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11.
The study of shapes is a difficult topic, but it is becoming more and more important as computer vision techniques are already crucial in many research fields. Concretely, the variability of shapes is the basis for many criteria of symptom definition in medical diagnosis. This article introduces a stochastic order to address the variability of star-shaped sets. The main properties of the order are analyzed. An example of an application to hypothesis testing in medical diagnosis is also provided. Namely, we study if there are significant differences between healthy and diseased corneal endothelia with respect to cell shapes by means of ocular images.  相似文献   
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The content of sterols and erythrodiol + uvaol was studied in 273 virgin olive oil samples from 40 mills in five olive‐growing zones of Extremadura (Spain). An analysis of variance showed significant differences at a confidence level of 95 % between the different zones in each of the main sterols and in the sum of erythrodiol + uvaol. The results of a linear discriminant analysis, considering the different olive‐growing areas as categorical dependent variables and the different sterols as independent variables, explained 78.2 % of the variance with the first two discriminant functions. The resulting model correctly classified 86.9 % of the samples analysed. A validation study was conducted to verify the goodness of the discriminant analysis, resulting in 79.3 % of the new samples used for validation being correctly classified. In the graphical representation of the different groups studied considering the proposed model's first two discriminant functions, the centroids of the Sierra Norte de Cáceres, Vegas del Guadiana and Tierra de Barros olive‐growing zones were clearly separated, but this was not the case for the other two zones—La Serena and La Siberia.  相似文献   
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This study reports the low‐temperature and clean fabrication of porous poly(lactic acid) (PLA) through solid‐state foaming using various mixtures of ethyl lactate (EL) and supercritical CO2 (scCO2) as the blowing agent. Results showed that adding a small amount of EL (up to 0.2% molar fraction) to scCO2 enhanced the plasticizing effect of the blowing agent mixture. As a direct consequence, at an operating temperature of 35 °C, PLA foams could be manufactured with homogeneous morphology, density as low as 0.09 ± 0.01 g cm?3, mean pore sizes up to 519.0 ± 205.0 µm and pore densities in the range 2.0 × 105 to 3.4 × 108 pores cm?3. Conversely, at a temperature of 40 °C, an increase of plasticizer concentration in the blowing agent mixture up to 0.2% promoted the crystallization of the polymer during sorption stage and, consequently, foaming was slightly reduced. © 2013 Society of Chemical Industry  相似文献   
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The effects of microbial transglutaminase (TGM) on the viscoelastic profile of wheat flour doughs when added singly and in combination with hydrocolloids—hydroxypropylmethylcellulose (HPMC) and a high ester pectin (GENU pectin type BIG, or BIG)—, amylolytic (-amylase) and non amylolytic enzymes (xylanase) and an emulsifier [diacetyl tartaric acid ester of mono-diglycerides (DATEM)] have been investigated by applying response surface analysis to a Draper-Lin small composite design of formulated dough samples. In spite of the major effects on mixing, textural, extensional and viscometric parameters, which were provided by hydrocolloid/surfactant combinations, incorporation of TGM into dough formulas improved some viscoelastic properties. TGM, when added to DATEM and/or HPMC-containing doughs, induced synergistic effects on mixing parameters, resulting in increased water absorption, development time and stability. Highly cohesive doughs with improved water holding capacity and gluten strength during mixing and fermentation, and suitable pasting behaviour during cooking were achieved using TGM/BIG/DATEM mixtures, mainly associated with suitable interactions of the pairs TGM/DATEM and DATEM/BIG.  相似文献   
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We synthesized crystalline Erbium Er3+ and Ytterbium Yb3+ codoped -Lu2O3 nanolayers on SiO2 microspheres using the modified Pechini method. Two different kinds of precursors, nitrates and chlorides, have been used leading to a layer-to-layer morphology and necklaces structures, respectively. In both cases, the size of nanocrystallites constituting the optical active layer is around 5 nm. We performed X-ray powder diffraction to confirm the cubic crystalline structure of the sesquioxides layer. High resolution transmission electron microscopy analyses corroborate the crystalline nature of the layer. The optical emission of Er3+ in the visible range has been recorded.  相似文献   
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The effect of treatment with α‐galactosidase, tannase or a cell‐wall‐degrading enzyme complex under optimal conditions of pH, temperature and length of incubation time on the chemical composition and nutritive utilisation of protein and carbohydrates from pea (Pisum sativum L.) flour was studied. Soaking of pea flours in combination with enzyme treatment led to reductions of 77–90% in the levels of α‐galactosides, and of 60–80% in the levels of trypsin inhibitor activity, increasing the content of total available sugars, which was highest in the pea flour treated with the cell‐wall‐degrading enzyme complex. All the treatments assayed caused a significant improvement in daily food intake, whereas the nutritive utilisation of protein was not increased in any of the pea products tested when compared to the raw pea flour. However, all the soaking and enzymatic treatments led to a significant improvement in daily weight gain associated with a higher dietary intake of food and total available sugars. Copyright © 2007 Society of Chemical Industry  相似文献   
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The darkening step in ripe olive processing can be accelerated by using different metal cations, particularly cobalt, manganese and iron, in the aeration liquid. It was found that manganese and iron ions increased the rate of the darkening reaction as their content in the liquid increased from zero to 9 mM. Manganese cations only had a catalytic effect on the darkening reaction, while iron ions also fixed the dark colour formed when olives were bottled and sterilized. However, the rate of oxidation of the orthodiphenols in the olive flesh (hydroxytyrosol and caffeic acid) was slightly modified when manganese or iron was added to the aeration liquid. The better dark surface colour obtained when manganese or iron ions were added to the aeration liquid remained after bottling and sterilization of olives in a ferrous gluconate solution. These results suggest that manganese could be used to catalyse the darkening reaction since this cation is generally recognized as safe.  相似文献   
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