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481.
While many studies and reviews into the practices conducted by industry and academia to recycle and remanufacture carbon fibre-reinforced plastic (CFRP) exist, to date no investigation exists which regards the correctness of the use of the terms recycling and remanufacturing. As such, this paper seeks to analyse the CFRP reuse industry’s attempt to recycle and remanufacture manufacturing waste CFRP and end-of-life (EOL) CFRP with an emphasis on the terminology used to describe these practices. Firstly, this paper presents a justification of the importance of using EOL terminology correctly; outlining the benefits and problems associated with using the correct and incorrect terminology. This paper finds that in the case of CFRP remanufacturing, terminology is being applied incorrectly and in the case of CFRP recycling, particular care should be taken when applying the term recycled to CFRP or stating that CFRP has been recycled. Further, this paper proposes new terminology (in keeping with EU directives) which could be adopted by industry and academia working in this area. This paper also finds that in the case of remanufacture, CFRP is incapable of being remanufactured.  相似文献   
482.
Nickel–metal hydride (NiMH) batteries contain high amount of industrial metals, especially iron, nickel, cobalt and rare earth elements. Although the battery waste is a considerable secondary source for metal and chemical industries, a recycling process requires a suitable pretreatment method before proceeding with recovery step to reclaim all valuable elements. In this study, AA- and AAA-type spent NiMH batteries were ground and then sieved for size measurement and classification. Chemical composition of the ground battery black mass and sorted six different size fractions were determined by an analytical technique. Crystal structures of the samples were analyzed by X-ray diffraction. Results show that after mechanical treatment, almost 87 wt% of the spent NiMH batteries are suitable for further recycling steps. Size classification by sieving enriched the iron content of the samples in the coarse fraction which is bigger than 0.25 mm. On the other hand, the amounts of nickel and rare earth elements increased by decreasing sample size, and concentrated in the finer fractions. Anode and cathode active materials that are hydrogen storage alloy and nickel hydroxide were mainly collected in finer size fraction of the battery black mass.  相似文献   
483.
Self-binding ability of the pectin molecules was used to produce pectin films using the compression molding technique, as an alternative method to the high energy-demanding and solvent-using casting technique. Moreover, incorporation of fungal biomass and its effects on the properties of the films was studied. Pectin powder plasticized with 30% glycerol was subjected to heat compression molding (120 °C, 1.33 MPa, 10 min) yielding pectin films with tensile strength and elongation at break of 15.7 MPa and 5.5%, respectively. The filamentous fungus Rhizopus oryzae was cultivated using the water-soluble nutrients obtained from citrus waste and yielded a biomass containing 31% proteins and 20% lipids. Comparatively, the same strain was cultivated in a semi-synthetic medium resulting in a biomass with higher protein (60%) and lower lipid content (10%). SEM images showed addition of biomass yielded films with less debris compared to the pectin films. Incorporation of the low protein content biomass up to 15% did not significantly reduce the mechanical strength of the pectin films. In contrast, addition of protein-rich biomass (up to 20%) enhanced the tensile strength of the films (16.1–19.3 MPa). Lastly, the fungal biomass reduced the water vapor permeability of the pectin films.  相似文献   
484.
The potential use of poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/graphite nanosheets (GNS) as a biodegradable nanocomposite has been explored. PHBV/GNS nanocomposites films were prepared by solution casting at various concentrations of GNS—0.25, 0.50 and 1.00 wt% GNS. The films were exposed to artificial ultraviolet radiation (UV) during 52 h. The effect of GNS on PHBV photodegradation was investigated and compared to neat PHBV film. The artificial photodegradation induced changes in physical (weight loss), chemical carbonyl index by Fourier transform infrared spectroscopy, thermal degree of crystallinity and melting temperature by differential scanning calorimetry and morphological scanning electron microscopy characteristics. Based on the results obtained from aforementioned analyzes it was verified that GNS inhibits the oxidative degradation of PHBV matrix.  相似文献   
485.
The use of petroleum-derived products should be avoided regarding the principles of green and sustainable chemistry. The work reported herein, is aimed at the liquefaction of pine shavings for the production of an environmentally-friendly polyol suitable to be used in the formulations of sprayable polyurethane foams. The biopolyols were obtained in high yield and were used to replace those derived from fossil sources, to produce more “greener” polyurethane foams and therefore, less dependent on petroleum sources, since the polyol component was substituted by products resulting from biomass liquefaction. The partial and fully exchange of the polyols was accomplished, and the results compared with a reference foam. The foams were afterward, chemical, physical, morphological, and mechanically characterized. The complete replacement of polyether polyol and polyol polyester has presented some similar characteristics as that used as a reference, validating that the path chosen for the development of more sustainable materials is on the right track for the contribution to a cleaner world.  相似文献   
486.
Here, the influence of graphene as a coating on the biodegradation process for two different polymers is investigated, poly(butylene adipate-co-terephthalate) (PBAT) (biodegradable) and low-density polyethylene (LDPE) (non-biodegradable). Chemical vapor deposition graphene was transferred to the surface of two types of polymers using the Direct Dry Transfer technique. Polymer films, coated and uncoated with graphene, were buried in a maturated soil for up to 180 days. The films were analyzed before and after exposure to microorganisms in order to obtain information about the integrity of the graphene (Raman Spectroscopy), the biodegradation mechanism of the polymer (molecular weight and loss of weight), and surface changes of the films (atomic force microscopy and contact angle). The results prove that the graphene coating acted as a material to control the biodegradation process the PBAT underwent, while the LDPE covered by graphene only had changes in the surface properties of the film due to the accumulation of solid particles. Polymer films coated with graphene may allow the production of a material that can control the microbiological degradation, opening new possibilities in biodegradable polymer packaging. Regarding the possibility of graphene functionalization, the coating can also be selective for specific microorganisms attached to the surface.  相似文献   
487.
