bluuebunny/crossref_metadata_2025_split huggingface dataset:
Statistics and environmental regulations
Authors: Flora Jairus D. 
Published: February 2007

AbstractStatistics has historically played a role in studying the environment. Statistics has been used in determining the presence and amount of pollution of several types as well as studying the spread and health effects of pollution. More recently the role of statistics in environmental regulation has been explicitly recognized with new regulations requiring statistical approaches to study design, data collection and analysis, and monitoring programs of various types. Two disparate approaches to statistics in regulations have been taken: performance based regulations and method based regulations. Examples of each are discussed, together with the advantages and disadvantages of each approach. The interactions among statisticians, regulators, industry, and communities involved in environmental regulations are discussed.
Trend analysis methodology for water quality time series
Authors: McLeod A. Ian , Hipel Keith W. , Bodo Byron A. 
Published: February 2007

AbstractA general trend analysis methodology is developed for detecting and modelling trends in water quality time series measured in rivers and streams. The procedure is specifically designed for use with typically ill‐behaved river quality series characterized by problematic features such as non‐normal positively skewed populations, irregularly spaced instantaneous observations, seasonal periodicities, and dependence among water quality variables and riverflows. In order to analyze these “messy” environmental data in a systematic and rigorous fashion, the overall trend analysis approach is divided into the two main categories of graphical studies and trend tests. Within these two main steps, specific graphical, parametric and nonparametric statistical techniques are utilized. Graphical methods used in the procedure include time series plots, robust regression smooths, as well as box and whisker graphs. Nonparametric techniques include the Mann‐Kendall and Kruskal‐Wallis tests. Additionally, a test based on Spearman's partial rank correlation is introduced as a means for eliminating seasonal effects when testing for the presence of a trend. The efficacy of the trend analysis methodology is explained and demonstrated by applying it to water quality time series observed in the Saugeen and Grand Rivers of Southwestern Ontario, Canada.
Evaluating the impacts of a hydro‐electric development in northern Manitoba, Canada
Authors: Shay C. T. , Shay J. M. , Johnston B. 
Published: February 2007

AbstractIn an attempt to make optimal use of the seasonal water flow of the Churchill River for hydroelectric generation, a storage basin was created utilizing Southern Indian Lake (SIL). A dam raised the lake level by 3 m. The water was diverted primarily to the Nelson River system and its hydro stations. The increased water level changed the character of SIL. Flooding inundated the forest around the lake and the biomass that was flooded began to decompose.This study has two parts. First, we develop estimates of the flooded biomass and outline some consequences of the flooding. About 4,500 metric tonnes of biomass entered the water of one small bay of SIL. Secondly, we review the project and emphasize the need for comprehensive planning involving environmental and social scientists.
On the propagation of fuzziness of data
Authors: Schnatter Sylvia 
Published: February 2007

AbstractThe object of this paper is to discuss how fuzziness of data is propagated when statistical inference for samples of non‐precise data is carried out.The method of propagation of fuzziness as introduced by Schnatter (1989) is reviewed. This method may be applied to any statistical method which leads to a result that may be expressed as a function f(x1,…,xn) of the data x1,…,xn. It is outlined that practical application of this method is equal to determining the images of a family of compact subsets of the sample space under the function f(·).An illustrative example from environmetrics is discussed. The general approach is used to formulate a fuzzy sample mean and a fuzzy valued empirical distribution function.
Application of negative binomial regression models to the analysis of quantal bioassays data
Authors: Maul A. , El‐Shaarawi A. H. , Ferard J. F. 
Published: February 2007

AbstractThe problem of developing an approach for modelling the response of an organism to chronic toxicity is discussed in this paper and illustrated by studying the toxic effect of NaBr on the reproduction process of a population of Daphnia magna. A general model is given which includes both the negative binomial and poisson distributions as special cases depending on the values of a single parameter. The steps involved in estimating the parameters of the model and testing the goodness‐of‐fit are presented. In particular the iterative solution of the estimating equations are described in detail along with the problem of setting confidence limits for model parameters. This approach is useful in the analysis of quantal bioassay data.
Inverse modelling of environmental pollution: The role of statistics
Authors: Dovì V. G. 
Published: February 2007

