Fourier Transform Infrared Radiation Research Articles

Synthesis of AgO/CuO/PVA/starch hydrogel by casting method and characterizations to safely overcome skin infections: A possible application in wound healing as a dressing

Wounds are frequently developing resistance to a conventional wound dressing. Therefore, bioactive and biodegradable hydrogel membranes that could serve as wound dressing could be a legitimate strategy for wound healing, Herein, a chemically cross-linking method was used to synthesize polyvinyl alcohol (PVA)/starch hydrogel, which was subsequently loaded, via the solution casting method, with Silver oxide/Copper oxide (AgO/CuO) nanocomposite (NC) tested at various concentrations (i.e., 0.1, 0.3, 0.5, and 0.7 g/L). The prepared hydrogels were physically characterized through standard techniques, including Dynamic Light Scattering (DLS), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), and Fourier Transform Infrared Radiation (FTIR). The influence of the different AgO/CuO NC concentrations was analyzed through tensile strength, swelling behavior, moisture retention capability (MRC), gel fraction, and water vapor transport (WVT) analyses. The relative toxicity (patch test) of hydrogel membranes was also evaluated on the human skin. The antibacterial potential was investigated against common skin pathogens (i.e., Salmonella typhimurium, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, and Candida albicans) through the disc diffusion method (DDM). SEM images depicted AgO/CuO/PVA/starch hydrogel membranes as shiny, smooth, and dense. XRD analysis revealed the purity and crystallinity of these hydrogels. FTIR data determined the functional chemical groups and confirmed the successful preparation of AgO/CuO/PVA/starch hydrogels. The increased concentrations of AgO/CuO NC in PVA/starch hydrogel membrane has boosted the tensile strength, swelling behavior, and MRC of the hydrogel membranes, whereas the WVT and gel fraction were decreased. Also, the AgO/CuO/PVA/starch hydrogel exerted enhanced antimicrobial activity against all the tested skin pathogens and no toxicity was observed when applied to the human skin. Taken together, the prepared AgO/CuO/PVA/starch hydrogel is a promising approach for wound dressing due to its desirable mechanical properties, safety, and its excellent barrier against skin pathogen penetration and infection.

Development, Characterisation and Biocompatibility Analysis of a Collagen-Gelatin-Hydroxyapatite Scaffold for Guided Bone Regeneration

Guided Bone Regeneration (GBR) is the choice of treatment for improving the horizontal and vertical bone volume through bone grafting. GBR membranes work on the principle of preventing epithelial migration into the defect space while maintaining the space for cell migration and differentiation at the defect site. Hydroxyapatite has been commonly used as a bone graft for infrabony defects. The study was conducted at the Department of Biomaterials at Saveetha Dental College. GBR membrane was prepared and its material characterization was done using Scanning Electron Microscope (SEM), Energy Dispersive X-ray (EDX) analysis, Fourier Transform Infrared Radiation (FTIR), and Confocal Analysis. The developed GBR membrane revealed SEM properties conducive to cell attachment. EDX and FTIR analysis showed the successful development of the collagen-gelatin-hydroxyapatite membrane. Cell culture and confocal analysis revealed excellent biocompatibility with a homogenous layer of viable cells. The developed composite GBR membrane is a biogenic membrane with relevant biomineralization potential that should be applied for GBR applications.

Fe3O4 nanoparticles impregnated eggshell as an efficient biocatalyst for eco-friendly synthesis of 2-amino thiophene derivatives

In this study, a biodegradable and eco-friendly biocatalyst (eggshell/Fe3O4) was synthesized utilizing eggshell impregnated with Fe3O4 nanoparticles. The characterization of prepared catalyst was carried out by Fourier transform infrared radiation (FT-IR), scanning electron microscopy (SEM), X-ray Diffraction (XRD), energy-dispersive X-ray (EDX), thermal gravimetric analysis-differential thermogravimetry (TGA-DTG), vibrating sample magnometer (VSM), and atomic force microscopy (AFM). The eggshell/Fe3O4 biocatalyst was served in multi-component reactions (MCRs) for the synthesis of 2-amino thiophene derivatives from variety aromatic aldehydes, malononitrile, ethyl acetoacetate, and sulfur (S8). To achieve optimal reaction conditions, a thorough examination was conducted on key factors, such as the solvent type, reaction time and temperature, and the ratio of eggshell to Fe3O4. The findings suggest that high yield product can be obtained at microwave temperature (MW) in EtOH solvent within 10 min. Additionally, the eggshell/Fe3O4 biocatalyst exhibited high catalytic activity, which was sustained over the five cycles, without any significant decline in its performance.

