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Chlorine gas is a greenish-yellow gas that is one of the most utilized gases in numerous industrial fields. It has been categorized as a choking agent that can threaten human, animal, and environmental safety. Currently, development of highly sensitive, selective, and precise chlorine sensors receives much attention. This review focuses on several sensing techniques used for chlorine gas and free chlorine in water. The fundamental working principles, as well as the sensing mechanisms of chlorine detection covering spectrophotometric, electrochemical, and optical techniques, are described. A comparison of various sensing materials is also discussed. Finally, an overview of the future improvements needed of high-performance chlorine sensors was suggested.

For years, organophosphorus poisoning has been a major concern of health problems throughout the world. An estimated 200,000 acute pesticide poisoning deaths occur each year, many in developing countries. Apart from the agricultural pesticide poisoning, terrorists have used these organophosphorus compounds to attack civilian populations in some countries. Recent misuses of sarin in the Syrian conflict had been reported in 2018. Since the 1950s, the therapy to overcome this health problem is to utilize a reactivator to reactivate the inhibited acetylcholinesterase by these organophosphorus compounds. However, many questions remain unanswered regarding the efficacy and toxicity of this reactivator. Pralidoxime, MMB-4, TMB-4, obidoxime, and HI-6 are the examples of the established oximes, yet they are of insufficient effectiveness in some poisonings and only a limited spectrum of the different nerve agents and pesticides are being covered. Alternatively, an option in the treatment of organophosphorus poisoning that has been explored is through the use of enzyme therapy. Organophosphorus hydrolases are a group of enzymes that look promising for detoxifying organophosphorus compounds and have recently gained much interest. These enzymes have demonstrated remarkable protective and antidotal value against some different organophosphorus compounds in vivo in animal models. Apart from that, enzyme treatments have also been applied for decontamination purposes. In this review, the restrictions and obstacles in the therapeutic development of oximes, along with the new strategies to overcome the problems, are discussed. The emerging interest in enzyme treatment with its advantages and disadvantages is described as well.

Purification on kappa (ƙ) carrageenan was performed by dissolving ƙ-carrageenan powder in distilled water and re-precipitated with ethanol and n-hexane separately during re-precipitation process. The purified kappa carrageenan was analyzed by using Fourier transform infrared (FTIR) spectroscopy and carbon, hydrogen, nitrogen, and sulfur (CHNS) elemental analysis. The outcomes from FTIR showed there are physical changes due to intermolecular interactions which lead to decrease and lower intensity of hydroxyl band at 3345 cm-1 after re-precipitated with n-hexane, compared to re-precipitation with ethanol and unpurified ƙ-carrageenan. There were variations observed in the percentages of C, H and S in the CHNS analysis between unpurified and purified ƙ-carrageenan. The successfully purified ƙ-carrageenan are suitable to be used for further application.

Cellulose nitrate has attracted great interest amongst researchers due to its uses in wide range of products including paint and gun propellant. Therefore, this work focuses on the synthesis of cellulose nitrate from two different sources of cellulose; plant and bacterial, in order to obtain high percentage of nitrogen content hence suitable for propellant application. The synthesis of cellulose nitrate was carried out via nitration method using nata de coco and kapok (Ceiba pentadra L) as a raw materials of cellulose. The samples were then characterized by elemental analysis, fourier transform infrared (FTIR) spectroscopy, x-ray diffraction and surface electron morphology (SEM). FTIR analysis showed the presence of NO2 groups in both nitrocellulose proving that nitrocellulose was successfully synthesized by nitration method even though it was produced from different sources of cellulose. It is also showed nitrocellulose with high percentage of nitrogen content was obtained from bacterial cellulose, 12.69% rather than plant cellulose.

