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711.
The steady Navier–Stokes equation is solved to simulate the wind-flow environment of three-dimensional configurations of buildings. The method assumes an incident wind described by a power-law velocity profile. A new method for controlling the two-part nested solution iteration is introduced. The simulation is compared to some published wind-tunnel measurements. 相似文献
712.
R.M. Mihalcea M.E. Webber D.S. Baer R.K. Hanson G.S. Feller W.B. Chapman 《Applied physics. B, Lasers and optics》1998,67(3):283-288
2 , H2O, N2O, and NH3 concentrations in various flowfields using absorption spectroscopy and extractive sampling techniques. An external-cavity
diode laser with a tuning range of 1.953–2.057 μm was used to record absorption lineshapes from measured transitions in the
CO2 4ν2
0+ν3, ν1+2ν2
0+ν3, and 2ν1+ν3 bands, H2O ν2+ν3and ν1+ν2 bands, N2O 2ν1+4ν2
0, ν2
1+2ν3, 3ν1+2ν2
0, and 4ν1 bands, and NH3ν1+ν4 and ν3+ν4 bands. Measured CO2, H2O, and N2O survey spectra were compared to calculations to verify the HITRAN96 database and used to determine optimum transitions for
species detection. Individual lineshape measurements were used to determine fundamental spectroscopic parameters including
the line strength, line-center frequency, and self-broadening coefficient of the probed transition. The results represent
the first measurements of CO2, H2O, N2O, and NH3 absorption near 2.0 μm using room-temperature near-IR diode lasers.
Received: 12 March 1998/Revised version: 7 May 1998 相似文献
713.
R.K. Hanson J.P. Monat C.H. Kruger 《Journal of Quantitative Spectroscopy & Radiative Transfer》1976,16(8):705-713
Absorption of CO i.r. laser radiation by NO has been studied over the temperature range 300°–4000°K using a grating-tunable CO laser in conjunction with a room-temperature absorption cell and a shock tube. The CO laser line with strongest absorption at elevated temperatures was determined to be the V = 7 → 6, J = 12 → 13 line at 1935.4817 cm-1, which is nearly coincident with the 2ΠV = 0 → 1, J = 37/2 → 39/2 transition in NO. The absorption cell measurements (300°K) were used to infer the position of the NO absorption line (a Λ-doublet at 1935.492 and 1935.497 cm-1) as well as collision-broadening parameters in pure NO and NO dilute in foreign gases: 2γ° (collision-broadened full width at half maximum in cm-1 atm-1 at 300°K) = 0.110, NO-NO; 0.072, NO in Ar; 0.069, NO in Kr; 0.109, NO in N2. Calculations of the NO absorption coefficient at 1935.4817 cm-1 are presented for a range of conditions applicable to current studies in combustion and NOx kinetics. Shock tube measurements (630°–4000°K) supporting these calculations are also reported. 相似文献
714.
Burchat PR Schmidke WB Yelton JM Abrams G Amidei D Baden AR Barklow T Boyarski AM Boyer J Breidenbach M Burke DL Butler F Dorfan JM Feldman GJ Gidal G Gladney L Gold MS Goldhaber G Golding L Haggerty J Hanson G Hayes K Herrup D Hollebeek RJ Innes WR Jaros JA Juricic I Kadyk JA Karlen D Lankford AJ Larsen RR LeClaire BW Levi M Lockyer NS Lüth V Matteuzzi C Nelson ME Ong RA Perl ML Richter B Riles K Ross MC Rowson PC Schaad T Schellman H Sheldon PD Trilling GH de la Vaissiere C Wood DR Zaiser aC 《Physical review letters》1985,54(23):2489-2492
715.
