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51.
Sustainable use of wood may contribute to coping with energy and material resource challenges. The goal of this study is to increase knowledge of the environmental effects of wood use by analyzing the complete value chain of all wooden goods produced or consumed in Switzerland. We start from a material flow analysis of current wood use in Switzerland. Environmental impacts related to the material flows are evaluated using life cycle assessment–based environmental indicators. Regarding climate change, we find an overall average benefit of 0.5 tonnes carbon dioxide equivalent per cubic meter of wood used. High environmental benefits are often achieved when replacing conventional heat production and energy‐consuming materials in construction and furniture. The environmental performance of wood is, however, highly dependent on its use and environmental indicators. To exploit the mitigation potential of wood, we recommend to (1) apply its use where there are high substitution benefits like the replacement of fossil fuels for energy or energy‐intensive building materials, (2) take appropriate measures to minimize negative effects like particulate matter emissions, and (3) keep a systems perspective to weigh effects like substitution and cascading against each other in a comprehensive manner. The results can provide guidance for further in‐depth studies and prospective analyses of wood‐use scenarios.  相似文献   
52.
Aim, Scope and Background  When materials are recycled they are made available for use for several future life cycles and can therefore replace virgin material more than just once. In order to analyse the optimal waste management system for a given material, the authors have analysed the material flows in a life cycle perspective. It is important to distinguish this approach for material flow analysis for a given material from life cycle analysis of products. A product life cycle analysis analyses the product system from cradle to grave, but uses some form of allocation in order to separate the life cycle of one product from another in cases where component materials are recycled. This paper does not address allocation of burdens between different product systems, but rather focuses on methodology for decision making for waste management systems where the optimal waste management system for a given material is analysed. The focus here is the flow of the given material from cradle (raw material extraction) to grave (the material, or its inherent energy, is no longer available for use). The limitation on the number of times materials can be recycled is set by either the recycling rate, or the technical properties of the recycled material. Main Features  This article describes a mathematical geometric progression approach that can be used to expand the system boundaries and allow for recycling a given number of times. Case studies for polyethylene and paperboard are used to illustrate the importance of including these aspects when part of the Goal and Scope for the LCA study is to identify which waste management treatment options are best for a given material. The results and discussion examine the different conclusions that can be reached about which waste management option is most environmentally beneficial when the higher burdens and benefits of recycling several times are taken into account. Results  In order to assess the complete picture of the burdens and benefits arising from recycling the system boundaries must be expanded to allow for recycling many times. A mathematical geometric progression approach manages to take into account the higher burdens and benefits arising from recycling several times. If one compares different waste management systems, e.g. energy recovery with recycling, without expanding the system to include the complete effects of material recycling one can reach a different conclusion about which waste management option is preferred. Conclusions  When the purpose of the study is to compare different waste management options, it is important that the system boundaries are expanded in order to include several recycling loops where this is a physical reality. The equations given in this article can be used to include these recycling loops. The error introduced by not expanding the system boundaries can be significant. This error can be large enough to change the conclusions of a comparative study, such that material recycling followed by incineration is a much better option than waste incineration directly. Recommendations and Outlook  When comparing waste management solutions, where material recycling is a feasible option, it is important to include the relevant number of recycling loops to ensure that the benefits of material recycling are not underestimated. The methodology presented in this article should be used in future comparative studies for strategic decision-making for waste management. The approach should not be used for LCAs for product systems without due care, as this could lead to double counting of the benefits of recycling (depending on the goal and scope of the analysis). For materials where the material cycle is more of a closed loop and one cannot truly say that recycled materials replace virgin materials, a more sophisticated approach will be required, taking into account the fact that recycled materials will only replace a certain proportion of virgin materials.  相似文献   
53.