Animal welfare involves societal and human values, ethical concerns and moral considerations since it incorporates the belief of what is right or what is wrong in animal treatment and care. This paper aims to ascertain whether the different dimensions of individual attitudes toward animal welfare in food choices may be characterized by general human values, as identified by Schwartz. For this purpose, an EU-wide survey was carried out, covering almost 2500 nationally representative individuals from five European countries. Compared with the previous literature this study shows a twofold novelty: (1) it develops a general framework to link individual enduring beliefs and attitudes toward animal welfare attributes in food choices; (2) the framework is analyzed within a broad-based cross-country study. Our empirical results prove that human values related to self-transcendence are strongly associated to overall animal welfare attitudes and especially to those explicitly related to food choices, while values related to the spheres of self-enhancement and conservatism are significantly associated to less sensitive attitudes to animal welfare. Moreover, our results appear to indicate that a determinant of animal welfarism in food choices is potentially associated to individual concerns regarding food safety issues.  相似文献   
488.
The leather industry (tanneries) generates high amounts of toxic wastes, including solid and liquid effluents that are rich in organic matter and mineral content. Vermicomposting was studied as an alternative method of treating the wastes from tanneries. Vermicompost was produced from the following tannery residues: tanned chips of wet-blue leather, sludge from a liquid residue treatment station, and a mixture of both. Five hundred earthworms (Eisenia fetida) were added to each barrel. During the following 135 days the following parameters were evaluated: pH, total organic carbon (TOC), organic matter (OM), cation exchange capacity (CEC), C:N ratio, and chromium content as Cr (III) and Cr (VI). The results for pH, TOC and OM contents showed decreases in their values during the composting process, whereas values for CEC and total nitrogen rose, indicating that the vermicompost reached maturity. For chromium, at 135 days, all values of Cr (VI) were below the detectable level. Therefore, the Cr (VI) content had probably been biologically transformed into Cr (III), confirming the use of this technique as an advanced biological treatment. The study reinforces the idea that vermicomposting could be introduced as an effective technology for the treatment of industrial tannery waste and the production of agricultural inputs.  相似文献   
489.
The ecotoxic effects of carbaryl (carbamate insecticide) were investigated with a battery of four aquatic bioassays. The nominal effective concentrations immobilizing 50% of Daphnia magna (EC50) after 24 and 48 h were 12.76 and 7.47 µg L?1, respectively. After 21 days of exposure of D. magna, LOECs (lowest observed effect concentrations) for cumulative molts and the number of neonates per surviving adult were observed at carbaryl concentration of 0.4 µg L?1. An increase of embryo deformities (curved or unextended shell spines) was observed at 1.8 and 3.7 µg L?1, revealing that carbaryl could act as an endocrine disruptor in D. magna. Other bioassays of the tested battery were less sensitive: the IC50-72h and IC10-72h of the algae Pseudokirchneriella subcapitata were 5.96 and 2.87 mg L?1, respectively. The LC50-6d of the ostracod Heterocypris incongruens was 4.84 mg L?1. A growth inhibition of H. incongruens was registered after carbaryl exposure and the IC20-6d was 1.29 mg L?1. Our results suggest that the daphnid test sensitivity was better than other used tests. Moreover, carbaryl has harmful and toxic effects on tested species because it acts at low concentrations on diverse life history traits of species and induce embryo deformities in crustaceans.  相似文献   
490.
The increase use of pharmaceutical compounds in veterinary practice and human population results in the ubiquitous presence of these compounds in aquatic ecosystems. Because pharmaceuticals are highly bioactive, there is concern about their toxicological effects in aquatic organisms. Therefore, the aim of this study was to assess the effects of an effluent from a psychiatric hospital (containing a complex mixture of 25 pharmaceutical compounds from eleven therapeutic classes) on the freshwater clam Corbicula fluminea using a proteomic approach. The exposure of C. fluminea to this complex effluent containing anxiolytics, analgesics, lipid regulators, beta blockers, antidepressants, antiepileptics, antihistamines, antihypertensives, antiplatelets and antiarrhythmics induced protein changes after 1 day of exposure in clam gills and digestive gland more evident in the digestive gland. These changes included increase in the abundance of proteins associated with structural (actin and tubulin), cellular functions (calreticulin, proliferating cell nuclear antigen (PCNA), T complex protein 1 (TCP1)) and metabolism (aldehyde dehydrogenase (ALDH), alcohol dehydrogenase, 6 phosphogluconate dehydrogenase). Results from this study indicate that calreticulin, PCNA, ALDH and alcohol dehydrogenase in the digestive gland and T complex protein 1 (TCP1)) and 6 phosphogluconate dehydrogenase in the gills represent useful biomarkers for the ecotoxicological characterization of psychiatric hospital effluents in this species.  相似文献   
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