Displaying publications 101 - 120 of 10357 in total

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  1. Evaluating the critical strain energy release rate of bioactive glass coatings on Ti6Al4V substrates after degradation
    Matinmanesh A, Li Y, Nouhi A, Zalzal P, Schemitsch EH, Towler MR, et al.
    J Mech Behav Biomed Mater, 2018 02;78:273-281.
    PMID: 29190533 DOI: 10.1016/j.jmbbm.2017.11.015
    It has been reported that the adhesion of bioactive glass coatings to Ti6Al4V reduces after degradation, however, this effect has not been quantified. This paper uses bilayer double cantilever (DCB) specimens to determine GIC and GIIC, the critical mode I and mode II strain energy release rates, respectively, of bioactive coating/Ti6Al4V substrate systems degraded to different extents. Three borate-based bioactive glass coatings with increasing amounts of incorporated SrO (0, 15 and 25mol%) were enamelled onto Ti6Al4V substrates and then immersed in de-ionized water for 2, 6 and 24h. The weight loss of each glass composition was measured and it was found that the dissolution rate significantly decreased with increasing SrO content. The extent of dissolution was consistent with the hypothesis that the compressive residual stress tends to reduce the dissolution rate of bioactive glasses. After drying, the bilayer DCB specimens were created and subjected to nearly mode I and mode II fracture tests. The toughest coating/substrate system (one composed of the glass containing 25mol% SrO) lost 80% and 85% of its GIC and GIIC, respectively, in less than 24h of degradation. The drop in GIC and GIIC occurred even more rapidly for other coating/substrate systems. Therefore, degradation of borate bioactive glass coatings is inversely related to their fracture toughness when coated onto Ti6A4V substrates. Finally, roughening the substrate was found to be inconsequential in increasing the toughness of the system as the fracture toughness was limited by the cohesive toughness of the glass itself.
    Matched MeSH terms: Glass/chemistry*; Titanium/chemistry*
  2. Fulltext Kinetic study of lipase-catalyzed glycerolysis of palm olein using Lipozyme TLIM in solvent-free system
    Choong TSY, Yeoh CM, Phuah ET, Siew WL, Lee YY, Tang TK, et al.
    PLoS One, 2018;13(2):e0192375.
    PMID: 29401481 DOI: 10.1371/journal.pone.0192375
    Diacylglycerol (DAG) and monoacylglycerol (MAG) are two natural occurring minor components found in most edible fats and oils. These compounds have gained increasing market demand owing to their unique physicochemical properties. Enzymatic glycerolysis in solvent-free system might be a promising approach in producing DAG and MAG-enriched oil. Understanding on glycerolysis mechanism is therefore of great importance for process simulation and optimization. In this study, a commercial immobilized lipase (Lipozyme TL IM) was used to catalyze the glycerolysis reaction. The kinetics of enzymatic glycerolysis reaction between triacylglycerol (TAG) and glycerol (G) were modeled using rate equation with unsteady-state assumption. Ternary complex, ping-pong bi-bi and complex ping-pong bi-bi models were proposed and compared in this study. The reaction rate constants were determined using non-linear regression and sum of square errors (SSE) were minimized. Present work revealed satisfactory agreement between experimental data and the result generated by complex ping-pong bi-bi model as compared to other models. The proposed kinetic model would facilitate understanding on enzymatic glycerolysis for DAG and MAG production and design optimization of a pilot-scale reactor.
    Matched MeSH terms: Glycerol/chemistry*; Lipase/chemistry*
  3. Removing methylene blue from water: A study of sorption effectiveness onto nanoparticles-doped activated carbon
    Obayomi KS, Lau SY, Zahir A, Meunier L, Zhang J, Dada AO, et al.
    Chemosphere, 2023 Feb;313:137533.
