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101.
Elisa Moretti Manuela Aversa Alberto Scrivanti Loretta Storaro Aldo Talon Riccardo Marin Juan Antonio Cecilia Enrique Rodríguez-Castellón Stefano Polizzi 《Chemical Papers》2016,70(2):218-230
A new synthesised triphenylamine-based dye having a branched structure with one OH-ending branch able to interact with the surface hydroxyl moieties of mesoporous TiO2 is reported. Optical properties of the dye-titania hybrid material are presented and the higher efficiency of the dye on pure anatase TiO2 compared to the commercial Degussa P25, which contains a rutile phase component, is confirmed. The optical and chemical properties of the dye make it a promising candidate as a metal-free dye for DSSCs or as a host for a variety of transition or main group metal ions for different applications. 相似文献
102.
A. Trapananti T. Eisenmann G. Giuli F. Mueller A. Moretti S. Passerini D. Bresser 《Materials Today Chemistry》2021
The precise determination of de-/lithiation mechanisms in alternative lithium-ion battery electrode materials is crucial for their potential future success, but quite challenging — e.g., due to the occurrence of multiple crystalline and (frequently) amorphous phases. Herein, we report an in-depth ex situ/operando characterization of (carbon-coated) Fe- and Co-doped zinc oxide anodes via X-ray absorption spectroscopy to probe the oxidation state and local structural environment of the different metals upon de-/lithiation. The results provide fundamental insights into the mechanism of the conversion and alloying reaction taking place for these two active materials. In addition, this comparative investigation allows for an evaluation of the impact of isovalent (Co2+) and aliovalent (Fe3+) doping on the lithiation mechanism, having an impact on the initial lithiation kinetics, while both dopants generally enable a greatly increased re-oxidation of zinc compared to pure zinc oxide and, thus, a more reversible conversion reaction. 相似文献
103.
Gussoni M Greco F Vezzoli A Paleari MA Moretti VM Lanza B Zetta L 《Magnetic resonance imaging》2007,25(1):117-128
By combining NMR relaxation spectroscopy and magnetic resonance imaging techniques, unsalted (us) and salted (s) caviar (Acipenser transmontanus) oocytes were characterized over a storage period of up to 90 days. The aging and the salting effects on the two major cell constituents, water and lipids, were separately assessed. T1 and T2 decays were interpreted by assuming a two-site exchange model. At Day 0, two water compartments that were not in fast exchange were identified by the T1 relaxation measurements on the us oocytes. In the s samples, T1 decay was monoexponential. During the time of storage, an increment of the free water amount was found for the us oocytes, ascribed to an increased metabolism. T1 and T2 of the s oocytes shortened as a consequence of the osmotic stress produced by salting. Selective images showed the presence of water endowed with different regional mobility that severely changed during the storage. Lipid T1 relaxation decays collected on us and s samples were found to be biexponential, and the T1 values lengthened during storage. In us and s oocytes, the increased lipid mobility with the storage was ascribed to lipolysis. Selective images of us samples showed lipids that were confined to the cytoplasm for up to 60 days of storage. 相似文献
104.
Thomas Geiger Simon Schundelmeier Thorsten Hummel Dr. Markus Ströbele Dr. Wolfgang Leis Prof. Dr. Michael Seitz Clemens Zeiser Luca Moretti Dr. Margherita Maiuri Prof. Dr. Giulio Cerullo Jun.-Prof. Dr. Katharina Broch Jörn Vahland Prof. Dr. Karl Leo Dr. Cäcilia Maichle-Mössmer Prof. Dr. Bernd Speiser Prof. Dr. Holger F. Bettinger 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(15):3420-3434
The properties as well as solid-state structures, singlet fission, and organic field-effect transistor (OFET) performance of three tetrafluoropentacenes (1,4,8,11: 10 , 1,4,9,10: 11 , 2,3,9,10: 12 ) are compared herein. The novel compounds 10 and 11 were synthesized in high purity from the corresponding 6,13-etheno-bridged precursors by reaction with dimethyl 1,2,4,5-tetrazine-3,6-dicarboxylate at elevated temperatures. Although most of the molecular properties of the compounds are similar, their chemical reactivity and crystal structures differ considerably. Isomer 10 undergoes the orbital symmetry forbidden thermal [4+4] dimerization, whereas 11 and 12 are much less reactive. The isomers 11 and 12 crystallize in a herringbone motif, but 10 prefers π–π stacking. Although the energy of the first electric dipole-allowed optical transition varies only within 370 cm−1 (0.05 eV) for the neutral compounds, this amounts to roughly 1600 cm−1 (0.20 eV) for radical cations and 1300 cm−1 (0.16 eV) for dications. Transient spectroscopy of films of 11 and 12 reveals singlet-fission time constants (91±11, 73±3 fs, respectively) that are shorter than for pentacene (112±9 fs). OFET devices constructed from 11 and 12 show close to ideal thin-film transistor (TFT) characteristics with electron mobilities of 2×10−3 and 6×10−2 cm2 V−1 s−1, respectively. 相似文献
105.
V. Mussi A. Cricenti B. Jacquier T. Marolo R. M. Montereali P. Moretti 《辐射效应与固体损伤》2013,168(1-6):181-184
The measured room-temperature absorption spectra of LiF crystals implanted with 1.5 MeV He? ions at different ion doses are presented. The application of a theoretical model allowed us to give an estimation of the band intensities associated with various kinds of electronic defects and to study their dependence on the ion dose. The model also considers the contribution due to nanometric lithium colloids, whose formation starts in the dose range at which the production of colour centres saturates. 相似文献
106.
