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•Unorthodox synthesis of reusable collagen-g-terpolymer-g-guar gum superadsorbent.•In situ protrusion of acrylamido propanoic acid monomer in terpolymer network.•Advanced ...adsorbed/unadsorbed microstructural analyses for superadsorption mechanism.•1H-/13C-NMR, XPS, FTIR, UV–vis, TGA-DSC, XRD, and isotherms-kinetics-thermodynamics.•Removals of p-nitrophenol, vitamin C/ascorbic acid, Hg(II)/Pb(II), and MB/MV.
Herein, guar gum (GG)-g-(acrylic acid (AA)-co-3-acrylamido propanoic acid (AMPA)-co-acrylamide (AM))-g-cow buffing dust (CBD)/(GGTPCBD), a smart carbohydrate and protein-based doubly-grafted interpenetrating terpolymer hydrogel showing excellent physicochemical properties and recyclability was synthesized by in situ strategic allocation of AMPA during solution polymerization of AA and AM through systematic optimization of the amounts of components and reaction temperature for superadsorption of Hg(II), Pb(II), methyl violet (MV), methylene blue (MB), p-nitrophenol (PNP), and vitamin-C (vit.C). The in situ strategic protrusion of AMPA, grafting of both GG and CBD into AA-co-AMPA-co-AM, and ligand-selective superadsorption was inferred by advanced microstructural analyses of unadsorbed- and/or adsorbed-GGTPCBD using FTIR, 1H/13C NMR, O1s-/N1s-/C1s-/Pb4f7/2,5/2-/Hg4f7/2,5/2-XPS, UV–vis, TGA, DSC, XRD, DLS, SEM, EDX, % gel content, % −COOH, and pHPZC. The prevalence of covalent, ionic, and variegated interactions was rationalized by FTIR, fitting of kinetics data to the pseudosecond order model, and activation energies of adsorption. The BET and Langmuir isotherms fitted the best to MB and Hg(II)/Pb(II)/MV, respectively. Thermodynamically spontaneous chemisorption processes showed the maximum adsorption capacities (ACs) of 976.64, 859.23, 116.80, and 58.52 mg g−1 for Pb(II), Hg(II), MV, and MB, respectively, at 303 K, adsorbent dose = 0.01 g, and initial concentration of metal ions/dyes = 800/30 ppm.
Despite many advantages, the practical application of fullerene C60 and curcumin (CUR) has been limited by their hydrophobic nature, deficient solubility in aqueous media and, therefore, poor ...bioavailability. In this study, aqueous nanoformulations containing C60 and CUR in the absence and presence of three solubility enhancers, β-cyclodextrin (CD), Tween 80 (T80) and polyvinylpyrrolidone (PVP), were prepared and subjected to the antioxidant activity assessment. The content of C60 and CUR, stability, size and morphology of nanoparticles were determined using UV–vis, DLS and SEM techniques. Contrary to better solubility of pure C60 than the corresponding C60-CUR system, the solubilization of CUR in hybrid suspensions was improved compared to corresponding pure CUR suspensions, with the exception of the C60-CUR-PVP formulation. The DLS results revealed nearly monodisperse nature of CUR-T80 nanoformulation, while other ones ranged from widely dispersed to polydispersed. Depending on the type of solubilizer, similarity was observed in the particle size distributions of T80- and PVP-coated nanoformulations as well as water and CD nanoformulations. The presence of T80 differently and significantly reduces the particle size in all three nanoformulations, while PVP slightly reduces CUR-based nanoparticles but increases the size of C60 nanoparticles. Zeta potential values, ranging from − 9 mV to − 34 mV, show variation in the starting stability of nanoparticles, from unstable or relatively stable three PVP formulations and C60-T80 to highly stable CUR-T80 and C60-water. Compared to water nanoformulations as a control, SEM images of dispersant-coated nanoparticles lost the visible morphology of active components, showing variation in their morphology depending on the type of dispersant and active component used. Nanoformulations containing CUR in PVP and T80 expressed a very good antioxidant potential in DPPH radical scavenging assay, much stronger than ascorbic acid. At the same time, a moderate to high antioxidant activity in β-carotene bleaching assay was reached in PVP and T80 nanoformulations containing C60, CUR, and their noncovalent hybrid, as well. Our studies have shown that T80 and PVP colloidal systems containing C60-CUR hybrid, but also their individual components, can be used as stable antioxidant nanoformulations with potential application in the field of food and pharmacology.
