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This paper investigates how carbon taxes affect emissions by examining British Columbia's revenue-neutral carbon tax in the manufacturing sector. We theoretically demonstrate that carbon taxes can achieve emission reductions while increasing production. Recycling carbon tax revenues to lower corporate income tax rates encourages investments, allowing plants to emit less per unit of output. Using detailed confidential plant-level data, we evaluate this theoretical prediction by exploiting the treatment intensity through plants' emission intensity. We find that the carbon tax lowers emissions by 4 percent. Furthermore, we find that the policy had a positive output effect and negative emission intensity effect, suggesting that the carbon tax encouraged plants to produce more with less energy. We provide initial evidence showing how a revenue-neutral carbon tax may achieve emission reductions while stimulating the economy.

Chemical sensors that can detect volatile organic compounds (VOCs) are the subject of extensive research efforts. Among various sensing technologies, molecularly imprinted polymers (MIPs) are regarded as a highly promising option for their detection with many advantageous properties, e.g., specific binding-site for template molecules, high recognition specificity, ease of preparation, and chemical stability. This review covers recent advances in the sensing application of MIPs toward various types of VOCs (e.g., aliphatic and aromatic compounds). Particular emphasis has been placed on multiple approaches to the synthesis of MIP-based VOC sensors in association with their performance and sensing mechanisms. Current challenges and opportunities for new VOC-sensing applications are also discussed based on MIP technology.

The demand for the development of new techniques for the use and storage of renewable energy has grown steadily due to rapid industrialization, high energy consumption, and the grave consequences of increasing greenhouse gas emissions (e.g., global warming and climate change). One of the most applicable techniques for the storage of thermal energy (obtained from renewable resources) is the application of phase change materials (PCMs). Because of their high tailorability, the use of polyurethanes (PUs) is recognized as a preferable option in the fabrication of high efficiency energy storage devices to achieve desired phase change characteristics. Therefore, this review focuses on the recent development, thermophysical properties, and applications of phase change PUs in storing thermal energy. In addition, the discussion was extended to describe the diverse strategies (like structural modification and nanocomposite formulation) used to improve the thermal energy storage characteristics of PUs, the applicability of PUs as an encapsulating material, their current limitations, and the future challenges of this research field.

Present study reports a facile synthesis of surface-active antimicrobial hyperbranched polyurethane coatings using oleo-ethers of boric acid (BA) as branching and biocidal moiety (BHPU). The antimicrobial branching center was synthesized via polycondensation reaction of BA and vegetable oil-based diol. The structural characterization of synthesized BHPU and its linear counterpart was investigated using Fourier-transform infrared (FTIR) and nuclear magnetic resonance (1H, 13C, and 11B NMR) spectroscopy techniques. The cured coatings were examined by physico-mechanical, thermogravimetric (TG) analysis and differential scanning calorimetry (DSC). The antimicrobial behavior of these polymers against Gram-positive and Gram-negative bacteria was carried out by well diffusion technique. The appearance of zone of inhibition (ZOI) in case of BHPU confirmed its antimicrobial activity, which arisen due to the presence of cationic moiety in its structure. These investigations showed that the utilization of oleo-ethers of BA as branching agent in synthesis of BHPU coatings induced prominent effect on its physico-mechanical, thermal, and biocidal properties. In addition, soil burial study for 210 days was conducted on BHPU film to confirm its contact-killing mechanism against soil-borne bacteria. These results suggest the potential scope of BHPU in various applications such as long-term antimicrobial surface-active coatings for medical devices, packaging industry, paints, etc. Keywords: Boric acid, Hyperbranched, Polyurethane, Antimicrobial coating, Sustainable polymers

