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We report for the first time the utilization of a highly invasive weed Antigonon leptopus in synthesizing gold nanoparticles. For this purpose, aqueous extracts of the weed's leaves/stem/roots served the dual purpose of reducing gold ions to uncharged metal nanoparticles and then capping the nanoparticles thus formed to stabilize them. The synthesis occurs very swiftly leading to spherical, hexagonal, or triangular nanoparticles. The influence of the key variables that control the shape/size of the gold nanoparticles (AuNPs)—concentrations of the extract relative to Au (III), temperature, interaction time, stirring, and pH-was studied employing UV–visible spectrophotometry, scanning electron microscopy, transmission electron microscopy, energy dispersive analysis of X-rays, dynamic light scattering (DLS), X-ray diffraction, and Fourier transform infrared spectroscopy. Besides being simple and rapid, the present process is distinguished by its ability to gainfully utilize an otherwise harmful plant in a manner which consumes little energy and generates no waste emissions. The AuNPs were found to catalyze the degradation of organic pollutants Congo red and Remazol Brilliant Blue R. © 2015 American Institute of Chemical Engineers Environ Prog, 2015

1. Oussudu lake is a large, shallow wetland situated close to the city of Pondicherry, India. The lake harbours rich flora and fauna, and has been recognized as one of the important wetlands of Asia by the International Union for Conservation of Nature and Natural Resources (IUCN). 2. This paper summarizes the results of a 5-year study on the annual composition, richness, diversity and population density of the bird community at Oussudu. A GIS database was developed on the basis of field surveys and allied studies. 3. The study reveals a declining trend in the number and diversity of the birds found at Oussudu with the exception of herons, egrets, plovers and lapwings. A relationship appears to exist between this decline in bird diversity and an increase in illegal fishing, cattle grazing, encroachments and pollution. These factors may have contributed to the decline of food and shelter for the birds. 4. A strategy has been developed for the conservation and management of the Oussudu catchment which would help in reversing undesirable trends. Copyright © 2003 John Wiley & Sons, Ltd.

Risk assessment is an essential prelude to the development of accident prevention strategies in any chemical process industry. But, the high costs and time involved in conducting risk assessment by conventional techniques often becomes a deterrent. In order to circumvent this problem, the authors have developed a risk analysis methodology based on a set of reliable rapid techniques and tools. The suitability of the methodology, named by us ORA (Optimal Risk Analysis), has been demonstrated by applying it to a real-life situation.

Fertilizer industries are among the chemical process industries where hazardous chemicals are handled and accidents involving heat/mass/momentum transfer can result in explosions, fires, and toxic releases. Based on experience gained from past incidents in the fertilizer industries risk assessment tools and techniques are often employed in order to identify hazards and to forecast potential disasters. These efforts have almost always focused on single events or “stand alone” accidents. The interaction of an accident with other hazardous units with the potential to cause secondary, tertiary, or higher order accidents is seldom studied. Yet, chain of accidents have been occurring in the past and the probability of a repetition in the future constantly increases because of the proximity of industrial plants and the increasing population pressure in most countries. Consequently we have developed models and computer-automated tools to study chain of accidents or “domino effects.” In this paper we discuss the concept of domino effect in the context of our methodologies, and present an illustrative case study of a major fertilizer industry situated near the city of Chennai(Madras, India).

A methodology has been developed to conduct probabilistic fault tree analysis during risk assessment in chemical process industries. The methodology is based on a system involving (a) development of fault tree, (b) determination of minimum cutsets or shortest pathways leading from initiating events (malfunctioning) to the top event (the major accident), (c) probability analysis, and (d) working out improvement index values. To this end techniques of Boolean algebra, structure moduling, analytical method of cutsets finding (top-to-bottom algorithm), Monte-Carlo simulation, optimization technique and fuzzy probability set have been used. We named the methodology Analytical -Simulation Methodology (ASM) and we developed a software package PROFAT (PRObabilistic fault tree analysis) to facilitate the use of the methodology in a rapid and eflective, yet user-friendly manner. PROFAT enables the user to find out, in an industry, (i) initiating events which may eventually lead to a major accideizt, (ii) shortest routes (minimum cutsets) a series of initiating events may take place while aiding each other in causing the accideizt. (iii) the probabilities of occurrence of such initintirig events, (iv) relative contributiom of each of the initiating events and, finally, (v) identfiing initiating events with the greatest potential to cause the top event (major accident) so that accident prevention strategies aud emergency preparedness plans can be focused on them. The noteworthy attributes of the system are: resilience towards lack of precision in the basic data, swift processing with moderate requirements of computation cupacity (sophistication of computers needed), ease of use, and direct1y utiliz-able output. The applicability of PROFAT has been denionstrated with a case study of a sulfolane manufacturing unit.

