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121.
Simultaneous planar laser-induced incandescence, hydroxyl radical planar laser-induced fluorescence, and droplet Mie scattering are used to study the instantaneous flame structure and soot formation process in an atmospheric pressure, swirl-stabilized, liquid-fueled, model gas-turbine combustor. Optimal excitation and detection schemes to maximize single-shot signals and avoid interferences from soot-laden flame emission are discussed. The data indicate that rich pockets of premixed fuel and air along the interface between the spray flame and the recirculation zone serve as primary sites for soot inception. Intermittent large-scale structures and local equivalence ratio are also found to play an important role in soot formation.  相似文献   
122.
Ballistic imaging of the liquid core for a steady jet in crossflow   总被引:2,自引:0,他引:2  
Linne MA  Paciaroni M  Gord JR  Meyer TR 《Applied optics》2005,44(31):6627-6634
A time-gated ballistic imaging instrument is used to obtain high-spatial-resolution, single-shot images of the liquid core in a water spray issuing into a gaseous crossflow. We describe further development of the diagnostic technique to improve spatial resolution and present images and statistics for various jets under crossflow experimental conditions (different Weber numbers). Series of these images reveal a near-nozzle flow field undergoing breakup and subsequent droplet formation by stripping. One can also detect signatures of spatially periodic behavior in the liquid core and formation of small voids during breakup.  相似文献   
123.
Pharmacologically isolated GABAergic irregular spiking and stuttering interneurons in the mouse visual cortex display highly irregular spike times, with high coefficients of variation approximately 0.9-3, in response to a depolarizing, constant current input. This is in marked contrast to cortical pyramidal cells, which spike quite regularly in response to the same current injection. We applied time-series analysis methods to show that the irregular behavior of the interneurons was not a consequence of low-dimensional, deterministic processes. These methods were also applied to the Hindmarsh and Rose neuronal model to confirm that the methods are adequate for the types of data under investigation. This result has important consequences for the origin of fluctuations observed in the cortex in vivo.  相似文献   
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125.
Unlocking the secrets of the brain is a task fraught with complexity and challenge – not least due to the intricacy of the circuits involved. With advancements in the scale and precision of scientific technologies, we are increasingly equipped to explore how these components interact to produce a vast range of outputs that constitute function and disease. Here, an insight is offered into key areas in which the marriage of neuroscience and nanotechnology has revolutionized the industry. The evolution of ever more sophisticated nanomaterials culminates in network‐operant functionalized agents. In turn, these materials contribute to novel diagnostic and therapeutic strategies, including drug delivery, neuroprotection, neural regeneration, neuroimaging and neurosurgery. Further, the entrance of nanotechnology into future research arenas including optogenetics, molecular/ion sensing and monitoring, and piezoelectric effects is discussed. Finally, considerations in nanoneurotoxicity, the main barrier to clinical translation, are reviewed, and direction for future perspectives is provided.  相似文献   
126.
Batch process monitoring methods, such as multiway PCA and multiblock multiway PLS, make use of process variable time profiles to normalize and define most likelihood trajectories for statistical process control. Nevertheless, a continuous process analytics counterpart has not been developed, nor addressed in the literature. This paper presents a novel methodology that defines “state variables” to determine the multiple operating points around which a continuous process operates. In this manner, the operating region is divided into multiple regions (states) and shifts in operating conditions are captured by such state variables. Transition trajectories between states are calculated to determine the most likely path from one state to another. This methodology is referred as multistate analytics and can be implemented in the context of empirical monitoring methods, named multistate PLS and multistate PCA. A case study using data from carbon dioxide removal process shows that multistate analytics is beneficial for statistical monitoring of continuous processes.  相似文献   
127.
When guinea pig pups are isolated for a few hours in a novel environment, they exhibit a distinctive passive behavioral response that appears to be mediated by proinflammatory activity. Recently, we observed that pups separated on two consecutive days show an enhanced (sensitized) passive response on the second day. In Experiment 1, pups receiving intracerebroventricular infusion of 50 ng of the anti-inflammatory cytokine interleukin-10 prior to a first separation failed to show a sensitized behavioral response to separation the next day. In Experiment 2, pups separated on Days 1 and 2, or just 2, showed an increase in passive responding during separation on Day 5. Pups injected with the bacterial antigen lipopolysacchride (LPS; 75 μg/kg body weight, intraperitoneal) prior to separation on Day 1 showed an increase in passive behavior several days later not shown by pups injected with saline prior to Day 1 separation. However, injection of LPS without separation on the first day did not enhance responding during an initial separation on the second day. These results suggest that immune activation is necessary, but not sufficient, to account for the sensitization of passive behavior of isolated guinea pig pups the following day, that boosting proinflammatory activity during an initial separation may promote sensitization several days later, and that the sensitized response persists for at least several days. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
128.
The electrical properties of Al2O3/n-InGaAs metal–oxide–semiconductor capacitors (MOSCAPs) with In content of 0.53, 0.7, and 1 (InAs) have been investigated. Results show small capacitance–voltage (CV) frequency dispersion in accumulation (1.70% to 1.85% per decade) for these MOSCAPs, mostly being assigned to border traps in Al2O3. With higher In content, shorter minority-carrier response time and smaller CV hysteresis are observed. The reduction of CV hysteresis might be related to the reduction of Ga-bearing oxides in Al2O3/InGaAs interfaces as indicated by x-ray photoelectron spectroscopy.  相似文献   
129.
Guided by the theory of planned behavior, this analysis explores the communication skills of women who had genetic testing for BRCA1 and BRCA2. The key outcome was intention to tell test results to adult first-degree relatives. The theory predicts that global and specific attitudes, global and specific perceived social norms, and perceived control will influence the communication of genetic test results. A logistic regression model revealed that global attitude (p  相似文献   
130.
Abstract

The problem of pattern classification when very little is known about the pattern source is structured through a set of axioms describing desirable properties for a classifier that involve no probabilistic assumptions or hypotheses. The derived classifier is then studied under the hypothesis that the pattern source is probabilistic and its long-run performance found to strongly converge to that of the Bayes classifier under reasonable restrictions. The sparse results of a pilot study on the comparative small sample performance of the derived classifier are found to be encouraging but not definitive. This work is an outgrowth of previous work on extrapolation when little is known  相似文献   
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