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101.
Vallortigara Giorgio; Cailotto Maurizio; Zanforlin Mario 《Canadian Metallurgical Quarterly》1990,104(4):361
Male and female chicks (Gallus gallus) were trained at 4 days old to run along a corridor to reach a goal box that contained either cagemates (social reinforcement) or food (nonsocial reinforcement). Females ran faster when social reinforcement was used, whereas males ran faster with nonsocial reinforcement. When social reinforcement was used with a V-shaped runway, in which chicks had to proceed toward the goal object in an indirect fashion, sex differences were reversed. The results may be due to stronger social reinstatement tendencies in females than in males: Higher levels of social motivation facilitate behavioral performance when the task is easy (straight runway) and inhibit it when the task is difficult (V-shaped runway). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
Maurizio Aceto Ornella Abollino Maria Concetta Bruzzoniti Edoardo Mentasti Corrado Sarzanini Mery Malandrino 《Food Additives & Contaminants》2002,19(2):126-133
Metals in wine occur at the mg l 1 level or less and, though not directly related to the taste of the final product, their content should be determined because excess is undesirable, and in some cases prohibited, due to potential toxicity. Lead content in wine, for example, is restricted in several states by legislation to guarantee consumer health protection. Of several methods for metal determination, techniques of atomic spectroscopy are the most sensitive and rapid. Most of the elements present in wine can be determined with these techniques, at concentrations ranging from the mg l -1 to the μg l -1 level. Here, inductively coupled plasma-atomic emission spectrometry (ICP-AES), flame atomic absorption spectrometry (flame-AAS) and graphite furnace-atomic absorption spectrometry (GF-AAS) are compared for their characteristics as employed in metal determination in wine. 相似文献
103.
Aerodynamic and thermal investigations for the new Lyon/Turin Cross-Alpine rail link 总被引:1,自引:0,他引:1
Maurizio Cavagnaro Jean Brulard 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》1997,12(3):377-384
The paper describes a system for assessing unambiguously the quality of tunnel blasting. The system can be used to compare the working practices of different operations. The economic implications of blasting accuracy are analysed on the basis of data collected in actual operations. Drilling accuracy is identified as a primary factor in reducing tunnelling costs. 相似文献
104.
105.
The Fight against the Influenza A Virus H1N1: Synthesis,Molecular Modeling,and Biological Evaluation of Benzofurazan Derivatives as Viral RNA Polymerase Inhibitors 下载免费PDF全文
Dr. Mafalda Pagano Dr. Daniele Castagnolo Dr. Martina Bernardini Anna Lucia Fallacara Ilaria Laurenzana Davide Deodato Dr. Ulrich Kessler Dr. Beatrice Pilger Dr. Lilli Stergiou Dr. Stephan Strunze Dr. Cristina Tintori Prof. Maurizio Botta 《ChemMedChem》2014,9(1):129-150
The influenza RNA polymerase complex, which consists of the three subunits PA, PB1, and PB2, is a promising target for the development of new antiviral drugs. A large library of benzofurazan compounds was synthesized and assayed against influenza virus A/WSN/33 (H1N1). Most of the new derivatives were found to act by inhibiting the viral RNA polymerase complex through disruption of the complex formed between subunits PA and PB1. Docking studies were also performed to elucidate the binding mode of benzofurazans within the PB1 binding site in PA and to identify amino acids involved in their mechanism of action. The predicted binding pose is fully consistent with the biological data and lays the foundation for the rational development of more effective PA–PB1 inhibitors. 相似文献
106.
