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721.
Umberto Iemma Fabio Pisi Vitagliano 《International Journal of Sustainable Engineering》2018,11(2):122-134
The current work deals with multi-objective optimisations including financial merit factors in the multi-disciplinary conceptual design of a commercial aircraft with a specific focus on noise social cost. The results of optimisations using financial and performance-oriented objective functions have been analysed and combined in a multi-objective optimisation problem using a three-dimensional objective vector. The main novelty of the present work is the analysis of social cost noise fees effectiveness integrated in financial models embracing a wider group of stakeholders’ interests. The foundations of this research lie on the air traffic increase envisaged in the next decades and the contextual growth of the urban areas nearby airport facilities. This scenario requires the aeronautical industry to handle the environment challenge taking into account all the social and economic effects. Indeed, the consolidated technology has approached a saturation point, therefore breakthrough concepts and configurations are mandatory. This matter is addressed as a highly multi-disciplinary problem within conceptual design framework. The financial model proposed is shown to highlight the need of appropriate noise fees as instruments to push all stakeholders towards a technology radical renewal and encourage the aeronautical industry towards a shared strategy in the development of an eco-friendly commercial aviation system. 相似文献
722.
Diversity of antibiotic resistance genes and encoding ribosomal protection proteins gene in livestock waste polluted environment 总被引:1,自引:0,他引:1
Chunyan Li Cheng Jiang Zhiyang Wu Xuejiao An Hailan Wang 《Journal of environmental science and health. Part. B》2018,53(7):423-433
The rapid development and increase of antibiotic resistance are global phenomena resulting from the extensive use of antibiotics in human clinics and animal feeding operations. Antibiotics can promote the occurrence of antibiotic resistance genes (ARGs), which can be transferred horizontally to humans and animals through water and the food chain. In this study, the presence and abundance of ARGs in livestock waste was monitored by quantitative PCR. A diverse set of bacteria and tetracycline resistance genes encoding ribosomal protection proteins (RPPs) from three livestock farms and a river were analyzed through denaturing gradient gel electrophoresis (DGGE). The abundance of sul(I) was 103 to 105 orders of magnitude higher than that of sul(II). Among 11 tet-ARGs, the most abundant was tet(O). The results regarding bacterial diversity indicated that the presence of antibiotics might have an evident impact on bacterial diversity at every site, particularly at the investigated swine producer. The effect of livestock waste on the bacterial diversity of soil was stronger than that of water. Furthermore, a sequencing analysis showed that tet(M) exhibited two genotypes, while the other RPPs-encoding genes exhibited at least three genotypes. This study showed that various ARGs and RPPs-encoding genes are particularly widespread among livestock. 相似文献
723.
为了考察水力停留时间(HRT)对炭纤维载体固定床厌氧反应器运行效果的影响,在进水COD分别为20 000~25 000 mg/L和40 000~45 000 mg/L2个浓度范围下,研究了不同HRT对反应器运行效果的影响。结果表明,通过HRT的调整,在达到相同有机负荷(OLR)下,进水COD为20 000~25 000 mg/L的COD去除率和产气量,明显比进水COD为40 000~45 000 mg/L的运行效果好;进水COD为20 000~25 000 mg/L,HRT为14 h,相应的OLR为41.09 kgCOD/(m3.d)时,COD去除率仍然维持在68%以上,沼气容积产气率达到14.55 m3/(m3.d)。炭纤维载体固定床厌氧反应器具有较高的COD去除率、产气效率以及抵抗低pH、高负荷冲击的能力,运行过程中没有发生反应器堵塞的现象。 相似文献
724.
石膏浆液旋流器的分离性能实验研究 总被引:1,自引:1,他引:0
通过理论分析及工程经验对石灰石/石膏法烟气脱硫工艺中石膏浆液脱水系统的旋流器进行优化设计,在与工业实际相近的操作条件下,优选出了一根综合性能较好的旋流器。考察了该旋流器的压力、流量与分离效率之间相互关系,与常规石膏浆液旋流器的分级效率进行了比较,确定了最佳操作条件。结果表明,旋流器的进口流量随着进出口压力差的增大而增大,分离效率随着流量增加先上升后下降。在进口硫石膏颗粒平均粒径为24μm,流量为11.8~14.8 m3/h时,分离效率在85%以上,底流出口10μm、15μm以下的颗粒分别占底流出口颗粒总体积的1%、10%左右,起到了很明显的分级浓缩作用,分离性能也优于常规使用的石膏浆液旋流器。 相似文献
725.
726.
介质阻挡放电联合催化臭氧化降解甲苯 总被引:4,自引:2,他引:2
采用介质阻挡放电区后结合MnOx/Al2O3/发泡镍去除甲苯,考察甲苯进气方式、臭氧产生方法及湿度对甲苯与O3同时去除的影响。结果表明,O3是等离子体区后催化降解甲苯的主要物种,介质阻挡放电联合催化臭氧化可实现甲苯及O3的同时高效去除。输入电压为9.0 kV时,甲苯的去除效率达92.8%,在80 min内O3的去除效率维持在99%以上。水蒸气对催化剂催化分解臭氧的活性没有直接的影响,O3浓度较高时湿度对甲苯降解效率的影响很小。GC-MS分析结果表明,甲苯降解的主要气相副产物有烷烃、酸、酮和含苯环有机物,提出了甲苯的降解途径。 相似文献
727.
728.
729.
采用生命周期评价法研究比较了北京和上海两地纸塑铝复合包装处置阶段的环境影响。通过现场和资料调研的方式获得此阶段的能量物质的输入输出和环境外排数据。结果表明:北京和上海两地纸塑铝复合包装处置阶段的环境影响潜值分别为-0.428 Pt和9.776 Pt,其主要集中在气候变化、土地占用和无机物对健康的损害三方面;每提高10%的回收率,其环境影响潜值北京和上海可分别降低5.446 Pt和5.799 Pt;上海地区纸塑铝复合包装处置阶段对环境的影响在任何同回收率的情况都要高于北京地区,其主要原因是上海地区填埋产生的温室气体释放量过大和再生企业距离打包点较远。 相似文献
730.
Yamaguchi N Nakano M Takamatsu R Tanida H 《Journal of environmental radioactivity》2010,101(6):451-9983
The transformation of inorganic iodine (I− and IO3−) incubated in soils with varying amounts of organic matter (Andosols from the surface layer of an upland field and forest, as well as Acrisols from surface and subsurface layers of an upland field) was investigated by using the iodine K-edge X-ray absorption near-edge structure (XANES). After 60 d of reaction, both I− and IO3− were transformed into organoiodine in surface soils containing sufficient amounts of organic matter, whereas IO3− remained unchanged in the subsurface soil of Acrisols with low organic matter contents. Transformation of IO3− into organoiodine was not retarded when the microbial activity in soil was reduced by γ-ray irradiation, suggesting that microbial activity was not essential for the transformation of inorganic iodine into organoiodine. Soil organic matter has the ability to transform inorganic iodine into organoiodine. 相似文献