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991.
Twenty different strawberry genotypes from phenolic compound content and genetic diversity have been investigated. Twelve phenolic derivatives in the strawberry fruit extracts, their total phenolic content (TPC) and their radical scavenging activity have been quantified.  相似文献   
992.
In the last 10 years, new paradigms for wireless networks based on human mobility have gained the attention of the research community. These paradigms, usually referred to as Pocket Switched Networks or Delay Tolerant Networks, jointly exploit human mobility and store-and-forward communications to improve the connectivity in sparse or isolated networks. Clearly, understanding the human mobility patterns is a key challenge for the design of routing protocols based on such paradigms. To this aim, we anonymously collected the positions of almost two thousand mobile phone users, spread over a metropolitan area greater than 200 km2 for roughly one month. Then, with a multi-disciplinary approach, we estimated the mobility patterns from the collected data and, assuming Wi-Fi connectivity, we inferred the contact events among the devices to evaluate the connectivity properties of a human mobility-enabled wireless network. In a nutshell, the contribution of the paper is threefold: (i) it confirms some of the results obtained in smaller environments, such as the power-law distribution for contact and inter-contact times, allowing us to estimate the distribution parameters with high statistical significance; (ii) it addresses the feasibility of the transmission opportunities provided by human mobility to build a city-wide connected network for different forwarding strategies classes; (iii) it shows uncovered characteristics of the connectivity properties of human mobility, such as the presence of the small world phenomenon in wide-scale experiments.  相似文献   
993.
994.
The UOP Merox? process is an efficient and economical catalytic process developed for the treatment of petroleum fractions to remove sulfur present as thiols or to directly convert thiols to less-objectionable disulfides. The key to this oxidation process is a metal-chelate redox catalyst which selectively catalyzes the oxidation of thiols with oxygen as the oxidant without causing undesirable oxidation of hydrocarbons. In this paper, we discuss the Merox? process and mechanisms by which the catalyst selectively oxidizes thiols. Additionally, we discuss the development of promoted thiol oxidation catalyst systems which eliminate the use of caustic media in the oxidation process.  相似文献   
995.
Saffron (Crocus sativus L.) is a spice used in the food industry in an ever increasing, partly due to consumer preference for natural products . Crocus sativus stigmas are converted into saffron spice by a dehydration treatment. The postharvest treatment of the stigmas, particularly the drying process, is critical to the quality of saffron as measured by the level of secondary metabolites. The aim of this project was to study the volatiles compounds in saffron that came from three different sites of the Maremma Grossetana (Grancia, Pari and Alberese) (Tuscan). The corms were grown both in the place of origin and in the province of Pisa. Fifteen compounds were detected, accounting from 92.3% to 97.8% of the total volatiles. The main characteristic volatile compounds of the dried stigmas saffron were safranal, isophorone, 4‐keto isophorone, γ‐pyronene, dihydrooxophorone. Differences were found in the composition of volatile compounds both based on the place of cultivation and in a function of time of dehydration.  相似文献   
996.
The growing level of complexity of modern embedded systems, which are increasingly distributed and heterogeneous, calls for new design approaches able to reconcile mathematical rigour with flexibility, user-friendliness and scalability. In the last few years, Timed Automata (TA) have emerged as a very promising formalism for the availability of very effective verification tools. However, their adoption in the industrial community is still slow. The reluctance of industrial practitioners is partly motivated by persistent concerns on the ease of use of this formalism, on the scalability of the verification process and on the quality of the feedback that the designer receives. In this paper, we discuss these issues by showing the application of the TA formalism on a case study of industrial complexity. We expose the generality of the approach, the efficiency of state of the art tools, but also the limitations in the semantics and in dealing with free design parameters.  相似文献   
997.
