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31.
A. V. Galkin 《Biophysics》2008,53(1):87-88
This is a comment on the paper by Pyatygin in this issue [Biophysics 53(1), 81–86 (2008)], indicating some points that should be clarified to comprehensively assess the apparent diversity of plant electrical signaling. 相似文献
32.
Recycling of aluminum can in terms of Life Cycle Inventory (LCI) 总被引:1,自引:0,他引:1
Jozeti Barbutti Gatti Guilherme de Castilho Queiroz Eloísa Elena Corrêa Garcia 《The International Journal of Life Cycle Assessment》2008,13(3):219-225
Background, Aims and Scope Life Cycle Assessment is a technique for evaluating the environmental performance of a given product by: identifying and quantifying
the energy and raw materials used in its manufacturing process, as well as the emissions of pollutants to water, soil, and
air inherent in this production, use and disposal, and evaluating the environmental impact associated with the use of energy
and materials and the emissions of pollutants, thus identifying opportunities to improve the system in order to optimize the
environmental performance of the product. CETEA (Packaging Technology Center) has conducted a Life Cycle Assessment — LCA
study of aluminum can with emphasis in life cycle inventory, collecting data for the reference years 2000–2002. The goal of
this paper is to present part of this complete study, focusing the influence of aluminium recycling rate on the Life Cycle
Inventory (LCI) of aluminum beverage cans in Brazil.
Methods The adopted methodology was based on the recommendations of SETAC — Society of Environmental Toxicology and Chemistry and
the ISO 14040 Standard, approved by the Sub-Committee 05 of the Environmental Administration Technical Committee, TC-207,
from ISO — INTERNATIONAL ORGANIZATION FOR STANDARDIZATION [1,2]. Data storage and modeling were performed by employing the
PIRA Environmental Management System — PEMS [3].
Results Taking into account the impact categories adopted in this study, it has been shown that recycling helps to improve the aluminium
can environmental profile measured as LCI data.
Discussion For the transformed aluminium products, the recycling rate affects the values of the environmental parameters inventoried,
but not in the same proportion, since the contribution of other stages of the product system life cycle and the recycling
process remain unchanged, including the yield of this process. In general, the recycling balance is always positive due to
the importance of the stages that precede the packaging production and the problem of increasing the municipal waste volume.
Conclusions The advantages of the recycling are obviously concentrated on the inventoried parameters related to the primary aluminum production
and to the package disposal. The verified benefits of the recycling increase with the recycling rate enhancement. However,
the effects on the inventory do not have the same magnitude of the recycling rate. This happens due to the relative contributions
of the other life cycle stages, such as the transportation and sheet or can production. In agreement with the presented results,
it is possible to conclude that the aluminum can recycling reduces part of the consumption of natural resources and the emissions
associated to the stages previous to the production of the packaging. The parameters specifically related to the stage of
aluminum production suffer reduction directly proportional to the increase of the recycling rate. In this way, all of the
efforts made to increase the recycling rate will have a positive contribution to the LCI of the aluminum can.
Recommendations It is worth pointing out that LCA studies are iterative and dynamic. The data can always be refined, substituted or complemented
with updated information in order to improve the representativeness of the analyzed sector.
Perspectives From this study, the aluminum sector in Brazil is able to quantify the benefits of future actions for environmental improvement
of the Brazilian aluminum industry, as well as to contribute technically to Environmental Labeling initiatives regarding aluminum
products.
ESS-Submission Editor: Alain Dubreuil (dubreuil@nrcan.gc.ca) 相似文献
33.
内蒙古锡林郭勒盟国家大型煤电基地既是我国经济发展和区域能源安全的重要基地,又是近首都生态重要屏障保障区域,该区域的生态环境建设直接关系到国家生态安全。选取锡林郭勒盟煤电基地为研究对象,以研究区内各大气污染物排放数据为基础,对照大气环境功能区划,研究大气环境容量。首先绘制了各主要污染物的区域空间分布图,结合功能区大气质量标准得到了锡林郭勒盟环境容量和承载力的空间分布结果。在此研究基础上,按不同目标情景(低标准、中等标准、高标准)进行了区域大气环境承载力的预测,分析了各区域的环境保护对策。为锡盟国家煤电基地建设和生态保护及区域可持续发展提供科学依据。 相似文献
34.
生物静电效应的利用与开发 总被引:6,自引:0,他引:6
韩德恩 《氨基酸和生物资源》2002,24(2):26-30
21世纪自然科学的发展 ,需要生命科学与物理科学 (含物理学、化学和数学 )的交叉渗透 ,生物静电效应的利用与开发是生物物理工程的重要组成部分 ,有着光辉灿烂的前景 相似文献
35.
Klausner has hypothesized that female-headed households are less efficient in the use of energy than male-headed households because they are less disciplined and ordered. The present study used multivariate analyses to determine whether female-headed households were less efficient in the use of electrical energy than male-headed households in a representative sample of 4638 Anglo, Spanish-speaking, and black homeowning Texas households. The results indicated that, after controlling for the effects of other variables known to affect the use of electricity, sex of household head had nostatistically significant independent effect on electricity consumption in any ethnic or marital status group. The authors compare their results to those obtained by Klausner and discuss implications for social organizational theory of household energy consumption. 相似文献
36.
