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The purpose of this study was to carry out an analysis of the corrosion failure on a chrome-moly pipeline transporting highly concentrated sulfuric acid in a demineralization section at a petrochemical plant, along with the feasibility of using inhibitors to minimize the corrosive effects of sulfuric acid.

X-ray fluorescence spectroscopy, high-resolution optical microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy and accelerated corrosion experiments (ACE) were performed.

Erosion-corrosion failure was confirmed by the significant reduction in thickness of the internal surface of the material exposed to sulfuric acid, as well as the formation of an oxide scale/layer. ACE accurately predicted high material loss from exposure to sulfuric acid. Moreover, adding ascorbic acid as a corrosion inhibitor (even at low concentrations) was found to reduce the oxidation by more than 50% in the presence of sulfuric acid.

The main idea/purpose of this work relies on the analysis of recurrent real-life corrosion-attributed failures that are common in industry but are not properly addressed for a variety of reasons, poor management and lack of corrosion preventive strategies being the main ones. This study once again highlights readily available solutions/implementations that are capable of not only addressing technically the issue investigated but also, and as important, economically. By using microscopic imaging, reliable well-tested and widely used characterization methods, all combined with basic experiments and tests, the nature of the repetitive failure investigated was clearly demonstrated as well as readily available alternatives to minimize it in the short term. Nevertheless, implementing material selection techniques appropriately as effective corrosion prevention/control and cost-saving strategies must be enforced in any process.

The increasing accumulation of synthetic plastic waste in oceans and landfills, along with the depletion of non-renewable fossil-based resources, has sparked environmental concerns and prompted the search for environmentally friendly alternatives. Biodegradable plastics derived from lignocellulosic materials are emerging as substitutes for synthetic plastics, offering significant potential to reduce landfill stress and minimise environmental impacts. This study highlights a sustainable and cost-effective solution by utilising agricultural residues and invasive plant materials as carbon substrates for the production of biopolymers, particularly polyhydroxybutyrate (PHB), through microbiological processes. Locally sourced residual materials were preferred to reduce transportation costs and ensure accessibility. The selection of suitable residue streams was based on various criteria, including strength properties, cellulose content, low ash and lignin content, affordability, non-toxicity, biocompatibility, shelf-life, mechanical and physical properties, short maturation period, antibacterial properties and compatibility with global food security. Life cycle assessments confirm that PHB dramatically lowers CO₂ emissions compared to traditional plastics, while the growing use of lignocellulosic biomass in biopolymeric applications offers renewable and readily available resources. Governments worldwide are increasingly inclined to develop comprehensive bioeconomy policies and specialised bioplastics initiatives, driven by customer acceptability and the rising demand for environmentally friendly solutions. The implications of climate change, price volatility in fossil materials, and the imperative to reduce dependence on fossil resources further contribute to the desirability of biopolymers. The study involves fermentation, turbidity measurements, extraction and purification of PHB, and the manufacturing and testing of composite biopolymers using various physical, mechanical and chemical tests.

The purpose of this paper is to develop a fuzzy analytic network process (FANP) model to select the maintenance policy of an acid manufacturing company.

Four maintenance strategies of Corrective Maintenance (CM), Time-Based Maintenance (TBM), Condition-Based Maintenance (CBM) and Shutdown Maintenance (SM) are investigated to be considered for seven equipment of the case study. These equipment are almost new and include boiler, molten sulfur ponds, cooling towers, absorption tower, converter, sulfur fuel furnace and heat exchanger. Chang’s extended analysis has been employed to deal with fuzzy data and analyze the fuzzy decision matrices. The proposed approach is applied to a sulfuric acid production plant and the suitable maintenance policy is found for all seven equipment of the company.

Based on the obtained results, the CBM policy is appropriate for high-risk (cooling tower) and high added value equipment (absorption tower). In addition, TBM is selected for boiler and converters while SM is selected for molten sulfur ponds. Finally, high-cost, low-risk and low added value equipment (sulfur fuel furnace and heat exchanger) are more appropriate with CM policy.

This research presents a novel idea to consider cost, risk and added value in the context of maintenance policy selection. From the methodological and theoretical features, this research offers new insights in this area since, to the best of the authors’ knowledge, no comparable study has been conducted before.

This paper aims to study the corrosion inhibition behavior of imidazopyridine and its three derivatives on brass.

The authors performed weight loss experiments, electrochemical experiments including the polarization curve and electrochemical impedance spectrum, corrosion morphology observation using scanning electron microscope (SEM) and atomic force microscope (AFM) and surface composition analysis via X-ray photoelectron spectroscopy (XPS) to analyze the corrosion inhibition behavior of imidazopyridine and its three derivatives on brass by using quantum chemical calculation (Gaussian 09), molecular dynamics simulation (M-S) and Langmuir adsorption isotherm.

According to the results, imidazole-pyridine and its derivatives were found to be modest or moderately mixed corrosion inhibitors; moreover, they were spontaneously adsorbed on the metal surface in a single-layer, mixed adsorption mode.

The corrosion inhibition properties of pyrazolo-[1,2-a]pyridine and its derivatives on brass in sulfuric acid solution were analyzed through weight loss and electrochemical experiments. Moreover, SEM and AFM were simultaneously used to observe the corrosion appearance. Furthermore, XPS was used to analyze the surface. Then, Gaussian 09 and M-S were combined along with the Langmuir adsorption isotherm to investigate the corrosion inhibition mechanism of imidazole-[1,2-a]pyridine and its derivatives.