Förster resonance energy transfer (FRET) microscopy continues to gain increasing interest as a technique for real-time monitoring of biochemical and signaling events in live cells and tissues. Compared to classical biochemical methods, this novel technology is characterized by high temporal and spatial resolution. FRET experiments use various genetically-encoded biosensors which can be expressed and imaged over time in situ or in vivo1-2. Typical biosensors can either report protein-protein interactions by measuring FRET between a fluorophore-tagged pair of proteins or conformational changes in a single protein which harbors donor and acceptor fluorophores interconnected with a binding moiety for a molecule of interest3-4. Bimolecular biosensors for protein-protein interactions include, for example, constructs designed to monitor G-protein activation in cells5, while the unimolecular sensors measuring conformational changes are widely used to image second messengers such as calcium6, cAMP7-8, inositol phosphates9 and cGMP10-11. Here we describe how to build a customized epifluorescence FRET imaging system from single commercially available components and how to control the whole setup using the Micro-Manager freeware. This simple but powerful instrument is designed for routine or more sophisticated FRET measurements in live cells. Acquired images are processed using self-written plug-ins to visualize changes in FRET ratio in real-time during any experiments before being stored in a graphics format compatible with the build-in ImageJ freeware used for subsequent data analysis. This low-cost system is characterized by high flexibility and can be successfully used to monitor various biochemical events and signaling molecules by a plethora of available FRET biosensors in live cells and tissues. As an example, we demonstrate how to use this imaging system to perform real-time monitoring of cAMP in live 293A cells upon stimulation with a β-adrenergic receptor agonist and blocker.  相似文献   
54.
The current study characterizes and analyzes glow curves obtained from phosphate glass doped with different concentrations of lanthanum. Kinetic parameters of the glow curves obtained from beta‐irradiated phosphate glass samples doped with lanthanum were determined using a newly designed deconvoluted software. The obtained results from the analyses indicated that the glow curves of the phosphate glass samples were composed of five overlapping peaks. The activation energies of the five electron traps were located between 0.622 and 1.133 eV. The obtained kinetic parameters were evaluated using the designed software and another two methods and all revealed good agreement. The first three traps displayed non‐first‐order behaviour, while the two deep traps obeyed nearly first‐order kinetics.  相似文献   
55.
56.
美国不同棱型大麦种质资源品质分析   总被引:4,自引:2,他引:4  
对新引进的300份美国大麦种质资源不同棱型间蛋白质、赖氨酸和淀粉含量的鉴定结果分析表明:①二棱大麦蛋白质总体方差与六棱大麦具有极显著的差异,其频率分布分别是以含量12.5%和17.0%为中心的双峰分布,这可能反映了二棱大麦利用上的新特点;淀粉含量二棱大麦显著高于六棱;六棱大麦当蛋白质作为固定变量时,赖氨酸与淀粉的相关性不显著.②提出了促进SPSS统计分析软件在农业科研上的开发应用研究的建议.  相似文献   
57.
利用SPSS软件计算杀虫剂的LC_(50)   总被引:45,自引:1,他引:45  
贾春生 《昆虫知识》2006,43(3):414-417
利用实例和SPSS 130软件上的Probit过程,介绍如何进行LC50计算,并对主要输出结果进行了解释。并通过与其它软件比较,表明应用SPSS软件进行LC50等计算简便、快速、准确。  相似文献   
58.
