Kinetics and mechanism of oxidation of tetrachloroethylene with permanganate

The kinetics, reaction pathways and product distribution of oxidation of tetrachloroethylene (PCE) by potassium permanganate (KMnO4) were studied in phosphate-buffered solutions under constant pH, isothermal, completely mixed and zero headspace conditions. Experimental results indicate that the reaction is first-order with respect to both PCE and KMnO4 and has an activation energy of 9.3+/-0.9 kcal/mol. The second-order rate constant at 20 degrees C is 0.035+/-0.004 M(-1) s(-1), and is independent of pH and ionic strength (I) over a range of pH 3-10 and I approximately 0-0.2 M, respectively. The PCE-KMnO4 reaction may proceed through further oxidation and/or hydrolysis reaction pathways, greatly influenced by the acidity of the solution, to yield CO2(g), oxalic acid, formic acid and glycolic acid. Under acidic conditions (e.g., pH 3), the further oxidation pathway will dominate and PCE tends to be directly mineralized into CO2 and chloride. Under neutral (e.g., pH 7) and alkaline conditions (e.g., pH 10), the hydroxylation pathway dominates the reaction and PCE is primarily transformed into oxalic acid prior to complete PCE mineralization. Moreover, all chlorine atoms in PCE are rapidly liberated during the reaction and the rate of chloride production is very close to the rate of PCE degradation.     

Assessing national sustainable development strategies: Strengthening the links to operational policy

At the Earth Summit in Rio de Janeiro in 1992, it was agreed that all countries should develop a national sustainable develop‐ment strategy (NSDS) as a key component of implementing the goals of Agenda 21. Progress has been limited. Few countries have established a formal strategy, and many of the strategies that exist have been only partially implemented. This article proposes an approach that addresses the need to improve existing strategic planning mechanisms. The approach is based on a periodic assessment of existing systems, to evaluate the extent to which they incorporate NSDS principles, and identify areas to be strengthened. The article describes an assessment methodology, presents examples of its use, and discusses ways in which current approaches to NSDS may be complemented by continual review and improvement of existing planning processes.     

The use and abuse of scientific studies

In response to Evelyn Pluhar'sWho Can Be Morally Obligated to Be a Vegetarian? in this journal issue, the author has read all of Pluhar's citations for the accuracy of her claims and had these read by an independent nutritionist. Detailed analysis of Pluhar's argument shows that she attempts to make her case by consistent misappropriation of the findings and conclusions of the studies she cites. Pluhar makes sweeping generalizations from scanty data, ignores causal explanations given by scientists, equates hypothesis with fact, draws false cause conclusions from studies, and in one case claims a conclusion opposite of what the scientist published. Such poor reasoning cannot be the basis of an argument for moral vegetarianism. A broader search of the literature and attention to reviews and textbooks in nutrition shows that each of Pluhar's claims is suspect or incorrect. Pluhar has not undermined my central claims: even if animals have certain rights and well-planned vegetarian diets are safe in complex industrialized societies, these diets cannot be so regarded if the presuppositions of high levels of wealth, education, and medical care do not exist; and, women, children, the aged and some ill persons are at greater risk on restrictive vegan diets. Thus, any duty of moral vegetarianism is not categorical but provisional in nature.     

Kodak's framework and assessment tool for implementing TQEM

Total Quality Management provides a powerful management foundation and framework to implement an organization's environmental vision and principles. The elements of TQM include customer/stakeholder focus, a high degree of senior management commitment, a long-term focus, and tools such as continuous improvement, empowerment, and a prevention-based approach. This article describes a matrix developed by major U.S. and Canadian firms that serves as (1) a guide to organizations implementing TQEM from the ground floor up and (2) an assessment tool that can be used internally or externally to measure progress toward environmental management excellence and to identify opportunities for improvement. The matrix is based on categories adapted from those used in the Malcolm Baldrige National Quality Award process. The relationship between individual matrix cell criteria and key concepts such as pollution prevention and sustainability is also described.     

ADAPTATION TO ARIDITY: WATER DEVELOPMENT IN SOUTH AFRICA1

ABSTRACT The Republic of South Africa, legatee of a three-century history of recurring drought, is firmly committed to a program of the optimum use of its water for the national benefit. Its water law encourages centralized planning in that water is held to be the property of the state and is assignable without requiring acquiescence by the basin or province of origin. Interbasin diversions from the Tugela River to the Vaal River Basin, from the Orange River to the Fish and Sundays River Basins, and from several basins to Cape Town are under construction as are facilities for water importation from Lesotho and Angola. For satisfaction of demands beyond the year 2000 the nation may depend increasingly on a shift of its power production and water-using industry from the coal fields of the central plateau to nuclear power development with associated desalination along its coasts. Alternatively, and preferably, it may cooperate in a co-prosperity bloc in Southern Africa aiding the economies of its neighbors by development for mutual advantage of the water and power resources of the Okavango and other northern rivers.