基于生命周期评价的上海市水稻生产的碳足迹

碳足迹是指由企业、组织或个人引起的碳排放的集合。参照PAS2050规范并结合生命周期评价方法对上海市水稻生产进行了碳足迹评估。结果表明:(1)目前上海市水稻生产的碳排放为11.8114 t CO2e/hm2,折合每吨水稻生产周期的碳足迹为1.2321 t CO2e;(2)稻田温室气体排放是水稻生产最主要的碳排放源,每吨水稻生产的总排放量为0.9507 t CO2e,占水稻生产全部碳排放的77.1%,其中甲烷(CH4)又是最主要的温室气体,对稻田温室气体碳排放的贡献率高达96.6%;(3)化学肥料的施用是第二大碳排放源,每吨水稻生产的总排放量为0.2044 t CO2e,占水稻生产总碳排放的16.5%,其中N最高,排放量为0.1159 t CO2e。因此,上海低碳水稻生产的关键在降低稻田甲烷的排放,另外可通过提高氮肥利用效率,减少氮肥施用等方法减少种植过程中碳排放。     

Biodiesel production from Jatropha curcas: a critical review

The fuel crisis and environmental concerns, mainly due to global warming, have led researchers to consider the importance of biofuels such as biodiesel. Vegetable oils, which are too viscous to be used directly in engines, are converted into their corresponding methyl or ethyl esters by a process called transesterification. With the recent debates on “food versus fuel,” non-edible oils, such as Jatropha curcas, are emerging as one of the main contenders for biodiesel production. Much research is still needed to explore and realize the full potential of a green fuel from J. curcas. Upcoming projects and plantations of Jatropha in countries such as India, Malaysia, and Indonesia suggest a promising future for this plant as a potential biodiesel feedstock. Many of the drawbacks associated with chemical catalysts can be overcome by using lipases for enzymatic transesterification. The high cost of lipases can be overcome, to a certain extent, by immobilization techniques. This article reviews the importance of the J. curcas plant and describes existing research conducted on Jatropha biodiesel production. The article highlights areas where further research is required and relevance of designing an immobilized lipase for biodiesel production is discussed.     

玉米秸秆基纤维素乙醇生命周期能耗与温室气体排放分析

生命周期评价是目前分析产品或工艺的环境负荷唯一标准化工具,利用其生命周期分析方法可以有效地研究纤维素乙醇生命周期能耗与温室气体排放问题。为了定量解释以玉米秸秆为原料的纤维素乙醇的节能和温室气体减排潜力,利用生命周期分析方法对以稀酸预处理、酶水解法生产的玉米秸秆基乙醇进行了生命周期能耗与温室气体排放分析,以汽车行驶1 km为功能单位。结果表明：与汽油相比,纤维素乙醇E100 (100％乙醇) 和E10 (乙醇和汽油体积比=1∶9) 生命周期化石能耗分别减少79.63％和6.25％,温室气体排放分别减少53.98％和6.69％;生物质阶段化石能耗占到总化石能耗68.3％,其中氮肥和柴油的生命周期能耗贡献最大,分别占到生物质阶段的45.78％和33.26％;工厂电力生产过程的生命周期温室气体排放最多,占净温室气体排放量的42.06％,提升技术减少排放是降低净排放的有效措施。     

Life cycle assessment of forest biomass energy feedstock in the Northeast United States

