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91.
92.
Graphene: Modular Graphene‐Based 3D Covalent Networks: Functional Architectures for Energy Applications (Small 8/2016) 下载免费PDF全文
93.
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
94.
Luisa Barba Gianmichele Arrighetti Sonia Calligaris 《European Journal of Lipid Science and Technology》2013,115(3):322-329
Crystallization and melting properties of triacylglycerols in extra virgin olive oil were studied by using synchrotron X‐ray diffraction (XRD) and differential scanning calorimetry (DSC). The phase transitions were monitored by cooling and heating the samples at 2°C/min from 60 to ?60°C and vice versa. Upon cooling, a first DSC endothermic peak was recorded at ?9.6°C followed by one at ?33.5°C. These thermal events were associated to the formation of two different structures: a triple‐chain length (3L) having a c parameter of about 58.38 Å and a quadruple chain length structure (4L) with a c parameter of about 89.99 Å, respectively. Both structures evidenced a cell packing arrangement ascribable to a β′ form. During heating, part of the metastable β′ crystals rearranged into the more thermodynamically stable β form. Then, upon further heating, the sequential melting of the two crystal structures was observed. The melting was completed at 10.7°C. Beside this interpretation of XRD data, a model considering a cell with a c parameter of about 170 Å and a hexagonal crystal system was proposed. Even if more research is needed to validate this approach, it allowed all XRD events recorded during the experiments to be described. See commentary by Chiavaro [p. 267–269], http://dx.doi.org/10.1002/ejlt.201200415 相似文献
95.
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
96.
Martha Lomeli Luisa Maria Flores-Velez Imelda Esparza Roberto Torres Octavio Domínguez 《Journal of the American Ceramic Society》2009,92(7):1526-1533
The present work represents preliminary results concerning the effect of nanometric CaF2 particles on the sintering behavior of kaolin. The nanoparticles were synthesized using aqueous solutions of CaCl2 dissolved with an organic dispersant and HF. The morphology and particle size of the obtained nanoparticles were square-like, having a mean length of 25 nm. Kaolin was mixed with different amounts of nanometric CaF2 (from 0.625 to 5.0 wt%) and the mixtures were milled, pressed, and sintered. From sintering experiments, it was observed that additions of CaF2 nanoparticles in kaolin clay could shift the phase transition temperatures to lower values. Specifically, the densification temperature could be reduced by almost 150°C when 2.5 wt% of CaF2 was incorporated. Besides, adding 1.25% of nanometric CaF2 can achieve that compressive strength augments from 125 to 185 MPa in kaolin samples sintered at 1200°C, meaning an improvement of 40% in the properties of the final material. 相似文献
97.
Olga Luisa Tavano 《LWT》2008,41(7):1244-1251
The chickpea vicilin-like globulin was isolated and chromatographed on Sepharose CL-6B and Sephacryl S-300. The native globulin with a molecular weight of 140 kDa was resolved in Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in seven polypeptide bands in the range of 12.4-67 kDa. The solubility profile of the protein in water and NaCl solutions was typical of a legume globulin. The purified vicilin-like globulin, native and heated, was hydrolyzed by pepsin, trypsin and chymotrypsin. The hydrolysis patterns indicated that the native vicilin-like protein was only partially degraded by the enzymes in comparison with casein. Heating increased its susceptibility to hydrolysis relative to the native form, for all the enzymes. However, the results obtained by the pH-drop method revealed that the in vitro digestibility of the vicilin-like protein was not altered by heating, while 11S-like and total globulins suffered a small increase, indicating that the structural characteristics of storage globulins may be important factors limiting the protein digestion. 相似文献
98.
Nivia Maria Streit Luisa Helena Rychecki Hecktheuer Marta Weber do Canto Carlos Augusto Mallmann Letícia Streck Thaylise Vey Parodi Liana Pedrolo Canterle 《Food chemistry》2007,102(3):560-564
Erva-mate (Ilex paraguariensis St. Hil.) is a native species from temperate regions of South America, such as Brazil, Paraguay, and Argentina, that is consumed as a beverage known as mate. The objective of this research was to determine the content of caffeic acid, catechin, chlorogenic acid, caffeine, and gallic acid in mate to explain their influence in beverage taste and sensory differences between native and reforested plants, as well as between beverages from plants of different regions of Brazil (Santa Catarina and Rio Grande do Sul states). Compounds were determined by HPLC and results were related to a sensory evaluation performed by trained tasters. Tasters considered the beverage from reforested plants to be more bitter than the beverage from native plants. Beverages from reforested plants had significantly higher caffeic acid and lower catechin, chlorogenic acid, caffeine, and gallic acid content than native plants. Beverages from plants of Santa Catarina state had significantly higher catechin, caffeine, and gallic acid content than plants from Rio Grande do Sul state. 相似文献
99.
A. Clara Grosso Monya M. Costa Luisa Ganço Ana L. Pereira Generosa Teixeira José M.G. Lavado A. Cristina Figueiredo José G. Barroso Luis G. Pedro 《Food chemistry》2007,102(4):1083-1088
The essential oils, isolated by hydrodistillation and distillation-extraction, from the aerial parts of different populations of Pterospartum tridentatum collected during the flowering phase, at different locations in Portugal, were analysed by GC and GC–MS. All the P. tridentatum populations studied afforded a yellowish oil in a yield <0.05% (v/w). cis-Theaspirane (2–14%), trans-theaspirane (2–17%) and octen-3-ol (2–37%) were, in variable amounts, the dominant components of the oils. Cluster analysis of the essential oil compositions from the nine populations studied, confirmed a major chemical variability. 相似文献
100.
Heinis Christian; Huber Adrian; Demartis Salvatore; Bertschinger Julian; Melkko Samu; Lozzi Luisa; Neri Paolo; Neri Dario 《Protein engineering, design & selection : PEDS》2001,14(12):1043-1052
Phage display has been shown to facilitate greatly the selectionof polypeptides with desired properties by establishing a directlink between the polypeptide and the gene that encodes it. However,selection for catalytic activities displayed on phage remainsa challenge, since reaction products diffuse away from the enzymeand make it difficult to recover catalytically active phageenzymes.We have recently described a selection methodology in whichthe reaction substrate (and eventually the reaction product)is anchored on calmodulin-tagged phageenzymes by meansof a calmodulin binding peptide. Phage displaying a catalyticactivity are physically isolated by means of affinity reagentsspecific for the product of reaction. In this study, we investigatedthe efficiency of selection for catalysis by phage display,using a ligase (the Escherichia coli biotin ligase BirA) andan endopeptidase (the rat trypsin His57 相似文献