Fourier Transform Infrared Spectra Research Articles

FTIR study of light-induced proton transfer and Ca2+ binding in T82D mutant of TAT rhodopsin

Proton transfer reactions play important functional roles in many proteins, such as enzymes and transporters, which is also the case in rhodopsins. In fact, functional expression of rhodopsins accompanies intramolecular proton transfer reactions in many cases. One of the exceptional cases can be seen in the protonated form of marine bacterial TAT rhodopsin, which isomerizes the retinal by light but returns to the original state within 10−5 s. Thus, light energy is converted into heat without any function. In contrast, the T82D mutant of TAT rhodopsin conducts the light-induced deprotonation of the Schiff base at high pH. In this article, we report the structural analysis of T82D by means of difference Fourier transform infrared (FTIR) spectroscopy. In the light-induced difference FTIR spectra at 77 K, we observed little hydrogen out-of-plane vibrations for T82D as well as the wild-type (WT), suggesting that the planar chromophore structure itself is not the origin of the reversion from the K intermediate in WT TAT rhodopsin. Upon relaxation of the K intermediate, T82D forms the following intermediate, such as M, whereas K of WT returns to the original state. Present FTIR analysis revealed the proton transfer from the Schiff base to D82 in T82D upon formation of the M intermediate. It is accompanied by the second proton transfer from E54 to the Schiff base, forming the N intermediate, particularly in membranes. The equilibrium between the M and N intermediates corresponds to the protonation equilibrium between E54 and the Schiff base. We also found that Ca2+ binding takes place in T82D as well as WT but with 6 times lower affinity. An altered hydrogen-bonding network would be the origin of low affinity in T82D, where deprotonation of E54 is involved in the Ca2+ binding.

Spectral analysis and characterization of Na2O-SiO2-ZrO2 glasses doped with V2O5

Na2O-SiO2-ZrO2 glasses doped with V2O5 were prepared with the melt quenching method, and were then analyzed using various techniques; in particular, with X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), and optical absorption, photoluminescence, electron spin resonance (ESR), and Fourier transform infrared (FT-IR) transmission spectroscopy. The obtained results indicate that, in the studied glasses, vanadyl complexes tend to undergo a reduction from V5+ ions to V4+ ions. XRD and EDS data suggest that the glasses have amorphous nature with randomly distributed grains within the glass matrix. The optical absorption spectra show two transitions: 2B2g→2B1g and 2B2g→2Eg. The photoluminescence spectra exhibit a broad band from 750-900 nm, indicating the 2E→2T2 transition of vanadyl ions. The energies of the band gaps decreased gradually with increasing V2O5 content. The ESR spectra suggest that V4+ ions are situated in octahedral sites with tetragonal compression. The FT-IR spectra confirm the presence of various structural units within the glasses. Finally, the dielectric properties of the glasses were also measured, showing that the dielectric constant (ε′) and the loss tangent (tan δ) increase as the content of vanadium ions increases, indicating presence of V4+ ions within the glass matrix.

Reutilization of post-adsorption lanthanum-loaded straw alleviates phosphorus pollution in rice-wheat system: Subsequent performance and underlying mechanisms

Adsorption technology for phosphorus (P) removal is considered promising and reutilization of post-adsorbent can contribute to promoting sustainable agricultural production. However, the long-lasting impact of the post-adsorbent on crop growth and P remains unclear. This study assessed the effects of P-adsorbed lanthanum-modified straw (La@straw-P) on the rice yield, P fractionation and associated water quality parameters. The findings indicated that, compared with traditional fertilizer regimes, La@straw-P expedited the P reduction in the flooding water achieving a rate of decline to the tertiary standard for surface water (0.20 mg/L) 3.8 times faster and enhanced increased the P harvest index by 17.00 %. Economic estimation proved the positive benefits of La@straw-P in planting-breeding combination system. Redundancy analysis (RDA) and co-occurrence network analysis (CONA) revealed that electrical conductivity (EC) and dissolved Fe played primary roles in regulating total P. Fourier transform infrared spectra (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectra (XPS), and soil P fractions collectively demonstrated that the abundant adsorption sites on La@straw-P could facilitate the transformation of active P into moderately Ca-bound P. This study proposes a strategy for recycling P-adsorbed materials to mitigate agricultural non-point P pollution.

