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11.
All water use in the world is ultimately linked to final consumption by consumers. It is therefore interesting to know the specific water requirements of various consumer goods, particularly the water-intensive ones. This information is relevant not only for consumers, but also for food processors, retailers, and traders. The objective of this paper is to carry out a pilot study on water footprint accounting and impact assessment for a hypothetical sugar-containing carbonated beverage in a 0.5 l PET-bottle produced in a hypothetical factory that takes its sugar alternatively from sugar beet, sugar cane and high fructose maize syrup and from different countries. The composition of the beverage and the characteristics of the factory are hypothetical but realistic. The data assumed have been inspired by a real case. This paper does not only look at the water footprint of the ingredients of the beverage, but also at the water footprint of the bottle, other packaging materials and construction materials, paper and energy used in the factory. Although most companies focus on their own operational performance, this paper shows that it is important to consider freshwater usage along the supply chain. The water footprint of the beverage studied has a water footprint of 150 to 300 l of water per 0.5 l bottle, of which 99.7–99.8% refers to the supply chain. The study also shows that agricultural ingredients that constitute only a small fraction in weight of the final product have the biggest share at the total water footprint of a product.  相似文献   
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13.
Traditionally air quality networks have been carrying out the continuous, on-line measurement of volatile organic compounds (VOC) in ambient air with GC-FID. In this paper some identification and coelution problems observed while using this technique in long-term measurement campaigns are described. In order to solve these problems a GC-MS was set up and operated simultaneously with a GC-FID for C2-C11 VOCs measurement.There are few on-line, unattended, long term measurements of atmospheric VOCs performed with GC-MS. In this work such a system has been optimized for that purpose, achieving good repeatability, linearity, and detection limits of the order of the GC-FID ones, even smaller in some cases. VOC quantification has been made by using response factors, which is not frequent in on-line GC-MS. That way, the identification and coelution problems detected in the GC-FID, which may led to reporting erroneous data, could be corrected.The combination of GC-FID and GC-MS as complementary techniques for the measurement of speciated VOCs in ambient air at sub-ppbv levels is proposed. Some results of the measurements are presented, including concentration values for some compounds not found until now on public ambient air VOC databases, which were identified and quantified combining both techniques. Results may also help to correct previously published VOC data with wrongly identified compounds by reprocessing raw chromatographic data.  相似文献   
14.
Pijuan M  Werner U  Yuan Z 《Water research》2011,45(16):5075-5083
One of the main challenging issues for the aerobic granular sludge technology is the long startup time when dealing with real wastewaters. This study presents a novel strategy to reduce the time required for granulation while ensuring a high level of nutrient removal. This new approach consists of seeding the reactor with a mixture of crushed aerobic granules and floccular sludge. The effectiveness of the strategy was demonstrated using abattoir wastewater, containing nitrogen and phosphorus at approximately 250 mgN/L and 30 mgP/L, respectively. Seven different mixtures of crushed granules and floccular sludge at granular sludge fractions (w/w in dry mass) of 0%, 5%, 10%, 15%, 25%, 30% and 50% were used to start eight granulation processes. The granulation time (defined as the time when the 10th percentile bacterial aggregate size is larger than 200 μm) displayed a strong dependency on the fraction of granular sludge. The shortest granulation time of 18 days was obtained with 50% crushed granules, in comparison with 133 days with 5% crushed granules. Full granulation was not achieved in the two trials without seeding with crushed granules. In contrast to the 100% floccular sludge cases, where a substantial loss of biomass occurred during granulation, the biomass concentration in all other trails did not decrease during granulation. This allowed that good nitrogen removal was maintained in all the reactors during the granulation process. However, enhanced biological phosphorus removal was achieved in only one of the eight trials. This was likely due to the temporary accumulation of nitrite, a strong inhibitor of polyphosphate accumulating organisms.  相似文献   
15.
BACKGROUND: In this study the antimicrobial effectiveness of oregano and sage essential oils (EOs) incorporated into two different matrices, whey protein isolate (WPI) and cellulose‐based filter paper, was analysed. RESULTS: Antimicrobial properties of WPI‐based films containing oregano and sage EOs were tested against Listeria innocua, Staphylococcus aureus and Salmonella enteritidis. Oregano EO showed antimicrobial activity against all three micro‐organisms. The highest inhibition zones were against L. innocua. However, sage EO did not show antimicrobial activity against any of the micro‐organisms. Antimicrobial activity was confirmed for both EOs using cellulose‐based filter paper as supporting matrix, although it was significantly more intense for oregano EO. Inhibition surfaces were significantly greater when compared with those of the WPI films. This finding is likely due to the higher porosity and diffusivity of the active compounds in the filter paper. CONCLUSION: The interactions between the EOs and the films have a critical effect on the diffusivity of the active compounds and therefore on the final antimicrobial activity. As a result, to obtain active edible films, it is necessary to find the equilibrium point between the nature and concentration of the active compounds in the EO and the formulation of the film. Copyright © 2010 Society of Chemical Industry  相似文献   
16.