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•Pure and combined aqueous dispersions of fullerene C60 and curcumin were prepared.•Addition of Tween 80 and PVP enhanced solubility, contrary to β-cyclodextrin.•DLS revealed moderately to widely dispersed systems; T80 reduces the particle size.•SEM showed the dependence of morphology on dispersant and active component.•Colloidal systems containing curcumin in Tween 80 or PVP act as strong antioxidants.
In these times of efforts to develop high-efficiency hydrogen-adopted or hydrogen-fueled internal combustion engines (ICEs), and concerns related to electric vehicles such as battery cost, drawbacks ...in harsh winter climates, low range, etc., it is important to generate original ideas in line with the manufacturing of ICEs with improved efficacy. Accordingly, this study presents a comprehensive experimental investigation to observe the cooperated effects of pulse width modulation (PWM)-controlled hydroxy (HHO) gas introduction and improvement in tribological performance of piston ring-cylinder liner mechanism on performance and emission characteristics of a spark-ignition (SI) engine (co-system). The variation of compression ratio (CR), influence of two electrolyzer types of tube electrolyzer (TE) and plate electrolyzer (PE) for production of HHO gas, and zeta potential (ZP)-based dynamic light scattering (DLS) analysis to specify the optimal catalyst concentration in de-ionized water were also observed. Electron cyclotron resonance-chemical vapor deposition (ECR-CVD) method was utilized to bombard the piston ring substrates with diamond-like carbon (DLC) atoms under high energy plasma to improve the mechanical strength of the friction surface. Using linear tribometer, the uncoated (UPR) and coated piston rings (CPR) underwent friction tests to determine the wear rate (WR), and coefficient of friction (COF) which have substantial contribution to frictional losses. The surfaces of the samples were visualized via scanning electron microscopy (SEM) and atomic force microscopy (AFM) before and after abrasion tests to analyze carbon coating and its effects on tribological performance. The observations depicted that HHO flowrate needs to be varied as the engine load and CR change, and based on these observations, PWM control unit was designed, manufactured and reprogrammed so as to adjust electrical power consumption of HHO system when needed. The aforementioned analyses ensured optimization of the overall system so as to maximize the efficiency of the test engine. The co-system with optimized parameters (CPR + HHO + PWM) yielded an increase in average brake power (Pe) up to 31%, and average reductions in specific fuel consumption (β), carbon monoxide (CO), unburned hydrocarbon (UHC), and nitrogen oxide (NOx) emissions by 17%, 25%, 19%, and 14%, respectively at engine load range from 20% to 100%. It is expected that this study will be a good guide in terms of developing high-efficient ICEs due to promising results provided by the co-system.
•Electrolyzers.•KOH catalyst.•HHO flow control.•Variable compression ratio.•Tribology.
The nanoscale size of plastic debris makes them potential efficient vectors of many pollutants and more especially of metals. In order to evaluate this ability, nanoplastics were produced from ...microplastics collected on a beach exposed to the North Atlantic Gyre. The nanoplastics were characterized using multi-dimensional methods: asymmetrical flow field flow fractionation and dynamic light scattering coupled to several detectors. Lead (II) adsorption kinetics, isotherm and pH-edge were then carried out. The sorption reached a steady state after around 200 min. The maximum sorption capacity varied between 97% and 78.5% for both tested Pb concentrations. Lead (II) adsorption kinetics is controlled by chemical reactions with the nanoplastics surface and to a lesser extent by intraparticle diffusion. Adsorption isotherm modeling using Freundlich model demonstrated that NPG are strong adsorbents equivalent to hydrous ferric oxides such as ferrihydrite (log Kadsfreundlich=8.36 against 11.76 for NPG and ferrihydrite, respectively). The adsorption is dependent upon pH, in response to the Pb(II) adsorption by the oxygenated binding sites developed on account of the surface UV oxidation under environmental conditions. They could be able to compete with Fe or humic colloids for Pb binding regards to their amount and specific areas. Nanoplastics could therefore be efficient vectors of Pb and probably of many other metals as well in the environment.
