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21.
To examine interactions between color and word attributes, participants responded, either manually or vocally, to a central target (color patch or word) flanked by a Stroop stimulus. Color and word attributes of the flanker affected both vocal and manual responding to color patches. Color and word flankers also affected manual responding to word targets, but only word flanker affected vocal responding to word targets. These results are not consistent with models (e.g., translational models) of Stroop tasks, which posit that interactions between colors and words occur only when vocal responding is required. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Computational Fluid Dynamics simulations of the thermodiffusion in high pressure ternary hydrocarbon mixtures of methane, n-butane and n-dodecane subject to micro-vibrations at reduced gravity are presented. Micro-gravity investigations of mixtures at such high pressures are unprecedented. The simulations indicate a formation of a single convective cell in all the mixtures due to a steady static micro-gravity in the x and y directions, and a stronger velocity component orthogonal to the direction of the temperature gradient. The consequent separation behavior of methane and n-dodecane in terms of the concentration profiles as well as the thermodiffusion coefficients was in agreement with the experimental trends. Also, as in the experiments, the change in the sign of the thermodiffusion coefficient of n-butane was correctly predicted. Small discrepancy was observed in the concentration profile of n-butane and is due to the under prediction of the thermodiffusion coefficients by the current thermodiffusion model as well as the displacement of small traces of n-butane via the bulk flow of n-dodecane.  相似文献   
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A series of experiments was carried out on different samples of tap water abstracted from the Baghdad water supply network in order to observe the effect of water on supply pipes, either scale forming or corrosive. This experimental investigation on the corrosive effect of the city of Baghdad tap water showed that the water can be classified as corrosive according to the Ryznar index, while the Langelier index showed that the water has the ability to form scale on the pipes. However, personal field observation indicated that the water is corrosive to the pipes and to the network appurtenance. Other findings are reported herein.  相似文献   
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This article focuses on the manufacture and usage of selected sheet metal objects from helmets, a vessel, and two shields from the European Bronze Age and Early Iron Age, which date from the thirteenth to seventh centuries BC. Manufacturing traces on the surface, as well as metallographic investigations and the analyses of the alloy composition with scanning electron microscope–energy-dispersive x-ray spectroscopy, provided an insight into the manufacturing techniques and the production of valuable, high-status objects, and highlighted the potential changes in manufacturing techniques and alloys used during different time periods.  相似文献   
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In this paper the performance of a low temperature, 50–70 C, solar boiler is presented. The boiler consisted of a double-glazed flat-plate solar collector, a flash chamber, a water cooled surface condenser, a circulating pump, and a temperature-controlled preheater to simulate constant temperature thermal storage. Data were obtained on this boiler from October 1980 to May 1981. During this period, the instantaneous total incident solar radiation at noon, as measured by a pyranometer in the plane of the collector ranged from 0.7 to 1.0 kWm-2 and the diurnal total incident solar radiation ranged from 13 to 29 MJ m-2day-1. At these conditions the instantaneous efficiency of the collector ranged from 30 to 55 percent while the diurnal efficiency ranged from 20 to 44 percent.The results show that the performance of the solar collector was the dominant factor in determining the performance of this boiler. They also show that low temperature steam, 50 to 70 C, from such boilers can be produced to drive multieffect distillation systems using high performance evaporators for desalting saline water.  相似文献   
28.
Materials based on PVDF with desirable and controllable features were successfully developed. The chemistry and roughness were adjusted to produce membranes with improved transport and separation properties. Membranes were activated using the novel piranha approach to generate OH-rich surfaces, and finally furnished with epoxy and long-alkyl moieties via stable covalent attachment. The comprehensive materials characterization provided a broad spectrum of data, including morphology, textural, thermal properties, and wettability features. The defined materials were tested in the air-gap membrane distillation process for desalination, and improvement compared with pristine PVDF was observed. An outstanding behavior was found for the PVDF sample equipped with long-alkyl chains. The generated membrane showed an enhancement in the transport of 58–62% compared to pristine. A relatively high contact angle of 148° was achieved with a 560 nm roughness, producing a highly hydrophobic material. On the other hand, it was possible to tone the hydrophobicity and significantly reduce adhesion work. All materials were highly stable during the long-lasting separation process and were characterized by excellent effectiveness in water desalination.  相似文献   
29.
Virtual software execution environment, known as Virtual Machine (VM), has been gaining popularity through Java Virtual Machine (JVM) and Common Language Infrastructure (CLI). Given their advantages in portability, productivity, and safety, etc., applying VM to real-time embedded systems can leverage production cost, fast time-to-market, and software integrity. However, this approach can only become practical once the VM operations and application tasks are made schedulable jointly. In this paper, we present a schedulable garbage collection algorithm applicable on real-time applications in CLI virtual machine environment. To facilitate the scheduling of real-time applications and garbage collection operations, we make the pause time due to garbage collection controllable, and the invocation of garbage collection predictable. To demonstrate the approach, a prototype for a schedulable garbage collection has been implemented in CLI execution environment. The garbage collection is carried out by a concurrent thread while meeting a targeted pause time and satisfying the memory requests of applications. A cost model of garbage collection is established based on measured WCET such that the execution time and overhead of garbage collection operations can be predicted. Finally, we illustrate a joint scheduling algorithm to meet the time and memory constraints of real-time systems.  相似文献   
30.
The design of shape memory alloys (SMAs) structures against fatigue requires the computation of the stabilized mechanical state. The classical computation method, based on a plasticity-like algorithm, requires a step-by-step calculation, leading to prohibitive computation time to reach this stabilized state. To overcome this issue, we propose to extend the direct cyclic method (DCM), for elastoplastic structures, for use with the Zaki-Moumni (ZM) model for SMAs. DCM is a large time increment method in which a periodicity condition is enforced on the state variables. Comparison with the classical incremental approach shows considerable reduction in computation time.  相似文献   
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