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991.
Pierre Bisiaux Caroline Lelandais-Perrault Anthony Kolar Filipe Vinci dos Santos Philippe Benabes 《Analog Integrated Circuits and Signal Processing》2018,94(3):427-447
This paper presents an ultra-low-power, bulk-driven, source-degenerated fully differential transconductor (FD-OTA), operating in subthreshold region. The source-degeneration (SD) and bulk-drive ensure linearity and rail-to-rail input swing. The flipped voltage follower and SD resistor perform V–I conversion in input core with power efficient class AB mode of operation. The reduction in open loop gain and gain bandwidth (GBW) of bulk-drive is compensated by applying partial positive feedback at diode connected MOSFET pair. The current gain from input core to output load side is set (1:1) in OTA1 and (1:4) in OTA2. The OTA2 offers increased transconductance and GBW whereas self-cascode load increases the output impedance and overall gain of the FD-OTAs. Both the input core and common source self-cascode load operate in class AB mode so these FD-OTAs provide enhanced slew rates. These OTAs have been employed to implement Biquadratic low-frequency Gm-C filter suitable for bio-signal applications. The proposed OTA2 has used dual supply voltage of ± 0.3 V and dissipates around 70 nW power and provides 62 dB FD-open loop gain with GBW of 7.73 kHz while driving the FD-load of 2 × 15 pF. The Cadence VIRTUOSO environment using UMC 0.18 µm CMOS process technology has been used to simulate the proposed circuit. The Simulation results verified fully differential total harmonic distortion of ? 72 dB, for 1.2 Vp–p signal at 200 Hz frequency in unity gain configuration with resistive degeneration of 1 MΩ for OTA1. 相似文献
992.
Pierre Fauchais Ghislain Montavon Michel Vardelle Julie Cedelle 《Surface & coatings technology》2006,201(5):1908-1921
Thermal spray processing is used to confer specific in-service properties to components via the production of a coating between 50 μm (minimum value) to a few millimeters thick. Thermal spray represents a global market of about 4.8 Billion Euros (i.e., ∼ US$5 billion) in 2004; 30% of which is European based. 50% of this activity is devoted to plasma spray processing with about 90% dedicated to direct current (DC) plasma torches. Several developments of new torch architectures, among which three-cathode torches, have evolved recently. However, most of the recent progress has been applied to conventional DC torches. The advances were related to two prime factors: (i) the development of industrial sensors permitting to diagnose the processes during spray operation (especially in-flight particle characteristics in terms of their surface temperature and velocity) and additionally the monitoring of the substrate and coating temperatures with the objective of controlling the operating parameters via a close-loop controller; (ii) the adaptation of plasma spray systems to manufacture nano-structured coatings via the development of suspension plasma spray and solution plasma spray. As well, there has been an enhanced understanding of the mechanisms controlling the coating formation and of the effects of the arc root fluctuations; thereby permitting a more robust process. This paper develops the above points by presenting focused examples. 相似文献
993.
Francius G Hemmerlé J Ohayon J Schaaf P Voegel JC Picart C Senger B 《Microscopy research and technique》2006,69(2):84-92
A homemade colloidal probe atomic force microscope was used to perform nanoindentation with a spherical probe of 5 microm in diameter, at different approach velocities in order to extract the Young's modulus, E0, of poly(L-lysine)/hyaluronan (PLL/HA) films. This parameter is of prime importance to control cellular adhesion. The films were either kept in their native form or cross-linked with a mixture of 1-ethyl-3-(3-dimethyl aminopropyl)carbodiimide (EDC) and N-hydrosulfosuccinimide (sulfo-NHS), where the EDC concentration was varied from 1 up to 100 mg mL(-1) (approximately from 5 to 500 mM). A model based on Hertz mechanics was used to account for the interactions between film and probe. It is shown that the Young's modulus varies with the approach velocity for the native (PLL/HA) films, whereas for cross-linked ones, E0 is independent from the velocity over the whole range investigated. It is found that for native films, E0 takes a value of 3 kPa at low approach velocities, a velocity domain that should be relevant in cellular adhesion processes. The Young's modulus increases with the EDC concentration used to cross-link the films and levels off at a value of about 400 kPa for EDC concentrations exceeding 40 mg mL(-1). Thus, it is possible by crosslinking PLL/HA films to control their elastic properties with the aim to alter their behavior as to the cellular adhesion. 相似文献
994.
