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191.
Cardiovascular diseases causing high morbidity and mortality represent a major socioeconomic burden. The primary cause of impaired heart function is often the loss of cardiomyocytes. Thus, novel therapies aim at restoring the lost myocardial tissue. One promising approach is cardiac tissue engineering. Previously, it is shown that Antheraea mylitta silk protein fibroin is a suitable material for cardiac tissue engineering, however, its quality is difficult to control. To overcome this limitation, the interaction of primary rat heart cells with engineered Araneus diadematus fibroin 4 (κ16) (eADF4(κ16)) is investigated here, which is engineered based on the sequence of ADF4 by replacing the glutamic acid residue in the repetitive unit of its core domain with lysine. The data demonstrate that cardiomyocytes, fibroblasts, endothelial cells, and smooth muscle cells attach well to eADF4(κ16) films on glass coverslips which provide an engineered surface with a polycationic character. Moreover, eADF4(κ16) films have, in contrast to fibronectin films, no hypertrophic effect but allow the induction of cardiomyocyte hypertrophy. Finally, cardiomyocytes grown on eADF4(κ16) films respond to pro‐proliferative factors and exhibit proper cell‐to‐cell communication and electric coupling. Collectively, these data demonstrate that designed recombinant eADF4(κ16)‐based materials are promising materials for cardiac tissue engineering.  相似文献   
192.
Spin‐polarized charge transfer at the interface between a ferromagnetic (FM) metal and a molecule can lead to ferromagnetic coupling and to a high spin polarization at room temperature. The magnetic properties of these interfaces can not only alter those of the ferromagnet but can also stabilize molecular spin chains with interesting opportunities toward quantum computing. With the aim to enhance an organic spintronic device's functionality, external control over this spin polarization may thus be achieved by altering the ferromagnet/molecule interface's magnetic properties. To do so, the magnetoelectric properties of an underlying ferroelectric/ferromagnetic interface are utilized. Switching the ferroelectric polarization state of a PbZr0.2Ti0.8O3 (PZT) bottom layer within a PZT/Co/FePc‐based (Pc ‐ phthalocyanine) device alters the X‐ray magnetic circular dichroism of the Fe site within the phthalocyanine molecular top layer. Thus, how to electrically alter the magnetic properties of an interface with high spin polarization at room temperature is demonstrated. This expands electrical control over spin‐polarized FM/molecule interfaces, which is first demonstrated using ferroelectric molecules, to all molecular classes.  相似文献   
193.
In this paper, we present the final version of a publicly available treebank of Finnish, the Turku Dependency Treebank. The treebank contains 204,399 tokens (15,126 sentences) from 10 different text sources and has been manually annotated in a Finnish-specific version of the well-known Stanford Dependency scheme. The morphological analyses of the treebank have been assigned using a novel machine learning method to disambiguate readings given by an existing tool. As the second main contribution, we present the first open source Finnish dependency parser, trained on the newly introduced treebank. The parser achieves a labeled attachment score of 81 %. The treebank data as well as the parsing pipeline are available under an open license at http://bionlp.utu.fi/.  相似文献   
194.
In building and tuning good settling models for secondary clarifiers of wastewater treatment plants, there is a need for measured continuous solids concentration profiles during batch settling. Conventional measuring techniques have difficulties in recording this kind of data, either because they are invasive, or because of the low solids concentration and/or solids density of activated sludge. This paper investigates a novel non-invasive measurement technique borrowed from nuclear medicine, using a solids radiotracer and gamma cameras, to obtain solids concentration profiles during the batch settling of activated sludge, in a pilot-scale column with a height of 1m. The technique does not disturb the settling process, does not alter the settling characteristics, gives profiles every minute and every few millimeters, and is capable of measuring in a range of 0-25 g/l with high accuracy. Dynamic solids concentration profile measurements were performed for sludges of different wastewater treatment plants, and at different initial concentrations. The results show a quantitative representation of the settling process, and reveal hindered and compression settling.  相似文献   
195.