Tagetes erecta-Mediated Biosynthesis of Mn3O4 Nanoparticles: Structural, Electrochemical, and Biological Investigations.

Mn3O4 nanoparticles (NPs) find diverse applications in the fields of medicine, biomedicine, biosensors, water treatment and purification, electronics, electrochemistry, and photoelectronics. The production of Mn3O4 NPs was reported earlier through various physical, chemical, and green routes, but no studies have still been performed on their biosynthesis from Tagetes erecta. We synthesized manganese oxide NPs, i.e., (Mn3O4)L and (Mn3O4)P NPs, by utilizing leaves and petals, respectively, of T. erecta as reducing and stabilizing agents. The investigated green path is eco-friendly and does not involve any hazardous raw materials. The structural properties of NPs were determined by X-ray diffraction (XRD) analysis, spectroscopies (Fourier transform infrared (FTIR), Raman, and UV-visible), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The NPs were also evaluated for their electrochemical properties by cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD). XRD analysis was performed to verify their tetragonal geometry, and the crystallite size (19.24 nm) of (Mn3O4)P was smaller than that (20.84 nm) of (Mn3O4)L NPs. SEM images displayed a porous and spherical morphology with a diameter of 14-35 nm. FTIR spectra of (Mn3O4)L and (Mn3O4)P displayed Mn-O vibrations at 605.69 and 616.87 cm-1, respectively, and the hydrous nature of the material. Raman spectroscopy revealed the existence of tetrahedral and octahedral units along with A1g, T2g, and Eg active modes of Mn3O4 and 2TO mode. UV-visible analyses of (Mn3O4)L and (Mn3O4)P NPs showed absorption peaks at 272.3 and 268.8 nm, along with band gaps of 4.83 and 5.49 eV, respectively. TGA curves displayed good thermal stabilities up to 600 °C and a loss of moisture content. DSC curves exhibited exothermic/endothermic peaks with glass transition temperatures of 258.9 and 308.7 °C for (Mn3O4)P and (Mn3O4)L, respectively. The CV curves showed redox peaks and confirmed that the electrochemical reaction takes place in the Mn3O4 material. GCD scans revealed the capacitive behavior of NPs and their suitability as electrodes in energy storage devices. However, (Mn3O4)L will act as a good material for energy storage applications as compared to (Mn3O4)P NPs. The synthesized NPs were also tested for their antibacterial efficacy by biofilm inhibition and agar well diffusion methods. The NPs showed higher activities against Staphylococcus aureus (Gram-positive) than against Escherichia coli (Gram-negative), and (Mn3O4)P was more bioactive than (Mn3O4)L.

Evaluation of spectroscopic techniques for on-site drug testing of festival seizures.

Despite the fact that drugs of abuse are illegal, a drug-free festival still remains an utopia in most settings. For law enforcement purposes, it is necessary to rapidly determine whether controlled substances are involved. On-site testing is a challenging task because drugs appear in different physical forms and concentrations. The aim of this study was to compare the performance of two spectroscopic techniques, Raman and Fourier transform-infrared (FT-IR), for the testing of drug seizures at a dance festival. First, samples were measured through packaging with Raman. Subsequently, homogenized samples were analysed with FT-IR. For MDMA tablets, a chemometric model was applied on the FT-IR spectra for the dose estimation. After the festival, results were confirmed in the forensic laboratory with gas chromatography coupled with mass spectrometry (GC-MS) and gas chromatography with flame ionization detection (GC-FID). In total, 166 samples of which 90 tablets, 53 powders, 16 crystals and 7 liquids were analysed. MDMA, cocaine and ketamine were the top three drugs seized. The Raman technique was suitable for powders and crystals (sensitivity of 100% and 81%, respectively). However, in comparison with FT-IR, Raman performance was lower for the analysis of liquids (sensitivity of 67%) and 'ecstasy'-like tablets (sensitivity of 41%). Overall, sensitivities above 95% were obtained with FT-IR. The MDMA doses of the tablets, determined on-site, ranged between 52 mg and 336 mg MDMA hydrochloride. For a quick identification of a variety of drugs on-site, the combination of Raman and FT-IR is recommended. It should be emphasized that optimized settings, in-house libraries and analysis by trained operators are essential to obtain correct results.

