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991.
Fernando L. Taracena 《Quality Engineering》2006,18(1):33-37
Industry competitiveness requires the best possible quality-price combination; therefore, cost analysis is usually required at the design stages. Off-line quality control methods are conducted at the product and process design stages to improve manufacturing costs and quality of the product. An economic analysis is proposed in this article that can be carried out along with the known parameter design methods. The economic analysis in the experimental design does not add experimental costs and shows potential savings. The model minimizes the total expected quality cost, which includes the cost of using a set of factor levels and its expected quality loss. 相似文献
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Distributed video coding (DVC) is an emerging video coding technology that utilises the distributed source coding principles to build very low cost video encoders, yet with remarkable error resilience. In the most common DVC framework, the reconstruction function plays a vital role that has a direct impact on the output video quality. In this study, a novel algorithm is proposed for the reconstruction function, particularly focusing on a unidirectional DVC architecture. The proposed technique exploits the variations of the bit error rate of the Wyner-Ziv decoded bit stream and the assumed noise model in the side information stream. The simulation results show that the proposed algorithm yields a significant improvement of the objective and subjective video quality at no additional bit rate cost. 相似文献
996.
Silvia Gordillo Federico Balaguer Catalina Mostaccio Fernando Das Neves 《GeoInformatica》1999,3(1):7-32
In this paper we present an object-oriented approach for designing GIS applications; it combines well known software engineering practices with the use of design patterns as a conceptual tool to cope with recurrent problems appearing in the GIS domain. Our approach allows the designer to decouple the conceptual definition of application objects from their spatial representation. In this way, GIS applications can evolve smoothly, because maintenance is achieved by focusing on different concerns at different times. We show that our approach is also useful to support spatial features in conventional applications built with object-oriented technology. The structure of this paper is as follows: We first introduce design patterns, an efficient strategy to record design experience; then we discuss the most common design problems a developer of GIS applications must face. The core of our method is then presented by explaining how the use of decorators helps in extending objects to incorporate spatial attributes and behavior. Next, we analyze some recurrent design problems in the GIS domain and present some new patterns addressing those problems. Some further work is finally discussed. 相似文献
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Fernando Dourado Pedro Vasco Francisco M Gama Manuel A Coimbra Manuel Mota 《Journal of the science of food and agriculture》2000,80(13):1859-1865
The utilisation of enzymes for the extraction of vegetable oils from seeds has been a topic of growing interest in recent years. Knowledge of the cell wall polysaccharide composition is important to select the enzyme(s) necessary for the most effective degradation of the cell walls. The purpose of the present work is to characterise the seeds of Rosa Mosqueta (Rosa aff rubiginosa) by light microscopy (where several differential staining methods were applied to analyse the seed structure) and by the isolation of cell wall polysaccharide extracts. The mature seed of Rosa Mosqueta has a very thick and structurally complex seed coat comprising heavily lignified tissue. The embryo has two cell layers of remaining endosperm tissue (indicating that this is an exalbuminous seed), two voluminous cotyledons that contain the oil, and bundles of provascular tissues distributed perpendicularly to the transverse axis of the embryo. The major non‐cellulosic polysaccharides from the non‐lignified tissues are glucuronoxylans and pectic polysaccharides; glucans are also present in small amounts. The major non‐cellulosic polysaccharides from the lignified tissues are glucuronoxylans. Concerning the use of enzymes for oil extraction, microscopy and cell wall polysaccharide analysis showed that the use of pectic enzymes followed by a xylanase or a cellulase should be explored. © 2000 Society of Chemical Industry 相似文献
999.
Tamara Rosell-García Sergio Rivas-Muoz Alain Colige Fernando Rodriguez-Pascual 《International journal of molecular sciences》2022,23(6)
Members of the lysyl oxidase (LOX) family catalyze the oxidative deamination of lysine and hydroxylysine residues in collagen and elastin in the initiation step of the formation of covalent cross-links, an essential process for connective tissue maturation. Proteolysis has emerged as an important level of regulation of LOX enzymes with the cleavage of the LOX isoform by metalloproteinases of the BMP1 (bone morphogenetic protein 1) and ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) families as a model example. Lysyl oxidase-like 1 (LOXL1), an isoform associated with pelvic organ prolapse and pseudoexfoliation (PEX) glaucoma, has also been reported to be proteolytically processed by these proteases. However, precise molecular information on these proteolytic events is not available. In this study, using genetic cellular models, along with proteomic analyses, we describe that LOXL1 is processed by BMP1 and ADAMTS14 and identify the processing sites in the LOXL1 protein sequence. Our data show that BMP1 cleaves LOXL1 in a unique location within the pro-peptide region, whereas ADAMTS14 processes LOXL1 in at least three different sites located within the pro-peptide and in the first residues of the catalytic domain. Taken together, these results suggest a complex regulation of LOXL1 function by BMP1- and ADAMTS14-mediated proteolysis where LOXL1 enzymes retaining variable fragments of N-terminal region may display different capabilities. 相似文献
1000.
Marco Artini Esther Imperlini Francesco Buonocore Michela Relucenti Fernando Porcelli Orlando Donfrancesco Vanessa Tuccio Guarna Assanti Ersilia Vita Fiscarelli Rosanna Papa Laura Selan 《International journal of molecular sciences》2022,23(21)
Pseudomonas aeruginosa is an opportunistic pathogen causing several chronic infections resistant to currently available antibiotics. Its pathogenicity is related to the production of different virulence factors such as biofilm and protease secretion. Pseudomonas communities can persist in biofilms that protect bacterial cells from antibiotics. Hence, there is a need for innovative approaches that are able to counteract these virulence factors, which play a pivotal role, especially in chronic infections. In this context, antimicrobial peptides are emerging drugs showing a broad spectrum of antibacterial activity. Here, we tested the anti-virulence activity of a chionodracine-derived peptide (KHS-Cnd) on five P. aeruginosa clinical isolates from cystic fibrosis patients. We demonstrated that KHS-Cnd impaired biofilm development and caused biofilm disaggregation without affecting bacterial viability in nearly all of the tested strains. Ultrastructural morphological analysis showed that the effect of KHS-Cnd on biofilm could be related to a different compactness of the matrix. KHS-Cnd was also able to reduce adhesion to pulmonary cell lines and to impair the invasion of host cells by P. aeruginosa. A cytotoxic effect of KHS-Cnd was observed only at the highest tested concentration. This study highlights the potential of KHS-Cnd as an anti-biofilm and anti-virulence molecule against P. aeruginosa clinical strains. 相似文献