装置施工和检修中法兰、垫片的更换和选择

文章对法兰、垫片泄漏对石油化工企业的安全、环保造成的威胁进行了分析，提出在设计中合理选用管道器材是保证管道和设备正常运行的关键。     

Designs with a priori information for nonmarket valuation with choice experiments: A Monte Carlo study

Good practice in experimental design is essential for choice experiments used in nonmarket valuation. We review the practice of experimental design for choice experiments in environmental economics and we compare it with advances in experimental design. We then evaluate the statistical efficiency of four different designs by means of Monte Carlo experiments. Correct and incorrect specifications are investigated with gradually more precise information on the true parameter values. The data generating process (DGP) is based on estimates from data of a real study. Results indicate that D-efficient designs are promising, especially when based on Bayesian algorithms with informative prior. However, if good quality a priori information is lacking, and if there is strong uncertainty about the real DGP—conditions which are quite common in environmental valuation—then practitioners might be better off with shifted designs built from conventional fractional factorial designs for linear models.     

Some specialized risk assessment methodologies for vertebrate populations

We present three empirical methods for risk assessment in field studies of free-ranging vertebrates. First, we advocate statistical inference concerning population recruitment or mortality in response to ecological hazards. Second, if inferences about both recruitment and mortality are available, one can use a Leslie- Lefkovitch matrix to estimate the finite rate of population change () as a function of ecological hazards. Third, designed experiments can be conducted on samples of marked animals in natural environments to assess impacts and risks. These methods rely on either sophisticated capture-recapture or radio-tracking models, and on well-developed analysis theory. The use of uniquely marked animals is somewhat analogous to the use of tracers in other areas of risk assessment. We present examples of each approach and discuss some limitations.     

Retention of trace elements in coal-fired flue gas by a novel heterogeneous agglomeration technology

Heterogeneous agglomeration (HA) is a very potential technology for coal-fired flue gas treatment.In this paper,the distribution and migration mechanisms of trace elements (TEs such as Se,As and Pb in CFPPs were studied on a 30,000 m³/hr pilot-scale experimental plat form.The influences of HA on the removal efficiency of gaseous and particulate TEs were well analyzed.The results showed that Se,As and Pb were enriched in fly ash,and their sen sitivity to particle size is quite differen...     

NaCl在Zn(Ⅱ)-NaOH-H_2O体系中溶解度的测定及去除

等温溶解平衡法测定了283.2～323.2 K温度范围内NaCl在Zn(Ⅱ)-NaOH-H2O体系(cZn(Ⅱ)=0.6 mol/L、cNaOH=5.00mol/L)及NaOH-H2O体系(cNaOH=5.00 mol/L)中的溶解度。与NaOH-H2O、纯水体系相比,相同温度下NaCl在Zn(Ⅱ)-NaOH-H2O体系中溶解度最小。运用正交实验法对Zn(Ⅱ)-NaOH-H2O体系中NaCl的溶解度进行因素分析。结果表明,较高的cNaOH和cZn(Ⅱ)是造成NaCl溶解度急剧降低的主要原因,提高温度虽然对NaCl的溶解有促进作用但影响较小。最后,通过加热浓缩方式提高溶液NaOH和Zn的浓度,促使NaCl因溶解度骤降而结晶析出,首次实现了碱锌溶液中高浓度Cl-的大量去除。实验结果具有重要的工程应用价值。     

Non-market values of forest biodiversity and the impact of informing the general public: Insights from generalized multinomial logit estimations

Apart from the ethical argument around trade-off that individuals have to make between monetary and non-monetary value, application of stated preference method was exposed to another criticism related to the complexity of biodiversity issue and the capacity of the general public to provide accurate responses to willingness to pay elicitation survey. This paper tests how providing information about the ecological processes underlying forest management scenarios affects public preferences and their valuation of biodiversity in publicly owned forest land in France. The generalized multinomial logit models applied to choice experiment data suggests that all respondents adopt the same heuristics based on easily visible aspects of forest landscape, to reveal their use and nonuse values of biodiversity. However, when they receive additional ecological information, only those who are familiar with the biodiversity concept, have awareness of issues at stake, and have a regular use of forest tend to attach higher values to less known biodiversity component (fallen deadwood in this case). The paper concludes that “mass media campaign” has to be completed by environmental literacy programs, to improve people’s awareness and understanding of what biodiversity means from ecological functioning, then making economic valuation a useful tool from a conservation perspective.     

The Influence of Anthropogenic Contamination On Metals Release From Coastal Sediment Suspensions with Aerated Sea Water

The zinc, cadmium, copper and lead release from the uncontaminated and contaminated coastal sediments with aerated sea water was studied. the metals transfer to the dissolved forms was monitored during one-two months by differential pulse anodic voltammetry (DPASV). the sediments with different initial degree of contamination were sampled in the Peter the Great Bay, Sea of Japan around Vladivostok-the biggest city in Russian Far East. Sediment contamination by metals led to increased release to solution of zinc due to sulphide oxidation and cadmium on account of organic matter decomposition. the copper behaviour was complicated by strong binding with organic matter and enhancements of copper release can only be seen in sediment with a low organic matter content. Significant lead transfer to dissolved forms was not observed regardless of sediment contamination. the temperature affected the release of cadmium and copper through enhanced organic matter destruction. the dissolved metal fluxes from the sediment transformation are compared with metal fluxes towards bottom. Such comparisons show that second contamination by dissolved metals of the studied coastal environment may be important for cadmium only.     