This study reported the preparation and characterization of gel polymer electrolyte (GPE) using poly (vinylidine fluoride-co-hexafluoropropylene) (PVdF-HFP), lithium perchlorate (LiClO4) and 1-butyl-3-metilimmidazoliumhexafluorophosphate [PF6]. The GPE were prepared by solution casting technique. [Bmim] [PF6] ionic liquid is used as an additive for the purpose of increasing the ionic conductivity of GPE. Morphological analysis showed that the electrolyte gel polymer sample had a smooth and flat surface with the addition of [Bmim] [PF6] and no phase separation effect was observed. This shows the compatibility between PVdF-HFP and [Bmim] [PF6]. ATR-FTIR analysis showed that C-F bond related peaks experienced peak changes in terms of intensity and peak shifting. This proves the interaction of the imidazolium ion with the fluorine atom through the formation of coordinate bonds. Ionic conductivity analysis showed that PVdF-HFP-[Bmim][PF6] samples reached a maximum room temperature ionic conductivity value of 2.44 × 10-4 S cm-1 at 60 wt.% [Bmim] [PF6]. When 20 wt.% of LiClO4 added to the system, the ionic conductivity increased one magnitude order to 2.20 × 10-3 S cm-1.

The cost of conventional membrane, Nafion® used in the current proton exchange membrane fuel cell (PEMFC) is high. Thus different alternatives are being proposed as an option of Nafion® membrane in PEMFC application. In this study, poly(vinyl alcohol)/ N-methylene phosphonic chitosan/ 2-hydroxyethylammonium formate (PVA/NMPC/2-HEAF) proton exchange membrane was prepared using the solution casting technique. The effects of 2-HEAF concentrations (0 – 20 wt.%) on crosslinked and non-crosslinked PVA/NMPC/2-HEAF membrane were studied. The characterizations of PVA/NMPC/2-HEAF membrane were done by Fourier transformation infrared spectroscopy (ATR-FTIR), water uptake test, ion exchange capacity (IEC) analysis and electrochemical impedance spectroscopy (EIS). The crosslinkages (-O-CH2-O-) formed using formaldehyde crosslinking agent were confirmed through the formation of new peak by –CH2- stretching at around 2863 cm-1 and the increased intensity of C-O stretching absorption. Crosslinked PVA/NMPC/5 wt.% 2-HEAF membrane showed the highest percentage of water uptake and IEC value. The EIS result agrees with the water uptake and IEC analysis where crosslinked PVA/NMPC/5 wt.% 2-HEAF showed the highest ionic conductivity of 5.44 × 10-5 S cm-1. This is due to the plasticization effect of 2-HEAF that softened the polymer chains and which it also provided more charge carriers to increase the ion mobility in the membrane.

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.

Military systems have become more complex, and the development of future advanced materials for defence applications has received much attention. Nanocellulose has been identified as a ‘super versatile material’ that will become a replacement material for many applications including in the military. Nanocellulose can be synthesized from discarded fibers that are left over from forestry and agricultural waste that can be transformed into high-value products. Thanks to its interesting properties, comprising low thermal expansion coefficient, high aspect ratio, high crystallinity, and good mechanical and optical properties, nanocellulose has emerged as a new material class for high end military products such as bulletproof vests, fire-retardant materials, as a component of propellants and filtration materials, and in textile, electronic and energy products. Therefore, in this review, current and future applications of nanocellulose in the military are critically discussed. This review is intended to impart to readers some of the excitement that currently surrounds nanocellulose research, and it's fascinating chemical and physical properties and applications in the military.

Acephate (Ac) is an organophosphate (OP) compound, which is able to inhibit the activity of acetylcholinesterase. Thus, the aim of this study was to optimize the detection of Ac using a thiolated acephate binding aptamer-citrate capped gold nanoparticle (TABA–Cit-AuNP) sensor that also incorporated an image processing technique. The effects of independent variables, such as the incubation period of TABA–Cit-AuNPs (3–24 h) for binding TABA to Cit-AuNPs, the concentration of phosphate buffer saline (PBS) (0.001–0.01 M), the concentration of thiolated acephate binding aptamer (TABA) (50–200 nM), and the concentration of magnesium sulphate (MgSO4) (1–300 mM) were investigated. A quadratic model was developed using a central composite design (CCD) from response surface methodology (RSM) to predict the sensing response to Ac. The optimum conditions such as the concentration of PBS (0.01 M), the concentration of TABA (200 nM), the incubation period of TABA–Cit-AuNPs (3 h), and the concentration of MgSO4 (1 mM) were used to produce a TABA–Cit-AuNPs sensor for the detection of Ac. Under optimal conditions, this sensor showed a detection ranging from 0.01 to 2.73 μM and a limit of detection (LOD) of 0.06 μM. Real sample analysis demonstrated this aptasensor as a good analytical method to detect Ac.