HongGee Kim Olivier Gillia Pierre Dormus Didier Bouvard 《International Journal of Mechanical Sciences》2002,44(12):2523-2539
Near net shape forming of alumina powder by cold die pressing and pressureless sintering was investigated. From experimental data of triaxial compression test of alumina powder, a hyperbolic cap model with a critical state line was proposed for densification of alumina powder at room temperature. For pressureless sintering, the phenomenological model for densification and viscous behavior of alumina powder proposed by Kim and co-workers was used. The constitutive models were implemented into a finite element program (ABAQUS) to simulate densification of alumina powder under cold die pressing and pressureless sintering. Finite element results were compared with experimental data for density distribution and deformation of an alumina powder compact under cold die pressing and pressureless sintering. New conditions of compaction were then proposed to reduce the distortion of the sintered part. 相似文献
995.
996.
997.
Louis Donald Notemgnou Mouafo Florian Godel Laurent Simon Yannick J. Dappe Walid Baaziz Ulrich Nguétchuissi Noumbé Etienne Lorchat Marie-Blandine Martin Stéphane Berciaud Bernard Doudin Ovidiu Ersen Bruno Dlubak Pierre Seneor Jean-Francois Dayen 《Advanced functional materials》2021,31(9):2008255
Mixed-dimensional heterostructures formed by the stacking of 2D materials with nanostructures of distinct dimensionality constitute a new class of nanomaterials that offers multifunctionality that goes beyond those of single dimensional systems. An unexplored architecture of single electron transistor (SET) is developed that employs heterostructures made of nanoclusters (0D) grown on a 2D molybdenum disulfide (MoS2) channel. Combining the large Coulomb energy of the nanoclusters with the electronic capabilities of the 2D layer, the concept of 0D–2D vertical SET is unveiled. The MoS2 underneath serves both as a charge tunable channel interconnecting the electrode, and as bottom electrode for each v-SET cell. In addition, its atomic thickness makes it thinner than the Debye screening length, providing electric field transparency functionality that allows for an efficient electric back gate control of the nanoclusters charge state. The Coulomb diamond pattern characteristics of SET are reported, with specific doping dependent nonlinear features arising from the 0D/2D geometry that are elucidated by theoretical modeling. These results hold promise for multifunctional single electron device taking advantage of the versatility of the 2D materials library, with as example envisioned spintronics applications while coupling quantum dots to magnetic 2D material, or to ferroelectric layers for neuromorphic devices. 相似文献
998.
Zeineddine Ali Nafkha Amor Paquelet Stéphane Moy Christophe Jezequel Pierre Yves 《Journal of Signal Processing Systems》2021,93(1):113-125
Journal of Signal Processing Systems - Sample rate conversion (SRC) is ubiquitous and critical function of software defined radio and other signal processing systems (speech coding and synthesis,... 相似文献
999.
Shiyong Zhao Guangxu Chen Guangmin Zhou Li‐Chang Yin Jean‐Pierre Veder Bernt Johannessen Martin Saunders Shi‐Ze Yang Roland De Marco Chang Liu San Ping Jiang 《Advanced functional materials》2020,30(6)
Single‐atom catalysts (SACs) are attracting significant attention due to their exceptional catalytic performance and stability. However, the controllable, scalable, and efficient synthesis of SACs remains a significant challenge. Herein, a new and versatile seeding approach is reported to synthesize SACs supported on different 2D materials such as graphene, boron nitride (BN), and molybdenum disulfide (MoS2). This method is demonstrated on the synthesis of Ni, Co, Fe, Cu, Ag, Pd single atoms as well as binary atoms of Ni and Cu codoped on 2D support materials with the mass loading of single atoms in the range of 2.8–7.9 wt%. In particular, the applicability of the new seeding strategy in electrocatalysis is demonstrate on nickel SACs supported on graphene oxide (SANi‐GO), exhibiting excellent catalytic performance for electrochemical CO2 reduction reaction with a turnover frequency of 325.9 h?1 at a low overpotential of 0.63 V and high selectivity of 96.5% for CO production. The facile, controllable, and scalable nature of this approach in the synthesis of SACs is expected to open new research avenues for the practical applications of SACs. 相似文献
1000.
Colantonio Lorenzo Dehombreux Pierre Hajman Michal Verlinden Olivier 《Multibody System Dynamics》2022,55(3):267-291
Multibody System Dynamics - In this paper, we develop an adaptation of the LuGre friction model so as to allow the development of the friction force and its application in any directions on systems... 相似文献