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121.
Carmen Marchiori Susan Stratton Sayre Leo K. Simon 《Water Resources Management》2012,26(10):2799-2816
Governments are increasingly reliant on the reacquisition of water rights as a mechanism for recovering overexploited basins. Yet, serious concerns have recently been raised about the efficacy and operational dimensions of existing programs. Water buyback is typically implemented as the purchase of a fixed quantity of water rights from the agricultural sector at the price set by the Water Authority. This paper seeks to analyze whether the use of water buyback in its current form represents a sensible means of recovering overexploited basins. The results??which are particularly relevant to contexts characterised by poor enforcement regimes and widespread illegal water use??highlight the need for greater scrutiny of current programs and call for additional work to improve the design of reacquisition policies in the context of water resource management. 相似文献
122.
Carmen Diaz-Amigo 《Food Analytical Methods》2010,3(4):351-356
There are several enzyme-linked immunosorbent assay (ELISA) kits in the market that have been proven to be useful for the
determination of egg in foods. However, inconsistent results that are obtained when different kits are used make the selection
of one kit over another very difficult. Two different approaches were used to help understand why results vary among kits.
Different kits were used to analyze spiked egg material [NIST reference material (RM) 8445] in wheat flour (raw ingredients)
and cookies containing egg as an ingredient baked for different periods of time (processed food). These results were compared
with immunoblotting using conjugated antibodies from the commercial kits to determine the antibody specificity and sample
extraction efficiency. ELISA results can be difficult to compare because reporting units differ among kits. Results from both
ELISA and immunoblotting are in agreement regarding the decreased detection of proteins in baked cookie extracts. Moreover,
immunoblotting showed that this reduction is due to reduced protein content in these extracts. However, a properly selected
extraction solution may help improve the solubility of certain egg proteins in processed foods. Harmonization of the reporting
unit system along with the use of a common reference material is recommended as the path forward in the standardization of
detection methods for food allergens. This would assist the end user in making an informed decision regarding the selection
of the most appropriate kit for his or her purpose. 相似文献
123.
Carmen Bain 《Biomass & bioenergy》2011,35(4):1400-1407
The rapid expansion of ethanol plants across the U.S. state of Iowa has fueled debate about the burdens and benefits of local (in-state investors) versus non-local ownership of biorefineries. Central to these concerns is the extent to which non-local, absentee owners might reap the benefits of the ethanol industry at the expense of local communities. A key argument within the rural development literature is that local ownership of firms has a positive effect on the long-term well-being and sustainability of the communities in which they are situated. This literature asserts that firms operate at different scales, with local firms embedded within local supply chains and institutions, and non-local firms embedded within national and international networks and institutions. Conversely, there is a growing body of work within the alternative agrifood systems literature that cautions against the ‘local trap’; the assumption that the local scale is inherently good and therefore advantageous. Despite this broader debate, the literature on local ownership and renewable energy remains limited. This paper addresses this gap by drawing on case study research of the community effects of ethanol plant ownership structure from the perspective of community leaders. My findings suggest that differences between the structure and effects of local versus non-local ownership of firms on communities are rather more ambiguous than the literature asserts. Therefore, assumptions about the benefits of local ownership may be overstated and concepts of ‘local’ and ‘non-local’ may be inadequate for considering firm outcomes on the civic welfare and socioeconomic well-being of a community. 相似文献
124.
The work outlined here aims to build and examine contradiction measures on Atanassov intuitionistic fuzzy sets (A-IFS) that are defined in this particular case in finite universes. The axiomatic definition of contradiction measure in the A-IFS framework was given in [7]. A number of axioms formalizing the concept of continuity for the above measures were also given. In this paper, Section 1, which briefly discusses the preliminaries required to develop the work, is followed by a section analysing how the restriction of the universe of discourse to a finite set influences the continuity axioms. The following three sections look at three types of specific contradiction measures. In Section 3, continuous t-norms and fuzzy negations are used to construct a large family of measures. These measures satisfy different types of continuity, which are examined at length. Then, Sections 4 Contradiction measures from geometrical methods, 5 Contradiction measures in reference to the region of non- take up other families introduced in [8], [10], [9], proving that their behaviour with respect to continuity is better than it was in the earlier articles because the universes considered here are finite. 相似文献
125.
Silvia Baena‐Ruano Carlos Jiménez‐Ot Inés M. Santos‐Dueñas Jorge E. Jiménez‐Hornero José L. Bonilla‐Venceslada Carmen Álvarez‐Cáliz Isidoro García‐García 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2010,85(7):908-912
BACKGROUND: The acetification process needs an overall study of the variables influencing it in order to establish their optimum values. Based on industrial experience and available literature, including a recently proposed model by the authors, among the variables most strongly influencing the acetification process are the ethanol concentration at the time the reactor is unloaded, the unloaded volume and the loading rate. To ensure economically efficient industrial production of vinegar, and to check the predictions of the aforementioned model, the influence of the final ethanol concentration at unloading time on the mean acetification rate and on productivity has been studied in this work. RESULTS: An increase in the final ethanol concentration from 0.5 to 3.5% (v/v) increased the mean overall acetification rate and acetic acid production by 38 and 26%, respectively. The increase was established mainly during the loading phase. CONCLUSIONS: The final ethanol concentration is a key variable for process optimization. If a high rate is desired then a product containing much unused substrate will be obtained, which may be industrially unacceptable. These results suggest the necessity to investigate other possibilities when high values for yield and productivity must to be achieved. Copyright © 2010 Society of Chemical Industry 相似文献
126.