Polypyrrole (PPy) has been widely used as a sensing material in many studies as PPy gives out noticeable reactions towards varieties of vapours of acids, bases, alcohols, alkanes, and chemical warfare agent (CWA) simulants. However, due to dispersion and mechanical properties limitation, PPy in nanoparticles (PPy NPs) has been introduced. The combinations between PPy NPs and nanosized metal oxide have shown promising improvement in the sensitivity of a sensor due to the larger total surface area of detection. In this study, the potential of PPy NPs and polypyrrole-iron oxyhydroxide (PFFs) nanocomposite as sensing materials in detecting the CWA simulant, dimethyl methylphosphonate (DMMP), is investigated. PPy NPs and modified PFFs nanocomposite were successfully synthesised using chemical oxidative polymerisation. The formation of PPy NPs and the effect of iron-oxyhydroxide (FeOOH) on the chemical interaction, morphology, and size of PPy NPs were investigated using attenuated total reflection-Fourier transform infrared (ATR-FTIR), field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). ATR-FTIR analysis showed that the modified PFFs nanocomposite was successfully produced through the presence of a sharp –OH peak. The size of the prepared PPy NPs and PFFs nanocomposite was observed in the range of 50 to 70 nm and 110 to 160 nm, respectively, through TEM analysis. The electrochemical behaviour of PPy NPs and PFFs nanocomposite towards DMMP was investigated using cyclic voltammetry (CV) where, in the presence of DMMP, PPy NPs and PFFs nanocomposite showed 24% and 21% current signal reduction, respectively. This suggests that both PPy NPs and PFFs nanocomposite are able to discriminate an electrical signal both with and without the presence of DMMP.

Nitrocellulose has attracted great interest amongst researchers due to its uses in a wide range of products including paint and gun propellant. This study focuses on the synthesis of nitrocellulose from bacterial cellulose via nitration method. It is important to obtain cellulose nitrate with a high percentage of nitrogen content so that it can be used as an ingredient in propellant. The experiments were carried out at various times of reaction; 30, 60 and 90 min. The samples were then characterized by elemental analysis, Fourier transform infrared (FTIR) spectroscopy and surface electron morphology (SEM). FTIR shows the presence of NO2 groups in nitrocellulose, proving that it was successfully synthesized by nitration method. This result is supported by SEM result which demonstrates different morphologies between pure and modified cellulose. As a conclusion, the optimum reaction time obtained in synthesizing nitrocellulose is 60 min with nitrogen content of 12.1%.

This review article provides an overview of the background of nerve agents (NAs) and their hydrolysis products. The analytical techniques that are used for the analysis of hydrolysis products are also discussed. The analysis methods include the chromatographic, mass spectrometric, electrophoretic, and sensing technologies that are currently available for the detection of exposure to a number of hydrolysis products of NAs. All reviewed information was gathered through a detailed search of Scopus, PubMed, and the World Wide Web using relevant keywords, e.g., NA, hydrolysis products, and methylphosphonic acid. Most analyses of NA hydrolysis products still rely on chromatographic techniques such as gas and liquid chromatography. Analyses based on mass spectrometry are now fairly routine and can be further improved by providing analyses with precise and accurate masses and faster scan speeds that provide further gains in sensitivity. Although these techniques have high selectivity and sensitivity, most of them are rarely applied to real samples or suffer from destructive real sample analysis. In addition, there is still a lack of studies on the development of portable sensors for the detection of NA hydrolysis products. Although the analysis of NA hydrolysis products has experienced a transition from qualitative analysis toward rapid and quantitative identification, portable, and fast sensing technologies have not been well established or investigated extensively. In the future, more analysis methods are expected to be developed and may involve the development of sensors and lab-on-chip devices that should address specificity, sensitivity, stability, response time, and repeatability/reproducibility.

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 had proven its usefulness 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 that, the presence of an abundant OH groups in nanocellulose allows its 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 is 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.