Life cycle assessment (LCA) was combined with primary data from nine forest harvesting operations in New York, Maine, Massachusetts, and Vermont, from 2013 to 2019 where forest biomass (FB) for bioenergy was one of several products. The objective was to conduct a data‐driven study of greenhouse gas emissions associated with FB feedstock harvesting operations in the Northeast United States. Deterministic and stochastic LCA models were built to simulate the current FB bioenergy feedstock supply chain in the Northeast US with a cradle‐to‐gate scope (forest harvest through roadside loading) and a functional unit of 1.0 Mg of green FB feedstock at a 50% moisture content. Baseline LCA, sensitivity analysis, and uncertainty analyses were conducted for three different FB feedstock types—dirty chips, clean chips, and grindings—enabling an empirically driven investigation of differences between feedstock types, individual harvesting process contributions, and literature comparisons. The baseline LCA average impacts were lower for grindings (4.57 kg CO_2eq/Mg) and dirty chips (7.16 kg CO_2eq/Mg) than for clean chips (23.99 kg CO_2eq/Mg) under economic allocation, but impacts were of similar magnitude under mass allocation, ranging from 24.42 to 27.89 kg CO_2eq/Mg. Uncertainty analysis showed a wider range of probable results under mass allocation compared to economic allocation. Sensitivity analysis revealed the impact of variations in the production masses and total economic values of primary products of forest harvests on the LCA results due to allocation of supply chain emissions. The high variability in fuel use between logging contractors also had a distinct influence on LCA results. The results of this study can aid decision‐makers in energy policy and guide emissions reductions efforts while informing future LCAs that expand the system boundary to regional FB energy pathways, including electricity generation, transportation fuels, pellets for heat, and combined heat and power.     

Life cycle assessment of fuel ethanol from cassava in Thailand

Goal and Scope  A well-to-wheel analysis has been conducted for cassava-based ethanol (CE) in Thailand. The aim of the analysis is to assess the potentials of CE in the form of gasohol E10 for promoting energy security and reducing environmental impacts in comparison with conventional gasoline (CG). Method  In the LCA procedure, three separate but interrelated components: inventory analysis, characterization and interpretation were performed for the complete chain of the fuel life cycle. To compare gasohol E10 and CG, this study addressed their impact potentials per gasoline-equivalent litre, taking into account the performance difference between gasohol and gasoline in an explosion motor. Results and Discussions  The results obtained show that CE in the form of E10, along its whole life cycle, reduces certain environmental loads compared to CG. The percentage reductions relative to CG are 6.1% for fossil energy use, 6.0% for global warming potential, 6.8% for acidification, and 12.2% for nutrient enrichment. Using biomass in place of fossil fuels for process energy in the manufacture of ethanol leads to improved overall life cycle energy and environmental performance of ethanol blends relative to CG. Conclusions and Outlook  The LCA brings to light the key areas in the ethanol production cycle that researchers and technicians need to work on to maximize ethanol’s contribution to energy security and environmental sustainability ESS-Submission Editor: Mark Goedkoop (goedkoop@pre.nl)     

Life cycle assessment of biofuels: Energy and greenhouse gas balances

The promotion of biofuels as energy for transportation in the industrialized countries is mainly driven by the perspective of oil depletion, the concerns about energy security and global warming. However due to sustainability constraints, biofuels will replace only 10 to 15% of fossil liquid fuels in the transport sector. Several governments have defined a minimum target of GHG emissions reduction for those biofuels that will be eligible to public incentives, for example a 35% emissions reduction in case of biofuels in Members States of the European Union. This article points out the significant biases in estimating GHG balances of biofuels stemming from modelling choices about system definition and boundaries, functional unit, reference systems and allocation methods. The extent to which these choices influence the results is investigated. After performing a comparison and constructive criticism of various modelling choices, the LCA of wheat-to-bioethanol is used as an illustrative case where bioethanol is blended with gasoline at various percentages (E5, E10 and E85). The performance of these substitution options is evaluated as well. The results show a large difference in the reduction of the GHG emissions with a high sensitivity to the following factors: the method used to allocate the impacts between the co-products, the type of reference systems, the choice of the functional unit and the type of blend. The authors come out with some recommendations for basing the estimation of energy and GHG balances of biofuels on principles such as transparency, consistency and accuracy.     

Life cycle greenhouse gas emissions of residential battery storage systems: A German case study

Battery storage systems (BSSs) are popular as a means to increase the self-consumption rates of residential photovoltaics. However, their environmental impact is under discussion, given the greenhouse gas emissions caused by the production and the efficiency losses during operation. Against this background, we carry out a holistic environmental assessment of residential BSSs by combining a partial life cycle assessment for the production phase with a detailed simulation of 162 individual German households for the operational phase. As regards the production phase, we only find small differences between the carbon footprints of different cell chemistries. Moreover, we can show that the balance of plant components have a comparable impact on the global warming potential as the cell modules. In terms of the operational phase, our simulations show that BSSs can compensate at least parts of their efficiency losses by shifting electricity demand from high-emission to low-emission periods. Under certain conditions, the operational phase of the BSSs can even overcompensate the emissions from the production phase and lead to a positive environmental impact over the lifetime of the systems. As the most relevant drivers, we find the exact emissions at the production stage, the individual household load patterns, the system efficiency, and the applied operational strategy.     

