Search

A series of new pyrrole-coupled carboxamide derivatives had been synthesized and amply characterized by various techniques, viz FTIR, 1H-NMR, 13C-NMR, and LCMS. All these compounds had undergone evaluation for their PASS, BBB, pharmacophore model, ADME, and bioactive score. The antibacterial properties of all the derivatives were examined and compound 5i demonstrated strong antibacterial activity against MRSA. A membrane damage investigation supported by SEM pictures, cellular content leakage, potassium efflux, and bacterial respiration suppression showed that compound 5i had anti-MRSA properties. A good binding score of -9.11 was found for compound 5i against the MRSA protein 6FTB in an in silico molecular docking analysis, compared to a score of -10.25 for streptomycin. Based on these findings, compound 5i can be further studied in order to develop it as a drug to treat MRSA infections.

Bimetallic sulfide materials are considered as suitable candidates for improving the oxygen evaluation reaction (OER) performance. Here, CoNi2S4 materials are developed by an effective hydrothermal approach and employing anhydrous Na2S.xH2O as sulfur precursor. Altering the molar concentrations of Co and Ni precursors affects the morphologies, Co, Ni contents, Co3+ and Ni3+ centers. CoNi2S4–1 with lower concentrations possesses higher Co3+, Ni3+ and Co3+/Co2+ ratios boosting the OER performance. In addition, CoNi2S4–1 demonstrates a potential of 1.60 V vs. RHE to generate a 10 mA cm−2 with a lower Tafel slope, better mass activity and stability in an alkaline solution.

In the present work, a new kind of nanocomposite (NC)-based solid component was prepared for formulating nanofluids (NFs). The NC comprised metal oxide (titanium dioxide, TiO2) dispersed in a conducting polymer with polyaniline (PANI) and chemically linked silyl–alkyl units in it (PSA) that were designated as T-PSA NC. The NFs with ethylene glycol (EG) as a base fluid were prepared with T-PSA NCs with various compositions of TiO2 and PSA as well for various concentrations of T-PSA NCs. The scanning electron microscopic evaluation of the NC revealed that PSA deposition on TiO2 nanoparticles (NPs) decreased particle agglomeration. The PSA coating on the TiO2 NPs did not influence the crystalline structure of the TiO2 NPs, according to the X-ray diffraction patterns. The thermophysical characterization and molecular interaction features of the NFs at 303 K including a novel inorganic–organic T-PSA NC, were detailed. Furthermore, the stability of the T-PSA NC-based NFs was investigated experimentally using the zeta potential, and the particle size distribution change was analyzed using the dynamic light scattering (DLS) method. The T-PSA NCs had particle sizes that were significantly bigger than pristine PSA and pure TiO2. Most of the preparation conditions used to produce the T-PSA NCs resulted in moderately stable suspensions in EG. The results revealed that the ultrasonic velocity increased with the increase in the concentration of T-PSA NC mass % in the NFs, the refractive index and thermal conductivity increased with the increase in the concentration, and the surface tension exhibited a linear change when the ratio of mass % concentration of the T-PSA NCs increased. The combined presence of components that synergistically contribute to the electro, thermal, optical, and rheological properties is expected to attract advanced applications for NFs.

The conventional enameling process used in the fabrication of magnet wires requires harmful processes and products. The target of the industry in the actual context of electrification is to increase the electrical machines’ efficiency. Indeed, the electrical insulation systems (EIS) of an electrical machine undergo various environmental constraints that can shorten their lifespans. Consequently, aspects of the insulation need to be improved, such as its thermal resistance. One of the challenges is to implement sustainable technology without losing performance. This work consists of the thermal performance evaluation of new magnet wires insulated by three types of composites of silica-based solution from the Sol–gel process and amorphous polyamide-imide (PAI). These composite coats are overcoated by an extruded thermoplastic resin with and without fillers. Different types of insulation are tested and compared to determine the better configuration. Thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR) analysis, scanning electron microscopy (SEM) analysis, curing characteristics by tangent delta curve, and thermal-aging tests at three temperatures were carried out on the different EIS systems. Dielectric measurements were made between thermal-aging cycles. Their basic mechanical, electrical, and thermal characteristics are promising: the cut-through temperature is situated above 430 °C, their breakdown voltage values are between 5 kV and 9 kV (grade 3), and a good adhesion (overcoming more than 140 turns on a peel test). The thermal-aging results have been consistent with the TGA analysis results. The thermal index following the IEC standards was estimated for the selected EIS, which would have the main basic characteristics of a magnet wire of 200 class; moreover, it would be a greener enameled wire compared to the conventional one.

Clay is a naturally occurring material, and it has been utilized for many industrial processes. In this study, two types of clay namely white clay (WC) and black clay (BC) was used for this investigation. The corrosion performance of the clay samples was carried out using mild steel and galvanized pipes under a buried condition in the field and laboratory exposure studies were carried in the clay extracts. Generally mild steel (MS) and galvanized iron (G.I) are being used as an encasing material for earthing applications. In some places, the soil was enriched with acidic clay, and it causes corrosion of the MS and G.I and it needs periodic replacement of pipes. In this context, a detailed study has been carried out to evaluate the relative corrosion performance of the MS and G.I exposed to the clay environment. Electrochemical corrosion behavior of MS and G.I in clay medium were carried out by using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. The corrosion product formation was characterized by X-Ray Diffraction and Carbon Hydrogen Nitrogen Spectrum analysis. The surface morphology of MS and G.I after the exposure was characterized by Scanning Electron Microscopy (SEM) studies. The results proved that G.I in clay soil was severely affected by corrosion. The reason may be attributed to the insufficient thickness of the zinc coating and the presence of microbes which enhanced the G.I corrosion. Keywords: Clay, Mild steel, Galvanized steel, Corrosion, Electrochemical studies

