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排序方式: 共有1591条查询结果,搜索用时 15 毫秒
991.
Fabio Coloretti Giulia Tabanelli Cristiana Chiavari Rosalba Lanciotti Luigi Grazia Fausto Gardini Chiara Montanari 《Meat science》2014
The aim was to evaluate the effect of wine addition during manufacturing of dry fermented sausages, in terms of safety aspects (biogenic amine accumulation), aroma profile and sensory characteristics. Three batches of salami were produced: without wine addition and with 7.5% or 15% (v/w) of white wine. The fermented sausages showed characteristics that can increase product diversification. Some of the sensory features (i.e. increased salty perception) can represent an important strategy because of the trend to reduce salt intake for health reasons. The presence of wine immediately reduced the pH and is a source of ethanol, which can have an inhibitory effect against undesirable microflora. The microbiological results observed regarding Enterobacteriaceae and enterococci were encouraging. The addition of wine did not negatively affect the ripening time or increase the presence of biogenic amines. The samples containing wine showed reduced concentrations of putrescine. 相似文献
992.
C Elvio M Luigi F Ludovico CM Fabio C Alessandro DL Francesco R Giustino S Nicola 《Canadian Metallurgical Quarterly》1997,61(10):850-854
Severe myocardial dysfunction, characterized by global hypokinesis, or akinetic areas with hypokinesis of the remaining wall, and a very low ejection fraction (EF), has been considered to be a contraindication for coronary revascularization (CABG). However, myocardial scintigraphy and echo-stress data have shown that hypo- or akinetic areas can regain their contractility. Therefore, we expanded the indications for CABG, and performed operations even upon patients who were waiting for a heart transplant. Between January 1993 and June 1995, among 352 patients who underwent CABG, 85 had highly depressed left ventricular function. Their resting EF was lower than 0.35, and in 27 it was lower than 0.25. Viable areas of myocardium were found in all of the patients through the combination of scintigraphy and dobutamine-echocardiography: these areas depended on significant coronary lesions. The mean age of the patients was 48.2 years (range 33-62 years); angina was present in 62 patients. A mean of 3.1 grafts/patient were implanted; enoximone was used in all but 5 patients upon weaning from cardiopulmonary bypass; intra-aortic balloon pump was used in 9 cases. Operative mortality was 10.6% (9 patients), due to low-output syndrome in 5, acute myocardial infarction in 2, cerebral damage in 1, and respiratory failure in 1. At the 6-month follow-up, EF was improved in all but 7 patients, in whom it remained unchanged. Scintigraphic and echocardiographic tests revealed good function in most of the areas that had been previously recognized as hypo- or akinetic. These results suggest that the indications for standard myocardial revascularization can be expanded, and a promising option can be offered to patients who may otherwise be destined to wait for an uncertain transplantation. 相似文献
993.
Application of response surface methodology to evaluate the effect of dry‐spinning parameters on poly (ε‐caprolactone) fiber properties 下载免费PDF全文
Bahareh Azimi Parviz Nourpanah Mohammad Rabiee Shahram Arbab Maria Grazia Cascone Andrea Baldassare Luigi Lazzeri 《应用聚合物科学杂志》2015,132(24)
Poly (ε‐caprolactone) fibers were prepared by dry‐spinning method. The effect of processing parameters on linear density, mechanical, and morphological properties of fibers was investigated using the response surface methodology (RSM). This method allowed evaluating a quantitative relationship between polymer concentrations, spinning speed, and draw ratio on the properties of the fibers. Polynomial regression model was fitted to the experimental data to generate predicted response. The results were subjected to analysis of variance to determine significant parameters. It was found that all three parameters had significant effect on linear density of fibers. Combined effect of concentration and spinning speed was observed in which the linear density of fiber was more sensitive to changes in the solution concentration at lower spinning speed. Polymer concentration had the largest influence on the mechanical properties of fibers. An average cross‐sectional radius of fibers was affected by concentration and draw ratio in opposite manner. Among all three parameters, only polymer concentration had significant effect on circularity of fiber cross sections. By applying the RSM, it was possible to obtain a mathematical model that can be used to better define processing parameters to fabricate dry‐spun PCL fiber in a more rational manner. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42113. 相似文献
994.
