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71.
Three yeast strains capable of utilizing methanol as sole carbon and energy source were isolated. Two were classified as Candida boidinii, while the third belonged in the genus Pichia. From these three strains, four alcohol oxidases genes were identified and the sequences of the coding regions were determined: one from each Candida boidinii (aox0673 and aox0680) and two from Pichia sp. 159 (aoxA and aoxB). Methanol induces both alcohol oxidases in Pichia sp. 159: the levels of aoxA and aoxB mRNA reach about 100% and 300%, respectively, of that of his4 mRNA. aoxA, but not aoxB, is expressed at a low level in the presence of glucose. The newly described alcohol oxidases have proper dinucleotide binding sites and PTS1-like C-terminal tripeptides, identified as important elements for peroxisomal localization. 相似文献
72.
Pasqua Caccialupi Luigi R. Ceci Rosa A. Siciliano Domenico Pignone Alfonso Clemente Gabriella Sonnante 《Food chemistry》2010
A full-length cDNA, encoding a Bowman-Birk protease inhibitor (BBI), was isolated from lentil immature seeds. The deduced amino acid sequence was longer than that of the BBI extracted from lentil seeds and contained two binding sites; the first inhibitory site inhibits trypsin whereas the second one inhibits chymotrypsin. In order to characterize this lentil BBI, a longer (complete) and its C-terminally processed (mature) form were heterologously expressed in the yeast Pichia pastoris. The recombinant BBI proteins proved to be active against trypsin and chymotrypsin, showing Ki values at nanomolar levels. Mass spectrometry analysis revealed that complete BBI was composed of an array of molecular masses, whereas mature BBI showed the presence of a major peak of the expected size. The effects of mature BBI on the growth of human colon adenocarcinoma HT29 and colonic fibroblast CCD-18Co cells were evaluated. Lentil BBI was able to inhibit the growth of such cells at concentrations higher than 19 μM, in a concentration-dependent manner; by contrast, the CCD18-Co cells were unaffected. These data broaden our knowledge of the beneficial biological activities of naturally-occurring BBI proteins and address the need for systematic evaluation of natural variants in order to design novel strategies in preventive medicine. 相似文献
73.
Barbara Lanza Maria Gabriella Di Serio Emilia Iannucci Francesca Russi & Paolo Marfisi 《International Journal of Food Science & Technology》2010,45(1):67-74
In the present study, we evaluated chemical, nutritional, sensory and textural characteristics of table olives of an Italian double-aptitude olive cultivar ( Olea europaea L. cv. Intosso d'Abruzzo ). The aim of this work was to focus some physico-chemical characteristics of this end product in order to enhance the value of this fruit from a nutritional point of view. These table olives are fruits with an appreciable content of fibre (2.6 g/100 g) and natural antioxidants such as polyphenols (167.8 mg/100 g) and α-tocopherol (6.44 mg/100 g). In this cultivar, oil content is high (17.5 g/100 g), such as MUFA (13.6 g/100 g). The protein content is low (1 g/100 g), but nutritional quality is high for the presence of essential amino acids. 相似文献
74.
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
75.
76.
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
77.
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
78.
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
79.
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