Fourier Transform Infrared Spectra Research Articles

Bimetallic nanoparticles with sulfated galactan eliminate Vibrio parahaemolyticus in shrimp Penaeus vannamei

Bimetallic (Au/Ag) nanoparticles (BNPs) have shown enhanced antibacterial activity compared to their monometallic counterparts. Sulfated galactans (SG) are a naturally occurring polymer commonly found in red seaweed Gracilaria fisheri. They are biocompatible and biodegradable and environmentally friendly. In this study, we utilized SG in combination with BNPs to develop composite materials that potentially enhance antibacterial activity against shrimp pathogens Vibrio parahaemolyticus and Vibrio harveyi, compared to BNPs or SG alone. BNPs were coated with sulfated galactan (SGBNPs) and characterized using UV-vis spectroscopy, Fourier transform infrared (FTIR) spectroscopy, zeta potential, and transmission electron microscopy (TEM). UV-vis spectroscopy analysis revealed that the surface plasmon peaks of BNPs and SGBNPs appeared at 530 nm and 532 nm, respectively. Zeta potential measurements showed that SGBNPs had a negative charge of -32.4 mV, while the BNPs solution had a positive charge of 38.7 mV. TEM images demonstrated the spherical morphology of both BNPs and SGBNPs with narrow size distributions (3-10 nm). Analysis of the FTIR spectra indicated that SG maintained its backbone structure in SGBNPs, but some functional groups were altered. Notably, SGBNPs showed superior antimicrobial and antibiofilm activities against V. parahaemolyticus and V. harveyi compared to SG and BNPs. Furthermore, treatment with SGBNPs significantly down-regulated the expression of virulence-related genes (toxR, cpsQ, and mfpA) for V. parahaemolyticus 3HP compared to the respective control, bacteria treated with BNPs or SG. Diets supplemented with SGBNPs, BNPs, or SG showed no detrimental impact on the growth of shrimp Penaeus vannamei. Shrimp fed with SGBNPs-supplemented feed showed significantly higher survival rates than those fed with BNPs-supplemented feed when infected with 3HP after being on the supplemented feed for seven days and a subsequent number of fifteen days. These findings collectively demonstrate the benefit of using SG capped Au-Ag BNPs as an antibacterial agent for the prevention and control of Vibrio sp. infection in shrimp while reducing the risk of environmental contamination.

Study of Microstructure, Morphology and Functional Groups of Titanium Dioxide (Tio2) Impregnated With Copper (Cu)

This research aims to determine the differences in the microstructure, morphology, and functional groups of TiO2 (P-25) after being impregnated with Cu. Cu-impregnated TiO2 samples are synthesized using the impregnation method with TiO2 (P-25) and copper sulfate as precursors. The microstructure and functional groups of TiO2 (P-25) and Cu-TiO2 were investigated using X-ray diffraction (XRD), scanning electron microscope-energy dispersive x-ray (SEM-EDX), and Fourier transform infrared (FTIR) analysis. The lattice parameters (a, b, and c) of the TiO2 sample were found to be a = b = 0.3778 nm, c = 0.9494 nm, and these values increased to a = b = 0.3779 nm, c = 0.9496 nm after the addition of Cu. The distance between the lattices of the TiO2 sample was measured at 0.3505 nm and increased to 0.3509 nm after Cu addition. The average crystallite size of the TiO2 sample was 33 nm, which increased to 43 nm after Cu impregnation. The strain value decreased from 2.76×10^(-3) to 1.82×10^(-3) after Cu addition. SEM results revealed that the morphology of the particles from the Cu-doped synthesis showed agglomeration. The success of Cu doping was confirmed by EDX mapping, which showed the presence of Ti, O, and Cu evenly distributed on the TiO2 surface. The FTIR spectrum indicated that TiO2 (P-25) and Cu-TiO2 particles had absorption peaks at similar wave numbers. However, in the absorption area of 1000 cm^-1 to 1250 cm^-1, new absorption bands affiliated with Cu-O bonds appeared in the Cu-TiO2 sample, resulting from TiO2 vibrations after Cu addition.

In-Vitro Study of the Binding of Atorvastatin with Adenine using Multi-Spectroscopic Approaches.

