concerning the density of prime pairs to which twin primes and Sophie Germain primes are special cases. The method uses the Ramanujan-Fourier series for a modified von Mangoldt function and the Wiener-Khintchine theorem for arithmetical functions. The failing of the heuristic proof is due to the lack of justification of interchange of certain limits. Experimental evidence using computer calculations is provided for the plausibility of the result. We have also shown that our argument can be extended to the m-tuple conjecture of Hardy and Littlewood. 相似文献
43.
Kamsali Murali Mohan Achari Chinnasamy Ramaraj Ramanathan 《Tetrahedron: Asymmetry》2017,28(6):830-836
A conformationally rigid chiral molecule LB-I with Lewis basic site has been designed and synthesized in racemic form from ferrocene via Lewis acid mediated diastereoselective cyclization of hydroxy lactam. Both isomers were successfully obtained in enantiomerically pure form through classical resolution using dibenzoyl-d-tartaric acid as the chiral resolving agent in acetone. The nature of the diastereomeric salt formed in the resolution process was investigated by single crystal X-ray crystallographic studies. The absolute configuration of (+)-LB-I was unambiguously assigned as (S,Rp) by single crystal analysis of the salt I obtained from precipitate fraction containing (+)-LB-I and dibenzoyl-d-tartaric acid. 相似文献
44.
The effect of electric field assisted annealing on the microstructure, composition and ionic conductivity properties in CeO2/YSZ oxide heterostructures have been investigated using molecular dynamics simulations. Amorphization–recrystallization steps were performed with and without external electric field of strength 10?MV/cm along three different orientations: in-plane (YZ), normal (X) and 45° resultant (XY) with respect to the oxide heterointerfaces. The microstructural and compositional differences at the interfaces and in the interior of the oxide heterolayers were evaluated and were found to show a clear correlation with the orientations of the applied field. In particular, the XY configuration displayed a compressive lattice strain of ~9% along with a reduced oxygen vacancy concentration when compared to the others. Ionic density profiles suggest pronounced segregation (~60% higher compared to the average value in the interior) of yttrium ions closer to the YSZ/CeO2 interface for the XY configuration. Other configurations exhibit minimal to no such variations. These microstructural differences are found to affect the number of mobile charge carriers and the activation barriers associated with ionic migration through the oxide lattice and consequently, influence the ionic conductivity. 相似文献
45.
Precipitates of ceria were synthesized by homogeneous precipitation method using cerium nitrate and hexamethylenetetramine
at 80°C. The precipitates were ground to fine particles of average size ∼0.7 μm. Circular disks with 10 mm diameter, 2 and
3 mm thickness were prepared from the green compacts by sintering at 1300° C for three different sintering times. Evolution
of the pore structures in these specimens with sintering time was investigated by small-angle neutron scattering (SANS). The
results show that the peak of the pore size distribution shifts towards the larger size with increasing sintering time although
the extent of porosity decreases. This indicates that finer pores are eliminated from the system at a faster rate than the
coarser ones as sintering proceeds and some of the finer pores coalesce to form bigger ones. 相似文献
46.
47.
Proceedings - Mathematical Sciences - Benzophenone and paranitrotoluene have been studied in the solid and fused states. Their solutions in methyl alcohol have also been investigated and the... 相似文献
48.
49.
R. Ramanathan 《Journal of Computational and Applied Mathematics》2003,160(1-2):259-263
A covariant generalisation of Wigner function proposed by us some years ago is reviewed, and its remarkable and useful properties are elucidated; its being a natural solution to a relativistically covariant Liouville equation is also demonstrated. 相似文献