    PMID: 36528163 DOI: 10.1016/j.chemosphere.2022.137533
    In this present study, silver (Ag) and titanium dioxide (TiO2) nanoparticles were successfully deposited on coconut shell-derived activated carbon (CSAC), to synthesize a novel nanocomposite (CSAC@AgNPs@TiO2NPs) for the adsorption of Methylene Blue (MB) dye from aqueous solution. The fabricated CSAC@AgNPs@TiO2NPs nanocomposite was analyzed by Scanning Electron Microscope (SEM), X-ray Diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FTIR), Transmission Electron Microscope (TEM) equipped with Energy Dispersive X-ray spectroscopy (EDS) detector, X-ray Photoelectron Spectroscope (XPS), and Brunauer-Emmett-Teller (BET). The successful deposition of AgNPs and TiO2NPs on CSAC surface was revealed by the TEM/EDX, SEM, and XPS analysis. The mesopore structure of CSAC@AgNPs@TiO2NPs has a BET surface area of 301 m2/g. The batch adsorption studies were conducted and the influence of different parameters, i.e., adsorbent dose, adsorption time, initial dye concentration, pH and temperature were investigated. The nonlinear isotherm and kinetic modelling demonstrated that adsorption data were best fitted by Sips isotherm and pseudo-second-order models, respectively. The maximum adsorption capacity of MB onto CSAC@AgNPs@TiO2NPs by the Sips model was 184 mg/g. Thermodynamic results revealed that the adsorption was endothermic, spontaneous and physical in nature. CSAC@AgNPs@TiO2NPs revealed that MB absorption by CSAC@AgNPs@TiO2NPs was spontaneous and endothermic. The uptake capacity of MB was influenced significantly by the presence of competing ions including, NO3-, HCO3, Ca2+, and Na+. Repeated tests indicated that the CSAC@AgNPs@TiO2NPs can be regenerated and reused six times before being discarded. The primary separation mechanism between MB dye and CSAC@AgNPs@TiO2NPs was the electrostatic interaction. Thus, CSAC@AgNPs@TiO2NPs was an outstanding material, which displayed good applicability in real water with ≥ 97% removal of MB dye.
    Matched MeSH terms: Charcoal/chemistry; Methylene Blue/chemistry
  4. Electrochemical biosensor based on Temporin-PTA peptide for detection of microorganisms
    da Silva-Junio AG, Frias IAM, Lima-Neto RG, Migliolo L, E Silva PS, Oliveira MDL, et al.
    J Pharm Biomed Anal, 2022 Jul 15;216:114788.
    PMID: 35525110 DOI: 10.1016/j.jpba.2022.114788
    Bacterial and fungal infections are challenging due to their low susceptibility and resistance to antimicrobial drugs. For this reason, antimicrobial peptides (AMP) emerge as excellent alternatives to overcome these problems. At the same time, their active insertion into the cell wall of microorganisms can be availed for biorecognition applications in biosensing platforms. Temporin-PTA (T-PTA) is an AMP found in the skin secretions of the Malaysian fire frog Hylarana picturata, which presents antibacterial activity against MRSA, Escherichia coli, and Bacillus subtilis. In this work, T-PTA was explored as an innovative sensing layer aiming for the electrochemical differentiation of Klebsiella pneumoniae, Acinetobacter baumannii, Bacillus subtilis, Enterococcus faecalis, Candida albicans, and C. tropicalis based on the structural differences of their membranes. The biosensor was analyzed through electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). In this approach, the different structural features of each microorganism resulted in different adherence degrees and, therefore, different electrochemical responses. The transducing layer was fabricated by the self-assembling of a 4-mercaptobenzoic acid (MBA) monolayer and gold-capped magnetic nanoparticles (Fe3O4@Au) implemented to improve the electrical signal of the biointeraction. We found that each interaction, expressed in variations of electron transfer resistance and anodic peak current, demonstrated a singular response from which the platform can discriminate all different microorganisms. We found expressive sensitivity towards Gram-negative species, especially K. pneumoniae. A detection limit of 101 CFU.mL-1 and a linear range of 101 to 105 CFU.mL-1 were obtained. The T-PTA biosensor platform is a promising and effective tool for microbial identification.
    Matched MeSH terms: Gold/chemistry; Antimicrobial Cationic Peptides/chemistry
  5. Challenges and opportunities for biochar to promote circular economy and carbon neutrality
    Kurniawan TA, Othman MHD, Liang X, Goh HH, Gikas P, Chong KK, et al.
    J Environ Manage, 2023 Apr 15;332:117429.