Atorvastatin-an oral lipid regulating drug is a competitive inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase), which is the rate determining enzyme for cholesterol synthesis. Adenine is a purine nucleobase that is found in deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) to generate genetic information. The binding mechanism of atorvastatin and adenine was studied for the first time utilizing various techniques, including UV-visible spectrophotometry, spectrofluorimetry, synchronous fluorescence spectroscopy (SF), Fourier transform infrared (FTIR), fluorescence resonance energy transfer (FRET), and metal ion complexation. The fluorescence spectra of the complex indicated that atorvastatin is bound to adenine via hydrophobic interaction through a spontaneous binding process, and the fluorescence quenching mechanism was found to be static quenching with a binding constant of 1.4893 × 104 Lmol-1 at 298 K. Various temperature settings were used to investigate thermodynamic characteristics, such as binding forces, binding constants, and the number of binding sites. The interaction parameters, including the standard enthalpy change (ΔHο) and standard entropy change (ΔSο) were calculated using Van't Hoff's equation to be 42.82 kJmol-1 and 208.9 Jmol-1K-1, respectively. The findings demonstrated that the adenine- atorvastatin binding was endothermic. Furthermore, the results of the experiments revealed that some metal ions (K+, Ca+2, Co+2, Cu+2, and Al+3) facilitate the binding interaction between atorvastatin and adenine. Slight changes are observed in the FTIR spectra of adenine, indicating the binding interaction between adenine and atorvastatin.

An investigation of the structural and optical properties of modified barium magnesium fluoroborate glasses with hafnium oxide (HfO2)

AbstractGlasses of nominal composition xHfO2–(35-x)B2O3–15MgF2–35BaO, where x ranged from 0 to 0.2 mol% were fabricated using a melt-quenching technique. Structural characterization techniques, including X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, and Raman spectroscopy, were employed to elucidate the glass network structure. The XRD patterns confirmed the amorphous nature of the studied glasses, while the FTIR and Raman spectra revealed that the incorporation of HfO2 may led to a transformation of trigonal BO3 units to tetrahedral BO4 units in the borate glass network. Deconvolution analysis of the FTIR and Raman bands provided quantitative insights into the extent of this structural rearrangement as a function of HfO2 content. UV–Vis absorption studies demonstrated that the optical bandgap of the glasses was widened with increasing HfO2 additions. This blue shift in the absorption edge was attributed to the increased formation of bridging oxygen bonds and reduced non-bridging oxygen content in the glass network. The results indicate that the studied glasses exhibit excellent compositional tunability through the incorporation of HfO2. The structural modifications and concomitant optical property enhancements suggest the potential of this glass system for various integrated photonic applications where low phonon energy and tailored transparency are highly desirable. The present work introduces a comprehensive investigation of the structural and optical property modifications in barium magnesium fluoroborate glasses induced by the addition of hafnium oxide (HfO2).

Poly(butylene adipate-co-terephthalate)/thermoplastic canna starch (Canna edulis ker.) (PBAT/TPS) blend film – A novel biodegradable material

The PBAT (poly (butylene adipate-co-terephthalate) is a promising biodegradable material. However, it is often blend with hydrophilic polymers since its degradation rate in the aquatic environment is still limited. In this study, the blend PBAT/TPS (thermoplastic starch) films, namely BFs, were prepared by a blow extrusion approach, and evaluated for hydrolysis in four studied mediums acid (HCl, 1 M, 2 M, and 3 M), alkaline (NaOH, pH = 9, 11, and 13), phosphate buffer (pH = 7.4), and artificial seawater. The hydrolyzed BFs were characterized by weight loss, mechanical properties, scanning electron microscopy (SEM), Fourier transform infrared spectra (FTIR), and differential scanning calorimetry (DSC). A larger starch content in the BFs caused hydrolysis more quickly. The highest hydrolytic rate was found in the alkaline solution, followed by the acid medium. The complete abiotic hydrolysis of the BFs was 3 M HCl for 14 days or NaOH (pH 13) for 35 days. After 180 days of incubation, the film containing 70.5 % PBAT/TPS granules has been associated with the highest biodegradation rate of 76.31 % in composting.

Effect of nanodiamonds surface deposition on hydrophilicity, bulk degradation and in-vitro cell adhesion of 3D-printed polycaprolactone scaffolds for bone tissue engineering.

