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41.
The role of business in sustainable consumption   总被引:2,自引:0,他引:2  
This paper explores the role of the business community in promoting sustainable consumption. While businesses play an important role in shaping social trends, including the growth of material consumption, allegations that individual corporations wield excessive power may have been overstated. Most of the time corporations are simply playing by the rules and culture of the market.Businesses have mostly assumed that their contribution to sustainability lies in improving eco-efficiency—staying within the current business framework. But sustainable consumption will require wider change, including shifts in the incentives that shape the actions of businesses and others, and a change in the culture that underlies market expectations. Firms, governments, the media and civil society may need to enter a dialogue together to develop a new story about the nature of prosperity and the role of the business community in promoting it. The initiative is most likely to come from civil society.  相似文献   
42.
The BIODEP model in terms of atmosphere-lake interactions was developed. The model was applied to an oligotrophic, dimictic high altitude lake (Lake Redo, Pyrenees) for a range of polychlorinated biphenyl (PCB) congeners. High altitude lakes, which receive their contaminant inputs uniquely from the atmosphere through long-range atmospheric transport, provide ideal controlled environments for the study of the interactions between atmospheric depositional and water column biogeochemical processes. The BIODEP model was able to predict dissolved water concentrations and PCB accumulation in the lake sediment within a factor of 2. This shows that the BIODEP model captures the essential processes driving the sink of POPs in high altitude lakes and that POP occurrence in the lake is driven by direct atmospheric inputs with limited influence from the watershed. An important seasonal variability in water column concentrations is predicted which should have important implications in sampling strategies. Furthermore, it is shown that diffusive air-water exchange dominated the PCB dynamics in the lake, especially for the less chlorinated biphenyls.  相似文献   
43.
For reducing greenhouse gas emissions, intensity targets are attracting interest as a flexible mechanism that would better allow for economic growth than emissions caps. For the same expected emissions, however, the economic responses to unexpected productivity shocks differ. Using a real business cycle model, we find that a cap dampens the effects of productivity shocks in the economy on all variables except for the shadow value of the emissions constraint. An emissions tax leads to the same expected outcomes as a cap but with greater volatility. Certainty-equivalent intensity targets maintain higher levels of labor, capital, and output than other policies, with lower expected costs and no more volatility than with no policy.  相似文献   
44.
目的研究不同温度热–冷循环处理对炮钢摩擦磨损性能的影响及其磨损机理。方法将PCrNi3MoVA炮钢分别在400、800℃的加热温度下进行热–冷循环处理,采用立式万能摩擦磨损实验机在不同的滑动速度下测试炮钢销与H96黄铜盘配副时的摩擦磨损性能,记录摩擦系数,测量炮钢销和黄铜盘的磨损量。采用扫描电子显微镜和能谱仪测量磨损后的炮钢销表面形貌及化学成分,分析其磨损机理。结果热–冷循环处理对炮钢销在100 r/min滑动速度下的摩擦系数的影响较小。随着热–冷循环处理中加热温度的升高,炮钢销的磨损量增大,而黄铜盘的磨损量受炮钢销热–冷循环处理的影响较小。炮钢销的磨损表面可见明显的因材料塑性变形剥落造成的凹坑和沟槽。随着滑动速度的增大,800℃–室温循环处理后,炮钢销的摩擦系数降低,磨损量在400 r/min时最大,在800 r/min时反而下降到接近于0。分析磨损表面发现,800 r/min时,黄铜磨屑与炮钢磨屑发生掺杂混合,附着于炮钢销的磨损表面,从而影响了炮钢销的摩擦磨损性能。结论热–冷循环处理对炮钢销–黄铜盘摩擦副摩擦系数的影响较小,但随着热–冷循环中加热温度的升高,炮钢销的耐磨损性能下降。滑动速度对炮钢销摩擦系数和磨损量的影响都较大,高的滑动速度下,黄铜磨屑与炮钢磨屑混合,并附着于炮钢销磨损表面,改变炮钢销的磨损机理。  相似文献   
45.