The threat of the novel coronavirus (COVID-19) pandemic is worrying as millions of people suffered from this outbreak. The COVID-19 can be airborne by attaching to human nasal or saliva secretion of an infected person or suspended fine particulates in the air. Therefore, in order to minimize the risks associated with this pandemic, an efficient, robust and affordable air‐borne virus removal filters are highly demanded for prevention of spreading viruses in hospitals, transportation hubs, schools, and/or other venues with high human turn‐over. Respirators such as N95, N99 and N100 as well as surgical masks have been widely used. To date, there is no filter standards or special filter technologies tailored for effectively adsorbing the airborne viruses. Studies had shown the electrostatic fibers were capable to entrap the negatively charged viruses including COVID-19. Researchers believed that the positive surface charge of filtration material is an important key to efficiently adsorb the negatively charged viruses. Nanocellulose has emerged as a new class of biobased material with promising potential application in the filtration of viruses. Nanocellulose which is uniform in diameter and has excellent nanofibrillar morphology. To the best of our knowledge, lack of study is done to determine the efficiency of cationic nanocellulose as filtration material of COVID-19.

Conducting polymers have been widely used in electrochemical sensors as receptors of the sensing signal’s analytes and transducers. Polypyrrole (PPy) conducting polymers are highlighted due to their good electrical conductive properties, ease in preparation, and flexibility of surface characteristics. The objective of this review paper is to discuss the theoretical background of the two main types of electrochemical detection: impedimetric and voltammetric analysis. It also reviews the application and results obtained from these two electrochemical detections when utilizing PPy as a based sensing material in electrochemical sensor. Finally, related aspects in electrochemical sensor construction using PPy will also be discussed. It is anticipated that this review will provide researchers, especially those without an electrochemical analysis background, with an easy-to-understand summary of the concepts and technologies used in electrochemical sensor research, particularly those interested in utilizing PPy as a based sensing material.

The search for new compounds other than oxime as potential reactivator that is effective upon organophosphate poisoning treatments is desired. The less efficacy of oxime treatment has been the core factor. Fourteen compounds have been screened via in silico approach for their potential as sarin-inhibited human acetylcholinesterase poisoning antidotes. The selection of the compounds to be synthesized based on this computational screening, reduces the time and cost needed. To perform the docking study of sarin-inhibited acetylcholinesterase and reactivator-sarin inhibited acetylcholinesterase complexations, a bioinformatics tool was used. Estimation of the nucleophilic attack distance and binding energy of fourteen potential compounds with sarin inhibited acetylcholinesterase complexes to determine their antidote capacities was carried out using Autodock. A commercially available antidote, 2-PAM was used for the comparison. The best docked-pose was further examined with molecular dynamics simulation. Apart from being lipophilic, a compound with a carboxylic acid, (R)-Boc-nipecotic acid is shown to exhibit 6.29 kcal/mol binding energy with 8.778 Å distance of nucleophilic attack. The stability and flexibility of the sarin-inhibited acetylcholinesterase, complexed with (R)-Boc-nipecotic acid suggests this compound should be tested experimentally as a new, promising antidote for sarin-inhibited acetylcholinesterase poisoning.

This study aims to evaluate the ageing performance of Kraft and Kenaf insulation press-paper in Natural Ester (NE), which could be applied in a power transformer. Kenaf fiber was produced by Kraft pulping process is considered as potential insulation press-paper due to higher cellulose. Due to environmental concerns, NE uses have been considered an alternative to mineral oil. In this experiment, an accelerated ageing test was carried out with transformer insulation press-paper. Kraft and Kenaf press-paper were impregnated in NE with a copper strip of 90°C and 140°C for 10,20 30 days. Fourier transform infrared spectroscopy (FTIR) result showed that O-H's absorption intensity decreased, while C-H, C=O, and C-O bond increased with the ageing time. The viscosity measurements have been used to compare the stability of aged NE with Kraft and Kenaf press-paper at different ageing time. It is found that the viscosity results showed aged NE with Kraft press-paper is higher than Kenaf presspaper as the duration of ageing increase.