This study was designed to deposit nanodiamonds on 3D-printed PCL scaffolds and evaluate their effect on the surface topography, hydrophilicity, degradation, and in-vitro cell adhesion compared to untreated PCL scaffolds. The PCL scaffold specimens were 3D-printed by fused deposition molding (FDM) technique with specific porosity parameters. The 3D-printed specimens' surfaces were modified by nanodiamonds deposition followed by oxygen plasma post-treatment using a plasma focus (PF) device and a non-thermal atmospheric plasma jet (NTAPJ), respectively. Specimens were evaluated through morphological characterization by field emission scanning electron microscope (FESEM), microstructure characterization by Raman spectroscopy, chemical characterization by Fourier transform infrared (FTIR) spectroscopy, hydrophilicity degree by contact angle and water uptake measurements, and in-vitro degradation measurements (n=6). In addition, in-vitro bone marrow mesenchymal stem cells (BMSCs) adhesion was evaluated quantitatively by Confocal microscopy and qualitatively by FESEM at different time intervals after cell seeding (n=6). The statistical significance level was set at p ≤0.05. The FESEM micrographs, the Raman, and FTIR spectra confirmed the successful surface deposition of nanodiamonds on scaffold specimens. The nanodiamonds treated specimens showed nano-scale features distributed homogeneously across the surface compared to the untreated ones. Also, the nanodiamonds treated specimens revealed a statistically significant smaller contact angle (17.45 ±1.34 degrees), higher water uptake percentage after 24 h immersion in phosphate buffer saline (PBS) (21.56% ±1.73), and higher degradation rate after six months of immersion in PBS (43.92% ±0.77). Moreover, enhanced cell adhesion at all different time intervals was observed in nanodiamonds treated specimens with higher nuclei area fraction percentage (69.87% ±3.97) compared to the untreated specimens (11.46% ±1.34). Surface deposition of nanodiamonds with oxygen-containing functional groups on 3D-printed PCL scaffolds increased their hydrophilicity and degradation rate with significant enhancement of the in-vitro cell adhesion compared to untreated PCL scaffolds.

Preparation and Characterization of Sustained Release Risperidone Loaded Eudragit Microparticles by Spray-Drying Technique

The goal of this work was to create novel risperidone-containing spray-dried microparticles using Eudragit® L100, a methacrylic polymer. Microparticles were designed with controlled release and enhanced in-vitro effects in mind and were meant to be taken orally. Spray-drying was used to create Eudragit® L100 microparticles loaded with risperidone. Risperidone-loaded Eudragit® L100 was successfully prepared to treat mental/mood disorders, according to an investigation into its physicochemical properties in-vitro. Spray-drying was an effective method for producing Eudragit® L100 microparticles loaded with risperidone. Formulations displayed a suitable drug entrapment percentage or nearly 89.94%. The mean diameter of the nearly spherical and spherical microparticles ranged from 30 to 50 μm, and they had a smooth surface. The distinctive peak of risperidone loaded with Eudragit L100 was visible in the fourier-transformed infrared (FTIR) spectra, indicating that the medication was fully encapsulated in the polymer. The dissolution rate of risperidone-loaded microparticles was slower than that of the pure medication. The use of spray-dried risperidone microparticles as a practical oral drug delivery method for more effective and regulated risperidone release is supported experimentally by our results.

Electrochemical Performance of Polyaniline‐Polyvanadate‐Copper Nanomaterials for the Detection of Benzoic Acid

AbstractThe introduction of nanomaterials as modified electrode materials into the field of electrochemical sensing is expected to improve the reliability, sensitivity, selectivity and repeatability of electrochemical sensors in detecting pollutants in the water environment. In this study, copper vanadate nanomaterials (Cu3V2O7(OH)2·2H2O, referred to as CVO) and Cu3V2O7(OH)2·2H2O/polyyaniline (PANI) composite nanomaterials (referred to as CVO/PANI) are successfully prepared and characterized by Fourier transform infrared spectrum (FTIR), X‐ray traveling‐action (XRD), scanning electron microscopy (SEM) and high‐resolution transmission electron microscopy (HR‐TEM). The modified glassy carbon electrodes (GCE) with these two materials are used for the detection of benzoic acid (BA) and exhibit excellent electrochemical sensing performance. The results show that two pairs of semi‐reversible redox peaks exist in both CVO and CVO/PANI modified glassy carbon electrode (GCE) in BA solution. The linear range of CVO and CVO/PANI nanomaterials‐modified GCE is 0.01–2 mm and 0.001–2 mm, and the limits of detection are 2.16 and 0.41 µm, respectively. PANI plays important role in the electrochemical responses of BA at CVO/PANI modified GCE. PANI enhances the intensities of CV peaks and electrochemical determination ability for BA.