Resonating microplates appear as ideal candidates for microcantilever-based real-time biosensing, because their low planar aspect ratio allows for effectively large Q factors, even in highly viscous fluids like water and other biological liquids. Since, a complete analytical treatment of a plate vibrating in liquid is missing; a fully numerical approach is needed for an effective design of a microcantilever-based Lab-On-Chip, as well as for its correct operation. We here report on a three-dimensional finite element model for an accurate and general solution methodology of the Fluid–Structure interaction for a plate vibrating in a transverse flexural mode within a viscous fluid environment. The model directly allows extracting vibration mode shapes, frequencies and Q factors through an eigenfrequency analysis, thus avoiding time-consuming and time-dependent simulations. A benchmark with the available analytical results (that rely on the classical beam theory) and a comparison with experimental data on a fabricated microcantilever-based Lab-On-Chip confirm the accuracy and the reliability of our numerical calculations. The here proposed model works in a very general context, without limitations about the cantilever planar geometry and material, as well as about the shape of the fluid domain.  相似文献   
998.
A propagation programme for peaches and nectarines has been targeted to select genotypes having taste attributes such as high sugar levels and well-balanced sugar/acid ratios. The analytical measurements of some soluble sugars and nonvolatile acids were carried out using innovative analytical procedures based on fast and selective devices which require very little or no sample pre-treatment whatsoever. These devices have found a unique application in detecting fructose, glucose and malic acid for the improvement of fruit genetics.

The present study examines relationships between the analytical measurements of sugars and non-volatile acids and the sensory attributes (sweetness and sourness) of 21 peach and nectarine cultivars. Certain chemical parameters were correlated with the organoleptic acceptance of common commercial cultivars and recently introduced high and low-acid genotypes. Multivariate statistical analyses were found to be useful in describing the variability of the chemical and sensory parameters which characterise peach quality, as they enabled the identification of sets of variables that could be used to classify peaches and nectarines into high and low-acid categories. Malic and citric acids, minor components of these fruits, were important taste attributes as they contributed to the sensory perception of sourness.  相似文献   

999.
PURPOSE: To study accuracy and safety, related to sensation (discomfort) and trauma, when using Goldmann applanation tonometry (GAT) on eyes wearing daily disposable soft contact lenses. METHODS: The intra-ocular pressure (IOP) of 136 normal eyes of 68 subjects was measured by Goldmann tonometer. Measurements were made in one eye with a contact lens (hilafilcon A) without anaesthetic drops and then without the contact lens using one drop of 0.4% oxybuprocaine hydrochloride. Each contact lens used was identical as to back optic zone, back vertex power. Standard Goldmann procedure only was used for the fellow eye of each subject. Subjective sensation (discomfort) responses to both procedures were studied in a subgroup (66 eyes) using a scale of discomfort, from 1 (no sensation) to 5 (highest sensation). Epithelial staining after tonometry was evaluated for this subgroup. RESULTS: No significant differences were found for the IOP with and without contact lens (t<1; p=0.63) for the IOP range studied. There was a good correlation between the two procedures (r=0.81; p<0.05). Lowest sensation was found with tonometry on the anaesthetized cornea; this condition was significantly different from other conditions (p<0.005). No difference was found among the other conditions (contact lens insertion, tonometry on contact lens and application of topical anaesthetic). Corneal epithelial staining following the standard tonometry procedure was significantly higher than following the procedure with a contact lens (p<0.00005). CONCLUSIONS: Measurement of IOP by GAT over a daily disposable soft contact lens is accurate, compared to the standard procedure and within the IOP's normal range studied here. Also using a contact lens results in less trauma whilst discomfort is similar.  相似文献   
1000.
A new analytical model is used to describe the emitter of silicon solar cells in order to gain information on the surface recombination velocity S. The procedure takes advantage of the combined use of experimental measurements, done to determine the emitter saturation current Joe, and analytical modelling to relate Joe to S. Several experiments have been carried out on silicon solar cells having different emitter profiles subjected to various surface treatments. The influence of the surface on significant cell parameters has been analysed.  相似文献   
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