A study of surface fatigue wear and influence of contaminated lubricant in journal bearing system using tribological and vibration analyses

In the present work, journal bearing performance was evaluated using condition monitoring processes namely wear debris, vibration signal, lubricant oil degradation and temperature analyses. The journal bearing system was operated at 800 rpm and 200 N constant speed and load over a period of 1200 h. The lubricant oil samples were collected for every 300 h of test duration for oil degradation and wear particle analyses by using Fourier transform infrared radiation (FTIR) and scanning electron microscope/energy dispersive X-ray spectroscopy (SEM/EDS) techniques, respectively. FTIR results provided specific chemical bonds and functional groups contained in the degraded oil. The vibration signals were acquired for every 100 h of operation, and a fast Fourier transform (FFT) frequency spectrum technique was employed for vibration signal analysis. The friction coefficient and specific wear rate parameters were considered to evaluate the tribological performance of the journal-bearing system. Statistical parameters, namely root-mean-square and kurtosis, were evaluated. Wear mechanisms such as abrasive, adhesive and surface fatigue wear were observed on the journal-bearing contact surfaces using a USB optical microscope. The scoring on the bearing element confirmed the fault development and resulted in an increase in vibration amplitudes. Higher mass loss in the bearing material was observed due to high friction and wear rates owing to its being a softer material than that of the journal material. The results obtained from the aforementioned parameter assessment techniques provided a reliable information on the defects which appeared on journal-bearing contact surfaces.

Effects of fiber type, content, orientation, and surface treatments on the mechanical properties of PAFRP composite

In present scenario, natural fibers are the preferred choice of manufactures to fabricate the sustainable polymer matrix composites. These composites may be a good substitute for synthetic materials after achieving the comparable strength with some treatments. Pineapple leaf fiber (PALF) contains high cellulose with low micro fibrillar angle which leads to decent inherent fiber strength. It is used for reinforcement in the proposed work to fabricate the epoxy matrix composite using hand layup method. During testing of composite, the effects of fiber content, type, and orientations on mechanical properties have been examined. Samples were prepared by varying the fiber type (short and long fiber), fiber orientations (at 0°, 90°, and 45°) and fiber contents by weight % (i.e., 5, 10, 15 and 25). The results of mechanical characterization reveal that the tensile and flexural strength for short fiber composite is found maximum at 25% of fiber content (20.85 MPa and 42.70 MPa, respectively). However, long fiber reinforced composite with 5% of fiber content exhibits maximum tensile and flexural strength as: 35.72 MPa and 56.19 MPa. The maximum flexural strength and impact strength of composite were found as 52.98 MPa and 25.30 J m−2, respectively when the fibers are oriented at 0°. The maximum values of water absorption in composite were found as: 1.74% for short fiber and 1.25% for long fiber reinforced composites. The Fourier transform infrared radiation (FTIR) spectroscopy confirms the removal of non-cellulose contents within the composite. Finally, the morphological analysis was carried out to find the debonding, splitting and pull-out of fibers within the composites which are the major reasons of composite failure.

