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Karolina Storesund Francine Amon Anne Steen‐Hansen Shayesteh Haghighatpanah Ida Larsson 《火与材料》2021,45(1):181-190
The aim of this exploratory study has been to investigate the fire properties and environmental aspects of different upholstery material combinations, mainly for domestic applications. An analysis of the sustainability and circularity of selected textiles, along with lifecycle assessment, is used to qualitatively evaluate materials from an environmental perspective. The cone calorimeter was the primary tool used to screen 20 different material combinations from a fire performance perspective. It was found that textile covers of conventional fibres such as wool, cotton and polyester, can be improved by blending them with fire resistant speciality fibres. A new three‐dimensional web structure has been examined as an alternative padding material, showing preliminary promising fire properties with regard to ignition time, heat release rates and smoke production. 相似文献
3.
Bioremediation strategies have been applied to clean up petroleum hydrocarbon (PHC) impacted sites. Introducing PHC degrading microorganisms (bioaugmentation) and enhancing the in‐situ nutrients availability (biostimulation) are widely used strategies. These strategies can be combined to lead to a better bioremediation performance. In this work, Pseudomonas fluorescens was isolated from a PHC impacted site. Through a 23 factorial design plan, the effect of various combinations of nitrate, sulphate, and phosphate ions on the PHC bioremediation performance by P. fluorescens was investigated using catechol, an essential metabolic intermediate of BTEX degradation, as the sole carbon source. The maximum specific catechol degradation rate was chosen as the response to evaluate the catechol bioremediation performance. The ANOVA results indicated that the presence of nitrate ions alone lowered the maximum specific catechol degradation rate, which can be explained by the accumulation of nitrites and ammonia during the denitrification process by P. fluorescens. It was noted that dosing sulphate ions alone did not affect the bioremediation performance, which indicates P. fluorescens can grow in a sulphur‐limited environment. In contrast, the presence of sulphate and nitrate ions together can lead to a higher specific catechol degradation rate. This may be caused by the presence of sulphate that can suppress the production of nitrites. The importance of phosphate ions on catechol biodegradation was investigated. The absence of phosphate led to incomplete biodegradation. Introducing phosphate ions can accelerate catechol degradation, which can be explained by the secretion of organic acids. 相似文献
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Aditya Arun Lakshaman Kumar Anirban Chowdhury 《Journal of the American Ceramic Society》2021,104(7):3497-3507
Dense (~97%) CaO-stabilized ZrO2 ceramic was stabilized with minimum (3 mol%) doping (reported to date) and processed via conventional sintering at a low temperature (~1200°C); compositional analysis via X-ray florescence confirmed the CaO doping accuracy. Phase-pure tetragonal structure (characterized via both X-ray diffraction and Raman spectroscopy) along with uniform nanograins (90 nm) of the ceramic ensured the evolution of no monoclinic phase even after vigorous low-temperature degradation experiments (both thermal and hydrothermal aging for 80-100 h). The sintered ceramic recorded a high hardness (~15 GPa); the indentation toughness value was also comparable to a 3 mol% yttria-stabilized zirconia system. The remarkable structure–property correlations in the 3 mol% CaO-stabilized ZrO2 ceramic suggests that the same may be worth examining for suitable future applications (e.g., in dental ceramics). 相似文献
6.
Srinivasan Deepasree Murugesan Arun 《Bulletin of Engineering Geology and the Environment》2022,81(8):1-15
Bulletin of Engineering Geology and the Environment - The pavements of the Beijing Capital International Airport (BCIA), China, where a buried fault zone lies beneath, have undergone continuous... 相似文献
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Lipase production by solid‐state fermentation of olive pomace in tray‐type and pressurized bioreactors 下载免费PDF全文
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Poly(lactic acid) formulations with improved toughness by physical blending with thermoplastic starch 下载免费PDF全文
This work focuses on poly(lactic acid) (PLA) formulations with improved toughness by physical blending with thermoplastic maize starch (TPS) plasticized with aliphatic–aromatic copolyester up to 30 wt %. A noticeable increase in toughness is observed, due to the finely dispersed spherical TPS domains in the PLA matrix. It is worth to note the remarkable increase in the elongation at break that changes from 7% (neat PLA) up to 21.5% for PLA with 30 wt % TPS. The impact‐absorbed energy is markedly improved from the relatively low values of neat PLA (1.6 J m?2) up to more than three times. Although TPS is less thermally stable than PLA due to its plasticizer content, in general, PLA/TPS blends offer good balanced thermal stability. The morphology reveals high immiscibility in PLA/TPS blends, with TPS‐rich domains with an average size of 1 μm, finely dispersed which, in turn, is responsible for the improved toughness. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45751. 相似文献
10.
M. E. Alemán‐Domínguez Z. Ortega A. N. Benítez G. Vilariño‐Feltrer J. A. Gómez‐Tejedor A. Vallés‐Lluch 《应用聚合物科学杂志》2018,135(14)
Carboxymethyl cellulose (CMC) is herein proposed as additive in polycaprolactone (PCL) matrices to obtain composites with tunable hydrophilicity. This composite material can be obtained by compression molding. The thermogravimetric degradation profile, the FTIR spectra, values of the water contact angle (WCA), water and phosphate‐buffered saline uptake values, and the results of a cytotoxicity assessment are presented herein. The concentrations of CMC in the groups of samples are 0, 2, 5, 10, and 20%. The WCA on the prewetted state decreases proportionally to the concentration of the additive. These results evidence the possibility of obtaining a PCL‐based composite with tunable hydrophilicity. Besides, the biological assessment does not reveal any cytotoxic effects. Therefore, the addition of CMC entails an innovative strategy to control the water affinity of PCL in biomedical applications where such feature is required to improve diffusion of biological medium through, or accelerate degradation by hydrolysis. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46134. 相似文献