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151.
The kinetics of famotidine (FAM) transformation under the influence of various factors, important from the environmental point of view, was investigated in aqueous solutions. The degradation processes using UV, H2O2, UV/H2O2, H2O2/Fe2+, and UV/H2O2/Fe2+ were studied. Direct photolysis and H2O2-assisted photolysis showed a pseudo-first-order kinetics, while the Fenton and the photo-Fenton processes fit second-order kinetics. The provided experiments proved a high resistance of FAM to direct photolysis. Its stability depends highly on the pH of the reaction solutions. The rate of FAM direct photolysis in acidic solutions was almost negligible. The reaction rate of FAM photolysis at pH 8–9 was 3.7 × 10?3 min?1 with DT50 about 3 h 7 min. It was found that the presence of H2O2 in the reaction environment enhances the rate of photolysis of FAM. The observed rates of reaction were 5.1 × 10?3 min?1 and 3.7 × 10?3 min?1 in acidic and basic solutions, respectively. The used Fenton systems appeared to be the most efficient in FAM removal. The rate of reaction depends on concentration of Fe2+ and H2O2. It was observed that the presence of UV-light enhances the reaction rate by two to six times in comparison to the classical Fenton system. Additionally, FAM behavior in natural water under solar irradiation was examined. The irradiation experiments were carried out in batch experiments with simulated sunlight.  相似文献   
152.

Background

The Cefic Mixtures Industry Ad-hoc Team (MIAT) has investigated how risks from combined exposures can be effectively identified and managed using concepts proposed in recent regulatory guidance, new advances in risk assessment, and lessons learned from a Cefic-sponsored case study of mixture exposures.

Results

A series of tools were created that include: a decision tree, a system for grouping exposures, and a graphical tool (the MCR-HI plot). The decision tree allows the division of combined exposures into different groups, exposures where one or more individual components are a concern, exposures that are of low concern, and exposures that are a concern for combined effects but not for the effects of individual chemicals. These tools efficiently use available data, identify critical data gaps for combined assessments, and prioritize which chemicals require detailed toxicity information. The tools can be used to address multiple human health endpoints and ecological effects.

