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101.
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Esa Toukoniitty Johan Wärnå Dmitry Yu. Murzin Tapio Salmi 《Chemical engineering science》2010,65(3):1076-1087
Transient techniques are frequently used for catalytic gas-phase processes, but the application of transient techniques on catalytic three-phase systems is very scarce. Transient kinetic experiments provide valuable additional information about the behaviour of complex organic reaction systems, which was illustrated here with continuous enantioselective three-phase hydrogenation of ethyl benzoylformate over supported Pt catalyst particles in a fixed bed. The catalyst stability and the details of the adsorption–desorption behaviour of the reaction participants were revealed by transient experiments. Quantitative modelling of the data was based on kinetic experiments and characterisation of the reactor flow pattern by an inert tracer. Both liquid-phase species and adsorbed surface species were included in the modelling. The model predicted correctly the dynamic behaviour of the complex organic system under transient conditions. The approach is generally applicable to complex organic systems undergoing catalytic transformations. 相似文献
104.
Tatiana A. Kolesnikova Dmitry A. Gorin Paulo Fernandes Stefanie Kessel Gennady B. Khomutov Andreas Fery Dmitry G. Shchukin Helmuth Möhwald 《Advanced functional materials》2010,20(7):1189-1195
A water suspension of nanocomposite microcapsules with embedded ZnO nanoparticles in the capsule shell is reported. The microcapsule morphology is characterized by confocal microscopy, TEM, SEM, and AFM before and after ultrasound treatment. A remarkably high capsule sensitivity to ultrasound is evidenced, and it is observed to grow with increasing number of ZnO nanoparticle layers in the nanocomposite shell. This effect is correlated with the mechanical properties of microcapsules measured with AFM. 相似文献
105.
Constantin Turta Silvia Melnic Denis Prodius Fliur Macaev Helene Stoeckli-Evans Patricia Ruiz Dmitry Muraviev Serghei Pogrebnoi Zinaida Ribkovskaia Valeriu Mereacre Yanhua Lan Annie K. Powell 《Inorganic chemistry communications》2010,13(12):1402-1405
High-temperature solution phase reaction of iron(III)-furoate in sunflower oil, in the presence of trichloroacetic acid and 1,2-hexadecylamine leads to iron(III) oxide (amorphous and γ-Fe2O3) nanoparticles with sizes about 1.3 nm in diameter (method “A”), and about 5.5 nm (amorphous Fe2O3) from the “sunflower oil/oxadiazol” system (method “B”). 相似文献
106.
Yulia V. Gerasimova Dr. Aaron Hayson Jack Ballantyne Dr. Dmitry M. Kolpashchikov Dr. 《Chembiochem : a European journal of chemical biology》2010,11(12):1762-1768
Molecular beacon (MB) probes are dual‐labeled hairpin‐shaped oligodeoxyribonucleotides that are extensively used for real‐time detection of specific RNA/DNA analytes. In the MB probe, the loop fragment is complementary to the analyte: therefore, a unique probe is required for the analysis of each new analyte sequence. The conjugation of an oligonucleotide with two dyes and subsequent purification procedures add to the cost of MB probes, thus reducing their application in multiplex formats. Here we demonstrate how one MB probe can be used for the analysis of an arbitrary nucleic acid. The approach takes advantage of two oligonucleotide adaptor strands, each of which contains a fragment complementary to the analyte and a fragment complementary to an MB probe. The presence of the analyte leads to association of MB probe and the two DNA strands in quadripartite complex. The MB probe fluorescently reports the formation of this complex. In this design, the MB does not bind the analyte directly; therefore, the MB sequence is independent of the analyte. In this study one universal MB probe was used to genotype three human polymorphic sites. This approach promises to reduce the cost of multiplex real‐time assays and improve the accuracy of single‐nucleotide polymorphism genotyping. 相似文献
107.
Dmitry Pozdnyakov 《Journal of Computational Electronics》2014,13(1):338-351
As applied to the numerical simulation of electron transport and scattering processes in semiconductors an efficient model describing the scattering of electrons by the ionized impurities is proposed. On the example of GaAs at 77 and 300 K and Si at 300 K the dependencies of low-field electron mobility on the donor impurity concentration in the semiconductors are calculated in the framework of proposed model as well as in the framework of such most frequently used applied models as the Conwel-Weisskopf model and the Brooks-Herring one. After comparing the calculation results with the well-known experimental data it has been ascertained that the best agreement between the theory and experiment is achieved with application of the proposed model. 相似文献
108.
Henrik P. Porte Dmitry Turchinovich Saydulla Persheyev Yongchang Fan Mervyn J. Rose Peter Uhd Jepsen 《Journal of Infrared, Millimeter and Terahertz Waves》2011,32(7):883-886
Black silicon is produced by laser annealing of a-Si:H films. During annealing, silicon microstructures are formed on the
surface. We use time-resolved terahertz spectroscopy to study the photoconductivity dynamics in black silicon. We find that
when a copper film is deposited on top of the a-Si:H layer prior to laser annealing, the carrier lifetime of black silicon
is significantly reduced. 相似文献
109.
110.
Anatoly A. VostrikovOxana N. Fedyaeva Dmitry Y. DubovSergey A. Psarov Mikhail Y. Sokol 《Energy》2011,36(4):1948-1955
A study of conversion of organic matter of brown coal in supercritical water (SCW) at 30 MPa, 400−760 °C and continuous supply of coal-water slurry (CWS) into a tubular reactor is presented. It was found that 48−63% (depending on the SCW temperature) of coal organic matter (COM) is ejected from CWS coal particles as liquid and gaseous products when they move through the reactor. We termed this stage of SCW conversion as dynamic conversion (DC) of coal. It turns out that the particles which underwent the DC stage did not aggregate in the reactor during static conversion (SC) within a coal layer due to continuous pumping through this layer. The experimental data on the composition of DC and SC products, degree of coal conversion, and the data on the degree of combustion of carbon in the presence of oxygen are given. 相似文献