169 research outputs found
Power Generation for Wearable Electronics: Designing Electrochemical Storage on Fabrics
We report a new class of textiles with electrochemical functions which, when moistened by a conductive liquid (saline solution, sweat, wound fluid, etc.), generate DC voltage and current levels capable of powering wearable electronics on the go. Contrary to previously reported power generation techniques, the proposed fabrics are fully flexible, feel and behave like regular clothing, do not include any rigid components, and provide DC power via moistening by readily available liquids. Our approach is inspired by the commercially available Procellera® wound dressing, and entails printed battery cells that are composed of silver and zinc electrodes deposited onto a fabric to generate power in the microwatt range. Proof-of-concept results using the Procellera® dressing show feasibility and reproducibility. Scalable DC power may also be achieved by connecting multiple battery cells in series via flexible and conductive E-threads. Indeed, a series connection of two Procellera® dressings was demonstrated to boost the generated voltage from 0.9 V to 1.2 V. Notably, this in-series printed battery arrangement was further shown to successfully power a digital thermometer using 0.5 M NaCl solution (mimicking human sweat) as the electrolyte. Furthermore, customized fabric creation, which optimizes the Procellera® dressing for power generation, is discussed. Overall, the proposed technology is expected to be of utmost significance for healthcare, sports, military, and consumer applications, among others.A one-year embargo was granted for this item.Academic Major: Electrical and Computer Engineerin
A new way of valorizing biomaterials: the use of sunflower protein for 1 a-tocopherol microencapsulation
Biopolymer based microparticles were efficiently prepared from sunflower protein (SP) wall material and a-tocopherol (T) active core using a spray-drying technique. Protein enzymatic hydrolysis and/or N-acylation were carried out to make some structural modifications to the vegetable protein. Native and hydrolyzed SP were characterized by Asymmetrical Flow Field-Flow Fractionation (AsFlFFF). Results of AsFlFFF confirmed that size of proteinic macromolecules was influenced by degree of hydrolysis. The effect of protein modifications and the influence of wall/core ratio on both emulsions and microparticle properties were evaluated. Concerning emulsion properties, enzymatic hydrolysis involved a decrease in viscosity, whereas acylation did not significantly affect emulsion droplet size and viscosity. Microparticles obtained with hydrolyzed SP wall material showed lower retention efficiency (RE) than native SP microparticles (62-80% and 93% respectively). Conversely, acylation of both hydrolyzed SP and native SP allowed a higher RE to be reached (up to 100%). Increasing T concentration increased emulsion viscosity, emulsion droplet size, microparticle size, and enhanced RE. These results demonstrated the feasibility of high loaded (up to 79.2% T) microparticles
Manipulation of focal patterns in acoustic Soret type zone plate lens by using reference radius/phase effect
[EN] The manipulation of focal patterns of acoustic underwater Soret Zone Plate lens in far fields, such as manipulation (optimization) of Sidelobe Level and the design of long depth of focus by selecting the simple free parameter called reference radius (phase) has been demonstrated. Two effects have been studied by means of numerical simulations. Regarding the first effect, simulations demonstrate diffraction limited focal spot (0.47 wavelength) and 3 dB reduction of the first Side Lobe Level using Soret ZP with an optimal reference radius and without causing neither main lobe broadening or gain reduction. In the second effect, by using numerical simulations an increasing of depth of focus, more than 2 times, in comparison with classical Soret ZP with high numerical aperture (F/D=2.5), was observed.This work has been supported by TEC2015-70939-R (MINECO/FEDER).Tarrazó-Serrano, D.; Rubio Michavila, C.; Minin, OV.; Candelas Valiente, P.; Minin, IV. (2019). Manipulation of focal patterns in acoustic Soret type zone plate lens by using reference radius/phase effect. Ultrasonics. 91:237-241. doi:10.1016/j.ultras.2018.07.022S2372419
Optimised protein recovery from mackerel whole fish by using sequential acid/alkaline isoelectric solubilization precipitation (ISP) extraction assisted by ultrasound