AbstractModelling is currently used in problems connected with the assessment of environmental impact. This class of problems is generally well defined, in that all the characteristics (such as location, strength, etc.) of potential sources of pollution are known. On the other hand, receptor analysis uses the experimental information available in the environment (such as air or water quality) to identify polluting sources. This is why they are generally called inverse problems.The reasons for the negligible amount of research effort in the application of inverse modelling is due to the ill‐posed character (i.e. lack of continuity) of the operator that describes the problem. Nevertheless, large strides have been made in the so‐called regularization of inverse operators, which makes use of additional available information.The aim of this paper is to explore how the statistical information employed in receptor analysis can be used for regularization purposes in the general inverse modelling of environmental problems.
B‐spline approximation for the baseline hazard function
Authors: Angelos James , Lee Carl M.‐S. , Singh Karan P. 
Published: February 2007

AbstractEtezadi‐Amoli and Ciampi (Biometrics 1987) introduced a method to approximate the baseline hazard and to estimate the regression coefficients for covariates simultaneously for the extended hazard regression (EHR) model using a quadratic spline approach. In this paper, an estimate of the baseline hazard function by B‐spline approximation using a minimax criterion is proposed. The nonlinear problem is approximated by a linear programming problem with only linear constraints. The nice features of this approach are: (i) the minimax criterion provides a robust approximation to the hazard function, and (ii) the linearized problem is numerically simple and fast.
Relative performance of two dust samplers: An application of robust regression
Authors: Sutradhar B. C. , Azam M. N. , Moore E. 
Published: February 2007

AbstractThe respiratory health condition of the workers in mines is affected by concentration of dust mainly deposited due to production activities. Two standard dust sampler instruments (NY and ME) were used to measure the dust concentration in two mining complexes in Labrador, Canada. The dust absorption capacity of these samplers is assumed to be influenced by temperature and humidity of the experimental environment. This paper examines the relative performance of the two dust samplers NY and ME taking the covariates temperature and humidity into account. This is achieved through a robust regression analysis by regressing the ratio of dust concentrations measured by NY and ME on temperature and humidity. Also robust regression results are compared with classical multiple regression based on the power transformation.
Inference about covariances under missing values
Authors: Provost Serge B. 
Published: February 2007

AbstractThe likelihood ratio criterion for testing the mutual independence ofqsubvectors of anl‐dimentional normal vector on the basis of a sample of sizeNonlcomponents and of an incomplete sample of sizeMonrcomponents (r < l). This is equivalent to testing the hypothesis that each variable in one subvector is uncorrelated with each variable in the other subvectors. This asymptotic distribution of the test statistic is given.
Wastewater concentration by seeded reverse osmosis: A field demonstration in the electric power industry
Authors: Hess Mary Chionis , Jones George , Micheletti Wayne , Tomlinson Joe 
Published: February 2007

AbstractWaste minimization is a key objective of power plant water/wastewater management. Even though membrane processes, such as reverse osmosis, have been used for makeup water treatment, their applications to waste minimization have been very limited. Although the field test results for a seeded reverse osmosis (SRO) system were not absolutely conclusive, the SRO system offers some unique features which may enable the utility industry to realize the advantages of membrane separation processes for wastewater concentration without extensive pretreatment and the associated costs.
Municipal solid waste composition and the behavior of metals in incinerator ashes
Authors: Clapp T. L. , Magee J. F. , Ahlert R. C. , Kosson D. S. 
Published: February 2007

