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111.
The effects of finishing time, (T0 = 0, T1 = 30 and T2 = 60 days), on Holstein–Friesian cull cows (n = 18) and post-mortem ageing, (1, 7, 14, 21, 35 and 42 days), under vacuum conditions of Longissimus thoracis (LT) muscles were investigated. The objective of this research was to study how finishing feeding (based on a commercial concentrate and corn silage), following a pasture period of 90 days, affected carcass and meat quality. Ageing time effect was also evaluated on the main quality attribute of added value pieces, such as “striploin of ox” from cull cows. Finishing treatment affected intramuscular fat content (IMF), moisture percentage, water-holding capacity (WHC), colour parameters and shear force of meat at 24 h post-mortem, whereas ageing time enhanced meat tenderness, when this was measured by two textural tests, Warner–Braztler (WB) and textural profile analysis (TPA). A minimum shear force was achieved at 7 and 14 days of ageing for T1 and T2, respectively. No differences (P > 0.05) could be found in colour parameters from 7 to 42 days. The results show that a finishing time of two months is very beneficial, due to the increase in meat fatness, improved overall carcass quality and luminosity (L*). Furthermore, 14 ageing days were sufficient to improved tenderness. Ageing time did not have an effect on lipid oxidation (P > 0.05) and this leads us to conclude that meat shelf life exceeded 42 days under vacuum conditions’.  相似文献   
112.
One of the main challenges faced by mankind in the 21st century is to meet the increasing demand for energy requirements by means of a more sustainable energy supply. In countries that are net fossil fuel importers, expectation about the benefit of using alternative fuels on reducing oil imports is the primary driving force behind efforts to promote its production and use. Spain is scarce in domestic energy sources and more than 50% of the energy used is fossil fuel based. The promotion of renewable energies use is one of the principal vectors in the Spanish energy policy. Selected herbaceous crops such as Brassica carinata are currently under study as potential energy sources. Its biomass can be considered as potential feedstock to ethanol conversion by an enzymatic process due to the characteristics of its composition, rich in cellulose and hemicellulose. This paper aims to analyse the environmental performance of two ethanol-based fuel applications (E10 and E85) in a passenger car (E10 fuel: a mixture of 10% ethanol and 90% gasoline by volume; E85 fuel: a mixture of 85% ethanol and 15% gasoline by volume) as well as their comparison with conventional gasoline as transport fuel. Two types of functional units are applied in this study: ethanol production oriented and travelling distance oriented functional units in order to reflect the availability or not of ethanol supply. E85 seems to be the best alternative when ethanol production based functional unit is considered in terms of greenhouse gas (GHG) emissions and E10 in terms of non-renewable energy resources use. Nevertheless, E85 offers the best environmental performance when travelling distance oriented functional unit is assumed in both impacts. In both functional unit perspectives, the use of ethanol-based fuels reduces the global warming and fossil fuels consumption. However, the contributions to other impact indicators (e.g. acidification, eutrophication and photochemical oxidants formation) were lower for conventional gasoline.Life Cycle Assessment (LCA) procedure helps to identify the key areas in the B. carinata ethanol production life cycle where the researchers and technicians need to work to improve the environmental performance. Technological development could help in lowering both the environmental impact and the prices of the ethanol fuels.  相似文献   
113.
The effects of low-energy (≤2 kV) Ar+ irradiation on the optical and structural properties of zinc oxide (ZnO) nanowires (NWs) grown by a simple and cost-effective low-temperature technique were investigated. Both photoluminescence spectra from ZnO NW-coated films and cathodoluminescence analysis of individual ZnO NWs demonstrated obvious evidences of ultraviolet/visible luminescent enhancement with respect to irradiation fluence. Annihilation of the thinner ZnO NWs after the ion bombardment was appreciated by means of high-resolution scanning electron microscopy and transmission electron microscopy (TEM), which results in an increasing NW mean diameter for increasing irradiation fluences. Corresponding structural analysis by TEM pointed out not only significant changes in the morphology but also in the microstructure of these NWs, revealing certain radiation-sensitive behavior. The possible mechanisms accounting for the decrease of the deep-level emissions in the NWs with the increasing irradiation fluences are discussed according to their structural modifications.  相似文献   
114.
In the last years, Service Overlay Networks (SONs) have emerged as a promising means to address some of the issues (e.g. end‐to‐end QoS) affecting the current Internet and to favor the development and deployment of new value‐added Internet services. The deployment of an SON is a capital‐intensive investment, since bandwidth with certain QoS guarantees must be purchased from the individual network domains through bilateral Service Level Agreements. Thus, minimizing the economic cost of the logical end‐to‐end service delivery infrastructure is one of the key objectives for the SON provider. When a SON is aimed at end‐to‐end QoS provisioning, its topology must be designed so as to also satisfy the specific requirements of QoS‐sensitive applications. This paper deals with the problem of planning the SON topology in order to take into account both cost and QoS constraints. More specifically, the paper proposes a set of new algorithms for the design of an optimized SON topology, which minimizes the economic cost while simultaneously meeting bandwidth and delay constraints. A performance comparison among such algorithms is finally carried out. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
115.
