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61.
Raising awareness of the environmental impact of energy generation and consumption has been a recent concern of contemporary society worldwide. Underlying the awareness of energy consumption is an intricate network of perception and social interaction that can be mediated by technology. In this paper we argue that issues regarding energy, environment and technology are very much situated and involve tensions of sociocultural nature. This exploratory investigation addresses the subject by introducing the design of a Socially-inspired Energy Eco-Feedback Technology (SEET), which is composed of an interactive system to trigger and mediate collective savings and a tangible device as a public feedback. Results of an evaluation situated in the context of a school in a socially disadvantaged area in Brazil are discussed, shedding light on the sociocultural aspects related to the subject. The role of the SEET to motivate energy awareness collectively among the social group is assessed, as well as the design characteristics that contributed to that. Outcomes bring to light social aspects and dynamics that would hardly have been predicted, evidencing critical factors related to a socially inspired design approach in the energy awareness domain. 相似文献
62.
The purpose of this paper is to show how the results of an optimisation model that can be integrated with the decisions made within a simulation model to schedule back-end operations in a semiconductor assembly and test facility. The problem is defined by a set of resources that includes machines and tooling, process plans for each product and the following four hierarchical objectives: minimise the weighted sum of key device shortages, maximise weighted throughput, minimise the number of machines used and minimise the makespan for a given set of lots in queue. A mixed integer programming model is purposed and first solved with a greedy randomised adaptive search procedure (GRASP). The results associated with the prescribed facility configuration are then fed to the simulation model written in AutoSched AP. However, due to the inadequacy of the options built into AutoSched, three new rules were created: the first two are designed to capture the machine set-up profiles provided by the GRASP and the third to prioritise the processing of hot lots containing key devices. The computational analysis showed that incorporating the set-up from the GRASP in dynamic operations of the simulation greatly improved its performance with respect to the four objectives. 相似文献
63.
K. S. Rodolfo A. T. Arguden R. U. Solidum J. V. Umbal 《Bulletin of Engineering Geology and the Environment》1989,40(1):55-66
Mayon Volcano in the Philippines, one the world's most active, is situated in a moist, tropical-maritime climate with frequent typhoons. A third of Mayon's eruptions generate destructive lahars (volcanic debris flows and hyperconcentrated streamflows). Lahars also occur during quiescent periods when monsoons and typhoons deliver rains of appropriate intensity and duration to the loose debris on the volcano slopes. Both eruption- and post-eruptive lahars occur most frequently during the typhoon-prone October–December season of the Northeast Monsoon. Post-eruptive lahars, the most poorly documented, are exemplified by a debris-flow event triggered by Saling, a typhoon of only moderate intensity, that occurred in Mabinit Channel on the southeast Mayon flank on October 17–18, 1985, one year after the last Mayon eruption. Detailed pre- and post-Saling surveys docment channel deepening of up to 4 m and maximum lateral erosion of 66 m. The debris flows left prominent, discontinuous multi-level terraces along the length of Mabinit Channel, either from pulsations due to temporary channel blockage, or as levee deposits. A significant volume of debris overtopped channel bends at 250–200 m elevations, coalescing to cover a 200,000 m2 area of 4.5° slope with bouldery lateral deposits 1 m thick on the average. Channelized flows below this level plugged 0.5 km of the original channel and replaced it with a new conduit of comparable size. The Saling debris-flow deposits have a remarkably uniform sand-silt mode and less prominent, more variable modes in the pebble-boulder range. Shear strengths of the lateral flows ranged from 0.46×104 to 2.32×104 dn cm?2; those of the channelized flows at the plug were significantly higher. Reconstructed flow velocity was 3.8 m sec?1. 相似文献
64.
The aim of this paper is to obtain an explicit expression, instead of using a recursive method, for the nth term coefficient of the generalized Baker–Campbell–Hausdorff–Dynkin (gBCHD) formula. The gBCHD formula has been applied to control theory, specially to nonholonomic motion planning. 相似文献
65.
Mariela C. Olguín Viviana O. Salvadori Rodolfo H. Mascheroni Domingo A. Tarzia 《International Journal of Heat and Mass Transfer》2008,51(17-18):4379-4391
The coupled problem of heat and mass transfer during the solidification of high-water content materials like soils, foods, tissues and phase-change materials is developed. Assuming quasi-steady heat conduction in the frozen region, the system leads to a set of coupled ordinary differential equations. The model takes into account the influence of material characteristics and process variables on the advance of the freezing and sublimation fronts, temperature and water vapour profiles and weight loss. It was validated against the analytical solution of the freezing (without surface ice sublimation) of a semi-infinite medium and was extensively used to perform a parametric study. 相似文献
66.
Graphene: Large‐Area Si‐Doped Graphene: Controllable Synthesis and Enhanced Molecular Sensing (Adv. Mater. 45/2014) 下载免费PDF全文
67.
68.
Amel Djoudi Rodolfo Molina-Pea Natalia Ferreira Ilaria Ottonelli Giovanni Tosi Emmanuel Garcion Frank Boury 《International journal of molecular sciences》2022,23(20)
Hyaluronic acid (HA) is a Glycosaminoglycan made of disaccharide units containing N-acetyl-D-glucosamine and glucuronic acid. Its molecular mass can reach 10 MDa and its physiological properties depend on its polymeric property, polyelectrolyte feature and viscous nature. HA is a ubiquitous compound found in almost all biological tissues and fluids. So far, HA grades are produced by biotechnology processes, while in the human organism it is a major component of the extracellular matrix (ECM) in brain tissue, synovial fluid, vitreous humor, cartilage and skin. Indeed, HA is capable of forming hydrogels, polymer crosslinked networks that are very hygroscopic. Based on these considerations, we propose an overview of HA-based scaffolds developed for brain cancer treatment, central and peripheral nervous systems, discuss their relevance and identify the most successful developed systems. 相似文献
69.
The linear-extended neutron diffusion equation (LENDE) is the volume-averaged neutron diffusion equation (VANDE) which includes two correction terms: the first correction is related with the absorption process of the neutron and the second is a contribution to the neutron diffusion, both parameters are related to neutron effects on the interface of a heterogeneous configuration. In this work an analysis of a plane source in a semi-infinite homogeneous medium was considered to study the effects of the correction terms and the results obtained with the linear-extended neutron diffusion equation were compared against a semi-analytical benchmark for the same case. The comparison of the results demonstrate the excellent approach between the linear-extended diffusion theory and the selected benchmark, which means that the correction terms of the VANDE are physically acceptable. 相似文献
70.
Elemental and mineral characterisation of Coastal Antarctic Aerosols in snow using PIXE and SEM-EDAX
Grazia Ghermandi Paolo Laj Margherita Capotosto Rodolfo Cecchi Carlo Riontino 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1999,150(1-4):392-397
The chemical constituents of snow from a 3 m pit sampled at a coastal Antarctic site were characterised by means of PIXE and SEM-EDAX. Oxygen isotope dating revealed that the pit spanned an 8-year period, from 1986 to 1994. Concentrations measured by PIXE ranged from less than 1 ng g−1 of H2O for Cu, and Zn to several tens of ng g−1 for Si, S and Cl. The major elements found were Si, S, Al, and Na, which contributed more than 75% of the element loading. Snow layers with elevated Cl concentration were regularly found along the pit. The mineralogy of the insoluble particles determined by SEM-EDAX analyses showed that quartz, plagioclase and clays were the prevalent minerals. The proportion of each element in the insoluble phase was comparable with that previously found in similar studies. 相似文献