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51.
52.
Hany Nasef Valerio Beni Veli C. Őzalp Ciara K. O’Sullivan 《Analytical and bioanalytical chemistry》2010,396(7):2565-2574
Cystic fibrosis is one of the most common genetically inherited diseases in northern Europe, with the DF508 mutation being
the most common, and among the Caucasian population being responsible for almost 70% of cases. In this work, we report on
the use of thermally modulated electrochemical impedance spectroscopy for the discrimination of the DF508 mutation from the
wild-type sequence. DNA probes (15 and 21 bases long) were immobilised on the surface of gold electrodes and the variation
of the charge-transfer resistance was monitored as a function of hybridisation. Two sets of targets were used in this work:
synthetic 15-mer sequences and two single-stranded synthetic analogues of PCR products 82 (mutant) and 85 (wild type) bases
long. Hybridisation with short targets resulted in very sequence specific charge-transfer-resistance variation with a discrimination
factor at room temperature between fully complementary and mismatched sequences of approximately fivefold. However, in the
case of the single-stranded synthetic PCR product analogues, a lower discrimination factor was recorded (1.5-fold). The effect
of temperature was investigated to improve discrimination and the use of a posthybridisation wash at elevated temperature
resulted in a fivefold improvement in the discrimination factor. Using an electrode array with probes immobilised against
each of the mutant and wild-type sequences, we achieved an unequivocal detection of the DF508 mutation. 相似文献
53.
Ab initio calculations on twenty van der Waals dimers of small polar molecules at the experimentally observed intermolecular separation R, using Hartree-Fock molecular moments, show that the minima in the electrostatic interaction expanded up to R−6 converges to angular structures which are close to those observed experimentally for such complexes. 相似文献
54.
Valerio Faraoni 《Annals of Physics》2005,317(2):366-382
We study the phase space of spatially homogeneous and isotropic cosmology in general scalar-tensor theories. A reduction to a two-dimensional phase space is performed when possible—in these situations the phase space is usually a two-dimensional curved surface embedded in a three-dimensional space and composed of two sheets attached to each other, possibly with complicated topology. The results obtained are independent of the choice of the coupling function of the theory and, in certain situations, also of the potential. 相似文献
55.
Biofunctionalization of Polyoxometalates with DNA Primers,Their Use in the Polymerase Chain Reaction (PCR) and Electrochemical Detection of PCR Products
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Dr. Ahmed M. Debela Dr. Mayreli Ortiz Dr. Valerio Beni Prof. Serge Thorimbert Dr. Denis Lesage Prof. Richard B. Cole Prof. Ciara K. O'Sullivan Prof. Bernold Hasenknopf 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(49):17721-17727
The bioconjugation of polyoxometalates (POMs), which are inorganic metal oxido clusters, to DNA strands to obtain functional labeled DNA primers and their potential use in electrochemical detection have been investigated. Activated monooxoacylated polyoxotungstates [SiW11O39{Sn(CH2)2CO}]8? and [P2W17O61{Sn(CH2)2CO}]6? have been used to link to a 5′‐NH2 terminated 21‐mer DNA forward primer through amide coupling. The functionalized primer was characterized by using a battery of techniques, including electrophoresis, mass spectrometry, as well as IR and Raman spectroscopy. The functionality of the POM‐labeled primers was demonstrated through hybridization with a surface‐immobilized probe. Finally, the labeled primers were successfully used in the polymerase chain reaction (PCR) and the PCR products were characterized by using electrophoresis. 相似文献
56.
Rio-Echevarria IM Tavano R Causin V Papini E Mancin F Moretto A 《Journal of the American Chemical Society》2011,133(1):8-11
The stabilizing action of C(α)-tetrasubstituted α-amino acids inserted into a sequence of short peptides allowed for the first time the preparation of water-soluble nanoparticles of different materials coated with a helix-structured undecapeptide. This peptide coating strongly favors nanoparticle uptake by human immune system cells. 相似文献
57.