Life cycle assessment of contaminated sites remediation

For the federal state of Baden-Wiirttemberg, Germany, the decision tool “Umweltbilanz von Altlastensanierungsverfahren” has been developed and found suitable for the quantification and evaluation of environmental impacts caused by remediation of contaminated sites. The developed tool complements the remediation toolbox of Baden-Wiirttemberg. The tool includes a streamlined life cycle assessment (LCA) and a synopsis of the LCA results with the results of a risk assessment of the contaminated site. The risk assessment tool is not explained here. The data base for the life cycle inventory includes several techniques used in remedial actions. The life cycle impact assessment utilises 14 impact categories. The method allows comparisons between remedial options for specific contaminated sites. A software tool has been developed to be available in 1999.     

Life cycle assessment of biodiesel production from microalgae in ponds

This paper analyses the potential environmental impacts and economic viability of producing biodiesel from microalgae grown in ponds. A comparative Life Cycle Assessment (LCA) study of a notional production system designed for Australian conditions was conducted to compare biodiesel production from algae (with three different scenarios for carbon dioxide supplementation and two different production rates) with canola and ULS (ultra-low sulfur) diesel. Comparisons of GHG (greenhouse gas) emissions (g CO₂-e/t km) and costs (¢/t km) are given. Algae GHG emissions (−27.6 to 18.2) compare very favourably with canola (35.9) and ULS diesel (81.2). Costs are not so favourable, with algae ranging from 2.2 to 4.8, compared with canola (4.2) and ULS diesel (3.8). This highlights the need for a high production rate to make algal biodiesel economically attractive.     

Environmental footprinting of hospitals: Organizational life cycle assessment of a Canadian hospital

Healthcare is a critical and complex service sector with direct and indirect greenhouse gas (GHG) emissions amounting to 5%–10% of the national total in developed economies like Canada and the United States. Along with a growing, albeit sporadic, set of life cycle assessment (LCA) (and “carbon footprinting”) studies of specific medical products and procedures, there is growing interest in “environmental footprinting” of hospitals. In this article, we advance this rapidly evolving area through a comprehensive organizational LCA of a 40-bed hospital in British Columbia, Canada, in its 2019 fiscal year. Our results indicate that the total environmental footprint of the hospital includes, among other things, global warming potential of 3500–5000 t CO₂ eq. (with 95% confidence). “Hotspots” in this footprint are attributable to energy and water use (and wastewater released), releases of anesthetic gases (which are potent GHGs), and the upstream production of the thousands of materials, chemicals, pharmaceuticals, and other products used in the hospital. The generalizability and comparability of these results are limited by inconsistencies across the few environmental footprinting studies of hospitals conducted to date. Nonetheless, our novel methodological approach, in which we compiled new LCA data for 200 goods and services used in healthcare—strategically selected to statistically represent the 2927 unique products in the hospital's “supply-chains”—has broad applicability in healthcare and beyond.     

Integrating cost-benefits analysis and life cycle assessment of green roofs: a case study in Florida

Abstract

Multiple environmental benefits can be achieved by using a green roof instead of conventional roofs. To better understand the LCA and cost-effectiveness of a green roof, a case study was performed. Two energy models, one with conventional white roof and the other with green roof, were created using eQUEST software to compare the influence of green roof on building energy consumption. The results indicated that the application of a green roof reduced annual space heating and cooling electricity consumption by 9500 kWh (2.2 kWh per square meter). The LCA shows that by using an extensive green roof in lieu of a conventional white roof the LCA measures at the product, construction, and end-of-life stages increased due to the use of additional layers. However, these increases are offset by the reduction of LCA measures at the use stage such that the overall environmental impacts of green roof is less than that of conventional roof. To find out the cost-effectiveness of green roof, a 50-year cost-benefits analysis was conducted. The analysis showed that the net savings of the green roof is negative compared to the white roof it replaced due to its higher initial cost and follow on maintenance cost.     

