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21.
Sanaz Behtaj  Said Sadri 《纺织学会志》2013,104(12):1094-1100
A novel objective yarn bulk measurement method has been developed through image analysis technique. Two orthogonal images are taken from the same part of a yarn and then transformed into gray scale. Each gray scale image is further processed separately by extracting the yarn image from background with the help of intensity histogram using adaptive threshold. This gives rise to a binary image which is used as input for the second part of the algorithm measuring yarn volume. The processing on the input image starts with omitting the long rare loops, considered as noise, by morphological operations. This is followed by measuring the width of the two orthogonal images pixel by pixel along the yarn. Finally, the total volume of the yarn is ascertained by integrating the volume of all the individual imaginary ovals with their two diameters replaced by the two widths of orthogonal images at the corresponding pixel.  相似文献   
22.
Date (Pheonix dactylifera L.) seeds are a valuable and abundant by‐product with various potential food applications. Free polyphenols (FPPs) and bound polyphenols (BPPs) of date seeds from Deglet Nour variety grown in Australia were investigated using high‐performance liquid chromatography‐mass spectrometry. The FPP fraction contained the following main phenolic compounds per gram of date seed powder; procyanidin B1 (499.8 ± 7.8 μg), procyanidin B2 (288.6 ± 6.1 μg), catechin (167.6 ± 2.1 μg), epicatechin (39.44 ± 0.39 μg), and protocatechuic acid (1.77 ± 0.22 μg). Additionally, one of the 2 A‐type dimers was confirmed as procyanidin A2 (24.05 ± 0.12 μg/g). A‐type dimers have not been reported before in date seeds. The BPP fraction contained epicatechin (52.59 ± 0.76 μg/g) and procyanidin B2 (294.2 ± 3.7 μg/g), while several peaks exhibiting ESI? m/z of 153 indicated dihydroxybenzoic acid isomers including protocatechuic acid (2.138 ± 0.025 μg/g). These findings contributed to our knowledge of date seed phytochemicals and understanding of their contribution to the reported bioactivities.  相似文献   
23.
Pulp and papermaking industries generate high volumes of carbohydrate-rich effluents. Microbial fuel cell (MFC) technology is based on organic materials’ consumption?and efficient power production. Using a classical two-chamber lab-scale MFC design with an external resistance of 2000 W, we investigated the effects of anode chamber biofilm adaptation (ACBA) and cathode chamber redox solutions (CCRS) on the operation efficiency of MFC when treating wastewater. In ACBA studies, biofilm growth activation showed an increase in the power density to 20.48, 35.18, and 36.98 mW/m2 when the acetate feeding concentrations were 3, 6, and 12 g/L, respectively. Improvement by biofilm adhesion on granular activated carbon (GAC) was examined by scanning electron microscopy (SEM). The obtained power density increased to 25.47, 33.42, and 40.39 mW/m2 when the GAC particles concentrations were 0, 50, and 100 g/L, respectively. The generated power densities were 51.26 and 40.39 mW/m2 as well as the obtained voltages were 0.41 and 0.72 V when the electrode area increased from 16 to 64 cm22, current density of 0.094 A/m2, and voltage of 1.20 V with a successful organic removal efficiency of 86.0% after 264 h of operation.  相似文献   
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Physicochemical (pH, brix, and color), sensory (color, taste, odor, mouthfeeling, consistency, bitter flavor, and general acceptability), and rheological properties of the hot chocolate beverages including different cocoa combinations were investigated in the present study. Cocoa type significantly affected all of the properties. Simple additive weighting approach was applied to obtain one score from seven different sensory parameters and simple additive weighting score was used in mixture design to determine optimum cocoa type or cocoa combination. Ostwald de Waele model described the flow behavior of the hot chocolate beverage samples with R2 values ranged between 0.818 and 0.999. The consistency coefficient (K) and apparent viscosity at shear rate 50 s?150) were significantly affected by cocoa type found in the formulation of the beverage. The mixture design approach was performed in order to determine variation of the responses (physicochemical, sensory, and rheological parameters) as a function of cocoa concentration. Simple additive weighting scores were satisfactorily described by established equation as a function of cocoa concentration to be used in the formulation of the hot chocolate beverage (R2 = 0.8645).  相似文献   
26.