Mycotoxin is toxic secondary metabolite formed by certain filamentous fungi. This toxic compound can enter the food chain through contamination of food (e.g., by colonization of toxigenic fungi on food). In light of the growing concerns on the health hazards posed by mycotoxins, it is desirable to develop reliable analytical tools for their detection in food products in both sensitive and efficient manner. For this purpose, the potential utility of molecularly imprinted polymers (MIPs) has been explored due to their meritful properties (e.g., large number of tailor-made binding sites, sensitive template molecules, high recognition specificity, and structure predictability). This review addresses the recent advances in the application of MIPs toward the sensing of various mycotoxins (e.g., aflatoxins and patulin) along with their fabrication strategies. Then, performance evaluation is made for various types of MIP- and non-MIP-based sensing platforms built for the listed target mycotoxins in terms of quality assurance such as limit of detection (LOD). Further, the present challenges in the MIP-based sensing application of mycotoxins are discussed along with the future outlook in this research field.

Aluminum is a relatively inexpensive and abundant metal for the mass production of metal-organic frameworks (MOFs). Aluminum-based MOFs (Al-MOFs) have drawn a good deal of research interest due to their unique properties for diverse applications (e.g., excellent chemical and structural stability). This review has been organized to highlight the current progress achieved in the synthesis/functionalization of Al-MOF materials with the special emphasis on their sensing application, especially toward metal ion pollutants in the liquid phase. To learn more about the utility of Al-MOF-based sensing systems, their performances have been evaluated for diverse metallic components in reference to many other types of sensing systems (in terms of the key quality assurance (QA) criteria such as limit of detection (LOD)). Finally, the challenges and outlook for Al-MOF-based sensing systems are discussed to help expand their real-world applications.

The effective control on environmental pollutants is crucial for the proper management of diverse environmental systems (e.g., soil, water, and air). In this respect, the utility of various functional materials such as hyperbranched polymers (HPs) has been recognized due to their great potentil as adsorbent for the mitigation of numerous environmental pollutants. Here, we highlight the latest progress achieved in the design and construction of HPs with high adsorption potentials. We focus on adsorption mechanisms, functionalization methods, the role of functional groups in adsorption capacity, and the choice of HPs in adsorption of cationic and anionic dyes. Recent published reports are reviewed to quantify and qualify the removal efficiency of pollutants through adsorption. We also evaluate the adsorbing efficiency of the constructed HPs and compared their performance with other such systems. The utilization potential of new materials (magnetic, polar, and biological) is highlighted along with the methods needed for their preparation and/or modification (surface, end-group, and zwitterionic) for the construction of efficient adsorbing systems. Finally, the advantages and limitations of adsorbing systems are described along with the existing challenges to help establish guidelines for future research. This article is thus expected to offer new path and guidance for developing advanced HP-based adsorbents.

Herein, a facile route was employed for the construction of novel dual-functional boronated (hybrid) hyperbranched polyurethane composite (HPUC) coatings using covalently functionalized reduced graphene oxide (FRGO) as chain extender and reinforcing agent. The FRGO exhibited excellent compatibility with the boronated HPU matrix that resulted in the chemical, structural and surface transformation of FRGO-HPUC coatings. The electrochemical corrosion studies were employed to confirm the protective performance of these composite coatings. The presence of electron deficient centres (tri-coordinated B) and electron rich FRGO restricted the diffusion of electrons through the coating network, which altered the mechanism of corrosion protection. In addition, the antimicrobial surface activity of these composites were investigated to ascertain their permanent contact killing properties.

Waterborne polyurethanes (WPUs), owing to their environmental friendliness and non-flammability, are considered as a green class of materials for a wide spectrum of applications, like adhesives, co...