Life cycle assessment in the telecommunication industry: A review

Background, Goal and Scope Today, after the technologically and commercially successful breakthrough of electronic telecommunication facilities, rapid and globally untrammelled information exchange has become an indispensable service in daily life. Associated with the tremendous growth in electronic telecommunication hardware (GSMAssociation 2005), however, was and continues to be an increasing awareness of the environmental effects related to both the operation and the production, as well as the End-of-Life (EoL) treatment of such communication equipment. Environmental concerns, for example, have resulted in various governmental regulations such as the WEEE-(CEC 2003b) and the RoHS-directives (CEC 2003a). To analyse, interpret and improve the environmental performance of electronic telecommunication equipment, life cycle assessment (LCA) is increasingly recognised as one promising analytical tool. Based on a thorough review of the scientific work and by discussing industrial views, this paper is intended to determine the key milestones achieved, to analyse the current research situation and to outline the key challenges concerning LCA and electronic telecommunication industries. Method Starting with a brief reflection of the LCA approach, the particularities in context with telecommunication products1 are discussed. Exemplary for various stakeholders participating in the supply chain of telecommunication means recent industry perspectives are also presented. Results In the core section of the proposed paper, the pertinent scientific literature on LCA and electronic telecommunication means is reviewed and the most impressive achievements are documented. Particular attention is dedicated to subcomponents of individual electronic telecommunication devices (e.g. Printed Wiring Board Assemblies (PWBA) of mobile phones), components of mobile communication networks (e.g. Base Transceiver Stations (BTS)) and entire networks concentrating on product comparisons, inventory approaches, impact assessment method development, result interpretations and presentation, and usability of LCA in decision-making. Discussion From the reviewed scientific literature and industry views, it was found that telecommunication products, in general, represent complex objects requiring a well thought-out performance of the LCA tool. It has been shown that today there is a lack of stakeholder involvement resulting in LCA studies which only partly fulfil the expectations of the contractors. In this spirit it was recognised, at present, that most of the LCA studies on telecommunication equipment result in bulky and stakeholder unspecific compilations of findings impossible to be used in rapid decision-making. This aspect may explain why LCA so far is not or only partly integrated into decision-making of globally integrated industries, such as in telecommunication industries. Conclusions In summary, it can be stated that LCA represents a promising alternative to analyse, to interpret and essentially to adjust the environmental performance of electronic telecommunication products. The review showed that there is a need to focus research efforts in order to arrive at sound improvements of the LCA methodology. Perspectives The conclusions from the presented review suggest concentrating in particular on further development of the LCA methodology with respect to efficiency, effectivity and flexibility. This challenge is associated with the need for LCA to be understood as a process rather than a discontinuously applicable tool, attending industrial processes, in essence to contribute to improved environmental performances of products. In this context, particular attention should be paid to proper stakeholder involvement and continuous exchange of concentrated information relevant for the respective stakeholder.     

Renewable Energy from Willow Biomass Crops: Life Cycle Energy,Environmental and Economic Performance

Short-rotation woody crops (SRWC) along with other woody biomass feedstocks will play a significant role in a more secure and sustainable energy future for the United States and around the world. In temperate regions, shrub willows are being developed as a SRWC because of their potential for high biomass production in short time periods, ease of vegetative propagation, broad genetic base, and ability to resprout after multiple harvests. Understanding and working with willow's biology is important for the agricultural and economic success of the system.

The energy, environmental, and economic performance of willow biomass production and conversion to electricity is evaluated using life cycle modeling methods. The net energy ratio (electricity generated/life cycle fossil fuel consumed) for willow ranges from 10 to 13 for direct firing and gasification processes. Reductions of 70 to 98 percent (compared to U.S. grid generated electricity) in greenhouse gas emissions as well as NO_x, SO₂, and particulate emissions are achieved.

Despite willow's multiple environmental and rural development benefits, its high cost of production has limited deployment. Costs will be lowered by significant improvements in yields and production efficiency and by valuing the system's environmental and rural development benefits. Policies like the Conservation Reserve Program (CRP), federal biomass tax credits and renewable portfolio standards will make willow cost competitive in the near term.