    PMID: 36773474 DOI: 10.1016/j.jenvman.2023.117429
    Biochar, derived from unused biomass, is widely considered for its potential to deal with climate change problems. Global interest in biochar is attributed to its ability to sequester carbon in soil and to remediate aquatic environment from water pollution. As soil conditioner and/or adsorbent, biochar offers opportunity through a circular economy (CE) paradigm. While energy transition continues, progress toward low-emissions materials accelerates their advance towards net-zero emissions. However, none of existing works addresses CE-based biochar management to achieve carbon neutrality. To reflect its novelty, this work provides a critical overview of challenges and opportunities for biochar to promote CE and carbon neutrality. This article also offers seminal perspectives about strengthening biomass management through CE and resource recovery paradigms, while exploring how the unused biomass can promote net zero emissions in its applications. By consolidating scattered knowledge in the body of literature into one place, this work uncovers new research directions to close the loops by implementing the circularity of biomass resources in various fields. It is conclusive from a literature survey of 113 articles (2003-2023) that biomass conversion into biochar can promote net zero emissions and CE in the framework of the UN Sustainable Development Goals (SDGs). Depending on their physico-chemical properties, biochar can become a suitable feedstock for CE. Biochar application as soil enrichment offsets 12% of CO2 emissions by land use annually. Adding biochar to soil can improve its health and agricultural productivity, while minimizing about 1/8 of CO2 emissions. Biochar can also sequester CO2 in the long-term and prevent the release of carbon back into the atmosphere after its decomposition. This practice could sequester 2.5 gigatons (Gt) of CO2 annually. With the global biochar market reaching USD 368.85 million by 2028, this work facilitates biochar with its versatile characteristics to promote carbon neutrality and CE applications.
    Matched MeSH terms: Charcoal/chemistry; Soil/chemistry
  6. Fulltext Physicochemical and antioxidative properties of ultrasound-assisted extraction of mahua (Madhuca longifolia) seed oil in comparison with conventional Soxhlet and mechanical extractions
    Thilakarathna RCN, Siow LF, Tang TK, Chan ES, Lee YY
    Ultrason Sonochem, 2023 Jan;92:106280.
    PMID: 36587443 DOI: 10.1016/j.ultsonch.2022.106280
    Ultrasound-assisted solvent extraction (UAE) was applied to extract underutilized Madhuca longifolia seed oil. The effect of extraction time, temperature, solvent type, solvent/sample ratio, and amplitude on the oil yield and recovery were investigated. Approximately 56.97% of oil yield and 99.54% of oil recovery were attained using mild conditions of 35 min, 35 °C, 40% amplitude, isopropanol to acetone (1:1), and solvent to sample (20 mL/g). UAE oil yield and recovery were comparable with Soxhlet extraction (SXE) whilst mechanical pressing (ME) yielded 
    Matched MeSH terms: Plant Oils/chemistry; Solvents/chemistry
  7. Role of silica-based porous cellulose nanocrystals in improving water absorption and mechanical properties
    Aziz T, Farid A, Haq F, Kiran M, Ullah N, Faisal S, et al.
    Environ Res, 2023 Apr 01;222:115253.
    PMID: 36702191 DOI: 10.1016/j.envres.2023.115253
    Epoxy resins are important thermosetting polymers. They are widely used in many applications i.e., adhesives, plastics, coatings and sealers. Epoxy molding compounds have attained dominance among common materials due to their excellent mechanical properties. The sol-gel simple method was applied to distinguish the impact on the colloidal time. The properties were obtained with silica-based fillers to enable their mechanical and thermal improvement. The work which we have done here on epoxy-based nanocomposites was successfully modified. The purpose of this research was to look into the effects of cellulose nanocrystals (CNCs) on various properties and applications. CNCs have recently attracted a lot of interest in a variety of industries due to their high aspect ratio, and low density which makes them perfect candidates. Adding different amounts of silica-based nanocomposites to the epoxy system. Analyzed with different techniques such as Fourier-transformed infrared spectroscope (FTIR), thermogravimetric analysis (TGA) and scanning electronic microscopic (SEM) to investigate the morphological properties of modified composites. The various %-age of silica composite was prepared in the epoxy system. The 20% of silica was shown greater enhancement and improvement. They show a better result than D-400 epoxy. Increasing the silica, the transparency of the films decreased, because clustering appears. This shows that the broad use of CNCs in environmental engineering applications is possible, particularly for surface modification, which was evaluated for qualities such as absorption and chemical resistant behavior.