Investigation of Mineral Oil and CuO Mixed Synthetic Oil in Compression Ignition Engines: A Comparison of Physicochemical Attributes

Mineral oil resources are depleting rapidly, and the slower conventional oil biodegradation process results in environmental pollution. To resolve this issue, cupric oxide (CuO) nanoparticles (1% wt) were introduced into a base oil to improve the lubricating capability of castor oil. In addition, 1% wt. sodium dodecyl sulfate was also blended with the base oil in order to attain the maximum dispersion stability of CuO nanoparticles in the castor oil. Afterward, thermophysical property, atomic absorption spectroscopy, and Fourier transform infrared radiation (FTIR) testing of the lubricant oil sample were performed before and after 100 h of engine operations at 75% throttle and 2200 rpm for each lubricant sample in order to check the capability of the novel oil with mineral oil. Compared with the natural mineral oil, the behavior of the CuO-based lubricant has essentially the same physical features, as measured according to ASTM standard methods. The physicochemical properties like (KV)40 °C, (KV)100 °C, FP, ash, and TBN decrease more in the case of the synthetic oil by 1.15, 1.11, 0.46, 1.1, and 1.2% than in the conventional oil, respectively. FTIR testing shows that the maximum peaks lie in the region of 500 to 1750 cm−1, which shows the presence of C=O, C-N, and C-Br to a maximum extent in the lubricant oil sample. AAS testing shows that the synthetic oil has 21.64, 3.23, 21.44, and 1.23% higher chromium, iron, aluminum, and zinc content. However, the copper and calcium content in the synthetic oil is 14.72 and 17.68%, respectively. It can be concluded that novel bio-lubricants can be utilized as an alternative to those applications that are powered by naturally produced mineral oil after adding suitable additives that further enhance their performance.

Influence of heavyweight aggregate on the fresh, mechanical, durability, and microstructural properties of self-compacting concrete under elevated temperatures

Recently, attention has been drawn to the production of heavyweight self-compacting concrete which combines the benefits of heavyweight concrete (HWC) and self-compacting concrete (SCC). This paper investigates the effect of using the barite coarse aggregate (size 4–8 mm) as substitution of volume of the natural coarse aggregate (size 4–8 mm) with various percentages (0, 20, 40, 60, 80, and 100%) on self-compacting concrete (SCC) properties. Slump-flow, T500 time, V-funnel, J-ring, L-box test, and fresh density were used to evaluate the fresh SCC characteristics. However, compressive strength, flexural strength, splitting tensile strength, water absorption, dry density, sulphate attack, and ultrasonic pulse velocity were used to evaluate the mechanical and durability characteristics. In addition, the impact of elevated temperatures (600 °C and 800 °C) on SCC containing various ratios of barite was studied through the evaluation of the density and compressive strength losses. Also, using fourier transform infrared radiation (FTIR) technique, mercury intrusion porosimetry (MIP), and scanning electron microscope (SEM), a microstructural investigation was conducted on hardened SCC containing various ratios of barite to determine the behaviour of barite in comparison to the control mix. The results demonstrate a slight negative effect on fresh and hardened of SCC properties with increasing percentages of barite. However, concrete incorporating up to 80% barite fulfilled all of the EFNARC-recommended criteria for SCC and the dry density of samples containing 80% barite was 2.660 kg/m3. Therefore, the self-compacting and heavyweight concrete characteristics were met by incorporating 80% barite as coarse aggregates. Nevertheless, the rate of increment in compressive strength increased with increasing barite ratios after exposure to 15 cycles of sulphate attack compared to the non-exposed samples.

Characterization Of Carbohydrates-based Root and Tuber Flour Using Fourier Transform Infrared Radiation (FTIR)

Characterization Of Carbohydrates-based Root and Tuber Flour Using Fourier Transform Infrared Radiation (FTIR)

Sulfidation performance of unsupported and SBA 15-supported Ca-based mixed metal oxides

