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991.
Use of infrared ocular thermography to assess physiological conditions of pigs prior to slaughter and predict pork quality variation 总被引:1,自引:0,他引:1
Angela V. Weschenfelder Linda Saucier Xavier Maldague Luiene M. Rocha Allan L. Schaefer Luigi Faucitano 《Meat science》2013
Infrared thermography (IRT) body temperature readings were taken in the ocular region of 258 pigs immediately before slaughter. Levels of lactate were measured in blood taken in the restrainer. Meat quality was assessed in the longissimus dorsi (LD), semimembranosus (SM), and adductor muscles. Ocular IRT (IROT) temperature was correlated with blood lactate levels (r = 0.20; P = 0.001), with pH taken 1 hour postmortem (pH1: r = − 0.18; P = 0.03) and drip loss (r = 0.20; P = 0.02) in the LD muscle, and with pH1 in the SM muscle (r = − 0.20; P = 0.02). Potentially, IROT may be a useful tool to assess the physiological conditions of pigs at slaughter and predict the variation of important meat quality traits. However, the magnitude of the correlations is rather low, so a further development of image capture technique and further studies under more variable preslaughter conditions ensuring a larger pork quality variation are needed. 相似文献
992.
Biodiversity of complexes of mycotoxigenic fungal species associated with Fusarium ear rot of maize and Aspergillus rot of grape 总被引:2,自引:0,他引:2
Logrieco A Moretti A Perrone G Mulè G 《International journal of food microbiology》2007,119(1-2):11-16
Fusarium ear rot of maize and Aspergillus rot of grape are two examples of important plant diseases caused by complexes of species of mycotoxigenic fungi. These complexes of species tend to be closely related, produce different classes of mycotoxins, and can induce disease under different environmental conditions. The infection of maize and grape with multiple fungal species and the resulting production of large classes of mycotoxins is an example of mutual aggressiveness of microorganisms toward host species as well as to humans and animals that eat feed or food derived from the infected and contaminated plants. Infection of crop plant with a complex of microbial species certainly represents a greater threat to a crop plant and to human and animal health than infection of the plant with a single fungal species. 相似文献
993.
Marcello De Falco Alberto Giaconia Luigi Marrelli Pietro Tarquini Roberto Grena Giampaolo Caputo 《International Journal of Hydrogen Energy》2009
A novel hybrid plant for the production of a mixture of methane and hydrogen (17 vol%) from a steam-reforming reactor whose heat duty is supplied by a concentrating solar power (CSP) plant by means of a molten salt stream is here presented. 相似文献
994.
Angela Mari Idolo Tedesco Annunziata Nappo Gian Luigi Russo Antonio Malorni Virginia Carbone 《Food chemistry》2010
In Annurca apples, a southern Italian variety, polyphenols were studied. The phenolic composition of Annurca apple peel was determined by HPLC coupled with electrospray negative ionisation multistage ion trap mass spectrometry (HPLC/ESI–ITMSn). In addition, the antiproliferative and pro-apoptotic activities of peel extracts enriched in polyphenols and prepared from Annurca (APE), Red Delicious (RDPE) and Golden Delicious (GPE) varieties were evaluated on an HL-60 cell line. APE exhibited the highest total phenol content among the three apple cultivars tested, as determined by Folin–Ciocalteau’s procedure and HPLC–UV analysis. APE also showed higher amounts of chlorogenic acid, procyanidins, flavonols, dihydrochalcones and cyanidin-3-O-galactoside than GPE or RDPE. All three apple extracts were able to significantly decrease cell viability, from 50% to 80%, with APE appearing the most effective, while GPE was the least cytotoxic among the three samples. Similarly, APE and RDPE induced a significant increase of caspase-3 activity, whose activation represents a hallmark of apoptosis. 相似文献
995.
Luigi Montanari Simona Floridi Ombretta Marconi Michela Tironzelli Paolo Fantozzi 《European Food Research and Technology》2005,221(1-2):175-179
The effect of the double decoction mashing method (method A) and the single decoction plus infusion mashing method (method B) on brewing were compared. The trials were carried out with the same raw material (malt and a minor amount of corn as adjunct) on an industrial-scale plant. The effects of mashing methods A and B were evaluated in wort and beer samples obtained with the high gravity system. The analytical parameters of the worts and beers produced and the economic aspects of production (yield, beer quality, time and energy) were discussed. The results showed no considerable differences in beer quality, while a significant difference was observed in the composition of fermentable sugars of worts. Method B gave a wort with a higher content of fermentable sugars which were converted to alcohol during fermentation; therefore, it allowed to obtain a higher beer volumetric yield of the same quality while saving time and energy. 相似文献
996.
