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141.
P. Lopez A. Vercet A. C. Sanchez J. Burgos 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1998,207(3):249-252
The resistance of tomato pectic enzymes to manothermosonication (MTS), a combined treatment of heat and ultrasound under
moderate pressure, was studied. Pectinmethylesterase (PMF) and polygalacturonases (PG) I and II were inactivated much more
efficiently by MTS than by simple heating. In MTS inactivation of these enzymes, the effect of heat and ultrasonic waves was
synergistic. D values [the time required for the (original) enzyme activity to decrease by 90%] for PME heat inactivation
at 62.5 °C were reduced 52.9-fold by MTS and those for PG I at 86 °C and PG II at 52.5 °C, 85.8-fold and 26.3-fold, respectively.
Received: 23 January 1998 / Revised version: 23 March 1998 相似文献
142.
Susan Tarka Sanchez Jeremy Woods Mark Akhurst Matthew Brander Michael O'Hare Terence P. Dawson Robert Edwards Adam J. Liska Rick Malpas 《Journal of the Royal Society Interface》2012,9(71):1105-1119
The expansion of land used for crop production causes variable direct and indirect greenhouse gas emissions, and other economic, social and environmental effects. We analyse the use of life cycle analysis (LCA) for estimating the carbon intensity of biofuel production from indirect land-use change (ILUC). Two approaches are critiqued: direct, attributional life cycle analysis and consequential life cycle analysis (CLCA). A proposed hybrid ‘combined model’ of the two approaches for ILUC analysis relies on first defining the system boundary of the resulting full LCA. Choices are then made as to the modelling methodology (economic equilibrium or cause–effect), data inputs, land area analysis, carbon stock accounting and uncertainty analysis to be included. We conclude that CLCA is applicable for estimating the historic emissions from ILUC, although improvements to the hybrid approach proposed, coupled with regular updating, are required, and uncertainly values must be adequately represented; however, the scope and the depth of the expansion of the system boundaries required for CLCA remain controversial. In addition, robust prediction, monitoring and accounting frameworks for the dynamic and highly uncertain nature of future crop yields and the effectiveness of policies to reduce deforestation and encourage afforestation remain elusive. Finally, establishing compatible and comparable accounting frameworks for ILUC between the USA, the European Union, South East Asia, Africa, Brazil and other major biofuel trading blocs is urgently needed if substantial distortions between these markets, which would reduce its application in policy outcomes, are to be avoided. 相似文献
143.
Abstract We determine the far-field divergence angle θ 00 (θ 01) resulting from the diffraction of a TEM00 (TEM01) beam incident on a circular aperture. It is demonstrated that, with a suitable choice of the aperture radius, the ratio θ 01/θ 00 is enhanced to about 2, while its value is 1.64 without the aperturing effect. It is shown that this effect allows high discrimination between TEM00 and TEM01 modes either in the case of a spatial filter or in the case of an apertured resonator. 相似文献
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145.
M. Vinet P. BatudeC. Tabone B. PrevitaliC. LeRoyer A. PouydebasqueL. Clavelier A. ValentianO. Thomas S. MichaudL. Sanchez L. BaudA. Roman V. CarronF. Nemouchi V. MazzocchiH. Grampeix A. AmaraS. Deleonibus O. Faynot 《Microelectronic Engineering》2011,88(4):331-335
After a short reminder of the principle of monolithic 3D integration, this paper firstly reviews the main technological challenges associated to this integration and proposes solutions to assess them. Wafer bonding is used to have perfect crystalline quality of the top layer at the wafer scale. Thermally stabilized silicide is developed to use standard salicidation scheme in the bottom layer. Finally a fully depleted SOI low temperature process is demonstrated for top layer processing (overall temperature kept below 650 °C). In a second part the electrical results obtained within this integration scheme are summarized: mixed Ge over Si invertor is demonstrated and electrostatic coupling between top and bottom layer is used to shift the threshold voltage of the top layer. Finally circuit opportunities such as stabilized SRAM or gain in density are investigated. 相似文献
146.
