Effect of interior door position on room-to-room differences in residential pollutant concentrations after short-term releases

Residential interior door positions influence the pollutant concentrations that result from short-term indoor sources, such as cigarettes, candles, and incense. To elucidate this influence, we reviewed past studies and conducted new experiments in three residences: a single-story 714 m³ ranch-style house, a 510 m³ two-story split-level house, and a 200 m³ two-story house. During the experiments, we released sulfur hexafluoride or carbon monoxide tracer gas over short periods (≤30 min) and measured concentrations in the source room and at least one other (receptor) room for various interior door opening positions. We found that closing a door between rooms effectively prevented transport of air pollutants, reducing the average concentration in the receptor room relative to the source room by 57–100% over exposure periods of 1–8 h. When intervening doors were partially or fully open, the reduction in average concentrations ranged from 3% to 99%, varying as a function of door opening width and the distance between source and receptor rooms.     

Nature conservation and local plans

It is noted that nature conservation has gained progressively in importance as a planning issue. The paper reports on the role of the Nature Conservancy Council, and in particular their Assistant Regional Officers, in consulting over the production of local plans. Local plan policies may assist valuably in the protection of important sites, although sympathetic planning authorities can also assist nature conservation in a variety of other ways. Sustained and systematic liaison with planning authorities is necessary for nature conservation to become a substantive local plan issue.     

FACTORS INFLUENCING ACUTE TOXICfrY OF COAL ASH TO RAINBOW TROUT (SALMO GAIRDNERI) AND BLUEGILL SUNFISH (LEPOMIS MACROCHIRUS)1

ABSTRACT: The potentially toxic components in coal ash (ash particles, heavy metals) were evaluated in laboratory static, acute (96 hr) bioassays, both separately and in various combinations with extreme pH (5.0 and 8.5), using rainbow trout (Salmo gairdneri) and bluegifi sunfish (Lepomis macrochirus). Ash particle morphology and metal distribution anlaysis, using electron microscopy and surface-subsurface analysis by ion microscopy, showed that metals could be either clumped or evenly distributed on the surface of fly ash. Surface enrichment on fly ash particles from electrostatic precipitators, as measured by ion microscopy, was found for cadmium, copper, chromium, nickel, lead, mercury, titanium, arsenic, and selenium. Bottom (heavy) ash was not acutely toxic to either fish species at concentrations of up to 1500 mg/l total suspended solids (TSS) at pH 5.0, 7.5, or 8.5. Fly ash particles were not acutely toxic to blue-gill at levels up to 1360 mg/l TSS. Rainbow trout were highly sensitive to fly ash (25 to 60 percent mortality) at concentrations of 4.3 to 20.5 mg/I TSS when dissolved metal availability was high but were not sensitive at higher particulate concentrations (58 to 638 mg/I TSS) when dissolved metals were low. When metals were acid-leached from fly ash prior to testing, no rainbow trout mortality occurred at TSS concentrations of up to 2,350 mg/l TSS. When the percent of dissolved metal was high (e.g., 50–90 percent of the total), fish mortality was increased. Rainbow trout were nearly two orders of magnitude more sensitive than bluegill when subjected to a blend of cadmium, chromium, copper, nickel, lead, and zinc. The two species were similar in their acute sensitivity to acidic pH at levels at or below 4.0 and alkaline pH of 9.1. If the pH of coal ash effluent is contained within the range 6.0 to 9.0, acute toxicity to fish can be attributed to trace element availability from fly ash but not heavy ash. Control of holding pond and effluent pH and maximizing pond residence time are important strategies for minimizing effects of ash pond discharges on fish.     

Enterprise boards: evolution and critique

There has been a marked proliferation of local economic development initiatives in recent years. Enterprise Boards have proved one of the most successful of these innovations. In the early 1980s five were established. Two, the Greater London and the West Midlands Enterprise Boards, were initially designed to intervene radically within their local economies, although subsequent events moderated their activities. The remaining three in Lancashire, West Yorkshire and Merseyside, have successfully widened their operations to embrace collaborate projects with the private sector, training, boosting co‐operatives, and research. By many economic evaluations, for example, jobs supported, leverage ratios and investment per job, Enterprise Boards have performed better than other instruments of urban and regional development. Wider socio‐political objectives have proved more difficult to achieve.     

BIOECONOMIC CONSIDERATIONS FOR WASTEWATER REUSE IN AGRICULTURAL PRODUCTION1

ABSTRACT: Urban wastewater can be a valuable source of water and plant nutrients for agricultural producers, particularly in arid regions. The scientific literature reveals cautious optimism concerning the biological, institutional, and economic viability of irrigating crops with secondary-treated effluent. A derived effluent demand function for agricultural producers near Tucson, Arizona, reveals a potential annual demand of 11,000 acre-feet under present price and proposed delivery system conditions. In this case, wastewater could be exchanged for ground water and both the urban and rural areas would gain.     

