Plume Rise Determination-A New Technique Without Equations

Information on plume rise is important in determining the resulting concentrations of a pollutant on the ground. Practical use of plume rise values may be made in connection with stack design, the use of urban air pollution models, and in evaluating the hazards to a population complex.

This paper presents a new equationless technique for estimating plume rise as well as a comparison of seventeen commonly used plume rise formulas. Data from 10 sets of experiments, involving 615 observations and 26 different stacks, were used to study the relation between plume rise and related meteorological and stack parameters.

An independent data set was used to test the derived methods for determining plume rise. These data were obtained by Bringfelt of Sweden and contained measurements from stacks smaller than that at the Argonne National Laboratory to those approaching the TVA stacks.

A significant improvement in the prediction of plume rise from meteorological and stack parameters resulted from the use of a new technique called the Tabulation Prediction Technique. This is a method whereby an estimate of the value of a dependent variable may be obtained from information on the independent variables. Combinations of the independent variables—wind speed, heat emission rate, momentum rate, and stability—are arranged in an ordered sequence. For each combination of independent variables, the cumulative percentile frequency distribution of the dependent variable based on past measurements is given along with other statistics such as the mean, standard deviation, and interquartile range, i.e., the difference in plume rise between the 75th and 25th percentile values. Thus, one may look up the combination of independent variables just as one looks up words in a dictionary to obtain the percentile frequency distribution of the dependent variable. The mean, for each combination of independent variables may be considered as the best estimate for the given conditions.     

Industrial Pollution Prevention! A Critical Review

Abstract

Pyrolytic product distribution rates and pyrolysis behavior of tire-derived fuels (TDF) were investigated using thermogravimetric analyzer (TGA) techniques. A TGA was designed and built to investigate the behavior and products of pyrolysis of typical TDF specimens. The fundamental knowledge of TGA analysis and principal fuel analysis are applied in this study. Thermogravimetry of the degradation temperature of the TDF confirms the overall decomposition rate of the volatile products during the depolymerization reaction. The principal fuel analysis (proximate and ultimate analysis) of the pyrolytic char products show the correlation of volatilization into the gas and liquid phases and the existence of fixed carbon and other compounds that remain as a solid char. The kinetic parameters were calculated using least square with minimizing sum of error square technique. The results show that the average kinetic parameters of TDF are the activation energy, E = 1322 ± 244 kJ/mol, a pre-exponential constant of A = 2.06 ± 3.47 × 10¹⁰ min^?1, and a reaction order n = 1.62 ± 0.31. The model-predicted rate equations agree with the experimental data. The overall TDF weight conversion represents the carbon weight conversion in the sample.     

Error orientation questionnaire (EOQ): reliability,validity, and different language equivalence

An Error Orientation Questionnaire (EOQ) was developed, consisting of eight scales on attitudes to and on coping with errors at work. In Study I (representative sample of a German city, N=478) six scales were developed with the help of a confirmatory factor analysis using LISREL techniques. They comprise error competence, learning from errors, error risk taking, error strain, error anticipation, covering up errors. All constructs were validated. In a second study, items were added to the scales and two additional scales, ‘error communication’ and ‘thinking about errors’, were included. The scales were translated into English and Dutch and 160 students in the Netherlands filled out both language versions (Study II). The 8‐factor solutions in English and Dutch were replicated. The issue of language equivalence of these two language versions were taken up (equivalence across correlations exists). Potentially biasing variables did not influence the solutions. Practical uses of the EOQ are pointed out. Copyright © 1999 John Wiley & Sons, Ltd.     

An evaluation of the performance of multiple passive diffusion devices for indoor air sampling of VOCs

The United States Environmental Protection Agency is considering recommending longer‐term sampling to achieve more accurate time‐weighted‐average detections for indoor air monitoring of volatile organic chemicals. The purpose of the research presented herein was to compare longer sampling times using passive diffusion samplers to the results from shorter‐term testing periods using sorbent tubes and low‐flow pumps (US EPA Method TO‐17) at great frequency for trichloroethene (TCE) in indoor air. A controlled release of TCE in a large room allowed for over two‐orders‐of‐magnitude daily concentration variability over the course of the two‐week monitoring event. The daily concentration measurements by US EPA Method TO‐17 and the passive diffusion samplers were performed in triplicate and had excellent reproducibility. The results of daily tests were averaged and compared with four passive diffusion devices exposed to indoor air for three, seven, ten, and fourteen days in accordance with ASTM D6196‐02. A specific uptake rate for each of the passive devices at the four different time intervals and the statistical significance of the time‐varying uptake rates were evaluated. The performance of each passive diffusion device was determined using a statistical performance criterion. The average concentration for all of the exposure periods could be reliably predicted using the established uptake rates for two of the four passive devices. © 2009 Wiley Periodicals, Inc.     