With increased populations and movement of people worldwide, traffic emissions will lead to an increase in carbon dioxide emissions, which is one of the greenhouse gases. This will increase outdoor air pollution and other environmental risks that will impact people's health and livelihood, crops, as well as the built environment such as architecture, buildings and other structures. Few studies have been devoted to addressing the effect of air pollution on historic buildings. However, there is no specific study on the impact of traffic-related emissions.

A thorough analysis has been conducted in selecting eight historic districts (HDs) among all of 31 located within the city of San Antonio. Motor Vehicle Emission Simulator (MOVES) software has been utilized to process the data collected from the average annual daily traffic (AADT) and vehicle operational speeds and evaluate the amounts of emissions for each HD.

MOVES outcomes showed that HDs are under the threat of deterioration caused by traffic emissions. Therefore, transportation and environmental planners need to implement sustainable solutions to reduce the impact of CO₂ emissions on HDs and, ultimately, historic buildings.

This study will help policymakers plan a better course of action for the future conditions associated with the increased traffic volumes. It is also beneficial for the developers, preservationists, architects and all other stakeholders willing to preserve the history of a country.

To the world at large, the problems of energy supply and demand have tended to obscure the need to focus attention on what is happening in the nonfuel minerals area. But to those of us in the business, the problems are no less compelling and largely similar. Nonfuel minerals demand for the year 2000 is estimated to constitute approximately two‐thirds of total minerals demand in the United States. The U.S. Geological Survey estimates that by the year 2000 U.S. dependence on imports will be complete for 12 commodities and over 75 percent for 19 others.

Mr. LEVENSTEIN, the President of the Society of Chemical Industry, in his address delivered at Liverpool recently, dealt very fully with the question of the commercial position of Great Britain as compared with other countries, more especially Germany, and emphasised the fact that if this country is to compete successfully with her contemporaries she must, to use the words of the Prince of Wales at the Gúildhall, “wake up.” After reviewing the chief factors making for Germany's advance in industry and commerce Mr. LEVENSTEIN says: “How are we to defend ourselves? Shall we rest content as we are or bestir ourselves and awake to the irresistible fact that continued apathy and indifference mean ruin to our national position?” This is strong language but not stronger than the occasion demands, for the statistics by which these observations are backed clearly indicate a marked decadence in the national prosperity notwithstanding the years of apparent “record” trade, which, however, cannot be regarded so favourably when subjected to detailed analysis and comparison. Mr. LEVENSTEIN'S suggestions to meet this situation are as follows: (1) The appointment of a competent and expert Minister of Commerce. (2) The nationalisation and extension of our canals and waterways. (3) A measure for greatly extending and improving our secondary education. (4) A sensible reform of our patent laws.

The statements which have recently been made in various quarters to the effect that Danish butter is losing its hold on the English market, that its quality is deteriorating, and that the sale is falling off, are not a little astonishing in face of the very strong and direct evidence to the contrary furnished by the official records. As an example of the kind of assertions here alluded to may be instanced an opinion expressed by a correspondent of the British Food Journal, who, in a letter printed in the March number, stated that “My own opinion is that the Danes are steadily losing their good name for quality, owing to not using preservatives and to their new fad of pasteurising… .”

The purpose of this study is to develop laboratory techniques to evaluate the inhibition efficiency of salt neutralizer (SN) solutions in the corrosion protection of metal alloys associated with winter maintenance equipment.

The corrosion resistance of alloys A36, B36 and B152 treated with SNs was evaluated by accelerated corrosion testing (ASTM B117) and electrochemical polarization curves. Characterization of inhibition solutions was performed by contact angle measurements, scanning electron microscopy, ultraviolet-visible spectroscopy and Fourier transform infrared spectroscopy.

Salt neutralizer systems act as mixed inhibitors in acidic media by changing the corrosion resistance ability of metal alloys because of the adsorption of surfactant molecules through their hydrophilic heads. The correlation of the corrosion rate of metal alloys and the inhibitor efficiency showed the influence of the SN type, its concentration, its effective adsorption constant and its contact angle on the alloy surface. Salt neutralizers with higher manufacturer’s recommended wash concentrations (MRWC) to critical wash concentration ratio, lower contact angle on the alloy surface and higher K_eff were more successful at preventing corrosion on the alloys tested.

The results of this work provide, for the first time, both quantitative and qualitative information of the properties of washing techniques in the use of effective cleaning strategies for protecting winter maintenance equipment from corrosion. Other state departments of transportation facing similar weather conditions will be benefited by identifying measures and techniques to increase the corrosion resistance of their equipment assets.

The statement of the Minister of Agriculture, Fisheries and Food, coming so quickly after the ban on the use of cyclamates in food and drink in the United States, indicates that the new evidence of carcinogenesis in animals, placed at the disposal of the authorities by the U.S. F.D.A., has been accepted; at least, until the results of investigations being carried out in this country are available. The evidence was as new to the U.S. authorities as to our own and in the light of it, they could no longer regard the substances as in the GRAS class of food additives. It is, of course, right that any substance of which there is the slightest doubt should be removed from use; not as the result of food neuroses and health scares, but only on the basis of scientific evidence, however remote the connection. It is also right that there should always be power of selection by consumers avoidance is usually possible with other things known to be harmful, such as smoking and alcohol; in other cases, especially with chemical additives to food and drink, there must be pre‐knowledge, so that those who do not wish to consume food or drink containing such additives can ascertain from labelling those commodities which contain them.