peer-reviewedThe growing fishery industry needs to find new green-processes in order to provide a solution to the huge amount of wastes and by-products that such industrial activity produces. Currently, around a 40% of the total weight of the mackerel is considered a by-product, because just the fillets are used in the food market. ISP method has been revealed as a useful tool for protein recovering, however the yield of this process is traditionally lower than enzymatic methods. In present work, the use of sequential acid/alkaline extraction and alkaline extraction assisted by ultrasound, have been implemented in order to increase the yield of the process. It has been demonstrated that (i) sequential extraction is able to recover practically 100% of total protein, and (ii) applying ultrasound to alkaline extraction is possible to recover more than 95% of total protein from mackerel by-products. Extracted proteins were characterized according to their size, and the amino acid profile of final product was determined.This project (Grant-Aid Agreement No. MFFRI/07/01) was carried out under the Sea Change Strategy with the support of the Marine Institute and the Department of Agriculture, Food and the Marine, funded under the National Development Plan 2007–2013
Optimization of conventional and ultrasound assisted extraction of flavonoids from grapefruit (Citrus paradisi L.) solid wastes
Flavonoid compounds from grapefruit wastes were obtained by conventional solid liquid extraction (CE) and ultrasound assisted extraction (USE). Naringin was by far the most abundant flavonoid in the extracts ranging from 18 to 28 mg/g dw for CE and 24-36 mg/g dw for USE. Response surface methodology allowed obtaining predictive models for total phenolic content (TPC) and total antioxidant activity (TAA) as a function of the process variables ethanol concentration (Etc) (defined as weight of ethanol/weight of solution), temperature (T) and time (t) with reasonable success (CE-TPC, R-2 = 0.86, CE-TAA, R-2 = 0.85; USE-TPC, R-2 = 0.82; USE, TAA, R-2 = 0.86). USE was very effective when compared with conventional solvent extraction, allowing higher extraction yields (on average TPC 50% and TAA 66% higher) with lower temperatures and extraction times. Although the optimum process conditions indicate the use of a low ethanol concentration and ultrasounds (T = 25 degrees C, EtC = 0.4 (g/g) (40 g/100 g) and t = 55 min leading to TPC = 80.0 mg GAE/g dw and TAA = 38.3 mmol trolox/g dw), it has been proved that an USE treatment free of organic solvent (EtC = 0 g/g), at moderate temperature (25 degrees C) and short time (t = 3 min) leads to similar results (TPC = 753 mg GAE/g dw and TAA = 31.9 mmol trolox/g dw), suggesting its use for economic and environmental purposes.The authors acknowledge the Universitat Politecnica de Valencia (Spain) for its financial support through the project 1965 (PAID05-11).Garcia-Castello, EM.; Rodríguez López, AD.; Mayor López, L.; Ballesteros, R.; Conidi, C.; Cassano, A. (2015). Optimization of conventional and ultrasound assisted extraction of flavonoids from grapefruit (Citrus paradisi L.) solid wastes. Food Science and Technology. 64(2):1114-1122. https://doi.org/10.1016/j.lwt.2015.07.024S1114112264
Low-Temperature drying of salted cod (Gadus morhua) assisted by high power ultrasound: Kinetics and physical properties
[EN] Low-temperature convective drying could be considered an affordable alternative to conventional freeze-drying
for foodstuffs. The process intensification should be based on non-thermal technologies, such as power ultrasound.
Thereby, the aim of this work was to evaluate the air-borne application of power ultrasound on the
low-temperature drying of salted cod. For that purpose, drying experiments were carried out at −10, 0, 10
and 20 °C on salted cod slices at 2 m/s with (AIR + US, 20.5 kW/m3) and without ultrasonic application (AIR).
In the dried-salted cod, its rehydration capacity was analyzed, as were the microstructural, textural and color
changes. At every temperature tested, ultrasound application increased the drying rate; thus, an average increase
of 74%was observed in the effective diffusivity. AIR+US dried samples were softer and exhibited a higher rehydration
capacity than AIR ones, which was linked to the microstructural changes produced by ultrasound. In
addition, color changes were induced by ultrasound application.
