Geotechnical engineering properties of incinerator ash mixes

The incineration of solid waste produces large quantities of bottom and fly ash. Landfilling has been the primary mode of disposal of these waste materials. Shortage in landfill space and the high cost of treatment have, however, prompted the search for alternative uses of these waste materials. This study presents an experimental program that was conducted to determine the engineering properties of incinerator ash mixes for use as construction materials. Incinerator ash mixes were tested as received and around optimum compacted conditions. Compaction curves, shear strength, and permeability values of fly ash, bottom ash, and their various blends were investigated. Bottom ash tends to achieve maximum dry density at much lower water content than does fly ash. The mixes displayed a change in their cohesion and friction angle values when one of the two mix components was altered or as a result of the addition of water. The permeability of bottom ash is quite comparable to that of sand. The permeability of fly ash lies in the range of those values obtained for silts and clays. A 100% bottom ash compacted at the optimum water content has a lower density value and yields a higher friction angle and cohesion values than most construction fills. This would encourage the use of bottom ash as a fill or embankment material because free drainage of water will prevent the buildup of pore water pressures.     

MULTIVARIATE ANALYSIS OF WATER QUALITY IN THE RICHIBUCTO DRAINAGE BASIN (NEW BRUNSWICK,CANADA)1

ABSTRACT: Specific conductivity, pH, dissolved oxygen, carbon, phosphorous, and nitrogen species were measured at 36 stations in the Richibucto River drainage basin, including the estuary, in New Brunswick, Canada, over the six‐year period 1996 through 2001. Each station was sampled between 1 and 26 times (mean = 7.5, standard deviation = 6.0) during the ice free seasons without regard to tide. There was significant variance among stations in most parameters. Principal component analysis (PCA) was used to identify the processes explaining the observed variance in water quality. Because of the high variability in specific conductance, stations were first grouped in a freshwater subset and an estuarine (brackish water) subset. For freshwater stations, most of the variance in water quality was explained by pH and total organic carbon, as well as high nutrient concentrations. These high nutrient concentrations, along with water salinity, which varies with flow and tides, are also important in determining water quality variability in brackish water. It is recommended that water quality parameters that were found to explain most of the variance by PCA be monitored more closely, as they are key elements in understanding the variability in water quality in the Richibucto drainage basin. Cluster analyses showed that high phosphorous and nitrate concentrations were mostly found in areas of peat runoff, tributaries receiving treated municipal effluent, and lentic zones upstream of culverts. Peat runoff was also shown to be acidic, whether it is runoff from a harvested area or a natural bog.     

Selenium and nano-selenium in plant nutrition

Selenium (Se) is a naturally occurring metalloid element which occurs nearly in all environments. Se is considered as a finite and non-renewable resource on the Earth. The common sources of Se in earth’s crust occur in association with sulfide minerals such as metal selenide, whereas it is rarely found in elemental form (Se⁰). While there is no evidence of Se need for higher plants, several reports show that when Se added at low concentrations, Se exerts beneficial effects on plant growth. Se may act as quasi-essential micronutrient through altering different physiological and biochemical traits. Thus, plants vary considerably in their physiological and biochemical response to Se. This review focusses on the physiological importance of Se forms as well as different Se fertilizers for higher plants, especially plant growth, uptake, transport, and metabolism.     

14C-Ethion residues in soybean seeds: metabolic pathway,effect of processing,bioavailability, toxicity and protective action of artichoke leaf powder towards rats

