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The purpose of this study to investigate acetaminophen (ACT) degradation efficiencies by using ozone/persulfate oxidation process in a batch reactor. In addition, the effects of various parameters on the ACT removal efficiency toward pathway inference of ACT degradation were investigated.

The experiments were in the 2 L glass vessels. Ozone gas with flow rate at 70 L.h⁻¹ was produced by ozone generator. After the adjustment of the pH, various dosages of persulfate (1, 3, 5, 7 and 9 mmol.L⁻¹) were then added to the 500 mL ACT-containing solution with 150 mg.L⁻¹ of concentration. Afterward, ozone gas was diffused in glass vessels. The solution after reaction flowed into the storage tank for the detection. The investigated parameters included pH and the amount of ozone and persulfate addition. For comparison of the ACT degradation efficiency, ozone/persulfate, ozone and persulfate oxidation in reactor was carried out. The ACT concentration using a HPLC system equipped with 2998 PDA detector was determined at an absorbance of 242 nm.

ACT degradation percentage by using ozone or persulfate in the process were at 63.7% and 22.3%, respectively, whereas O₃/persulfate oxidation process achieved degradation percentage at 91.4% in 30 min. Degradation efficiency of ACT was affected by different parameter like pH and addition of ozone or persulfate, and highest degradation obtained when pH and concentrations of persulfate and ozone was 10 and 3 mmol.L⁻¹ and 60 mg.L⁻¹, respectively. O₃, OH^• and SO⁴⁻ were evidenced to be the radicals for degradation of ACT through direct and indirect oxidation. Gas chromatography–mass spectrometer analysis showed intermediates including N-(3,4-dihydroxyphenyl) formamide, hydroquinone, benzoic acid, 4-methylbenzene-1,2-diol, 4-aminophenol.

This study provided a simple and effective way for degradation of activated ACT as emerging contaminants from aqueous solution. This way was conducted to protect environment from one of the most important and abundant pharmaceutical and personal care product in aquatic environments.

There are two main innovations. One is that the novel process is performed successfully for pharmaceutical degradation. The other is that the optimized conditions are obtained. In addition, the effects of various parameters on the ACT removal efficiency toward pathway inference of ACT degradation were investigated.

The purpose of this paper is to evaluate the ozone risk introduced by the mixing air-supply mode, displacement air-supply mode and personalized air-supply mode, respectively, in commercial aircraft cabins.

In this study, a computational fluid dynamics (CFD) model of aircraft cabin has been built to study the distribution of ozone mass fraction and the ozone surface deposition rate on passenger’s face and clothes under the three different air-supply modes, respectively. The distribution of ozone mass fraction has been obtained by calculating the mass concentration of ozone in different location. The ozone surface deposition rate on passenger’s face and clothes has been calculated according to the mechanism of the reactions between ozone and squalene, which is the primary reactant in human sebum.

By comparing the three air-supply modes, it was considered that the mixing air-supply mode made lower ozone concentration and ozone surface deposition risk in most area, but this was because of the thin air distribution in cabin. The displacement air-supply mode made an uneven distribution of ozone concentration and increased absorbing ozone risk in the breathing zone. The personalized air-supply mode was proper for avoiding ozone harm and making a comfortable air environment. The air supply from the inlet on seat back could not increase the ozone surface deposition risk on passenger’s face.

This paper provides the qualitative and quantitative analysis for ozone risk to the passengers under the different air-supply modes. Findings can provide some suggestions for the designers to optimize the air-supply mode of air distribution system for reducing passengers’ discomfort caused by high-altitude ozone introduction, such as breathing in too much ozone.

The study of air pollution in Saudi Arabia is not only very important at local level; it may also provide an improved understanding of air pollution problems in other arid regions throughout the world. A comprehensive field study of atmospheric ozone pollutants was conducted in Jiddah, Saudi Arabia (one of the fastest growing cities in the world) for the period 1984 to 1987. Ozone trends have been developed for five stations in Jiddah. Daily, monthly and annual means, maximum and mean maximum are reported. Average ozone concentration for these four years is given. A slight decrease in ozone concentration from 1984 to 1987 was observed. The observed reduction in the pollutant′s concentration during 1985‐87 was attributed to the implementation of motor vehicle periodical inspection (MVPI). Background information for air quality standards and the statistical significance of data are discussed. Analysis of data shows a lower mean than any international air quality standard.

The purpose of this study is to investigate forecast models using data provided by the Texas Commission on Environmental Quality (TCEQ) to monitor and develop forecast models for air quality management.

The models used in this research are the LDF (Fisher Linear Discriminant Function), QDF (Quadratic Discriminant Function), REGF (Regression Function), BPNN (Backprop Neural Network), and the RBFN (Radial Basis Function Network). The data used for model evaluations span a 12‐year period from 1990 to 2002. A control chart of the data is also examined for possible shifts in the distribution of ozone present in the Houston atmosphere during this time period.

Results of this research reveal variables that are significantly related to the ozone problem in the Houston area.

Models developed in this paper may assist air quality managers in modeling and forecasting ozone formations using meteorological variables.