Background, Aim and Scope Sustainability is a well recognised goal which is difficult to manage due to its complexity. As part of a series of sustainability management tools, a Product Sustainability Index (PSI) is translating the sustainability aspects to the organization of vehicle product development of Ford of Europe, thus allocating ownership and responsibility to that function. PSI is limiting the scope to those key environmental, social and economic characteristics of passenger vehicles that are controllable by the product development organisation. Materials and Methods: The PSI considers environmental, economic and social aspects based on externally reviewed life cycle environmental and cost aspects (Life Cycle Assessment, Cost of ownership / Life Cycle Costing), externally certified aspects (allergy-tested interior) and related aspects as sustainable materials, safety, mobility capability and noise. After the kick-off of their product development in 2002, the new Ford S-MAX and Ford Galaxy are serving as a pilot for this tool. These products are launched in Europe in 2006. The tracking of PSI performance has been done by engineers of the Vehicle Integration department within the product development organization. The method has been translated in an easy spreadsheet tool. Engineers have been trained within one hour trainings. The application of PSI by vehicle integration followed the principle to reduce the need for any incremental time or additional data to a minimum. PSI is adopted to the existing decision-making process. End of 2005, an internal expert conducted a Life Cycle Assessment and Life Cycle Costing (LCC) study for verification purposes using commercial software. This study and the PSI have been scrutinized by an external review panel according to ISO14040 and, by taking into consideration the on-going SETAC, work in the field of LCC. Results: The results of the Life Cycle based indicators of PSI as calculated by non-experts are fully in line with those of the more detailed expert study. The difference is below 2%. The new Ford Galaxy and Ford S-MAX shows significantly improved performance regarding the life cycle air quality, use of sustainable materials, restricted substances and safety compared to the previous model Galaxy. The affordability (Life Cycle Cost of Ownership) has also been improved when looking at the same engine types. Looking at gasoline versus diesel options, the detailed study shows under what conditions the diesel options are environmentally preferable and less costly (mileage, fuel prices, etc.). Discussion: The robustness of results has been verified in various ways. Based also on Sensitivity and Monte-Carlo Analysis, case study-specific requirements have been deduced defining criteria for a significant environmental improvement between the various vehicles. Only if the differences of LCIA results between two vehicles are larger than a certain threshold are the above-mentioned results robust. Conclusions: In general terms, an approach has been implemented and externally reviewed that allows non-experts to manage key environmental, social and economic aspects in the product development, also on a vehicle level. This allows mainstream functions to take ownership of sustainability and assigns accountability to those who can really decide on changes affecting the sustainability performance. In the case of Ford S-MAX and Galaxy, indicators from all three dimensions of sustainability (environment, social and economic) have been improved compared to the old Ford Galaxy. Recommendations and Perspectives: Based on this positive experience, it is recommended to make, in large or multinational organizations, the core business functions directly responsible and accountable for managing their own part of environmental, social and economic aspects of sustainability. Staff functions should be limited to starting the process with methodological and training support and making sure that the contributions of the different main functions fit together.  相似文献   
59.
In this study the environmental profile of Iranian rapeseed cultivation was analysed with a Life Cycle Assessment (LCA) approach, in order to identify the hot spots of the system. Also, in order to apply environmental indicators for agricultural decision making purposes, the environmental burden of different residue management practices were compared. Primary data were collected from 150 rapeseed farms from the Iranian Mazandaran province. The system considers a cradle-to-farm gate boundary, and the functional unit was regarded as being one Mg of rapeseed production. The LCA results indicate that the global warming potential amounts to 1181.6 kg CO2eq Mg−1. Also, the acidification and eutrophication potentials were found to be 23.3 kg SO2eq Mg−1 and 18 kg PO43eq Mg−1, respectively. The results also reveal that environmental emissions of crop production were significantly affected by residue management practices. Specifically, rapeseed residue removal from the field is the most environmentally-friendly practice. This is followed by a scenario involving residue incorporation in the soil. The practice of burning such residue entails the highest environmental emissions. In conclusion, reducing the consumption of chemical fertilisers, especially nitrogen based ones, is important for decreasing the environmental footprints in the area. Furthermore, avoiding crop residue burning and developing rapeseed-bean rotation are favourable management strategies for establishing more environmentally-friendly rapeseed production systems in the region.  相似文献   
60.
泛函连接网络计算软件及其在生物多样性研究中的应用   总被引:14,自引:0,他引:14  
针对农田生物多样性分析的需要,研制出泛函连接网络(FLANN)计算软件。该软件由7个Java类和1个HTML文件组成,是一种Internet在线计算工具,可运行于多种操作系统和Web浏览器上,并在各种类型的PC及工作站上使用,可读取多种类型的数据库文件。对水稻田昆虫生物多样性的两组取样调查数据Zmar18和Zapr15,用生物多样性工具软件LUMP和非监督分类-离差平方和聚类法进行统计归纳及分类,分别划分为21个和20个功能群,各包含60个样本。以FLANN计算软件对昆虫生物多样性进行了模式分类分析。结果表明,泛函连接网络的模式分类及预测与实际测查结果吻合良好。泛函连接网络Internet在线计算软件的应用可促进生物多样性数据采集和分析的规范化,有利于数据和信息共享,也为形成高度的生物多样性智能分析系统提供了一种工具。  相似文献   
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