Inhibition of electrochemical and microbial corrosions is one of the prominent importance in both industrial and environmental applications. Therefore, we have designed a sustainable surface-active bi-functional (antimicrobial/anticorrosive) polyurethane nanocomposite (PUC) coating by means of synergistic effects of π-π interaction and in situ incorporation of graphene oxide (GO) for the first time. The PUC was synthesized using Pongamia oil, acrylic acid (to induce π-π interaction), GO (biocidal and reinforcing agent), and toluene diisocyanate (TDI) via one-pot addition polymerization. These interactions improved GO distribution, which influenced the structure and segmental dispersion within the PUC network. Further, it was observed that the properties (physical, mechanical, thermal, barrier, and adhesion) of the synthesized PUC coating were significantly improved. The electrochemical studies confirmed that upon addition of small amount of GO (0.5 wt.%) the anticorrosive behavior of PU nanocomposite coating was increased, exhibiting high corrosion potential (Ecorr= -0.179 V), low corrosion current density (Icorr = 2.3 × 10−11 A. cm-2), and enhanced impedance modulus at low frequency (|Z|0.01 Hz = 3.6 × 1010 Ω cm2) even after 21 days of immersion (5% NaCl solution). Besides, the surface activity of the PUC coating was confirmed by its strong contact-killing effect against Gram-positive and Gram-negative bacteria. Based on these results, present work provides a facile route towards the development of high-performance dual-functional coatings that may find a wider scope of applications in various industries like maritime, food, fuel and healthcare.

Bioprocessing is a natural, safe, and effective way for food manufacturers to create products such as cheese, yogurt, bread, wine, and beer. Bioprocessing uses living organisms and their components in the creation of new products. They used microbes and enzymes in bioprocessing technology provided best results under mild conditions such as neutral pH, normal atmospheric pressure, and temperatures close to room temperature. Therefore, bioprocessing can save a lot of energy in food industry—especially when they act as an alternative to heating products to high temperatures. Bioprocessing can also enhance taste and texture. Also, the microbes used in bioprocessing are biodegradable—reducing the carbon footprint of food production even further. The conventional food bioprocessing methods such as drying, fermentation, salting, and various forms of cooking, including roasting, frying, smoking, steaming, and oven baking developed the quality and flavor of the foods but they are unable to protect from microorganisms that leads to food spoilage. So, nowadays food industries focused on nanotechnology which increases the spoilage time of food. Moreover, nanotechnology showed potential applications in all aspects of food chain including storage, quality monitoring, food processing, and food packaging.

The growth and proliferation of pathogenic microbes and bacteria on various surfaces have caused an ever-increasing awareness, necessitating scientists of diverse realm to develop potential antimicrobial materials. Among various methods of prevention, the application of biocidal polymer films and coatings has played a vital role. Generally such polymers are developed by the incorporation of antimicrobial moieties within their matrices. The design and formulation of polymer nanocomposite (PNC) films and coatings with biocidal property, have gained higher interest due to the exceptional reinforcing abilities of nanomaterials compared to other biocides. From this perspective, the aim of the present chapter is to discuss the approaches used for the fabrication and processing of surface-active, selective, leaching and nonleaching antimicrobial PNCs along with their mechanism of action. The chapter also covers the importance of naturally derived precursors for the construction of eco-friendly and cost-effective antimicrobial PNCs. Further the advantages, limitations, and the future scope of such functional PNCs have been discussed.

Rapid industrialization is associated with an increased use of electronic devices, which are used in various areas such as military, engineering, medicinal, consumer sectors, etc. However, these devices have led to the formation of a new type of pollution, that is, radiofrequency interference or electromagnetic interference (EMI). This form of pollution not only results in serious health issues (to humans) but also causes malfunctioning or interference in the surrounding electrical equipment. Hence, researchers and scientists have developed different EMI shielding materials. Generally, these materials are formulated from nonbiodegradable and expensive resources, which are not desired from environmental safety and economical points of view. In view of this, the present chapter provides a brief introduction and detailed description of recent advanced techniques used in the preparation of such biodegradable EMI shielding materials. The chapter also briefly discusses the future prospects along with advantages and shortcomings associated with these materials.