It is shown that reported doping functions for apparent band-gap narrowing (ABGN) in silicon that are written in the Slotboom and De Graaff's form (Slotboom, De Graaff, Solid-State Electron. 19 (1976) 857) can be set in the Dhariwal and Ojha's form (Dhariwal, Ojha, Solid-State Electron. 25 (1982) 909) at all dopings without any significant deviation in their capability of fitting the experimental data. The use of the Dhariwal and Ojha's form is preferable because it allows for a straightforward application of the depletion approximation in the non-uniformly doped regions of silicon devices like ion-implanted and diffused solar cells, facilitating the device performance modeling and analysis. This is demonstrated by an application to the internal spectral responses of two ion-implanted silicon solar cells and a comparison with a modeling method which does not use the depletion approximation. 相似文献
995.
Yupeng Wu Guohui Gan Anne Verhoef Pier Luigi Vidale Raquel Garcia Gonzalez 《Applied Thermal Engineering》2010,30(16):2574-2583
Results from both experimental measurements and 3D numerical simulations of Ground Source Heat Pump systems (GSHP) at a UK climate are presented. Experimental measurements of a horizontal-coupled slinky GSHP were undertaken in Talbot Cottage at Drayton St Leonard site, Oxfordshire, UK. The measured thermophysical properties of in situ soil were used in the CFD model. The thermal performance of slinky heat exchangers for the horizontal-coupled GSHP system for different coil diameters and slinky interval distances was investigated using a validated 3D model. Results from a two month period of monitoring the performance of the GSHP system showed that the COP decreased with the running time. The average COP of the horizontal-coupled GSHP was 2.5. The numerical prediction showed that there was no significant difference in the specific heat extraction of the slinky heat exchanger at different coil diameters. However, the larger the diameter of coil, the higher the heat extraction per meter length of soil. The specific heat extraction also increased, but the heat extraction per meter length of soil decreased with the increase of coil central interval distance. 相似文献
996.
Warm temperature spikes represent one of the main spoilage causes of perishable good-stuffs. The development of packaging materials with thermal buffering properties represents a powerful solution to address the problems arising from an uncontrollable interruption during cold-chain logistic.Here, we propose the use of phase change material (PCM) composites for the design of cold storage packaging. Two different concentrations (25 and 50% w/w) of commercially available micro-encapsulated PCM were homogeneously dispersed in paper matrix via conventional negative filtration techniques. The possibility of obtaining composites with different latent heats in the 4-10 °C range has been demonstrated via differential scanning calorimetry measurements. Heat transmission tests, simulating the heating processes typical of the removal from a cold room, were performed on a suitable multilayer configuration. The obtained materials show the ability to maintain the inner temperature for a duration up to 10-fold longer in time, when compared to a similar cellulose material with a thickness of 2 cm. Experimental results have been numerically assessed by considering the material thermal parameters as homogeneous.Both experimental and computational approaches here discussed offer an easy way for the design of micro-encapsulated PCM-cellulose composite as building blocks in cold storage packaging design. 相似文献
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Gian Luigi Gragnani 《国际射频与微波计算机辅助工程杂志》2013,23(4):482-487
An analytical approach to inverse electromagnetic scattering is tested on 2‐D experimental data. The closed‐form singular value decomposition of the scattering integral operator is the basis for determining the radiating components of the equivalent source density. This equivalent source is used to reconstruct the features of a scatterer. Reconstructions performed on different scattering data show the capabilities of the method and, thanks to the closed‐form solution, results are available after a very short time of computation. © 2013 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2013. 相似文献