Brucella pituitosastrain BU72, a new hydrocarbonoclastic bacterium through exopolysaccharide-based surfactant production.

Hydrocarbon and heavy metal pollution are amongst the most severe and prevalent environmental problems due to their toxicity and persistence. Bioremediation using microorganisms is considered one of the most effective ways to treat polluted sites. In the present study, we unveil the bioremediation potential of Brucella pituitosa strain BU72. Besides its ability to grow on multiple hydrocarbons as the sole carbon source and highly tolerant to several heavy metals, BU72 produces different exopolysaccharide-based surfactants (EBS) when grown with glucose or with crude oil as sole carbon source. These EBS demonstrated particular and specific functional groups as determined by Fourier transform infrared (FTIR) spectral analysis that showed a strong absorption peak at 3250 cm-1 generated by the -OH group for both EBS. The FTIR spectra of the produced EBS revealed major differences in functional groups and protein content. To better understand the EBS production coupled with the degradation of hydrocarbons and heavy metal resistance, the genome of strain BU72 was sequenced. Annotation of the genome revealed multiple genes putatively involved in EBS production pathways coupled with resistance to heavy metals genes such as arsenic tolerance and cobalt-zinc-cadmium resistance. The genome sequence analysis showed the potential of BU72 to synthesise secondary metabolites and the presence of genes involved in plant growth promotion. Here, we describe the physiological, metabolic, and genomic characteristics of Brucella pituitosa strain BU72, indicating its potential as a bioremediation agent.

Evaluation of the potential of Yushina alpina bamboo fibers from Cameroon for the manufacture of biocomposites

The Cameroon has two bamboo species indigenous to Africa (the alpine bamboo, Yushina alpina and the savannah bamboo, Oxytenanthera abyssinica), and one largely exotic species, Bambusa vulgaris. However, little on their physical characteristics and strength for the composites materials applications is known for these two indigenous bamboos species in Cameroon. Therefore, in this study, emphasis was laid on the alpine bamboo Y. alpina, to evaluate its potential for biocomposites applications. Y. alpina with ages ranging from 1 to 3 years, 4–5 years, and 7 years were characterized. The mechanical and physical properties of these three age ranges were compared. In the first place, the surface texture of the fibers was examined by scanning electron microscopy. Afterwards, chemical treatment was performed on the fibers with 1 % NaOH. In addition, the chemical bonds of the molecules (functional groups) were identified by Fourier transform infrared spectra (FTIR) and the thermal properties of the fibers were examined with a thermogravimetric analyzer. Furthermore, the fibers density was assessed using the Rilem protocol and a tensile testing machine was used to determine the mechanical properties of the treated fibers with 1 % of NaOH. Finally, a dynamic mechanical analysis of 7-year-old Y. alpina fibers was carry out. The results indicate that the Young's modulus of treated fibers with ages ranging from 1 to 3 years, 4–5 years, and 7 years were around 18 GPa, 10 GPa, and 14 GPa, respectively. In summary, this study underlines two primary points: (1) providing a platform for researchers to better understand the influence of age on the physical and mechanical properties of indigenous bamboo Y. alpina; and (2) providing a platform to validate suitable designs of biocomposites materials with Y. alpina.

A novel photocatalytic degradation of mixed dye through chemically synthesized ZnO/Fe2O3 nanocomposite.

