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991.
Rusciano G De Luca AC Pesce G Sasso A Oliviero G Amato J Borbone N D'Errico S Piccialli V Piccialli G Mayol L 《Analytical chemistry》2011,83(17):6849-6855
In this work, we establish the use of surface-enhanced Raman scattering (SERS) as a label-free analytical technique for the direct detection of G-quadruplex formation. In particular, we demonstrate that SERS analysis allows the evaluation of the relative stability of G quadruplexes that differ for the number of G tetrads and investigate several structural features of quadruplexes, such as the orientation of glycosidic bonds, the identification of distortions in the sugar-phosphate backbone, and the degree of hydrogen-bond solvation. Herein, the fluctuation of the SERS spectra, due to the specific interaction of vibrational modes with the SERS-active substrate, is quantitatively analyzed before and after quadruplex formation. The results of this study suggest a perpendicular orientation of the quadruplexes (with or without the 3'-tetra end linker) with respect to the silver colloidal surface, which opens new perspectives for the use of SERS as a label-free analytical tool for the study of the binding mode between quadruplexes and their ligands. 相似文献
992.
Stefano Pagliara Iacopo Carnacina Thendiyath Roshni 《Canadian Metallurgical Quarterly》2011,137(7):629-638
Rock chutes or block ramps are fishway passages with low environmental impact. They also contribute to reaeration of rivers with low dissolved oxygen content, owing to the turbulence enhanced by their three-dimensional macroroughness conditions. This paper analyzes the air entrainment inception in flows over beds in macroroughness condition and the self-aerated flow features of the developing flow downstream of the inception point. Air concentration, inception point locations, and water depth elevations have been measured on two different scaled chutes for slopes ranging between 1V:5.88H and 1V:2.17H. Moreover, two different ogee crest lengths have been tested to assess the role of the inlet conditions on the location of the inception point. New equations have been developed to estimate the location of the point of inception and the respective water depth. Longitudinal variations of the mean air concentration downstream from the inception point have been studied and compared with data from the literature. An expression is presented to estimate the optimum length of the block ramp in natural rivers for maximizing air-water mixing. 相似文献
993.
Eliseo Visca Emanuele Cacciotti Anton Komarov Stefano Libera Nikolay Litunovsky Alexey Makhankov Andrea Mancini Mario Merola Aldo Pizzuto Bruno Riccardi Selanna Roccella 《Fusion Engineering and Design》2011,86(9-11):1591-1594
ENEA is involved in the International Thermonuclear Experimental Reactor (ITER) R&D activities. During the last years ENEA has set up and widely tested a manufacturing process, named Hot Radial Pressing (HRP), suitable for the construction of high heat flux plasma-facing components, such as the divertor targets.In the frame of the EFDA contract six mock-ups were manufactured by HRP in the ENEA labs using W monoblocks supplied by the Efremov Institute in St. Petersburg, Russian Federation and IG CuCrZr tubes.According to the technical specifications the mock-ups were examined by ultrasonic technique and after their acceptance they were delivered to the Efremov Institute TSEFEY-M e-beam facility for the thermal fatigue testing. The test consisted in 3000 cycles of 15 s heating and 15 s cooling at 10 MW/m2 and finally 1000 cycles at 20 MW/m2.After the testing the ultrasonic non-destructive examination was repeated and the results compared with the investigation performed before the testing.A microstructure modification of the W monoblock material due to the overheating of the surfaces and the copper interlayer structure modification were observed in the high heat flux area.The leakage points of the mock-ups that did not conclude the testing were localized in the middle of the monoblock while they were expected between two monoblocks.This paper reports the manufacturing route, the thermal fatigue testing, the pre and post non destructive examination and finally the results of the destructive examination performed on the monoblock small scale mock-ups. 相似文献
994.
Ingo Kuehn Miikka Kotamaki Laurent Schmieder Jean-Jacques Cordier Stefano Chiocchio Leontin Carafa James Klingsmith Laurent Patisson Giuliano Rigoni Thibault Tsedri 《Fusion Engineering and Design》2011,86(6-8):632-635
The ITER site consists of almost 30 buildings to service the Tokamak machine which is located in the centre of the Tokamak Complex facility with the Tokamak-, Diagnostic- and Tritium building.The design of a large part of the ITER plant systems will be executed by the ITER Domestic Agencies or their industrial suppliers under functional specifications provided by the ITER Organization. At the same time, the detailed design of the building is carried out by the European Domestic Agency ‘Fusion for Energy’ (F4E).In order to allow an efficient identification of the ITER configuration as well as to manage the concurrent engineering activities and to simplify the identification and assessment of changes, the design of each ITER plant systems is described in the so-called Configuration Management Models (CMM). These are light CATIA® 3D models that define the required space envelope and the physical interfaces in-between the systems and the buildings.The paper describes the procedure adopted for the control of the baseline configuration of the Tokamak Complex facility and Auxiliary Buildings with their associated plant systems and illustrates the current status as well as recent developments in the different systems. 相似文献
995.