Elena Mele Maurizio Toreno Giuseppe Brandonisio Antonello De Luca 《The Structural Design of Tall and Special Buildings》2014,23(2):124-145
The originality of form is one of the new trends that can be identified in the current design of tall buildings. In this design trend, the so‐called diagrid structures, which represent the latest mutation of tubular structures, play a major role due to their inherent esthetic quality, structural efficiency and geometrical versatility. In this paper, an overview on application of such typology to high‐rise buildings is carried out; in particular, in the first part of the paper, the peculiarities of diagrid systems are described: starting from the analysis of the internal forces arising in the single diagrid module due to vertical and horizontal loads, the resisting mechanism of diagrid buildings under gravity and wind loads is described, and recent researches and studies dealing with the effect of geometry on the structural behavior are discussed. In the second part of the paper, a comparative analysis of the structural performance of some recent diagrid tall buildings, characterized by different number of stories and different geometries, namely the Swiss Re building in London, the Hearst Headquarters in New York and the West Tower in Guangzhou, is carried out, and some general design remarks are derived. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
107.
Elizaveta Kon Giuseppe Filardo Francesco Perdisa Alessandro Di Martino Maurizio Busacca Federica Balboni Andrea Sessa Maurilio Marcacci 《Journal of materials science. Materials in medicine》2014,25(10):2437-2444
The increasing interest in the role of subchondral bone with regard to articular surface disease led to the development of new bioengineered strategies. Aim of this study is to evaluate the clinical and MRI outcome after the implantation of a nanostructured biomimetic three-phasic collagen–hydroxyapatite construct for the treatment of chondral and osteochondral defects of the knee in a large cohort of patients. Seventy-nine patients (63 M, 16 W), affected by grade III–IV femoral condyle or trochlea chondral lesions or osteochondritis dissecans (OCD) were consecutively treated. Mean age was 31.0 ± 11.3 years, mean lesion size was 3.2 ± 2.0 cm2. Fifty patients underwent previous surgeries, concurrent procedures were necessary in 39 cases. The clinical outcome was evaluated using the IKDC and Tegner scores at 12 and 24 months of follow-up. At follow-up times an MRI was performed and evaluated with the MOCART score. All the scores improved significantly from the baseline. IKDC subjective score showed a further increase between 12 and 24 months of follow-up, and 82.2 % of the patients improved their symptoms at the final evaluation. Patients affected by OCDs had better results than those with degenerative lesions. Some abnormal MRI findings were present, even though no correlation was found with the clinical outcome. This one-step biomimetic approach developed to favor osteochondral tissue regeneration is effective in treating knees affected by damages of the articular surface, leading to a significant clinical improvement. However, abnormal MRI findings were present, even if not correlated with the clinical outcome. 相似文献
108.
109.
Gian Piero Celata Francesco Dannibale Andrea Chiaradia Maurizio Cumo 《International Journal of Heat and Mass Transfer》1998,41(24):396
The present work deals with the results of an experimental investigation on heat transfer in water cooled vertical pipes, for thermal–hydraulic conditions ranging from forced convective flow to mixed convective flow. The flow of water in the pipe is upwards.Experimental data confirm the reduction in the heat transfer rate for mixed convection in upward heat flow, mainly due to the laminarization effect in the near-wall region (buoyancy effect) . They are in a very good agreement with numerical methods, such as the k–-model.A new method for the calculation of the heat transfer coefficient in upward mixed convection heated flow is proposed. It is based on the well-known superposition method (heated downflow) modified accounting for the phenomenology of the upward heated flow in comparison with downflow heated conditions. 相似文献
110.
Maurizio Penco Arifur RhamanGloria Spagnoli Gerardus JanszenLuca Di Landro 《Materials Letters》2011,65(14):2107-2110
Self-healing behavior of ionomer blends containing both rapidly crystallizing phase and with higher amount of amorphous phase has not yet been studied. This work gives a new insight to understand the development of materials with intrinsic self-healing property. In particular, binary blends based on poly(ethylene-co-methacrylic acid sodium salt) (EMNa)/Poly(vinyl alcohol-co-ethylene) (EVA) and epoxidized natural rubber (ENR), were studied by ballistic puncture tests. In the composition range explored (15-50 wt.% of EVA and ENR), the self-healing characteristics decrease with the increasing amount of EVA but are maintained in all ranges for ENR/EMNa blends. The ballistic damage initiated autonomous healing was observed by optical microscopy and the healing was further analyzed by thermal and mechanical behaviors of the blend materials. 相似文献