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1.
Heliyon ; 10(8): e29512, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38699753

ABSTRACT

The incorporation of intermittent renewable energy sources into a consistently controlled power transmission system hinges on advancements in energy storage technologies. Sodium ion batteries (SIBs) are emerging as a primary and viable alternative material due to their electrochemical activity, presenting a potential replacement for the next generation of lithium-ion battery (LIB) energy storage materials. However, this transition may necessitate significant alterations in the anode material, given the incompatibility of the current anode with sodium ions and the electrolyte. This review provides a comprehensive summary of various anode materials employed in SIBs, categorized according to their storage mechanisms. Additionally, it explores the growing focus on utilizing hard carbon as an anode material, driven by factors such as its relatively high specific capacity compared to graphite, cost-effective production, and eco-friendly properties as it can be derived from biomass. The review further addresses recent progress in hard carbon, detailing production methods, modifications, challenges, limitations in integrating hard carbon into the anode of SIBs, and suggests potential directions for future research.

2.
Article in English | MEDLINE | ID: mdl-38568305

ABSTRACT

Hydrogen (H2) represents a promising avenue for reducing carbon emissions in energy systems. However, achieving its widespread adoption requires more effective and scalable synthesis methods. Herein, we investigated the isothermal carburization process of the MoO3 catalyst. This reaction was carried out at a constant temperature of 700 °C in a 60% CO/He stream, with hold reaction times varying (60-min, 90-min, and 120-min). This investigation was conducted using a micro-reactor Autochem with the aim of enhancing the yield of H2. The study focused on evaluating the chemical reduction and carburization behavior of the MoO3 catalyst through X-ray diffraction (XRD), transmission electron microscopy (TEM), and CHNS elemental analysis. The XRD analysis revealed the formation of carbides, Mo2C, and MoO2, serving as active sites for subsequent H2 production in the thermochemical water splitting (TWS) process. The carburization at a 60-min hold time exhibited enhanced H2 production, generating approximately ~ 6.60 µmol of H2 with a yield of up to ~ 32.90% and a conversion rate of ~ 54.83%. This finding emphasizes the essential role played by the formation of carbides, particularly Mo2C, in the carburization process, contributing significantly to the facilitation of H2 production. These carbides serve as exceptionally active catalytic sites that actively promote the generation of hydrogen. This study underscores that the optimized duration of catalyst exposure is a key factor influencing the successful carburization of MoO3 catalysts. This emphasizes how important carbide species are to increasing H2 efficiency. Additionally, it is noted that carbon formation on the MoO3 active sites can act as a potential poison to the catalysts, leading to rapid deactivation after prolonged exposure to the CO precursor.

3.
Heliyon ; 10(4): e25993, 2024 Feb 29.
Article in English | MEDLINE | ID: mdl-38380021

ABSTRACT

Nitrocellulose (NC) has garnered significant interest among researchers due to its versatile applications, contingent upon the degree of nitration that modifies the cellulose structure. For instance, NC with a high nitrogen content, exceeding 12.5%, finds utility as a key ingredient in propellant formulations, while variants with lower nitrogen content prove suitable for a range of other applications, including the formulation of printing inks, varnishes, and coatings. This communication aims to present the outcomes of our efforts to optimize the nitration reaction of bacterial cellulose to produce high-nitrogen-content NC, employing the response surface methodology (RSM). Our investigation delves into the influence of the mole ratio of sulfuric and nitric acids, reaction temperature, and nitration duration on the nitrogen content of the resultant products. Utilizing a central composite design (CCD), we identified the optimal conditions for NC synthesis. Analysis of variance (ANOVA) underscored the substantial impact of these reaction conditions on the percentage of nitrogen content (%N) yield. By implementing the predicted optimal conditions-namely, a H2SO4:HNO3 mole ratio of 3:1, a reaction temperature of 35 °C, and a reaction period of 22 min-we successfully produced NC with a nitrogen content of 12.64%. Characterization of these products encompassed elemental analysis, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermal gravimetric analysis (TGA), and field emission scanning electron microscopy (FESEM).

