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521.
In this paper the effect of temperature on the mechanoluminescence of Au doped phosphors of(Zn,Cd)S is described.It is found that the ML disappears beyond a particular temperature.The temperature dependence of ML intensity follows the relation I =I_T~O(1-TIT_C)~n,where I_T~O is a constant,n is the slop of log I_T versus log(1- TIT_C) plot which lies between 0.9 and 1.10,T_C is the temperature at which ML disappear.It is found that the ML intensity in(Zn,Cd)S:Au disappear at 600 K. 相似文献
522.
Using multicanonical Metropolis simulations we estimate phase transition properties of 3D Potts models for q=4 to 10: The transition temperatures, latent heats, entropy gaps, normalized entropies at the disordered and ordered endpoints, interfacial tensions, and spinodal endpoints. 相似文献
523.
524.
Meenu Thakur B. R. Behera Ruchi Mahajan N. Saneesh Gurpreet Kaur Priya Sharma R. Dubey Kushal Kapoor A. Yadav Neeraj Kumar S. Kumar Kavita Rani P. Sugathan A. Jhingan A. Chatterjee M. B. Chatterjee S. Mandal A. Saxena Santanu Pal S. Kailas Avazbek Nasirov Bakhodir Kayumov 《The European Physical Journal A - Hadrons and Nuclei》2017,53(6):133
525.
526.
D. A. Zatsepin I. R. Shein É. Z. Kurmaev V. M. Cherkashenko S. N. Shamin N. A. Skorikov A. D. Yadav S. K. Dubey 《Physics of the Solid State》2008,50(1):146-151
The local electronic structure of 〈111〉 n-silicon single-crystal samples is studied using Si L 2, 3 x-ray emission spectroscopy. The Si x O y N z system is formed by implanting the samples with an 16O 2 + and 14N 2 + ion molecular beam (the oxygen/nitrogen ratio in the molecular beam is 1:1, the implantation energy is 30 keV, the irradiation fluences vary from 2.0 × 1017 to 1.5 × 1018 cm?2, the samples after the implantation are subjected to rapid thermal annealing in nitrogen at 800°C for 5 min). A comparison of the recorded Si L spectra with the spectra of the reference samples reveals clear correlations between the specific features of the electronic structure of the silicon oxynitride formed upon implantation and the ion fluence. It is shown that the implantation at fluences of 2 × 1017 and 1 × 1018 cm?2 results in the predominant formation of Si3N4, whereas the implantation at a fluence of 1.5 × 1018 cm?2 leads primarily to the formation of SiO2 layers in single-crystal silicon. The most probable factors and mechanisms accounting for such implantation of 16O 2 + and 14N 2 + into the samples under study are discussed. The experimental data obtained are compared with ab initio full-potential linearized augmented plane wave calculations of the band structure. 相似文献
527.
Aggarwal MM Ahammed Z Angelis AL Antonenko V Arefiev V Astakhov V Avdeitchikov V Awes TC Baba PV Badyal SK Bathe S Batiounia B Baumann C Bernier T Bhalla KB Bhatia VS Blume C Bucher D Büsching H Carlén L Chattopadhyay S Decowski MP Delagrange H Donni P Majumdar MR El Chenawi K Dubey AK Enosawa K Fokin S Frolov V Ganti MS Garpman S Gavrishchuk O Geurts FJ Ghosh TK Glasow R Guskov B Gustafsson HA Gutbrod HH Hrivnacova I Ippolitov M Kalechofsky H Kamermans R Karadjev K Karpio K Kolb BW Kosarev I 《Physical review letters》2008,100(24):242301
Neutral pion transverse momentum spectra were measured in p+C and p+Pb collisions at sqrt[S{NN}]=17.4 GeV at midrapidity (2.3 less than or approximately equal eta{lab} less than or approximately equal 3.0) over the range 0.7 less than or approximately equal p{T} less than or approximately equal 3.5 GeV/c. The spectra are compared to pi{0} spectra measured in Pb+Pb collisions at sqrt[S{NN}]=17.3 GeV in the same experiment. For a wide range of Pb+Pb centralities (N{part} less than or approximately equal 300), the yield of pi{0}'s with p{T} greater than or approximately equal 2 GeV/c is larger than or consistent with the p+C or p+Pb yields scaled with the number of nucleon-nucleon collisions (N{coll}), while for central Pb+Pb collisions with N{part}greater than or approximately equal 350, the pi{0} yield is suppressed. 相似文献
528.
We study the Kolmogorov-Johnson-Mehl-Avrami theory of phase conversion in finite volumes. For the conversion time we find the relationship tau(con)=tau(nu)[1+f(d)(q)]. Here d is the space dimension, tau(nu) the nucleation time in the volume V, and f(d)(q) a scaling function. Its dimensionless argument is q=tau(ex)/tau(nu), where tau(ex) is an expansion time, defined to be proportional to the diameter of the volume divided by expansion speed. We calculate f(d)(q) in one, two, and three dimensions. The often considered limits of phase conversion via either nucleation or spinodal decomposition are found to be volume-size dependent concepts, governed by simple power laws for f(d)(q). 相似文献
529.
530.
Ravindranathan S Mallet JM Sinay P Bodenhausen G 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2003,163(2):199-207
Exchange transferred effects in solution-state NMR experiments allow one to determine the conformation of ligands that are weakly bound to macromolecules. Exchange-transferred nuclear Overhauser effect spectroscopy ('TR-NOESY') provides information about internuclear distances in a ligand in the bound state. Recently the possibility of obtaining dihedral angle information from a ligand in the bound state by exchange-transferred cross-correlation spectroscopy ('TR-CCSY') has been reported. In both cases the analysis of the signal amplitudes is usually based on the assumption that rapid exchange occurs between the free and bound forms of the ligand. In this paper we show that the fast exchange condition is not easily attained for observing exchange-transferred cross-correlation effects even in systems where exchange-transferred NOE can be observed. Extensive simulations based on analytical expressions for signal intensities corresponding to fast, intermediate, and slow chemical exchange have been carried out on a test system to determine the exchange regimes in which the fast exchange condition can be fulfilled for successfully implementing TR-NOESY and TR-CCSY. 相似文献