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91.
Robert D. De Kleine Gregory A. Keoleian Shelie A. Miller Andrew Burnham John L. Sullivan 《Journal of Industrial Ecology》2014,18(3):356-365
The Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model developed by Argonne National Laboratory quantifies the life cycle energy consumption and air emissions resulting from the production and use of light‐duty vehicles in the United States. GREET is comprised of two components: GREET 1 represents the fuel cycle of various energy carriers, including automotive fuels, and GREET 2 represents the vehicle cycle, which accounts for the production of vehicles and their constituent materials. The GREET model was updated in 2012 and now includes higher‐resolution material processing and transformation data. This study evaluated how model updates influence material and vehicle life cycle results. First, new primary energy demand and greenhouse gas (GHG) emissions results from GREET 2 for steel, aluminum, and plastics resins are compared herein with those from the previous version of the model as well as industrial results. A part of the comparison is a discussion about causes of differences between results. Included in this discussion is an assessment of the impact of the new material production data on vehicle life cycle results for conventional internal combustion engine (ICE) vehicles by comparing the energy and GHG emission values in the updated and previous versions of GREET 2. Finally, results from a sensitivity analysis are presented for identifying life cycle parameters that most affect vehicle life cycle estimates. 相似文献
92.
Different seafood products based on Peruvian anchoveta (Engraulis ringens) fisheries and freshwater aquaculture of trout (Oncorhynchus mykiss), tilapia (Oreochromis spp.) and black pacu (Colossoma macropomum), contribute at different scales to the socio-economic development, environmental degradation and nutrition of the Peruvian population. Various indicators have been used in the literature to assess the performance of these industries regarding different aspects of sustainability, notably their socio-economic performance. In this study, a novel set of indicators is proposed to evaluate the sustainability performance of these industries in Peru, based on life cycle assessment (LCA) and nutritional profiling, as well as on energy and socio-economic assessment approaches. The emphasis is put on the potential of different products to contribute to improving the nutrition of the Peruvian population in an energy-efficient, environmentally friendly and socio-economically sound way. The set of indicators includes biotic resource use (BRU), cumulative energy demand (CED), energy return on investment (EROI), production costs, gross profit generation, added value, and nutritional profile in terms of vitamins, minerals and essential fatty acids; as well as a number of life cycle impact assessment indicators commonly used in seafood studies, and some recently proposed indicators of resource status (measuring the impacts of fish biomass removal at the species and ecosystem levels). Results suggest that more energy-intensive/highly processed products (cured and canned anchoveta products) represent a higher burden, in terms of environmental impact, than less energy-intensive products (salted and frozen anchoveta products, semi-intensive aquaculture products). This result is confirmed when comparing all products regarding their industrial-to-nutritional energy ratio. Regarding the other attributes analysed, the scoring shows that salted and frozen anchoveta products generate fewer jobs and lower gross profit than canned and cured, while aquaculture products maximise them. Overall, it was concluded that less energy-intensive industries (anchoveta freezing and salting) are the least environmentally impacting but also the least economically interesting products, yet delivering higher nutritional value. Aquaculture products maximise gross profit and job creation, with lower energy efficiency and nutritional values. The proposed set of sustainability indicators fulfilled its goal in providing a multi-criteria assessment of anchoveta direct human consumption and freshwater aquaculture products. As often the case, there is no ideal product and the best trade-off must be sought when making decision regarding fisheries and seafood policy. No threshold for performance of the different indicators is offered, because the goal of the comparison is to contrast the relative performance among products, not of products against reference values. 相似文献
93.