The world's most destructive industrial accident of the current decade, in terms of human lives lost (over 60) and damage to property (over $15 million), occurred at the petroleum refinery of Hindustan Petroleum Corporation Limited (HPCL) at Vishakhapatnam, India, on September 14, 1997. In this paper we have used two computer automated tools recently developed by us, MAXCRED [7], and DOMIFFECT [8], to determine their ability to forecast the details of the incident. When the situation at Vishakhapatnam, prior to the accident, was studied with MAXCRED for potential accidents and their likely consequences, the tool was able to generate a scenario which forecast the incident quite closey. We then used MAXCRED and DOMIFFECT to tell us what else might have occurred. The prognosis is quite scary. The computer tools reveal a few lucky breaks: had the situation and the events conspired a little more treacherously, the HPCL disaster would have been much larger in magnitude. Indeed the incident could have resulted in a death toll of the magnitude of the Bhopal Gas Tragedy with additional massive damage to propert. This paper show-cases the usefulness of MAXCRED and DOMIFFECT and also brings forth lessons which all industries would benefit from learning.

In the risk assessment parlance, especially with reference to chemical process industries, the term “domino effect” is used to denote “chain of accidents,” or situations when a fire/explosion/missile/toxic load generated by an accident in one unit in an industry causes secondary and higher order accidents in other units. The multi-accident catastrophe which occurred in a refinery at Vishakhapatnam, India, on September 14, 1997, claiming 60 lives and causing damages to property worth over Rs 600 million, is the most recent example of the damage potential of domino effect. But, even as the domino effect has been documented since 1947, very little attention has been paid towards modeling this phenomena. In this paper we have provided a conceptual framework based on sets of appropriate models to forecast domino effects, and assess their likely magnitudes and adverse impacts, while conducting risk assessment in a chemical process industry. The utilizability of the framework has been illustrated with a case study.

Risk analysis in chemical process industries is an elaborate exercise involving several steps from preliminary hazard identification to development of credible accident scenarios, to preparation of strategies for prevention or control of damage. All this requires substantial inputs of time and money. In order to get an approximate yet workable assessment of risk at much lesser costs, indices have been developed which link typical findings of elaborate risk analysis to scales of risk. The scales, in turn, provide workable measures of hazards/risks/safety. In the past, indices have been reported for swift risk assessment—the noteworthy among them include Dow fire and explosion index, Mond fire, explosion and toxicity index, IFAL index, and mortality index. A few rapid ranking techniques have also been proposed. This paper presents a new system of methodologies for Hazard Identification and Ranking (HIRA). The system consists of two indices: one for fire and explosion hazards and another for the hazard due to likely release of toxic chemical. The magnitudes of these indices indicate the severity of the likely accident; in terms of the size of the impacted area. HIRA has been applied to a typical chemical process industry—a sulfolane plant—and its performance has been compared with that of the Dow's and the Mond's indices. The study reveals that HIRA is more sensitive and accurate than the other indices.

Risk assessment, based on quantitative maximum credible accident analysis (MCAA), has been conducted for a chloralkali industry situated in the midst of densely populated coastal villages. The study has made use of a software package MAXimum CREDible accident analysis version 2 (henceforth referred to as MAXCRED-II) recently developed by us. Among the six different most credible accident scenarios developed using MAXCRED-II, the one envisaging ‘confined vapor cloud explosion followed by fire ball’ (in the hydrogen storage vessel) comes out to be the worst in terms of the highest propensity for damage (overpressure, missile, heat load). It also has the potential of causing domino effect (chain of accidents). The scenario of causing domino effect (chain of accidents). The scenario of ‘continuous release of chlorine from storage vessel’ is the second most disastrous, in terms of lethal toxic load likely over a large distance (3252 meters). In summary, the study reveals that given the masses of materials stored, and the conditions in which they are stored, there is a live risk of accidents in the storage vessels that would have far-reaching consequences. The industry thus poses a great risk to large areas of surrounding including densely populated villages (particularly Chinnakalapet and Kalapet) and the campuses of Pondicherry University and Pondicherry Engineering College. This paper demonstrates the utilizability of MAXCRED-II and also focuses attention on the need to bestow greater effort towards risk assessment. It is hoped that these studies will make plant managers conscious of the serious consequences that can result from accidents in their vulnerable units. Appreciation of the risk, we hope, will prompt them to develop accident prevention strategies and to put in position emergency preparedness plans to cushion the adverse impacts if accidents do occur.

Thermodynamic ionization constants of sixteen hydroxamic acids at 25 °C and 35 °C in aqueous solution and the corresponding ΔH° (standard enthalpy change) are presented.