Coal is the most widely used fossil fuel resource, and clean coal technologies allow an increase in the efficiency of clean energy production. Gasification-based combined cycle power generation systems, for example, aim to produce a mixture of CO and H2 (syngas) formed from coal and biomass. However, H2S is an undesired gasification product of fossil fuels with their high sulfur content. Hot gas desulfurization (HGD) reduces the sulfur contents of the gasification products by eliminating thermal losses of endothermic syngas formation processes. This study aims to develop efficient sorbents to remove H2S from hot flue gas. Unsupported and SBA 15-supported Ca-based binary mixed metal oxides (CuO, FeO, MnO, ZnO) were synthesized as sulfur sorbents by the wet impregnation method. The crystal structure of the sorbents was determined by X-ray diffraction (XRD), while BET analysis was used to determine the surface area and pore size distribution of the sorbents. The results of the XRD and BET analyses revealed mixed metal oxide formation and a high surface area of SBA 15-supported sorbents, respectively. Mixed metal oxide formation was also confirmed by Fourier transform infrared radiation (FTIR) spectroscopy. The desulfurization performance of the sorbents was examined by a simulated gas mixture at 800 °C. A gas chromatography analyzer equipped with a flame photometric detector was used to follow the H2S concentration. SBA 15-supported CaO–MnO exhibited the best desulfurization performance at 800 °C with a breakthrough sulfur capacity (BSC) of 43.38 g S/100 g sorbent in the longest breakthrough time of 1077 min.

Evaluation of tribological property and coating reliability of alumina and aluminum silicate-coated A356 aluminum alloy

Material loss due to relative motion between the contact surfaces causes surface degradation leading to premature failure of engineering systems. Of the several techniques to improve the wear resistance of rubbing components, the process of providing a hard protective surface coating has gained tremendous significance. Aluminum alloys used in engineering applications are exposed to rubbing, resulting in progressive wear. Sol-gel coating is a widely accepted surface coating technique for aluminum alloys, and this paper focuses on alumina and aluminum silicate coating applied to aluminum alloys. The tribological characteristics such as coefficient of friction (COF) and volumetric wear losses (VWL) are evaluated using a pin on disc (POD) tribometer. Finite-element analysis (FEA) plays a vital role in bringing an approximate solution to various engineering and non-engineering problems. The POD tribometer is modelled in the design modeller of the Ansys workbench based on the Archard wear model. The coating reliability is experimentally estimated based on its tribological properties. Surface hardness is measured by microhardness indentation test, and materials characterization is done using atomic force microscopy (AFM) and Fourier transform infrared radiation (FTIR) spectroscopy. It is observed that alumina coating exhibits better tribological properties than aluminum silicate-coated A356 aluminum alloy.

Investigation of the effects of deep cryogenic treatment on the structural and mechanic properties of polyoxymethylene copolymer (POM-C) materials

Polyoxymethylene is used as an engineering material in many fields such as aircraft, aviation, and automotive industries in today due to its thermal resistance and mechanical properties. In this study, it is aimed to investigate the effects on the mechanical and structural properties of polyoxymethylene copolymer (POM-C) materials, which are used in many different industrial applications, by applying cryogenic treatment. For this purpose, deep cryogenic treatment was applied to the prepared samples at −175°C for 6, 12, 18, and 24 h, and then tensile, abrasion, impact, and hardness tests were applied to the samples that were kept at room temperature. In order to understand the changes in micro and crystal structures, XRD (X-Ray Diffraction), SEM (Scanning Electron Microscope), and FTIR (Fourier Transform Infrared Radiation) analyzes were performed, and based on these analyzes, the differences in the structure of the POM-C material were compared. It was observed that there was no improvement in the tensile strength of the deep cryogenically treated samples, but an increase in hardness and impact strength was detected.

To study the structural, electrical, and magnetic properties of M (M = Mg2+, Mn2+, and Cd2+) doped Cu-Ni-Co-La spinel ferrites

Tertiary Cu0.25Ni0.15M0.25Co0.35La0.15Fe1.85O4 (M = Mg2+, Mn2+, and Cd2+) spinel ferrites powders were prepared using the cost-effective sol-gel auto combustion route. The lattice parameters, absorption and vibrational bands, energy band gap, AC conductivity, and dielectric loss of the as-prepared ferrites were all measured. The Cd2+ doped ferrite has a minimum crystallite size (D) of 50.9 nm, which is smaller compared to Mg2+ and Mn2+ doped ferrites. Furthermore, the X-ray diffraction (XRD), as well as Fourier transform infrared radiation (FTIR) and Raman analysis confirmed the doping of Mg2+, Mn2+, and Cd2+ ions on their respective lattice sites. The resistivity of the divalent ions (Mg2+, Mn2+, and Cd2+) doped ferrites decreased in the para region and increased in the ferro region as the temperature increased. Moreover, the resistivity of the Cd2+ doped ferrite was smaller when compared to the ferrites doped with Mg2+ and Mn2+ ions. From Arrhenius plots, the minimum activation energy (ΔE) 0.8671 eV was observed for Cd2+ doped ferrites. The Cd2+ substituted ferrite also has the smallest AC conductivity and dielectric loss compared to Mg2+ and Mn2+ substituted ferrites. The coercivity and saturation magnetization were 136.41 Oe and 92.29 emu/g for the Cd2+ doped ferrite, respectively. These results suggest that the Cd2+ doped ferrite material could be used in high-frequency and high-power applications.