4.
Polymers (Basel) ; 13(19)2021 Sep 24.
Article in English | MEDLINE | ID: mdl-34641067

ABSTRACT

The wide availability and diversity of dangerous microbes poses a considerable problem for health professionals and in the development of new healthcare products. Numerous studies have been conducted to develop membrane filters that have antibacterial properties to solve this problem. Without proper protective filter equipment, healthcare providers, essential workers, and the general public are exposed to the risk of infection. A combination of nanotechnology and biosorption is expected to offer a new and greener approach to improve the usefulness of polysaccharides as an advanced membrane filtration material. Nanocellulose is among the emerging materials of this century and several studies have proven its use in filtering microbes. Its high specific surface area enables the adsorption of various microbial species, and its innate porosity can separate various molecules and retain microbial objects. Besides this, the presence of an abundant OH groups in nanocellulose grants its unique surface modification, which can increase its filtration efficiency through the formation of affinity interactions toward microbes. In this review, an update of the most relevant uses of nanocellulose as a new class of membrane filters against microbes is outlined. Key advancements in surface modifications of nanocellulose to enhance its rejection mechanism are also critically discussed. To the best of our knowledge, this is the first review focusing on the development of nanocellulose as a membrane filter against microbes.

5.
RSC Adv ; 11(13): 7347-7368, 2021 Feb 10.
Article in English | MEDLINE | ID: mdl-35423275

ABSTRACT

Chemical contaminants such as heavy metals, dyes, and organic oils seriously affect the environment and threaten human health. About 2 million tons of waste is released every day into the water system. Heavy metals are the largest contributor which cover about 31% of the total composition of water contaminants. Every day, approximately 14 000 people die due to environmental exposure to selected chemicals. Removal of these contaminants down to safe levels is expensive, high energy and unsustainable by current approaches such as oxidation, biodegradation, photocatalysis, precipitation, reverse osmosis and adsorption. A combination of biosorption and nanotechnology offers a new way to remediate these chemical contaminants. Nanostructured materials are proven to have higher adsorption capacities than the same material in its larger-scale form. Nanocellulose is very promising as a high-performance bioadsorbent due to its interesting characteristics of high adsorption capacity, high mechanical strength, hydrophilic surface chemistry, renewability and biodegradability. It has been proven to have higher adsorption capacity and better binding affinity than other similar materials at the macroscale. The high specific surface area and abundance of hydroxyl groups within lead to the possible functionalization of this material for decontamination purposes. Several research papers have shown the effectiveness of nanocellulose in the remediation of chemical contaminants. This review aims to provide an overview of the most recent developments regarding nanocellulose as an adsorbent for chemical contamination remediation. Recent advancements regarding the modification of nanocellulose to enhance its adsorption efficiency towards heavy metals, dyes and organic oils were highlighted. Moreover, the desorption capability and environmental issue related to every developed nanocellulose-based adsorbent were also tackled.

6.
RSC Adv ; 10(8): 4465-4489, 2020 Jan 24.
Article in English | MEDLINE | ID: mdl-35495228

ABSTRACT

Organophosphorus (OP) compounds are highly toxic synthetic compounds which have been used as pesticides and developed as warfare nerve agents. They represent a threat to both military and civilian populations. OP pesticides affect the nervous system and are thought to have caused at least 5 million deaths since their discovery in the 1930s. At present the treatment of OP nerve agent poisoning commonly involves the use of parenteral oximes. However, the blood brain barrier (BBB) remains a challenge in the delivery of oximes to the central nervous system (CNS). This is because almost all macromolecule drugs (including oximes) fail to pass through the BBB to reach the CNS structures. The presence of a permanent cationic charge in oximes has made these compounds inefficient in crossing the BBB. Thus, oximes are unable to reactivate acetylcholinesterase (AChE) in the CNS. Using current structural and mechanistic understanding of the BBB under both physiological and pathological conditions, it becomes possible to design delivery systems for oximes and other drugs that are able to cross the BBB effectively. This review summarises the recent strategies in the development of oximes which are capable of crossing the BBB to treat OP poisoning. Several new developments using oximes are reviewed along with their advantages and disadvantages. This review could be beneficial for future directions in the development of oxime and other drug delivery systems into the CNS.

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