Stability of dolphinfish (Coryphaena hippurus) and sardines (Sardina pilchardus) of different fat content (lean and fatty sardines) during frozen storage and its suitability for cold-smoking throughout storage were evaluated in order to overcome seasonal and excess catches of these species. Dolphinfish showed a relative stability regarding protein functionality (protein solubility, apparent viscosity, water and lipid holding capacity), lipid oxidation and total volatile basic nitrogen (TVBN) accumulation, which led to high acceptability ratings of the resulting smoked product throughout frozen storage (340 days). However, both lean and fatty sardines showed a marked loss of protein functionality, which coincided with the accumulation of oxidation products and TVBN. Freezing of raw muscle may become a valuable preservation method for the smoking industry to overcome the short caught period of dolphinfish in the Balearic Islands and to make use of excess catches of both, lean and fatty sardine. High quality smoked products may be obtained from the frozen muscle during approximately twelve, four and two months of frozen storage for Dolphinfish, lean and fatty sardine, respectively. 相似文献
127.
Volatile fatty acids production from cheese whey: influence of pH,solid retention time and organic loading rate 下载免费PDF全文
128.
María Dolores Ayala Isaac Abdel Carmen Martínez Francisco Gil Octavio López Albors 《LWT》2010,43(3):465-17
Sea bream, Sparus aurata L., specimens were studied in pre-rigor (3 h) and during the following post-mortem days: 1, 5, 10, 15 and 22. Muscle and textural parameters were evaluated on 6 specimens/stage. Structural results showed scarce fibre-to-fibre detachment on pre-rigor, which increased during the post-mortem degradation. Ultrastructural changes revealed rapid muscle degradation. In pre-rigor myofibrils were detached to both sarcolemma and endomysium. Intermyofibrillar spaces increased and some mitochondriae and sarcoplasmic reticulum were swollen. After 1 day, the sarcolemma appeared occasionally disrupted and the interfibrillar spaces increased. From 5 to 10 days, the I-band and Z line presented some alterations, although these were more severe at 15-22 days. Thus, in these two last stages, loss of I-band, Z line and actin filaments was observed, that coincides with the alteration of the hexagonal arrangement in these advanced stages. Also, the fragmentation of myofibrils increased from 5 to 10 days on. Sarcolemma and endomysium were gradually disrupted throughout the post-mortem stages with total loss at 22 days. Consequently, the interfibrillar spaces increased at last stages. Autophagic mechanisms increased from 5 days on, with an intense destruction of all the intracytoplasmic organelles. Textural parameters decreased from pre-rigor until 5-10 days, mainly associated to detachment of myofibers to sarcolemma-endomysium. 相似文献
129.
Marta Izquierdo Carmen Gabaldón Paula Marzal 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2013,88(4):606-614
BACKGROUND: The applicability of biosorption for the treatment of metal plating wastewater is adversely affected by the presence of complexing agents. To investigate this limitation on the removal of copper(II) onto peat, batch and column experiments were carried out using EDTA as the model complexing agent. The influence of pH and copper(II):EDTA mass ratios were evaluated for copper(II) concentrations between 5 and 100 mg Cu(II) dm?3. RESULTS: EDTA negatively affected the copper(II) uptake of peat for pH > 5. Batch and column experiments showed that copper(II)‐EDTA complexes were not sorbed by peat. The leaks of copper(II) detected from the beginning of the column operation matched the copper(II)‐EDTA concentration in the feed solutions. To overcome the interference of EDTA, a novel approach based on the combination of peat + activated carbon was proposed. Nearly complete removal of copper(II) was maintained over 70 h in the treatment of a solution containing 20 mg Cu(II) dm?3 with 11% of copper(II)‐EDTA complexes. CONCLUSION: A new mass transport model coupling copper(II) speciation in the feed and mass transfer rate‐controlled process simulated the copper(II) breakthrough curves in the presence of EDTA and could be used to successfully predict the breakthrough point. This work demonstrated that biosorption can also be applied for the treatment of wastewater containing complexing agents with the proper combination of sorbent materials. © 2012 Society of Chemical Industry 相似文献
130.
An automatic purge and trap apparatus, coupled to a GC-MS was used to study the seasonal variability of the volatile fraction of raw milk Manchego cheese. Both season and dairy significantly affected abundance of most volatile compounds. Most aldehydes, methyl ketones, n-alcohols, and secondary alcohols reached significantly higher concentrations in spring cheeses. Branched chain alcohols showed significantly higher concentrations in autumn and winter cheeses, while significantly higher amounts of diketones were found in summer cheeses. Most ethyl esters reached higher concentrations in spring and winter cheeses and lower in autumn cheeses. Lower concentrations of alpha-pinene were found in spring cheeses, and higher amounts of limonene were observed in winter cheeses. Heptane and octane were significantly more abundant in summer cheeses. No significant seasonal differences were found either for quality or intensity scores. 相似文献