Impact of crude oil price volatility on economic activities: An empirical investigation in the Thai economy

This paper empirically examines the impact of oil price volatility on key macroeconomic indicators of Thailand. Following Andersen et al. [2004. Analytical evaluation of volatility forecasts. International Economic Review 45(4), 1079–1110], quarterly oil price volatility is measured by using the realized volatility (RV). The impact of the oil price volatility is investigated using the vector auto-regression (VAR) system. The Granger causality test, impulse response functions, and variance decomposition show that oil price volatility has significant impact on macroeconomic indicators, such as unemployment and investment, over the period from 1993Q1 to 2006Q4. Perron's [1997. Further evidence on breaking trend functions in macroeconomic variables. Journal of Econometrics 80(2), 355–385] test identifies structural breaks in all the concerned variables during the time of the Asian Financial Crisis (1997–1998). A VAR for the post-crisis period shows that the impact of oil price volatility is transmitted to budget deficit. The floating exchange rate regime introduced after the crisis may be the key contributor to this new channel of impact.     

Re-evaluation of the conformational structure of sulfadiazine species using NMR and ab initio DFT studies and its implication on sorption and degradation

In the environment, the sorption and the degradation of organic pollutants are of increasing interest. The investigation of the chemical structures provides a basis for the development of a suitable binding model approach and for the mechanistic understanding of the chemical fate processes. The aim of this study was the identification of different species of the antibiotic compound sulfadiazine (SDZ) using (1)H and (13)C NMR experiments and ab initio density functional theory (DFT) calculations. In the neutral, aprotic solvent dimethylsulfoxide-d(6) (DMSO-d(6)), a new sulfadiazine structure containing an O-H-N hydrogen bond was identified. In the protic solvent water-d(2) and in dependence on pH and the position of the amidogen hydrogen atom nine possible SDZ conformations were analyzed and five structures were identified. Good conformity between theory and calculation of (1)H NMR was observed. Unfortunately, (13)C NMR is not sensitive enough for comparison and differentiation. In order to verify the identified structures, additional NBO/NLMO (natural localized molecular orbital) analyses were conducted (calculation of net atomic charges, bond polarity, atomic valence, and electron delocalization). Finally, conformation optimizations were performed in order to investigate the stability of the SDZ species. We showed that SDZ contains no S=O double bond, but that it has two S-O single bonds. Surprisingly, negative charges were observed at the pyrimidine nitrogen atom. With these results, the known structure of SDZ was revised. Studies of the geometrical structure and the torsion angles showed that SDZ is very flexible and can be easily fitted to the sorbent. These observations would explain the strong sorbance and hence the rapid formation of non-extractable residues in the environment because SDZ acts as a strong ligand. These results show that that the sulfonamide hydrogen is important for the biological activity but the pyrimidine nitrogen and the sulfonamide oxygen is responsible for the sorbance in environment.     

Visibility and Mass Concentration in a Nonurban Environment

Considerable interest is currently directed toward atmospheric visibility and its relationship to particle size and mass concentration. Previous work has been limited to heavily polluted urban areas, and visibility studies have not included particle size characterization. An air sampling program was carried out in a nonurban, low pollution area to relate: (a) total particulate mass concentration measured with a high-volume sampler, (b) particulate mass size distribution measured with aerodynamic size selective samplers, and (c) visual range measured by the integrating nephelometer. For low suspended particulate mass concentrations, the following relationship was defined between visual range (L_v) and mass concentration (M ? μg/m³):     

Short Term Air Quality Standards for Suspended Particulate Matter in New York State

The Clean Air Act of 1970 requires each state to submit plans for implementation, maintenance, and enforcement of national ambient air quality standards subsequent to promulgation. Such plans have been geared to meet annual averages and maximum values. Based on experience in implementing the abatement plan it was found that air quality standards for averaging times shorter than one year are needed to shorten the time required to show contravention and to provide a basis for early corrective measures to regulate specific sources. This paper reports on the need and procedures used by New York State to develop such standards for suspended particulates. Daily suspended particulate data were analyzed by the Kolmogorov-Smirnov method goodness of fit technique to determine that the form of the distribution was log normal. A method developed by Larsen for predicting short term maximum concentrations for log normally distributed data was used to determine numerical values for one, two, and three month standards. Monthly, bi-monthly, and tri-monthly suspended particulate standards of 130, 110, and 100 µg/m³, respectively are proposed for the most extensively developed areas of New York State and correspondingly lower values for other areas. The methods used in this development are generally applicable to other air contaminants.     

Development,local livelihoods,and vulnerabilities to global environmental change in the South American Dry Andes

Climate change will increasingly impact large areas of South America, affecting important natural resources and people’s livelihoods. These impacts will make rural people disproportionately more vulnerable, given their dependency on ecosystem services and their exposure to other stressors, such as new rules imposed by agribusiness and trends toward the commodification of natural resources. This paper focuses on the vulnerability of rural communities in Andean drylands of Argentina, Bolivia, and Chile, showing how different economic and political pathways lead to different levels of vulnerability. The paper begins with a brief discussion of the methodological and theoretical concept of vulnerability, which framed the research. Starting from the premise that global environmental change impacts are strongly linked to styles of development, the discussion explores the diverse institutional capital and governance schemes as well as different development styles in the case studies and their role in increasing or reducing local vulnerability to climate and water scarcity. Using a comparative perspective, the exposures and adaptive capacities of rural actors in three river basins are discussed, emphasizing situations that speak for the ways in which development styles counteract or magnify conditions of vulnerability. The analysis considers irrigated and non-irrigated agriculture, water property interests, different productive structures (viticulture, horticulture, etc.), producer typologies (large/small, export, etc.), and geographical location. Finally, the paper offers some insights about development style and adaptive capacities of rural people to overcome those vulnerabilities.