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81.
High-mobility Ga0.47In0.53As thin epitaxial layers grown by MBE, very closely lattice-matched to InP
Massies J. Rochette J. Delescluse P. Etienne P. Chevrier J. Linh Nuyen T. 《Electronics letters》1982,18(18):758-760
Thin epitaxial layers (< 1.5 ?m) of Ga0.47In0.53As were grown by molecular beam epitaxy, very closely lattice-matched to InP, despite a nonrotating substrate holder. Hall mobilities were measured as a function of temperature in the dark and on illumination. At low temperature, the peak mobility of undoped layers lies between 35000 and 40000 cm2V?1s?1 in the dark and increases up to 45000 cm2V?1s?1 when measured in the light. Preliminary results obtained on slightly Sn-doped layers are also reported. 相似文献
82.
B Jaulhac M Reyrolle YK Sodahlon S Jarraud M Kubina H Monteil Y Piémont J Etienne 《Canadian Metallurgical Quarterly》1998,36(7):2120-2122
A prospective study was conducted on 25 Legionella pneumophila culture-positive and 98 culture-negative bronchoalveolar lavage fluid samples to compare two DNA preparation methods: a rapid modified Chelex-based protocol and a proteinase K method. PCR was found to be more sensitive with the Chelex-based method (P = 0.03). N difference was found concerning the inhibition rate. 相似文献
83.
Carmen Concelln Nicolas Duguet AndrewD. Smith 《Advanced Synthesis \u0026amp; Catalysis》2009,351(17):3001-3009
Chiral N‐heterocyclic carbenes (NHCs) mediate the enantioselective addition of 2‐phenylphenol to unsymmetrical alkylarylketenes, delivering α‐alkyl‐α‐arylacetic acid derivatives with good levels of enantiocontrol (up to 84% ee). Enantiodivergent stereochemical outcomes are observed using 2‐phenylphenol and benzhydrol in the NHC‐promoted esterification reaction using a triazolium precatalyst derived from pyroglutamic acid, consistent with distinct mechanistic pathways operating within these processes. 相似文献
84.
Ali Alaeldine Nicolas Lacrampe Richard Perdriau Fabrice Caignet Etienne Sicard 《Microelectronics Journal》2008,39(12):1728-1735
This paper presents a comparative study of susceptibility reduction techniques for electromagnetic interference (EMI) in digital integrated circuits (ICs). Both direct power injection (DPI) and very-fast transmission-line pulsing (VF-TLP) methods are used to inject interference into the substrate of a single test chip. This IC is built around six functionally identical cores, differing only by their EMI protection strategies (RC protection, isolated substrate, meshed power supply network) which were initially designed for low emission design rules. The ranking of three of these cores in terms of electromagnetic immunity is then compared with the one of their radiated emission, thanks to near-field scanning (NFS) measurements. This leads to the establishing of design guidelines for low EMI in digital ICs. 相似文献
85.
Etienne Perret Nicolas Zerounian Sylvain David Frédéric Aniel 《Microelectronic Engineering》2008,85(11):2276-2281
High-quality polymers such as the benzocyclobutene polymer (BCB) provide interesting dielectric feature for terahertz applications. Already used in silicon integrated circuit technologies, this material could become one of the most promising candidates for the realization of future THz waveguides and interconnections on a silicon substrate but also after active devices process on the top of any other technology (GaAs, InP, GaN…). A frequency-dependent complex permittivity of spin-coated thick layers of this low-k dielectric is obtained from transmittance spectra measured with Fourier transform spectroscopy in the frequency range of 0.5-5.4 THz. The dielectric constant and the loss tangent are discussed according to curing conditions of the photosensitive resin used. A low loss tangent value of 7 − 9 × 10-3 at 1 THz is obtained with polymerisation in oxygen-free atmosphere. An incomplete curing and a high dose UV exposure have a weak impact on losses. These results associated with the high compatibility of this polymer with silicon and metals make BCB layers well suited for the design of microelectronic THz devices and circuits. 相似文献
86.
Isabelle Déléris Anne Saint-Eve Fanny Dakowski Etienne Sémon Jean-Luc Le Quéré Hervé Guillemin Isabelle Souchon 《Food chemistry》2011
We investigated the role of both candy texture and eating technique (melting or chewing) on the dynamics of aroma release. One novelty of this type of analysis was the simultaneous application of instrumental and sensory analysis. Four candy textures were established based on their storage modulus at 1 Hz by varying the gelatine content between 0 and 15% w/w. The invivo release of three aroma compounds was monitored using Proton Transfer Reaction Mass Spectrometry and with a trained panel of testers. The gelatine content had no significant effect on the headspace/product partition and diffusion properties of the aroma compounds. The highest invivo release for all aroma compounds was obtained with the 2% gelatine sample. Our findings indicated that aroma release was determined by interaction between the product properties and oral behaviour. Relations between the dynamics of release and perception (method of Temporal Dominance of Sensations) have been established on temporal parameters. 相似文献
87.