Photocatalyst based on composite of trimetallic metal-organic frameworks for efficient visible-light degradation in pharmaceutical pollutants abatement and process modeling using RSM

In this study, the facile synthesis of both monometallic Co- Metal-Organic Frameworks bimetallic Ni-Co-Metal-Organic Frameworks and trimetallic Ni-Co-Cu-Metal-Organic Frameworks was successfully accomplished with the chelation method. The prepared samples were characterized by using X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), N2 adsorption–desorption, Fourier transform infrared spectra (FTIR), differential reflectance spectroscopy (UV–vis-DRS), and photoluminescence (PL) techniques was undertaken to examine the physicochemical attributes of the synthesized composites. The photocatalytic efficiency of the antibiotic ceftazidime(CAZ) degradation was investigated under visible light irradiation in 100 min. Kinetic studies revealed a pseudo-first-order model (50.0143, 0.009, and 0.0057 min−1 for Co-MOF, Co-Ni-MOF, and Co-Ni-Cu-MOF, respectively). Response surface methodology (RSM) demonstrated satisfactory predictability for CAZ degradation efficiency. Under optimized conditions (pH 10, 0.25 g L−1 catalyst) more than 97.38 % for the 20.0 mg L−1 of CAZ was degraded. Furthermore, the recyclability and scavenging test for the catalyst was evaluated.

Synergistic Effects of Pea Protein on the Viscoelastic Properties of Sodium Alginate Gels: Findings from Fourier Transform Infrared and Large-Amplitude Oscillatory Shear Analysis

The rheological characteristics of pea protein (PP100%) and alginate (AG100%) as pure and mixed gels with different levels of pea protein (AP90:10, AP80:20, and AP70:30) were investigated via large-amplitude oscillatory shear (LAOS) and Fourier transform infrared (FTIR). Small-angle oscillatory shear (SAOS) was carried out for the samples, and a slight frequency dependence of the storage modulus (G′) and the loss modulus (G″) was observed for the pastes and gels, indicating the formation of a weak network, which is crucial for understanding the gel’s mechanical stability under small levels of deformation. Elastic and viscous Lissajous curves from the LAOS measurement at different levels of strain (1 to 1000%) elucidated that the mixed gels formed a strong network, which showed breakdown at high deformation (>100% strain). The synergistic strengthening of the network of the mixture was noticeable in the Fourier transform and Chevyshev harmonic analyses. This analysis indicated that the nonlinearity of e3/e1 and v3/v1 started at higher levels of strain for the mixed gels. The FTIR spectra revealed that there was no strong interconnection by crosslinking between pea protein and sodium alginate, indicating that the synergistic effect mainly came from electrostatic interactions. These findings suggest that combining alginate with pea protein can enhance the mechanical properties of gels, making them suitable for various food applications.

Enhanced electrochemical performance of nickel cobalt sulfide microspheres for high energy symmetric supercapacitors

Herein, Nickel cobalt sulfide (NCS) microspheres are successfully synthesized by an easy one-step hydrothermal method at different reaction conditions. The as-synthesized samples are used as electrode material to demonstrate their practical application for supercapacitors (SCs). Various techniques including X-ray diffraction (XRD), Fourier transform infrared spectra (FTIR), Scanning electron microscopy (SEM), Energydispersive X-ray (EDX) spectroscopy are used for structural and morphological characterization of the synthesized materials which confirmed the successful formation of NCS. The electrochemical performance of prepared samples is tested using cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) and electrochemical impedance spectroscopy (EIS). The optimized NCSW-200 sample delivered a remarkable specific capacitance of 369 F g−1 at 0.5 A g−1. The energy and power density exhibited by NCSW-200 sample are as high as 32.8 Wh kg−1 and 266.6 W kg−1, respectively. After 2000 consecutive charge/discharge cycles, capacitance retention of 67% is achieved, depicting better cyclic stability. To illustrate the practical feasibility of the prepared symmetric cells of the optimized sample NCSW-200, a lab scale setup of three SC cells connected in series is fabricated and tested using a red light emitting diode (LED). The SC setup is able to illuminate a red LED for 2.5 minutes. The electrochemical performance demonstrated by NCS microspheres suggests its viable application as supercapacitor electrodes.