Development of nanofibrous membrane from recycled polyethene terephthalate bottle by electrospinning

Recycling polyethene terephthalate (PET) bottles has attracted a lot of attention nowadays due to its polluting nature. Researchers are seeking to recycle the substance to minimize its environmental impact. In order to explore their potential use as facemasks, air conditioners, and automobile's air filtration media, this research looks to develop and characterize electrospun nanofibrous membranes made from recycled PET bottle. Scanning electron microscopy (SEM), Fourier-transform infrared radiation (FTIR), universal tensile testing machine, air permeability tester, moisture management tester (MMT), and particle filtration tester were used to examine the morphological structure, bonding behavior, breaking force, air permeability, moisture management, and efficiency of particle filtration of the developed sample respectively. SEM analysis showed a homogeneous and smooth fiber with an average diameter of 198.5 nm and FTIR analysis confirmed a polyethene terephthalate composition. The maximum strength of the nanofibrous membrane was found to be 20 N corresponding to an elongation value of 4.68 mm. The overall moisture management properties (OMCC) appeared as water repellent fabric which would be be washable, and reusable. The average air permeability of the developed sample was obtained 8.59 L/min. In addition, filtration efficiency appeared 97.04% in particle size 0.3 µm. This nanofibrous membrane would be ideal for air filtration due to its high particle filtration performance, adequate mechanical strength, suitable structure, low toxicity, and reusability.

Evaluation of synthesized inorganic nanomaterials Plumeria alba against Aedes aegypti and in vivo toxicity

Silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) were fabricated using Plumeria alba leaf extracts to control the mosquito Aedes aegypti. Synthesized AgNPs and AuNPs were characterized by ultraviolet-visible spectroscopy, Fourier-Transform Infrared Radiation (FTIR) spectroscopy, X-ray diffraction (XRD), and transmission electron microscope (TEM) analysis. Susceptibility levels of Ae. aegypti mosquito larvae to the plant extract P. alba and its silver nanoparticles (AgNPs) and gold nanoparticles were determined. The AgNPs and AuNPs spectra displayed their maximum absorption at 300 nm and 500 nm, respectively. The larval mortality of AgNPs and AuNPs were highly effective LC50 were 69.9592 ppm and 88.2635 ppm compared to the aqueous leaf extract of P. alba LC50 was 178.4713 ppm. Furthermore, no significant effects of nanoparticle preparations of P. alba extract 10,000 ppm dose up to one week revealed neither toxic signs nor death within seven days of administration. However, there were no apparent signs of delayed toxicity when the rats were observed for an additional seven days. Current studies revealed that the P. alba leaf extract, AgNPs and AuNPs are biologically safe on animals and eco-friendly for control of Aedes aegypti mosquito.

Licorice extract-infused electrospun nanofiber scaffold for wound healing

Recently, nanofibers filled with various kinds of components from herbal extracts have been developed for use in wound healing. In this study, nanofiber scaffolds were developed from different mixing ratios of licorice (Glycyrrhiza glabra) extract and polyvinyl alcohol (PVA) by electrospinning. It was determined that the developed PVA-licorice nanofiber (PLN) scaffold showed outstanding antibacterial efficacy against Staphylococcus aureus (S. aureus), forming a 15 mm inhibitory zone against the bacterial cell. Only a small proportion of cells survived after contact to the substance on the vero cell line, according to in vitro cytotoxicity testing of it. Scanning electron microscopy (SEM), fourier transform infrared radiation (FT-IR), thermogravimetric analysis (TGA), and moisture management tester (MMT) were also used to analyze the morphological structure, compositional analysis, thermal behavior, and moisture management properties of the fabricated scaffolds, respectively. Average fiber diameter and pore size of the developed PLN scaffolds were measured from SEM images. The presence of licorice components in PLN scaffolds were confirmed by FT-IR spectra analysis. According to MMT, the created sample with maximum licorice concentration has better absorption characteristics, suggesting it could be a good candidate for wound healing.