AbstractDisposal of solid and hazardous wastes has become a concern in recent years. Incineration is a promising option for both, however, there are questions of public health effects and environmental acceptability of incinerator outputs. Ideally, operating conditions could be controlled to limit toxicity of residuals; to develop process models and feed‐back algorithms requires knowledge of the causal relationships between input and output to quantify induced responses.The composition of municipal solid wastes (MSW) from residential service areas was categorized and residuals from MSW incineration were examined for metal content and leachability. Sample size, sampling methodology, segregation by category and homogeneity of service area were determined to be dominant factors influencing the composition of MSW. There were notable differences in metal content of the fly and bottom ash residuals. Lead and zinc were the dominant trace metals in both ash residuals. Concentrations of cadmium and lead leached from the flyash were found to exceed EP limits. Lead and cadmium of both bottom ash and flyash fail proposed TCLP extraction limits by even larger margins. Permanent elimination of high‐temperature process ashes, classified as hazardous, must be demonstrated.
Nanofiltration extends the range of membrane filtration
Authors: Eriksson Peter 
Published: February 2007

AbstractNanofiltration is a pressure driven membrane process between reverse osmosis and ultrafiltration. The rejection is low for salts with monovalent anion and nonionized organics with molecular weight below 150 while high for salts with di‐ and multivalent anions and organics with molecular weight above 300. Examples of applications are removal of color and TOC from Florida surface water, removal of hardness, radium, and sulfate from well water, removal of sulfate from seawater and simultaneous removal of sodium chloride and concentration of organics with molecular weight 300–1000 in the food and pharmaceutical industries. The investment cost for a nanofiltration plant is about the same as for a brackish water reverse osmosis plant, but the energy savings can be considerable by using nanofiltration instead of reverse osmosis.
Low NOx, high efficiency multistaged burner: Gaseous fuel results
Authors: Srivastava Ravi K. , Mulholland James A. 
Published: February 2007

AbstractA multistaged combustion burner design is being evaluated on a 0.6 MW package boiler simulator for in‐furnace NOx control and high combustion efficiency. A low NOx precombustion chamber burner has been reduced in size by approximately a factor of two (from a 600 ms first‐stage residence time to 250 ms), and, for additional NOx control, coupled with [1] air staging, resulting in a three‐stage configuration, and [2] natural gas fuel staging, yielding up to four stoichiometric zones. Natural gas, doped with ammonia to yield a 5.8 percent fuel nitrogen content, was used to simulate a high nitrogen content fuel/waste mixture. In low NOx burner baseline tests, without advanced staging, a 315 ppm NO emission (measured dry, corrected to zero percent O2) was measured, compared with an emission of 1000 ppm measured using a conventional, unstaged burner. Both of the multistaged combustion modifications for additional NOx control reduced NO emissions by an additional 50 percent, to 160 ppm meeting the program goal. However, air staging application resulted in the entire front end of the boiler being fuel‐rich, whereas fuel staging, or reburning, in the boiler required only a small fuel‐rich flame core in the boiler. Further, no boiler penetrations were necessary with reburning modification, as staged fuel and air were injected through the boiler front wall; access for burnout air injection deep into the boiler was necessary for the air staging modification. Thus, the four‐stage configuration, combining the precombustion chamber burner and reburning, appears to be the most promising approach for minimizing NO emissions and maximizing primary fuel/waste destruction.
Identification and quantification of volatile organic species during microbial treatment of leachate
Authors: Sikkema Stephen , Dienemann Erik , Ahlert Robert , Kosson David 
Published: February 2007

AbstractSequential anaerobic/aerobic microbial populations, in a packed‐bed configuration, were employed to biodegrade leachate from a high priority Superfund site. Leachate characteristics included up to 100 ppm (as carbon) volatile organic priority pollutants. Identification and quantification of these pollutants at key steps in the biodegradation process is important. A method employing purge and trap concentration followed by gas chromatographic separation was developed for accurate identification and quantification of the volatile compounds of interest. Results obtained from application of this method to the leachate treatment process indicated that 84 to 99% of the specific volatile priority pollutants were biodegraded, under anaerobic conditions, during steady‐state operation.
The simultaneous removal of oil and heavy metals from industrial wastewater by joint precipitation and air flotation
Authors: Gopalratnam Venbakm C. , Bennett Gary F. , Peters Robert W. 
Published: February 2007