Stefano Paolo Corgnati Enrico Fabrizio Daniela Raimondo Marco Filippi 《Building Simulation》2011,4(2):97-105
Maintaining suitable indoor climate conditions is a need for the occupants’ well being, while requiring very strictly thermal
comfort conditions and very high levels of indoor air quality in buildings represents also a high expense of energy, with
its consequence in terms of environmental impact and cost. In fact, it is well known that the indoor environmental quality
(IEQ), considering both thermal and indoor air quality aspects, has a primary impact not only on the perceived human comfort,
but also on the building energy consumption. This issue is clearly expressed by the European Energy Performance of Buildings
Directive 2002/92/EC, together with the most recent 2010/31/EU, which underlines that the expression of a judgment about the
energy consumption of a building should be always joint with the corresponding indoor environmental quality level required
by occupants. To this aim, the concept of indoor environment categories has been introduced in the EN 15251 standard. These
categories range from I to III, where category I refers to the highest level of indoor climate requirement. In the challenge
of reducing the environmental impact for air conditioning in buildings, it is essential that IEQ requirements are relaxed
in order to widen the variations of the temperature ranges and ventilation air flow rates. In this paper, by means of building
energy simulation, the heating and cooling energy demand are calculated for a mechanically controlled office building where
different indoor environmental quality levels are required, ranging from category I to category III of EN 15251. The building
is located in different European cities (Moscow, Torino and Athens), characterized by significantly different wheatear conditions.
The mutual relation between heating and cooling energy demand and the required levels of IEQ is highlighted. The simulations
are performed on a typical office room which is adopted as a reference in validation tests of the European Standard EN 15265
to validate calculation procedures of energy use for space heating and cooling. 相似文献
996.
997.
998.
This paper discusses some of the methods that can be employed for calculating shielding of proton accelerators, showing that a simple analytical model is often useful for a first estimate before going into complex Monte Carlo simulations. In particular what we call the Monte Carlo 'hybrid' approach, which employs source terms and attenuation length data calculated by Monte Carlo simulations under generic geometrical conditions, with a point-source line-of-sight model is discussed. Examples are given of the application of this method to the shielding calculations of two versions of the CERN SPL (2- and 3.5-GeV energy), comparing its results with Monte Carlo simulations of the full geometry. 相似文献
999.
Bonanni V Bonetti S Pakizeh T Pirzadeh Z Chen J Nogués J Vavassori P Hillenbrand R Åkerman J Dmitriev A 《Nano letters》2011,11(12):5333-5338
We introduce a new perspective on magnetoplasmonics in nickel nanoferromagnets by exploiting the phase tunability of the optical polarizability due to localized surface plasmons and simultaneous magneto-optical activity. We demonstrate how the concerted action of nanoplasmonics and magnetization can manipulate the sign of rotation of the reflected light's polarization (i.e., to produce Kerr rotation reversal) in ferromagnetic nanomaterials and, further, how this effect can be dynamically controlled and employed to devise conceptually new schemes for biochemosensing. 相似文献
1000.
Quadrupole plasmon and (octupolar) Fano resonances are induced in lithographically fabricated theta-shaped ring-rod gold nanostructures. The optical response is characterized by measuring the light scattered by individual nanostructures. When the nanorod is brought within 3 nm of the ring wall, a weak quadrupolar resonance is observed due to capacitive coupling, and when a necklike conductive bridge links the nanorod to the nanoring the optical response changes dramatically bringing the quadrupolar resonance into prominence and creating an octupolar Fano resonance. The Fano resonance is observed due to the destructive interference of the octupolar resonance with the overlapping and broadened dipolar resonance. The quadrupolar and Fano resonances are further enhanced by capacitive coupling (near-field interaction) that is favored by the theta-shaped arrangement. The interpretation of the data is supported by FDTD simulation. 相似文献