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771.
2,3‐Benzodiazepine derivatives : 1‐(4‐Aminophenyl)‐3,5‐dihydro‐3‐N‐ethylcarbamoyl‐5‐methyl‐7,8‐methylenedioxy‐4H‐2,3‐benzodiazepin‐4‐one was synthesized, and its enantiomers were separated by chiral HPLC. Pharmacological evaluation of each enantiomer showed that (S)‐(?)‐ 5 appears to be more potent than its optical antipode (R)‐(+)‐ 5 in an AMPA receptor binding assay.

  相似文献   

772.
Several laboratories monitoring for enteroviruses in wastewater have reported a high percentage of false-positive viral plaques. This article discusses the issue of possible false evaluation of viral plaque determinations in wastewater, and reviews the preventive measures taken in several wastewater studies conducted in our laboratory, which minimized this phenomenon. Our results showed that with the procedures described, no false-positive plaques were found.  相似文献   
773.
The decolouration and mineralization of reactive dye C.I. Reactive Black 5, a well-known representative of non-biodegradable azo dyes, by means of ultrasonic irradiation at 20, 279 and 817kHz has been investigated with emphasis on the effect of various parameters on decolouration and degradation efficiency. Characterization of the used ultrasound systems was performed using calorimetric measurements and oxidative species monitoring using Fricke and iodine dosimeter. Experiments were carried out with low frequency probe type, and a high-frequency plate type transducer at 50, 100 and 150W of acoustic power and within the 5-300mg/L initial dye concentration range. Decolouration, as well as radical production, increased with increasing frequency, acoustic power, and irradiation time. Any increase in initial dye concentration results in decreased decolouration rates. Sonochemical decolouration was substantially depressed by the addition of 2-methyl-2-propanol as a radical scavenger, which suggests radical-induced reactions in the solution. Acute toxicity to marine bacteria Vibrio fischeri was tested before and after ultrasound irradiation. Under the conditions employed in this study, no toxic compounds were detected after 6h of irradiation. Mineralization of the dye was followed by TOC measurements. Relatively low degradation efficiency (50% after 6h of treatment) indicates that ultrasound is rather inefficient in overall degradation, when used alone.  相似文献   
774.
The purpose of this paper is to establish the experimental conditions for removal of several textile dyes from aqueous solutions by sorption on beech wood sawdust, an industrial waste lignocellulosic product. From the six dyes tested, the sorbent shows preference for three dyes: Direct Brown, Direct Brown 2 and Basic Blue 86. Sorption of dyes on the beech wood sawdust is dependent on the nature of dye, pH, dyes concentration, contact time, and amount of sorbent. By comparative kinetic studies, the rate of sorption was found to conform with good correlation to pseudo-second-order kinetics. The parameters that characterize the sorption were determined on the basis of Langmuir isotherms. The preference of beech sawdust for dyes increases as follows: Basic Blue 86相似文献   
775.
We present a theoretical study of the lineup of the LUMO of Ru(II)-polypyridyl (N3 and N719) molecular dyes with the conduction band edge of a TiO(2) anatase nanoparticle. We use density functional theory (DFT) and the Car-Parrinello scheme for efficient optimization of the dye-nanoparticle systems, followed by hybrid B3LYP functional calculations of the electronic structure and time-dependent DFT (TDDFT) determination of the lowest vertical excitation energies. The electronic structure and TDDFT calculations are performed in water solution, using a continuum model. Various approximate procedures to compute the excited state oxidation potential of dye sensitizers are discussed. Our calculations show that the level alignment for the interacting nanoparticle-sensitizer system is very similar, within about 0.1?eV, to that for the separated TiO(2) and dye. The excellent agreement of our results with available experimental data indicates that the approach of this work could be used as an efficient predictive tool to help the optimization of dye-sensitized solar cells.  相似文献   
776.
This study presents field observations and numerical modeling of surface seiche formations on a shallow reservoir in a complex terrain (Rules Reservoir, Spain). The influence of the surrounding topography on the atmospheric loading (barometric pressure and wind speed) is investigated, with the associated atmospheric-hydrodynamic coupling. During a 13-day field study, maximum free surface oscillations of 4?cm were recorded after the passing of a short duration storm (<5??min), which included a peak wind gust of 22??m/s. Observations also present evidence of resonant excitation of the free surface caused by high-frequency microscale harmonics (<10??min) in the atmospheric forcing. Resonant excitation caused by harmonics in the atmospheric forcing is significant for small reservoirs situated in regions of complex terrain where topographical obstacles modify the flow patterns in the near-surface boundary layer, generating eddies with harmonics in the microscale range of the atmospheric forcing spectrum. Harmonics in the atmospheric forcing are observed for a range of periods (200–700?s) during the survey. Surface oscillations of 2?cm are generated when the frequency of the forcing matches the fundamental reservoir modal frequency, even for low wind speeds. A two-dimensional depth-integrated numerical model predicted the observed surface seiche formation in both cases.  相似文献   
777.
In this paper the theoretical and experimental aspects are described concerning the validation of a method for the measurement of the percentage composition of a generic liquid fuel, even though specific reference materials for instrumentation calibration are unavailable. This new method could be used for the evaluation of the Emission Factor (EF) of an unknown fuel for emission trading purposes, according to the requirements of both the juridical and technical standards. The validation of the procedure is based on the comparison of different techniques for the measurement of Gross Calorific Value (GCV), Net Calorific Value (NCV) which are quantities useful in EF evaluation; this new combination of actions established a complete and validated methodology for EF evaluation. The experimental results and uncertainty analysis show that this method is suitable for the estimation of the composition measurement and also that of GCV, NCV and EF also for non-standard liquid fuels; a comparable accuracy with respect to the methods for standard fuels has been estimated, making this method suitable for practical applications.  相似文献   
778.
The authors of this study investigated the behavioral and emotional response of female Japanese macaques (Macaca fuscata) to an aggression received by their offspring to evaluate the existence of cognitive empathic responses in a naturalistic setting. After their offspring received an aggression, mothers did not direct increased affiliative contacts to them. The factors likely to affect the degree of distress in the offspring or the perceived risk for the mother failed to appropriately modulate maternal behavior. Finally, mothers did not increase their frequency of scratching (a behavioral indicator of anxiety) after their offspring had received an aggression. The results suggest Japanese macaque mothers may be unable to understand their offspring's need for distress alleviation after the receipt of aggression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
779.
780.
We study a simple software architecture, in which components are coordinated by writing into and reading from a global set. This simple architecture is inspired by the industrial software architecture Splice. We present two results. First, a distributed implementation of the architecture is given and proved correct formally. In the implementation, local sets are maintained and data items are exchanged between these local sets. Next we show that the architecture is sufficiently expressive in principle. In particular, every global specification of a system's behaviour can be divided into components, which coordinate by read and write primitives on a global set only. We heavily rely on recent concepts and proof methods from process algebra.  相似文献   
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