冻融对长白山森林土壤碳氮矿化的影响   总被引:1,自引:0,他引:1  
长白山地区秋末春初常常存在冻融过程,冻融过程影响土壤水分分布而改变土壤理化性质。通过室内模拟实验,研究了冻融过程(-20~15℃)对长白山阔叶红松(Pinus koraiensis)林和白桦(Betula platyphylla)林土壤有机碳和氮矿化过程的影响。结果表明,经过3次冻融循环,冻融处理土壤矿化速率显著高于对照处理,但经过多次冻融循环过程,冻融处理抑制土壤有机碳矿化过程,对照处理土壤有机碳矿化速率高于冻融处理(P=0.019)。在培养结束后,冻融处理的阔叶红松林和白桦林土壤无机氮质量分数,分别是对照处理的1.88倍和1.96倍;冻融次数也是影响土壤有机氮矿化的一个重要因素,35次冻融循环后,阔叶红松林和白桦林土壤中无机氮分别提高了2.10倍和2.81倍。冻融循环促进了土壤有机氮的矿化,有利于土壤中有效氮的累积,为春季植物生长提供足够的氮素,但也潜在增加了土壤中无机氮流失的风险。  相似文献   
46.
商务英语教学法初探   总被引:6,自引:0,他引:6  
商务英语是在国际商务环境下使用的专业英语,是一种特殊用途英语.商务英语与普通英语相比更侧重于应用.因此,在教学中应突破传统语言教学法,减少基础语言知识传授的比例,以培养学生语言应用能力为目的,增加产出性的数量和权重.并将教师授课与学生自主学习结合起来,建立以学生自主学习为中心的立体化、多样化、个性化的教学模式.  相似文献   
47.
ABSTRACT: Nutrient fluxes in precipitation, throughfall, and stemflow were studied in an oak-hickory forest in southern Illinois for a three-year period beginning in 1973. Nutrient inputs in these water related pathways were approximately one-half those of litterfall; a major nutrient return mechanism. Considering these water carried nutrients (116 kg/ha/yr), 38% was contributed by precipitation, 35% by throughfall and approximately 27% by stemflow. Although the total nutrient input is only one-half that of litterfall, the net impact on short-term nutrient requirements is considerable because of their immediate availability. Nutrient inputs in litter represent a delayed return mechanism because of the relatively slow decomposition process.  相似文献   
48.
This paper reviews analytical procedures for deducing from annual streamflow data information required for water resources systems planning. The procedure relies on two techniques to determine the extent that cycles exist in annual time series data. The first is to observe how the time series behaves around the mean annual flow. If it tends not to move across the mean frequently, it is concluded that a cyclical nature exists. The second technique is to observe the time path of accumulated departures from the mean annual flow. The validity of both techniques is questioned. The first because it uses mean flow as “normal” or the flow that the time series should fluctuate around. The second because the accumulated departure from the mean time series will be autocor-related even when the individual annual or seasonal flow observations are uncorrected. Alternative analytical techniques, which find no cycles, are presented.  相似文献   
49.
Paying thorough attention to cynical action and integrity could result in a less naive approach to ethics and moral communication. This article discusses the issues of integrity and cynicism on a theoretical and on a more practical level. The first part confronts Habermas’s approach of communicative action with Sloterdijk’s concept of cynical reason. In the second part, the focus will be on the constraints and possibilities of moral communication within a business context. Discussing the corporate integrity approach of Kaptein and Wempe will provide this focus. Their approach can be considered as a valuable contribution to the question of how to deal with (dilemmas of) conflicting interests, open discussion, fairness, and strategic decision-making in the context of stakeholder dialog. However, it is concluded that Kaptein and Wempe seem to overstretch the concept of corporate integrity by their inclination to make it an all-purpose remedy for corporate dilemmas.  相似文献   
50.
What kinds of PV project configurations do lenders prefer to finance? Recent developments in the field of renewable energy project finance have reinforced the need for investigation, as fundraising has become more challenging and project evaluation by banks more demanding. To contribute to the limited research in this field, we focus on photovoltaic projects and report from an Adaptive Choice-Based Conjoint experiment with German experts in project finance. We find a bias which we call “debt for brands”. Simulations reveal that debt investors prefer projects with premium brand technology (modules, inverters) to low-cost technology. Although we assumed that lenders prefer projects with the highest Debt Service Cover Ratio (DSCR), they favor projects with lower DSCR, as long as those projects include premium brand technology. We find that, if premium brands were engaged, lenders would also choose projects with higher risk. Our findings have implications for renewable energy project finance in practice and research.  相似文献   
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