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561.
Jamnik A 《The journal of physical chemistry. B》2007,111(14):3674-3684
Grand canonical Monte Carlo simulation is used to study the adsorption of a binary sticky hard-sphere fluid mixture in planar pores. The wall-component 1 and wall-component 2 contact densities are determined to calculate the pressure as a function of the composition of the mixture and the separation between the walls. From these data dependence of the solvation force between the plates on pore width is estimated. The simulation results are compared with the predictions of the Percus-Yevick approximation for planar pores. The density profiles of particular components show interesting shapes stemming from the interplay between the steric effects and the competitive adhesion among all possible species pairs. It is shown that narrowing of the pore causes selective partitioning of individual components of the mixture between the bulk phase and the interior of the pore. The agreement between the two methods is better at wider pores and for the component comprised of weakly adhesive particles. 相似文献
562.
Ulrike Grossner Jens S. Christensen Bengt G. Svensson Andrej Yu. Kuznetsov 《Superlattices and Microstructures》2007,42(1-6):294
In order to obtain p-type ZnO, the incorporation of group-V elements on oxygen sites has received lots of attention. Recently, the implantation of Sb+ ions into ZnO has been shown to lead to reduced n-type conduction. However, a compensating effect due to implantation damage could not be ruled out. Therefore, single-crystal ZnO has been hydrothermally grown with additional Sb2O3, Sb2O5, and K(SbO)C4H4O6 in the solution. Schottky barrier contacts have been deposited onto the () face. Capacitance–voltage measurements and thermal admittance spectroscopy have been used for electrical characterization, and secondary ion mass spectrometry was used to measure the Sb content in the samples. Clearly, all samples exhibited n-type conduction. A competition between the incorporation of oxygen and antimony is suggested. 相似文献
563.
Fidanchevski Emilija Angjusheva Biljana Jovanov Vojo Murtanovski Pece Vladiceska Ljubica Aluloska Nikolina Stamatovska Nikolic Jelena Krneta Ipavec Andrej Šter Katarina Mrak Maruša Dolenec Sabina 《Journal of Radioanalytical and Nuclear Chemistry》2021,330(3):685-694
Journal of Radioanalytical and Nuclear Chemistry - Huge quantities of fly ash and bottom ash are generated from thermal power plants and it presents great concern for country, mainly due... 相似文献
564.
Physics of the Solid State - The computer simulation methods have been applied to calculate structure and energy of symmetric tilt grain boundaries (GB) with the misorientation axes [110] and... 相似文献
565.
Andrej A. Konʼkov 《Journal of Mathematical Analysis and Applications》2012,388(1):102-124
We obtain estimates for non-negative solutions of quasilinear elliptic inequalities with the lowest terms. 相似文献
566.
Bona Andrej; Bucataru Ioan; Slawinski Michael A. 《The Quarterly Journal of Mechanics and Applied Mathematics》2007,60(2):73-84
We show that, in general, wavefronts are more symmetric thanthe medium in which they propagate. This means that we cannotdetermine the symmetries of the medium based solely on the symmetriesof the wavefronts. However, we show that we can determine thesymmetries of the medium from the symmetries of wavefronts andpolarizations together. 相似文献
567.
Nicolas G. Martinelli Yoann Olivier Dr. Stavros Athanasopoulos Dr. Mari‐Carmen Ruiz Delgado Dr. Kathryn R. Pigg Demétrio A. da Silva Filho Dr. Roel S. Sánchez‐Carrera Dr. Elisabetta Venuti Raffaele G. Della Valle Prof. Jean‐Luc Brédas Prof. David Beljonne Dr. Jérôme Cornil Dr. 《Chemphyschem》2009,10(13):2265-2273
We have performed classical molecular dynamics simulations and quantum‐chemical calculations on molecular crystals of anthracene and perfluoropentacene. Our goal is to characterize the amplitudes of the room‐temperature molecular displacements and the corresponding thermal fluctuations in electronic transfer integrals, which constitute a key parameter for charge transport in organic semiconductors. Our calculations show that the thermal fluctuations lead to Gaussian‐like distributions of the transfer integrals centered around the values obtained for the equilibrium crystal geometry. The calculated distributions have been plugged into Monte‐Carlo simulations of hopping transport, which show that lattice vibrations impact charge transport properties to various degrees depending on the actual crystal structure. 相似文献
568.
