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71.
Valentina Di Egidio Nicoletta Sinelli Gabriella Giovanelli Agostina Moles Ernestina Casiraghi 《European Food Research and Technology》2010,230(6):947-955
Fifteen micro-fermentation trials were conducted during the 2008 vintage harvest in the Valtellina (Northern Italy) viticultural
area. During fermentation, the spectra were achieved in the near and mid-infrared region by a FT-NIR spectrometer and a FT-IR
spectrometer, respectively. Samples were also analysed by using chemical methods to evaluate sugars (glucose and fructose),
alcohols (ethanol and glycerol) and phenolic compounds (total phenolics, total anthocyanins and total flavonoids). The pretreated
spectral data were processed using principal component analysis. After feature selection by the algorithm SELECT, linear discriminant
analysis (LDA) was applied to spectral data as a classification technique, to predict the fermentation stage from initial
to final phase. Moreover, partial least square regression was used to predict sugar content, ethanol, glycerol and phenolic
compounds simultaneously. LDA results, characterised by a high percentage of correct classification (87% and 100% as average
value in prediction for NIR and MIR spectroscopy, respectively), showed that samples belonging to a particular fermentation
step could be correctly classified. Good calibration models for the prediction of the main compositional changes during alcoholic
fermentation were obtained with both FT-NIR and FT-IR, suggesting that either instruments could be used to evaluate online
and simultaneously these compounds in red wine. 相似文献
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73.
Andrea Biffis Cristina Tubaro Gabriella Buscemi Marino Basato 《Advanced Synthesis \u0026amp; Catalysis》2008,350(1):189-196
1 We report on a novel reaction protocol for the coupling of arenes with alkynes (the Fujiwara reaction), yielding products of formal trans‐hydroarylation of the triple bond. The protocol makes use of a chelating N‐heterocyclic dicarbene palladium(II) complex as catalyst and allows us to perform the reaction in a few hours with only 0.1 mol % catalyst yielding the trans‐hydroarylation product in high yields and with excellent selectivity. We discuss the applicability of this reaction protocol, which appears at present quite general with respect to the alkyne, albeit limited to electron‐rich arenes. We also present the results of catalyst optimisation with respect to the nature of the nitrogen substituents in the carbene units, of the bridging group between the carbene units and of the coordinated anionic ligands. Finally, we also discuss the catalytic performance of a related chelating dicarbene complex of platinum(II). 相似文献
74.
Galvano F Pietri A Bertuzzi T Gagliardi L Ciotti S Luisi S Bognanno M La Fauci L Iacopino AM Nigro F Li Volti G Vanella L Giammanco G Tina GL Gazzolo D 《Molecular nutrition & food research》2008,52(4):496-501
During 2006, 82 samples of human mature milk were collected at Italian hospitals and checked for aflatoxin M1 (AFM1) and ochratoxin A (OTA) by immunoaffinity column extraction and HPLC. AFM1 was detected in four (5%) of milk samples (ranging from < 7 ng/L to 140 ng/L; mean level: 55.35 ng/L); OTA was detected in 61 (74%) of milk samples (ranging from < 5 ng/L to 405 ng/L; mean level: 30.43 ng/L. OTA levels were significantly higher (p less, not double equals 0.05) in milk of habitual consumers of bread, bakery products and cured pork meat. No other statistically significant differences were observed although habitual consumers of pasta (p = 0.059), cookies (p = 0.061) and juices (p = 0.063) had mean contamination values of OTA higher than the moderate consumer. The very few AFB1 positive samples did not allow statistical comparisons. The present study confirms that the occurrence of OTA in human milk is related to maternal dietary habits. The findings support the possibility of dietary recommendations to woman, during pregnancy and lactation, aimed to tentatively reduce the OTA contamination of human milk. 相似文献
75.
Beate Kettlitz Gabriele Scholz Viviane Theurillat Jrg Cselovszky Neil R. Buck Sue O Hagan Eva Mavromichali Katja Ahrens Karin Kraehenbuehl Gabriella Scozzi Markus Weck Claudia Vinci Marta Sobieraj Richard H. Stadler 《Comprehensive Reviews in Food Science and Food Safety》2019,18(3):738-752
The acceptance of many foods is related to traditional cooking practices, which create taste and texture and are important to digestibility, preservation, and the reduction of foodborne illnesses. A wide range of compounds are formed during the cooking of foods, a number of these have been shown to lead to adverse effects in classical toxicological models and are known as food processing contaminants (FPC). It is essential that the presence and effects of such compounds alone and in combination within the diet are understood such that proportionate risk management measures can be developed, while taking a holistic view across the whole value chain. Furan and alkylfurans (principally 2‐ and 3‐methylfuran) are highly volatile FPC, which are formed in a wide range of foods at low amounts. The focus of research to‐date has been on those foods, which have been identified to be most consequential in terms of being sources of exposure, namely jarred and canned foods for infants and young children (meals and drinks) and coffee (roast and ground, soluble). This report presents (i) new industry data on the occurrence of furan and methylfurans in selected food categories following previous coffee studies, (ii) the most salient parameters that impact furan formation, and (iii) aspects of importance for the risk assessment. 相似文献
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Lopez Daniel Andres Sanchez Chagas Luciana Gomes Batista Aline Domingues Guaita Maria Gabriella Detone Amorin Luís Henrique Cardozo da Silva Paulo Rogério Catarini Yamanishi Gustavo Zaia Dimas Augusto Morozin de Santana Henrique Urbano Alexandre 《Journal of Materials Science: Materials in Electronics》2021,32(13):17462-17472
Journal of Materials Science: Materials in Electronics - The increasing demand for lithium-ion batteries has stimulated the investigation of new compounds in order to reduce the costs and the... 相似文献
79.
Lucia Marseglia Sara Manti Gabriella D’Angelo Antonio Nicotera Eleonora Parisi Gabriella Di Rosa Eloisa Gitto Teresa Arrigo 《International journal of molecular sciences》2015,16(1):378-400
Obesity, a social problem worldwide, is characterized by an increase in body weight that results in excessive fat accumulation. Obesity is a major cause of morbidity and mortality and leads to several diseases, including metabolic syndrome, diabetes mellitus, cardiovascular, fatty liver diseases, and cancer. Growing evidence allows us to understand the critical role of adipose tissue in controlling the physic-pathological mechanisms of obesity and related comorbidities. Recently, adipose tissue, especially in the visceral compartment, has been considered not only as a simple energy depository tissue, but also as an active endocrine organ releasing a variety of biologically active molecules known as adipocytokines or adipokines. Based on the complex interplay between adipokines, obesity is also characterized by chronic low grade inflammation with permanently increased oxidative stress (OS). Over-expression of oxidative stress damages cellular structures together with under-production of anti-oxidant mechanisms, leading to the development of obesity-related complications. The aim of this review is to summarize what is known in the relationship between OS in obesity and obesity-related diseases. 相似文献
80.