The avoided air pollution from the substitution of willow for conventional fossil fuel generated electricity has an estimated damage cost of $0.02 to $0.06 kWh^?1. The land intensity of about 4.9 × 10^?5 ha-yr/kWh is greater than other renewable energy sources. This may be considered the most significant limitation of willow, but unlike other biomass crops such as corn it can be cultivated on the millions of hectares of marginal agricultural lands, improving site conditions, soil quality and landscape diversity. A clear advantage of willow biomass compared to other renewables is that it is a stock resource whereas wind and PV are intermittent. With only 6 percent of the current U.S. energy consumption met by renewable sources the accelerated development of willow biomass and other renewable energy sources is critical to address concerns of energy security and environmental impacts associated with fossil fuels.     

Sources of variability in greenhouse gas and energy balances for biofuel production: a systematic review

Across the energy sector, alternatives to fossil fuels are being developed, in response to the dual drivers of climate change and energy security. For transport, biofuels have the greatest potential to replace fossil fuels in the short‐to medium term. However, the ecological benefits of biofuels and the role that their deployment can play in mitigating climate change are being called into question. Life Cycle Assessment (LCA) is a widely used approach that enables the energy and greenhouse gas (GHG) balance of biofuel production to be calculated. Concerns have nevertheless been raised that published data show widely varying and sometimes contradictory results. This review describes a systematic review of GHG emissions and energy balance data from 44 LCA studies of first‐ and second‐generation biofuels. The information collated was used to identify the dominant sources of GHG emissions and energy requirements in biofuel production and the key sources of variability in published LCA data. Our analysis revealed three distinct sources of variation: (1) ‘real’ variability in parameters e.g. cultivation; (2) ‘methodological’ variability due to the implementation of the LCA method; and (3) ‘uncertainty’ due to parameters rarely included and poorly quantified. There is global interest in developing a sustainability assessment protocol for biofuels. Confidence in the results of such an assessment can only be assured if these areas of uncertainty and variability are addressed. A more defined methodology is necessary in order to allow effective and accurate comparison of results. It is also essential that areas of uncertainty such as impacts on soil carbon stocks and fluxes are included in LCA assessments, and that further research is conducted to enable a robust calculation of impacts under different land‐use change scenarios. Without the inclusion of these parameters, we cannot be certain that biofuels are really delivering GHG savings compared with fossil fuels.     

Isolation of novel microsatellites from Jatropha curcas L. and their cross-species amplification

Jatropha curcas L., a member of the Euphorbiaceae, is widely distributed in different parts of the globe. In the present study, 12 microsatellites were isolated from J. curcas and their cross-species amplification was checked in six species of genus Jatropha. Within J. curcas, observed and expected heterozygosities ranged from 0.94 to 0.54 and from 0.95 to 0.56, respectively. Of the 12 loci, five showed significant deviation from Hardy-Weinberg equilibrium. There was no significant linkage disequilibrium detected between any of the loci. The markers isolated in the present investigation will be useful for assessing the population diversity and genetic structure of J. curcas and also in other species of Jatropha.     

