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This paper aims to focus on the basic principle of WO₃ gas sensors to achieve high gas-sensing performance with good stability and repeatability. Metal oxide-based gas sensors are widely used for monitoring toxic gas leakages in the environment, industries and households. For better livelihood and a healthy environment, it is extremely helpful to have sensors with higher accuracy and improved sensing features.

In the present review, the authors focus on recent synthesis methods of WO₃-based gas sensors to enhance sensing features towards toxic gases.

This work has proved that the synthesis method led to provide different morphologies of nanostructured WO₃-based material in turn to improve gas sensing performance along with its sensing mechanism.

In this work, the authors reviewed challenges and possibilities associated with the nanostructured WO₃-based gas sensors to trace toxic gases such as ammonia, H₂S and NO₂ for future research.

The purpose of this paper is to investigate the use of Pinus wood waste in lead adsorption as a remediation technique in aqueous medium and its subsequent use in obtaining synthesis gas.

The capacity of the timber in the lead adsorption was studied in aqueous medium at various pH, determining the amount adsorbed in equilibrium. Then, the same timber was added in a fixed bed, co-current flow of two stage gasifier type, working temperature of 900°C, for obtaining synthesis gas. The synthesis gas composition was evaluated by the spectrophotometry in the infrared region and the gas chromatography and lead content in the ash and gas was determined by the atomic absorption spectrophotometry.

In laboratory tests carried out, the optimal pH for lead removal was pH 4 with 96.15 percent removal rate, reaching equilibrium after 180 min. In pilot scale the lead removal after 72 hours was 96 percent. The average production of syngas was 11.09 m³h⁻¹. For tests with the motor-generator, the best condition occurred with charge of 2.0 kW, wherein gas consumption per kW produced reached 4.86 m³ kW⁻¹, resulting in a 14.81 percent efficiency rate. The gas analysis showed an average concentration of 14.85 percent H₂, 30.1 percent CO₂, and 50.49 percent of atmospheric air. The concentration of lead in the gas was below the limit established by law. Pinus elliottii waste proved to be an excellent adsorbent, with removing more than 96 percent of the Pb ion present in aqueous solution and a starting material in the gasifier to generate synthesis gas.

This paper describes the waste wood application in the treatment of contaminated environments and for obtaining syngas providing a sustainable process.

This paper shows a process that combines the remediation of contaminated environmental with power generation systems, allowing efficient management of contaminated environments.

The petroleum shortage of the 1970s (1984 is the tenth anniversary of the OPEC embargo!) motivated tremendous interest in finding alternative raw materials for chemicals. Indeed, in 1975 it was predicted that by 1990, huge and expensive coal gasifiers would be producing CO and hydrogen for synthesis gas, from which the chemical industry would derive many of its raw materials. In 1983 it was apparent that this prediction was far from accurate. To be sure, eventually there will be a shift from petroleum to coal, but it most surely will not be before the end of the century and perhaps not even then. Coal will, however, continue to find increasing use as an energy source. The vast amount of research that has been done on converting synthesis gas to chemicals will continue, although with considerably less intensity. When the time comes, the shift will be made. But that time will be delayed as far as possible because the shift will require tremendous capital investment. Coal gasifiers can cost as much as US$500,000, and the return on such an investment must be assured before it is made. Certainly, coal is a cheap raw material. Thus, its use for chemicals represents a trade‐off between a cheap raw material and a very high capital investment.

Sensing technology has been extensively researched and used due to its applications in industrial production and daily life. Due to inherent limitations of conventional silicon-based technology, researchers are now-a-days paying more attention to flexible electronics to design low-cost, high-sensitivity devices. This observational and analytical study aims to emphasis on carbon monoxide gas sensor. This review also focuses the challenges faced by flexible devices, offers the most recent research on paper-based gas sensors and pays special focus on various sensing materials and fabrication techniques.

To get the better insight into opportunities for future improvement, a number of research papers based on sensors were studied and realized the need to design carbon monoxide gas sensor. A number of parameters were then gone through to decide the flexibility parameter to be considered for design purposes. This review also focuses on the challenges faced by flexible devices and how they can be overcome.

It has been shown that carbon monoxide gas, being most contaminated gas, needs to be fabricated to sense low concentration at room temperature, considering flexibility as an important parameter. Regarding this parameter, some tests must be done to test whether the structure sustains or degrades after bending. The parameters required to perform bending are also described.

Due to inherent limitations of conventional silicon-based technology, now-a-days attention is paid towards flexible electronics to design low-cost, high-sensitivity devices. A number of research articles are provided in the literature concerning gas sensing for different applications using several sensing principles. This study aims to provide a comprehensive overview of recent developments in carbon monoxide gas sensors along with the design possibilities for flexible paper-based gas sensors. All the aspects have been taken into consideration for the fabrication, starting with paper characterization techniques, various sensing materials, manufacturing methodologies, challenges in the fabrication of flexible devices and effects of bending and humidity on the sensing performance.

The purpose of the article is to identify relevant criteria for decision support in the implementation of waste-to-energy (WtE)-based systems.

The methodology is a simple case study with a qualitative approach. Five experts involved in the project of a thermoelectric power plant qualitatively evaluated, on a Likert scale, a decision model with 15 indicators derived from recent studies. The research object was the first stage of a project to implement a thermoelectric plant employing municipal solid waste (MSW) in southern Brazil.

The study identified 15 criteria supporting the decision-making process regarding WtE implementation for MSW in a mid-sized city in southern Brazil. The study identified that compliance with MSW legislation, compliance with energy legislation, initial investment and public health impact are the most influential criteria. The study offered two models for decision processes: a simplified one and a complete one, with ten and fifteen indicators, respectively.