Simone?MorpurgoEmail author Giuliano?Moretti Mario?Bossa 《Theoretical chemistry accounts》2012,131(3):1180
DFT calculations on the coordination of Cu+ to the framework oxygen atoms of Al-substituted ZSM-5 were performed by using combinations of different basis sets in order
to investigate the dependence of the results on the adopted computational level. With low-end basis sets, a large basis set
superposition error (BSSE) favors the coordination of Cu+ to three to four oxygen atoms of the framework, only two of which belong to the AlO4 tetrahedron corresponding to the investigated T-site. More extended basis sets considerably lower the BSSE and favor the
coordination of Cu+ to only two oxygen atoms of the AlO4 tetrahedron. Upon interaction with NO, the Cu+ ion is always coordinated by two oxygen atoms of the AlO4 tetrahedron, independently of the basis set adopted and of the coordination number before NO adsorption. The shift from three-
to twofold coordination caused by the Cu+–NO interaction requires a deformation energy that lowers the final adsorption energy. Such an effect is relevant with low-end
basis sets, whereas it is substantially absent with more extended basis sets, which favor the twofold coordination of Cu+ even before NO adsorption. As a result, high-end basis sets increase the NO interaction energy with respect to that calculated
by low-end basis sets, in agreement with experiments and suggesting a possible re-interpretation of the catalytic properties
of the investigated sites. Provided suitable scale factors are employed, the N–O stretching frequencies of adsorbed nitrogen
oxide calculated by sufficiently extended basis sets turned out in fair agreement with experimental findings. 相似文献
107.
Windows are the weakest part of a façade in terms of acoustic performance: the weighted sound insulation index (Rw), measured according to ISO 140-3, is the fundamental parameter to evaluate the façade acoustic insulation.The paper aims at developing an artificial neural network (ANN) model to estimate the Rw value of wooden windows based on a limited number of windows parameters; this is a new approach because acoustic phenomena are non-linear and affected by a plurality of factors and, therefore, usually investigated through experimentation.Data set is taken from experimental campaigns carried out at the Laboratory of Acoustics, University of Perugia. A multilayer feed-forward approach was chosen and the model was implemented in MATLAB. On the basis of the results obtained by means of a preliminary training and test campaign of several ANN architectures, five main parameters were selected as network inputs: window typology, frame and shutters thickness, number of gaskets, Rw of glazing; Rw value of the window is the network output. Different ANN configurations were trained and a root mean-square error less than 3% was obtained, comparable to measurement uncertainty.This approach allows to develop a model which, with input parameters varying within appropriate ranges, can easily estimate the acoustic performance of wooden windows without experimental campaign on prototypes, saving both money and time. If the training data set is large enough, the presented approach could be very useful for design and optimization of acoustic performance of new products. 相似文献
108.
Matteo Moretti Francesca Freni Claudia Carelli Carlo Previder Pierangela Grignani Claudia Vignali Maria Cobo-Golpe Luca Morini 《Molecules (Basel, Switzerland)》2021,26(17)
Dried urine spots (DUS) represent a potential alternative sample storage for forensic toxicological analysis. The aim of the current study was to develop and validate a liquid chromatographic tandem mass spectrometric procedure for the detection and quantitative determination of cannabinoids and metabolites in DUS. A two-step extraction was performed on DUS and urine samples. An LC-MS/MS system was operated in multiple reaction monitoring and positive polarization mode. The method was checked for sensitivity, specificity, linearity, accuracy, precision, recovery, matrix effects and carryover. The method was applied to 70 urine samples collected from healthy volunteers and drug addicts undergoing withdrawal treatment. The method was successfully developed for DUS. LODs lower than 2.0 ng/mL were obtained for all the monitored substances. All the validation parameters fulfilled the acceptance criteria either for DUS or urine. Among the real samples, 45 cases provided positive results for at least one compound. A good quali-quantitative agreement was obtained between DUS and urine. A good stability of THC, THCCOOH and THCCOOH-gluc was observed after a 24 h storage, in contrast to previously published results. DUS seems to provide a good alternative storage condition for urine that should be checked for the presence of cannabinoids and metabolites. 相似文献
109.
S. Hesselbach S. Moretti J. Rathsman A. Sopczak 《The European Physical Journal C - Particles and Fields》2008,53(2):311-327
We report on detailed Monte Carlo comparisons of selection variables to separate tbH± signal events from the standard model tt̄ background using an iterative discriminant analysis (IDA) method. While kinematic
differences exist between the two processes whenever , the exploration of the spin difference between the charged Higgs and the W± gauge boson becomes crucial in the particularly challenging case of near degeneracy of the charged Higgs boson mass with
the W± mass. The TAUOLA package is used to decay the tau leptons emerging from the charged Higgs and W± boson decays taking the spin difference properly into account. We demonstrate that, even if the individual selection variables
have limited discriminant power, the IDA method achieves a significant separation between the expected signal and background.
For both Tevatron and LHC energies, the impact of the spin effects and H± mass on the separation of signal and background has been studied quantitatively. The effect of a hard transverse momentum
cut to remove QCD background has been studied and it is found that the spin effects remain important. The separation is expressed
in purity versus efficiency curves. The study is performed for charged Higgs boson masses between the W± mass and near the top mass. 相似文献
110.