Biodegradable self‐reinforced films of poly (3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBV) and PHBV microparticles were prepared through the solvent casting method (srPHBV). Differential scanning calorimetry (DSC), wide angle X‐ray scattering (WAXS) and polarized optical microscopy results confirmed the nucleating effect of PHBV microparticles. WAXS proved that diffractograms of PHBV and srPHBV‐6 films at room temperature contain the main characteristic diffraction peaks of an orthorhombic α‐type crystalline structure. Small angle X‐ray scattering (SAXS) showed a similar decrement rate of long spacing in PHBV and srPHBV films. SAXS/WAXS data revealed that when the amount of filler was increased, lamellae thickness grew. Transmission electron microscopy images illustrated well filler dispersion in the srPHBV films. Scanning electron microscopy results exhibited a significant reduction in porosity for srPHBV films once the PHBV microparticles were added. Atomic force microscopy analysis showed higher surface roughness after filler incorporation. Samples of srPHBV films showed higher barrier properties against water vapor, oxygen, and carbon dioxide. Combined properties of srPHBV films revealed the possibility of being suitable candidates for food packaging applications. POLYM. ENG. SCI., 59:E120–E128, 2019. © 2018 Society of Plastics Engineers  相似文献   
17.
In this study we analyse gender equality in the preparation, supervision and defence of PhD theses in Spain in the period 1990–2004. The results indicate a tendency towards greater equality in the number of men and women successfully completing doctoral studies. However, the gender imbalance among thesis supervisors and on thesis assessment boards is more apparent, with a predominance of male academics. Moreover, the gender of the PhD student is clearly related to the gender of the supervisor, and both are related to the gender of the members of the assessment boards of PhD theses in Spain.  相似文献   
18.
Adulteration of canola oil with four potential edible oils was analysed using FT-IR and chemometric methods. The adulterants (corn, peanut, soya bean and sunflower oils) were studied in four different proportions (canola oil + adulterant oils: 90 + 10, 95 + 5, 98 + 2 and 99 + 1 in volume). Excellent classification results were obtained when multi-class approaches were performed with a maximum error of 3%, using 1630 or 16 wavenumbers as variables. In the case of one-class approaches, the selection of variables (16 wavenumbers) was necessary, improving the classification error to 5%. The differences observed using the different methods were related to the nature of each model depending on how the boundaries are set in each of them, responding either to a PCA-based or PLS-based algorithm.  相似文献   
19.
Mouse hepatitis virus (MHV) receptor, the receptor for the murine coronavirus MHV, was expressed in MHV-resistant hamster and human cells as a series of mutant, recombinant glycoproteins with carboxy-terminal deletions lacking the cytoplasmic tail, transmembrane domain, and various amounts of the immunoglobulin constant-region-like domains. The soluble receptor glycoproteins containing the N-terminal virus-binding domain were released into the supernatant medium and inactivated the infectivity of MHV-A59 virions in a concentration-dependent manner. Surprisingly, some of the anchorless glycoproteins were found on the plasma membranes of transfected cells by flow cytometry, and these cells were rendered susceptible to infection with three strains of MHV. Thus, in the cells in which the anchorless, recombinant receptor glycoprotein is synthesized, some of the protein is bound to an unidentified moiety on the plasma membrane, which allows it to serve as a functional virus receptor.  相似文献   
20.
We present the RST Signalling Corpus (Das et al. in RST signalling corpus, LDC2015T10. https://catalog.ldc.upenn.edu/LDC2015T10, 2015), a corpus annotated for signals of coherence relations. The corpus is developed over the RST Discourse Treebank (Carlson et al. in RST Discourse Treebank, LDC2002T07. https://catalog.ldc.upenn.edu/LDC2002T07, 2002) which is annotated for coherence relations. In the RST Signalling Corpus, these relations are further annotated with signalling information. The corpus includes annotation not only for discourse markers which are considered to be the most typical (or sometimes the only type of) signals in discourse, but also for a wide array of other signals such as reference, lexical, semantic, syntactic, graphical and genre features as potential indicators of coherence relations. We describe the research underlying the development of the corpus and the annotation process, and provide details of the corpus. We also present the results of an inter-annotator agreement study, illustrating the validity and reproducibility of the annotation. The corpus is available through the Linguistic Data Consortium, and can be used to investigate the psycholinguistic mechanisms behind the interpretation of relations through signalling, and also to develop discourse-specific computational systems such as discourse parsing applications.  相似文献   
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