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191.
JM Chatterjee M Saha Sarkar S Bhattacharya P Banerjee S Sarkar RP Singh S Murulithar RK Bhowmik 《Pramana》2001,57(1):165-169
High-spin states of 95,97Mo (Z=42, N=53,55) nuclei have been investigated through 82Se(18O, xn) reaction at Eb=60 MeV. The level scheme in 95Mo has been observed upto ≏ 10 MeV in the present experiment. The level structure shows mainly single particle character.
In 97Mo, the ground state level sequence has been extended to ≏ 4.5 MeV while the previous information had been up to 2.4 MeV.
A negative parity band built on 1437 keV (11/2−) excited state has been extended to 5.5 MeV. The structure seems to show a coexistence of single particle and collective
modes of excitation. Properties of both the nuclei have been compared with shell model calculations using OXBASH. 相似文献
192.
The nucleus 30 65 Zn was studied using the 52Cr(16O, 2pn)65Zn reaction at a beam energy of 65 MeV. The level scheme is extended up to an excitation energy of 10.57 MeV for spin-parity (41/2?) with several newly observed transitions placed in it. 相似文献
193.
194.
Ingebrigtsen TS Toxvaerd S Heilmann OJ Schrøder TB Dyre JC 《The Journal of chemical physics》2011,135(10):104101
An algorithm is derived for computer simulation of geodesics on the constant-potential-energy hypersurface of a system of N classical particles. First, a basic time-reversible geodesic algorithm is derived by discretizing the geodesic stationarity condition and implementing the constant-potential-energy constraint via standard Lagrangian multipliers. The basic NVU algorithm is tested by single-precision computer simulations of the Lennard-Jones liquid. Excellent numerical stability is obtained if the force cutoff is smoothed and the two initial configurations have identical potential energy within machine precision. Nevertheless, just as for NVE algorithms, stabilizers are needed for very long runs in order to compensate for the accumulation of numerical errors that eventually lead to "entropic drift" of the potential energy towards higher values. A modification of the basic NVU algorithm is introduced that ensures potential-energy and step-length conservation; center-of-mass drift is also eliminated. Analytical arguments confirmed by simulations demonstrate that the modified NVU algorithm is absolutely stable. Finally, we present simulations showing that the NVU algorithm and the standard leap-frog NVE algorithm have identical radial distribution functions for the Lennard-Jones liquid. 相似文献
195.
A species-specific isotope dilution technique for accurate determination of sulfur species in low- and high-boiling petroleum
products was developed by coupling capillary gas chromatography with quadrupole ICP-MS (GC-ICP-IDMS). For the isotope dilution
step 34S-labeled thiophene, dibenzothiophene, and mixed dibenzothiophene/4-methyldibenzothiophene spike compounds were synthesized
on the milligram scale from elemental 34S-enriched sulfur. Thiophene was determined in gasoline, ‘sulfur-free’ gasoline, and naphtha. By analyzing reference material
NIST SRM 2296, the accuracy of species-specific GC-ICP-IDMS was demonstrated by an excellent agreement with the certified
value. The detection limit is always limited by the background noise of the isotope chromatograms and was determined for thiophene
to be 7 pg absolute, which corresponds to 7 ng sulfur/g sample under the experimental conditions used. Dibenzothiophene and
4-methyldibenzothiophene were determined in different high-boiling petroleum products like gas oil, diesel fuel, and heating
oil. In this case a large concentration range from about < 0.04 to more than 2,000 μg g−1 was covered for both sulfur species. By parallel GC-ICP-MS and GC-EI-MS experiments (EI-MS electron impact ionization mass
spectrometry) the substantial influence of co-eluting hydrocarbons on the ICP-MS sulfur signal was demonstrated, which can
significantly affect results obtained by external calibration but not those by the isotope dilution technique. 相似文献
196.
Sänger I Heilmann JB Bolte M Lerner HW Wagner M 《Chemical communications (Cambridge, England)》2006,(19):2027-2029
Reaction of [(fc)3(Li)6.(TMEDA)2] with FeCl2 gives the pentanuclear iron complex [(fc)3(Fe)2(Li)2.(TMEDA)2] featuring two ferra[1]ferrocenophane moieties bridged by a 1,1'-ferrocenediyl unit; the non-ferrocene Fe(II) ions are tetra-coordinate and adopt a high-spin state. 相似文献
197.
We report a measurement of the electron temperature in a plasma generated by a high-intensity laser focused into a jet of neon. The 15?eV electron temperature is determined using an analytic solution of the plasma equations assuming local thermodynamic equilibrium, initially developed for ultracold neutral plasmas. We show that this analysis method accurately reproduces more sophisticated plasma simulations in our temperature and density range. While our plasma temperatures are far outside the typical "ultracold" regime, the ion temperature is determined by the plasma density through disorder-induced heating just as in ultracold neutral plasma experiments. Based on our results, we outline a pathway for achieving a strongly coupled neutral laser-produced plasma that even more closely resembles ultracold neutral plasma conditions. 相似文献
198.