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991.
Previous research suggests that landscape preferences vary systematically amongst people. While various sources of heterogeneity have been considered in landscape preference literature, the role of emotions on willingness to pay for landscape features has never been examined. This article presents results of a choice experiment carried out for eliciting tourists’ for Alpine landscapes. The emotional state of respondents was used to model heterogeneity in a latent class approach. The study area is a valley in the Italian Alps, characterised by a strong importance of the primary sector and a low number of tourists. Landscape management could attract new visitors, providing additional income for the local inhabitants. Results indicate that respondents prefer a variegated and multi-faceted landscape, with a mix of tree species, several agricultural crops and open areas with grazing animals and that incidental emotions play a role in the construction of landscape preferences and influence willingness to pay. 相似文献
992.
Alessandro Balducci 《Planning Theory & Practice》2013,14(2):249-255
Planning has increasingly been portrayed as a “service” provided to “customers”. This paper challenges such a view, and highlights some important dimensions of the relationship between planners and users of the planning service that have been overlooked in previous studies. It draws on sociological research into consumption to interrogate the various logics that underlie the concept of “customer-focused” planning services, and shows that they are typically based on an oversimplification of the relationships involved in both producing and consuming planning services. In particular, analyses of these reforms tend to underplay the demands that are made of consumers of planning services. The new analytic framework that is presented is illustrated with a case study that investigates the experience of small businesses when applying for planning permission. 相似文献
993.
Alessandro Vittorio Bergami Camillo Nuti 《土木工程与建筑:英文版》2014,(7):815-823
The research presented in this paper deals with the seismic protection of existing frame structures by means of passive energy dissipation. An iterative displacement-based procedure, based on capacity spectrum, to design dissipative bracings for seismic retrofitting of the frame structures is described, and some applications are discussed. The procedure can be used with any typology of dissipative device and for different performance targets. In this work, the procedure has been applied, with both traditional pushover (load profile proportional to first mode) and multimodal pushover, to an existing RC (reinforced concrete) frame building. In the application, the buckling restrained braces have been used in order to prevent damages to both the structure and non structural elements. The use of multimodal pushover proves to be more effective than pushover based on single mode in case of medium rise RC frame building (higher than 30 m) but, once this building is retrofitted, and therefore regularized, with a bracing system, the difference between using monomodal or multimodal pushover becomes insignificant. 相似文献
994.
Giacomo Squeo Antonia Tamborrino Antonella Pasqualone Alessandro Leone Vito Michele Paradiso Carmine Summo Francesco Caponio 《Food and Bioprocess Technology》2017,10(3):592-602
New generation decanters allow operators to make real-time adjustments during the virgin olive oil extraction process in order to gain the best performance possible. However, the opportunity to act in line requires a deep understanding of the consequences of changing machine parameters. To this purpose, an experiment was carried out at industrial scale. The decanter feed rate (Fr), ranging from 4075 to 5820 kg h?1, the bowl/screw conveyor differential speed (?n), set at 18 and 22, and two ripening degrees of the olives were considered as process variables. Two combinations Fr-?n, namely 4620 kg h?1 at ?n-18 and 5210 kg h?1 at ?n-22, were found to similarly maximize the process efficiency, regardless the raw material features. After pointing out the best working settings, the corresponding virgin olive oils were compared. The analysis of variance showed that peroxide value, K 232, K 270, phenols, chlorophylls, β-tocopherol, fruity and bitter notes, and C6 volatile compounds were significantly affected by the machine parameters. An inverse proportionality was observed between the combination Fr-?n and the phenolic compounds. On the whole, the sampling factor exerted a larger influence on the product quality than the decanter set-up. 相似文献
995.