The susceptibility for corrosion, poor mechanical/chemical stabilities, and adhesion of polymers under corrosive environments hamper their application as anticorrosive coatings. The microporous structure of polymers provides passage for the penetration of corrosive ions at coating–metal interface, which led to their poor serviceability. To overcome these drawbacks, advanced structural modifications such as copolymers, hybrid polymers, and polymer nanocomposites have been made. Among these, polymer nanocomposites (PNs) have enormously attracted the attentions of corrosion technologists because of their significant role in providing the enhanced service life and improved physicomechanical and anticorrosive properties. Thus, this chapter briefly discusses the history of anticorrosive PN coatings (PNCs), use of various nanofillers in polymers, processing and formulation of anticorrosive PNCs, characterization techniques, and an overview on the utilization of sustainable precursors. The advantages and shortcomings of PNCs along with the definition of technical words and future prospects have also been discussed.

Hyperbranched polymers (HPs) are a subclass of dendritic polymers, having globular and highly branched structure, containing a number of functional groups emerging from a core. The core contains more than two functional sites where the growing branches are connected, resulting in the formation of a 3D macromolecule comprising a large number of peripheral groups. Their versatile properties and facile structural modifications have attracted considerable attention of researchers. HPs have been used in various applications such as coatings, drug delivery, nanotechnology, additives, sensors, solar cells, an so forth. Thus, this review emphasizes recent structural modifications of HPs that result in enhancement of existing or newly emerging properties. In addition, these modifications have broadened the use of HPs in various advanced technologies such as biological applications, storage devices, energy convertors, catalysis, and so forth, which have not been covered in earlier reviews. Furthermore, this article...

The abatement of airborne pathogens such as bacteria, viruses, and fungi has become an important goal of air-quality management. Efficient and effective treatment techniques such as photocatalysis are essential for disinfection of airborne microorganisms. This review focuses on recent advances in the formulation and development of photocatalytic disinfection, design of efficient photocatalysts, choice of photocatalytic reactor, removal and/or disinfection mechanisms, and the role of reactive ion species. Data from recent studies are analyzed to accurately assess the efficacy of such disinfection approaches. This review also highlights the application of innovative materials in individual and combined abatement systems against airborne bacterial, viral, and fungal pathogens. We discuss the efficiency and benefits presented by such systems, address the challenges, and provide a perspective for future research.

Localization is one of the most important research subjects in terms of the wireless sensor networks (WSNs), because most of the information measured and distributed by the sensors are useful when sensors locations are well known. In this paper, a range free localization algorithm for sensor positioning is proposed. It is based on sensor distributed network model, coverage radius, hop count between each sensor and anchor, and improvement in the minimum mean square error, which computes coefficients for distance estimation between sensors and anchors. In the proposed method, the best coefficient for each hop count is computed with offline processing and Monte Carlo method. Then, these coefficients are stored in each sensor database and they are used for localization in the practical environment. Unlike some existent positioning methods, in this algorithm, it is not required to compute distance estimation coefficient by sensors. In the proposed method, it is assumed that all sensors use the omnidirectional antenna for their usual information transmission. High precision in geographical coordinate determining, less traffic load, and especially good performance in the homogeneous and non-homogeneous environment are the most important features of this algorithm. Simulation results show that the proposed algorithm has a good position determination and reduced traffic load for WSNs, as compared with some existent positioning schemes. Indeed, the proposed method improves localization precision and reduces traffic load simultaneously.

Polyurethane (PU) offers advantageous physical-chemical properties for the fabrication of smart electronic sensing devices through the selection of suitable raw materials, structural modification, modifying the soft and hard segments, changing the NCO:OH ratio, nanofiller dispersion, and chemical functionalization. Over the past few decades, PU has attracted attention as valuable media for the construction of efficient diagnostic tools with the merit of upgrading sensing capacity and selectivity. Structurally and chemically modified PU has thus been shown to influence the performance of constructed sensors, although PU is mainly used to immobilize sensing components. In the present review, we explore the applicability of PU to the production of various types of biosensors. Definitions of biosensors and a general overview of PU are presented along with descriptions on the sensing mechanisms and synthesis approaches. Modern design trends, performance features, and future prospects of various PU-based biosensors are also discussed.