The combination of oxaliplatin (LOHP)-5-fluorouracil (FU)-folinic acid (FA) has provided high response rates in pretreated patients with advanced colorectal cancer that is resistant to FU-FA. However, the choice of the optimal schedule between LOHP, FU, and FA remains open. The purpose of the present study was to compare, at equivalent drug area under the curve, different schedules for the LOHP-FU +/- FA combinations on four human colorectal cancer cell lines. FU +/- FA was tested as a 2-h short exposure ("bolus"), a 118-h continuous exposure ("infusion"), or a 22-h mixed exposure ("De Gramont protocol"). LOHP was administered for 2 h before, during, or after FU +/- FA exposure. Isobologram analyses revealed that LOHP associated with FU +/- FA resulted in synergistic cytotoxic effects whatever the tested schedules (in > or = 75% of cases). For the FU-LOHP combination, cytotoxicity was significantly different according to the FU exposure type (short > mixed > continuous) and was independent of the LOHP position. In contrast, for the FU-FA-LOHP combination, neither the FU exposure type nor the LOHP position significantly influenced cytotoxicity. The presence of FA significantly enhanced the cytotoxicity of FU-LOHP (P < 0.001); this potentiation was independent of the FU exposure type and was significantly influenced by the LOHP position (LOHP after FU-FA > LOHP during FU-FA > LOHP before FU-FA). In conclusion, in contrast with the recognized superiority of continuous FU exposure over short exposure when the drug is given alone, the FU-LOHP combination is more cytotoxic when FU is given as a short exposure. This suggests the potential interest of such a schedule in the clinical setting. 相似文献
88.
Frédéric Soulignac Pierre-Alain Danis Damien Bouffard Vincent Chanudet Etienne Dambrine Yann Guénand Tristan Harmel Bastiaan W. Ibelings Dominique Trevisan Rob Uittenbogaard Orlane Anneville 《Journal of Great Lakes research》2018,44(4):756-764
Lake biological parameters show important spatio-temporal heterogeneities. This is why explaining the spatial patchiness of phytoplankton abundance has been a recurrent ecological issue and is an essential prerequisite for objectively assessing, protecting and restoring freshwater ecosystems. The drivers of these heterogeneities can be identified by modeling their dynamics. This approach is useful for theoretical and applied limnology. In this study, a 3D hydrodynamic model of Lake Geneva (France/Switzerland) was created. It is based on the Delft3D suite software and includes the main tributary (Rhône River) and two-dimensional high-resolution meteorological forcing. It provides 3D maps of water temperature and current velocities with a 1?h time step on a 1?km horizontal grid size and with a vertical resolution of 1?m near the surface to 7?m at the bottom of the lake. The dynamics and the drivers of phytoplankton heterogeneities were assessed by combining the outputs of the model and chlorophyll-a concentration (Chl-a) data from MERIS satellite images between 2008 and 2012. Results highlight physical mechanisms responsible for the occurrence of seasonal hot-spots in phytoplankton abundance in the lake. At the beginning of spring, Chl-a heterogeneities are usually caused by an earlier onset of phytoplankton growth in the shallowest and more sheltered areas; spatial differences in the timing of phytoplankton growth can be explained by spatial variability in thermal stratification dynamics. In summer, transient and locally higher phytoplankton abundances are observed in relation to the impact of basin-scale upwelling. 相似文献
89.
90.
In their article ( https://doi.org/10.1002/adfm.201703511 ), Bojnicic‐Kninski et al. expose the known methods used for creating, on a same substrate, patterns composed of different types of particles. This approach is called “combinatorial particle patterning.” They describe various techniques and group them depending on the used methods or driving forces that enable the directed assemblies of particles. A substantial part of the article (Part 2: Electrical Particle Patterning) referred to particle assemblies guided by electrostatic forces, i.e., electrophoretic or dielectrophoretic forces. However, this part, especially the paragraph on “Nanoxerography” (cf. 2.2 of the article) suffers from some inaccuracies that lead to partially wrong conclusions regarding combinatorial particle patterning. The goal of this comment is double: i) giving a complete and up to date definition of nanoxerography ii) reporting the results on combinatorial particle patterning using nanoxerography to correct the article inaccuracies. 相似文献