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101.
Miniaturization is the main goal for system design in future cameras. This paper offers a novel method to scale down the optical system and to improve the image quality. As with the human retina, the detector array is spherically bent to fit the curved image surface; so the field curvature aberration is directly suppressed, leading to a better resolution and a simplified optical design. By thinning the substrate, the device is monolithically curved without modifying the fabrication process of the active pixels. Optical characterizations have been performed on planar and curved focal plane based cameras to illustrate the optical advantages of detector array curvature. 相似文献
102.
Hoël Langouët Ludovic Métivier Delphine Sinoquet Quang-Huy Tran 《Optimization and Engineering》2011,12(3):407-424
We present two new approaches to address the optimization problem associated with engine calibration. In this area, the tuning parameters are traditionally determined in a local way, i.e., at each engine operating point, via a single-objective minimization problem. To overcome these restrictions, the first method we propose is able to cope with several objective functions simultaneously in the local formulation. The second method we put forward relies on a global formulation, which allows the whole driving cycle to be taken into account while remaining single-objective. At the practical level, the two methods are implemented by combining various existing techniques such as the LoLiMoT (Local Linear Model Tree) parameterization and the MO-CMA-ES (Multi-Objective Covariance Matrix Adaptation Evolution Strategy) algorithm. A better compromise appears to be achieved on real case applications. 相似文献
103.
Claudia Gordin Christelle Delaite Hussein Medlej Delphine Josien-Lefebvre Kamal Hariri Mihai Rusu 《Polymer Bulletin》2009,63(6):789-801
We described the obtention of well-defined ABC star block copolymers through the use of a new heterotrifunctional initiator.
That way, well-defined PCL-arm–PS-arm–PLLA star block copolymers have been synthesized from a heterotrifunctional initiator
bearing two hydroxyl groups able to initiate ROP of CL and LLA (using Sn(Oct)2 as coinitiator) and a bromide function able to initiate ATRP of styrene. 相似文献
104.
Delphine Meunier Sedat Tardu Dimitrios Tsamados Jumana Boussey 《Microelectronics Journal》2003,34(12):1129-1136
In this paper we present the impact of hot wire geometry and fluid characteristics on the efficiency of a hot wire to be used as a wall shear stress sensor. Finite differences and finite elements modelling based simulators were used in order to evaluate the thermal performances of hot wire wall shear stress sensor. Several structures were explored including simple conductor or suspended above a cavity (free and sealed with an oxide membrane). It is found out that wire length, wire section and the dimensions of the micro-cavity lying below the hot wire are of fundamental importance on the thermal exchanges occurring between the hot wire and the fluid. 相似文献
105.
In this paper, the actuator‐in‐actuator cylinder (AC‐squared) model is presented. This model is an extension of the original actuator cylinder model of Madsen and is capable of modelling the effect of a two concentric actuation surfaces in 2D. The induced velocity at every point in the 2D field is affected by the force field acting on the two actuator cylinders. The equations are derived, and a model verification is performed using analytical solutions of flows, proof of flow equivalence, and using OpenFOAM calculations. Finally, the model is applied to different case studies, and the results are compared with a time‐dependent free wake vortex method. 相似文献
106.
107.
108.
Biological Functions and Metabolism of Oleoylethanolamide 总被引:2,自引:0,他引:2
Thabuis C Tissot-Favre D Bezelgues JB Martin JC Cruz-Hernandez C Dionisi F Destaillats F 《Lipids》2008,43(10):887-894
The present review is focused on the metabolism and the emerging roles of oleoylethanolamide (OEA) with emphasis on its effects on food intake control and lipid metabolism. The biological mechanism of action, including a non-genomic effect mediated through peroxisome proliferator-activated receptor alpha (PPAR-alpha) and transient receptor potential vanilloid type 1 (TRPV1) receptor, is discussed. The research related to fatty acid ethanolamides has been focused until recently on anandamide and its interaction with cannabinoid receptor subtype 1. The roles of other N-acyl ethanolamine fatty acid derivatives have been neglected until it was demonstrated that OEA can modulate food intake control through interaction with PPAR-alpha. Further investigations demonstrated that OEA modulates lipid and glucose metabolism, and recent study confirmed that OEA is an antagonist of TRVP1. It has been demonstrated that OEA has beneficial effects on health by inducing food intake control, lipid beta-oxidation, body weight loss and analgesic effects. The investigation of the mechanism of action revealed that OEA activates PPAR-alpha and stimulates the vagal nerve through the capsaicin receptor TRPV1. Pre-clinical studies showed that OEA remains active when administered orally. 相似文献
109.
European corn borer larvae detect and avoid feeding in the presence of phytoecdysteroids (PEs) such as 20-hydroxyecdysone
(20E). Therefore, we hypothesized that females would have taste receptors similar to larvae and avoid laying eggs in the presence
of 20E. We found female-specific taste sensilla on the tarsi that respond to 20E at concentrations as low as 10−6 M, a threshold comparable to that of larvae. However, in choice tests, females laid a similar number of eggs on 20E-treated
and on nontreated artificial substrates (filter paper, glass, and nylon), although they spent significantly more time in behavioral
sequences related to substrate assessment when 20E was present. In contrast, when given a choice between maize plants (eight
leaves) sprayed with 20E or only the solvent, females laid 70% fewer eggs on the treated than on control plants. These observations
suggest that other chemical cues of plant origin must be present at the same time as 20E for females to modify their oviposition
behavior. 相似文献
110.
Substrate specificity of the acyltransferase activity of the lipase (EC 3.1.1.3) fromCandida parapsilosis CBS 604 was studied in aqueous media. The specificity toward both acid and alcohol parts of a large number of acylglycerols
and aliphatic esters was investigated. This lipase showed a high activity in the presence of esters with long-chain fatty
acids and particularly unsaturated fatty acids with acis-Δ9 double bond. It was observed that the activity profile depended not only on the alcohol part of the acyl ester, but also
on the temperature of the reactant medium. The best lipid substrates had their melting point between −40 to +20°C, 14 to 18
carbon atoms in the acyl group and 1 to 4 carbon atoms in the alkyl group. The enzyme, defined as an acyltransferase in a
previous paper, showed a high affinity for primary and secondary alcohols with a short carbon chain (1 to 5 carbon atoms)
as acyl acceptors. The influence of free alcohols in the reactant medium on the hydrolysis and alcoholysis activities of the
enzyme is discussed. Two phenomena seem to be involved, depending on the alcohol: competition with water for the acyltransfer
reaction and lipid substrate dilution when the alcohol places at the oil/water interface. 相似文献