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101.
102.
Integration of collaboration and interaction analysis mechanisms in a concern-based architecture for groupware systems 总被引:1,自引:0,他引:1
Collaboration and interaction analysis allows for the characterization and study of the collaborative work performed by the users of a groupware system. The results of the analyzed processes allow problems in users’ collaborative work and shortcomings in the functionalities of the groupware system to be identified. Therefore, automating collaboration and interaction analysis enables users’ work to be assessed and groupware system support and behavior to be improved. This article proposes a concern-based architecture to be used by groupware developers as a guide to the integration of analysis subsystems into groupware systems. This architecture was followed to design the COLLECE groupware system, which supports collaborative programming practices and integrates an analysis subsystem that assesses different aspects of the work carried out by the programmers and adapts the functionality of the system under specific conditions. 相似文献
103.
This paper describes an experimental setup for the investigation of two-phase heat transfer inside microchannels and reports local heat transfer coefficients measured during flow boiling of HFC-245fa in a 0.96-mm-diameter single circular channel. The test runs have been performed during vaporization at around 1.85 bar, corresponding to 31°C saturation temperature. As a peculiar characteristic of the present technique, the heat transfer coefficient is not measured by imposing the heat flux; instead, the boiling process is governed by controlling the inlet temperature of the heating secondary fluid. In the data, mass velocity ranges between 200 and 400 kg m?2 s?1, with heat flux varying from 5 to 85 kW m?2 and vapor quality from 0.05 up to 0.8. Since these data are not measured at uniform heat flux conditions, a proper analysis is performed to enlighten the influence of the different parameters and to compare the present data to those obtained when the heat flux is imposed. Besides, the test runs have been carried out in a double mode: by increasing the water-to-refrigerant temperature difference and by decreasing it. Finally, the experimental data are compared to models available in the literature for predicting the heat transfer coefficients inside microchannels. 相似文献
104.
Luisa M. S. Gonçalves Cidália C. Fonte Eduardo N. B. S. Júlio Mario Caetano 《International journal of remote sensing》2013,34(9):2851-2867
The production of thematic maps from remotely sensed images requires the application of classification methods. A great variety of classifiers are available, producing frequently considerably different results. Therefore, the automatic extraction of thematic information requires the choice of the most appropriate classifier for each application. One of the main objectives of the research described in this article is to evaluate the performance of supervised classifiers using the information provided by the application of uncertainty measures to the testing sets, instead of statistical accuracy indices. The second main objective is to show that the information provided by the uncertainty measures for the training set may be used to assess and redefine the sample sites included in this set, in order to improve the classification results. To achieve the proposed objectives, two supervised classifiers, one probabilistic and another fuzzy, were applied to a very high spatial resolution (VHSR) image. The results show that similar conclusions on the classifiers’ performance are obtained with the uncertainty measures and the traditional accuracy indices obtained from error matrices. It is also shown that the redefinition of the training set based on the information provided by the uncertainty measures may generate more accurate outputs. 相似文献
105.
Effect of selected mould strains on the sensory properties of dry fermented sausages 总被引:2,自引:0,他引:2
M. Luisa Garcia Carmen Casas Victor M. Toledo M. D. Selgas 《European Food Research and Technology》2001,212(3):287-291
The effect of one Mucor and two Penicillium strains (Penicillium-3 and Penicillium-6) on the development of the sensory properties of dry fermented sausages has been studied. These strains were previously isolated from Spanish fermented sausages and selected for their proteolytic and lipolytic activity. Several experimental batches were prepared: one of them was non-inoculated and considered as control batch, three were inoculated with the selected strains, and the last one was inoculated with a commercial starter culture of P. nalgiovense. The pleasantness of the sensory attributes of the different batches were determined using an unstructured line scale of 10 cm. A triangular test was also carried out. Apart from their external appearance, batches inoculated with Mucor and Penicillium-3 had the highest scores for all the sensory attributes studied. The batch inoculated with P. nalgiovense had the lowest scores and similar to the control batch but its external appearance was considered to be the most pleasant. The batch inoculated with Penicillium-6 presented intermediate characteristics. A relation between these results and the enzymic activity of the moulds was established. The three strains selected for this study are proposed to be incorporated in a commercial starter culture because they improve the sensory properties of these meat products. 相似文献
106.
