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41.
The joint action of two rectangular direct and constant fields (electric and magnetic) on molten potassium nitrate, produces local temperature variations in the Lorentz force direction. This thermal effect is studied as a function of the magneto-electric stress and also of the temperature of the molten electrolyte. The results are different depending on the initial thermal conditions; they are compared with the previous magneto-electric voltage measurements. 相似文献
42.
Dr. Maria L. Di Paolo Dr. Michael S. Christodoulou Dr. Alessandra M. Calogero Dr. Luca Pinzi Prof. Giulio Rastelli Prof. Daniele Passarella Prof. Graziella Cappelletti Prof. Lisa Dalla Via 《ChemMedChem》2019,14(18):1641-1652
A series of 2-phenyloxazoles bearing an amide group at position 4 were designed and synthesized for evaluation as potential inhibitors of human recombinant monoamine oxidases (hrMAOs). Results of kinetics experiments demonstrated that all compounds behave as competitive MAO inhibitors, with good selectivity toward the MAO-B isoform. The most potent and selective derivatives are characterized by inhibition constant (Ki) values in the sub-micromolar range and a good selectivity index (Ki MAO-A/Ki MAO-B>50). Some derivatives were also found to be able to inhibit MAO activity in nerve growth factor (NGF)-differentiated PC12 cells, taken as a model of neuronal cells. In particular, 2-(2-hydroxyphenyl)-N-phenyloxazole-4-carboxamide (compound 4 a ) may be a promising new scaffold, exerting the highest selectivity and inhibitory effect toward MAOs in NGF-differentiated PC12 cell lysates, without compromising cell viability. Molecular docking analysis allowed a rationalization of the experimentally observed binding affinity and selectivity. 相似文献
43.
Daniele Bortoluzzi Claudio CinquemaniElisa Torresani Sara Spilimbergo 《The Journal of Supercritical Fluids》2011,56(1):6-13
The main aim of this work is to investigate the effect of CO2 and N2O under pressure in aqueous solution - both on-line and in real-time. In particular, the paper presents the kinetics of pH behaviour of either slightly buffered minimal medium (MM) or non-buffered solution (Ringer solution) during high-pressure treatment at 5, 30 and 60 bar at 25 °C.An innovative spectrophotometric approach has been developed: an optical fiber conducted the inlet signal of a light source into the high-pressure reactor, while another fiber conducted the outlet signal to a spectrometer, thus, obtaining measurements on-line and real-time.CO2 treatment resulted in a pH decrease down to 3.0 in Ringer solution with the equilibrium being reached after 800 s, while the slightly buffered MM allows only for a decrease down to 4.5 with equilibrium being reached after slightly more than 40 s at 60 bar.N2O treatment, as expected, did not lead to any acidification of the treated medium at any conditions tested.Furthermore, a mathematical model describing both the solubilization kinetics of CO2 and in aqueous solution and the decrease of extracellular pH has been implemented. This model may easily be applied to different reactor configurations. The theoretical results and the goodness of the fit has been verified using the experimental results showing a good accuracy of the complex phenomena with a simplification that is of vital relevance for technical processes. 相似文献
44.
45.
Target Hopping as a Useful Tool for the Identification of Novel EphA2 Protein–Protein Antagonists 下载免费PDF全文
Dr. Daniele Pala Dr. Simonetta Russo Dr. Riccardo Castelli Dr. Iftiin Hassan‐Mohamed Dr. Carmine Giorgio Dr. Alessio Lodola 《ChemMedChem》2014,9(1):67-72
Lithocholic acid (LCA), a physiological ligand for the nuclear receptor FXR and the G‐protein‐coupled receptor TGR5, has been recently described as an antagonist of the EphA2 receptor, a key member of the ephrin signalling system involved in tumour growth. Given the ability of LCA to recognize FXR, TGR5, and EphA2 receptors, we hypothesized that the structural requirements for a small molecule to bind each of these receptors might be similar. We therefore selected a set of commercially available FXR or TGR5 ligands and tested them for their ability to inhibit EphA2 by targeting the EphA2‐ephrin‐A1 interface. Among the selected compounds, the stilbene carboxylic acid GW4064 was identified as an effective antagonist of EphA2, being able to block EphA2 activation in prostate carcinoma cells, in the micromolar range. This finding proposes the “target hopping” approach as a new effective strategy to discover new protein–protein interaction inhibitors. 相似文献
46.
Paola Maroni Paola Bendinelli Daniele Morelli Lorenzo Drago Alessandro Luzzati Giuseppe Perrucchini Chiara Bonini Emanuela Matteucci Maria Alfonsina Desiderio 《International journal of molecular sciences》2015,16(12):28108-28122
In order to become established in the skeleton, metastatic cells disseminating from the breast carcinoma need to acquire organ-specific traits. There are no effective predictors for who will develop bone metastasis to guide long-term predictive therapy. Our purpose was to individuate events critical for bone colonization to make a molecular classification of breast carcinoma useful for bone-metastasis outcome. In dysplasia adjacent to carcinoma and in pair-matched specimens of bone metastasis we examined SPARC expression and localization as well as Endothelin 1/ETAR signals by immunohistochemistry, and the evaluation of plasma levels of SPARC by ELISA was also performed. In patients with breast carcinoma metastasizing to bone, SPARC and Endothelin 1/ETAR axis were highly expressed from dysplasia until bone metastasis, but the SPARC plasma level was as low as that of normal women, in contrast to patients that never develop bone metastasis, suggesting that circulating SPARC was counter adhesive. Altogether, the early identification of SPARC/Endothelin 1/ETAR in dysplastic lesions would be important to devise therapies preventing metastasis engraftment, since often carcinoma cells spread to distant organs at the time or even before patients present with cancer. 相似文献
47.