Solid polymer electrolytes (SPE) of poly (ethylene oxide) (PEO) - 50% epoxidized natural rubber (ENR50) polymer blend doped with lithium bis(trifluoromethanesulfonyl)imide salt (LiTFSI) have achieved an optimum ionic conductivity value of 6.45 × 10−5 S cm−1 at 25 wt % of LiTFSI salt (room temperature). The chronoamperometry analysis indicated that the charge transport in polymer electrolyte is near-dominated by ion with lithium transference numbers (TLi+) of 0.29. Notably, this electrolyte exhibits a good electrochemical stability of 4.2 V (vs. Li/Li+). Further investigation by IR has indicated that polymer-salt complexation occurred between Li+ from dopant salt with oxygen from the ether group (C-O-C). These have weaken the vibrational mode of methylene group (CH2); scissoring and rocking mode on plane as well as twisting mode for out of the plane. The strong complexation between the cations with the polymeric segments have indirectly increased the thermal stability of the polymer electrolytes. Nevertheless, using the facile blending method, the addition of environment benign and natural material of ENR50 has improved the PEO-based electrolyte system.

Innovative building approaches, which take advantage of heat energy in buildings, have recently appeared as part of a global effort to save energy. Incorporating phase change material (PCM) into the building envelope helps in reducing energy consumption and regulating energy demand by managing the thermal inertia of designed PCM thermal characteristics. A study was conducted to assess the performance benefits provided by the latent heat of the concrete wall combined with PCM. This study focuses on developing and testing heat barrier performance by incorporating PCM into wall external finishing, i.e. cement plaster and gloss paint. The effect of PCM inclusion in building wall were investigated by experimental work. The results indicate that incorporating PCM into the building wall reduced the surface temperature by up to 9 °C. Furthermore, the application of the PCM in the plaster layer is more reliable in reducing the internal wall surface temperature by a value of 8.1 °C when compared to the PCM in a painted coating. Painted wall panels experienced more significant temperature reduction differences than other wall panels, i.e. 9.2 °C and 9.5 °C, respectively. However, painted wall panels experienced higher internal surface temperatures than external surface temperatures compared to plastered wall panel at night. This could be due to the paint reactions, which are ineffective at releasing internal heat from the building at night. The yearly energy demand is decreased by 64.3% by incorporating PCM to the building wall, with a total annual electricity bill savings of 42.3% (8695.8 kWh yr−1). Therefore, it was concluded that wrapped PCM integrated into plaster layers on external surface building walls could decrease the indoor building temperature and thus contribute to conserving the energy required for an air conditioning system.

Enzymatic detection of organophosphate (OP) compounds can be tailored using highly sensitive and selective enzymes in the development of biosensors. Previously, mutant (YT) phosphotriesterase (PTE) was reported to efficiently hydrolyze Sp and Rp enantiomers of phosphotriester. This study reports the use of phosphotriesterase mutant YT (YT-PTE) immobilized onto reduced graphene oxide (rGO) and fabricated onto a screen-printed carbon electrode (SPCE) for electrochemical detection of OP compounds. Immobilization of YT-PTE onto rGO was secured using N-hydroxysuccinimide (NHS) and N-(3-dimethylaminopropyl)-N’-ethylcarbodiimide (EDC) cross-linker, and the resulting immobilized enzyme was able to retain up to 90% of its activity. Electrochemical analysis of the SPCE/rGO/YT-PTE showed detection of paraoxon in a linear range of 1 mM–0.005 μM with its limit of detection as low as 0.11 μM. SPCE/rGO/YT-PTE exhibited high selectivity towards paraoxon and parathion and have good reproducibility. Furthermore, detection of paraoxon was also possible in a real water sample with only minor interferences.

Acephate (Ac), an organophosphate (OP) insecticide, is very harmful to human and the environment. Conventional techniques of detection are sensitive and selective but relatively time-consuming, expensive, and require trained personnel. This paper describes the use of an image processing technique to digitize the red values (RVs) of the colour image of Ac-capped gold nanoparticles (Ac-Cit-AuNPs) complex captured using a digital microscope to improve the detection accuracy and precision. The formation of the suspension was characterised using laser test, ultraviolet-visible spectrophotometer (UV-Vis), high-resolution transmission electron microscope (HRTEM), and Fourier Transform infrared spectroscope (FTIR). The linear regression analysis revealed that the detection sensitivity improved as the smaller gold nanoparticles were used. For quantitative measurement using image processing, a good linear relationship (R2 = 0.9905 and 0.9924) for Cit-HAuNPs and Cit-MAuNPs, respectively, between the concentration of Ac and average red values was obtained in the range of 0–8 mM. The limit of detection (LOD) for Ac was found to be 0.3 mM and 0.4 mM for Cit-MAuNPs and Cit-HAuNPs, respectively.