    Matched MeSH terms: Silicon Dioxide/chemistry; Water/chemistry
  8. Fulltext Ecofriendly adsorption and sensitive detection of Hg (II) by biomass-derived nitrogen-doped carbon dots: process modelling using central composite design
    Issa MA, Zentou H, Jabbar ZH, Abidin ZZ, Harun H, Halim NAA, et al.
    Environ Sci Pollut Res Int, 2022 Dec;29(57):86859-86872.
    PMID: 35802332 DOI: 10.1007/s11356-022-21844-0
    In this study, luminescent bio-adsorbent nitrogen-doped carbon dots (N-CDs) was produced and applied for the removal and detection of Hg (II) from aqueous media. N-CDs were synthesized from oil palm empty fruit bunch carboxymethylcellulose (CMC) and urea. According to several analytical techniques used, the obtained N-CDs display graphitic core with an average size of 4.2 nm, are enriched with active sites, stable over a wide range of pH and have great resistance to photobleaching. The N-CDs have bright blue emission with an improved quantum yield (QY) of up to 35.5%. The effect of the variables including pH, adsorbent mass, initial concentration and incubation time on the removal of Hg (II) was investigated using central composite design. The statistical results confirmed that the adsorption process could reach equilibrium within 30 min. The reduced cubic model (R2 = 0.9989) revealed a good correlation between the observed values and predicted data. The optimal variables were pH of 7, dose of 0.1 g, initial concentration of 100 mg/L and duration of 30 min. Under these conditions, adsorption efficiency of 84.6% was obtained. The adsorption kinetic data could be well expressed by pseudo-second-order kinetic and Langmuir isotherm models. The optimal adsorption capacity was 116.3 mg g-1. Furthermore, the adsorbent has a good selectivity towards Hg (II) with a detection limit of 0.01 μM due to the special interaction between Hg (II) and carboxyl/amino groups on the edge of N-CDs. This work provided an alternative direction for constructing low-cost adsorbents with effective sorption and sensing of Hg (II).
    Matched MeSH terms: Carbon/chemistry; Nitrogen/chemistry
  9. Fulltext Extraction of non-starch lipid from protease-treated wheat flour
    Abdul Manan SF, Li J, Hsieh CF, Faubion J, Shi YC
    J Sci Food Agric, 2022 Mar 30;102(5):2172-2178.
    PMID: 34498279 DOI: 10.1002/jsfa.11523
    BACKGROUND: Lipids account for 2.0-2.5% of wheat flour by dry weight and affect properties and quality of cereal foods. A new method was developed to extract non-starch lipids from wheat flour. Wheat flour was first hydrolyzed with a protease and followed by extraction of non-starch lipids by water-saturated butanol (WSB).

    RESULT: Protein hydrolysis by protease followed by extraction of non-starch lipids with WSB increased yield to 1.9 ± 0.3% from 1.0 ± 0.1% with no protease treatment. The lipid profile showed a significant increase in phospholipid compounds extracted with protease hydrolysis (5.9 ± 0.8 nmol·g-1 ) versus without enzymatic treatment (2.4 ± 1.3 nmol g-1 ).

    CONCLUSION: Improved lipid extraction yield and phospholipid compounds following protease-assisted extraction method provided additional insight towards the understanding of protein-lipid interaction in wheat flour. The new protease-assisted extraction method may be applied to analyzing non-starch lipids in other types of wheat flours and other cereal flours. © 2021 Society of Chemical Industry.

    Matched MeSH terms: Lipids/chemistry; Starch/chemistry
  10. Fulltext Hydrogen gas sensing performance of a carbon-doped boron nitride nanoribbon at elevated temperatures
    Taib AK, Johari Z, Abd Rahman SF, Mohd Yusoff MF, Hamzah A
    PLoS One, 2023;18(3):e0282370.
