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491.
W. D. Duncan R. E. Schwall K. D. Irwin J. A. Beall C. D. Reintsema William Doriese Hsiao-Mei Cho Brian Estey Goutam Chattopadhyay Peter Ade Carole Tucker 《Journal of Low Temperature Physics》2008,151(3-4):777-783
We present the outline of the optical design of a TeraHertz (THz) imager for the detection of shrapnel-loaded improvised explosive
devices (IED) devices at “stand-off” distances of 14–26 meters. The system will use 4 antenna-coupled TES detector arrays
of 16 by 16 pixels cooled in a cryogen-free system with microwave readout to see beneath clothing at non-lethal detonation
distances. A spatial resolution of ∼10 mm and close to video frame rates is anticipated.
相似文献
492.
Sébastien Patoux Lucas Sannier Hélène Lignier Yvan Reynier Carole Bourbon Séverine Jouanneau Frédéric Le Cras Sébastien Martinet 《Electrochimica acta》2008,53(12):4137-4145
High voltage spinel oxides with composition LiMn2 − xMxO4 (M, a transition metal element) have remarkable properties such as high potential, high energy density and high rate capability. We believe that these positive electrode materials could replace the widespread commercial layered nickel cobalt oxides in some applications. The present assessment highlights electrochemical performance of optimized LiNi0.5Mn1.5O4 and substituted counterparts, all having a spinel structure (cubic close-packed oxygen array) similar to the relative LiMn2O4. To fully emphasize the benefit from high potential spinel oxides, tests have been performed versus lithium metal, Li4Ti5O12 and graphite, using various electrode loadings (0.3-4.5 mAh cm−2) and cycling rates (from C/20 to 60C rate). Steady capacity retention (130-140 mAh g−1 for nearly 500 cycles) and flat voltage (4.7 V vs. Li+/Li) have been obtained at C/5 rate at room temperature. Effect of cycling at high temperature has been shown to be less critical than for LiMn2O4. High voltage spinel oxides still sustain 100 mAh g−1 and over after 400 cycles at 55 °C at 1C rate. Rate capability is also excellent, with only 4% loss of capacity when comparing C/8 and 8C rates (thin electrodes). 相似文献
493.
Arnaud Hallier Sylvie Chevallier Thierry Serot Carole Prost 《Journal of the science of food and agriculture》2007,87(5):814-823
The colour of raw fillets and the texture of cooked fillets of European catfish (Silurus glanis) were studied. The catfish fillets resulted from two types of farming conditions used in France. Sensory and instrumental analyses were performed on the fillets. Two farming parameters were found to affect the colour and texture of European catfish fillets: water temperature and farming time. The shorter the farming time was, the lighter the fillets were, while a higher water temperature produced yellower and greener fillets. A higher water temperature and a longer farming time produced softer cooked fillets, while the higher the water temperature was, the less juicy the cooked fillets were. A good correlation and complementarity were observed between sensory and instrumental analyses of the colour and texture of European catfish fillets. Copyright © 2007 Society of Chemical Industry 相似文献
494.
Carole Tournier Manon Grass Dhananjay Zope Christian Salles Dominique Bertrand 《Journal of food engineering》2012
The methods currently used to characterise food breakdown during mastication are not easily applicable to cohesive and heterogeneous products such as white bread (baguettes). During this study, we investigated the applicability of image texture analysis to characterising the kinetics of bread bolus formation during chewing. Food boluses were collected from five subjects chewing four different breads after 10, 20 and 30 chewing cycles or at swallowing. Images were acquired and analysed using the Grey level co-occurrence matrix (GLCM) method. Food boluses were successfully discriminated: 60–73% of the images were correctly classified into their respective chewing cycles. Incorrect classifications arose from overlapping between subsequent cycles. Among the texture features the contrast was identified as being the best marker of food degradation. Different kinetics of bolus formation were observed between breads. This method revealed specific patterns of food degradation between subjects, which could be explained by their mastication behaviour and chewing efficiency. 相似文献
495.