Organic Contaminants from Sewage Sludge Applied to Agricultural Soils. False Alarm Regarding Possible Problems for Food Safety? (8 pp)

Goal, Scope and Background Sewage sludge produced in wastewater treatment contains large amounts of organic matter and nutrients and could, therefore, be suitable as fertiliser. However, with the sludge, besides heavy metals and pathogenic bacteria, a variety of organic contaminants can be added to agricultural fields. Whether the organic contaminants from the sludge can have adverse effects on human health and wildlife if these compounds enter the food chain or groundwater still remains a point of controversial discussion. Main Features This paper presents an overview on the present situation in Europe and a summary of some recent results on the possible uptake of organic contaminants by crops after addition to agricultural fields by sewage sludge. Results Greenhouse experiments and field trials were performed to study the degradation and uptake of organic micro-contaminants in sludge-amended agricultural soil in crops, such as barley and carrots grown in agricultural soil amended with anaerobically-treated sewage sludge from a wastewater treatment plant, but studies hitherto have revealed no immediate risks. Common sludge contaminants such as linear alkylbenzene sulphonates (LAS), nonylphenol ethoxylates (NPE), polycyclic aromatic hydrocarbons (PAH), bis(diethylhexyl) phthalate (DEHP), showed neither accumulation in soil nor uptake in plants. Discussion It is assumed that the annual amount of sewage sludge produced in Europe will increase in the future, mainly due to larger amounts of high quality drinking water needed by an increasing population and due to increasing demands for cleaner sewage water. Application of sewage sludge to agricultural soils is sustainable and economical due to nutrient cycling and disposal of sewage sludge. However, this solution also involves risks with respect to the occurrence of organic contaminants and other potentially harmful contents such as pathogens and heavy metals present in the sludge. There have been concerns that organic contaminants may accumulate in the soil, be taken up by plants and thereby transferred to humans via the food chain. Results obtained so far revealed, however, no immediate risk of accumulation of common organic sludge contaminants in soil or uptake in plants when applying sewage sludge to agricultural soil. With very high dosages of sewage sludge, there may be a risk for accumulation of very apolar contaminants, such as DEHP, to the soil. Conclusions Any conclusions on the safe use of sewage sludge in agriculture have to be drawn carefully, as the studies performed until now have been limited. Further studies are required, and before final statements can be drawn, it is imminent to study a larger variety of common crops and the effect sewage sludge application may have on a possible accumulation of organic contaminants in the crops. Furthermore, a larger variety of organic contaminants need to be studied and special focus should be given to contaminants newly introduced into the environment. Besides investigating possible plant uptake of organic contaminants, the fate of these compounds in soil after sludge application need to be monitored too. Here, special attention has to begiven to studies on degradation and the formation of degradation products, to weathering and to leaching effects on groundwater, to the application of different crops on the same field (crop rotation), to the use of full-width tillage and strip tillage, and to long term application of sewage sludge on the soil. Recommendations and Perspectives There are environmental, political as well as economical incentives to increase the agricultural application of sludge. However, such usage should be performed with care as there are also ways in which sludge fertilisation could harm the environment and human health. Recently, a new European COST Action (859) has been established covering the field of food safety and improved food quality. Part of the Action is dealing with the application of sewage sludge in agriculture. Before any political and economical measures can be taken, the pros and cons have to be sufficiently investigated on a scientific level first. ESS-Submission Editor: Prof. Elena Maestri (elena.maestri@unipr.it)     

Estimating the non-market benefits of climate change adaptation of river ecosystem services: A choice experiment application in the Aoos basin,Greece

Mountains are important global reservoirs of water resources. However they are highly vulnerable to climate change as limited alterations in temperature and precipitation may cause harmful effects to water systems. Southern Europe and especially Greece are expected to undergo a drought trend over the next decades, resulting in less recharge for the aquifers and water services reduction. Thus, climate change may distort both natural and socioeconomic characteristics of freshwater ecosystem services deteriorating the general social welfare related to them. This paper examines the economic impacts of climate change on river uses of the Aoos basin in Greece. In this regard, a choice experiment is conducted to estimate the value changes in different ecological and economic services in a mountain community. The econometric simulations using conditional logit, random parameters logit and latent class models reveal that despite existing preference heterogeneity, respondents on average derive positive and significant welfare effects from climate change adaptation measures. The findings of the survey may assist in adaptation planning for the Aoos River basin, with possible extensions to other river systems enduring similar climate change indications.     

Adoption of irrigation water policies to guarantee water supply: A choice experiment

More efficient and sustainable use of water is increasingly becoming an urgency in drought prone parts of the world. In particular, in water scarce regions such as the Mediterranean, water supply is expected to become more uncertain because of climate change. Consequently, pro-active policy initiatives are proposed to increase supply reliability. Local context is important when the effectiveness of policies is assessed. The aim of this paper is to evaluate farmers’ acceptance of policy strategies to increase water supply reliability in the Segura, a water scarce river basin in the south-east of Spain. Results from a choice experiment suggest that farmers are willing to pay twice as much as their current irrigation water price to ensure water supply reliability through government supply guaranteed programs. However, they are averse to any institutional changes that might assist the government to achieve increased water supply.