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51.
Daniele de Almeida Paula Eduardo Basílio de Oliveira Alvaro Vianna Novaes de Carvalho Teixeira Ariana de Souza Soares Afonso Mota Ramos 《International Journal of Food Science & Technology》2018,53(2):475-483
This study addressed the correlation between physical characteristics of double emulsions and sensory perception, as the microstructure of these systems may provide the mechanism to understanding the initial cause of the altered salty taste. Thus, double emulsions (W/O/W) were prepared using different volumes of the internal aqueous phase while maintaining the same fat and sodium contents in the evaluated systems. Polyglycerol polyricinoleate (PGPR) and tween 80 were used as hydrophobic and hydrophilic emulsifiers, respectively. After preparation, the samples were stored at 25 °C for 4 days and submitted to analysis of optical microscopy, distribution and polydispersity of the oil droplets size, electrical conductivity, rheological behaviour and sensorial analysis. It was found that the use of different emulsifier concentrations (PGPR) did not influence the physical characteristics of the emulsions with the same formulation, but emulsions with different internal aqueous phase concentrations presented different results. These distinct characteristics may have influenced sensorial perception, as the emulsion with higher internal phase concentration was considered saltier. Thus, it can be concluded that structural differences of the double emulsions can be used to decrease the sodium contents without perceivable changes in salty taste. 相似文献
52.
Shayan Seyedin Simge Uzun Ariana Levitt Babak Anasori Genevieve Dion Yury Gogotsi Joselito M. Razal 《Advanced functional materials》2020,30(12)
The integration of nanomaterials with high conductivity into stretchable polymer fibers can achieve novel functionalities such as sensing physical deformations. With a metallic conductivity that exceeds other solution‐processed nanomaterials, 2D titanium carbide MXene is an attractive material to produce conducting and stretchable fibers. Here, a scalable wet‐spinning technique is used to produce Ti3C2Tx MXene/polyurethane (PU) composite fibers that show both conductivity and high stretchability. The conductivity at a very low percolation threshold of ≈1 wt% is demonstrated, which is lower than the previously reported values for MXene‐based polymer composites. When used as a strain sensor, the MXene/PU composite fibers show a high gauge factor of ≈12900 (≈238 at 50% strain) and a large sensing strain of ≈152%. The cyclic strain sensing performance is further improved by producing fibers with MXene/PU sheath and pure PU core using a coaxial wet‐spinning process. Using a commercial‐scale knitting machine, MXene/PU fibers are knitted into a one‐piece elbow sleeve, which can track various movements of the wearer's elbow. This study establishes fundamental insights into the behavior of MXene in elastomeric composites and presents strategies to achieve MXene‐based fibers and textiles with strain sensing properties suitable for applications in health, sports, and entertainment. 相似文献
53.
de Mello Innocentini Murilo Daniel Lovero Federico Giovanni Ferreira Ariana Silva Das Tapas K. Tronville Paolo 《Clean Technologies and Environmental Policy》2021,23(8):2319-2335
Clean Technologies and Environmental Policy - For decades, wet scrubbers have been used to control particulate matter (PM) emitted by bagasse-fired boilers in the sugarcane industry. This choice... 相似文献
54.
Lars Chr. Christensen Tore R. Christiansen Yan Jin John Kunz & Raymond E. Levitt 《Computer-Aided Civil and Infrastructure Engineering》1997,12(3):157-170
In this paper we describe an object–oriented framework for developing enterprise models of Architecture, Engineering, Construction projects, and a methodology for formalizing these models such that they can be used for discrete event simulation of information processing and coordination in project execution. The simulation results can be used to predict the probable effects of carrying out proposed changes in planning and managing projects.
In our enterprise modeling framework we represent engineering design projects in terms of deliverables (requirements and solutions), plans (activities and process relations), and organization (participants and organizational relations). The resulting project model is the starting point for identifying coordination requirements between project team participants. Our methodology uses matrix techniques derived from qualtiy function deployment (QFD) to identify interactions between project requirements and solutions and calculate measures of product complexity . We then describe information flow between project activities in a similar matrix and calculate measures of process uncertainty . Finally, we identify the responsibilities of project team members and use a matrix to point out organizational interdependencies .