This study reported the synthesis and assessment of zinc oxide/iron oxide (ZnO/Fe2O3) nanocomposite as photocatalysts for the degradation of a mixture of methylene red and methylene blue dyes. X-ray diffraction analysis confirms that the crystallite of zinc oxide (ZnO) has a hexagonal wurtzite phase and iron oxide (Fe2O3) has a rhombohedral phase. Fourier Transform Infra-Red spectrum confirms the presence of Zn-O vibration stretching at 428, 480 and 543cm-1 stretching confirming Fe-O bond formation. Scanning Electron Microscope images exhibited a diverse size and shape of the nanocomposites. The ZnO-90%/Fe2O3-10% and ZnO-10%/Fe2O3-90% nanocomposites reveal good photocatalytic activity with reaction rate constants of 1.5 × 10-2 and 0.66 × 10-2; and 1.3 × 10-2 and 0.60 × 10-2 for methylene blue and methyl red dye respectively. The results revealed that the synthesized ZnO/Fe2O3 nanocomposite is the best catalyst for dye degradation and can be used for industrial applications in future.

Semi-Supervised Autoencoder for Chemical Gas Classification with FTIR Spectrum.

Chemical warfare agents pose a serious threat due to their extreme toxicity, necessitating swift the identification of chemical gases and individual responses to the identified threats. Fourier transform infrared (FTIR) spectroscopy offers a method for remote material analysis, particularly in detecting colorless and odorless chemical agents. In this paper, we propose a deep neural network utilizing a semi-supervised autoencoder (SSAE) for the classification of chemical gases based on FTIR spectra. In contrast to traditional methods, the SSAE concurrently trains an autoencoder and a classifier attached to a latent vector of the autoencoder, enhancing feature extraction for classification. The SSAE was evaluated on laboratory-collected FTIR spectra, demonstrating a superior classification performance compared to existing methods. The efficacy of the SSAE lies in its ability to generate denser cluster distributions in latent vectors, thereby enhancing gas classification. This study established a consistent experimental environment for hyperparameter optimization, offering valuable insights into the influence of latent vectors on classification performance.

New molecular and macroscopic understandings of novel green chemicals based on Xanthan Gum and bio-surfactants for enhanced oil recovery

This research investigates the interactions between a novel environmentally friendly chemical fluid consisting of Xanthan gum and bio-based surfactants, and crude oil. The surfactants, derived from various leaves using the spray drying technique, were characterized using Fourier-transform infrared (FTIR) spectroscopy, zeta potential analysis, Dynamic light scattering, and evaluation of critical micelle concentration. Static emulsion tests were conducted to explore the emulsification between crude oil and the polymer-surfactant solution. Analysis of the bulk oil FTIR spectra revealed that saturated hydrocarbons and light aromatic hydrocarbons exhibited a higher tendency to adsorb onto the emulsion phase. Furthermore, the increased presence of polar hydrocarbons in emulsion phases generated by polar surfactants confirmed the activation of electrostatic forces in fluid–fluid interactions. Nuclear magnetic resonance spectroscopy showed that the xanthan solution without surfactants had a greater potential to adsorb asphaltenes with highly fused aromatic rings, while the presence of bio-based surfactants reduced the solution's ability to adsorb asphaltenes with larger cores. Microfluidic tests demonstrated that incorporating surfactants derived from Morus nigra and Aloevera leaves into the xanthan solution enhanced oil recovery. While injection of the xanthan solution resulted in a 49.8% recovery rate, the addition of Morus nigra and Aloevera leaf-derived surfactants to the xanthan solution increased oil recovery to 58.1% and 55.8%, respectively.

First report of betalain production from endolichenic Bacillus sp. LDAB-1 from Dirinaria aegilita: Insights from novel quantification methodology of image processing.

Pigments are widely used in food supplements envisaging attractive colors along with health benefits. The desired advancements in the nutraceutical and antioxidant properties of pigments utilized in food products necessitate the search for novel additives. The present study is the first in the field to report the pigment-producing endolichenic bacteria, Bacillus sp. LDAB-1 from Dirinaria aegilita. Morphological, biochemical, and molecular characterization of the bacterium emphasizes that ideal pigment production occurs when utilizing sucrose and sodium nitrate. The pigment was salted out and dialyzed for further qualitative characterization using ultraviolet-visible, fluorescence, and Fourier transforminfraredspectra and the results corroborated the presence of betalains. The antioxidant activity of betalain is closer to the efficiency of α-tocopherol, which confers the pigment properties for antioxidant and nutraceutical significance. An optimal methodology for pigment affirmation is an issue when using an alternative methodology. Hence, the present assessment employs a comparative analysis of findings from both a spectrophotometric method and image processing technology encompassing RGB, CMYK, YCbCr, and L*a*b*color space models. Amongst these, the L*a*b* model potentially provides an effective modality for determining the pigment concentration. Bland-Altman plot analysis indicates similar consistency levels in betalain quantification by both methods at 95% confidence intervals, affirming the integrity and consistency of color image processing technology. Consequently, the present study represents novelty and innovativeness in reporting endolichenic Bacillus sp. LDAB-1 from D. aegilita and a rational image optimization protocol for pigment elucidation characteristics.