Antioxidant response of Calendula officinalis L. assisted synthesized zinc oxide nanoparticles

The over-production of free radicals in the body causes oxidant damage in the body. Currently, zinc oxide nanoparticles (ZnO NPs) are gaining attention of most scientists because of their excellent physical, chemical, and biological properties. In this work, the ZnO NPs were synthesized using the petal extract of C. officinalis L. An absorbance spectrum of the synthesized ZnO NPs was recorded using an ultraviolet-visible (UV–Vis) spectrophotometer. The absorbance band around 368 nm confirms the formation of ZnO NPs. The transmission electron microscopy (TEM) analysis clearly shows that the most of the ZnO NPs are spherical in shape with average particle size ∼ 16 nm. The field emission scanning electron microscope (FE-SEM) result demonstrates the spherical morphology with large agglomeration of the particles. The energy-dispersive x-ray spectroscopy (EDS) result confirms the presence of Zn in the synthesized NPs’. The x-ray diffraction (XRD) peaks represent the crystalline structure of the ZnO NPs with average particle size ∼ 27.22 nm. Fourier transform infra-red (FT-IR) spectrum of synthesized ZnO NPs was recorded in the range of 4000-500 cm−1. The ester and carboxylic groups were found at 1017 cm−1, 952 cm−1, 688 cm−1, 609 cm−1, and 514 cm−1 due to the presence of Zn-O band stretch in the FT-IR spectrum. Further synthesized material was evaluated by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay to evaluate its antioxidant activity. It showed that ZnO NPs exhibited significant antioxidant activity through scavenging DPPH free radicals. Thus, it could be seen that the synthesis of naturally occurring plant product ZnO NPs acts as an alternative chemical antioxidant. Hence, the herbal synthesized ZnO NPs are proven to be a potent antioxidant agent and can be used in several medicinal applications.

CaCl2 doping effect on optical and structural properties of halide perovskites under ligand assisted reprecipitation synthesis

The high potential of metal halide perovskite (MHP) nanocrystals with the general formula CsPbX3 (X = Cl, Br, and I) has led to the development of easy and cost-effective methods on a daily basis. The room temperature (RT) and open atmosphere ligand-assisted reprecipitation (LARP) methods were utilized to synthesize CsPbBr3 and CsPbBr2I nanocrystals (NCs). CaCl2 was used as a dopant in four different concentrations (0.25, 0.5, 0.75, and 1 % molar) to optimize the optical and electrical properties and to enhance the stability of NCs. The most optimal results were observed with 0.25 % doping for CsPbBr2I and 0.75 % doping for CsPbBr3. XRD and FE-SEM analyses revealed a cubic crystal structure for the synthesized nanocrystals. Dynamic light scattering (DLS) analysis indicated an average size of was 35–70 nm. The introduction of Ca2+ impurity, resulted in increased sizes for 0.75 % doped CsPbBr3 NCs; and increased intensity for 0.25 % doped CsPbBr2I NCs. Optical studies, including UV–vis, Fourier Transform Infrared (FTIR), and photoluminescence spectroscopies were conducted. The bandgap of CsPbBr2I and CsPbBr3 was estimated at 2.60 and 2.75 eV, respectively. The FTIR spectra suggested the effective involvement of the ligand agents oleic acid (OA) and oleylamine (OLA) in synthesis of metal halide perovskite nanocrystals. Photoluminescence spectroscopy demonstrated that the photoluminescence intensity of CsPbBr2I and CsPbBr3 varied with impurity doping, indicating an enhancement of semiconductor electronic properties under Ca2+ doping.

Porphyrin Photosensitizers into Polysaccharide-Based Biopolymer Hydrogels for Topical Photodynamic Therapy: Physicochemical and Pharmacotechnical Assessments.

