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941.
This work fully demonstrated the formation of amino acids complexes with β-cyclodextrin (β-CD) by the method of nuclear magnetic resonance with the rotating frame Overhauser effect spectroscopy (ROESY) and diffusion ordered spectroscopy (DOSY) techniques. The tested amino acids display the following decreasing order of affinity for β-CD: tryptophane > tyrosine > phenylalanine > proline > histidine > isoleucine. The influence of complexation on taste perception was determined with a trained panel to qualify taste alterations of single amino acids and quantify the debittering of soy protein hydrolysate by β-CD complexation. The results showed that β-CD complexation is effective for modifying single amino acids taste perception and debittering soy protein hydrolysate. Bitterness sensation of the latter is reduced by 90% when 5% β-CD was added, thus β-CD is recommended as a prospective additive for masking bitter taste of new functional food products.  相似文献   
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944.
We highlight the importance of exome sequencing in solving a clinical case of a child who died at 14 months after a series of respiratory crises. He was the half-brother of a girl diagnosed at 7 years with the early-onset seizure variant of Rett syndrome due to CDKL5 mutation. We performed a test for CDKL5 in the boy, which came back negative. Driven by the mother’s compelling need for a diagnosis, we moved forward performing whole exome sequencing analysis. Surprisingly, two missense mutations in compound heterozygosity were identified in the RAPSN gene encoding a receptor-associated protein with a key role in clustering and anchoring nicotinic acetylcholine receptors at synaptic sites. This gene is responsible for a congenital form of myasthenic syndrome, a disease potentially treatable with cholinesterase inhibitors. Therefore, an earlier diagnosis in this boy would have led to a better clinical management and prognosis. Our study supports the key role of exome sequencing in achieving a definite diagnosis in severe perinatal diseases, an essential step especially when a specific therapy is available.  相似文献   
945.
Massively parallel processor array (MPPA) architectures are becoming widely available computing platforms. Because of formal similarities, they are good candidates for implementing cellular automata (CA). An essential difference still remains regarding the freedom in communications. In MPPA there is a fixed on-chip network interconnection topology but every CA has its own definition of neighbourhood. While a cell in a CA can be considered as directly connected to its neighbours, these connections correspond to paths in the network of the MPPA. The communications need to be routed and scheduled to reach their proper destination. In previous work we introduced a formal data-flow process network model named KRG (for K-periodically Routed Graph). Its main feature is to allow regular switching directives. In the present paper we will use it to represent the proper local sequences of routing directives that will efficiently propagate values from cells to cells so as to implement the required CA neighbourhood. We present the neighbourhood broadcasting algorithm that computes these routing directives. One should note here that the problem is made more complex as data traffic between distinct source and target cells must be merged, while multicast may save a tremendous amount of communications when values are required in multiple locations. We demonstrate the expressive power of our formalism on the case of a 2D CA where the neighbourhood consists of all cells at Moore distance at most n. Further potential applications of our framework are hinted.  相似文献   
946.
Reasoning aboutfacts and reasoning aboutarguments regarding facts are distinct activities, and automated reasoning systems should be able to treat them accordingly. In this work, we discuss one precise sense in which this distinction can be envisaged and suggest the use of Annotated Logics to characterise it.  相似文献   
947.
Increasing the conductivity of polycrystalline zinc oxide films without impacting the transparency is a key aspect in the race to find affordable and high quality material as replacement of indium‐containing oxides. Usually, ZnO film conductivity is provided by a high doping and electron concentration, detrimental to transparency, because of free carrier absorption. Here we show that hydrogen post‐deposition plasma treatment applied to ZnO films prepared by metalorganic low‐pressure chemical vapor deposition allows a relaxation of the constraints of the conductivity/transparency trade‐off. Upon treatment, an increase in electron concentration and Hall mobility is observed. The mobility reaches high values of 58 and 46 cm2V?1s?1 for 2‐μm‐ and 350‐nm‐thick films, respectively, without altering the visible range transparency. From a combination of opto‐electronic measurements, hydrogen is found, in particular, to reduce electron trap density at grain boundaries. After treatment, the values for intragrain or optical mobility are found similar to Hall mobility, and therefore, electron conduction is found to be no longer limited by the phenomenon of grain boundary scattering. This allows to achieve mobilities close to 60 cm2V?1s?1, even in ultra‐transparent films with carrier concentration as low as 1019 cm?3.  相似文献   
948.
The behavior of alumina nano-particles taken from a commercial powder is investigated during in situ compression experiments in a transmission electron microscope (TEM). Small particles of 40 nm in diameter can undergo severe plastic deformation without failure, whereas brittle fracture is observed for 120 nm sized nano-particles. This is evidence of a critical size under which alumina, at least in the form of nano-particles, cannot be considered as brittle materials even at room temperature and a direct observation of the grinding limit generally observed during ball milling.  相似文献   
949.
Organisms make the best of their mother’s oviposition choices and utilize specific feeding options that meet energetic requirements and cope with environmental constraints. This is particularly true for leaf-miner insects that develop enclosed in the two epidermis layers of a single leaf for their entire larval life. Cytokinins (CKs) play a central role in plant physiology – including regulation of senescence and nutrient translocation – and, as such, can be the specific target of plant exploiters that manipulate plant primary metabolism. ‘Green-islands’ are striking examples of a CK-induced phenotype where green areas are induced by plant pathogens/insects in otherwise yellow senescent leaves. Here, we document how the leaf-miner caterpillar Phyllonorycter blancardella, working through an endosymbiotic bacteria, modifies phytohormonal profiles, not only on senescing (photosynthetically inactive) but also on normal (photosynthetically active) leaf tissues of its host plant (Malus domestica). This leaf physiological manipulation allows the insect to maintain sugar-rich green tissues and to create an enhanced nutritional microenvironment in an otherwise degenerating context. It also allows them to maintain a nutritional homeostasis even under distinct leaf environments. Our study also highlights that only larvae harboring bacterial symbionts contain significant amounts of CKs that are most likely not plant-derived. This suggests that insects are able to provide CKs to the plant through their symbiotic association, thus extending further the role of insect bacterial symbionts in plant-insect interactions.  相似文献   
950.
Silver containing coating can represent a solution to the recurring problem of biofilm formation on implant surfaces. In this study, the development of a titanium oxide coating containing silver particles is reported. The coating was obtained on medical grade Ti-6Al-4V alloy by anodic spark deposition in an aqueous electrolyte. Surface characterization revealed a high specific surface area with a succession of flat plateaus and depressions. Silver was present all over the coating surface as small particles of sizes below 200 nm. When immersed in a liquid medium, the coating released silver ions at a constant rate over more than 15 days. The coating was able to show a complete killing of gentamicin-resistant Staphylococcus epidermidis within the first 12 h after inoculation.  相似文献   
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