Life cycle assessment of natural gas power plants in Thailand

Background, aim, and scope  The main primary energy for electricity in Thailand is natural gas, accounting for 73% of the grid mix. Electricity generation from natural gas combustion is associated with substantial air emissions. The two technologies currently used in Thailand, thermal and combined cycle power plant, have been evaluated for the potential environmental impacts in a “cradle-to-grid” study according to the life cycle assessment (LCA) method. This study evaluates the environmental impacts of each process of the natural gas power production over the entire life cycle and compares two different power plant technologies currently used in Thailand, namely, combined cycle and thermal. Materials and methods  LCA is used as a tool for the assessment of resource consumption and associated impacts generated from utilization of natural gas in power production. The details follow the methodology outlined in ISO 14040. The scope of this research includes natural gas extraction, natural gas separation, natural gas transmission, and natural gas power production. Most of the inventory data have been collected from Thailand, except for the upstream of fuel oil and fuel transmission, which have been computed from Greenhouse gases, Regulated Emissions, and Energy use in Transportation version 1.7 and Global Emission Model for Integrated Systems version 4.3. The impact categories considered are global warming, acidification, photochemical ozone formation, and nutrient enrichment potential (NEP). Results  The comparison reveals that the combined cycle power plant, which has a higher efficiency, performs better than the thermal power plant for global warming potential (GWP), acidification potential (ACP), and photochemical ozone formation potential (POCP), but not for NEP where the thermal power plant is preferable. Discussion  For the thermal power plant, the most significant environmental impacts are from power production followed by upstream of fuel oil, natural gas extraction, separation, and transportation. For the combined cycle power plant, the most significant environmental impacts are from power production followed by natural gas extraction, separation, and transportation. The significant difference between the two types of power production is mainly from the combustion process and feedstock in power plant. Conclusions  The thermal power plant uses a mix of natural gas (56% by energy content) and fuel oil (44% by energy content); whereas, the combined cycle power plant operates primarily on natural gas. The largest contribution to GWP, ACP, and NEP is from power production for both thermal as well as combined cycle power plants. The POCP for the thermal power plant is also from power production; whereas, for combined cycle power plant, it is mainly from transmission of natural gas. Recommendations and perspectives  In this research, we have examined the environmental impact of electricity generation technology between thermal and combined cycle natural gas power plants. This is the overview of the whole life cycle of natural gas power plant, which will help in decision making. The results of this study will be useful for future power plants as natural gas is the major feedstock being promoted in Thailand for power production. Also, these results will be used in further research for comparison with other feedstocks and power production technologies.     

Life cycle assessment in green chemistry

Background, Aims and Scope Using renewable feedstock and introducing biocatalysts in the chemical industry have been suggested as the key strategies to reduce the environmental impact of chemicals. The Swedish interdisciplinary programme ‘Greenchem’, is aiming to develop these strategies. One target group of chemicals for Greenchem are wax esters which can be used in wood surface coatings for wood furniture, etc. The aim of this study was to conduct a life cycle assessment of four different wood surface coatings, two wax-based coatings and two lacquers using ultra violet light for hardening (UV lacquers). One of the two wax-based coatings is based on a renewable wax ester produced with biocatalysts from rapeseed oil, denoted ‘green wax’, while the other is based on fossil feedstock and is denoted ‘fossil wax’. The two UV lacquers consist of one ‘100% UV’ coating and one ‘water-based UV’ coating. The scope was to compare the environmental performance of the new ‘green’ coating with the three coatings which are on the market today. Methods The study has a cradle-to-grave perspective and the functional unit is ‘decoration and protection of 1 m² wood table surface for 20 years’. Extensive data collection and calculations have been performed for the two wax-based coatings, whereas mainly existing LCI data have been used to characterise the production of the two UV lacquers. Results For all impact categories studied, the ‘100% UV’ lacquer is the most environmentally benign alternative. The ‘water-based UV’ is the second best alternative for all impact categories except EP, where the ‘fossil wax’ is slightly better. For GWP the ‘fossil wax’ has the highest contribution followed by the ‘green wax’. For AP and EP it is the ‘green wax’ that makes the highest environmental impact due to the contribution from the cultivation of the rapeseed and the production of the rapeseed oil. For POCP the ‘fossil wax’ makes the highest contribution, slightly higher than the contribution from the ‘green wax’. Also the energy requirements for the ‘100% UV’ lacquer is much lower than for the other coatings. The results from the toxicological evaluation conducted in this study, which was restricted to include only the UV lacquers, are inconclusive, giving different results depending on the model chosen, EDIP97 or USES. Discussion The result in this study shows that the environmental benefits of using revewable feedstock and processes based on biocatalysis in the production of wax esters used in wood surface coatings are rather limited. This is due to the high environmental impact from other steps in the life cycle of the coating. Conclusions Overall the ‘100% UV’ lacquer seems to be the best alternative from an environmental point of view. This study shows that the hot spots of the life cycle of the coatings are the production of the ingredients, but also the application and drying of the coatings. The toxicity assessment shows the need for the development of a new model, a model which finds common ground in order to overcome the current situation of diverging results of toxicity assessments. The results in this study also point to the importance of investigating the environmental performance of a product based on fossil or renewable feedstock from a life cycle perspective. Recommendations and Perspectives The results in this study show that an efficient way to improve the wood coating industry environmentally is to increase the utilization of UV lacquers that are 100% UV-based. These coatings can also be even further improved by introducing biocatalytic processes and producing epoxides and diacrylates from renewable raw material instead of the fossil-based ones produced with conventional chemical methods in use today. In doing this, however, choosing a vegetable oil with good environmental performance is important. An alternative application of the ‘green wax’ analysed in this study may be as an ingredient in health care products, for example, which may result in greater environmental benefits than when the wax is used inwood coating products. The results in this study illustrate the importance of investigating the environmental performance of a product from cradle-to-grave perspective and not consider it ‘green’ because it is based on renewable resources.     