Margita Utczás Francesco Cacciola Daniele Giuffrida Marina Russo Ivana Bonaccorsi Paola Dugo Luigi Mondello 《Food Analytical Methods》2018,11(11):3053-3070
Food waste production generated by large distribution represents an emerging issue due to the large polluting impact and, at the same time, due to the enormous increase of nutrients’ need worldwide. Overripe fruits are considered as “food wastes” despite they could be yet rich sources of food ingredients and bioactives, such as carotenoids and polyphenols. In this work, a phytochemical screening of 20 selected overripe vegetables and fruits was accomplished by liquid chromatography coupled to photodiode array and mass spectrometry detection. The obtained results showed that the low-sugar-content fruits and vegetables had a higher bioactive content compared to the high-sugar fruits; in particular, tomato, wild swiss chard, green bell pepper, and lettuce leaves were the richest in bioactive phytochemicals. Green bell peppers showed the highest pigment content (875.3 mg/kg), whereas tomato, wild swiss chard, and lettuce leaves showed the highest polyphenol contents, 4541.9, 1692.4, and 712.9 mg/kg, respectively. This is the first work where a large-scale monitoring of bioactives in overripe fruits was carried out and two mixtures of fresh and dry material for animal feed are presented. 相似文献
997.
Isabella Nicotera Apostolos Enotiadis Kristina Angjeli Luigi Coppola Dimitrios Gournis 《International Journal of Hydrogen Energy》2012
Synthetic and natural smectite clays, with different structural and physical parameters, were tested as nanofillers for the creation of Nafion nanocomposites. The solution intercalation method has been successfully applied for incorporation of layered materials into the polymer, while the effect of the solvent, temperature and filler loading were examined in order to determine the optimum conditions for the preparation of highly homogeneous composites. 相似文献
998.
Aroma compounds and sensory characteristics as biomarkers of quality of differently processed Tunisian virgin olive oils
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Manel Issaoui Ines Gharbi Guido Flamini Pier Luigi Cioni Alessandra Bendini Tullia Gallina Toschi Mohamed Hammami 《International Journal of Food Science & Technology》2015,50(8):1764-1770
The influence of the extraction system (continuous vs. discontinuous) and the degree of freshness of olives on the chemical composition and the quality of Chemlali and Chétoui virgin olive oil has been studied. Analytical data mainly concerning the volatile and sensory profiles revealed statistically significant differences in relation to the extraction system. All quality indices and sensory characteristics showed statistically significant differences associated with the degree of freshness of fruits. These results further confirm the general consensus that volatile compounds can be very useful as biomarkers of the quality of virgin olive oil and show correlations with the sensory characteristics. 相似文献
999.
Valeria Menga Clara Fares Antonio Troccoli Luigi Cattivelli & Antonietta Baiano 《International Journal of Food Science & Technology》2010,45(1):7-16
In order to assess the effect of genotype, location and their interaction on total phenolic content (TPC) of chemical extracts, the whole grains of durum and soft wheat, oat, barley and triticale were evaluated. Data showed differences in phenolic content of chemical extracts among cereal species and the analysis of variance confirmed the key role of location. Besides TPC and trolox equivalent antioxidant capacity (TEAC) values assessed by chemical extraction were compared with those obtained with an in vitro digestive enzymatic extraction. Differences were found between methanolic and enzymatic extracts, and data confirmed that enzymatic technique enhanced extraction of antioxidants but pointed out lesser differences among cereal types. The breads obtained by flours enriched with different levels of bran were also evaluated. Chemical extracts highlighted the increasing levels of antioxidants according to bran enrichments, without pointing out changes caused by baking. The enzymatic extraction instead did not show differences regarding to bran enrichments, but documented a loss in antioxidant properties of breads in respect to corresponding flours. On the other hand the scarce differences between flours and corresponding breads did not allow asserting that baking modified the TPC and TEAC, independently of the extraction methods used. Indeed, during baking process, also the observed phenolic acids profile variations did not vary the antioxidant properties of breads. 相似文献
1000.