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•Pb(II) binding experiments onto nanoplastics extracted from environmental micro-plastics were performed.•Pb(II) was largely bound onto nanoplastics by specific adsorption and intraparticle diffusion.•Nanoplastics could be significant vectors of metals in the environment.
The study sought to ascertain spider mite prevalence, infestation, and identification and to assess the response of potato genotypes. In 2022, this pest was only observed on some genotypes in ...December. In late January, an infestation, incidence, and severity increased from 10 to 13 genotypes on potato tuber stocks stored for irrigation experiments. Those genotypes were planted in irrigated fields, and the sprouted tuber losses ranged from 12.5% to 100% and up to 15.38% in the 2022 and 2023 records, respectively. Following this, spider mites, often known as two-spotted spider mites (TSSM) or Tetranychus urticae, were identified. This is the first time a potato sprout infestation has been recorded in Ethiopia. The two-spotted spider mites damaged the tubers quantitatively by sucking the moisture of sprouts up to the 5th grade, with 97 and >75% infestation levels, incidence, and severity, respectively. The pest grows very rapidly and hastens the drying of sprouted tuber leaves. Some genotypes were resistant to TSSM and recovered after the sprouts were infected and dried, which were treated with pesticides in 2023. The typical agricultural insecticides were ineffective in controlling the pest in the first year, and a Profenofos was applied in the second year. Thus, seed tubers are the main production limit unless appropriate research efforts are undertaken and management techniques are created.
Int. J. Agril. Res. Innov. Tech. 13(2): 55-63, Dec 2023
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Dynamic Light Scattering (DLS) generated particle size distributions (PSD) of polymer-stabilized nanoparticles are dependent on the optimization parameters used to generate an ...inversion solution fit to the measured autocorrelation function. The accuracy of the DLS PSD average and polydispersity can be determined by comparing analyzed Transmission Electron Microscopy (TEM) images with the DLS results if the TEM measured sizes can be corrected for the thickness of the hydrated polymer corona that impacts particle hydrodynamics but is a collapsed, desiccated shell in the TEM images.
Nanoparticles were prepared by Flash NanoPrecipitation with either poly(ethylene glycol) (PEG) or hydroxypropyl methylcellulose acetate succinate (HPMCAS) stabilizing polymers. Solvated nanoparticle size distributions were measured by DLS in aqueous media. The same nanoparticle dispersions were lyophilized onto TEM grids and stained by ruthenium tetroxide (RuO4) vapor to improve electron contrast. Desiccated particle size distributions were generated by measuring a minimum of 300 particle diameters in the stained TEM images.
Using our protocol for staining soft matter nanoparticles in TEM measurements, we have quantitatively analyzed the correlation between DLS and TEM generated PSDs. Average diameters disagree by the hydrated polymer corona thickness for each stabilizer due to the high-vacuum TEM environment, with 21.4 nm for PEG and 51.2 nm for HPMCAS. While corrected average diameter agrees within 10% for each technique, DLS consistently over-estimates the standard deviation of the PSD by 100% compared to the TEM measurement.
Adequate characterization of NPs (nanoparticles) is of paramount importance to develop well defined nanoformulations of therapeutic relevance. Determination of particle size and surface charge of NPs ...are indispensable for proper characterization of NPs. DLS (dynamic light scattering) and ZP (zeta potential) measurements have gained popularity as simple, easy and reproducible tools to ascertain particle size and surface charge. Unfortunately, on practical grounds plenty of challenges exist regarding these two techniques including inadequate understanding of the operating principles and dealing with critical issues like sample preparation and interpretation of the data. As both DLS and ZP have emerged from the realms of physical colloid chemistry – it is difficult for researchers engaged in nanomedicine research to master these two techniques. Additionally, there is little literature available in drug delivery research which offers a simple, concise account on these techniques. This review tries to address this issue while providing the fundamental principles of these techniques, summarizing the core mathematical principles and offering practical guidelines on tackling commonly encountered problems while running DLS and ZP measurements. Finally, the review tries to analyze the relevance of these two techniques from translatory perspective.
