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71.
The behavior of proton transfer facilitated by a novel thiazole derivative, N-methyl-4-(4-phenoxyphenyl)thiazol-2-amine (MPPT),
across the water/1,2-dichloroethane (1,2-DCE) interface was investigated electrochemically. The ionic partition diagram for
MPPT was obtained from interpretation of the cyclic voltammograms. The apparent partition coefficient of MPPT was evaluated
by the shaking-flask method under experimental conditions, while that for the protonated form of MPPT was calculated from
its transfer potential obtained from the ionic partition diagram. It was suggested that the mechanism for transfer of MPPT
across the water/1,2-DCE) interface depends on the pH of the aqueous phase. The parameters of the facilitated proton transfer
across the water/1,2-DCE interface were evaluated as a quantitative measure of its lipophilicity. 相似文献
72.
S. R. Garaeva Ahmet Alper Aydin Adnan Aydin Bahattin Yalçin P. A. Fatullaeva A. A. Medzhidov 《Russian Journal of Applied Chemistry》2010,83(1):97-101
Structure of products formed in polyethylene oxidation by nitric acid was studied by NMR, IR, and electronic absorption spectroscopies
and derivatography. 相似文献
73.
Ahmet Yildirim 《Meccanica》2010,45(1):1-6
He’s modified Lindstedt-Poincaré method is applied to nonlinear oscillatiors with fractional powers. Comparison of the obtained
results with exact solutions provides confirmation for the validity of He’s modified Lindstedt-Poincaré method. 相似文献
74.
75.
Mattson M Alkhazov G Atamantchouk AG Balatz MY Bondar NF Cooper PS Dauwe LJ Davidenko GV Dersch U Dolgolenko AG Dzyubenko GB Edelstein R Emediato L Endler AM Engelfried J Eschrich I Escobar CO Evdokimov AV Filimonov IS Garcia FG Gaspero M Giller I Golovtsov VL Gouffon P Gülmez E Kangling H Iori M Jun SY Kaya M Kilmer J Kim VT Kochenda LM Konorov I Kozhevnikov AP Krivshich AG Krüger H Kubantsev MA Kubarovsky VP Kulyavtsev AI Kuropatkin NP Kurshetsov VF Kushnirenko A Kwan S Lach J Lamberto A 《Physical review letters》2002,89(11):112001
We observe a signal for the doubly charmed baryon Xi(+)(cc) in the charged decay mode Xi(+)(cc)-->Lambda(+)(c)K-pi(+) in data from SELEX, the charm hadroproduction experiment at Fermilab. We observe an excess of 15.9 events over an expected background of 6.1+/-0.5 events, a statistical significance of 6.3sigma. The observed mass of this state is 3519+/-1 MeV/c(2). The Gaussian mass width of this state is 3 MeV/c(2), consistent with resolution; its lifetime is less than 33 fs at 90% confidence. 相似文献
76.
Kiyokazu Fuke Koji Kaya Takashi Kajiwara Saburo Nagakura 《Journal of Molecular Spectroscopy》1976,63(1):98-107
The electronic absorption spectra of perylene crystals in the α- and β-forms were measured by the normal incidence reflection method in the spectral region from 20 000 to 60 000 cm?1. From the absorption spectrum polarized perpendicular to [10] axis of the α-form crystal, the bands around 24 000 cm?1 were determined to be polarized along the long molecular axis. Two strong bands with different polarizations were observed around 50 000 cm?1 for each of the α- and β-perylene crystals and were assigned to the transitions to the 1B2u and 1B3u states. The observed polarized absorption spectra as a whole were consistent with the theoretical results by Hummel and Ruedenberg and the reflection method was found to be suitable to the polarized absorption measurement of strong bands of crystals. The observed factor-group splittings were compared with the theoretical values, the oriented gas model being found to be applicable to the β-form crystal. 相似文献
77.
Gören AC Bilsel G Bilsel M Yenisoy-Karaka S Karaka D 《Journal of chromatography. A》2004,1057(1-2):237-239
Atropine and obidoxime in a parenteral injection device are determined by simple HPLC method simultaneously without any pretreatment at 228 nm. The relative standard deviations (R.S.D.) were below 1.6% for the compounds. The correlation coefficient was greater than 0.999 for both compounds in the calibration range. The recoveries at 5 mg/L concentration averaged as 95% for atropine and 102% for obidoxime. The uncertainty of the measurements for atropine and obidoxime was 2.8% and 2.4%, respectively. 相似文献
78.
Ahmet Tekcan 《Results in Mathematics》2004,46(1-2):146-163
The number of representation of positive integers by quadratic forms $ F_{1}=x_{1}^{2}+3x_{1}x_{2}+8x_{2}^{2} $ and $ G_{1}=2x_{1}^{2}+3x_{1}x_{2}+4x_{2}^{2} $ of discriminant —23 are given. Moreover, a basis for the cusp form space S 4(Γ0(23), 1) are constructed. Furthermore, formulas for the representation of positive integers by direct sum of copies of F 1 and G 1, i.e. formulas for $ r(n; F_{4}), r(n; G_{4}), r(n; F_{3} \oplus G_{1}), r(n; F_{2} \oplus G_{2}), {\rm and}\ r(n; F_{1} \oplus G_{3}) $ , are derived using the elements of the space S 4(Γ(23), 1). 相似文献
79.
Firat AK Karakaş HM Yakinci C Altinok T Alkan A Biçak U 《Magnetic resonance imaging》2004,22(9):1329-1332
Acute disseminated encephalomyelitis (ADEM) is an immune-mediated demyelinating disorder usually encountered in children or adolescents and characterized by multifocal neurological deficits of rapid onset. Typical target areas of demyelination include the corona radiata, centrum semiovale, periventricular white matter, cerebellar peduncles and brainstem. Involvement of deep gray matter nuclei is also frequent. We report a 6-year-old boy with ADEM who had only brainstem involvement. Serial magnetic resonance images representing the stage of disease and response to steroid treatment are presented. 相似文献
80.
Anion photoelectron spectroscopy of acetonitrile cluster anions, (CH3CN)(-)(n) (n=10-100), successfully demonstrates the competitive coexistence of two different anionic species: a solvated electron and a solvent-bound valence anion. The distinctly different nature of these anions is revealed by hole-burning-type photoelectron spectroscopy and relative photodetachment cross section measurements. This unusual coexistence is attributed to the closely lying nature of their anionic states at just the number of solvent molecules sufficient to almost complete the first solvation layer. 相似文献