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131.
Several approaches have been developed that use ensembles of air parcel back trajectories to identify likely source regions for contaminants observed at a downwind receptor site. Although the results of these models have appeared to provide results that agree with known sources, there have not been efforts to make direct comparisons between the results of such analyses with emissions inventories. In this paper, the results of residence time analysis (RTA) of data from Underhill, VT and from Brigantine, NJ are compared to the average estimated emissions of coal- and oil-fired power plants. Excellent correspondence was found between the areas of highest probability identified in the trajectory ensemble analyses and the averaged emission intensities. 相似文献
132.
Within the Convoy Model, social networks are viewed as dynamic hierarchic structures surrounding the individual throughout life. As a step toward empirical definition of convoy structure and function across the life span, a bicultural sample (N?=?159) of young adult women, their mothers, and their grandmothers were queried. Comparable results were obtained across generations and cultures with regard to network size, the amount of support provided by the network, and the nomination of close family members as primary sources of support. However, there was a marked shift across generations in the balance of familial vs friendship relations. Younger persons included fewer family members and more friends in their networks, and they received more support from friends. These cross-sectional results are consistent with the Convoy Model and suggest that longitudinal research is warranted. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
133.
The sulphur compounds composition of wines produced experimentally from six white cultivars (Alvarinho, Loureiro, Trajadura, Pedernã, Azal Branco and Avesso) was evaluated during two consecutive vintages. Results show that wines could be differentiated according to their sulphur compounds content. In general, Loureiro, Trajadura and Pedernã cultivars led to wines with low concentrations of sulphur compounds; however, Loureiro wines were characterised by significant amounts of dimethyl sulphone, whereas Trajadura wines possessed a high content of 3-(methylthio)propyl acetate and 4-(methylthio)-1-butanol. Alvarinho and Avesso wines showed high levels of S-methyl thioacetate, 3-mercapto-1-propanol, 3-(ethylthio)-1-propanol and 3-methylthiopropionic acid. Significant amounts of 2-methyltetrahydrothiophen-3-one, cis- and trans-2-methyltetrahydrothiophen-3-ol were also found in Avesso wines. Azal Branco wines were low in 3-(methylthio)propyl acetate and 2-(methylthio)ethanol, and high contents in S-methyl thioacetate, 3-mercapto-1-propanol and 2-mercaptoethanol. A linear discriminant analysis of sulphur compounds levels showed a differentiation of wines according to their varietal origin. 相似文献
134.
The wave concept iterative procedure (WCIP) is used to analyze a quasi‐square open metallic ring frequency selective surface (FSS). The quasi‐square open metallic ring FSS is dual‐polarized. When the incident plane wave is polarized in a direction parallel to the FSS’ coupled parallel strips, it shows two rejecting bands. Moreover, another rejecting band can be obtained if the source plane wave is perpendicularly polarized with respect to the FSS’ coupled parallel strips. The three resonant frequencies are inversely proportional to the length of the FSS’ coupled strips to provide an easy fine tuning of the FSS structure. The simulated results obtained using WCIP are compared to the measured results, and a good agreement is reported. 相似文献
135.
Carole Guillaume Isabelle Schwab Emmanuelle Gastaldi Nathalie Gontard 《Innovative Food Science and Emerging Technologies》2010,11(4):690-696
Freshness of common mushrooms was related to the internal atmosphere composition during modified atmosphere packaging (MAP) experiments at 20 °C and 80% RH with stretchable polyvinylchloride (PVC) film, paper, and the same paper coated with a wheat gluten solution. MAP with the stretchable film led to a detrimental deterioration of mushrooms after only one day of storage: dark brown blotches appeared and almost 30% of mushrooms exhibited open veil. This was due to the formation of condensed water at the inner surface of the material and onto mushrooms combined to a high O2 partial pressure (16 kPa) in the headspace. Wheat gluten (WG) coated paper was the most effective to improve the shelf-life of mushrooms since it allowed the preservation of a fair colour, unbroken veils, and an acceptable texture during 3 days. This beneficial effect was attributed to the combination of a medium CO2 (9.5 kPa) and low O2 (2.5 kPa) partial pressure, without condensation. The main drawback of using WG-coated paper was its high water vapour permeability that led to an important weight loss (3.8 wt.% on day 3). However it did not affect the overall quality of mushrooms within the storage duration.
Industrial relevance
Even with the development of micro-perforated materials that provide the largest range of O2 and CO2 permeability values, several limitations are still encountered for synthetic MAP applications such as- – an insufficient perm-selectivity ratio that remains lower than 6 (value of 1 for micro-perforated material): generated atmosphere cannot reach both low O2 and low CO2 partial pressures and then are not adapted to CO2-sensitive fresh produces.
- – unattractive water condensation at the inner surface of the packaging that might occur due to a low water vapour permeability, favouring the development of microorganisms.
- – their non biodegradability.
136.
Ferdinando Costantino Pier Luigi Gentili Nathalie Audebrand 《Inorganic chemistry communications》2009,12(5):406-408
A new pillared cerium(IV) sulfate–diphosphonate with formula Ce2(2H2O)[(O3PCH2)–NC10H18N–(CH2PO3)(SO4)2] · 6H2O has been hydrothermally synthesized and its structure has been solved ab initio from laboratory X-ray powder diffraction data.The luminescent and thermal properties of this compound have been preliminarily studied and the encouraging results place it in the field of functional hybrid materials. 相似文献
137.