Gerardo Benito Rick Rohde Mary Seely Christoph Külls Ofer Dahan Yehouda Enzel Simon Todd Blanca Botero Efrat Morin Tamir Grodek Carole Roberts 《Water Resources Management》2010,24(4):641-667
This paper summarises innovative research into the assessment of long-term groundwater recharge from flood events in dryland environments of the Kuiseb (Namibia) and the Buffels (South Africa) rivers. The integrated water resource management (IWRM) policies and institutions affecting the exploitation of groundwater resources in each of these developing countries are compared. The relatively large alluvial aquifer of the Kuiseb River (~240 Mm3) is recharged from irregular floods originating in the upper catchment. Reported abstraction of 4.6 Mm3 per year is primarily consumed in the town of Walvis Bay, although the groundwater decay (pumping and natural losses along the period 1983–2005) was estimated in 14.8 Mm3 per year. Recharge is variable, occurring in 11 out of 13 years in the middle Kuiseb River, but only in 11 out of 28 years in the middle-lower reaches. In contrast, the Buffels River has relatively minor alluvial aquifers (~11 Mm3) and recharge sources derive from both lateral subsurface flow and floodwater infiltration, the latter limited to a recharge maximum of 1.3 Mm3 during floods occurring once every four years. Current abstractions to supply the adjacent rural population and a few small-scale, irrigated commercial farms are 0.15 Mm3 yr???1, well within the long-term sustainable yield estimated to be 0.7 Mm3 yr???1. Since independence in 1990, Namibia’s water resource management approach has focussed on ephemeral river basin management of which the Kuiseb Basin Management Committee (KBMC) is a model. Here, some water points are managed independently by rural communities through committees while the national bulk water supplier provides for Walvis Bay Municipality from the lower aquifers. This provides a sense of local ownership through local participation between government, NGOs and CBOs (community-based organisations) in the planning and implementation of IWRM. Despite the potential for water resource development in the lower Buffels River, the scope for implementing IWRM is limited not only by the small aquifer size, but also because basin management in South Africa is considered only in the context of perennial rivers. Since 2001, water service delivery in the Buffels River catchment has become the responsibility of two newly created local municipalities. As municipal government gains experience, skills and capacity, its ability to respond to local needs related to water service delivery will be accomplished through local participation in the design and implementation of annual ‘integrated development plans’. These two case studies demonstrate that a variety of IWRM strategies in the drylands of developing countries are appropriate depending on scales of governance, evolving policy frameworks, scales of need and limitations inherent in the hydrological processes of groundwater resources. 相似文献
496.
Fabrice Séverac Pierre Alphonse Alain Estève Aurélien Bancaud Carole Rossi 《Advanced functional materials》2012,22(2):323-329
Over the next few years, it is expected that new, energetic, multifunctional materials will be engineered. There is a need for new methods to assemble such materials from manufactured nanopowders. In this article, we demonstrate a DNA‐directed assembly procedure to produce highly energetic nanocomposites by assembling Al and CuO nanoparticles into micrometer‐sized particles of an Al/CuO nanocomposite, which has exquisite energetic performance in comparison with its physically mixed Al/CuO counterparts. Using 80 nm Al nanoparticles, the heat of reaction and the onset temperature are 1.8 kJ g?1 and 410 °C, respectively. This experimental achievement relies on the development of simple and reliable protocols to disperse and sort metallic and metal oxide nanopowders in aqueous solution and the establishment of specific DNA surface‐modification processes for Al and CuO nanoparticles. Overall, our work, which shows that DNA can be used as a structural material to assemble Al/Al, CuO/CuO and Al/CuO composite materials, opens a route for molecular engineering of the material on the nanoscale. 相似文献
497.