Photodynamic therapy (PDT) is an emerging treatment modality that utilizes light-sensitive compounds, known as photosensitizers, to produce reactive oxygen species (ROS) that can selectively destroy malignant or diseased tissues upon light activation. This study investigates the incorporation of two porphyrin structures, 5-(4-hydroxy-3-methoxyphenyl)-10,15,20-tris-(4-acetoxy-3-methoxyphenyl) porphyrin (P2.2.) and 5,10,15,20-tetrakis-(4-acetoxy-3-methoxyphenyl) porphyrin (P2.1.), into hydroxypropyl cellulose (HPC) hydrogels for potential use in topical photodynamic therapy (PDT). The structural and compositional properties of the resulting hydrogels were characterized using advanced techniques such as Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), atomic force microscopy (AFM), UV-Visible (UV-Vis) spectroscopy, and fluorescence spectroscopy. FTIR spectra revealed a slight shift of the main characteristic absorption bands corresponding to the porphyrins and their interactions with the HPC matrix, indicating successful incorporation and potential hydrogen bonding. XRD patterns revealed the presence of crystalline domains within the HPC matrix, indicating partial crystallization of the porphyrins dispersed within the amorphous polymer structure. TGA results indicated enhanced thermal stability of the HPC-porphyrin gels compared to 10% HPC gel, with additional weight loss stages corresponding to the thermal degradation of the porphyrins. Rheological analysis showed that the gels exhibited pseudoplastic behavior and thixotropic properties, with minimal impact on the flow properties of HPC by P2.1., but notable changes in viscosity and shear stress with P2.2. incorporation, indicating structural modifications. AFM imaging revealed a homogeneous distribution of porphyrins, and UV-Vis and fluorescence spectroscopy confirmed the retention of their photophysical properties. Pharmacotechnical evaluations showed that the hydrogels possessed suitable mechanical properties, optimal pH, high swelling ratios, and excellent spreadability, making them ideal for topical application. These findings suggest that the porphyrin-incorporated HPC hydrogels have significant potential as effective therapeutic agents for topical applications.

Qualitative Analysis and Anti-oxidant Potential of Ethanolic Extract ofManilkara zapota (L.) P. Royen Leaves

Background: The normal metabolic functioning of aerobic cells is related to free radical formation. The oxygen utilized in the cell growth gives rise to a number of oxygen free radicals. Further, these oxygen free radicals interact with lipidic molecules to produce hydroxyperoxides and various other peroxides also, radicals like superoxide, hydroxyls, and lipoid peroxides, which lead to cytotoxicity due to their interaction with biological systems. The uncontrolled generation of free radicals may lead to various diseases and disorders like prostate cancer, coronary heart disease and also ageing. The therapeutic potential of the plant M. zapota has been demonstrated in various diseases, such as cancers (e.g., breast, prostate, cervical, and hepatocellular cancer), diabetes mellitus, arthritis, bacterial infections, and gastrointestinal disorders (e.g., diarrhea and ulcers) and many medical conditions. The main phytocomponents of this plant are polyphenols, alkaloids, glycosides, flavonoids, saponins, triterpenoids, carbohydrates, tannins, and sterols. Objective: The objective of this study is to investigate qualitative analysis and anti-oxidant potential of ethanolic extract of Manilkara zapota (L.) P. Royen Leaves. In demand to minimize the damage caused by free radicals. It is very essential to develop such antioxidants which protect the body from the effect of free radicals and also do not cause much harm to the human body. The main phytocomponents of the plant are polyphenols, alkaloids, glycosides, flavonoids, saponins, triterpenoids, carbohydrates, tannins and sterols which are responsible for antioxidant activity. Materials and Methods: Phytochemical screening methods, Gas chromatography–mass spectrometry (GC-MS), Fourier transform infrared (FTIR), and Hydrogen Peroxide scavenging assay for analysis of an ethanolic extract of plant leaves. Results and Discussion: Antioxidant activity was determined by a hydrogen peroxide assay. Plant extract was examined using phytochemical screening, GC-MS analysis, and FTIR spectra. The plant extract showed hydrogen peroxide scavenging activity (IC50 = 16.45 μg/ml) compared to the IC50 values of standard ascorbic acid (IC50 = 9.079 μg/ml). Conclusion: The present study concluded the antioxidant and phytochemical assessment of the ethanolic extract of the leaves of Manilkara zapota. The results of the present research study demonstrated that the antioxidant activity of the plant extract was strong as compared to ascorbic acid.