Green Synthesis and Investigation of Surface Effects of α-Fe2O3@TiO2 Nanocomposites by Impedance Spectroscopy.

Nanocomposites based on iron oxide/titanium oxide nanoparticles were prepared by employing green synthesis, which involved phytochemical-mediated reduction using ginger extract. XRD confirmed the composite formation, while scanning electron microscopy (SEM), dynamic light scattering (DLS), and energy-dispersive X-ray spectroscopy (EDX) was employed to investigate the particle size, particle morphology, and elemental analysis. SEM indicated the formation of particles with non-uniform shape and size distribution, while EDX confirmed the presence of Fe, Ti and oxygen in their elemental state. The surface effects were investigated by Fourier transform infrared radiation (FTIR) and impedance spectroscopy (IS) at room temperature. IS confirmed the co-existence of grains and grain boundaries. Thus, FTIR and IS analysis helped establish a correlation between enhanced surface activity and the synthesis route adopted. It was established that the surface activity was sensitive to the synthesis route adopted. The sample density, variation in grain size, and electrical resistivity were linked with surface defects, and these defects were related to temperature. The disorder and defects created trap centers at the sample’s surface, leading to adsorption of CO2 from the environment.

Design of data feature-driven 1D/2D convolutional neural networks classifier for recycling black plastic wastes through laser spectroscopy

In this study, two types of convolutional neural network (CNN) classifiers are designed to handle the problem of classifying black plastic wastes. In particular, the black plastic wastes have the property of absorbing laser light coming from spectrometer. Therefore, the classification of black plastic wastes remains still a challenging problem compared to classifying other colored plastic wastes using existing spectroscopy (i.e., NIR). When it comes the classification problem of black plastic wastes, effective classification techniques by the laser spectroscopy of Fourier Transform-Infrared Radiation (FT-IR) with Attenuated Total Reflectance (ATR) and Raman to analyze the classification problem of black plastic wastes are introduced. Due to the strong ability of extracting spatial features and remarkable performance in image classification, 1D and 2D CNN through data features are designed as classifiers. The technique of chemical peak points selection is considered to reduce data redundancy. Furthermore, through the selection of data features based on the extracted 1D data with peak points is introduced. Experimental results demonstrate that 2DCNN classifier designed with the help of 2D data feature selection as well as 1DCNN classifier shows the best performance compared with other reported methods for classifying black plastic wastes.

“Sustainable self-compacting concrete containing waste ceramic tile aggregates: Fresh, mechanical, durability, and microstructural properties”

In construction industry, the use of ceramic materials is rising continuously in the form of sanitary fittings, ceramic tiles, and electrical insulators etc. The ceramic manufacturing industry necessarily generates wastes, categorical of the newly introduced developments in manufacturing processes. During processing, fixing and transportation, the brittle nature of ceramic materials adds to the waste generation in large amounts. Use of all this waste in making of self-compacting concrete (SCC) can help with waste management along with improving the properties of SCC. Hence, in this study, fresh properties, mechanical strength, durability and microstructure of SCC containing waste ceramic tile (WCT) were examined. Six SCC mixes were prepared using crushed WCT as a substitution of natural river sand (NRS). The use of waste ceramic tile as a partial and full substitution (0%, 20%, 40%, 60%, 80% and 100%) of NRS of SCC was examined. The fresh SCC properties tests performed were Slump-flow, T500 time, V-funnel, U- box, J-ring and L-box test, while the mechanical and durability properties were assessed by compressive strength, flexural strength, split tensile strength, water absorption, water permeability and ultrasonic pulse velocity tests. The fresh properties of all mixes were found within limits prescribed by EFNARC. The integration of WCT in SCC mixtures found increase in the compressive, flexural and split tensile strength at 60% substitution and further substitution led to reduction in all strength of SCC. The superior ultrasonic pulse velocity values and higher impermeability characteristics of waste ceramic based SCC mixtures were found till 100% incorporation of WCT, when compared to the reference SCC mix. The microstructural study using Fourier transform infrared radiation (FTIR) technique, X-ray diffraction (XRD), Scanning Electron Microscope (SEM) was performed on hardened SCC to know in depth behavior of waste ceramic over control mix.

