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991.
The present study focused on the application of pulsed electric fields (PEF) as an innovative pre-treatment technique to improve the recovery of polyphenols from two food by-products, cocoa bean shell (CBS) and coffee silver skin (CS). The effect of the different operating parameters on the extraction of polyphenols was optimised using the response surface methodology statistical approach. The optimised methodology was compared with conventional extraction and applied to several CBS and CS samples to classify the samples according to origin, variety and industrial treatment. PEF-assisted extraction had higher (approximately 20%) recovery yields of polyphenols and methylxanthines than conventional extraction. Finally, the results highlighted that the composition of bioactive compounds from different extracts of CBS and CS and their antioxidant properties depended on the origin, variety and industrial processing of the raw material. These by-products may be a promising source of natural compounds, with potential applications on food and health sectors.  相似文献   
992.
Microwave-assisted sample digestion and inductively coupled plasma-mass spectrometry (ICP-MS) were considered for exploring major and trace elements in the Mediterranean Sepia ink. The present work aims to (a) fully validate the employed ICP-MS method and compare the Hg determinations by ICP-MS with those obtained by a direct mercury analyzer (DMA) and (b) interpret quantitative data by chemometrics and perform a risk/benefit analysis for assessing the quality/safety of Sepia ink. DMA gave Hg determinations similar to the ICP-MS counterpart (p > 0.05), confirming its reliability for food analysis. Sepia ink demonstrated to be both a reservoir of “healthy” elements and a sink of potential toxic metals. In fact, a good contribution of major and essential trace metals to the established RDAs was revealed, and, at the same time, potentially toxic elements showed to accumulate depending upon the environmental conditions, although not representing a risk for human consumers.  相似文献   
993.
This article is a critical overview of recent contributions on the dietary corrections and the foods that have been claimed to delay or hinder the onset of diabetic nephropathy (DN) and its progression to end-stage renal disease. Innovative dietary and behavioral approaches to the prevention and therapy of DN appear to be the most captivating in consideration of the rather well-established protocols for glucose and blood pressure control in use. In addition to restricted caloric intake to contrast obesity and the metabolic syndrome, adjustments in the patient's macronutrients intake, and in particular some degree of reduction in protein, have been long considered in the prevention of DN progression. More recently, the focus has shifted to the source of proteins and the content of glycotoxins in the diet as well as to the role of specific micronutrients. Few clinical trials have specifically addressed the role of those micronutrients associated with diet proteins that show the most protective effect against DN. Research on clinical outcome and mechanisms of action of such micronutrients appears the most promising in order to develop both effective intervention on nutritional education of the patient and selection of functional foods capable of contrasting the onset and progression of DN.  相似文献   
994.
Lactobacillus plantarum LB1 and Lactobacillus rossiae LB5, isolated from wheat germ and selected based on the kinetics of acidification, were used as starters for the manufacture of sourdough fermented wheat germ. A bread containing sourdough fermented wheat germ as an ingredient (SFWGB) was compared to breads made with (raw wheat germ bread, RWGB) or without (wheat flour bread, WFB) raw wheat germ. The higher concentration of free amino acids mainly differentiated SFWGB from WFB and RWGB. The in vitro protein digestibility of WFB was the highest, even if sourdough fermentation of wheat germ attenuated the difference. Phytase and antioxidant activities of SFWGB were highest. The specific volume and cell-total areas were also the highest for SFWGB. As determined by texture profile analysis, the values of hardness, resilience and fracturability of breads containing wheat germ were lower than those found in WFB. The crust lightness showed a decrease from WFB to SFWGB. As determined by sensory analysis, SFWGB had mainly acid taste and flavour and resulted more salty. Sourdough fermented wheat germ is an ingredient able to enhance nutritional, texture and sensory properties of bread.  相似文献   
995.
The use of two recently developed diglycolamide-based extractants for the co-separation of trivalent actinides (An(III)) and lanthanides (Ln(III)) is described and compared to the well-known extractant TODGA (N,N,N’,N’-tetraoctyl diglycolamide). The addition of one or two methyl groups to the central methylene carbon atoms of the TODGA molecule leads to a reduction of the extraction efficiency for An(III) and Ln(III). This is attributed to a lower complex formation constant, which was proven by Time-Resolved Laser Fluorescence Spectroscopy (TRLFS). Conditional stability constants were determined by solvent extraction and TRLFS. The reduction in extraction efficiency leads to overall reduced distribution ratios of all tested metal ions, including Sr(II). The reduced Sr(II) extraction is beneficial as a co-extraction in a solvent extraction process could be avoided, while an efficient extraction of the desired An(III) and Ln(III) is still achieved. Furthermore, this might be a benefit, as the stripping behavior might be improved, even at moderate nitric acid concentrations. The slightly higher affinity of the diglycolamides towards Eu(III) over Am(III) is represented by all ligands, although the selectivity is rather low. This results in promising extraction properties of the modified diglycolamides towards the development of continuous solvent extraction processes.  相似文献   
996.
997.
The study aims at investigating the suitability of absorbance at 225 nm as an objective means to evaluate virgin olive oil (VOO) bitterness. Calculation of oleuropein score (OLS) using a standard curve instead of the so far employed K225 value is proposed and a “taste index” based on the total phenol content determined by fluorimetry is examined as a complementary tool. Data from sensory evaluation of a series of VOO samples and RP-HPLC determination of phenolic compounds using diode array, fluorimetric or MS detection supported the applicability and merits of the introduced criteria. Phenol profiling using fluorescence detection (280 nmexcitation/320 nmemission) became useful regarding oil bitterness. The presence of the non-fluorescent elenolic acid at 225 nm, indicated that the K225 value is influenced by the presence of this non-bitter compound found at significant levels even in fresh oils. Our finding offers further ground to our proposal for the calculation of the “taste index”.  相似文献   
998.
Measurements of dynamic-surface-tension responses to harmonic surface perturbations, in the low-frequency range, are reported for aqueous solutions of n-dodecyl-dimethyl-phosphine-oxide. From the primary observed results of the steady-state surface oscillation behaviour, the inherent surface dilational modulus is determined at different frequencies, at various concentrations up to the critical micellar concentration and at three temperatures (i.e., at T=15, 25 and 35 °C). The obtained experimental values are successfully interpreted in terms of the diffusion-controlled model. The experiments grant reliable information about the constitutive dynamic properties of air-liquid single interfaces.  相似文献   
999.
Editor's note:The diversification of the SoC market has increased the need for domain-specific programmable platforms that can be tailored to postfabrication products. This article presents a design case study on the interconnect for such a programmable platform, as part of the Morpheus project.—Li-Shiuan Peh, Princeton University  相似文献   
1000.
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