Removal of nitrates from groundwater through the use of artificial wetlands

Intensive fertilizer use has led to nitrate contamination of groundwater in many areas. This article examines the possibility of removing nitrates through the construction of artificial wetlands. A pilot study conducted in Denmark has found that the method is effective and economical, at least for small waterworks, though further treatment is necessary before an acceptable microbiological water quality is attained.     

澳大利亚威维霍抽水蓄能电站

威维霍抽水蓄能电站对昆士兰电网及其业主塔朗能源公司起着重要作用。     

'Technoscience' Education: Empowering Citizens Against the Tyranny of School Science

The status quo for school science and technology is unacceptable. While the former often is required for admission to university engineering, as well as to science programmes, the latter is deemed most appropriate for less able, concrete thinkers. This situation persists, despite the fact school science tends to generate large groups of citizens who are relatively scientifically and technologically illiterate, largely as a result of its preoccupation with identifying and training potential scientists and engineers. This practice is tyrannical. It must be abandoned forthwith. A realistic alternative is a combined technology and science programme – perhaps called 'technoscience' education – that would treat science and technology as equals. Such courses may, as well, be more democratic in the sense that technological problem solving often is more natural to everyday situations that everyone may find useful, not just future scientists or engineers. A framework for combined technology and science courses is described and defended here. Originally developed through collaborative action research amongst practising teachers of science, the approach appears to be feasible, under certain – perhaps ideal – conditions. A number of changes to science and technology education may be necessary for broader implementation, not the least of which is a general retrenchment in expectations for pre-determined learning, along with adjustments to teacher education. Nevertheless, the approach is recommended because of its emphasis on: personalization, inclusion, problematization, explicitness, apprenticeship, authenticity, contextualization and freedom. This revised version was published online in July 2006 with corrections to the Cover Date.     

Substance, Form and PFI Contracts

The Private Finance Initiative (PFI) was launched by the United Kingdom Government in 1992 in order to encourage the private sector in the UK to become more involved in public sector development projects. A key theme of the initiative was that the public should receive 'value for money'. This article investigates the accounting issue as to whether or not the private or the public sector should record any property related to PFI projects on balance sheet. It argues that although both HM Treasury and the Accounting Standards Board (ASB) might agree on the accounting principles, the practical impact is that in order for related properties to stay off the public sector's balance sheet, substantial risk needs to be transferred to the private sector. As a consequence of this, the objective of providing value for money to the public may not be achieved.     

A Personal Agenda for the Next Decade

The paper sets a broad agenda touching several areas of policy. It starts from the least likely policy at this point of time, the use of the tax system for redistribution. It discusses prudent macroeconomic coordination without the strings of the Maastricht Treaty in business troughs. Regulation of financial markets, agricultural policies, and health issues are coming up on a desirable agenda of the United States, but are probably important for all countries, as are social security policy and climate change.     

Uncertainty Associated with Future Environmental Costs and the Market's Differential Response to Earnings Information

This study examines whether the uncertainty arising from a firm's exposure to future environmental costs (environmental uncertainty) affects the market's price sensitivity to reported earnings. Specifically, when environmental uncertainty is significantly high, are investors more responsive to reported earnings released by 'high-polluting' firms than reported earnings announced by 'low-polluting' firms within the same industry? The initial impact of Title IV (the acid rain provisions) of the 1990 Clean Air Act Amendments (1990 CAAA) on the US electric utility industry provides the research setting required to isolate the effects of environmental uncertainty while addressing this question. Consistent with theoretical predictions, we find that the earnings response coefficients (ERCs) of high-polluting electric utilities are significantly greater than those of their low-polluting counterparts during a predicted period of elevated environmental uncertainty. In adjoining sample years associated with lower environmental uncertainty, we observe no statistical difference in the magnitude of the ERCs between these two groups. In addition, the study's findings suggest that the magnitude of the ERC is increasing in the firm's exposure to future environmental costs, after controlling for other factors that potentially affect ERCs.     

Internal labour markets in the Australian banking industry: their nature prior to the Second World War and their recent decline

This paper uses evidence from late nineteenth-and early twentieth-century personnel records of two Australian banks to examine the nature of internal labour markets prior to the Second World War. It is argued that the industry possessed all the classic features of internal labour markets: limited ports of entry, internal promotion, long careers, and assignment of wages by well-defined rules. The paper then examines the reasons why banks adopted internal labour markets. Finally, the paper examines the recent decline of internal labour markets and examines the role of technological and social changes in this decline.     

Application of a multi-channel system for continuous monitoring and an early warning system.

A multi-channel continuous toxicity monitoring system developed in our laboratory, based on two-stage mini-bioreactors, was successfully implemented in the form of computer-based data acquisition. The multi-channel system consists of a series of a two-stage minibioreactor systems connected by a fiber optic probe to a luminometer, and uses genetically engineered bioluminescent bacteria for the detection of the potential toxicity from the soluble chemicals. This system can be stably and continuously operated due to the separation of the culture reactor from the test reactor and accomplish easy and long-term monitoring without system shut down by abrupt inflows of severe polluting chemicals. Four different recombinant bioluminescent bacteria were used in different channels so that the modes of the samples toxicities can be reasonably identified and evaluated based upon the response signature of each channel. The bioluminescent signatures were delivered from four channels by switching one at once, while the data is automatically logged to an IBM compatible computer. We also achieved the enhancement of the system through the manipulation of the dilution rate and the use of thermo-lux fusion strains. Finally, this system is now being implemented to a drinking water reservoir and river for remote sensing as an early warning system.     

Monitor-based evaluation of pollutant load from urban stormwater runoff in Beijing.

As a major pollutant source to urban receiving waters, the non-point source pollution from urban runoff needs to be well studied and effectively controlled. Based on monitoring data from urban runoff pollutant sources, this article describes a systematic estimation of total pollutant loads from the urban areas of Beijing. A numerical model was developed to quantify main pollutant loads of urban runoff in Beijing. A sub-procedure is involved in this method, in which the flush process influences both the quantity and quality of stormwater runoff. A statistics-based method was applied in computing the annual pollutant load as an output of the runoff. The proportions of pollutant from point-source and non-point sources were compared. This provides a scientific basis for proper environmental input assessment of urban stormwater pollution to receiving waters, improvement of infrastructure performance, implementation of urban stormwater management, and utilization of stormwater.