麻疯树逆境蛋白(curcin 2)基因在烟草中的表达

麻疯树（Jatropha curcas）幼苗在干旱、高低温胁迫和真菌浸染下,其叶片中诱导产生了一种新的毒蛋白curcin 2。这意味着curcin 2在其它植物中的异源表达可能会增强植物对外界胁迫的抵抗。curcin 2 cDNA的两个片断：cur2p片断（编码前成熟蛋白）和cur2m片断（编码成熟蛋白）,通过农杆菌的介导分别转化烟草并获得转基因植株。但是,只有在插入了cur2p片断的烟草中检测到了curcin 2蛋白的表达。同时,curcin 2在烟草中的表达增强了植株对烟草花叶病毒（TMV）的抗性。     

麻疯树柄细蛾形态和生物学特性观察

麻疯树柄细蛾Stomphastis thraustica Meyrick是在我国新发现的麻疯树Jatropha curcas L.潜叶蛾类重要害虫。通过室内饲养与野外调查相结合对该虫形态、发育习性及生活史进行了研究。本文对麻疯树柄细蛾成虫、卵、各龄幼虫和蛹的形态及大小进行了详细描述。95.54%(n=426)的老熟幼虫在10点至18点结茧。89.19%（n=111）在夜间20点至次日凌晨6点羽化。交配在清晨进行, 持续30~210 min不等。87.53%（n=441）的卵在夜间20点以后至次日6点以前产出。卵多产于叶脉边缘与叶片形成的凹陷处。66.77%（n=8 266）的卵产于叶片背面, 其余产于叶片正面。每雌产卵平均60.03粒(n=32)。麻疯树柄细蛾在攀枝花全年均可发育。以成虫在每年2月至5月越冬。一年发生10代以上, 世代重叠明显。以6月室外平均气温25.15℃条件下, 全世代发育需18~20 d。卵期3~4 d, 1龄幼虫期1 d, 2龄幼虫期1~2 d, 3龄幼虫期1~2 d, 4龄幼虫期1~2 d, 5龄幼虫期2~3 d, 预蛹期1 d, 蛹期4~6 d, 成虫产卵前期1 d。     

Life Cycle assessment of bio-ethanol derived from cellulose

Objective, Scope, Background  A comprehensive Life Cycle Assessment was conducted on bio-ethanol produced using a new process that converts cellulosic biomass by enzymatic hydrolysis. Options for sourcing the feedstock either from agricultural and wood waste, or, if the demand for bio-ethanol is sufficient, from cultivation are examined. The main focus of the analysis was to determine its potential for reducing greenhouse gas emissions in a 10% blend of this bio-ethanol with gasoline (E10) as a transportation fuel. Methods  SimaPro 4.0 was used as the analysis tool, which allowed a range of other environmental impacts also to be examined to assess the overall relative performance to gasoline alone. All impacts were assigned to the fuel because of uncertainties in markets for the by-products. This LCA therefore represents a worst case scenario. Results, Conclusion  It is shown that E10 gives an improved environmental performance in some impact categories, including greenhouse gas emissions, but has inferior performances in others. Whether the potential benefits of the bio-ethanol blend to reduce greenhouse gas emissions will be realized is shown to be particularly sensitive to the source of energy used to produce the process steam required to break down the cellulose to produce sugars and to distil the final product. One key area where improvements in environmental performance might be derived is in enzyme production. Recommendations and Outlook  The LCA profile helps to highlight those areas where positive and negative environmental impacts can be expected. Technological innovation can be directed accordingly to preserve the benefits while minimizing the negative impacts as development progresses to commercial scales.