AbstractA joint precipitation and air flotation system was used to simultaneously remove oil and heavy metals from an industrial wastewater. The wastewaters were subjected to hydroxide treatment and chemical collectors simultaneously. The flotation tests were run for 4 min. For the particular wastewaters studied, the optimal pH and air injection rate was 9.18 and 12,150 cm3/min, respectively. Three different chemical collectors were investigated (WOF‐67, Nalco‐7182, and Jayfloc‐806*); the optimal collector dosage was typically in the range of 2–5 mg/L (depending on the particular chemical collector and heavy metal of concern). Removals of the heavy metals and oil typically exceeded 85%; oil removals are great as 96.2% were achieved. Removal of the heavy metals and oil probably occurred through a coprecipitation‐adsorption mechanism. Removals of the various heavy metals compared favorably between the individual removal and simultaneous removal (of heavy metals and oil) studies. By appropriate choice of the chemical collector, its dosage, pH and air injection rate, the selectivity for individual metal species can be affected.
Lamella settlers: Material balances and clarification rates
Authors: Maimoni Arturo 
Published: February 2007

AbstractWe show that material balances and clarification rates of a lamella settler can be obtained from the particle size distribution and density of the solid, the density and viscosity of the liquid, the desired concentration of solids in the overhead product, and the concentration of solids in the feed and underflow, using an algorithm based on a simple geometric model. The method was validated using concentrated suspensions (up to 20 vol% solids) of four different feed‐particle size distributions of hydrargillite (aluminum hydroxide) in water. Most of the data were obtained in a 60‐cm‐long settler with 1‐cm plate separation inclined at 60° to the horizontal in “open bottom” and “normal” configurations. The algorithm is not applicable to tube settlers, whose hydrodynamics are more complex.
Aquifer restoration: Chlorinated organics removal considerations in proven vs innovative technologies
Authors: Dworkin Daniel , Cawley Mark W. 
Published: February 2007

AbstractThe arguments over the use of proven vs. innovative technologies have gone on since the inception of the scientific and engineering communities. Currently, the discussions and interactions regarding “applicable” technology and when and where to use it focus on groundwater contamination. The need for removal of chlorinated organic compounds looms large as one of many groundwater treatment problems. Widely accepted technology keys on carbon as the solution; however, carbon is not without problems. Alternative innovative approaches include volatilization and biologic degradation. The alternatives have applicability and also certain limitations.
Treatment of a water‐reactive powder
Authors: Fochtman E. H. , Swanstrom C. , Cashen T. 
Published: February 2007

AbstractThe treatment of water‐reactive solid waste chemicals which generate corrosive products poses unique problems of feeding and reactor design. These problems have been addressed on a bench‐scale and the design of a unit suitable for hazardous waste has been developed. The water‐reactive material used was powdered titanium trichloride which was reacted with water (and oxygen) to give titanium dioxide and hydrochloric acid. The acid was neutralized by an alkaline scrubbing media.
Waste reduction: Program, practice and product in chemical manufacturing
Authors: Delcambre Ryan 
Published: February 2007

AbstractWaste Reduction has been a daily pursuit of manufacturing operations for many years. During the 1970's, as feedstocks and energy costs escalated, a renewed emphasis was placed on yield improvement and energy conservation. These improvements, in many cases, reduced the volume of unwanted byproducts that had to be managed as waste and increased the overall productivity of the manufacturing process.
Use of fly ash as a waste minimization strategy
Authors: Wentz C. A. , Moretti C. J. , Henke K. R. , Manz O. E. , Wiken K. U. 
Published: February 2007