We apply our framework and methodology to model and simulate engineering design for a major extension of an electrical power substation. Our simulation results demonstrate how project performance is contingent on the fit between the project policies and the objectives and preferences of the project team. 相似文献
In our enterprise modeling framework we represent engineering design projects in terms of deliverables (requirements and solutions), plans (activities and process relations), and organization (participants and organizational relations). The resulting project model is the starting point for identifying coordination requirements between project team participants. Our methodology uses matrix techniques derived from qualtiy function deployment (QFD) to identify interactions between project requirements and solutions and calculate measures of product complexity . We then describe information flow between project activities in a similar matrix and calculate measures of process uncertainty . Finally, we identify the responsibilities of project team members and use a matrix to point out organizational interdependencies .
We apply our framework and methodology to model and simulate engineering design for a major extension of an electrical power substation. Our simulation results demonstrate how project performance is contingent on the fit between the project policies and the objectives and preferences of the project team. 相似文献
55.
Heterogeneous reactions of methylglyoxal in acidic media: implications for secondary organic aerosol formation 总被引:1,自引:0,他引:1
Recent environmental chamber studies have suggested that acid-catalyzed particle-phase reactions of organic carbonyls contribute to the formation of secondary organic aerosol (SOA). We report the first measurements of uptake of methylglyoxal on liquid H2SO4 over the temperature range of 250-298 K and acidic range of 55-85 wt %. From the time-dependent uptake the effective Henry's law solubility constant (H*) was determined. Heterogeneous reactions of methylglyoxal are shown to decrease with acidity and involve negligible formation of sulfate esters. Hydration and polymerization likely explain the measured uptake of methylglyoxal on H2SO4 and the measurements do not support an acid-catalyzed uptake of methylglyoxal. The results imply that heterogeneous reactions of methylglyoxal contribute to organic aerosol formation in less acidic media and hydration and polymerization of methylglyoxal in the atmospheric aerosol-phase are dependent on the hygroscopicity, rather than the acidity of the aerosols. 相似文献
56.
Haiyan Cen Renfu Lu Diwan P. Ariana Fernando Mendoza 《Food and Bioprocess Technology》2014,7(6):1689-1700
Hyperspectral imaging is useful for detecting internal defects of pickling cucumbers. The technique, however, is not yet suitable for high-speed online implementation due to the challenges in analyzing large-scale hyperspectral images. This research aimed to select the optimal wavebands from the hyperspectral image data, so that they can be deployed in either a hyperspectral or multispectral imaging-based inspection system for the automatic detection of internal defects of pickling cucumbers. Hyperspectral reflectance (400–700 nm) and transmittance (700–1,000 nm) images were acquired, using an in-house developed hyperspectral imaging system running at two conveyor speeds of 85 and 165 mm/s, for 300 “Journey” pickling cucumbers before and after internal damage was induced by mechanical load. Minimum redundancy–maximum relevance (MRMR) was used for optimal wavebands selection, and the loadings of principal component analysis (PCA) were also applied for qualitatively identifying the important wavebands that are related to the specific features. Discriminant analysis with Mahalanobis distance classifier was performed for the two-class (i.e., normal and defective) and three-class (i.e., normal, slightly defective, and severely defective) classifications using the mean spectra and textural features (energy and variance) from the regions of interest in the spectral images at selected waveband ratios. The classification results based on MRMR wavebands selection were generally better than those from PCA-based classifications. The two-band ratio of 887/837 nm from MRMR gave the best overall classification results, with the accuracy of 95.1 and 94.2 % at the conveyor speeds of 85 and 165 mm/s, respectively, for the two-class classification. The highest classification accuracies for the three-class classification based on the optimal two-band ratio of 887/837 nm were 82.8 and 81.3 % at the conveyor speeds of 85 and 165 mm/s, respectively. The mean spectra-based classification achieved better results than the textural feature-based classification, except in the three-class classification for the higher conveyor speed. The overall classification accuracies for all selected waveband ratios at the low conveyor speed were slightly higher than those at the higher conveyor speed, since the low speed resulted in more scan lines, thus higher spatial resolution hyperspectral images. The identified two-band ratio of 887/837 nm in transmittance mode could be applied for fast real-time internal defect detection of pickling cucumbers. 相似文献
57.
Nutrition support programs that only focus upon better complementary feeding remain an insufficient means of limiting growth
faltering in vulnerable populations of children. To determine if symptoms of acute infections correlate with the incidence
of growth faltering in rural Malawian children, the associations between fever, diarrhea, and cough with anthropometric measures
of stunting, wasting, and underweight were investigated. Data were analyzed from a trial where 209 children were provided
with adequate complementary food and followed fortnightly from 6-18 months of age. Linear mixed model analysis was used to
test for associations. Diarrheal disease was inversely associated with changes in height-for-age Z-score (HAZ), mid-upper
arm circumference Z-score (MUACZ), and weight-for-age Z-score (WAZ). Fever was also inversely associated with changes in MUACZ
and WAZ. These results suggest that initiatives to reduce febrile and diarrheal diseases are needed in conjunction with improved
complementary feeding to limit growth faltering in rural Malawi. 相似文献
58.