Alberti A Fuochi P Guerra M Macciantelli D Torri G Valerio A Vismara E 《Organic & biomolecular chemistry》2011,9(9):3199-3204
Irradiation of a number of different sutures largely employed in the clinical practice with either high energy electrons or with γ-rays followed by quenching with glycidyl methacrylate (GMA) conveniently led to derivatization through a radical-based process. The radicals involved were detected by means of ESR spectroscopy and were characterized on the basis of their ESR spectral parameters which were also found to be consistent with the hfs constants predicted by DFT calculations. Evidence of the GMA derivatization of the sutures was obtained via(13)C CP-MAS NMR spectroscopy, while its extent was evaluated gravimetrically. 相似文献
58.
A simple base promoted intramolecular Michael initiated ring closure reaction of γ-hydroxyenone derived diphenyl phosphinates with 1,3-indandione, enabled the synthesis of novel activated cyclopropanes with homologated carbonyl moiety in good yield. Promising levels of enantioselectivity are achieved when using cinchona derivatives as promoters. 相似文献
59.
Conte P Mineo V Bubici S De Pasquale C Aboud F Maccotta A Planeta D Alonzo G 《Analytical and bioanalytical chemistry》2011,400(5):1443-1450
A number of pistachio oils were selected in order to test the efficacy of nuclear magnetic resonance relaxation dispersion (NMRD) technique in the evaluation of differences among oils (1) obtained from seeds subjected to different thermal desiccation processes, (2) retrieved from seeds belonging to the same cultivar grown in different geographical areas and (3) produced by using seed cultivars sampled in the same geographical region. NMRD measures relaxation rate values which are related to the dynamics of the chemical components of complex food systems. Results not only allowed to relate kinematic viscosity to relaxometry parameters but also were successful in the differentiation among the aforementioned oils. In fact, from the one hand, the larger the kinematic viscosity, the faster the rotational motions appeared as compared to the translational ones. On the other hand, relaxation rate curves (NMRD) varied according to the oxidative stresses and chemical composition of each sample. The present study showed for the first time that NMRD is a very promising technique for quick evaluations of pistachio oil quality without the need for time-consuming chemical manipulations. 相似文献
60.
Halfen DT Clouthier DJ Ziurys LM Lattanzi V McCarthy MC Thaddeus P Thorwirth S 《The Journal of chemical physics》2011,134(13):134302
The pure rotational spectrum of HPS, as well as its (34)S and D isotopologues, has been recorded at microwave, millimeter, and submillimeter wavelengths, the first observation of this molecule in the gas phase. The data were obtained using a combination of millimeter direct absorption, Fourier transform microwave (FTMW), and microwave-microwave double-resonance techniques, which cover the total frequency range from 15 to 419 GHz. Quantum chemical calculations at the B3LYP and CCSD(T) levels were also performed to aid in spectral identification. HPS was created in the direct absorption experiment from a mixture of elemental phosphorus, H(2)S, and Ar carrier gas; DPS was produced by adding D(2). In the FTMW study, these species were generated in a pulsed discharge nozzle from PH(3) and H(2)S or D(2)S, diluted in neon. The spectra recorded for HPS and its isotopologues exhibit clear asymmetric top patterns indicating bent structures; phosphorus hyperfine splittings were also observed in HPS, but not DPS. Analysis of the data yielded rotation, centrifugal distortion, and phosphorus nuclear spin-rotation parameters for the individual species. The r(m) ((1)) structure for HPS, calculated from the rotational constants, is r(H-P) = 1.438(1) A?, r(P-S) = 1.9320(1) A?, and θ(H-P-S) = 101.85(9)°. Empirically correcting for zero-point vibrational effects yields the geometry r(e)(H-P) = 1.4321(2) A?, r(e)(P-S) = 1.9287(1) A?, and θ(e)(H-P-S) = 101.78(1)°, in close agreement with the r(m) ((1)) structure. A small inertial defect was found for HPS indicating a relatively rigid molecule. Based on these data, the bonding in this species is best represented as H-P=S, similar to the first-row analog HNO, as well as HNS and HPO. Therefore, substitution of phosphorus and sulfur for nitrogen and oxygen does not result in a dramatic structural change. 相似文献