Physicochemical Characteristics and Antidiabetic Properties of the Polysaccharides from Pseudostellaria heterophylla.

This study aimed to investigate the Pseudostellaria heterophylla polysaccharides (PF40) physicochemical and antidiabetic characteristics. The ultraviolet–visible (UV) spectra, Fourier transform infrared radiation (FT-IR) spectra, nuclear magnetic resonance (NMR) spectra, zeta potential, surface characteristics, and conformational and thermal stability properties of PF40 were characterized. X-ray diffraction (XRD) and scanning electron microscopy (SEM), combined with Congo red test, revealed that PF40 powder has mainly existed in amorphous form with triple-helix conformation. The single-molecular structure of PF40 exhibited a multi-branched structure extending from the center to the periphery by scanning probe microscopy (SPM) scanning. The monosaccharide residue of PF40 was an α-pyranoid ring and exhibits good stability below 168 °C. Experimental studies on antidiabetic characteristics found that PF40 could significantly improve STZ-induced intestinal mucosal damage and reduce the apoptosis of villus epithelial cells. PF40 combined with metformin could significantly improve the symptoms of insulin resistance in type 2 diabetes mellitus (T2DM) rats, the molecular mechanism might be through inhibiting the expression of RORγ protein and increasing Foxp3 protein in the jejunum of T2DM rats, and then restoring the STZ-induced imbalance of T helper 17(Th17)/ regulatory T cells (Treg) cells, thereby maintaining intestinal immune homeostasis. Results identified in this study provided important information regarding the structure and antidiabetic characteristics of Pseudostellaria heterophylla polysaccharides, which can contribute to the development of Pseudostellaria heterophylla polysaccharides for industrial purposes in the future.

Adsorption of Bemacid Red by Poly Tetra (Ethylene Glycol) Dimethacrylate Crosslinked with 2-Hydroxypropyl Methacrylate Hydrogels: Equilibrium and Kinetic Studies

Besides others, textile industries are the primary sources of discharging a massive amount of highly colored wastewater. Adsorption can be considered the most economically favorable technology method for removing dyes from wastewater. This paper reports the synthesis of Poly tetra (ethyleneglycol) dimethacrylate crosslinked with 2-hydroxypropyl methacrylate (Poly (TtEGDMA-cross-2-HPMA)) hydrogelsand its application as a novel sorbent to remove bemacid red (ET2) dye from aqueous solution under various operating conditions. The equilibrium adsorption capacity was found 142.82–883.60 mg ET2 g–1 of 1% TtEGDMA. The adsorbent was characterized using Fourier transform infrared radiation (FTIR) and 13carbon solid-state nuclear magnetic resonance spectra (13C-NMR). The effects of the experimental parameters include dye concentration and crosslinked agent concentration. The kinetic sorption uptake for ET2 by Poly (TtEGDMA-cross-2-HPMA) at various initial dye concentrations was analyzed by pseudo-first and pseudo-second models. Two sorption isotherms, namely the Langmuir and Freundlich isotherms, were applied to the sorption equilibrium data. The sorption kinetics of ET2 onto the hydrogels followed the pseudo-second-order kinetics model (R2 = 0.999) and the adsorption equilibrium data obeyed the Langmuir isotherm model (R2 = 0.999). It can be concluded that Poly (TtEGDMA-cross-2-HPMA) is an alternative economic sorbent to more costly adsorbents used for dye removal in wastewater treatment processes.