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101.
P. G. Reutens F. S. Merritt M. J. Oreglia P. Auchincloss R. E. Blair C. Haber S. R. Mishra E. Oltman M. Ruiz F. J. Sciulli M. H. Shaevitz W. H. Smith R. Zhu R. Coleman H. E. Fisk B. Jin T. Kondo D. Levinthal W. Marsh P. A. Rapidis H. B. White D. Yovanovitch A. Bodek F. Borcherding N. Giokaris K. Lang I. E. Stockdale 《Zeitschrift fur Physik C Particles and Fields》1990,45(4):539-550
We report a measurement of the electroweak parameters sin2θ w and ? based on the ratios of neutral current to charged current events measured in the Fermilab narrow-band neutrino beam at energies of 30–240 GeV. The data are fully corrected for radiative effects, heavy-quark production, and other effects. The best value for sin2θ w obtained, sin2θ w =0.239±0.011, is consistent with the most recent values fromW andZ production, as well as from other neutrino experiments. 相似文献
102.
103.
John M. Beierle Robby Roswanda Petra M. Erne Anthony C. Coleman Wesley R. Browne Ben L. Feringa 《Particle & Particle Systems Characterization》2013,30(3):273-279
The ability to site‐selectively modify micro‐ and nanosized particles has allowed for directed self‐assembly in two and three dimensions. Site‐selective modification of particles can be a complicated task requiring the pre‐organization of particles or enhanced particle fabrication methods. The aluminum silicate, zeolite L has been reported to undergo site‐specific modification at the zeolite channel entrances, post‐fabrication in a solution‐based method. The process by which the channel entrances are site selectively modified is explored here. The preliminary step of charging the zeolite channels with aqueous acid allows for catalysis of covalent bond formation at the channel entrances. Three new end‐specific modification reagents are described based on silanol and silyl ether functional groups. These reagents are purified by column chromatography and characterized by1H NMR spectroscopy and high resolution mass spectrometry (HRMS); they provide for reliable end modification of zeolites L. Preferential reactivity at the channel entrances is also observed. The utility of the approach is demonstrated by modifying zeolite L with adamantane at the channel entrances. Site‐specific self‐assembly with β‐cyclodextrin coated gold nanoparticles can be triggered with a chemical stimulus. The resulting multivalent host‐guest interactions give gold clustered nanoparticles at the ends of the micrometer‐sized zeolites. 相似文献
104.
105.
K. G. Schulz G. Kunisch H. Siegfried R. Otto A. Götz S. Rosier B. Lampe R. Deplanaque F. Eckhardt D. A. Coleman S. R. Snider J. De Clerk F. Tombeur Olli Ant-Wuorinen und F. M. Wieninger 《Fresenius' Journal of Analytical Chemistry》1937,109(1-2):60-63
Ohne Zusammenfassung 相似文献
106.
Anthony W. Coleman C. Mitchell Means Simon G. Bott Jerry L. Atwood 《Journal of chemical crystallography》1990,20(2):199-201
[NBu4][Br3] interacts with C6H6 to form an air-stable liquid clathrate. The tribromide anion reacts with phenol to give para-bromophenol in>95% yield. The HBr which is generated in the reaction combines with the Br– anion to form [Br-H-Br]–. The latter forms the basis for a new liquid clathrate, [NBu4][Br-H-Br]·n C6H6. The parent salt, [NBu4][Br3], crystallizes in the monoclinic space group C2/c witha=12.983(5),b=10.380(7),c=16.222(6) Å,=93.93(3)°, andD
c
=1.47 g cm–3 forZ=4. The final R value is 0.068 based on 787 observed reflections. 相似文献
107.
Coleman WM 《Journal of chromatographic science》2006,44(3):167-173
For the first time, relative distributions of optical and geometrical isomers in selected propylene glycol acetals are determined. Resolution of the four acetal isomers possible through the reaction of racemic propylene glycol (PG) with selected aldehydes is demonstrated. The four isomers are ascribed to the presence of syn and anti geometrical isomers for each optically active PG acetal enantiomer. Thus, the (+) and well as (-) enantiomer are found to have a pair of syn and anti geometrical isomers. The ratio of the (+) and (-) isomers in the product remains at an approximate 50:50 ratio, as expected. However, somewhat unexpectedly, the syn/anti geometrical isomer ratio systematically varies with the nature of the substituent comprising the side chain of the aldehyde. Mechanisms involving electronic and minimal steric effects are advanced as possible reasons for the change in the syn/anti PG acetal ratios. 相似文献
108.
[reaction: see text] A unified strategy for the divergent and stereocontrolled introduction of the (E)- and (Z)-enamide side-chains of oximidines I, II, and III, salicylihalamides A and B, lobatamides A and D, and CJ-12,950 is detailed. The synthesis relied on the copper-promoted C-N coupling of (E)- and (Z)-vinyl iodides with a protected maleimide hemiaminal followed by deprotection and reaction of the resulting (E)- or (Z)-enelactam hemiaminals with O-methylhydroxylamine or propylidenetriphenylphosphorane. 相似文献
109.
110.
Hendricks K.J. Haworth M.D. Englert T. Shiffler D. Baca G. Coleman P.D. Bowers L. Lemke R.W. Spencer T.A. Arman M.J. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1998,26(3):320-325
The Air Force Research Laboratory RKO source has recently demonstrated the ability to convert electron beam power to RF power until the termination of the electron beam pulse, achieving a power of 1.5 GW at an energy of 170 J. These results represent an increase in power of 25-30% in power and energy extracted from this source. This paper discusses the principal research areas encountered in lengthening the RF pulse (FWHM) from 50 ns to the present 120 ns and the associated increase in the RF energy 相似文献