Investigating the adsorption of Malachite Green and Methyl Green onto synthesized Ni0.5Zn0.5Fe2O4 spinel ferrites

Investigating the adsorption of Malachite Green and Methyl Green onto synthesized Ni0.5Zn0.5Fe2O4 spinel ferrites

Synthesis and characterization of lemon leaf extract-mediated silver nanoparticles: An environmentally friendly approach with enhanced antibacterial efficacy

In this study, silver nanoparticles were synthesized using lemon leaf extract, which served as both a reducing and stabilizing agent. The synthesis process proved to be rapid, cost-effective, and environmentally friendly. The effect of the mixing ratio of the reactants was investigated. Optimal yield, approximately 70 %, was achieved at 60 °C with a 0.25 M silver nitrate solution interacting for 40 min with lemon leaf extract in a 1:1 (v/v) ratio. Confirmation of nanoparticle formation was achieved through visible color change, UV–visible spectra (UV–Vis), X-ray diffraction analysis (XRD), Fourier transform infrared spectra (FT-IR), zeta potential, scanning electron microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), and transmission electron microscopy (TEM). The UV–Vis spectrum of the aqueous medium containing silver nanoparticles showed an absorption peak at around 412 nm. FT-IR spectra had shown that the biomolecule compounds were responsible for the reduction and capping material of silver nanoparticles. The XRD study showed the particles displayed an average crystallite size ranging from 9.4 to 36 nm. SEM and TEM showed a face-centered cubic (FCC) structure with an average size of 34 nm. The stability was detected using zeta potential analysis. These nanoparticles were used as antibacterial agents against Escherichia coli and Methicillin-resistant Staphylococcus aureus (MRSA), and the effect of silver nanoparticle concentration was investigated. The results indicated the synthesized silver nanoparticles demonstrated significant antibacterial activity against E. coli and MRSA, with average inhibition zone diameters exceeding 17 mm for E. coli and 15 mm for MRSA. Remarkably, antimicrobial activity was observed against two tested microbes at extremely low concentrations of 1–3 mM of silver nanoparticles.

Optimization, characterization and evaluation of sodium alginate nanoparticles for Ganoderic acid DM encapsulation: Inhibitory activity on tyrosinase activity and melanin formation

The efficacy of nanoencapsulation as a technology for enhancing the solubility of active substances has been demonstrated. In this particular investigation, Ganoderic acid DM (GA-DM) was encapsulated within sodium alginate nanoparticles (NPs) using the ionic crosslinking method. The confirmation of the successful loading of GA-DM was ascertained through the analysis of Fourier transform infrared spectrum (FTIR). Empirical evidence derived from the examination of scanning electron microscope (SEM) images, transmission electron microscope (TEM) images, atomic force microscope (AFM) images, and dynamic light scattering (DLS) demonstrated a regular distribution and spherical morphology, with an average particle size of approximately 133 nm. The investigation yielded an encapsulation efficiency of 95.27 ± 0.11 % and a drug loading efficiency of 21.17 ± 0.02 % for the prepared sample. The release kinetics of SGPN was fitted with the Korsmeyer-Peppas kinetic model corresponding to diffusion-controlled release. The incorporation of GA-DM into sodium alginate nanocarriers exhibited a mitigating effect on the cytotoxicity of HaCat and B16, while also demonstrating inhibitory properties against tyrosinase activity and melanin formation.