TiO<Subscript>2</Subscript> nanocrystals grown on graphene as advanced photocatalytic hybrid materials 总被引:2,自引:0,他引:2
Yongye Liang Hailiang Wang Hernan Sanchez Casalongue Zhuo Chen Hongjie Dai 《Nano Research》2010,3(10):701-705
A graphene/TiO2 nanocrystals hybrid has been successfully prepared by directly growing TiO2 nanocrystals on graphene oxide (GO) sheets. The direct growth of the nanocrystals on GO sheets was achieved by a two-step
method, in which TiO2 was first coated on GO sheets by hydrolysis and crystallized into anatase nanocrystals by hydrothermal treatment in the second
step. Slow hydrolysis induced by the use of EtOH/H2O mixed solvent and addition of H2SO4 facilitates the selective growth of TiO2 on GO and suppresses growth of free TiO2 in solution. The method offers easy access to the GO/TiO2 nanocrystals hybrid with a uniform coating and strong interactions between TiO2 and the underlying GO sheets. The strong coupling gives advanced hybrid materials with various applications including photocatalysis.
The prepared graphene/TiO2 nanocrystals hybrid has superior photocatalytic activity to other TiO2 materials in the degradation of rhodamine B, showing an impressive three-fold photocatalytic enhancement over P25. It is
expected that the hybrid material could also be promising for various other applications including lithium ion batteries,
where strong electrical coupling to TiO2 nanoparticles is essential. 相似文献
147.
RA Wain GL Berdejo WN Delvalle RT Lyon LA Sanchez WD Suggs T Ohki E Lipsitz FJ Veith 《Canadian Metallurgical Quarterly》1999,29(1):100-7; discussion 107-9
PURPOSE: Arteriography is the diagnostic test of choice before lower extremity revascularization, because it is a means of pinpointing stenotic or occluded arteries and defining optimal sites for the origin and termination of bypass grafts. We evaluated whether a duplex ultrasound scan, used as an alternative to arteriography, could be used as a means of accurately predicting the proximal and distal anastomotic sites in patients requiring peripheral bypass grafts and, therefore, replace standard preoperative arteriography. METHODS: Forty-one patients who required infrainguinal bypass grafts underwent preoperative duplex arterial mapping (DAM). Based on these studies, an observer blinded to the operation performed predicted what operation the patient required and the best site for the proximal and distal anastomoses. These predictions were compared with the actual anastomotic sites chosen by the surgeon. RESULTS: Whether a femoropopliteal or an infrapopliteal bypass graft was required was predicted correctly by means of DAM in 37 patients (90%). In addition, both anastomotic sites in 18 of 20 patients (90%) who had femoropopliteal bypass grafts and 5 of 21 patients (24%) who had infrapopliteal procedures were correctly predicted by means of DAM. CONCLUSION: DAM is a reliable means of predicting whether patients will require femoropopliteal or infrapopliteal bypass grafts, and, when a patient requires a femoropopliteal bypass graft, the actual location of both anastomoses can also be accurately predicted. Therefore, DAM appears able to replace conventional preoperative arteriography in most patients found to require femoropopliteal reconstruction. Patients who are predicted by means of DAM to require crural or pedal bypass grafts should still undergo preoperative contrast studies to confirm these results and to more precisely locate the anastomotic sites. 相似文献
148.
Building material characterization from complex transmissivity measurements at 5.8 GHz 总被引:1,自引:0,他引:1
An improvement of the well-known internal multireflection model of transmission coefficients is proposed in order to obtain better agreement with complex measured data. The reason for the introduced changes is explained. To obtain the data, measurements were performed at 5.8 GHz using a vector network analyzer, which provided information on the amplitude and phase of the transmission coefficient. By comparing the model and measurements, both the real and imaginary parts of the material complex permittivity were estimated for four different building materials. 相似文献
149.
150.