Fabiano Jares Contesini Ricardo Rodrigues de Melo Hélia Harumi Sato 《Critical reviews in biotechnology》2018,38(3):321-334
Proteases have a broad range of applications in industrial processes and products and are representative of most worldwide enzyme sales. The genus Bacillus is probably the most important bacterial source of proteases and is capable of producing high yields of neutral and alkaline proteolytic enzymes with remarkable properties, such as high stability towards extreme temperatures, pH, organic solvents, detergents and oxidizing compounds. Therefore, several strategies have been developed for the cost-effective production of Bacillus proteases, including optimization of the fermentation parameters. Moreover, there are many studies on the use of low-cost substrates for submerged and solid state fermentation. Other alternatives include genetic tools such as protein engineering in order to obtain more active and stable proteases and strain engineering to better secrete recombinant proteases from Bacillus through homologous and heterologous protein expression. There has been extensive research on proteases because of the broad number of applications for these enzymes, such as in detergent formulations for the removal of blood stains from fabrics, production of bioactive peptides, food processing, enantioselective reactions, and dehairing of skins. Moreover, many commercial proteases have been characterized and purified from different Bacillus species. Therefore, this review highlights the production, purification, characterization, and application of proteases from a number of Bacillus species. 相似文献
94.
Based on literature review, firstly, the work analyzed the necessity and main features of venture capital promoting green innovation of entity industry. Greenization of venture capital was the key to promote green innovation of entity industry. Secondly, the mechanism that venture capital promoted green innovation of entity industry was analyzed through model construction. The results showed that construction of ecological civilization as well as market competition and regulations were preconditions of transforming ordinary venture capital into green venture capital; they were also the precondition of venture capital promoting green innovation of entity industry. Thirdly, theoretical and empirical studies were conducted on effects of venture capital for green innovation of entity industry. Recommendations were proposed for venture capital to promote green innovation of entity industry. Empirical studies showed that venture capital could more effectively enhance the green innovation capacity of Chinese entity industry than bank loans. To exert the role of venture capital in green innovation of entity industry, the development of venture capital should be accelerated in a larger scale. Meanwhile, Chinese venture capital industry should be promoted for green transformation, thus more venture capital can be transformed into green venture capital. 相似文献
95.
Vehicles and Critical Raw Materials: A Sustainability Assessment Using Thermodynamic Rarity
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Abel Ortego Alicia Valero Antonio Valero Eliette Restrepo 《Journal of Industrial Ecology》2018,22(5):1005-1015
The changing material composition of cars represents a challenge for future recycling of end‐of‐life vehicles (ELVs). Particularly, as current recycling targets are based solely on mass, critical metals increasingly used in cars might be lost during recycling processes, due to their small mass compared to bulk metals such as Fe and Al. We investigate a complementary indicator to material value in passenger vehicles based on exergy. The indicator is called thermodynamic rarity and represents the exergy cost (GJ) needed for producing a given material from bare rock to the market. According to our results, the thermodynamic rarity of critical metals used in cars, in most cases, supersedes that of the bulk metals that are the current focus of ELV recycling. While Fe, Al, and Cu account for more than 90% of the car's metal content, they only represent 60% of the total rarity of a car. In contrast, while Mo, Co, Nb, and Ni account for less than 1% of the car's metal content, their contribution to the car's rarity is larger than 7%. Rarity increases with the electrification level due to the greater amount of critical metals used; specifically, due to an increased use of (1) Al alloys are mainly used in the car's body‐in‐white of electric cars for light‐weighting purposes, (2) Cu in car electronics, and (3) Co, Li, Ni, and rare earth metals (La, Nd, and Pr) in Li‐ion and NiMH batteries. 相似文献
96.
Data from the Workplace Environmental Monitoring Program was used to evaluate the concentrations and risk of occupational exposure to styrene in different industries to identify which industries should be prioritized for styrene exposure management. Risk assessments were conducted for the five industries with several workplaces that mostly use styrene: motor vehicle and motorcycle maintenance and repair services, other chemical product manufacturing, ship and boat building, basic chemical manufacturing, and plastic products manufacturing. The highest central tendency exposure was found in the plastic products manufacturing industry (10.14 mg/m3). In addition, the hazard quotient (HQ) for central tendency exposure exceeded 1 only in the plastic products manufacturing industry. Almost two-thirds (62.2%) of workplaces in the plastic products manufacturing industry have an HQ exceeding 1. We conclude that workers in the plastic products manufacturing industry are at the highest risk for styrene exposure, and those in motor vehicle and motorcycle maintenance and repair service and basic chemical manufacturing are at the lowest risk. These results show that styrene exposure could be most effectively managed by prioritizing control measures in the plastic products manufacturing industry. 相似文献
97.