This is the first study that has extensively compared the efficiency of LDF, QDF, REGF, BPNN and RBFN forecast models used for tracking air quality. Prior studies have evaluated Neural Networks, ARIMA and regression models.

The flux residues on almost all soldered printed circuit boards are removed using the chlorofluorocarbon (CFC) 113. In just one year's time production of this solvent will almost certainly be curtailed, on a scale agreed internationally. This is a major issue that needs to be addressed urgently by the electronics assembly industry worldwide. This paper presents (i) the background that has led to the restrictions being placed on production and consumption of solvent 113, (ii) the international agreement and timetable for the implementation of the restrictions and (iii) the perceived opportunities that are available to the electronics assembly industry to meet this challenge.

The “Montreal protocol on substances that deplete the ozone layer” obliges industrial countries to reimburse developing countries ‐ through new and additional resources ‐ all agreed incremental costs incurred by them in their efforts to save the ozone layer. To this end, a multilateral fund was established in 1990. The fund’s decision‐making procedures grant developing countries the same voting powers as industrial countries ‐ an almost revolutionary precedent in North‐South relations. In this article, the work of the Multilateral Ozone Fund is being analysed, with special emphasis on the development and implementation of the notion of “all agreed incremental costs” between industrial and developing countries. Since comparable institutional settings have been stipulated in the more recent treaties on climate change and biological diversity, in the concluding section five “lessons” are drawn from ozone politics for other international environmental agreements, in particular the emerging climate regime.

An earlier paper gave the background to the rôle of chlorofluorocarbons (CFCs) in the observed depletion of the Earth's stratospheric ozone, plus details of the Montreal Protocol that restricts the production and consumption of CFCs. In this paper, recent data on both the ozone depletion and the global greenhouse warming that result from CFC emissions are given. The progress by the chemical companies to identify replacements for CFCs is also discussed.

The purpose of this study is the design, fabrication and evaluation of a miniature ozone generator using the principle of electric discharge are presented.

The device was fabricated using a low-temperature co-fired ceramics (LTCC) technology, by which a multilayered ceramic structure with integrated electrodes, buried channels and cavities in micro and millimeter scales was realized.

The developed ozone generator with the dimensions of 63.6 × 41.8 × 1.3 mm produces approximately 1 vol. % of ozone in oxygen flow of 15 ml/min, at an applied voltage of 7 kV.

A miniature ozone generator, manufactured in LTCC technology, produces high amount of ozone and more than it is described in the available references or in datasheets of commercial devices of similar size.

This paper aims to study peroxymonosulfate (PMS) activation in the ultraviolet (UV)/ozone process for toxic cyanide degradation from aqueous solution by a novel and simple method.

Photocatalytic degradation of cyanide (CN^-) was carried out using a bench-scale photoreactor. Optimization of the UV/ozone process for the highest removal of cyanide was obtained. The effect of parameters such as ozone concentration, PMS concentration, temperature, cations (Cu²⁺, Co²⁺ and Fe²⁺), cyanide concentration, anions (bicarbonate, carbonate, chloride, nitrite, nitrate and sulfate [SO42−]) and scavengers (ethanol [EtOH], humic acid, TBA and NaN₃) was investigated for CN- degradation.

Complete removal of 50 mg/L cyanide was obtained in 4 min in an ozone/UV/PMS process. The cyanide removal increased from 49.3% to 100% by adding the persulfate dosage up to 100 mg/L. The effect of various cations (II) on the cyanide degradation was enhanced in the order Cu²⁺ > Co²⁺ > Fe²⁺. Hydroxyl radical based on different radical quenchers such as salicylic acid proved as the main oxidizing radical for oxidation. The application of ozone/UV/PMS to treat wastewater containing cyanide shows high degradation efficiency.

The ozone/UV/PMS system could be a process for degradation and detoxification of cyanide.

This study provided a simple and effective method for degradation of cyanide from aqueous solution. This method was applicable to protect environment from a huge amount of toxic cyanide wastewater produced by different industrial processes.

The PMS activation is done via a simple and effective method, which is carried out with the ozone/UV system. There are two main innovations. One is that the novel catalytic role of bimetallic ions in the ozone reaction with cyanide and the further decomposition of intermediate products is investigated. The other is that the optimized conditions were obtained for the removal of cyanide as a water contaminant. Furthermore, predominant oxidizing species by PMS activation are identified.

The objective of this study is to develop and validate a neural‐based modelling methodology applicable to site‐specific short‐ and medium‐term ozone concentration forecasting. A novel modelling technique utilizing two feed forward artificial neural networks (FFNN) is developed to improve the performance of time series predictions.

Air pollution and meteorological data were collected for one year in two locations in Kuwait. The hourly averages of the data were processed to generate a covariance matrix and analyzed to generate the principal component method. A two‐FFNN model is then used to predict the actual data.

The newly developed model improves the prediction accuracy over the conventional method. Owing to the presence of noise and other minor disturbances in the data, shorter‐range modelling gives better modelling results.

A novel modelling technique is developed to predict the time series of zone concentration.