6,971 research outputs found
Recent development in kinetic theory of granular materials: analysis and numerical methods
33 pagesOver the past decades, kinetic description of granular materials has received a lot of attention in mathematical community and applied fields such as physics and engineering. This article aims to review recent mathematical results in kinetic granular materials, especially for those which arose since the last review by Villani on the same subject. We will discuss both theoretical and numerical developments. We will finally showcase some important open problems and conjectures by means of numerical experiments based on spectral methods
Robust Design of Artificial Neural Networks Methodology in Neutron Spectrometry
Applications of artificial neural networks (ANNs) have been reported in literature in various
areas. [1â5] The wide use of ANNs is due to their robustness, fault tolerant and the ability
to learn and generalize, through training process, from examples, complex nonlinear and
multi input/output relationships between process parameters using the process data. [6â10]
The ANNs have many other advantageous characteristics, which include: generalization,
adaptation, universal function approximation, parallel data processing, robustness, etc.
Multilayer perceptron (MLP) trained with backpropagation (BP) algorithm is the most used
ANN in modeling, optimization classification and prediction processes. [11, 12] Although
BP algorithm has proved to be efficient, its convergence tends to be very slow, and there is a
possibility to get trapped in some undesired local minimum. [4, 10, 11, 13]
Most literature related to ANNs focused on specific applications and their results rather
than the methodology of developing and training the networks. In general, the quality
of the developed ANN is highly dependable not only on ANN training algorithm and its
parameters but also on many ANN architectural parameters such as the number of hidden
layers and nodes per layer which have to be set during training process and these settings
are very crucial to the accuracy of ANN model. [8, 14â19
In Vitro Antioxidant Activity Optimization of Nut Shell (Carya Illinoinensis) by Extrusion Using Response Surface Methods
The pecan (Carya illinoinensis) nut shell is an important byproduct of the food processing industry that has not been previously explored as an antioxidant compound. This work aims to study the effect of the extrusion temperature and screw speed on the moisture content, water and oil absorption index, water solubility index, color, phenolic compounds, condensed tannin compounds, and antioxidant activity of pecan nut shell extrudates. Extrusion variables were adjusted using a response surface methodology. Extrusion, performed at 70 °C and 150 rpm, almost doubled the concentration of polyphenols in the non-extruded shell and significantly increased radical scavenging activity. Compounds in extrudates, performed at 70 °C and 150 rpm, were quantified by high-performance liquid chromatography (HPLC) with a diode-array detector (DAD) and identified by liquid chromatography coupled with time-of-flight mass spectrometry (LC-MSD-TOF). Extrusion significantly increased most phenolic acid compounds, including gallic acid, ellagic acid pentose, ellagic acid, dimethyl ellagic acid rhamnoside, and dimethyl ellagic acid. The soluble fiber in extrudates was more than three-fold higher than in the control. Therefore, extrusion at 70 °C and 150 rpm increased the concentration of phenolic compounds, antioxidant activity, and total dietary and soluble fiber. Our findings support the notion that extruded pecan nut shell can be used in clean-label products and improve their nutraceutical value
Recent development in kinetic theory of granular materials: analysis and numerical methods
33 pagesOver the past decades, kinetic description of granular materials has received a lot of attention in mathematical community and applied fields such as physics and engineering. This article aims to review recent mathematical results in kinetic granular materials, especially for those which arose since the last review by Villani on the same subject. We will discuss both theoretical and numerical developments. We will finally showcase some important open problems and conjectures by means of numerical experiments based on spectral methods
Exploiting the CH-Ï interactions in supramolecular hydrogels of aromatic carbohydrate amphiphiles
A novel class of supramolecular hydrogels derived from amino sugars is reported, where the self-assembly of aromatic carbohydrate amphiphiles is driven by CH-Ï interactions, rather than ÏâÏ stacking and H-bonding associated with gelators based on aromatic peptide amphiphiles. Spectroscopic data is provided as evidence for this mode of self-assembly and in silico studies revealed that a combination of CH-Ï and T-stacking of the fluorenyl groups contribute to the formation of the aggregated structures
Evaluation of non-extruded and extruded pecan (Carya illinoinensis) shell powder as functional ingredient in bread and wheat tortilla
Pecan shell is a source of dietary fiber and phytochemicals, both necessary in the human diet. Therefore, pecan shell powder could be used as a supplement in the preparation of food products. The present study evaluated the effect of addition of 5, 10 and 15% (w/w) pecan shell powder, non-extruded (PSN) or extruded (PSE), in the physical properties of bread and wheat tortillas. Breads and tortillas produced with the higher substitution level that did not detriment significantly their physical properties (5% in breads and 10% in tortillas) were characterized in terms of chemical composition, total phenolic content (TPC), radical scavenging activity (RSA) and in vitro viability of human-derived liver cancer cells. Breads and tortillas produced with PSE (5% and 10%, respectively) presented the highest total dietary fiber content, TPC and RSA. In addition, extracts obtained from these same treatments, reduced the viability of hepatic cancer cells up to 53%. Sensory analysis of breads and tortillas supplemented with PSN or PSE showed adequate overall acceptability by consumers. Results obtained in the present study support that the pecan shell powder can be used as functional ingredient in bakery products especially when pretreated by extrusion
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