Concern about heavy metal accumulation in agricultural soils under long-term application of phosphate fertilizers and organic wastes makes investigation of heavy metals in agricultural soils imperative. This study examines the total, available and chemical forms of lead (Pb) in a savanna soil after 50 years of continuous cultivation and application of NPK fertilizers and farmyard manure (FYM). Total Pb concentration ranged from 28 to 42 mg kg(-1) over 2-3 times more than the average Pb concentration of non-polluted soils worldwide. Available Pb was, however, less than 2 mg kg(-1) indicating that Pb in the soils was largely insoluble. There were no detectable concentrations of water soluble and organically-bound Pb fractions. On average, residual Pb accounted for over 80% of total Pb. Compared to the natural site, cultivation and fertilization with NPK and FYM increased total Pb concentration by 19 and 17%, respectively, or, on mass basis, by 10 and 35 kg ha(-1), respectively, after 50 years. Soil Pb showed strong linear relations with sand fraction and inorganic phosphorus in the soils. Thermodynamic equilibrium relations provided some indirect evidence that the control on soluble Pb appeared to be chloropyromorphite [Pb5(PO4)3Cl], an insoluble lead phosphate mineral.  相似文献   
196.
Flavour changes of six Belgian pale lager beers were studied in order to estimate the importance of different parameters and reactions in relation to the ageing process. An attempt was made to link analytical data with sensory evaluation using multivariate statistical analysis. Partial least squares regression techniques (PLSR) were employed on the analytical and sensory data. As apparent from the PLSR model, significant indicators of lager beer ageing are aldehyde markers (especially total aldehydes, furfural, hexanal, 2‐methylpropanal, 2‐methylbutanal, and 3‐methylbutanal), cold and permanent haze, and beer colour. Conversely, compounds or parameters that load negatively in the PLSR model for beer ageing are trans‐isohumulones, cis‐isohumulones, total bitterness, the T/C‐ratio, polyphenolic markers (especially proanthocyanidins), the flavanoid content, and, to a lesser extent, the TB‐index and reducing power (TRAP). The integrated analytical‐sensorial methodology is proposed as a useful tool for evaluation of the flavour instability of pale lager beers.  相似文献   
197.
Distributed Video Coding (DVC) is a video coding paradigm in which the computational complexity is shifted from the encoder to the decoder. DVC is based on information theoretic results suggesting that, under ideal conditions, the same rate-distortion performance can be achieved as for traditional video codecs. In practice however, there is still a significant performance gap between the two coding architectures. One of the main reasons for this gap is the lack of multiple coding modes in current DVC solutions. In this paper, we propose a block-based distributed video codec that supports three coding modes: Wyner–Ziv, skip, and intra. The mode decision process is entirely decoder-driven. Skip blocks are selected based on the estimated accuracy of the side information. The choice between intra and Wyner–Ziv coding modes is made on a rate-distortion basis, by selecting the coding mode with the lowest rate while assuring equal distortion for both modes. Experimental results illustrate that the proposed block-based architecture has some advantages over classical bitplane-based approaches. Introducing skip and intra coded blocks yields average bitrate gains of up to 33.7% over our basic configuration supporting Wyner–Ziv mode only, and up to 29.7% over the reference bitplane-based DISCOVER codec.  相似文献   
198.
A novel platform of side-chain functionalized crosslinked polyurethane (PU) films and foams has been used to afford new classes of PU materials. Indeed, alkyne pendant groups located along the polyurethane backbone have been modified via the copper catalyzed Huisgen 1,3-dipolar cycloaddition with various azide components. These cycloaddition reactions were carried out in water or in a mixture of water/acetone under mild conditions (room temperature to 50 °C) in the presence of low amounts of copper catalyst. The resulting functionalized films and foams were all characterized by FT-IR, contact angle measurements and confocal fluorescence microscopy. All these techniques successfully proved that the click chemistry process is valuable in functionalizing PU films and foams in an easy way. The post-functionalization of these alkyne-functionalized PUs afforded the creation of new classes of PU materials with easily adaptable physical properties by choosing the appropriate azide component.  相似文献   
199.
Multimedia Tools and Applications - Multimodal data is being used more widely for human action recognition nowadays due to the progress of machine learning methods and the development of new types...  相似文献   
200.
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