Tâmmila Venzke Klug Júnia Novello Daniela Comparsi Laranja Tanira A. S. Aguirre Alessandro de Oliveira Rios Eduardo Cesar Tondo Rinaldo Pires dos Santos Renar João Bender 《Food and Bioprocess Technology》2017,10(2):275-283
Lettuce is often involved in foodborne outbreaks caused by pathogenic Escherichia coli. Current control strategies have often proved ineffective to ensure safe food production. For that reason, the present study compared the efficacy of tannin extracts and chlorine treatments on the reduction of E. coli ATCC 25922 adhered to lettuce leaves. E. coli was inoculated artificially on leaf surfaces of fresh crisp lettuce. Effectiveness of water, chlorine (200 mg/L), and three commercial available tannin extracts from Acacia mearnsii De Wild. (tannin AQ (2 %, w/v), tannin SG (1 %, v/v) and tannin SM (1 %, v/v)) treatments was evaluated using the viable plate count method and scanning electron microscopy (SEM). SEM results revealed that bacterial cells are attached as individual cells and in clusters to the leaf surface after 2 h of incubation. Biofilm formation was observed after 24 h of incubation. The tannin SM treatment was able to reduce counts in approximately 2 log CFU/cm2 on leaf segments. However, treatment was less effective in the reduction of E. coli counts after 24 h of incubation when compared to 2 h incubation of the same extract. The results suggest that the tannin SM extract diminishes E. coli counts adhered to and under biofilm formation on lettuce leaves and its effect is similar to the use of chlorine solutions. 相似文献
996.
Giovana de Arruda Moura Pietrowski Mayara Grochoski Gabriela Felkl Sartori Tatiane Aparecida Gomes Gilvan Wosiacki Alessandro Nogueira 《Yeast (Chichester, England)》2015,32(8):559-565
Hanseniaspora yeasts are known to produce volatile compounds that give fruity aromas in wine and fermented fruit. This study aimed to verify the feasibility of the Hanseniaspora uvarum strain that had been isolated and identified during a previous study and preserved by lyophilization and freezing at ?80 °C (cryopreservation). This strain was assessed in relation to its macroscopic and microscopic morphology and for its ability to ferment apple must. After having been subjected to lyophilization and cryopreservation, viability was assessed in relation to these characteristics during 12 months of storage. The strain showed stable colonial features and its microscopic appearance was unchanged during all recoveries. The plate count results showed consistency in both processes. Regarding the fermentative capacity, the kinetic results showed 100% viability for the strain subjected to lyophilization, as well as for those preserved at ?80 °C. These results demonstrate that the preservation methods used are compatible with the maintenance of the relevant characteristics of the strain for the period of evaluation of this study (12 months). Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
997.
Alessandra Danza Marcella MastromatteoFlora Cozzolino Lucia LecceVincenzo Lampignano Janine LaverseMatteo Alessandro Del Nobile 《LWT》2014
The effect of the addition of yellow pepper flour on bread physico-chemical and sensorial properties was addressed in this study. In particular, vegetable flour concentration was set at 25%; in order to optimize the bread sensorial properties, yellow pepper flour was separately hydrated at three different water content levels. Texture analysis were carried out on both dough and bread samples to evaluate their firmness. Furthermore, tomographic analysis was performed on the same samples in order to provide a more detailed view of their texture. Estimation of the glycemic response, determination of the carotenoids content and sensory analysis of the fortified bread were also determined. Results highlighted that the highest glycemic index was achieved in bread sample having the highest water content and that showed the worst results in terms of texture. Among the studied samples, bread with medium hydration level showed good structural characteristic, double anti-oxidant content compared to the control bread (CTRL S) and the highest sensorial quality. 相似文献
998.
