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141.
We present a method for constructing shape-preserving C
3 interpolants in R
3. The resulting curve is obtained by adding a polynomial perturbation of high degree to a curve which is shape-preserving but not sufficiently smooth. The degree of the perturbed curve is selected in order to maintain the shape properties of the basic curve. 相似文献
142.
Giovanna Baron Giulio Ferrario Cristina Marinello Marina Carini Paolo Morazzoni Giancarlo Aldini 《Molecules (Basel, Switzerland)》2021,26(18)
A fully-detailed LC-MS qualitative profiling of red grape skin, extracted with a mixture of ethanol and water (70:30 v:v) has permitted the identification of 65 compounds which can be classified into the following chemical classes: organic and phenolic acids (14 compounds), stilbenoids (1 compound), flavanols (21 compounds), flavonols (15 compounds) and anthocyanins (14 compounds). The extraction yield obtained with water at different temperatures (100 °C, 70 °C, room temperature) was then evaluated and the overall polyphenol content indicates that EtOH:H2O solvent is the most efficient and selective for polyphenol extraction. However, by analyzing the recovery yield of each single polyphenol, we found that water extraction under heating conditions is effective (extraction yield similar or even better in respect to the binary solvent) for some polyphenolic classes, such as hydrophilic procyanidins, phenolic acids, flavonol glucosides and stilbenoids. However, according to their lipophilic character, a poor yield was found for the most lipophilic components, such as flavonol aglycones, and in general for anthocyanins. The radical scavenging activity was in accordance with the polyphenol content, and hence, much higher for the extract obtained with the binary solvent in respect to water extraction. All the tested extracts were found to have an anti-inflammatory activity in the R3/1 cell line with NF-kb reporter challenged with 0.01 µg/mL of IL-1α, in a 1 to 250 µg/mL concentration range. An intriguing result was that the EtOH:H2O extract was found to be superimposable with that obtained using water at 100 °C despite the lower polyphenol content. Taken together, the results show the bioactive potentialities of grape skin extracts and the possibility to exploit this rich industrial waste. Water extraction carried out by heating is an easy, low-cost and environmentally friendly extraction method for some polyphenol classes and may have great potential for extracts with anti-inflammatory activities. 相似文献
143.
Riccardo Salvati Manni 《manuscripta mathematica》2000,101(2):267-269
In this paper we prove the existence of cusp forms relative to the full modular group whose genus is equal to the weight.
These cusp forms are linear combination of theta series.
Received: 26 July 1999 / Revised version: 16 September 1999 相似文献
144.
S. Colacicchi V. Carnicelli G. Gualtieri A. Di Giulio 《Research on Chemical Intermediates》2000,26(9):885-896
EPR and UV spectroscopy were used to investigate the efficiency of ascorbic acid in reducing Fremy’s salt. Our data indicates
that the first proton electron transfer from ascorbate occurs within the mixing time. Even after the disappearance of the
UV signal of the ascorbate, EPR measurements showed that the reaction goes forward, indicating a biphasic redox process. The
slower time-course of this second phase was related to the initial concentrations of the reductant. Experiments performed
at four different pH values demonstrated that the reduction was a function of the bulk solution pH. At the lower pH, after
a fast initial reduction, the Fremy’s salt EPR signal remained constant, while at physiological or higher pH a further reduction
was found.
The reaction rates demonstrate that the reducing power of ascorbic acid towards Fremy’s salt strongly depends on its dissociation
state. 相似文献
145.
Salvatore Galati Stefano Sainas Marta Giorgis Donatella Boschi Marco L. Lolli Gabriella Ortore Giulio Poli Tiziano Tuccinardi 《Molecules (Basel, Switzerland)》2022,27(12)
Human dihydroorotate dehydrogenase (hDHODH) is an enzyme belonging to a flavin mononucleotide (FMN)-dependent family involved in de novo pyrimidine biosynthesis, a key biological pathway for highly proliferating cancer cells and pathogens. In fact, hDHODH proved to be a promising therapeutic target for the treatment of acute myelogenous leukemia, multiple myeloma, and viral and bacterial infections; therefore, the identification of novel hDHODH ligands represents a hot topic in medicinal chemistry. In this work, we reported a virtual screening study for the identification of new promising hDHODH inhibitors. A pharmacophore-based approach combined with a consensus docking analysis and molecular dynamics simulations was applied to screen a large database of commercial compounds. The whole virtual screening protocol allowed for the identification of a novel compound that is endowed with promising inhibitory activity against hDHODH and is structurally different from known ligands. These results validated the reliability of the in silico workflow and provided a valuable starting point for hit-to-lead and future lead optimization studies aimed at the development of new potent hDHODH inhibitors. 相似文献
146.
