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521.
The subject of this review is the production of new-generation biofuels and fuels from wastes by cost effective medium temperature conversion processes. Recent literature results concerning pyrolysis at medium-temperature (mainly 300–450 °C) of biomasses, plastics and wastes are reviewed. The focus is on processes usable to maximize the production of liquids. Conclusions concern the relation of raw material composition and reaction temperature on the quality and quantity of liquid products. The main limitation of this approach is the high heteroatom content that is frequently present in the resulting fuels, particularly oxygen from biomass-derived fuels, but also nitrogen, sulphur and chlorine from waste derived fuels. For this reason, further refining treatment could be necessary, depending on the use of the resulting fuel.  相似文献   
522.
Hazelnut skins are a good example of agro-food by-products, potentially source of natural antioxidants and functional food ingredients, rich in polyphenols and dietary fibre. The chemical characterization performed in our study confirmed that fibre is the main component of hazelnut skin. Moreover, four different polyphenols-rich extracts and two fibre fractions were obtained by the processing of the skins. The functional activity of these extracts was verified using them as ingredients in media employed for the growth of two probiotic strains (Lactobacillus plantarum P17630 and Lactobacillus crispatus P17631). Starting from 0.01% (w/v), both soluble (SDF) and insoluble dietary fibre (IDF) significantly improved the bacterial growth during fermentation toward control. Both SDF and IDF showed a considerable increase in cryoprotection during lyophilisation, showing a similar effect to the inulin at the same concentration. Finally, we suggest this matrix as source of new functional fibres both for foods and nutraceutical products containing probiotic bacteria.  相似文献   
523.
Functional extracts from soybean have numerous health benefits deriving from their content in isoflavones, especially daidzein and genistein, natural antioxidant and estrogen-like (ES-like) molecules. However, soybeans denaturated dried extracts possess critical properties for industrial applications such as poor water-solubility and inadequate storage stability. The present research was aimed at developing a new sodium-carboxymethylcellulose (NaCMC) matrix by spray-drying to microencapsulate soy extracts obtaining enhanced technological and permeation properties. Microparticles (NaCMC-Iso) loaded with marketed soybeans extract (Iso), enriched in daidzein and genistein (about 90% w/w), were produced. Different liquid feeds, based on H2O/EtOH/acetone co-solvent systems, and various process parameters were tested to obtain a free-flowing and manageable powder with satisfying yield. The engineered NaCMC-Iso powders showed satisfying loading efficiency, high flow properties, good stability and enhanced technological properties. Interestingly, the in vitro dissolution and permeation rates were dramatically improved suggesting a higher bioavailability after the oral administration. The made-up powder appears a newsworthy ingredient of easier manipulation for enclosing in dietary supplements and nutraceutical products.  相似文献   
524.
Inulin behaved as a prebiotic to improve firmness of skim milk fermented by (a) pure cultures of Lactobacillus acidophilus (La), Lactobacillus rhamnosus (Lr), Lactobacillus bulgaricus (Lb) and Bifidobacterium lactis (Bl), (b) binary co-cultures of them with Streptococcus thermophilus (St), or (c) a cocktail containing all them. Inulin addition to co-cultures and cocktail enhanced products firmness, either after 1 day (D1) or 7 days (D7) of cold storage, likely due to the increase in microbial growth induced by metabolic interactions among lactic acid bacteria and partial inulin metabolization. Co-culture firmness did in fact range from 0.33 N without inulin (St-Lb) after D1 and 0.55 N with inulin (St-Lr) after D7. Also cocktail cultures exhibited high values of firmness, ranging, as an average, from 0.43 N (D1) to 0.46 N (D7), which suggests that they could have been potentiated by the reciprocal synergistic effects of microorganisms in complex mixture.  相似文献   
525.
526.
Polyphenols, the well known naturally occurring antioxidants, are the most abundant secondary metabolites in grape wastes. Herein we investigate several non-conventional extraction methods vs classic solid–liquid extraction (SLE) to obtain phenolic compounds from grape seeds and skins. We compared SLE, ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE) and high pressure and temperature extraction (HPTE) in term of extraction yield and antioxidant power of the extract. Solvent of choice between methanol and ethanol was the former, both for skins and seeds. Quali-quantitative analyses were performed using colorimetric and HPLC methods. The highest content in total polyphenols, o-diphenols and flavonoids, both for seeds (108.3, 47.0 mgGAE gDW−1, 47.2 mgCE gDW−1) and skins (34.2, 10.1 mgGAE gDW−1, 21.6 mgCE gDW−1) was obtained with HPTE working in a Parr reactor. While the highest antiradical power was determined in seeds extracts from MAE (78.6 μlextract μgDPPH−1). Prolonged extraction times (over 30 min) further increased the amount of total polyphenols, while progressively decreased the amount of flavonoids and the antiradical power.  相似文献   
527.
Tested 80 C57BL/6J, DBA/2J, and SEC/1ReJ mice with septal or control lesions for exploratory behavior, shuttle-box avoidance learning, discriminated avoidance, and maze-learning ability. Control DBA and SEC Ss normally displayed low levels of exploratory behavior and efficient avoidance and maze learning. High exploratory activity and low avoidance and maze learning were characteristically shown by C57 controls. All strains with septal lesions increased levels of exploratory and avoidance behaviors. In contrast, following septal lesions the 3 strains performed more poorly in discriminated-avoidance and maze learning. It is concluded that differences in septal function-e.g., in level of response inhibition-do not substantially account for the learning differences evident between these strains. (19 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
528.
Multiple correspondence analysis (MCA) is a multivariate method for analyzing multidimensional contingency tables. General software procedures to perform MCA are available. Among them SAS Proc CORRESP, SPAD CORMU procedure and the mca function of the MASS library in S-PLUS are probably the most used. However, CORRESP and CORMU output is different from that of mca function. The aim of this short note is showing how to obtain from mca function results compatible with those achieved with SAS or SPAD. A modified code is proposed in order to obtain the same coordinate system computed by SAS and SPAD. Moreover, the computation of the contributions of the levels of the factors to the inertia explained by each axis, the squared cosine of each factor level and the re-evaluation of the inertia explained by each axis have been added in order to improve the interpretations of the results of the decomposition.  相似文献   
529.
For the first time, the standardization for pH measurements is here implemented in the domain of superpermittive media. The nonaqueous solvent studied is formamide (epsilon = 109.5 at 298.15 K) for which three primary standards and two secondary standards have been determined, whose excellent internal consistency has also been demonstrated by specific cell measurements. A comparison of the pH scale in formamide with the aqueous scale has been duly tried by accounting for the primary medium effect on the H+ ion. Furthermore, as a result of an ad hoc supplementary systematic investigation, three salt bridges of appropriate level of equitransference in formamide, that is, NH(4)Cl, NH(4)Br, and NH(4)I, have been characterized for abating the liquid junction potentials intervening in the pH-measuring cell to enable the user to carry out regular pH measurements and related controls.  相似文献   
530.
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