Conclusion

The tools provide a useful approach for assessing risks associated with combined exposures to multiple chemicals.  相似文献   
153.
The aim of this article is to evaluate selected tourism development strategies in Poland, in the context of strategic planning, stakeholders’ participation, and sustainable development principles. A questionnaire evaluation of strategy (44 questions) was established and based on measurement scales developed and validated by other authors in earlier studies. The five authors of the study rated 37 tourism development strategies in 13 provinces, 11 cities, 5 counties, 6 municipalities, and 2 other areas. Analysis revealed that they implement paradigms of sustainable development of tourism to only a small extent. Definitely higher quality is documented for higher levels of administrative division. The highest rated domains of the tourism development strategy in the examined documents are Strategic Planning Indicators and Implementation, Monitoring, and Evaluation.  相似文献   
154.
The concept of the ‘relief-to-development continuum’ has been the subject of renewed interest in recent years. Concerned by the rise in relief budgets over the past decade and the absolute fall in development aid resources, support has been growing for the concept of developmental relief. In the context of complex political emergencies, it has been argued further that as effective development aid can reduce vulnerability to the impact of natural hazards, so it might also be used to contribute to a process of conflict prevention. In this way, the concept of the relief-development continuum has become entwined with broader discussions about the contribution of official development assistance to conflict management. Drawing on a Review of Operation Lifeline Sudan (OLS), this paper cautions against uncritical application of the concept of the continuum in complex political emergencies, and of rehabilitation in particular, in the current Sudanese context. It argues that in order to move legitimately from relief aid programming to development aid programming, three fundamental conditions must be in place: first, a minimum level of security, respect for human rights and humanitarian access. Second, empirical evidence from the field needs to demonstrate that the emergency is over. Finally, moving from relief to development aid programming is contingent on donor governments accepting the legitimacy of national governmental structures and of the rebel movements. In other words, for donor governments, moving along the continuum is in significant part determined by foreign policy considerations, not only technical ones. Consideration needs to be given to the actual and perceived legitimation of the different movements that a move to rehabilitation might be seen to imply. The paper argues that none of these conditions had been satisfied in Sudan by mid-1997. Instead of a process of normalisation paving the way to long-term development, the current situation in Sudan is better described as a chronic political emergency. In such a context, uncritical pursuit of developmental strategies may negatively affect the welfare of conflict-affected populations.  相似文献   
155.
ABSTRACT: The main factor in the location of medieval Cracow was drainage. In the 700-year history of the City, there were numerous changes in water conditions, particularly in channel network, runoff, ground water level, and ice phenomena. The most dangerous threat to surface water and ground water in Cracow in the last decades has been from industrial and municipal sewage. Currently there are no rivers that meet Drinking Water Quality standards in Cracow. The quality of the ground water has declined because of infiltration of contaminated river water, water from sewage disposal ponds, and pollution from the atmosphere and soil. Cracow does not have enough waste water plants to meet its needs. Most municipal and industrial sewage has not been treated or has been treated only partially. Because of considerable contamination of surface and ground waters in Cracow, more than half of the city's fresh water is pumped about 50 kilometers from a reservoir on the Raba River. A Polish government declaration of April 4, 1989, recognized Cracow as an area of particular protection, and directed that a number of actions be undertaken for the protection of environmental quality.  相似文献   
156.
Toxicity investigations were conducted for four pyridinium chlorides belonging to cationic surface-active substances (CSAS), which differed from each other in the numbers of methyl groups (CH(3)) in pyridinium ring.The crustacean Daphnia magna, the fish Lebistes reticulatus and the alga Scenedesmus quadricauda were chosen as biotests. Toxicity of examined preparations appeared to be very high but did not depend on their chemical structure. S. quadricauda was the most sensitive organism. Toxicity of intermediate products obtained in biological oxidation process was also examined. Biodegradation was conducted according to the "river water test". It was found that only partial degradation took place while pyridinium chlorides constituted main energy and carbon source. Presence of biodegradation intermediate products was shown on the basis of 1H NMR analysis. Intermediates were not toxic to any biotests.  相似文献   
157.
Risk assessors have devoted considerable attention to the consumption of fish in the diet of recreational and subsistence anglers, but little attention has been directed toward the percentage that wild game contributes to total protein intake for people who engage in hunting and fishing. While recall studies have limitations, the relative errors should be similar for different types of fish and game. We interviewed 454 people attending the Palmetto Sportsmen's Classic in South Carolina to determine their consumption patterns of domesticated animals, fish (both wild-caught and commercial) and wild game. The percentage of people who consumed each type of meat was: chicken (98%); beef (95%); wild-caught fish (79%); deer (79%); restaurant fish (73%); pork (71%); dove (47%); commercial fish (41%); wild turkey (40%), duck, squirrel and self-caught quail (about 25% each); restaurant quail (10%); and raccoon (11%). Although a similar proportion of white respondents and black respondents consumed wild game overall (90%), there were ethnic differences in the number of meals of wild-caught fish and game. Black respondents ate more wild-caught fish, rabbit, raccoon and squirrel, and less deer, than did white respondents. Wild-caught fish and game made up 50% of the meat and fish diet of black sportsmen, but only 32% for whites. Wild-caught fish and game were being eaten disproportionately more by low-income black respondents, while more deer was consumed by higher-income black respondents. The data suggest that managers and planners should take into account age, ethnicity and income when (1) conducting exposure assessments, (2) considering consumption patterns for wild-caught fish and game and (3) managing risk from wild-caught fish and game. The data will be especially useful to policy makers and risk managers who are designing consumption advisories, for risk communicators in identifying the target audience and for managers designing long-term stewardship for sites with contamination.  相似文献   
158.
Many government agencies and other organizations hold large tracts of surplus land. Some are investigating ways to lower expenses by selling the land or transferring management responsibility. There is no generally recognized process used to decide what land can be decommissioned and what future use would be best. This paper provides guidance for land‐use decisions in the form of a checklist. The checklist questions address both the socio‐economic resources and current land use in the region, and the ecological resources and suitability of the tract itself. The answers will clarify regional public needs and the economic and ecological values of the land.  相似文献   
159.
A “multi-pollutant exposure programme” reflecting the new pollution situation where SO2 is no longer the dominating pollutant has been performed by the International Co-operative Programme on Effects on Materials, including Historic and Cultural Monuments (ICP Materials) within the activities of the Convention on Long-range Transboundary Air Pollution. The main results obtained in the period 1997–2003 are summarised. Dose-response functions are presented for carbon steel, zinc, copper, bronze and limestone. Parameters involved in the functions include besides SO2 and pH, which were included in the previously developed functions from ICP Materials, also the effect of particulate matter and HNO3.  相似文献   
160.
A survey of 1351 people who lived within 50 miles of one of six US Department of Energy nuclear weapon sites showed that the vast majority of residents prefer strong public health surveillance and land use controls. The sample was stratified so that the same number of responses was obtained at each site. The strongest correlates of wanting the DOE to restrict on-site activities and maintain and expand its surveillance programs were worries about DOE activities on the site, as well as how those activities could damage the off-site environment. Notably, the exceptions, that is, those who demanded less from the DOE and were not particularly worried about the DOE's activities, tended to live near the site, many worked there or knew people who did, and had high socio-economic status, and trusted the DOE. The findings are mostly, but not entirely, consistent with expectations drawn from the risk perception and organizational trust literatures. The challenge is how to establish a stewardship program that represents a consensus among state and local government, community advisory boards and the public that remediation can go on at the same time that some waste is managed on-site until suitable technologies can be safely deployed, which at some sites means 100 years or in perpetuity.  相似文献   
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