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One engine that drives the United States’ economic growth is an ever-increasing demand for manufactured products, both at home and abroad. This increase has created a major concern for the environment in terms of disposing used goods and ensuring that these products are safe. As environmental concerns grow, however, renewable resources are gaining increasing attention, especially as industrial ecology and product biodegradability gain importance. Added to this, biological materials are increasingly being utilized to replace traditional materials in manufacturing. To aid both educators as well as researchers, this paper examines several considerations that are essential for manufacturing plastic products that contain biomaterials. These include the selection of materials, the selection of manufacturing processes, manufacturing costs, and the quality of final products. Additionally, several standard methods that are commonly used for the determination of mechanical and physical properties are compiled; thus this paper should be a useful resource for both educators and researchers. The trends discussed here and their implications are critical for those involved in manufacturing, because contrary to conventional wisdom, simultaneously meeting the material production needs of our society, as well as that of the environment are not mutually-exclusive. 相似文献
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Hongyu Liu Hu Zhang Shan Chen Dongbo Liu Hongmei Xia 《Journal of Polymers and the Environment》2006,14(4):419-426
An extracellular poly (β-hydroxybutyrate) (PHB) depolymerase was purified from a Penicillium sp. DS9701-09a by centrifugation, ultrafiltration, precipitation and gel filtration chromatography. The specific activity of the purified enzyme was 37.9-folds higher than that of the culture supernatant and the recovery yield was 11.8%. The PHB deploymerase molecular mass was 44.8 kDa from analysis of both Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Matrix-assisted laser desorption-time-of-flight (MALDI-TOF) mass spectrometer. The isoelectric point of 6.7 for the enzyme was determined by a two-dimensional electrophoresis. The optimum enzyme activity was observed at a temperature of 50 °C and pH 5.0. The apparent K
m of the enzyme was found to be 1.35 mg/mL. The PHB depolymerase consisted of 16 kinds of normal amino acids. The secondary structure of the enzyme was determined by CD spectrum. α-helix and β-turn were found to be 66% and 34% for the enzyme without ammonium sulphite. Chemical inhibition on the PHB depolymerase activity was examined and EDTA was found to have a significantly inhibitory effect. 相似文献
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城市生活垃圾焚烧灰渣及其性质分析 总被引:25,自引:0,他引:25
2002年,上海有2座生活垃圾焚烧厂将点火运动。每年将产生约18万t左右的焚烧灰渣。在决定灰渣的最终处理处置方案前,应对焚烧灰渣的性质有全面的了解。详细介绍了国外城市生活垃圾焚烧灰渣甚至生位置的不同分类,并介绍了各类灰渣的物理化学性质和工程性质,以及其重金属的浸出特征。对灰渣处理放置或有效利用时需注意的问题作了分析。 相似文献
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山梨醇型凝油剂的制备与性能 总被引:4,自引:0,他引:4
介绍了山梨醇型凝油剂的制备方法,以及其胶凝轻质渍及类油物质的性质。结果表明,此类凝油剂对汽油,柴油,机油以及基苯及苯系有机溶剂等的去除率达90%以上。经生物毒性试验表明,不会对水中鱼类产生毒性效应,凝油后油凝体硬度可达3.9×10^4-9.8×10^4Pa。可用于各种轻质油及类油物质泄漏等突发性事故的应急处理。 相似文献
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Ge H.Zhang D.Wu S.Qiu Y.Zhang G. 《应用与环境生物学报》2018,(4):853-859
To investigate the underlying mechanism of the unique phase transition behavior of SpyCatcher-ELPs40 (C-E) and the influence of the oligomerization domain on the phase transition of C-E, we constructed a non-covalent three-armed star oligomerization of C-E-F and E-F by fusing the Foldon (F) domain with SpyCatcher-ELPs40 (C-E) and ELPs40 (E). Results showed that the phase transition temperature of ELPs40 fused with Foldon was higher than that of ELPs120, whereas it was lower than those of ELPs40 and the SpyTag/SpyCatcher-mediated covalent three-armed elastin-like polypeptides (ELPs). This proved that the topology of ELPs could affect their phase transition behaviors. The phase transition temperature of C-E-F was 28.8 ℃ and 35.6 ℃ higher than those of C-E and ELPs40, respectively, although C-E-F had a similar sequence with C-E and ELPs40. When the concentration of NaCl was 0.8 mol/L, the differences in the phase transition temperatures were 41.2 ℃ and 47.1, respectively. We could only observe the phase transition of C-E-F in the Na2CO3 solution with high concentration (≥ 0.7 mol/ L); however, the phase transition could be clearly detected in the Na2SO4 solution, even when the concentration of Na2SO4 was very low. This result was obviously inconsistent with the Hofmeister series. This is the first report of non-linear ELPs that has shown this unique phase transition behavior. The possible reason was related to the charges distributed on the solvent accessible surface and the oligomeric state of C-E-F triggered by the Foldon domain. © 2018 Science Press. All rights reserved. 相似文献
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三峡库区城市生活垃圾的理化性质研究 总被引:2,自引:0,他引:2
对三峡库区重点区县的城市生活垃圾堆场进行了采样分析,研究了堆存垃圾的组分;氮、磷、钾、重金属等指标;热值、含水率等理化性质;可生物降解度(COD)等,分析了垃圾对环境的影响,为库区城市生活垃圾的处理处置提供了技术支持。 相似文献