Enhanced adsorption of ciprofloxacin from an aqueous solution using a novel CaMgAl-layered double hydroxide/red mud composite

This work reports on CaMgAl-layered double hydroxide (LDH) based red mud (RM) composite prepared via a co-precipitation method, characterized by transmission electron microscopy (TEM), powder X-ray diffraction patterns (XRD), field-emission scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), Brunauer-Emmett-Teller analysis (BET), and Fourier transform infrared spectra (FTIR) and subsequently used for elimination of ciprofloxacin (CIP) from an aqueous solution in batch mode experiments. Langmuir isotherm model provided a better fit of CIP adsorption onto CaMgAl/RM composites than a Freundlich isotherm model; indicating a monolayer adsorption phenomena. Pseudo-second-order kinetic models describe the kinetics of adsorption while the adsorption mechanisms were controlled by external mass transfer and intra-particle diffusion. Thermodynamic analysis indicated that the CIP adsorption onto CaMgAl-LDH/RM was exothermic and spontaneous in nature. The prepared adsorbent exhibited superior affinity towards CIP adsorption which yielded a maximum CIP adsorption capacity of up to 138 mg/g. The higher removal efficiency (89.45 %) was reached under the best conditions (pH 7, agitation speed 150 rpm, adsorbent dosage 0.5 g/100 ml, concentration of contaminant 70 ppm, and 90 min contact time). Moreover, the synthesized adsorbent can be recovered after six consecutive regeneration cycles with a minimal reduction in the adsorption ability of 31 %. In conclusion, this study demonstrated that the CaMgAl-LDH/RM composite could be a promising adsorbent for removing antibiotics from wastewater.

Influences of silicate modulus and alkali content on macroscopic properties and microstructure of alkali-activated blast furnace slag-copper slag

The stacking of copper slag (CS) has led to the resource wastage and environmental issues. Utilizing CS as a green precursor in the production of alkali-activated materials (AAMs) offers a promising avenue for sustainable resource usage. To obtain a deeper understanding and enhance its practical application, the effects of silicate modulus and alkali content of water glass (WG) on the performances of alkali-activated blast furnace slag-copper slag (AAS-CS) are systematically investigated though the fluidity, setting time, hydration heat, compressive strength and drying shrinkage rate. Additionally, the microstructure is characterized using nuclear magnetic resonance (NMR), X-ray diffraction (XRD), Fourier transform infrared spectrum (FTIR) and scanning electron microscope (SEM), respectively. When the alkali content is a constant of 6.0 wt%, the compressive strength and drying shrinkage rate initially increases with increasing silicate modulus, but eventually decrease beyond a certain threshold. At a given silicate modulus of 1.5, the compressive strength and drying shrinkage rate firstly increases and then decrease as increasing the alkali content from 4.0 wt% to 8.0 wt%. The microstructure analyses reveal that the suitable silicate modulus and alkali content promote the dissolution of precursors to form C-A-S-H gels. The M1.5N6.0 sample has a relatively tight microstructure, which benefits to the development of compressive strength, but increases the capillary stress. Therefore, the M1.5N6.0 sample has the highest 28-day compressive strength of 71.7 MPa and the largest 182-day drying shrinkage rate of 0.1532 %.

A comprehensive and innovative chemometric approach: Archaeometric analysis of the sherds from the Neolithic Period to the Chalcolithic and early Bronze Age with the full deployment of FTIR's molecular spectroscopic capabilities