Mono‐ and poly‐adenosine diphosphate (ADP)‐ribosylation are common post‐translational modifications incorporated by sequence‐specific enzymes at, predominantly, arginine, asparagine, glutamic acid or aspartic acid residues, whereas non‐enzymatic ADP‐ribosylation (glycation) modifies lysine and cysteine residues. These glycated proteins and peptides (Amadori‐compounds) are commonly found in organisms, but have so far not been investigated to any great degree. In this study, we have analyzed their fragmentation characteristics using different mass spectrometry (MS) techniques. In matrix‐assisted laser desorption/ionization (MALDI)‐MS, the ADP‐ribosyl group was cleaved, almost completely, at the pyrophosphate bond by in‐source decay. In contrast, this cleavage was very weak in electrospray ionization (ESI)‐MS. The same fragmentation site also dominated the MALDI‐PSD (post‐source decay) and ESI‐CID (collision‐induced dissociation) mass spectra. The remaining phospho‐ribosyl group (formed by the loss of adenosine monophosphate) was stable, providing a direct and reliable identification of the modification site via the b‐ and y‐ion series. Cleavage of the ADP‐ribose pyrophosphate bond under CID conditions gives access to both neutral loss (347.10 u) and precursor‐ion scans (m/z 348.08), and thereby permits the identification of ADP‐ribosylated peptides in complex mixtures with high sensitivity and specificity. With electron transfer dissociation (ETD), the ADP‐ribosyl group was stable, providing ADP‐ribosylated c‐ and z‐ions, and thus allowing reliable sequence analyses. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
569.
Jelka Šuštar-Vozlič Katja Rostohar Andrej Blejec Petra Kozjak Zoran Čergan Vladimir Meglič 《Analytical and bioanalytical chemistry》2010,396(6):2031-2041
In order to comply with the European Union regulatory threshold for the adventitious presence of genetically modified organisms
(GMOs) in food and feed, it is important to trace GMOs from the field. Appropriate sampling methods are needed to accurately
predict the presence of GMOs at the field level. A 2-year field experiment with two maize varieties differing in kernel colour
was conducted in Slovenia. Based on the results of data mining analyses and modelling, it was concluded that spatial relations
between the donor and receptor field were the most important factors influencing the distribution of outcrossing rate (OCR)
in the field. The approach for estimation fitting function parameters in the receptor (non-GM) field at two distances from
the donor (GM) field (10 and 25 m) for estimation of the OCR (GMO content) in the whole receptor field was developed. Different
sampling schemes were tested; a systematic random scheme in rows was proposed to be applied for sampling at the two distances
for the estimation of fitting function parameters for determination of OCR. The sampling approach had already been validated
with some other OCR data and was practically applied in the 2009 harvest in Poland. The developed approach can be used for
determination of the GMO presence at the field level and for making appropriate labelling decisions. The importance of this
approach lies in its possibility to also address other threshold levels beside the currently prescribed labelling threshold
of 0.9% for food and feed. 相似文献
570.
Vinzenz Handrick Thomas Vogt Andrej Frolov 《Analytical and bioanalytical chemistry》2010,398(7-8):2789-2801
Phenylpropanoid polyamine conjugates are widespread in plant species. Their presence has been established in seeds, flower buds, and pollen grains. A biosynthetic pathway proposed for hydroxycinnamoyl spermidine conjugates has been suggested for the model plant Arabidopsis thaliana with a central acyl transfer reaction performed by a BAHD-like hydroxycinnamoyl transferase. A detailed liquid chromatography (LC)–electrospray ionization–mass spectrometry- and tandem-mass-spectrometry (MS/MS)-based survey of wild-type and spermidine hydroxycinnamoyl transferase (SHT) mutants identified more than 30 different bis- and tris-substituted spermidine conjugates, five of which were glycosylated, in the methanol-soluble fraction of the pollen exine. On the basis of characterized fragmentation patterns, a high-throughput LC–MS/MS method for highly sensitive HCAA relative quantification (targeted profiling) was developed. Only minor qualitative and quantitative differences in the pattern of bis-acyl spermidine conjugates in the SHT mutant compared to wild-type plants provide strong evidence for the presence of multiple BAHD-like acyl transferases and suggest a much more complex array of enzymatic steps in the biosynthesis of these conjugates than previously anticipated. 相似文献