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In this present investigation, an aqueous Basella alba leaves extract was used to synthesize AgNPs. The green synthesis approach is carried out in our work due to non-toxic, less cost, and ...ecofriendly methods. FTIR spectra are used to confirm the biomolecules present in B.alba leaves extract along with AgNPs and these compounds are responsible for Ag particle from micro to nanostructure. The FCC structure and crystalline nature of the AgNPs are analyzed with the help of XRD and TEM techniques respectively. DLS and Zeta potential techniques are carried out to find the size and stability of AgNPs respectively and UV is used to verify the presence of AgNPs in synthesized samples employing SPR peaks around 435 nm. The antioxidant studies expose eminent scavenging activity which ranges from 13.71% to maximum 67.88%. Green synthesized AgNPs possess well organized biological activities concerning antioxidant and antibacterial, which can be used in some biologically applications.
•Biological technique is cost-efficient, capable of processing AgNPs at 60 °C.•Synthesized AgNPs were spherical in size and the size ranging from 18 to 35 nm.•The feasible biomolecules which are liable for the minimization of Ag+ ions.•Alkyl halides bond reported that the indicates association of alkanes.•AgNPs reported that proteins could bind to silver nanoparticles which are compatible.
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•An incisively novel AIE active anthracene based fluorescent probe (AIN) is designed.•It furnishes strong green colour fluorescent aggregates in mixed aqueous media.•The fluorescent ...aggregates shows superb selectivity toward Hg2+ ion as low as ∼3 ppb.•The aggregates coated TLC strips detect Hg2+ ions for an instant ‘naked eye’ response.•It is also applied to determine the concentration of Hg2+ in real water samples.
An Anthracene based fluorescent probe, 1-(Anthracen-2-yliminomethyl)-napthalen-2-ol (AIN), was synthesized via simple one-pot reaction from inexpensive reagents. Intriguingly, it exhibited novel AIE characteristics in H2O-THF mixtures at high water content. Size and growth process of particles in different volume percentage of water and THF mixtures were investigated using TRPL, DLS, SEM and optical microscope. The fluorescent aggregates exhibited distinct Hg2+-selective “on-off” type fluorescence switching upon binding. Additionally, the fluorescence quenching showed a linear correlation in the Hg2+ concentration range from 0.3 to 3.6 μM and the limit of detection was estimated as low as ∼3 ppb. The drastic decrease in emission intensity of AIN aggregates was observed in the presence of mercury ions via a complex interplay through the ground state complexation between AIN and Hg2+ ions and external heavy atom induced perturbation by Hg2+ ions to the excited states of the AIN. A large Stern–Volmer quenching constant was estimated to be 2.54 × 105 M−1. The proposed analytical system with clear AIE characteristics demonstrates a potential outlook for the on-site visual detection of Hg2+ in paper strips. Finally, the sensory probe was also applied to determine the concentration of Hg2+ in real water samples to demonstrate its practical applications.
•Interactions of polyphenols with yeast protein extract, mannoproteins and β-glucans.•Binding experiments, titration calorimetry and dynamic light scattering studies were done.•Higher interactions ...for yeast protein extract than mannoproteins.•No interaction leading to the formation of aggregates with β-glucan.•Strong impact of the polyphenol structures and protein content on the interactions.
At present, there is a great interest in enology for yeast derived products to replace aging on lees in winemaking or as an alternative for wine fining. These are yeast protein extracts (YPE), cell walls and mannoproteins. Our aim was to further understand the mechanisms that drive interactions between these components and red wine polyphenols. To this end, interactions between grape skin tannins or wine polyphenols or tannins and a YPE, a mannoprotein fraction and a β-glucan were monitored by binding experiments, ITC and DLS. Depending on the tannin structure, a different affinity between the polyphenols and the YPE was observed, as well as differences in the stability of the aggregates. This was attributed to the mean degree of polymerization of tannins in the polyphenol fractions and to chemical changes that occur during winemaking. Much lower affinities were found between polyphenols and polysaccharides, with different behaviors between mannoproteins and β-glucans.
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