食用菌跻身我国第五大农作物,我国已经成为名副其实的食药用菌大国。本文对近十年来食药用菌重要种类名称变更、人工培植或栽培技术的突破和基因组学研究的进展进行了综述。随着分子系统学研究的深入,灵芝、黑木耳、毛木耳、桑黄等重要种类的名称得到更正和完善;冬虫夏草、羊肚菌、暗褐网柄牛肝菌等难栽培种类在全世界范围内首次实现人工栽培;大多数常见食药用菌种类完成了基因组解析。分析了分类和系统发育研究、生物学研究、组学研究与食药用菌产业发展的关系,基础研究促进食药用菌产业发展,同时产业发展为基础研究提出更多的科学问题。 相似文献
98.
Smart factories have been widely adopted as a new manufacturing paradigm, in which the state‐of‐the‐art technologies are introduced to improve relevant processes. Yet, whether smart factories affect the environmental performance remains unknown. In this article, we examine the environmental performance of a smart refrigerator factory by comparing the environmental impacts of its product to a similar model that is produced in a traditional fashion. This article quantifies and verifies the theoretically predicted impacts of this smart factory on the individual processes. Though the overall differences in the two models are quite minor, we find that this smart factory can notably reduce the values of most impact categories associated with the parts and refrigerator production; the reduction in the value of climate change is 33%. Owing to higher material efficiency—raw material savings in this smart factory contributes to the greatest reductions in most categorized impacts—the contribution to the reduction of climate change is 39%. Yet, all categorized impacts of procurement and delivery are increased due to product personalization and direct delivery. The results of sensitivity analysis show that promoting product modularity, adopting clean energy such as wind power can further improve the environmental performance of the selected refrigerator. The introduction of auxiliary equipment and systems slightly increases the value of each category; yet their impacts are negligible compared to their benefits as facilitating production efficiency. Based on the quantitative results, recommendations are given to improve the environmental performance of smart factory, including optimizing current strategies and promoting horizontal and end‐to‐end integration. 相似文献
99.
黄土丘陵区农业生态系统产业结构分析 总被引:8,自引:0,他引:8
以安塞纸坊沟小流域为例,在对黄土丘陵区农业生态系统产业结构的动态分析的基础上,为了反映产业结构中各产业之间的变化趋势以及整体结构的波动情况,选取产业优势度和产业结构变异性为指标,对农业生态系统的产业结构可持续发展进行评价。结果表明在1980~2001年期间该流域的结构优势度在0.687~0.958之间波动,从1997年结构优势度开始下降;在1980~1995年间结构变异性缩小,在1996~2001年结构变异性有上升趋势,且上升平缓。表明流域的产业结构仍在不断调整过程中。 相似文献
100.
食用菌产业专业化人才培养模式的探索 总被引:1,自引:0,他引:1
针对食用菌产业高素质专业人才培养目标的要求,从专业培养目标的导向性、课程设置的滞后性、实训教学的缺失性、教学方式的被动性等方面分析了食用菌专业人才培养模式存在的问题。以华南农业大学食用菌专业人才培养模式为例,从食用菌产业对专业人才培养目标的定位与特色、专业理论与实践课程设置的优化创新、教学方式与考核方式的优化创新等方面,探究食用菌产业专业人才的培养模式,为进一步完善现有的人才培养方案、推动人才培养模式的改革提供一定的参考。 相似文献