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Summary The strong-motion accelerograms written by moderate and strong earthquakes occurring in Central Italy in recent years have
been used to estimate physical quantities characterizing the spectrum of motion in the band of engineering interest (0.1 Hz≲f≲20 Hz). The source, propagation and site response parameters obtained in these analyses have therefore been employed to check
if theoretical models may be used to correctly predict the trend of the peak values of seismic excitationvs. earthquake size in the areas investigated. For the selected data set, representative of a seismotectonic environment generating
earthquakes with prevalent normal faulting (up to a magnitudeM
l
∼7, at depths varying roughly from 5 to 15 km), the assumed spectral model allows successful statistical predictions showing
that specific site response is the main factor responsible for the large fluctuations often observed in the data behaviour,
at similar magnitudes and distances from focus.
Riassunto Gli accelerogrammi registrati in occasione di terremoti da moderati a forti nell'Italia Centrale negli ultimi anni sono stati utilizzati per la stima delle grandezze fisiche che caratterizzano lo spettro del moto nella banda di interesse ingegneristico (0.1 Hz≲f≲20 Hz). La parametrizzazione ottenuta per descrivere, mediamente, i meccanismi della sorgente, della propagazione e degli effetti di sito è stata quindi usata per verificare se i modelli teorici possono essere utilmente usati per prevedere gli andamenti dei valori di picco del moto in funzione dell'entità del terremoto. Per i dati selezionati, rappresentativi di un ambiente sismotettonico in grado di generare terremoti con meccanismi prevalentemente distensivi (fino ad una magnitudoM l ∼7, con profondità variabile all'incirca tra 5 e 15 km), il modello spettrale prescelto consente delle previsioni soddisfacenti da un punto di vista statistico, mostrando che la specifica risponsta dei siti è probabilmente il fattore che provoca le sensibili fluttuazioni spesso osservate per i valori di picco del moto, anche a parità di magnitudo e distanza dal fuoco.相似文献
44.
G. Saracco F. Geobaldo D. Mazza G. Baldi 《Journal of Thermal Analysis and Calorimetry》1999,56(3):1435-1442
A new method for the synthesis of fine catalyst powders is presented. Catalyst precursors are dissolved in an ethanol-water
mixture which is burned through a nozzle-type burner. As a result, catalyst powders are formed and removed from flue gases
through a filter. LaMnO3 catalysts for the catalytic combustion of methane have been prepared, characterised (TEM, XRD) and compared with a reference
manfacturing method (the citrates one) showing promising, though improvable, results.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
45.
46.
Edoardo Ballico 《Designs, Codes and Cryptography》2014,73(3):1023-1026
In this note we prove that every network code over \(\mathbb{F }_q\) may be realized taking some of the osculating spaces of a smooth projective curve. 相似文献
47.
Dr. Anil Reddy Marri Edoardo Marchini Dr. Valentin Diez Cabanes Dr. Roberto Argazzi Dr. Mariachiara Pastore Prof. Stefano Caramori Prof. Carlo Alberto Bignozzi Dr. Philippe C. Gros 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(65):16260-16269
A series of six new Fe(II)NHC-carboxylic sensitizers with their ancillary ligand decorated with functions of varied electronic properties have been designed with the aim to increase the metal-to- surface charge separation and light harvesting in iron-based dye-sensitized solar cells (DSSCs). ARM130 scored the highest efficiency ever reported for an iron-sensitized solar cell (1.83 %) using Mg2+ and NBu4I-based electrolyte and a thick 20 μm TiO2 anode. Computational modelling, transient absorption spectroscopy and electrochemical impedance spectroscopy (EIS) revealed that the electronic properties induced by the dimethoxyphenyl-substituted NHC ligand of ARM130 led to the best combination of electron injection yield and spectral sensitivity breadth. 相似文献
48.
K Bhaskaran-Nair J Brabec E Aprà HJ van Dam J Pittner K Kowalski 《The Journal of chemical physics》2012,137(9):094112
In this paper we discuss the performance of the non-iterative state-specific multireference coupled cluster (SS-MRCC) methods accounting for the effect of triply excited cluster amplitudes. The corrections to the Brillouin-Wigner and Mukherjee's MRCC models based on the manifold of singly and doubly excited cluster amplitudes (BW-MRCCSD and Mk-MRCCSD, respectively) are tested and compared with exact full configuration interaction results for small systems (H(2)O, N(2), and Be(3)). For the larger systems (naphthyne isomers) the BW-MRCC and Mk-MRCC methods with iterative singles, doubles, and non-iterative triples (BW-MRCCSD(T) and Mk-MRCCSD(T)) are compared against the results obtained with single reference coupled cluster methods. We also report on the parallel performance of the non-iterative implementations based on the use of processor groups. 相似文献
49.
Bacillus thuringiensis and recombinant Escherichia coli proteinaceous protoxins were subject to proteolysis and analyzed by capillary electrokinetic chromatography. Three resulting toxins (65 kDa) were baseline-resolved within 22 min using a 10 mM borate, pH 11 separation buffer consisting of 25 mM sodium dodecyl sulfate (SDS) and 30 mM phytic acid. The toxins displayed differential interactions with the SDS and phytic acid phases to effect their separation. The ion-pairing interaction between the analyte and phytic acid was also useful in preventing adsorption to the capillary walls and thus enhanced separation resolution and efficiency. The use of electrokinetic chromatography allows achievement of the separation in a significantly shorter time than conventional high-performance liquid chromatography (HPLC) using a diethylaminoethyl (DEAE) weak-anion exchanger. 相似文献
50.
Ivan Buslov Jeanne Becouse Simona Mazza Mickael Montandon‐Clerc Prof. Dr. Xile Hu 《Angewandte Chemie (International ed. in English)》2015,54(48):14523-14526
Chemoselective hydrosilylation of functionalized alkenes is difficult to achieve using base‐metal catalysts. Reported herein is that well‐defined bis(amino)amide nickel pincer complexes are efficient catalysts for anti‐Markovnikov hydrosilylation of terminal alkenes with turnover frequencies of up to 83 000 per hour and turnover numbers of up to 10 000. Alkenes containing amino, ester, amido, ketone, and formyl groups are selectively hydrosilylated. A slight modification of reaction conditions allows tandem isomerization/hydrosilylation reactions of internal alkenes using these nickel catalysts. 相似文献