Schmidke WB Abrams GS Matteuzzi C Amidei D Baden AR Barklow T Boyarski AM Boyer J Breidenbach M Burchat PR Burke DL Butler F Dieterle WE Dorfan JM Feldman GJ Gidal G Gladney L Gold MS Goldhaber G Golding LJ Haggerty J Hanson G Hayes K Herrup D Hollebeek RJ Innes WR Jaros JA Juricic I Kadyk JA Karlen D Klein SR Lankford AJ Larsen RR LeClaire BW Levi ME Lockyer NS Lüth V Nelson ME Ong RA Perl ML Richter B Riles K Ross MC Rowson PC Schaad T Schellman H Sheldon PD Trilling GH de la Vaissiere C 《Physical review letters》1986,57(5):527-530
716.
Yelton JM Dorfan JM Abrams GS Amidel D Baden AR Barklow T Boyarski AM Boyer J Breidenbach M Burchat P Burke DL Butler F Feldman GJ Gladney LD Gidal G Gold MS Goldhaber G Golding L Haggerty J Hanson G Hayes K Herrup D Hollebeek RJ Innes WR Jaros JA Juricic I Kadyk JA Karlen D Lankford AJ Larsen RR Leclaire BW Levi ME Lockyer NS Lüth V Matteuzzi C Nelson ME Ong RA Perl ML Richter B Riles K Ross MC Rowson PC Schadd T Schellman H Schmidke WB Sheldon PD Trilling GH de la Vaissiere C Wood DR Zaiser C 《Physical review letters》1986,56(8):812-814
717.
Sulfotransferases: structure, mechanism, biological activity, inhibition, and synthetic utility 总被引:4,自引:0,他引:4
Chapman E Best MD Hanson SR Wong CH 《Angewandte Chemie (International ed. in English)》2004,43(27):3526-3548
The sulfonation (also known as sulfurylation) of biomolecules has long been known to take place in a variety of organisms, from prokaryotes to multicellular species, and new biological functions continue to be uncovered in connection with this important transformation. Early studies of sulfotransferases (STs), the enzymes that catalyze sulfonation, focused primarily on the cytosolic STs, which are involved in detoxification, hormone regulation, and drug metabolism. Although known to exist, the membrane-associated STs were not studied as extensively until more recently. Involved in the sulfonation of complex carbohydrates and proteins, they have emerged as central players in a number of molecular-recognition events and biochemical signaling pathways. STs have also been implicated in many pathophysiological processes. As a result, much interest in the complex roles of STs and in their targeting for therapeutic intervention has been generated. Progress in the elucidation of the structures and mechanisms of sulfotransferases, as well as their biological activity, inhibition, and synthetic utility, are discussed in this Review. 相似文献
718.
Stark effects on the phosphorescent states of l-indanone,l-tetralone,and 2,4,5-Trimethylbenzaldehyde
The differences in dipole moments between the ground and the phosphorescent states of l-indanone, l-tetralone, and 2,4,5-trimethylbenzaldehyde using durene and hexamethylbenzene host crystals are determined from spectral line splittings in a static electric field and from intensity modulation in an alternating field. It is concluded that the magnitude of the vector difference in dipole moments characteristic of a 3nπ* excited state for l-indanone is ?2.2 ± 0.1 D and for l-tetralone is ?1.8 ± 0.1 D while the difference characteristic of a 3ππ* excited state for trimethylbenzaldehyde is ± 1.1 ±0.1 D. 相似文献
719.
720.
Hanson EL Guo J Koch N Schwartz J Bernasek SL 《Journal of the American Chemical Society》2005,127(28):10058-10062
A new method is described for surface modification of ITO with an electroactive organic monolayer. This procedure was done to enhance hole injection in an electronic device and involves sequential formation of a monolayer of a pi-conjugated organic semiconductor on the indium tin oxide (ITO) surface followed by doping with a strong electron acceptor. The semiconductor monolayer is covalently bound to the ITO, which ensures strong adhesion and interface stability; reduction of the hole injection barrier in these devices is accomplished by formation of a charge-transfer complex by doping within the monolayer. This gives rise to very high current densities in simple single layer devices and double layer light emitting devices compared to those with untreated ITO anodes. 相似文献