Study on the efficacy and mechanism of treatment of manganese-containing wastewater by pulse-alternating current coagulation

ABSTRACT To assess the effectiveness and underlying mechanism of pulse-alternating current coagulation (PACC) for treating manganese-laden wastewater, we examined the influence of various parameters. Specifically, we investigated the impact of current density, initial pH, initial Mn2+ concentration, electrolyte concentration, and alternating current frequency on the removal efficacy. The removal mechanism was meticulously examined using an adsorption kinetics analysis, Scanning Electron Microscope (SEM), Energy Dispersive Spectroscopy (EDS), Fourier Transform Infrared Spectrum (FTIR), and X-ray Photoelectron Spectroscopy (XPS). The findings indicated that the concentration of Re (Mn2+) was 99.09% under the specified conditions: j = 2.5 A·m−2, pH0 = 7, c 0(Mn2+) = 50 mg·dm−3, f = 500 Hz, c 0(NaCl) = 500 mg·dm−3 and t = 40 min. When Re (Mn2+) = 98%, the energy consumption (EEC) was significantly lower for PACC at 1.23 kWh·m−3, compared to 1.52 kWh·m−3 for direct current condensation (DCC). This indicated a reduction in EEC by 19.1% when using PACC over DCC. The adsorption process of Mn2+ by the iron sol adheres to the principles of pseudo-second order kinetics. The primary component of flocs generated in the PACC process is α-FeOOH. The mechanism of Mn2+ removal in the PACC process involved the synthesis of Mn oxides, the formation of metal hydroxide precipitates and adsorption by nano-iron sol. This study provides a theoretical basis and technical support for the application of PACC technology in the field of manganese-containing wastewater treatment.

Impact of Artificial Weathering on Swimwear Fabric

Lately, being physically active has become a priority of daily life. Despite that outdoor sports boost an individual’s mental and physical health, it also generates the problem of ultraviolet light exposure. Clothes provide the wearer protection from the sun, but they are also damaged while completing this task. Therefore, the impact of ultraviolet aging on swimwear fabric, which is the most exposed type of garment to the sunrays, was investigated in this study. Changes in breaking force, elongation at break, air permeability, fabric elasticity and stiffness, and dimensional characteristics were examined after 120 and 240 h of artificial weathering, together with scanning electron microscope (SEM) images and Fourier-Transform Infrared (FTIR) spectroscopy. The influence of seawater treatment was explored as well. The results presented that breaking force, elongation at break, fabric elasticity and stiffness, and air permeability were dramatically influenced by ultraviolet exposure. No chemical destruction was observed in FTIR spectra, while micro-damages were detected in SEM images. Furthermore, it was concluded that the main detrimental parameter was UV radiation, and the effect of seawater treatment was usually found to be minimal or not distinctive. Due to the limited number of research on the impact of UV aging on warp-knitted swimwear, this study is expected to contribute to the related literature.

Effect of Chitosan Addition on Porosity of Rice Husk Calcium Silicate Used for Free Fatty Acid Adsorbent from Palm Oil

Studies have been done on developing calcium silicate pores derived from rice husk with and without including chitosan as a template. The chitosan solution was supplemented with sodium silicate derived from rice husk, and then CaCl2 was added. The calcium silicate was calcinated at 900ºC for 4 h. The calcium silicate obtained was characterized using X-ray diffraction (XRD), fourier transform infrared (FT-IR), and Brunauer-Emmett-Teller (BET) analysis. The XRD analysis showed the presence of diffraction peaks corresponding to Wollastonite (CaSiO3) crystals, Wollastonite 2m (CaSiO3), Alite (Ca3SiO5), and larnite (Ca2SiO4). Next, the FT-IR spectrum exhibits Si-O-Si, Si-O-Ca, and Si-OH functional groups, suggesting the presence of calcium silicate material. The BET study of calcium silicate using chitosan templates revealed a pore size of 3.88 nm, a pore volume of 0.1577 cc/g, and a surface area of 81.1519 m2/g. The BET analysis results obtained differed from those of the BET analysis of calcium silicate conducted without using chitosan templates, which were 2.06 nm, 0.069 cc/g, and 13.531 m2/g, respectively. The developed mesoporous calcium silicate was employed as an adsorbent to decrease the concentrations of free fatty acids in palm oil. The acid-base titration method is used to evaluate quantities of free fatty acids. The results obtained from the computation of free fatty acid levels indicate a decline in the concentration of free fatty acids in palm oil. The concentration of free fatty acids derived from palm oil was 1.23%. Therefore, mesoporous calcium silicate-free fatty acids at a concentration of 1.06% resulted in an 86.1% reduction.