Mattia Russo Kirsty E. McGhee Tersilla Virgili David G. Lidzey Giulio Cerullo Margherita Maiuri 《Molecules (Basel, Switzerland)》2022,27(20)
Molecular dyes are finding more and more applications in photonics and quantum technologies, such as polaritonic optical microcavities, organic quantum batteries and single-photon emitters for quantum sensing and metrology. For all these applications, it is of crucial importance to characterize the dephasing mechanisms. In this work we use two-dimensional electronic spectroscopy (2DES) to study the temperature dependent dephasing processes in the prototypical organic dye Lumogen-F orange. We model the 2DES maps using the Bloch equations for a two-level system and obtain a dephasing time T2 = 53 fs at room temperature, which increases to T2 = 94 fs at 86 K. Furthermore, spectral diffusion processes are observed and modeled by a combination of underdamped and overdamped Brownian oscillators. Our results provide useful design parameters for advanced optoelectronic and photonic devices incorporating dye molecules. 相似文献
147.
Simone Carradori Marialuigia Fantacuzzi Alessandra Ammazzalorso Andrea Angeli Barbara De Filippis Salvatore Galati Anl Petzer Jacobus P. Petzer Giulio Poli Tiziano Tuccinardi Mariangela Agamennone Claudiu T. Supuran 《Molecules (Basel, Switzerland)》2022,27(22)
Neurodegenerative diseases (NDs) are described as multifactorial and progressive syndromes with compromised cognitive and behavioral functions. The multi-target-directed ligand (MTDL) strategy is a promising paradigm in drug discovery, potentially leading to new opportunities to manage such complex diseases. Here, we studied the dual ability of a set of resveratrol (RSV) analogs to inhibit two important targets involved in neurodegeneration. The stilbenols 1–9 were tested as inhibitors of the human monoamine oxidases (MAOs) and carbonic anhydrases (CAs). The studied compounds displayed moderate to excellent in vitro enzyme inhibitory activity against both enzymes at micromolar/nanomolar concentrations. Among them, the best compound 4 displayed potent and selective inhibition against the MAO-B isoform (IC50 MAO-A 0.43 µM vs. IC50 MAO-B 0.01 µM) with respect to the parent compound resveratrol (IC50 MAO-A 13.5 µM vs. IC50 MAO-B > 100 µM). It also demonstrated a selective inhibition activity against hCA VII (KI 0.7 µM vs. KI 4.3 µM for RSV). To evaluate the plausible binding mode of 1–9 within the two enzymes, molecular docking and dynamics studies were performed, revealing specific and significant interactions in the active sites of both targets. The new compounds are of pharmacological interest in view of their considerably reduced toxicity previously observed, their physicochemical and pharmacokinetic profiles, and their dual inhibitory ability. Compound 4 is noteworthy as a promising lead in the development of MAO and CA inhibitors with therapeutic potential in neuroprotection. 相似文献
148.
Baptiste Demoulin Margherita Maiuri Tetyana Berbasova Prof. James H. Geiger Prof. Babak Borhan Prof. Marco Garavelli Prof. Giulio Cerullo Prof. Ivan Rivalta 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(66):16389-16400
Artificial biomimetic chromophore-protein complexes inspired by natural visual pigments can feature color tunability across the full visible spectrum. However, control of excited state dynamics of the retinal chromophore, which is of paramount importance for technological applications, is lacking due to its complex and subtle photophysics/photochemistry. Here, ultrafast transient absorption spectroscopy and quantum mechanics/molecular mechanics simulations are combined for the study of highly tunable rhodopsin mimics, as compared to retinal chromophores in solution. Conical intersections and transient fluorescent intermediates are identified with atomistic resolution, providing unambiguous assignment of their ultrafast excited state absorption features. The results point out that the electrostatic environment of the chromophore, modified by protein point mutations, affects its excited state properties allowing control of its photophysics with same power of chemical modifications of the chromophore. The complex nature of such fine control is a fundamental knowledge for the design of bio-mimetic opto-electronic and photonic devices. 相似文献
149.
150.
Giulio Supino 《Annali di Matematica Pura ed Applicata》1931,9(1):91-119
Sunto L'A, studia in questa Memoria la distribuzione delle tensioni interne in un solido elastico convesso quando gli spostamenti,
dati in superficie, sono diversi da zero solo in una piccola zona. Nei campi a due dimensioni il risultato è esteso al caso
in cui sul contorno siano date le forze; si giunge così ad una dimostrazione del principio del De Saint Venant. 相似文献