Serge Laplante Nathalie Souchet Piotr Bryl 《European Journal of Lipid Science and Technology》2009,111(2):135-141
Among the fat fish species available from Eastern Quebec (Canada), whole Atlantic mackerel (Scomber scombrus) and herring (Clupea harengus) represent abundant fishery resources which are currently under‐utilized. They have relatively high contents of oil and coenzyme Q10 (CoQ10) in their tissues, which could be valuable for nutraceutical applications. Therefore, two low‐temperature extraction processes were compared for the recovery of oil and CoQ10 from these resources, such as enzymatic hydrolysis using Protamex? and supercritical CO2 (SCO2) using fish lyophilizates. The results revealed that highest yields of oil and CoQ10 were obtained using the enzymatic hydrolysis process with mackerel. Whatever the process used, CoQ10 concentrations were higher in herring oil, due mainly to a more selective extraction of CoQ10 over that of the oil. The highest CoQ10 recovery rates (extraction efficiencies) were obtained using the enzymatic hydrolysis process with both types of fish, but also the SCO2 process with herring under some conditions. For mackerel, the lower CoQ10 recovery rates obtained from the SCO2 process were explained by its more important matrix effect. An economic assessment of both processes revealed that the enzymatic hydrolysis extraction process would be the most promising for up‐scaling the recovery of oil and CoQ10 from these resources. 相似文献
138.
François De Vleeschouwer Nathalie Fagel Anna Pazdur Nadine Mattielli Barbara Fialkiewicz Gaël Le Roux 《The Science of the total environment》2009,407(21):5674-5684
Lead pollution history over Northern Poland was reconstructed for the last ca. 1300 years using the elemental and Pb isotope geochemistry of a dated Polish peat bog. The data show that Polish Pb-Zn ores and coal were the main sources of Pb, other heavy metals and S over Northern Poland up until the industrial revolution. After review of the potential mobility of each element, most of the historical interpretation was based on Pb and Pb isotopes, the other chemical elements (Zn, Cu, Ni, S) being considered secondary indicators of pollution. During the last century, leaded gasoline also contributed to anthropogenic Pb pollution over Poland. Coal and Pb-Zn ores, however, remained important sources of pollution in Eastern European countries during the last 50 years, as demonstrated by a high 206Pb/207Pb ratio (1.153) relative to that of Western Europe (ca. 1.10). The Pb data for the last century were also in good agreement with modelled Pb inventories over Poland and the Baltic region. 相似文献
139.
Piotr Wacinski Mariusz Gadzinowski Wojciech Dabrowski Justyna Szumilo Jakub Wacinski Nathalie Oru Eric Vicaut Stanislaw Czuczwar Janusz Kocki Teresa Basinska Stanislaw Slomkowski 《International journal of molecular sciences》2021,22(14)
Atherosclerosis involves an ongoing inflammatory response of the vascular endothelium and vessel wall of the aorta and vein. The pleiotropic effects of statins have been well described in many in vitro and in vivo studies, but these effects are difficult to achieve in clinical practice due to the low bioavailability of statins and their first-pass metabolism in the liver. The aim of this study was to test a vessel wall local drug delivery system (DDS) using PLA microstructures loaded with simvastatin. Wistar rats were fed high cholesterol chow as a model. The rat vessels were chemically injured by repeated injections of perivascular paclitaxel and 5-fluorouracil. The vessels were then cultured and treated by the injection of several concentrations of poly(L,L-lactide) microparticles loaded with the high local HMG-CoA inhibitor simvastatin (0.58 mg/kg) concentration (SVPLA). Histopathological examinations of the harvested vessels and vital organs after 24 h, 7 days and 4 weeks were performed. Microcirculation in mice as an additional test was performed to demonstrate the safety of this approach. A single dose of SVPLA microspheres with an average diameter of 6.4 μm and a drug concentration equal to 8.1% of particles limited the inflammatory reaction of the endothelium and vessel wall and had no influence on microcirculation in vivo or in vitro. A potent pleiotropic (anti-inflammatory) effect of simvastatin after local SVPLA administration was observed. Moreover, significant concentrations of free simvastatin were observed in the vessel wall (compared to the maximum serum level). In addition, it appeared that simvastatin, once locally administered as SVPLA particles, exerted potent pleiotropic effects on chemically injured vessels and presented anti-inflammatory action. Presumably, this effect was due to the high local concentrations of simvastatin. No local or systemic side effects were observed. This approach could be useful for local simvastatin DDSs when high, local drug concentrations are difficult to obtain, or systemic side effects are present. 相似文献
140.
This paper presents a new millimeter-wave (MMW) ultra wideband (UWB) transmitter MMIC which has been developed in an OMMIC 0.1 μm GaAs PHEMT foundry process (ft = 100 GHz) for 22-29 GHz vehicular radar systems. The transmitter is composed of an MMW negative resistance oscillator (NRO), a power amplifier (PA), and two UWB pulse generators (PGs). In order to convert the UWB pulse signal to MMW frequency and reduce the total power consumption, the MMW NRO is driven by one of the UWB pulse generators and the power amplifier is triggered by another UWB pulse generator. The main advantages of this transmitter are: new design, simple architecture, high-precision distance measurements, infinite ON/OFF switch ratio, and low power consumption. The total power consumption of the transmitter MMIC is 218 mW with a peak output power of 5.5 dBm at 27 GHz. 相似文献