    PMID: 36897883 DOI: 10.1371/journal.pone.0282370
    In this study, computational simulations were used to investigate the performance of a carbon-doped boron nitride nanoribbon (BC2NNR) for hydrogen (H2) gas sensing at elevated temperatures. The adsorption energy and charge transfer were calculated when H2 was simultaneously attached to carbon, boron, and both boron and nitrogen atoms. The sensing ability was further analyzed considering the variations in current-voltage (I-V) characteristics. The simulation results indicated that the energy bandgap of H2 on carbon, boron, and both boron and nitrogen exhibited a marginal effect during temperature variations. However, significant differences were observed in terms of adsorption energy at a temperature of 500 K, wherein the adsorption energy was increased by 99.62% of that observed at 298 K. Additionally, the evaluation of charge transfer indicated that the strongest binding site was achieved at high adsorption energies with high charge transfers. Analysis of the I-V characteristics verified that the currents were considerably affected, particularly when a certain concentration of H2 molecules was added at the highest sensitivity of 15.02% with a bias voltage of 3 V. The sensitivity at 298 K was lower than those observed at 500 and 1000 K. The study findings can form the basis for further experimental investigations on BC2NNR as a hydrogen sensor.
    Matched MeSH terms: Boron/chemistry; Hydrogen/chemistry
  11. Fulltext Stable and Efficient Dye-Sensitized Solar Cells and Supercapacitors Developed Using Ionic-Liquid-Doped Biopolymer Electrolytes
    Konwar S, Singh D, Strzałkowski K, Masri MNB, Yahya MZA, Diantoro M, et al.
    Molecules, 2023 Jun 29;28(13).
    PMID: 37446761 DOI: 10.3390/molecules28135099
    An ionic liquid (IL) 1-ethyl, 2-methyl imidazolium thiocyanate incorporated biopolymer system is reported in this communication for applications in dual energy devices, i.e., electric double-layer capacitors (EDLCs) and dye-sensitized solar cells (DSSCs). The solution caste method has been used to synthesize ionic-liquid-incorporated biopolymer electrolyte films. The IL mixed biopolymer electrolytes achieve high ionic conductivity up to the order of 10-3 S/cm with good thermal stability above 250 °C. Electrical, structural, and optical studies of these IL-doped biopolymer electrolyte films are presented in detail. The performance of EDLCs was evaluated using low-frequency electrochemical impedance spectroscopy, cyclic voltammetry, and constant current charge-discharge, while that of DSSCs was assessed using J-V characteristics. The EDLC cells exhibited a high specific capacitance of 200 F/gram, while DSSCs delivered 1.53% efficiency under sun conditions.
    Matched MeSH terms: Coloring Agents/chemistry; Electrolytes/chemistry
  12. Physicochemical and thermal characteristics of choline chloride-based deep eutectic solvents
    Sazali AL, AlMasoud N, Amran SK, Alomar TS, Pa'ee KF, El-Bahy ZM, et al.
    Chemosphere, 2023 Oct;338:139485.
    PMID: 37442394 DOI: 10.1016/j.chemosphere.2023.139485
    It is essential to investigate the physicochemical and thermal properties of choline chloride (ChCl)-based deep eutectic solvents (DESs) as hydrogen bond acceptor (HBA) with various hydrogen bond donor (HBD) functional groups, such as α-hydroxy acid (lactic acid) or polyol (glycerol). It is important to consider how molar ratios impact these properties, as they may be altered for particular applications. This study aimed to examine the physicochemical and thermal properties of ChCl-based DESs with lactic acid (LA) or glycerol (Gly) at different molar ratios (1:2-1:10). The pH of ChCl:LA (0-1.0) is lower than that of ChCl:Gly (4.0-5.0) because of the hydrogen bonds between ChCl and LA. A higher amount of LA/Gly resulted in higher densities of ChCl:Gly (1.20-1.22 g cm-3) and ChCl:LA (1.16-1.19 g cm-3) due to the stronger hydrogen bonds and tighter packing of the molecules. The refractive index of ChCl:Gly (1.47-1.48) was higher than ChCl:LA (1.44-1.46), with a trend similar to density. The viscosities of ChCl:Gly (0.235-0.453 Pa s) and ChCl:LA (0.04-0.06 Pa s) increased with increasing LA/Gly molar ratio but decreased with temperature due to the high kinetic energy from heating, lowering the attractive forces between molecules. The activation energy for ChCl:LA (15.29-15.55 kJ mol-1) is greater than for ChCl:Gly (7.77-8.78 kJ mol-1), indicating that ChCl:LA has a greater viscosity-temperature dependence than ChCl:Gly. The DESs decomposition temperatures are 179.73-192.14 °C for ChCl:LA and 189.69-197.41 °C for ChCl:Gly. Freezing temperatures are correlated with the molecular weight of HBDs, with lower values causing a larger decrease in freezing temperatures. The interactions of polyols with anions were stronger than those of α-hydroxy acids with anions. The variations in HBA to HBD molar ratios affected DESs properties, providing a fundamental understanding of the properties critical for their diverse applications.