In this study, the mineralogical composition of 284 sherds obtained from the sites of Yeşilova Höyük and Yassıtepe Höyük, two of the oldest settlements in Western Anatolia, and corresponding to a wide period starting from the Neolithic period to the Chalcolithic and Early Bronze Age (EBA), was studied by attenuated total reflectance (ATR) Fourier transform infrared (FTIR) spectroscopy. FTIR data was used to classify the sherds and state their firing conditions as a result of determining their mineralogical composition using principal component analysis (PCA), multivariate curve resolution (MCR), and hierarchical cluster analysis (HCA). According to the PCA results, the second-order derivative FTIR spectrum with 19 smoothing points in the range of 1300–400 cm−1 was determined to be the most successful model in classifying sherds. As a result of MCR, which allows comparison of standard minerals obtained within the scope of the study, it was determined that kaolinite, illite, chlorite, and some feldspar types were dominant in the sherds. According to HCA analysis, all sherds except five of them exhibited a similar mineralogical structure. According to the derivative spectra, it was seen that the sherds had a composition consisting of kaolinite, illite, hematite, chlorite, and some feldspar types at different rates. Upon examining the data, it becomes evident that the sherds are composed of nearly identical minerals and might have been fired in an oxidizing atmosphere. Even while 279 sherds had many mineralogical traits, N-061, EB-030, N-043, C-068, and N-059 were found to have distinct proportions of comparable minerals, including more kaolinite, illite, calcite, and chlorite. Regarding color, additives, and the amount of ceramic pastes present, these five sherds differ from the others. This suggests that there might have been attempts at manufacture or pots brought in from outside the Yeşilova Höyük-Yassıtepe Höyük sites. The results provided from the derivative spectra showed that all sherds except five of them have been fired at about at temperatures slightly above 450–500 °C due to their relatively low kaolinite character, but below 800 °C because diopside and similar high-temperature minerals could not be detected. The five sherds may have been fired at a temperature of around 450–500 °C due to the presence of a high character of kaolinite, illite, and chlorite. It was understood that the residents of the sites of Yeşilova Höyük and Yassıtepe Höyük produced their ceramics using the same raw materials and the same production methods from the Neolithic period to EBA thanks to FTIR and chemometrics, which are very good tools for analyzing large numbers of sherds with low cost and fast analysis time.

Glass transition temperature of Agar-Reduced Graphene Oxide (RGO) Composites using 2-D contour mapping of temperature dependent FTIR spectra

In the present work, composites of Reduced Graphene Oxide (RGO) and Agar have been synthesized via the solution cast method and their structural, thermal and dielectric properties are studied. UV–Visible, X Ray Diffraction (XRD), Raman Spectroscopy and Fourier Transform Infrared (FTIR) have been employed for analyzing structural properties of the prepared samples. Analysis of different peaks in XRD and Raman Spectra suggests the interaction of RGO layers with Agar at the molecular level. FTIR spectra indicate that interaction of Agar with RGO occurs through hydrogen bonding linkage. Further, the Glass transition temperature (Tg) of prepared samples has been determined using 2D contour mapping from temperature-dependent FTIR spectra as well as from the Differential Scanning Calorimetry (DSC)technique. Values of Tg obtained from both techniques have been found in close agreement with each other. In addition to that, value of Tg of Agar increases from 72 °C to 80 °C as an effect of 2 wt.% RGO loading indicating the improvement in the thermal behavior of Agar. Moreover, the dielectric behavior of as-prepared composites demonstrate that the dielectric constant of these composites has been increased in comparison to pure Agar.

Continuous Remediation of Congo Red Dye Using Polyurethane-Polyaniline Nano-Composite Foam: Experiment and Optimization Study

This study employed an innovative approach, utilizing prepared dried polyurethane-polyaniline nano-composite, through in-situ polymerization, for continuous remediation of Congo red dye. Response Surface Methodology (RSM) based on the Box-Behnken design (BBD) model was utilized to optimize the processing parameters, including initial dye concentration, flow rate, and pH. The two-factor interaction (2FI) model emerged as the most significant, highlighting the influence of individual and interaction effects of the factors. Optimization of the dye remediation process yielded the optimal conditions of a flow rate of 10 mL/min, acidic pH of 5.00, and dye concentration of 20 mg/L, resulting in an impressive, predicted removal efficiency of 99.09% agreeing with the experimental value. Moreover, the maximum adsorption capacity was determined to be 329.68 mg/g. Characterization of the adsorbent material involved techniques such as Scanning electron microscopy (SEM), Fourier transforms infrared spectra (FTIR), X-ray spectroscopy (XRD), and Zeta potential analysis. This material offers a sustainable alternative in industries to treat Congo red dye before being disposed of into the environment.