目的:探讨应用钛夹预防高频电切除胃肠道隆起性病变后迟发性出血的效果。方法:对72例77枚胃肠道隆起性病变行高频电切除后应用钛夹钳夹残蒂或创面,观察术后消化道出血情况。结果:平均随访30天,所有患者术后均未出现消化道出血。结论:应用钛夹能有效预防高频电切除胃肠道隆起性病变后迟发性出血。 相似文献
37.
高频电对感染根管消毒作用的初步实验研究 总被引:2,自引:1,他引:1
目的:初步验证高频电对感染根管是否具有较理想的消毒作用,并且与氢氧化钙药尖的消毒作用进行初步比较分析。方法:本实验制作10只家兔40颗门齿的感染根管动物模型,其中20颗用高频电消毒为实验组。20颗用氢氧化钙药尖消毒为对照组,消毒前后分别作需氧菌和厌氧菌培养并比较其消毒效果。结果:消毒前实验组和对照组各20个根管的需氧及厌氧菌培养全部阳性。实验组消毒后需氧菌3个阳性根管、厌氧菌2个阳性根管,消毒前后对需氧和厌氧菌杀灭作用的差异均具有极显著性(P<0.005)。对照组消毒后需氧菌13个阳性根管消毒作用的差异有显著性(P<0.05)。对照组消毒后厌氧菌11个阳性根管消毒作用的差异有极显著性(P<0.005)。实验组和对照组分别对需氧和厌氧2个菌种之间消毒作用的差异均无显著性(P>0.05)。实验组和对照组对需氧菌的消毒作用和对厌氧菌的消毒作用的组间差异均具有极显著性(P<0.005)。结论:高频电对感染根管内容物的消毒作用优于氢氧化钙药尖,具有临床应用的可行性。值得进一步研究。 相似文献
38.
Sung T. Oh Jung Rae Kim Giuliano C. Premier Tae Ho Lee Changwon Kim William T. Sloan 《Biotechnology advances》2010
The need for cost-effective low-energy wastewater treatment has never been greater. Clean water for our expanding and predominantly urban global population will be expensive to deliver, eats into our diminishing carbon-based energy reserves and consequently contributes to green house gases in the atmosphere and climate change. Thus every potential cost and energy cutting measure for wastewater treatment should be explored. Microbial fuel cells (MFCs) could potentially yield such savings but, to achieve this, requires significant advances in our understanding in a few critical areas and in our designs of the overall systems. Here we review the research which might accelerate our progress towards sustainable wastewater treatment using MFCs: system control and modelling and the understanding of the ecology of the microbial communities that catalyse the generation of electricity. 相似文献
39.
Chaochao Li 《Critical reviews in biotechnology》2013,33(8):1015-1030
AbstractVarious new energy technologies have been developed to reduce reliance on fossil fuels. The bioelectrochemical system (BES), an integrated microbial–electrochemical energy conversion process, is projected to be a sustainable and environmentally friendly energy technology. However, low power density is still one of the main limiting factors restricting the practical application of BESs. To enhance power output, functional group modification on anode surfaces has been primarily developed to improve the bioelectrochemical performances of BESs in terms of startup, power density, chemical oxygen demand (COD) removal and coulombic efficiency (CE). This modification could change the anode surface characteristics: roughness, hydrophobicity, biocompatibility, chemical bonding and electrochemically active surface area. This will facilitate bacterial adhesion, biofilm formation and extracellular electron transfer (EET). Additionally, some antibacterial functional groups are applied on air cathodes in order to suppress aerobic biofilms and enhance cathodic oxygen reduction reactions (ORRs). Various modification strategies such as: soaking, heat treatment and plasma modification have been reported to introduce functional groups typically as O-, N- and S-containing groups. In this review, the effects of anode functional groups on electroactive bacteria through the whole biofilm formation process are summarized. In addition, the application of those modification technologies to improve bioelectricity generation, resource recovery, bioelectrochemical analysis and the production of value-added chemicals and biofuels is also discussed. Accordingly, this review aims to help scientists select the most appropriate functional groups and up-to-date methods to improve biofilm formation. 相似文献
40.
G. Venkatesh 《Journal of Industrial Ecology》2013,17(3):472-481
The focus of urban water system metabolism studies has, by and large, been restricted to what comes under the domain of the urban water utilities: water treatment and supply, and wastewater collection, treatment, and disposal. The material and energy flows both necessitated and facilitated by the supply of treated water to households—the water demand subsystem—are by no means negligible. This article studies the key flows into households associated with water consumption and the environmental impacts related to the same for India as a whole. Electricity consumption in washing machines and water heaters contributes the most to almost all the 13 environmental impact categories considered. This is easily explained by the fossil fuel heaviness of the Indian mix (>60%). Soaps contribute the most to terrestrial eco‐toxicity and malodorous air. In India, on a national scale, all the environmental impact categories deserve attention. The absolute consumption of electricity, soaps, and detergents, and the demand for home appliances will increase in the years to come. 相似文献