    Matched MeSH terms: Choline/chemistry; Solvents/chemistry
  13. Oil palm frond-derived cellulose nanocrystals: Effect of pretreatment and elucidating its reinforcing potential in hydrogel beads
    Hamidon TS, Idris NN, Adnan R, Haafiz MKM, Zahari A, Hussin MH
    Int J Biol Macromol, 2024 Mar;262(Pt 2):130239.
    PMID: 38367788 DOI: 10.1016/j.ijbiomac.2024.130239
    Herein, cellulose nanocrystals were synthesized from oil palm fronds (CNC-OPF) involving two pretreatment approaches, viz. autohydrolysis and soda pulping. The pretreatments were applied individually to OPF fibers to assess their influence on CNCs' physicochemical and thermal properties. CNC-OPF samples were assessed using complementary characterization techniques, which confirmed their purity and characteristics. CP/MAS 13C NMR and TEM studies revealed that autohydrolysis pretreatment yielded CNCs with effective hemicellulose and extractives removal compared to that of soda pulping. XRD analysis demonstrated that autohydrolysis-treated CNC-OPF contained a much higher crystallinity index compared to soda pulping treatment. BET measurement disclosed a relatively higher surface area and wider pore diameter of autohydrolysis-treated CNC-OPF. Autohydrolysis-treated CNCs were applied as a reinforcement filler in alginate-based hydrogel beads for the removal of 4-chlorophenol from water, which attained a qmax of 19.168 mg g-1. BET analysis revealed the less porous nature of CNC-ALG hydrogel beads which could have contributed to hydrogel beads' relatively lower adsorption capacity. The point of zero charge of CNC-ALG hydrogel beads was 4.82, suggesting their applicability only within a short solution pH range. This study directs future studies to unveil the possibilities of functionalizing CNCs in order to enhance the adsorption performance of CNC-immobilized hydrogel beads towards 4-chlorophenol and other organic contaminants.
    Matched MeSH terms: Cellulose/chemistry; Hydrogels/chemistry
  14. Fulltext Tetrabutylammonium bromide (TBABr)-based deep eutectic solvents (DESs) and their physical properties
    Yusof R, Abdulmalek E, Sirat K, Rahman MB
    Molecules, 2014 Jun 13;19(6):8011-26.
    PMID: 24932572 DOI: 10.3390/molecules19068011
    Density, viscosity and ionic conductivity data sets of deep eutectic solvents (DESs) formed by tetrabutylammonium bromide (TBABr) paired with ethlyene glycol, 1,3-propanediol, 1,5-pentanediol and glycerol hydrogen bond donors (HBDs) are reported. The properties of DES were measured at temperatures between 303 K and 333 K for HBD percentages of 66.7% to 90%. The effects of HBDs under different temperature and percentages are systematically analyzed. As expected, the measured density and viscosity of the studied DESs decreased with an increase in temperature, while ionic conductivity increases with temperature. In general, DESs made of TBABr and glycerol showed the highest density and viscosity and the lowest ionic conductivity when compared to other DESs. The presence of an extra hydroxyl group on glycerol in a DES affected the properties of the DES.
    Matched MeSH terms: Quaternary Ammonium Compounds/chemistry*; Solvents/chemistry*
  15. Chitosan as a suitable host for sustainable plasticized nanocomposite sodium ion conducting polymer electrolyte in EDLC applications: Structural, ion transport and electrochemical studies
    Sadiq NM, Abdulwahid RT, Aziz SB, Woo HJ, Kadir MFZ
    Int J Biol Macromol, 2024 Apr;265(Pt 1):130751.