Degradation of Monophenylheptamethylcyclotetrasiloxane and 2,6-cis-Diphenylhexamethylcycloterasiloxane in Londo Soil

The natural degradation of monophenylheptamethylcyclotetrasiloxane and 2,6-cis-diphenylhexamethylcyclotetrasiloxane in soil was evaluated under laboratory conditions. Both monophenyl and 2,6-cis underwent rapid degradation in dry soil generating the same products in varying proportions. During the first 24 hr, approximately 99% of the two materials underwent significant chemical transformations forming silanols of various structures, dimethyl cyclic siloxanes of the structure (Me₂SiO)x, and rearrangement products (geometrical isomers) of diphenylhexamethylcyclotetrasiloxane. Among the silanols, the following were identified as trimethylsilyl derivatives: HOSiMe₂OH, HOSiMePhOH, HOSiMe₂OSiMe₂OH, HOSiMePhOSiMe₂OH, HOSiMePhOSiMePhOH, HOSiMe₂OSiMe₂OSiMe₂OH, HOSiMePhOSiMe₂OSiMe₂OH, HOSiMe₂OSiMePhOSiMe₂OH, HOSiMePhSiMe₂OSiMePhOH, HOSiMePhOSiMePhOSiMe₂OH, HOSiMePhOSiMe₂OSiMe₂OSiMe₂OH, HOSiMe₂OSiMePhOSiMe₂OSiMe₂OH, HOSiMePhOSiMe₂OSiMePhOSiMe₂OH, HOSiMePhOSiMePhOSiMe₂OSiMe₂OH, HOSiMePhOSiMe₂OSiMe₂OSiMePhOH, HOSiMe₂OSiMePh-OSiMePhOSiMe₂OH. Derivatization was carried out using bis(trimethylsilyl)trifluoroacetamide. Gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry (atmospheric pressure chemical ionization) analyses were used to derive structures. Structures were confirmed by gas chromatography-mass spectrometry comparisons of synthetic standards. Degradation was slower in wet soil. Nevertheless, in 14 days, the chemical transformation was essentially found to be complete as soil was allowed to dry. Detection of phenol as one of the degradation products revealed the occurrence of carbon–silicon bond cleavage promoted by soil.     

The Characterisation of Settled Dust by Scanning Electron Microscopy and Energy Dispersive X-ray Analysis

Settled dust has been collected inside the main foyers ofthree University buildings in Wolverhampton City Centre,U.K. Two of the three buildings are located in a streetcanyon used almost exclusively by heavy duty dieselvehicles. The dust was collected on adhesive carbonspectro-tabs to be in a form suitable for analysis byscanning electron microscope and energy dispersive X-rayanalysis. Using these analytical techniques, individualparticle analysis was undertaken for morphology andchemistry. Seasonal variations and variations due tolocation were observed in both the morphologicalmeasurements and chemical analysis. Many of the differencesappear attributable to the influence of road traffic, inparticular, the heavy duty diesel vehicles, travellingalong the street canyon.     

Strategic Connectivity,Sustainable Development and the New English Regional Governance

This paper examines the institutional impacts of the new English regional sustainability framework and highlights the tension between the need for regional involvement and the central desire to control the debates and intentions of the regional actors. The paper argues that the regional sustainable development frameworks have been worth writing because they have had a strong demonstration effect: they have allowed regional chambers to become more proactive bodies independent of the regional development agencies (which chambers were created to scrutinize). They have also allowed pluralistic conceptions of sustainable regional development to develop in the English regions alongside the economistic perspectives of national policy makers.     

Land Evaluation for Maize Based on Fuzzy Set and Interpolation

The objective of this article is to apply fuzzy set and interpolation techniques for land suitability evaluation for maize in Northern Ghana. Land suitability indices were computed at point observations using the Semantic Import (SI) model, whereas spatial interpolation was carried out by block kriging. Interpolated land suitability shows a high correlation (R2 = 0.87) with observed maize yield at the village level. This indicates that land suitability is closely related to maize yield in the study area. Membership functions were further used to assess the degree of limitation of land characteristics to maize. Sixty percent of the data has membership functions ranging from 0.23 for ECEC to 1.00 for drainage. ECEC, organic C, and clay are the major constraints to maize yield. The use of the fuzzy technique is helpful for land suitability evaluation, especially in applications in which subtle differences in soil quality are of a major interest. Furthermore, the use of kriging that exploits spatial variability of data is useful in producing continuous land suitability maps and in estimating uncertainties associated with predicted land suitability indices.