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51.
Two monoclonal antibodies (mAb) within cluster M4 of the myeloid section of the Second International Swine CD Workshop, C4 (No. 144) and PM18-7 (No. 192), showed reactivity with thymocytes and among cells of myelomonocytic origin with mature macrophages but not with monocytes and granulocytes. Both mAb recognize a protein showing two bands of 205 kDa and 130 kDa under both reducing and non-reducing conditions. Although epitope mapping with these mAb could not be performed, this cluster received the SWC9 designation.  相似文献   
52.
We study the problem of designing a feedback controller for a highly flexible Euler-Bernoulli beam using a distributed-parameter H-method. Employing skew Toeplitz theory, we derive the H-optimal controller for a weighted mixed sensitivity design for the beam. Based on the structure of the optimal controller we obtain suboptimal, finite-dimensional, linear, time-invariant controllers. With this approach we are able to include the added difficulties of a pure time delay and a noncollocated actuator/sensor pair directly into the design process.  相似文献   
53.
This paper presents a review of the latest developments on phase change materials (PCMs) for thermal energy storage (TES) applications in buildings. The paper provides information about material requirements for TES, classification of PCM, mathematical modelling and applications of PCMs.  相似文献   
54.
This article presents a modelling method of the signal delays induced by microelectronic interconnections regarding RL impedance load. The method proposed is based on the RLC model of the transmission lines (TL) extracted from the equivalent S parameters. Formulation for estimating the interconnection propagation delay is established according to the behaviour of the TL unit step responses. The second order model is validated with a microstrip interconnect prototype with simulations and measurements in frequency and time domains. The developed propagation delay model was validated with SPICE computations. For that, a transient simulation was performed by considering input signals corresponding to high‐speed data of some Gbits/s. Then, accurate results were found for interconnections with different lengths in order of millimetre and also by varying the load values. It was shown that the computed 50% propagation delays present of relative errors about 5%. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
55.
A dynamic velocity at the n-p junction interface has been introduced. Solar cell structures have been used as diode models. The relationship of the dynamic velocity with the technological parameters of solar cells and with the junction operating conditions has been considered. The variations of this dynamic velocity with the potential at the junction point out the influence of the base doping level and of the base width, and allow to differentiate the nature of the cell back contact.  相似文献   
56.
57.
The specific heats of ThP and the solid solution UP0.5As0.5 have been measured in the temperature range 5–300 K. While ThP has a regularC p (T) behavior, the mixed compound exhibits several low-temperature anomalies. An analysis of the experimental data for UP0.5As0.5 and reanalysis of previously published heat capacity results for UP have been performed. The temperature dependence of the magnetic entropy, which at 300 K reaches a value close toR ln 4 for both species, confirms the U3+ state for uranium atoms in these compounds. The value of the electronic heat capacity coefficient p in the paramagnetic state has also been extracted from the experimental data. It is far smaller than the respective low-temperature value (0).  相似文献   
58.
Studies related to severe core accidents constitute a crucial element in the safety design of Gen‐IV systems. A new experimental program, related to severe core accidents studies, is proposed for the zero‐power experimental physics reactor (ZEPHYR) future reactor. The innovative program aims at studying reactivity effects at high temperature during degradation of Gen‐IV cores by using critical facilities and surrogate models. The current study introduces the European lead‐cooled system (ELSY) as an additional Gen‐IV system into the representativity arsenal of the ZEPHYR, in addition to the sodium‐cooled fast reactors. Furthermore, this study constitutes yet another step towards the ultimate goal of studying severe core accidents on a full core scale. The representation of the various systems is enabled by optimizing the content of plutonium oxide in the ZEPHYR fuel assembly. The study focuses on representing reactivity variation from 900°C at nominal state to 3000°C at a degraded state in both ELSY and Advanced Sodium Technological Reactor for Industrial Demonstration (ASTRID) cores. The study utilizes the previously developed calculation scheme, which is based on the coupling of stochastic optimization process and Serpent 2 code for sensitivity analysis. Two covariance data are used: the ENDF 175 groups for ELSY and the Covariance Matrix Cadarache (COMAC) 33 groups for ASTRID. The effect of the energy group structure of the covariance data on the representativity process is found to be significant. The results for single degraded ELSY fuel assembly demonstrate high representativity factor (>0.95) for reactivity variation and for the criticality level. Also, it is shown that the finer energy group structure of the covariance matrices results in dramatic improvement in the representation level of reactivity variations.  相似文献   
59.
Pharmaceuticals have recently emerged as novel pollutants of potential concern in the aquatic environment where they are commonly introduced as complex mixtures via municipal effluent. In the present experiment, the freshwater cnidarian Hydra attenuata was exposed to a mixture of 11 pharmaceuticals (ibuprofen, naproxen, gemfibrozil, bezafibrate, carbamazepine, sulfapyridine, oxytetracycline, novobiocin, trimethoprim, sulfamethoxazole and caffeine) up to 10 000 times (×) the concentration found in municipal effluent. Hydra regeneration and teratogenicity was measured, having an IC50 of 781× and was found to be non teratogenic with an A/D value of ∼ 1. Toxicity was investigated using both lethal (based on morphology) and sub-lethal (based on morphology, feeding behaviour, hydranth number and attachment) endpoints. The pharmaceutical mixture incurred a significant decrease in morphology at 0.1, 10 and 100× but a significant increase at 1000×. All parameters were significantly reduced at 10 000×. An EC50 of 425× and 65× based on morphology and feeding respectively and a toxicity threshold (TT) of 3.2× were calculated. When compared to the toxicity of each pharmaceutical exposed individually as previously reported [Quinn B, Gagné F, Blaise C. An investigation into the acute and chronic toxicity of eleven pharmaceuticals found in wastewater effluent on the cnidarian, H. attenuata. Sci Total Environ 2008a; 389: 306-314], the compounds in the mixture were present at concentrations 2 to 3 orders of magnitude lower for the equivalent toxicity (EC50 and TT). These results indicate that pharmaceuticals act additively in a mixture, having sub-lethal effects at environmentally relevant (µg/L-ng/L) concentrations and that their combined concentrations could potentially prove significantly ecotoxic to Hydra and possibly to other aquatic taxa.  相似文献   
60.
In biological architectures, material properties are optimized by the hierarchical structuring of components with a multiscaled order, from the nano‐ to the macroscales. Such designs enable, for instance, programmed yield points that maximize toughness. However, research efforts in biomimetic materials have focused on the assembly of nano‐ or macrostructures individually. In this study, high strength cellulose nanocrystals (CNCs), assembled into chiral‐nematically ordered structures, are tiled into a higher level, macro‐sized, architecture by topographical templating. As templates, two meshed architectures with distinct feature sizes are evaluated, and the optomechanical properties of the resulting films are compared to featureless, flat, CNC films. Controlling capillary stresses arising during CNC assembly is shown to enable control over the orientation of the chiral‐nematic director across the topography of the template. Tuning the specific reflections and multiscaled fracture propagation is demonstrated for the microtemplated CNC films. The latter phenomenon contributed to enhancing the toughness of the material through a high tortuosity of fracture propagation in all (x, y, z) directions. The presented findings are expected to pave the way towards the incorporation of current research in cellular metamaterials with the research focusing on the generation of nanoscaled biomimetic constructs.  相似文献   
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