Michela Zanetti Valerio Causin Roberta Saini Alessandro Cardin Raffaele Cavalli 《Holz als Roh- und Werkstoff》2014,72(3):385-392
Tannins have been largely studied as wood additives and wood adhesives. In a perspective of a desirably increased utilization of natural raw material in the wood timber industries, this study provides further and specific information on the use of condensed tannins to improve the heat resistance of urea–formaldehyde (UF) resins. The results obtained by thermomechanical and thermogravimetric analyses show that high percentage (33 and 50 %) of quebracho tannin in UF-tannin blend dramatically improves the overall UF thermal resistance, but 50 % of tannin decreases the maximum value of modulus of elasticity (MOE) of the bonded joint. The best balance between mechanical performance and decreased degradation at high temperature is obtained with 33 % of quebracho tannin. The MOE value of UF + 33 % of quebracho tannin at 260 °C is seven times greater than MOE of UF control. Thermograms show that quebracho tannin has a beneficial effect on increasing the resistance of glue-mix to degradation induced by temperature. When the content of tannin in the glue-mix is increased up to 50 %, the resin degrades completely at about 670 °C, i.e. more than 50 °C higher than neat UF resin. This improvement is related mainly to the resorcinol-type ring structure of tannin and the alkaline pH of UF + quebracho tannin glue mix that confer a higher resistance against joint degradation to UF even at elevated temperatures. 相似文献
999.
Alessandro Musetti Katia Paderni Paola Fabbri Andrea Pulvirenti Marwa Al‐Moghazy Patrizia Fava 《Journal of food science》2014,79(4):E577-E582
This work aimed at developing a thin and water‐resistant food‐grade poly(vinyl alcohol) (PVOH)‐based matrix able to swell when in contact with high moisture content food products without rupturing to release antimicrobial agents onto the food surface. This film was prepared by blending PVOH and 7.20% (wt/wt of PVOH) of poly(ethylene glycol) (PEG) with citric acid as crosslinking agent. The film‐forming solution was then casted onto a flat surface and the obtained film was 60 μm in thickness and showed a good transparency (close to T = 100%) in the visible region (400 to 700 nm). After immersion in water for 72 h at room temperature, the crosslinked matrix loses only 19.2% of its original weight (the percentage includes the amount of unreacted crosslinking agent, antimicrobial in itself). Water content, degree of swelling, and crosslinking density of the film prove that the presence of PEG diminishes the hydrophilic behavior of the material. Also the mechanical properties of the wet and dry film were assessed. Alongside this, 2.5% (wt/wt of dry film) of grapefruit seed extract (GSE), an antimicrobial agent, was added to the film‐forming solution just before casting and the ability of the plastic matrix to release the additive was then evaluated in vitro against 2 GSE‐susceptible microorganisms, Salmonella enteritidis and Listeria innocua. The results indicate that the developed matrix may be a promising food‐grade material for the incorporation of active substances. 相似文献
1000.
Alessandro Neri Maria Stella Simonetti Lina Cossignani P. Damiani 《European Food Research and Technology》1998,206(6):387-392
Separation of the six sub-fractions of triacylglycerols (TAG) from cocoa butter, three cocoa butter equivalents (CBEs: calvetta,
choclin and coberine) and their mixtures was carried out by silver ion high-performance liquid chromatography. The percentage
fatty acid composition of all these sub-fractions was then measured by high-resolution gas chromatographic analysis of the
methyl esters of the constitutive fatty acids. In particular, the percentage quantities of all acids in the fully saturated
sub-fraction of pure fats and some of their mixtures were evaluated as a function of the percentage CBEs added to cocoa butter
in order to devise multiple regression models. The aim was to obtain statistical tools for the identification and/or quantification
of added CBEs. The results obtained show the effectiveness of TAG sub-fraction percentage fatty acid composition data for
the purposes of research, as well as the potential use of stereospecific analysis of the same sub-fractions. In fact, the
stereospecific analysis of TAG fractions from cocoa butter and CBEs already carried out has enabled observation of the different
distributions of various fatty acids in the glycerol backbone of TAG from cocoa butter and the CBEs under study, and this
will certainly result in the development of more powerful and discriminating statistical models.
Received: 12 August 1997 / Revised version: 19 December 1997 相似文献