In this paper, we investigate a new method to enforce topology preservation on deformation fields. The method is composed of two steps. The first one consists in correcting the gradient vector fields of the deformation at the discrete level, in order to fulfill a set of conditions ensuring topology preservation in the continuous domain after bilinear interpolation. This part, although related to prior works by Kara?ali and Davatzikos, proposes a new approach based on interval analysis. The second one aims to reconstruct the deformation, given its full set of discrete gradient vectors. The problem is phrased as a functional minimization problem on the convex subset K of the Hilbert space V. The existence and uniqueness of the solution of the problem are established, and the use of Lagrange's multipliers allows to obtain the variational formulation of the problem on the Hilbert space V . Experimental results demonstrate the efficiency of the method. 相似文献
498.
Angélique Villière Gaëlle ArvisenetLaurent Lethuaut Carole ProstThierry Sérot 《Food chemistry》2012,131(4):1561-1568
The experimental conditions of a representative odour extraction method were determined after testing eight SPME, dynamic headspace and purge-and-trap procedures. Headspace SPME with a Car/PDMS fibre was evidenced to be the most suitable method to obtain representative extract of cider odour. This method was applied to extract the volatile compounds of two French ciders and gas chromatography-mass spectrometry-olfactometry (GC-MS-O) was used to analyse the odourant profile and the aroma-active compounds of these ciders. Thirty-six odourant zones were perceived in one cider and 24 in the other. Comprehensive two-dimensional gas chromatography combined with time-of-flight mass spectrometry was used to identify odour-active compounds which were undetermined after the first chromatographic separation. Ethyl 2-methylbutanoate, 2-phenylethanol, ethyl butanoate, ethyl 2-methylpropanoate, ethyl hexanoate, oct-1-en-3-one, 2-phenylethyl acetate, ethyl dodecanoate, 3-methyl-1-butanol and 2-methylbutanoic acid were among the most potent odourants in both ciders, as well as oct-1-en-3-one, which could be identified only by comprehensive GC. Thanks to the association of the two methods, 80% of the aroma-active compounds were identified, some of them being present at trace levels in ciders. 相似文献
499.
Esther Martínez-Martínez Paola Atzei Christine Vionnet Carole Roubaty Stephanie Kaeser-Pebernard Reto Naef Jrn Dengjel 《International journal of molecular sciences》2022,23(12)
Wound healing pathologies are an increasing problem in ageing societies. Chronic, non-healing wounds, which cause high morbidity and severely reduce the quality of life of affected individuals, are frequently observed in aged individuals and people suffering from diseases affected by the Western lifestyle, such as diabetes. Causal treatments that support proper wound healing are still scarce. Here, we performed expression proteomics to study the effects of the small molecule TOP-N53 on primary human skin fibroblasts and keratinocytes. TOP-N53 is a dual-acting nitric oxide donor and phosphodiesterase-5 inhibitor increasing cGMP levels to support proper wound healing. In contrast to keratinocytes, which did not exhibit global proteome alterations, TOP-N53 had profound effects on the proteome of skin fibroblasts. In fibroblasts, TOP-N53 activated the cytoprotective, lysosomal degradation pathway autophagy and induced the expression of the selective autophagy receptor p62/SQSTM1. Thus, activation of autophagy might in part be responsible for beneficial effects of TOP-N53. 相似文献
500.
Gas transfer properties of wheat gluten (WG) coated paper and their ability to fulfil the requirements in eMAP of fresh parsley were studied. Permeation of gases through WG-paper was demonstrated to be RH-dependent and closely related to structural modification in the WG layer. Formation of micro-cracks was evidenced in dry conditions; but when increasing RH, plasticisation occurs within the protein layer and micro-fractures were reduced until disappearance. This reversible phenomenon allowed the WG-layer to recover its integrity at RH higher than 70%, and the WG character to be expressed in such conditions. When used at 20 °C and 80% RH as part of the packaging of parsley, modified atmosphere was created and a steady state of 11 kPa O2 and 4.5 kPa CO2 was reached after 45 h. In such conditions, the overall quality of parsley leaves remained acceptable during 8 days, with only 28% loss of chlorophyll. 相似文献