AbstractCost‐effective liner materials for waste disposal that would meet state regulatory requirements for liner permeability while reusing coal combustion fly ash, reducing ash disposal costs were developed. Liner development criteria included a permeability of less than 10−7 cm/s and a durability comparable to that of conventional clay liners. Fly ash samples from six utility companies located in five states were used. These samples were representative of the large quantities of fly ash available from coal‐fired power plants. When mixed with 3–9.5% by weight portland cement and/or lime, each of the samples yielded liners with permeabilities significantly less than 10−7 cm/s and compression strengths generally exceeding 400 psig. Liner construction costs ranged from $0.05 to $0.44 ft [3], with the costs depending on the quantities of fly ash and additives used, formulation mixing method, and placement and compaction methods for the lifts. Studies of leachate from each fly ash found that none of them would be hazardous under current regulatory guidelines.
Source reduction technical assistance: A pilot project and its implications for the chemical industry
Authors: Dane Lee 
Published: February 2007

AbstractAs part of its developing source reduction program, the Massachusetts Department of Environmental Management (DEM) has conducted a technical assistance project with precious metals platers in the southeast region of the Commonwealth. During this project, DEM identified a number of raw material substitutions and source reduction technologies that significantly reduce both costs and volumes of hazardous waste generated. DEM suggests ways in which the chemical industry might respond to market change, and details ways in which non‐regulatory agencies can foster source reduction and encourage expanded markets for source reduction chemistries and technologies.
The effect of acid rain legislation on the economics of CO2recovery from power plants
Authors: Cobb Thomas B. , Streets David G. , Veselka Thomas D. , Wolsky Alan M. 
Published: February 2007

AbstractProposed acid rain legislation and the long‐term need to enhance domestic oil production could combine to make economic the recovery and use of SO2/CO2mixtures that are now vented to the atmosphere from the smokestacks of fossil‐fired combustors.
Removal of humic acid and toxic organic compounds by iron precipitation
Authors: Ying Wei‐Chi , Duffy James J. , Tucker Michael E. 
Published: February 2007

AbstractRemoval of humic acid is necessary to ensure efficient removal of many toxic organic compounds such as PCBs and chlorinated pesticides. Precipitation either as ferrous or ferric hydroxide is far more effective for removing humic acid than activated carbon adsorption and lime‐soda softening processes. Many recalcitrant compounds, such as HET acid, are also removed by chemisorption on newly‐formed ferric hydroxide flocs. An integrated waste treatment process consisting of iron precipitation, biodegradation, and carbon adsorption was developed for complete and efficient treatment of chemical waste landfill leachates and other highly contaminated industrial wastewaters.
Volatile organic compounds in indoor air: Types, sources, and characteristics
Authors: Gammage R. B. , Matthews T. G. 
Published: February 2007

AbstractExamples are given of occupant activities and consumer and construction products inside residences that cause transient and persistent emissions of volatile organic compounds (VOC). Transient emissions arise from window cleaning, carpet laying, smoking, and automobile operations. Persistent VOC emitters include gasoline, mothballs, and pressed‐wood products containing urea formaldehyde resins. Simple screening methods are given for making indoor measurements of VOC. Detailed laboratory and research house studies of formaldehyde emissions decay from pressed‐wood building products are described.
Biological treatment of leachate from a superfund site
Authors: Opatken Edward J. , Howard Hinton K. , Bond James J. 
Published: February 2007

AbstractStudies were made on treating a leachate from New Lyme, Ohio. The leachate was transported to Cincinnati, where a pilot‐sized rotating biological contactor (RBC) was used for a treatment evaluation. Biomass was developed on the RBC discs with primary effluent from the City of Cincinnati's Mill Creek Sewage Treatment Facility. Experiments were then conducted to determine the effectiveness of treating a hazardous waste leachate and to provide information on: the rate of organics removal; the final effluent quality; the fate of priority pollutants and specific organic compounds; and the loss of volatiles via stripping in the RBC. The results of these experiments and the applicability of an RBC to treat a hazardous waste leachate from a Superfund site are reported.