Silvia Tabasso Silvia Berto Roberta Rosato Janeth Alicia Tafur Marinos Marco Ginepro Vincenzo Zelano Pier Giuseppe Daniele Enzo Montoneri 《International journal of molecular sciences》2015,16(2):3405-3418
This work reports a study of the proton-binding capacity of biopolymers obtained from different materials supplied by a municipal biowaste treatment plant located in Northern Italy. One material was the anaerobic fermentation digestate of the urban wastes organic humid fraction. The others were the compost of home and public gardening residues and the compost of the mix of the above residues, digestate and sewage sludge. These materials were hydrolyzed under alkaline conditions to yield the biopolymers by saponification. The biopolymers were characterized by 13C NMR spectroscopy, elemental analysis and potentiometric titration. The titration data were elaborated to attain chemical models for interpretation of the proton-binding capacity of the biopolymers obtaining the acidic sites concentrations and their protonation constants. The results obtained with the models and by NMR spectroscopy were elaborated together in order to better characterize the nature of the macromolecules. The chemical nature of the biopolymers was found dependent upon the nature of the sourcing materials. 相似文献
48.
Prof. Silvia Rivara Dr. Daniele Pala Dr. Alessio Lodola Prof. Marco Mor Dr. Valeria Lucini Dr. Silvana Dugnani Prof. Francesco Scaglione Dr. Annalida Bedini Dr. Simone Lucarini Prof. Giorgio Tarzia Prof. Gilberto Spadoni 《ChemMedChem》2012,7(11):1954-1964
The design of compounds selective for the MT1 melatonin receptor is still a challenging task owing to the limited knowledge of the structural features conferring selectivity for the MT1 subtype, and only few selective compounds have been reported so far. N‐(Anilinoalkyl)amides are a versatile class of melatonin receptor ligands that include nonselective MT1/MT2 agonists and MT2‐selective antagonists. We synthesized a new series of N‐(anilinoalkyl)amides bearing 3‐arylalkyloxy or 3‐alkyloxy substituents at the aniline ring, looking for new potent and MT1‐selective ligands. To evaluate the effect of substituent size and shape on binding affinity and intrinsic activity, both flexible and conformationally constrained derivatives were prepared. The phenylbutyloxy substituent gave the best result, providing the partial agonist 4 a , which was endowed with high MT1 binding affinity (pKi=8.93) and 78‐fold selectivity for the MT1 receptor. To investigate the molecular basis for agonist recognition, and to explain the role of the 3‐arylalkyloxy substituent, we built a homology model of the MT1 receptor based on the β2 adrenergic receptor crystal structure in its activated state. A binding mode for MT1 agonists is proposed, as well as a hypothesis regarding the receptor structural features responsible for MT1 selectivity of compounds with lipophilic arylalkyloxy substituents. 相似文献
49.
Emanuela Tamburri Valeria Guglielmotti Silvia Orlanducci Maria Letizia Terranova Daniela Sordi Daniele Passeri Roberto Matassa Marco Rossi 《Polymer》2012,53(19):4045-4053
The detonation nanodiamond is a novel versatile nanomaterial with tunable properties and surface chemistry. In this work, we report on a template-free method to synthesize polyaniline based nanocomposite fibers during a chemical oxidative precipitation polymerization where the cooperative interactions between nanodiamond and polyaniline nucleates trigger the final morphology of the nanocomposite. FE–SEM and TEM observations evidence the prominent growth of fibril-like structures assembled in 2-D networks of tightly woven, partially oriented fibers. Optical and Raman spectroscopy and X-ray diffraction analyses reveal that the polymer chains are in a protonated emeraldine form and organize themselves in a highly ordered 3-D spatial arrangement. Conductivity measurements performed on isolated fibers by a conductive tip of an AFM apparatus highlight that the diamond filler does not affect the conductive properties of the polyaniline matrix while increases the thermal stability of the polymer as confirmed by TGA studies. 相似文献
50.
Sergio Scognamillo Emilia Gioffredi Massimo Piccinini Massimo Lazzari Valeria Alzari Daniele Nuvoli Roberta Sanna Daniele Piga Giulio Malucelli Alberto Mariani 《Polymer》2012,53(19):4019-4024
Thermoplastic polyurethane (TPU) nanocomposites containing graphene and graphene nanoribbons were obtained by polymerizing 1,4-butanediol with two diisocyanates (namely, 1,6-hexane diisocyanate or isophorone diisocyanate), in which the nanofillers were previously dispersed. Raman spectroscopy and Transmission Electron Microscopy demonstrated the formation of few-layer graphene and graphene nanoribbons dispersed in the monomers. At variance to the methods commonly reported in literature, that used in this work consists of the direct exfoliation of graphite without any chemical manipulation. Apart from the obvious cost and ease advantages, the so-obtained graphene does not contain any carboxy or alkoxy groups formed during the exfoliation process, which, at variance, are typically present in the most commonly reported methods. This finding paves the way toward the large-scale production of graphene and its nanoribbons, which are considered even more interesting than graphene itself for many potential applications. The obtained nanocomposites show a peculiar thermal and rheological behavior due to the presence of the nanofillers and to their reinforcing or plasticizing effect exerted on the TPU matrices. 相似文献