In this study, the steady and dynamic rheological properties of the dairy dessert samples (puddings) containing carrageenan, alginate, guar and xanthan gums and their combinations were investigated in a model system, and mixture design was utilized to observe the effects of the gums and their interactions. The flow behaviour of the pudding samples fitted to the Ostwald de Waele model (R 2?>?0.98). All the samples exhibited a gel structure with their higher G′ (storage modulus) values than the G″ (loss modulus) values. Carrageenan was the most effective hydrocolloid on both the steady and dynamic rheological parameters of the dairy dessert samples. On the other hand, alginate had relatively smaller effect. Furthermore, 30 pudding samples containing different gum or gum combinations were classified into two groups (A and B) by using principal component analysis (PCA). Samples containing more than 33% carrageenan in their formulations made up the group A which positively correlated to K (consistency index), η 50 (apparent viscosity at shear rate 50 s?1), G′, G″, G* (complex modulus) and η* (complex viscosity) values.  相似文献   
27.
Enterocin AS-48 is a cyclic peptide of great interest for application in food preservation and sanitation. In the present study, the proteome response of Listeria monocytogenes to purified enterocin AS-48 was studied under two different conditions: planktonic cells and sessile cells grown on polystyrene plates. Ten different proteins were differentially expressed in planktonic L. monocytogenes cells treated with 0.1 μg/ml enterocin AS-48 compared to the untreated controls. Overexpressed proteins were related to stress response (DnaK) or carbohydrate transport and metabolism, while underexpressed and unexpressed proteins were related to metabolism (such as glyceraldehyde-3-phosphate dehydrogenase, pyruvate oxidase, glutamate dehydrogenase or glutamate decarboxylase) or stress (GroEL). In the sessile state, L. monocytogenes cells tolerated up to 10 μg/ml bacteriocin, and the treated biofilm cells overexpressed a set of 11 proteins, some of which could be related to stress response (DnaK, GroEL), protein synthesis and carbohydrate metabolism, while glyceraldehyde-3-phosphate dehydrogenase was the only unexpressed protein. Some of the overexpressed proteins (such as elongation factor Tu and GroEL) could also be implicated in cell adhesion. These results suggest different cell responses of L. monocytogenes to enterocin AS-48 in the planktonic and in the sessile state, including stress response and cell metabolism proteins. While in the planktonic state the bacterium may tend to compensate for the cytoplasmic cell permeability changes induced by AS-48 by reinforcing carbohydrate transport and metabolism, sessile cells seem to respond by shifting carbohydrate metabolism and reinforcing protein synthesis. Stress response proteins also seem to be important in the response to AS-48, but the stress response seems to be different in planktonic and in sessile cells.  相似文献   
28.
Chocolate compound was produced using ball mill refiner, and the effect of agitator shaft speed and refining time on the physical quality parameters (particle size, colour and steady‐state rheology) of compound chocolate was determined using response surface methodology. The shaft speed and refining time range were selected between 40–60 r.p.m. and 10–30 min, respectively. Determination coefficient of the models established for particle size, Newtonian viscosity and colour parameters (brightness, chroma and hue angle) were found to be very close to unity. Increasing shaft speed and time induced a reduction in particle size and an increase in viscosity of the samples. Temperature sweep test was also performed, and the obtained data were successfully fitted to Arrhenius equation to calculate the corresponding parameters representing temperature dependency of the compounds. The results highlighted that the establishment of such models can provide essential information in terms of optimisation of production processes regarding usage purpose of the compound chocolate.  相似文献   
29.
In this study, grape pomace (GP), a by-product consisting of grape skins and seeds rich in dietary fibres and polyphenols, was used in wafer sheets at different concentrations [5.00 (GP5), 10.0 (GP10), and 15.0 g 100 g−1 (GP15)] for the partial replacement of wheat flour (WF) and improve the functionality of wafer sheets. The GP inclusion at concentrations higher than 5.00 g 100 g−1 significantly affected the texture of sheets as well as the flow behaviour of batters, resulting in softer sheets and more viscous batters (P < 0.05). Moisture contents did not significantly change after GP addition (P > 0.05). After the addition of GP, the L* values decreased and the a* values increased, making the wafers darker (P < 0.05). Moreover, under simulated in vitro digestion conditions, the bioaccessibility of total phenolic compounds in saliva, gastric juice, and intestinal juice was significantly higher than control even at the lowest GP concentration (P < 0.05). Regarding sensory properties, only smoothness and crispness were significantly affected by GP addition, and samples were found to be crisper with higher concentrations of GP. In conclusion, it is possible to partially replace the WF in wafers with GP at a concentration of 5.00 g 100 g−1 to develop a product with higher functionality and nutrient content.  相似文献   
30.
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