    PMID: 38471616 DOI: 10.1016/j.ijbiomac.2024.130751
    The challenge in front of EDLC device is their low energy density compared to their battery counter parts. In the current study, a green plasticized nanocomposite sodium ion conducting polymer blend electrolytes (PNSPBE) was developed by incorporating plasticized Chitosan (CS) blended with polyvinyl alcohol (PVA), doped with NaBr salt with various concentration of CaTiO3 nanoparticles. The most optimized PNSPBE film was subsequently utilized in an EDLC device to evaluate its effectiveness both as an electrolyte and a separator. Structural and morphological changes were assessed using XRD and SEM techniques. The PNSPBE film demonstrated a peak ionic conductivity of 9.76×10-5 S/cm, as determined through EIS analysis. The dielectric and AC studies provided further confirmation of structural modifications within the sample. Both TNM and LSV analyses affirmed the suitability of the prepared electrolyte for energy device applications, evidenced by its adequate ion transference number and an electrochemical potential window of 2.86 V. Electrochemical properties were assessed via CV and GCD techniques, confirming non-Faradaic ion storage, indicated by the rectangular CV pattern at low scan rates. The parameters associated with the designed EDLC device including specific capacitance, ESR, power density (1950 W/kg) and energy density (12.3 Wh/kg) were determined over 1000 cycles.
    Matched MeSH terms: Electrolytes/chemistry; Ions/chemistry
  16. Fulltext Internal Factors Affecting the Crystallization of the Lipid System: Triacylglycerol Structure, Composition, and Minor Components
    Yang D, Lee YY, Lu Y, Wang Y, Zhang Z
    Molecules, 2024 Apr 18;29(8).
    PMID: 38675667 DOI: 10.3390/molecules29081847
    The process of lipid crystallization influences the characteristics of lipid. By changing the chemical composition of the lipid system, the crystallization behavior could be controlled. This review elucidates the internal factors affecting lipid crystallization, including triacylglycerol (TAG) structure, TAG composition, and minor components. The influence of these factors on the TAG crystal polymorphic form, nanostructure, microstructure, and physical properties is discussed. The interplay of these factors collectively influences crystallization across various scales. Variations in fatty acid chain length, double bonds, and branching, along with their arrangement on the glycerol backbone, dictate molecular interactions within and between TAG molecules. High-melting-point TAG dominates crystallization, while liquid oil hinders the process but facilitates polymorphic transitions. Unique molecular interactions arise from specific TAG combinations, yielding molecular compounds with distinctive properties. Nanoscale crystallization is significantly impacted by liquid oil and minor components. The interaction between the TAG and minor components determines the influence of minor components on the crystallization process. In addition, future perspectives on better design and control of lipid crystallization are also presented.
    Matched MeSH terms: Fatty Acids/chemistry; Lipids/chemistry
  17. Novel enhancement of interfacial interaction and properties in biodegradable polymer composites using green chemically treated spent coffee ground microfiller
    Majrashi MAA, Bairwan RD, Mushtaq RY, Khalil HPSA, Badr MY, Alissa M, et al.
    Int J Biol Macromol, 2024 May;266(Pt 2):131333.
    PMID: 38574916 DOI: 10.1016/j.ijbiomac.2024.131333
    This study investigates the potential of utilizing green chemically treated spent coffee grounds (SCGs) as micro biofiller reinforcement in Poly-3-hydroxybutyrate-co-3-hydroxyvalerate (PHBV) biopolymer composites. The aim is to assess the impact of varying SCG concentrations (1 %, 3 %, 5 %, and 7 %) on the functional, thermal, mechanical properties and biodegradability of the resulting composites with a PHBV matrix. The samples were produced through melt compounding using a twin-screw extruder and compression molding. The findings indicate successful dispersion and distribution of SCGs microfiller into PHBV. Chemical treatment of SCG microfiller enhanced the interfacial bonding between the SCG and PHBV, evidenced by higher water contact angles of the biopolymer composites. Field Emission Scanning Electron Microscopy (FE-SEM) confirmed the successful interaction of treated SCG microfiller, contributing to enhanced mechanical characteristics. A two-way ANOVA was conducted for statistical analysis. Mass losses observed after burying the materials in natural soil indicated that the composites degraded faster than the pure PHBV polymer suggesting that both composites are biodegradable, particularly at high levels of spent coffee grounds (SCG). Despite the possibility of agglomeration at higher concentrations, SCG incorporation resulted in improved functional properties, positioning the green biopolymer composite as a promising material for sustainable packaging and diverse applications.