Preparation and characterization of conjugated PVA/PANi blend films doped with functionalized graphene for thermoelectric applications

Flexible nanocomposite thick films consisting of PVA0.7PANi0.3 polymer blend doped with different concentrations of nanoplatelets functionalized Graphene (NPFGx) (where x = 0, 5, 10, 15, 20, and 25 wt.%) were fabricated using the solution cast technique. Scanning electron microscopy (SEM), X-ray diffractometer (XRD), energy dispersive spectroscopy analysis (EDX), and Fourier-transform infrared spectra (FT-IR) were used to study the structure of the samples. The results showed that the ordered structure, its orientation, the PANis' well dispersion, and the electrostatic forces play a significant role in enhancing the interfaces between the polymer blend and the NPFG. Thermogravimetric analyses (TGA) and Thermoelectrical analyses (TE) showed that the PVA-PANi conducts a promised conjugated blend for thermoelectric applications. The introduction of the NPFG contents into the blend increased the TE measurements as the DC electrical conductivity ≈ 0.0114 (S cm−1), power factor ≈ 3.93 × 10–3 (W m−1 K−2), and Z.T. ≈ 8.4 × 10–7, for the 25 wt.% NPFG nanocomposite film. The effect of the polymers’ phonon contribution in the thermal conductivity controlling and enhancing the thermal stability of the prepared nanocomposite films.

Insights on early response to acute heat shock of bovine mammary epithelial cells through a multimethod approach

Heat stress is a significant challenge in dairy cattle herds, affecting milk production and quality, and generating important changes at the cellular level. Most in vitro research on heat shock (HS) effects on dairy cow mammary cells was focused on medium-long-term effects. In recent years, Fourier transform-infrared (FT-IR) micro-spectroscopy has been increasingly used to study the effects of several external stresses on different cell lines, down to the level of single cellular components, such as DNA/RNA, lipids, and proteins. In this study, the possible changes at the biochemical and molecular level induced by acute (30 min-2 h) HS in bovine mammary epithelial (BME-UV1) cells were investigated. The cells were exposed to different temperatures, thermoneutral (TN, 37 °C) and HS (42 °C), and FT-IR spectra were acquired to analyse the effects of HS on biochemical characteristics of BME-UV1 cellular components (proteins, lipids, and DNA/RNA). Moreover, cell viability assay, reactive oxygen species production, and mRNA expression of heat shock proteins (HSPA1A, HSP90AA1, GRP78, GRP94) and antioxidant genes (SOD1, SOD2) by RT-qPCR were also analysed. The FT-IR results showed a change already at 30 min of HS exposure, in the content of long-chain fatty acids, which probably acted as a response to a modification of membrane fluidity in HS cells compared with TN cells. After 2 h of HS exposure, modification of DNA/RNA activity and accumulation of aggregated proteins was highlighted in HS cells. The gene expression analyses showed the overexpression of HSPA1A and HSP90AA1 starting from 30 min up to 2 h in HS cells compared with TN cells. At 2 h of HS exposure, also the overexpression of GRP94 was observed in HS cells. Acute HS did not affect cell viability, reactive oxygen species level, and SOD1 and SOD2 gene expression of BME-UV1 cells. According to the results obtained, cells initiate early defence mechanisms in case of acute HS and probably this efficient response capacity may be decisive for tolerance to heat stress of dairy cattle.

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 (NDs) on 3D-printed poly-ϵ-caprolactone (PCL) scaffolds and evaluate their effect on the surface topography, hydrophilicity, degradation, andin-vitrocell adhesion compared to untreated PCL scaffolds. The PCL scaffold specimens were 3D-printed by fused deposition modeling (FDM) technique with specific porosity parameters. The 3D-printed specimens' surfaces were modified by NDs deposition followed by oxygen plasma post-treatment using a plasma focus device and a non-thermal atmospheric plasma jet, 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, andin-vitrodegradation measurements (n= 6). In addition,in-vitrobone marrow mesenchymal stem cells 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 atp⩽ 0.05. The FESEM micrographs, the Raman, and FTIR spectra confirmed the successful surface deposition of NDs on scaffold specimens. The NDs treated specimens showed nano-scale features distributed homogeneously across the surface compared to the untreated ones. Also, the NDs 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 NDs treated specimens with higher nuclei area fraction percentage (69.87 ± 3.97%) compared to the untreated specimens (11.46 ± 1.34%). Surface deposition of NDs with oxygen-containing functional groups on 3D-printed PCL scaffolds increased their hydrophilicity and degradation rate with significant enhancement of thein-vitrocell adhesion compared to untreated PCL scaffolds.