Ana Beatriz Lopes de Sousa Jabbour Fernanda de Souza Azevedo Ariana Fernandes Arantes Charbel José Chiappetta Jabbour 《The International Journal of Advanced Manufacturing Technology》2013,68(1-4):807-815
The objective of this article is to analyse how green supply chain management (GSCM) practices are being adopted by some high-tech companies located in Brazil. The research was conducted using the case study approach, focusing on eight companies that are representative of this sector. The main results are: (a) the most adopted GSCM practices in the studied high-tech companies located in Brazil are internal environmental management, investment recovery and reverse logistics and (b) Brazilian environmental legislation and international policies are very important in driving the adoption of GSCM practices. The internationalisation of companies was also found to be a variable that interferes with the adoption of GSCM practices. This is one of the first studies that examine the relationship between GSCM and the internationalisation of companies located in Brazil. 相似文献
59.
Ariana Allen Rupalatha Maddala Camelia Eldawy Ponugoti Vasantha Rao 《International journal of molecular sciences》2022,23(9)
The cytoarchitecture and tensile characteristics of ocular lenses play a crucial role in maintaining their transparency and deformability, respectively, which are properties required for the light focusing function of ocular lens. Calcium-dependent myosin-II-regulated contractile characteristics and mechanosensitive ion channel activities are presumed to influence lens shape change and clarity. Here, we investigated the effects of load-induced force and the activity of Piezo channels on mouse lens myosin II activity. Expression of the Piezo1 channel was evident in the mouse lens based on immunoblot and immufluorescence analyses and with the use of a Piezo1-tdT transgenic mouse model. Under ex vivo conditions, change in lens shape induced by the load decreased myosin light chain (MLC) phosphorylation. While the activation of Piezo1 by Yoda1 for one hour led to an increase in the levels of phosphorylated MLC, Yoda1 treatment for an extended period led to opacification in association with increased calpain activity and degradation of membrane proteins in ex vivo mouse lenses. In contrast, inhibition of Piezo1 by GsMTx4 decreased MLC phosphorylation but did not affect the lens tensile properties. This exploratory study reveals a role for the mechanical load and Piezo1 channel activity in the regulation of myosin II activity in lens, which could be relevant to lens shape change during accommodation. 相似文献
60.
Richard L Davies D Robin Baigent Malcolm S Levitt Yasin Mollah Carl J Rayner Alison B Frensham 《Journal of the science of food and agriculture》1992,59(4):423-436
Five laboratories collaborated in a two-part study to improve and measure the accuracy and precision of amino acid analysis. The results of the unpublished first part allowed each laboratory the opportunity to optimise their own procedure. In the second part of the study reported here, three purified and six conventional proteins were analysed, each after three different preparation procedures (normal and extended acid hydrolysis, and following preliminary oxidation). Preparative effects reported in the literature were confirmed though not uniformly, and there were other, often unique, preparative effects. Well documented preparative effects are essential in matching analytical work to differing requirements. Results from one laboratory were excluded from further statistical analysis because of high replicate variation. The repeatability (within laboratory) coefficient of variation was 4.1% and for reproducibility (between laboratory) it was 13.1%. Discrepancies between best amino acid estimates for purified proteins and estimates calculated from published sequences (P < 0.01) provided evidence of bias in five amino acids from one laboratory and in one from another. When P < 0.01 was used as the discard threshold for conventional protein results, a total of 9.9% of best estimates were discarded: 8.1% were biased, 3.2% were outliers and 1.3% were both biased and outliers. When these values were discarded, 19 of 96 mean values changed by up to 4%, nine changed by 4-8%, eight changed by larger amounts and the pooled coefficient of variation fell from 8.2% to 5.4%. At this threshold between zero and 31% of each laboratory's data on conventional proteins was discarded. A lower threshold (P < 0.05) doubled the discard rate but had marginal effects on mean values and residual variation. At P < 0.01 less than 20% of biased estimates were also outliers and less than half the outliers were also biased. This means that only studies which examine both accuracy and precision will achieve maximum improvement in either. 相似文献