The metabolic fate of ethion labeled with ¹⁴C-at the ethyl ester groups in soybean seeds following topical application to leaves was studied. Chromatographic analysis of soybean oil revealed the presence of the parent compound together with four metabolites which were identified as ethion monooxon, ethion dioxon, O-ethyl phosphorothioate and O,O-diethyl phosphorothioate. The effect of processing on ethion residues in soybean oil was investigated. The refined oil contained small amounts of the ¹⁴C-residues originally present (37.5%). Upon feeding rats with the cake containing ethion bound residues, a substantial amount of ¹⁴C-residues was eliminated in the urine (73%), and about 6% excreted with the feces. About 5% of the radioactive residues were distributed among various organs. Mature male Wistar rats were fed on soybean seeds containing ethion residues (1.93 ppm), and on artichoke leaves powder (1% W/W) for four weeks. At the end of the experimental period, the ethion-treated group had a significantly higher alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) activity, urea, creatinine, total cholesterol (TC), triglycerides (TG), and very low density lipoprotein (VLDL) levels. The ethion-treated rats also had a lower total serum protein and albumin levels, as well as acetyl cholinesterase (AChE), catalase (CAT), and glutathione-S-transferase (GST) activity as compared with controls. Moreover, concomitant treatment with artichoke leaf powder improved, at least partially, all the biochemical parameters that were altered by ethion.     

Estimating fugitive bioaerosol releases from static compost windrows: feasibility of a portable wind tunnel approach

An assessment of the fugitive release of bioaerosols from static compost piles was conducted at a green waste composting facility in South East England; this representing the initial stage of a programme of research into the influence of process parameters on bioaerosol emission flux. Wind tunnel experiments conducted on the surface of static windrows generated specific bioaerosol emission rates (SBER2s) at ground level of between 13 and 22 x 10(3) cfu/m2/s for mesophilic actinomycetes and between 8 and 11 x 10(3)cfu/m2/s for Aspergillus fumigatus. Air dispersion modelling of these emissions using the SCREEN3 air dispersion model in area source term mode was used to generate source depletion curves downwind of the facility for comparative purposes.     

Flow control regulations to gain waste disposal self sufficiency

In a recent ruling, the U.S. Supreme Court has determined that solid waste flow control regulations are unconstitutional. Many states have established some form of flow control. As an example, the state of New Jersey has implemented a long-term plan to gain waste disposal self-sufficiency by the year 2000. The success of this plan hinges on the flow controls implemented by the state. Almost two billion U.S. dollars of debt has been incurred by the twenty-two solid waste districts in New Jersey to build the state-of-the-art facilities necessary to reach these goals. An analysis has been performed on the most recent data available of the state’s solid waste generation and management system, at a time when New Jersey must restructure its solid waste management plan. The New Jersey solid waste management model is of interest to other states. The consequences, facts, and alternatives of flow control are examined.     

The use of some plant-derived products as effective alternatives to antibiotic growth promoters in organic poultry production: a review

Environmental Science and Pollution Research - Improving poultry production, increasing poultry immunity, and reducing the disease spreading can be achieved by adding various potentially valuable...     

The Effect of Job and Environmental Factors on Job Satisfaction in Automotive Industries

A methodology was developed for diagnosing industrial work, which includes questionnaire, observation, measurements, data collection and statistical analysis. A survey was conducted to investigate the relationship between job satisfaction and factors that affect work design in 2 automotives manufacturing companies in Malaysia. A basic work design model was proposed. The aim of this model was to determine the factors that influence employees’ perception towards their work. A set of multiple-choice questionnaires was developed and data was collected by interviewing employees at a production plant. The survey focused on job and environmental factors. The results supported the proposed model and showed that job and environmental factors were significantly related to job satisfaction. They highlighted the significant influence of age, work experience and marital status on job satisfaction. Further, environmental factors, especially the surroundings, context dependence and the building’s function, also had a significant impact on job satisfaction.     

Nanocurcumin alleviates inflammation and oxidative stress in LPS-induced mastitis via activation of Nrf2 and suppressing TLR4-mediated NF-κB and HMGB1 signaling pathways in rats

Environmental Science and Pollution Research - Coliform mastitis is a worldwide serious disease of the mammary gland. Curcumin is a pleiotropic polyphenol obtained from turmeric, but it is...