The study concerns mid-sized municipalities in southern Brazil.

Municipal public managers have now a methodology based on qualitative evaluation that admits multiple perspectives, such as technical, economic, environmental and social, to support decision-making processes on WtE technologies for MSW.

MSW management initiatives can yield jobs and revenues for vulnerable populations and provide a correct destination for MSW, mainly in developing countries.

The main originality is that now municipal public decision-makers have a structured model based on four constructs (technical, economic, environmental and social) deployed in 15 indicators to support decision-making processes involving WtE and MSW management.

The purpose of this paper is to apply Foresight methodology to the area of nanotechnologies and new materials within the framework of Russian S&T Foresight 2030 aimed at revelation of major trends, most promising products and technologies.

To achieve this goal, best international practice was analyzed that provided a solid basis for Russian S&T Foresight 2030 (section “Nanotechnology and new materials”). The study used a wide range of advanced Foresight methods adapted to Russian circumstances. During the Foresight study, the authors integrated “market pull” and research “technology push” approaches including both traditional methods (priority-setting, roadmaps, global challenges analysis) and relatively new approaches (horizon scanning, weak signals, wild cards, etc.).

Using the methods of the Foresight, the authors identified trends with the greatest impact on the sphere of nanotechnology and new materials, promising markets, product groups and potential areas of demand for Russian innovation technologies and developments in this field. The authors assessed the state-of-the-art of the domestic research in the area of nanotechnologies and new materials to identify “white spots”, as well as parity zone and leadership, which can be the basis for integration into international alliances and positioning of Russia as a center of global technological development in this field.

The results of applying Foresight methodology toward revelation of the most prospective S&T areas in the field of nanotechnologies and new materials can be used by a variety of stakeholders including federal and regional authorities, technology platforms and innovation and industrial clusters, leading universities and scientific organizations in formulation of their research and strategic agenda. Russian businesses including both large companies and small and medium-sized enterprises can use results of the study in creating their strategic R&D programs and finding appropriate partners.

This paper proposes an integrated methodology for process design to guide decision making under uncertainty by combining life cycle assessment (LCA) with multi‐criteria decision‐making tools.

Cleaner and greener technologies for process and product selection and design have gained popularity in recent years. The LCA is a systematic approach that enables selection of cleaner and greener products and processes. Recently, significant progress has been made for the use of LCA for product/process evaluation and selection. However, its use in process design and environmental decision making has not been fully exploited. The proposed methodology GreenPro‐I is a systematic approach to estimate environmental risks/impacts associated with life cycle of products, processes and services. It evaluates environmental burdens by quantifying energy and materials used and waste released into the environment. It identifies and evaluates opportunities, which affect environmental improvements. The assessment includes the extraction/excavation and processing of raw materials, manufacturing, transportation and distribution, use, recycle, and final disposal.

GreenPro‐I overcomes many of the problems faced in the conventional approaches and establishes a link between the environmental risks/impacts, cost, and technical feasibility of processes.

GreenPro‐I provides a comprehensive decision‐making tool for designers, regulatory agencies, business organizations and other stakeholders.

Major hazard installations (MHIs) are dealing with hazardous substances which exceed the threshold quantity. MHIs are characterized by tight coupling and high complexity. Due to their complexity, MHIs require well trained managers who have good experience at all levels to manage the operations successfully. The managements of major hazard installations play a vital role in the success or failure of their installation. The world has witnessed many incidents in major hazard installations due to failure of the management at all levels. This paper summarizes in brief the management errors for several incidents which occurred worldwide. Also, the paper reviews the management errors which led to an incident at a petrochemical plant in East Malaysia.

Major hazard organizations are dealing with hazardous material exceeding the threshold quantity. Major hazard organizations are relatively secure areas and cannot fail from single error. However, failure of an organization to control hazardous material usually results in a technological man‐made disaster. The conditions preceding the onset of technological man‐made disaster are collectively called the technological man‐made disaster precondition phase “incubation period”. A model has been developed representing the technological man‐made disaster pre‐condition phase where it focuses on the origin of the technological man‐made disaster. The model was based on detailed analysis of four technological man‐made disasters at major hazard installations in Malaysia.

Carbon dioxide (CO₂) has attracted special scientific interest over the last years mainly because of its relation to climate change and indoor air quality. Except for this, CO₂ can be used as an indicator of food freshness, patients’ clinical state and fire detection. Therefore, the accurate monitoring and controlling of CO₂ levels are imperative. The development of highly sensitive, selective and reliable sensors that can efficiently distinguish CO₂ in various conditions of temperature, humidity and other gases’ interference is the subject of intensive research with chemi-resistive zinc oxide (ZnO)-based sensors holding a privileged position. Several ZnO nanostructures have been used in sensing applications because of their versatile features. However, the deficient selectivity and long-term stability remain major concerns, especially when operating at room temperature. This study aims to encompass an extensive study of CO₂ chemi-resistive sensors based on ZnO, introducing the most significant advances of recent years and the best strategies for enhancing ZnO sensing properties.

An overview of the different ZnO nanostructures used for CO₂ sensing and their synthesis methods is presented, focusing on the parameters that highly affect the sensing mechanism and, thus, the performance of CO₂ sensors.

The selectivity and sensitivity of ZnO sensors can be enhanced by adjusting various parameters during their synthesis and by doping or treating ZnO with suitable materials.

This paper summarises the advances in the rapidly evolving field of CO₂ sensing by ZnO sensors and provides research directions for optimised sensors in the future.