Lamb loins were subjected to sous-vide cooking at different combinations of temperature (60, 70, and 80 °C) and time (6, 12, and 24 h). Different physicochemical, histological and structural parameters were studied. Increasing cooking temperatures led to higher weight losses and lower moisture contents, whereas the effect of cooking time on these variables was limited. Samples cooked at 60 °C showed the highest lightness and redness, while increasing cooking temperature and cooking time produced higher yellowness values. Most textural variables in a texture profile analysis showed a marked interaction between cooking temperature and time. Samples cooked for 24 h showed significantly lower values for most of the studied textural parameters for all the temperatures considered. Connective tissue granulation at 60 °C and gelation at 70 °C were observed in the SEM micrographs. The sous-vide cooking of lamb loins dramatically reduced microbial population even with the less intense heat treatment studied (60 °C–6 h).  相似文献   
116.
This work reports the development of a novel class of affinity co-polymeric materials using supercritical fluid technology. Polymeric materials with molecular recognition to flufenamic acid, were first synthesized in supercritical carbon dioxide (scCO2) using the drug as template. Molecularly imprinted co-polymers of methacrylic acid (MAA) or N-isopropyl acrylamide (NIPAAm) crosslinked with ethylene glycol dimethacrylate (EGDMA) were synthesized using different crosslinking degrees and template:monomer ratios, at 65 °C and 21 MPa. High-pressure NMR experiments confirmed that the nature of the interactions between the drug and the functional monomers during the polymerization step are mainly hydrogen bonds. scCO2-assisted impregnation revealed that the imprinted matrices were able to uptake higher amounts of flufenamic acid. This effect was particularly evidenced in the more crosslinked matrices, with P(MAA-EGDMA) imprinted copolymers binding up to 101.5 mg drug/g polymer against only 50.5 mg/g in the non-imprinted copolymer. In vitro drug delivery experiments showed that imprinted co-polymers release the drug in a more sustained way than the corresponding non-imprinted matrices. Overall it was shown that supercritical fluid technology is a viable approach for the development of self-assembly molecular recognition polymers with potential application in controlled drug delivery systems.  相似文献   
117.
Spray-dried high-amylose sodium carboxymethyl starch (SD HASCA) is a promising pharmaceutical excipient for sustained-release (SR) matrix tablets produced by direct compression. The presence of α-amylase in the gastrointestinal tract and the variations of the gastric residence time of non-disintegrating dosage forms may affect the presystemic metabolism of this excipient and, consequently, the drug-release profile from formulations produced with SD HASCA. In this study, the influence of α-amylase and the residence time in acidic conditions on the drug-release profile was evaluated for a once-daily acetaminophen formulation (Acetaminophen SR) and a once-daily tramadol hydrochloride formulation (Tramadol SR). Both formulations were based on SD HASCA. α-Amylase concentrations ranging from 0?IU/L to 20000?IU/L did not significantly affect the drug-release profiles of acetaminophen and tramadol hydrochloride from SD HASCA tablets (f2?>?50) for all but only one of the studied conditions (f2?=?47). Moreover, the drug-release properties from both SD HASCA formulations were not significantly different when the residence time in acidic medium was 1?h or 3?h. An increase in α-amylase concentration led to an increase in the importance of polymer erosion as the main mechanism of drug-release instead of drug diffusion, for both formulations and both residence times, even if release profiles remained comparable. As such, it is expected that α-amylase concentration and residence time in the stomach will not clinically affect the performance of both SD HASCA SR formulations, even if the mechanism of release itself may be affected.  相似文献   
118.
Herbhoney is a honey-like substance produced by bees fed on a saccharose-based food supplemented with herbal extracts or fruit juices. Having specific sensory characteristics (colour, aroma and taste), different from those of natural honeys, herbhoneys greatly extend the range of bee products. With the aim of improving the knowledge of herbhoneys of various origins, their chosen physicochemical and quality parameters were evaluated. It was found that the herbhoneys studied satisfied most of the requirements relative to natural honeys (water, hydroxymethylfurfural and saccharose contents, free acidity, and diastase number). Some of the samples showed an increased specific conductivity, characteristic of honeydew honeys, although the ash contents of herbhoneys were at a level typical of nectar honeys. The saccharose content of some herbhoneys exceeded the value allowed for most natural honeys. Mineral composition varied between the samples, being in most cases within the limits reported in this literature for natural honeys.  相似文献   
119.
Model solutions (pH = 3.5, 12% ethanol) of malvidin 3-O-glucoside (Mv3glc), the most common free anthocyanin in grapes and red wines from Vitis vinifera, and three free hydroxycinnamic acids present in wines (caffeic, ferulic and p-coumaric acids) were studied.  相似文献   
120.
Environmental impact assessment is an intrinsically complex multi-dimensional process which involves multiple criteria and multiple actors. Multi-criteria methods can serve as useful decision aids for carrying out environmental impact assessment. This paper proposes the use of a multi-criteria technique, namely the analytic hierarchy process, as a potential decision-making method for use in management maintenance processes. In this case, our problem concerns the selection of a parts cleaning system for diesel engine maintenance. A hierarchical structure is built for the prequalification of the criteria and the alternatives within the system. By applying the analytic hierarchical process, the criteria can be prioritized and the alternatives can be organized in descending order so that the best parts cleaning system may be selected.  相似文献   
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