    Matched MeSH terms: Green Chemistry Technology; Biodegradable Plastics/chemistry
  18. Asterias Rolleston starfish gonad lipids: A novel source of Omega-3 fatty acids - assessment of major components and their antioxidant activities
    Xie P, Wu Y, Lee YY, Wang Y, Zhang Z
    Food Chem, 2024 Oct 30;456:140005.
    PMID: 38870815 DOI: 10.1016/j.foodchem.2024.140005
    The major lipids and antioxidant activities of Asterias rolleston gonad lipids were evaluated systematically. Major lipids of A. Rolleston gonad lipids were triacylglycerols (TAGs) and phospholipids (PLs). Total lipids were composed of 15.62% of polyunsaturated fatty acids (PUFAs), and 40.81% of monounsaturated fatty acids (MUFAs). The most abundant PUFA were C20:5n-3 (EPA) (6.28%) and C22:6n-3 (DHA) (5.80%). Predominantly composed of phosphatidylcholine (PC) and phosphatidylethanolamine (PE), polar lipids were rich in PUFAs and could contain up to 34.59% EPA and DHA, and PE and PI (phosphatidylinositol) were also found to be the main carriers of EPA and ARA (arachidonic acid) in polar lipids. The MUFA and PUFA of Sn-2 in TAG are 39.72% and 30.37%, respectively. A total of 64 TAG species were identified, with Eo-P-M, Eo-Eo-M, and M-M-Eo being the main TAGs components. Moreover, A. rollestoni gonad lipids exhibited potent radical scavenging activities and reducing power in a dose-dependent manner.
    Matched MeSH terms: Lipids/chemistry; Phospholipids/chemistry
  19. Fulltext Pickering emulsion stabilized by palm-pressed fiber cellulose nanocrystal extracted by acid hydrolysis-assisted high pressure homogenization
    Ng SW, Chong WT, Soo YT, Tang TK, Ab Karim NA, Phuah ET, et al.
    PLoS One, 2022;17(8):e0271512.
    PMID: 36044467 DOI: 10.1371/journal.pone.0271512
    Palm pressed fibre (PPF) is a lignocellulose biomass generated from palm oil mill that is rich in cellulose. The present work aimed to combine acid hydrolysis followed by high-pressure homogenisation (HPH) to produce nanocrystal cellulose (CNC) with enhanced physicochemical properties from PPF. PPF was alkaline treated, bleached, acid hydrolysed and homogenised under high pressure condition to prepare CNC. The effects of homogenisation pressure (10, 30, 50, 70 MPa) and cycles (1, 3, 5, 7) on the particle size, zeta potential and rheological properties of CNC produced were investigated. HPH was capable of producing CNC with better stability. Results revealed that utilizing 1 cycle of homogenisation at a pressure of 50 MPa resulted in CNC with the smallest dimension, highest aspect ratio, moderate viscosity and exceptionally high zeta potential. Subsequently, 0.15% (CNC 0.15 -PE) and 0.30% (CNC 0.30 -PE) of CNC was used to stabilise oil-in-water emulsions and their stability was evaluated against different pH, temperature and ionic strength. All the CNC-stabilised emulsions demonstrated good thermal stability. CNC 0.30 -PE exhibited larger droplets but higher stability than CNC 0.15 -PE. In short, CNC with gel like structure has a promising potential to serve as a natural Pickering emulsifier to stabilise oil-in-water emulsion in various food applications.
    Matched MeSH terms: Emulsions/chemistry; Water/chemistry
  20. New Y-shaped surfactants from renewable resources
    Ali TH, Hussen RS, Heidelberg T
    Colloids Surf B Biointerfaces, 2014 Nov 1;123:981-5.
    PMID: 25465761 DOI: 10.1016/j.colsurfb.2014.10.054
    A series of sugar-based surfactants, involving a single hydrophobic chain (C12) and two side-by-side arranged head groups, was prepared form simple glucose precursors. All surfactants were highly water soluble and exhibited exclusively micellar assemblies. This behavior makes them interesting candidates for oil in water emulsifiers.
    Matched MeSH terms: Emulsions/chemistry*; Surface-Active Agents/chemistry*; Click Chemistry/methods*
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