Industrial relevance: Nowadays, low-temperature convective drying represents a promising alternative for the
production of high-quality dried products. However, this technology is mostly limited by the low drying rate,
which retards the dehydration process and directly increases the processing costs. Power ultrasound, a nonthermal
technology, represents an interesting alternative means of improving low-temperature convective
drying due to the fact that acoustic (mechanical)waves may affectwater removal during dryingwith a low heating
capacity. Thereby, the ultrasonically enhanced low-temperature convective drying could constitute an affordable
alternative to lyophilization (or freeze-drying), which is mainly restricted to high-quality food commodities.The authors acknowledge the financial support both from the Ministerio de Economia y Competitividad (Ref. DPI2012-37466-C03-03) and Carmen Cambra S.L. for their technical support with the selection of the raw material. Cesar Ozuna was the recipient of a fellowship from the Universitat Politecnica de Valencia for his research stay in Aalesund University College.Ozuna López, C.; Cárcel Carrión, JA.; Walde, PM.; García Pérez, JV. (2014). Low-Temperature drying of salted cod (Gadus morhua) assisted by high power ultrasound: Kinetics and physical properties. Innovative Food Science and Emerging Technologies. 23:146-155. https://doi.org/10.1016/j.ifset.2014.03.008S1461552
Kinetic and Compositional Study of Phenolic Extraction from Olive Leaves (var.Serrana) by Using Power Ultrasound
[EN] Power ultrasound is being used as a novel technique for process intensification. In this study, the feasibility of using power ultrasound to improve the phenolic extraction from olive leaves was approached taking both compositional and kinetic issues into account and also determining the influence of the main process parameters (the electric power supplied, emitter surface and temperature). For this purpose, the extraction kinetics were monitored by measuring the total phenolic content and antioxidant capacity and mathematically described by Naik's model, and HPLC DAD/MS MS was used to identify and quantify the main polyphenols. The electric power supplied and the emitter surface greatly affected the effective ultrasonic power applied to the medium, and hence the extraction rate. However, the influence of temperature on ultrasound assisted extraction was not clear. Compared with conventional extraction, ultrasound assisted extraction reduced the
extraction time from 24 h to 15 min and did not modify the extract composition. Industrial relevance: Olive crop produces a significant quantity of byproducts (leaves, branches, solid and liquid wastes), coming from the tree pruning, fruit harvest and oil production, which are rich in phenolic compounds with bioactive properties. The extraction of the bioactive compounds could be an interesting option with which to increase the value of these byproducts, as it requires efficient extraction techniques in order to reduce processing costs and improve productivity. In this sense, ultrasound assisted extraction is considered a novel technique used as ameans of intensifying a slow process, such as the leaching of polyphenols fromvegetablematrices. In order to further address the industrial applications of ultrasound assisted extraction, a kinetic study should be carried out determining both the effective energy introduced into the medium, as well as its influence on the extract quality.The authors thank the Generalitat Valenciana (PROMETEO/2010/062 and PROMETEO/2012/007) for its financial support. M. H. Ahmad Qasem was the recipient of a fellowship from Ministerio de Educacion, Cultura y Deporte of Spain (Programa de Formacion de Profesorado Universitario del Programa Nacional de Formacion de Recursos Humanos de Investigacion).Ahmad-Qasem Mateo, MH.; Canovas, J.; Barrajon-Catalan, E.; Micol, V.; Cárcel Carrión, JA.; García Pérez, JV. (2013). Kinetic and Compositional Study of Phenolic Extraction from Olive Leaves (var.Serrana) by Using Power Ultrasound. Innovative Food Science and Emerging Technologies. (17):120-129. https://doi.org/10.1016/j.ifset.2012.11.008S1201291
Food industry by-products valorization and new ingredients: cases of study
The concern about food and beverages is gaining importance for the general public in terms of health and more environmentally sustainable food products. Healthy foods imply the awareness on their safety, nutritional characteristics, and the potential inclusion of nutritive complements such as antioxidants, vitamins, and proteins, which promote a benefit to the consumer's health. Also, organic foods, with less added chemicals such as pesticides, are more demanded recently. The environmentally sustainable food production has to reconsider the wastes as by-products that can be transformed to provide valuable compounds (antioxidants, fiber, fuels, etc.) that could be used as new products or raw materials in the food industry or even applied in other sectors such as pharmaceutical, polymer, and energy industries. In this chapter, selected successful case studies in which food wastes are transformed into new products by using different separation and purification technologies will be shown. Furthermore, the use of different wild vegetables from natural environments as a source of valuable compounds and new ingredients will be described.info:eu-repo/semantics/publishedVersio
Optimization of total monomeric anthocyanin (TMA) and total phenolic content (TPC) extractions from mangosteen (Garcinia mangostana Linn.) hull using ultrasonic treatments.
The extraction yields of anthocyanins (TMA) and total phenolics (TPC) from mangosteen hull were optimized by varying the amplitude and time of ultrasonic treatment. The highest TMA recovery of 2.92 mg cy-3-glu/g hull powder was achieved using methanol aqueous solvent when direct ultrasonic treatment was applied for 15 min at 20% amplitude. For the TPC, 245.78 mg GAE/g hull powder was obtained in ethanol with sonication time of 25 min and at 80% amplitude. These TMA and TPC yields obtained are respectively 45.6% and 8.8% higher (p < 0.05) when compared to those without ultrasonic treatment. The ultrasonic treatment is able to improve anthocyanin extraction more effectively than the total phenolics from mangosteen hull
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