The increasing energy demand on available global lithium resources has created concerns on development of new and advanced sustainable energy sources. Sodium-based batteries have emerged as promising substitutions to Li-based batteries. We describe here sodium trifluoromethanesulfonate (NaCF3SO3) electrolyte system based on tetraethylene glycol dimethyl ether (tetraglyme). The ionic conductivity of the electrolytes showed a maximum value of 1.6 mS cm−1 for 40 mol% of NaCF3SO3 at room temperature and increased up to of 9.5 mS cm−1 at 373 K. The system showed the anodic stability of the electrolytes up to ca. 5.2 V (Na+/Na) and facile deposition of sodium began at relatively low overpotential, around − 0.01 V vs. Na+/Na, which showed a good reversibility of the electrolytes. Preliminary tests of the electrolyte in half sodium-ion cells employing Na3V2(PO4)3 as cathode electrodes were performed and the cells delivered capacity of 74 mAh g−1 at C/10.

Immobilization is a method for making an enzyme more robust in the environment, especially in terms of its stability and reusability. A mutant phosphotriesterase (YT PTE) isolated from Pseudomonas dimunita has been reported to have high proficiency in hydrolyzing the Sp and Rp-enantiomers of organophosphate chromophoric analogs and therefore has great potential as a decontamination agent and biosensor. This work aims to investigate the feasibility of using Fuller’s earth (FE) as a YT PTE immobilization support and characterize its biochemical features after immobilization. The immobilized YT PTE was found to show improvement in thermal stability with a half-life of 24 h compared to that of the free enzyme, which was only 8 h. The stability of the immobilized YT PTE allowed storage for up to 4 months and reuse for up to 6 times. The immobilized YT PTE showed high tolerance against all tested metal ions, Tween 40 and 80 surfactants and inorganic solvents. These findings showed that the immobilized YT PTE became more robust for use especially with regards to its stability and reusability. These features would enhance the future applicability of this enzyme as a decontamination agent and its use in other suitable industrial applications.

Sodium-based batteries have emerged as promising alternatives to Li-based batteries for future safe, high energy-density energy storage. They are expected to be cheaper, due to the greater abundance of Na and likely reduction in raw material costs. In this study, we investigate the properties of superconcentrated sodium bis(fluorosulfonyl)amide (NaFSI) mixtures with the ionic liquid (IL) methylpropylpyrrolinium (C 3 mpyr) FSI in the presence of ethylene carbonate (EC) in the liquid and gel states. Ionic conductivity and thermal stability are evaluated through electrochemical impedance spectroscopy (EIS) and differential scanning calorimetry (DSC), respectively. NaFSI is soluble in the IL up to 55 mol% Na; adding EC (30 wt.%) to the IL almost doubles the ionic conductivity at ambient temperature. The temperature dependence of conductivity is well described by the Vogel-Tamman-Fulcher equation. NMR spectroscopy and Pulse Field Gradient NMR diffusion were employed to investigate transport in these electrolyte systems, while the chemical interactions were also studied using ATR-FTIR. Stable plasticized gel electrolytes were observed, even at 30 wt. % EC; the formation of the gel does not significantly affect the liquid-like ion dynamics in these materials, as shown by DSC and FTIR analysis. The Na + transference number of Na 0 . 55 [C 3 mpyr] 0.45 [FSI] + 30 wt.% EC was up to 0.32, and deposition and dissolution of sodium metal were observed in cyclic voltammetry around 0 V vs. Na/Na + . Moreover, the suitability of the prepared electrolyte is preliminarily verified in half-cells at room temperature using Na 3 V 2 (PO 4 ) 3 as a cathode. The cells delivered capacity of 52.4 mAhg −1 at C/20.

