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21.
N. Kawamura I. Higashino Y. Kimura M. Fujioka S. Hayashibe 《Zeitschrift für Physik A Hadrons and Nuclei》1994,348(3):173-176
Nuclearg-factors of the 1229 keV 13+/2 and 2911 keV 21+/2 level and the half-life of the 1229 keV level have been measured to beg(1229)=0.058(5),g(2911)=0.69(12) andT
1/2 (1229)=6.79(2) ns. The experimental g-factors show that the 1229 keV level has a dominant configuration of (f
7/23–), and the 2911 keV level has an almost pure (f
7/27–), configuration.The authors would like to thank the crew of CYRIC for the operation of the cyclotron. 相似文献
22.
Isozaki T Fujikawa T Takezoe H Fukuda A Hagiwara T Suzuki Y Kawamura I 《Physical review. B, Condensed matter》1993,48(18):13439-13450
23.
24.
Masahiro Manabe Toshihiro Ochi Hideo Kawamura Hajime Katsu-ura Masaki Shiomi Mandeep Singh Bakshi 《Colloid and polymer science》2005,283(7):738-746
The partial molar volumes (Va) of 1-alkanols (carbon number, m=5, 6, 7) in - and -cyclodextrin (CD) solutions at 5.00 mmol kg–1 have been determined as a function of alkanol concentration (Ca) between 293.2 and 308.2 K by using a dilatometer. It has been observed that with an increase in Ca, Va increased in -CD solution but decreased in -CD solution, asymptotically to a value of Va in CD-free water. The dependence of Va on Ca provided the binding constant (K) of 1:1 complex, the volume change in complex formation, and the partial molar volume of complex itself. The complex formation mechanism has been discussed on the basis of these values and their carbon number dependences in the respect of geometric behavior, hydrophobic interaction, and van der Waals interaction. It is concluded that the CD cavity in water is not rigid but flexible for fitting in nicely with guest molecule. 相似文献
25.
Okada Y Yokozawa M Akiba M Oishi K O-kawa K Akeboshi T Kawamura Y Inokuma S Nakamura Y Nishimura J 《Organic & biomolecular chemistry》2003,1(14):2506-2511
A variety of aromatic compounds with both activating and deactivating substituents were brominated with sodium monobromoisocyanurate (SMBI) 1, diethyl ether, diethyl ether-methanesulfonic acid, trifluoroacetic acid, or sulfuric acid were employed as solvents. Thus nitrobenzene was conveniently brominated in sulfuric acid, benzene was readily monobrominated in diethyl ether-methanesulfonic acid, and phenol was selectively brominated at the ortho position under mild conditions in refluxing diethyl ether. With substituents that are easily protonated, trifluoroacetic acid may be employed as solvent in the reaction with 1, in contrast NBS was ineffective in trifluoroacetic acid. This renders 1 a superior reagent relative to NBS. In addition to aromatics, alkenes, ketones and esters were also brominated with 1. Diethyl malonate was brominated with 1 and then subjected to a Bingel reaction with NaH to afford the desired methanofullerene in reasonable yield. 相似文献
26.
Tozuka Z Kaneko H Shiraga T Mitani Y Beppu M Terashita S Kawamura A Kagayama A 《Journal of mass spectrometry : JMS》2003,38(8):793-808
Triple-stage quadrupole (TSQ) electrospray ionization (ESI) tandem mass spectrometry (MS/MS) and ion trap ESI-MS/MS can be used to cleave protonated molecules to produce carbocations and neutral molecules in the positive ion mode. Dissociation products which correspond to protonated forms of neutral fragment molecules can also be trapped and detected. These protonated molecules in turn can cleave via carbocation cleavage, ipso cleavage, onium cleavage or McLafferty or related rearrangements. One can elucidate the structures of metabolites from the differences in m/z ratios of the fragments arising from the original drug compound and its metabolite. This strategy for structural elucidation is further facilitated by estimates of the reactivity of drugs with oxygen diradicals involved in cytochrome P-450 cycles. 相似文献
27.
Soh N Imato T Kawamura K Maeda M Katayama Y 《Chemical communications (Cambridge, England)》2002,(22):2650-2651
A novel fluorescent probe, which could be the first example of a ratiometric molecular probe for direct monitoring of NO production, has been developed using a 'spin-exchange' mechanism. 相似文献
28.
Norio Manabe Kenichi Kawamura Masanao Ishikawa Shoutarou Suzuki Boping Liu Minoru Terano Hisayuki Nakatani 《Polymer Testing》2005,24(8):994-997
In this study, a novel potentiometric titration of hydroperoxide in degraded polypropylene (PP) is proposed. This titration is quite sensitive compared with the conventional ones such as UV and manual titrations, and its detection limit was about 2 meq/kg. The sensitivity was equal to that of molecular weight measurement by GPC for the degraded PP and, in addition, the volatilization behavior of the hydroperoxide could be detected. This titration was found to be very effective for the determination of PP degradation. 相似文献
29.
3-Phenyl-2-isoxazoline (1) was irradiated to give 4-phenyl-2-oxazoline (3), β-aminoaldehyde (14) and benzonitrile from its π-π* singlet excited state. Several related derivatives afforded similar photoproducts on irradiation. The quantum yields of the photoreactions were dependent on the magnitudes of the singlet energies of the 2-isoxazolines. p-Cyanophenyl-2-isoxazoline (1c) formed a one-to-one photoadduct (22) with benzene. 相似文献
30.
A spectrophotometric determination method for nM levels of Pb(II) has been developed using a stopped-flow spectrophotometer
with cationic water-soluble porphyrin. The stopped-flow spectrophotometer allows the monitoring of the incorporation reaction
of the Pb(II) ion into 5,10,15,20-terakis(1-methylpyridinium-4-yl)porphine (TMPYP) within a narrow time window (2.5 s) at
pH 10.5–12.0 before the Pb-TMPYP complex is replaced with other foreign metal ions, since usually the Pb-TMPYP complex is
very labile and readily replaced with other metal ions. This improved the selectivity of Pb(II) determination as compared
to the conventional spectrophotometric determination of Pb(II) using water-soluble porphyrins. 相似文献