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Neural Computing and Applications - Nowadays, one of the problems in current authentication, authorization and accounting (AAA) model is lack of accurate roadmap of access management in integrated... 相似文献
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Energy consumption for developing countries is sharply increasing due to the higher economic growth due to industrialisation along with population growth and urbanisation. The increasing demand of energy leads to global energy crisis. Selecting the best energy technology and conservation requires both quantitative and qualitative evaluation criteria. The fuzzy set-based approach is one of the well-known theories to handle fuzziness, uncertainty in decision-making and vagueness of information. This paper proposes a new method of intuitionistic fuzzy analytic hierarchy process (IF-AHP) to deal with the uncertainty in decision-making. The new IF-AHP is applied to establish a preference in the sustainable energy planning decision-making problem. Three decision-makers attached with Malaysian government agencies were interviewed to provide linguistic judgement prior to analysing with the new IF-AHP. Nuclear energy has been decided as the best alternative in energy planning which provides the highest weight among all the seven alternatives. 相似文献
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Hameed Al‐Attar Aula A Alwattar Athir Haddad Bassil A Abdullah Peter Quayle Stephen G Yeates 《Polymer International》2021,70(1):51-58
In this work we demonstrate, for the first time, the use of polylactic acid (PLA) as a biodegradable host matrix for the construction of the active emissive layer of organic light‐emitting diode (OLED) devices for potential use in bioelectronics. In this preliminary study, we report a robust synthesis of two fluorescent PLA derivatives, pyrene‐PLA ( AH10 ) and perylene‐PLA ( AH11 ). These materials were prepared by the ring opening polymerisation of l ‐lactide with hydroxyalkyl‐pyrene and hydroxyalkyl‐perylene derivatives using 1,8‐diazabicyclo[5.4.0]undec‐7‐ene as catalyst. OLEDs were fabricated from these materials using a simple device architecture involving a solution‐processed single‐emitting layer in the configuration ITO/PEDOT:PSS/PVK:OXD‐7 (35%): AH10 or AH11 (20%)/TPBi/LiF/Al (ITO, indium tin oxide; PEDOT:PSS, poly(3,4‐ethylenedioxythiophene) doped with poly(styrenesulfonic acid); PVK, poly(vinylcarbazole); OXD‐7, (1,3‐phenylene)‐bis‐[5‐(4‐tert‐butylphenyl)‐1,3,4‐oxadiazole]; TPBi, 2,2′,2″‐(1,3,5‐benzenetriyl)tris(1‐phenyl‐1H‐benzimidazole)). The turn‐on voltage for the perylene OLED at 10 cd m–2 was around 6 V with a maximum brightness of 1200 cd m–2 at 13 V. The corresponding external quantum efficiency and device current efficiency were 1.5% and 2.8 cd A–1 respectively. In summary, this study provides proof of principle that OLEDs can be constructed from PLA, a readily available and renewable bio‐source. © 2020 The Authors. Polymer International published by John Wiley & Sons Ltd on behalf of Society of Industrial Chemistry. 相似文献
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Amir Mowla Mehrez Agnaou Tanyakarn Treeratanaphitak Hector M. Budman Nasser M. Abukhdeir Marios A. Ioannidis 《American Institute of Chemical Engineers》2020,66(6):e16959
We quantify the ability of the two-fluid Euler–Euler model to predict the overall gas hold-up during two-phase flow in vertical columns using a combination of experiments and simulations. Gas hold-up in a bubble column and gas hold-up in the less-frequently studied co-current flow are investigated. For homogeneous flow characterized by nearly uniform bubble size, Euler–Euler model predictions are within 10% of the experimental values for both modes of operation, if the bubble diameter supplied as input to the model is the average bubble diameter in the physical system. This also holds true for heterogeneous flow in bubble columns despite the presence of a broad distribution of bubble sizes, if turbulence and bubble swarm effects on momentum exchange between phases are properly accounted for. Swarm corrections adequate for bubble columns, are less successful for co-current heterogeneous flow, for which gas hold-up predictions are least accurate (average error of 22%). 相似文献
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M. J. Ghoushji Reza Alebrahim R. Zulkifli A. B. Sulong S. Abdullah C. H. Azhari 《Iranian Polymer Journal》2018,27(8):563-575
Using metallic materials in automotive structures increases weight, fuel consumption and cost, therefore, certain trends have begun to use lightweight and cheaper materials. Fibre composites are used in automotive applications because they are stiff, lightweight and stronger than bulk material, as well as they have a comparable energy-absorbing capacity to that of metallic materials. The aim of this study is to investigate the potentials in natural ramie/bio-epoxy composite in crash energy absorption applications. Cubic specimens consisted of 12, 24 and 30 plies of ramie/bio-epoxy laminates with 50, 80 and 120 mm long which were prepared by hand layup method. Static axial compression load was then applied and the energy-absorbing capability of the ramie/epoxy composite was evaluated. The crashworthiness characteristics of the composite tubes were evaluated by measuring the average and peak crushing load, specific energy absorption, total absorbed energy and crush force efficiency in quasi-static axial compression. The failure mode and behaviour of the tubes were investigated by taking photographs and recording the load–displacement curves during the test accomplishment. The test results indicated that natural ramie/bio-epoxy composite tube has the great potential to be used as an effective energy-absorbing device. 相似文献
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Nasser A.M. Barakat A.H. Zaki Enas Ahmed A.A. Farghali Fahad S. Al-Mubaddel 《International Journal of Hydrogen Energy》2018,43(16):7990-7997
Theoretically, tri-ammonium phosphate (NH4)3PO4 embeds considerable amount of hydrogen. Typically, the expected hydrogen release from this cheap and stable material is 73.83 mmol/gsalt if a proper catalyst is exploited in the hydrolysis reaction. In this study FexCo1?x-doped titanium oxide nanotubes are introduced as an efficient photocatalyst under solar radiation. The introduced modified titanium oxide nanotubes have been prepared in two successive steps. First, Na-doped TiO2 nanotubes were synthesized by hydrothermal treatment in presence of 10 N NaOH solution at 160 °C for 16 h. Then, doping by the proposed metals was carried out by ion exchange process in a microwave oven. X-ray photoelectron microscopy (XPS) and transmission electron microscopy (TEM) confirmed the success of the doping process and the nanotubular morphology, respectively. Study the photo characteristics indicated that the proposed metal doping shifted the band gap from UV to the visible light region as the estimated band gap energies for the as-prepared and doped nanotubes were 3.4 and 2.1 eV, respectively. Moreover, distinct enhancement for the visible light absorption capacity was observed. Accordingly, a distinguished improvement in the photocatalytic activity toward tri-ammonium phosphate hydrolysis was observed. However, the two metals content has a strong influence on the amount of the obtained hydrogen per gram of tri-ammonium phosphate salt. Numerically, the maximum obtained hydrogen was 4.0, 11.2, 11.2, 11.6, 13.4, 16.5, 17.4, 13.4 and 9.8 mmol/gsalt for the pristine TiO2, and FexCo1?x-doped TiO2 with x = 1, 0.8, 0.6, 0.5, 0.4, 0.3, 0.2, and 0.0, respectively. 相似文献
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