This review (with 99 refs.) summarizes the progress that has been made in colorimetric (i.e. spectrophotometric) determination of organophosphate pesticides (OPPs) using gold and silver nanoparticles (NPs). Following an introduction into the field, a first large section covers the types and functions of organophosphate pesticides. Methods for colorimetric (spectrophotometric) measurements including RGB techniques are discussed next. A further section covers the characteristic features of gold and silver-based NPs. Syntheses and modifications of metal NPs are covered in section 5. This is followed by overviews on enzyme inhibition-based assays, aptamer-based assays and chemical (non-enzymatic) assays, and a discussion of specific features of colorimetric assays. Several Tables are presented that give an overview on the wealth of methods and materials. A concluding section addresses current challenges and discusses potential future trends and opportunities. Graphical abstractSchematic representation of organophosphate pesticide determinations based on aggregation of nanoparticles (particular silver or gold nanoparticles). This leads to a color change which can be determined visually and monitored by a red shift in the absorption spectrum.

The preparation and properties of surface modification of silica in [Bmim][BF4] -(PVDF-HFP) ionogel haves been investigated. The surface modification of silica was prepared via co condensation of sol gel method using silane coupling agent, vinyltriethoxysilane (VTES). The silica content was characterized and analyzed in term of chemical interaction and thermal stability. Hydrogen bond networks between BF4- and the hydroxyl group in the silica was suggested as the mechanism of this surface modification effect, which was characterized by FTIR. TGA and DSC analysis shows ionogel is stable up to around 475°C, at which a final one-step degradation occurs and increment of glass transition temperature (Tg). [Bmim][BF4] -PVDF-HFP prepared with 30%TEOS-VTES gives the highest value Tg (-81.86°C).

Ionic liquid gel polymer electrolyte (ILGPE) film consisting of poly(vinylidene fluoride-hexafluoropropylene) (PVdF-HFP) and 1-butyl-3-methylimidazolium tetrafluoroborate [Bmim][BF4] with different composition ratio were prepared through solution casting technique. The prepared films were subjected to impedance, temperature dependence, and total ionic transference number analysis. Ionic conductivity for each ILGPEs were measured at room temperature and with increasing temperature ranging from 303 to 373 K. The maximum room temperature ionic conductivity is found to be 2.84 × 10-3 S cm-1 for film containing 60% composition ratio of [Bmim][BF4]. Temperature dependence analysis showed that the ionic conductivity of the ILGPEs increased with increasing temperature and seem to obey Arrhenius behaviour. Total ionic transference number showed that ions are the major charge carriers in this system.Ionic liquid gel polymer electrolyte (ILGPE) film consisting of poly(vinylidene fluoride-hexafluoropropylene) (PVdF-HFP) and 1-butyl-3-methylimidazolium tetrafluoroborate [Bmim][BF4] with different composition ratio were prepared through solution casting technique. The prepared films were subjected to impedance, temperature dependence, and total ionic transference number analysis. Ionic conductivity for each ILGPEs were measured at room temperature and with increasing temperature ranging from 303 to 373 K. The maximum room temperature ionic conductivity is found to be 2.84 × 10-3 S cm-1 for film containing 60% composition ratio of [Bmim][BF4]. Temperature dependence analysis showed that the ionic conductivity of the ILGPEs increased with increasing temperature and seem to obey Arrhenius behaviour. Total ionic transference number showed that ions are the major charge carriers in this system.

In recent years, cellulose nanofiber (CNF) has become an avidly researched material in cutting edge research fields involving prominent researchers, both in academia and industry. This has become an exciting time reaching beyond just scientific curiosity as CNF is beginning to enter various marketplaces. CNF shows unique and potentially useful features, which includes abundance, high specific surface area, renewability, high strength, eco-friendliness and high crystallinity. It is an excellent material for polymer reinforcement. Many studies have been conducted to understand the effects of CNF as a filler in polymer composites. Interestingly, most CNF polymer composites have shown a better mechanical performance compared to the neat base polymer. Thus, this enhances the application of CNF into reinforced polymer composites in several industries such as automotive, packaging, medical implant, electronics, building material and paper. Therefore, in this review, the performances of CNF polymer composites are carefully evaluated. Beyond that, several factors influencing the performance of these composites are discussed.