Murtas C Bruschi M Carnevali ML Petretto A Corradini E Prunotto M Candiano G degl'Innocenti ML Ghiggeri GM Allegri L 《Proteomics. Clinical applications》2011,5(1-2):90-97
Renal auto-immune diseases represent a major source of morbidity in humans. For many years the knowledge on mechanisms of auto-immunity involving the kidney has been uniquely based on animal models. However, these findings often could not be readily translated to humans owing to notably difference in antigen expression by human podocytes. One example is Heymann nephritis (HN), the experimental model of human membranous glomerulonephritis (MGN), which is obtained in rats by injecting antibodies against megalin, a protein that is not present in human glomeruli. Human studies could not be done in the past since sequencing required too much material exceeding what obtainable from tissue biopsies in vivo. Research is now on the way to identify auto-antigens and isolate specific auto-antibodies in humans. New technology developments based on tissue microdissection and proteomical analysis have facilitated the recent discoveries, allowing direct analysis of human tissue in vivo. Major advances on the pathogenesis of MGN, the prototype for the formation and glomerular deposition of auto-antibodies, are now in progress. Two independent groups have, in fact, demonstrated the existence of specific IgG(4) against phospholipase A2 receptor, aldose reductase and Mn-superoxide dismutase in glomerular eluates and in plasma of a prominent part of patients with MGN, suggesting a major role of these proteins as auto-antigens in human MGN. This review will focalize these aspects outlining the contribution of proteomics in most recent developments. 相似文献
107.
Rodríguez E Simoes RV Roig A Molins E Nedelko N Slawska-Waniewska A Aime S Arús C Cabañas ME Sanfeliu C Cerdán S García-Martín ML 《Magma (New York, N.Y.)》2007,20(1):27-37
A new iron-based T 1 contrast agent consisting of a complex of iron ions coordinated to phosphate and amine ligands (Fe(phos) in short) has been characterized by spectroscopic and magnetic measurements. NMR relaxation studies showed r 1 values to be dependent on the phosphate salt concentration, K2HPO4, present in the medium. r 1 reaches a maximum value of 2.5 mM?1 s?1 for measurements carried out at 7 T and 298 K. 31P MRS, Mössbauer spectroscopy and magnetic measurements of Fe(phos) solutions suggest paramagnetic Fe3+ ions present in the studied iron–phosphate complex. In vitro and in vivo toxicity experiments with C6 cells and CD1 mice, respectively, demonstrated lack of toxicity for Fe(phos) at the highest dose tested in the MRI experiments (12 mM iron for C6 cells and 0.32 mmol iron/kg for mice). Finally, T 1 weighted images of brain tumours in mice have shown positive contrast enhancement of Fe(phos) for tumour afflicted regions in the brain. 相似文献
108.
Continuity as the mathematical tool in the creation of architectural forms is known as morphocontinuity. In the present work, we explain how morphocontinuity appears on the work of Eero Saarinen and discuss its correspondence with its environmental (physical, social and cultural) contexts. 相似文献
109.
Luisa María Gil-Martín Enrique Hernández-Montes Mark Aschheim 《Structural and Multidisciplinary Optimization》2010,41(6):979-987
The ultimate strength design of reinforced concrete members under flexure and axial loads is well known, with solutions dating back to the 1950s. There is little motivation for engineers to change solution approaches in the absence of a clear benefit, particularly given that current solution approaches are well-known and do not raise controversy. Recently, a different solution approach has been presented in the form of Reinforcement Sizing Diagrams and Optimal Domains, but applications to rectangular sections were limited and thus the approach has been mainly of academic or theoretical interest. This paper presents an application to circular sections, which allow the advantages to be realized in the commonly encountered situation of retaining walls supported by circular section piers. Using the approach presented herein, longitudinal reinforcement can be reduced up to 50% compared with traditional designs, allowing significant financial savings while also reducing the greenhouse gas emissions associated with the reinforcement component of reinforced concrete construction. 相似文献
110.
Nunzia DOnofrio Elisa Martino Luigi Mele Antonino Colloca Martina Maione Domenico Cautela Domenico Castaldo Maria Luisa Balestrieri 《International journal of molecular sciences》2021,22(15)
Understanding the mechanisms of colorectal cancer progression is crucial in the setting of strategies for its prevention. δ-Valerobetaine (δVB) is an emerging dietary metabolite showing cytotoxic activity in colon cancer cells via autophagy and apoptosis. Here, we aimed to deepen current knowledge on the mechanism of δVB-induced colon cancer cell death by investigating the apoptotic cascade in colorectal adenocarcinoma SW480 and SW620 cells and evaluating the molecular players of mitochondrial dysfunction. Results indicated that δVB reduced cell viability in a time-dependent manner, reaching IC50 after 72 h of incubation with δVB 1.5 mM, and caused a G2/M cell cycle arrest with upregulation of cyclin A and cyclin B protein levels. The increased apoptotic cell rate occurred via caspase-3 activation with a concomitant loss in mitochondrial membrane potential and SIRT3 downregulation. Functional studies indicated that δVB activated mitochondrial apoptosis through PINK1/Parkin pathways, as upregulation of PINK1, Parkin, and LC3B protein levels was observed (p < 0.0001). Together, these findings support a critical role of PINK1/Parkin-mediated mitophagy in mitochondrial dysfunction and apoptosis induced by δVB in SW480 and SW620 colon cancer cells. 相似文献