Bentonite and marconite are the low resistance moisture retaining conductive backfill materials used in earthing applications. Both the products contains some drawbacks: bentonite has limited moisture retaining capacity and marconite has 15–20% impurities which will corrode the earth connections resulting in the loss of the system which are found to be very expensive. Taking into consideration of the above drawbacks, the present study aimed at developing a cost effective and highly conductive backfill material for earthing application with improved performance. For this study, commercially available bentonite and metakaolin (binary) clay was activated through physical, chemical and thermal treatments and the corrosion performance of binary clay was evaluated by using mild steel (MS) and galvanized (GI) steel Among the three activation methods, chemical activation method was found beneficial for mild steel in binary clay media. The conductivity of the chemically activated clay was 204.7 mS/cm, pH was 12.58, and the particle size distribution was found to be 40–50 µm indicates the better corrosion resistance and quite suitable for earthing applications. Chemical activation of the clay mainly involves the breaking of bonds and dissolution of the three-dimensional network structure of glass which in turn cause Na+ ions move closer to the center point of crystal structure and the solubility of SiO2 in clay markedly increases. Potential-time studies showed that galvanizing loses its coating property within ten days in all the three type of clays used. Activation process significantly reduced the corrosion rate (44 and 74 times) in the case of thermally activated (TAC) and chemically activated clay (CAC) respectively. Earth excavation studies were conducted to monitor the corrosion of MS and GI using embedded MnO2 sensor. This investigation opens up a lot of scope for utilizing activated binary clay for all earthing applications. Keywords: Bentonite, Metakaolin, Activated clay, Corrosion studies, Mild steel, Galvanized iron

Composite materials have a wide range of applications in emerging eco-friendly environments. Composites that created from naturally available materials are easily decomposed over time and very cost-effective. Fly ash and sugarcane fiber are widely available waste materials produced on a massive scale. This research was aimed to find an optimal mixture of reinforced composites (fly ash, sugarcane fiber and CNTs) in order to maximize yield strength, ultimate tensile strength and Young’s modulus using a Multi-Objective Evolutionary Algorithm with Decomposition (MOEA/D). Optimizing one objective may have a negative impact on another objective, so the authors used the sophisticated MOEA/D algorithm to simultaneously find optimal values on all three objectives. The Design of Experiments (DOE) method was performed using ANOVA, and then regression equations were generated. The regression equations were optimized using the MOEA/D algorithm to obtain optimal values. Using the optimal compositional values produced by the algorithm, materials were fabricated. The fabricated materials were tested using a Shimadzu UTM machine to cross-validate the findings. A combination of 0.2 wt.% of fly ash, 2 wt.% of SCF, and 0.39 wt.% of CNTs showed a maximum yield strength of 7.52 MPa and Young’s modulus of 1281.18 MPa, with a quite considerable ultimate tensile strength of 10.54 MPa compared with the optimized results obtained through the response surface methodology.

Printable electronics is emerging as one of the fast-growing engineering fields with a higher degree of customization and reliability. Ironically, sustainable printing technology is essential because of the minimal waste to the environment. To move forward, we need to harness the fabrication technology with the potential to support traditional process. In this review, we have systematically discussed in detail the various manufacturing materials and processing technologies. The selection criteria for the assessment are conducted systematically on the manuscript published in the last 10 years (2012–2022) in peer-reviewed journals. We have discussed the various kinds of printable ink which are used for fabrication based on nanoparticles, nanosheets, nanowires, molecular formulation, and resin. The printing methods and technologies used for printing for each technology are also reviewed in detail. Despite the major development in printing technology some critical challenges needed to be addressed and critically assessed. One such challenge is the coffee ring effect, the possible methods to reduce the effect on modulating the ink environmental condition are also indicated. Finally, a summary of printable electronics for various applications across the diverse industrial manufacturing sector is presented.

This work addresses an evolutionary algorithmic approach to reduce the surplus pieces in selective assembly to increase success rates. A novel equal area amidst unequal bin numbers (EAUB) method is proposed for classifying the parts of the ball bearing assembly by considering the various tolerance ranges of parts. The L16 orthogonal array is used for identifying the effectiveness of the proposed EAUB method through varying the number of bins of the parts of an assembly. Because of qualities such as minimal setting parameters, ease of understanding and implementation, and rapid convergence, the moth–flame optimization (MFO) algorithm is put forward in this work for identifying the optimal combination of bins of the parts of an assembly toward maximizing the percentage of the success rate of making assemblies. Computational results showed a 5.78% improvement in the success rate through the proposed approach compared with the past literature. The usage of the MFO algorithm is justified by comparing the computational results with the harmony search algorithm.

Introduction: The infections of wound play an important role in delaying the healing of wound. Moreover, the widespread uses of antibiotics, together with the length of time lead to the emergence of resistant bacterial pathogens contributing to morbidity and mortality. So, there is a need for understanding the distribution of pathogens and the susceptibility pattern of the locality which becomes crucial in the treatment of wound infections. Aim: To determine the frequency and distribution of bacterial isolates and their drug susceptibility pattern isolated from inpatients and outpatients with pus and wound discharge. Materials and Methods: This retrospective study was conducted in the Department of Microbiology at Melmaruvathur Adhiparasakthi Institute of Medical Sciences and Research, Kanchipuram, Tamil Nadu, India, from May 2018 to April 2019. The pus samples were collected from the patients who visited outpatient department and were admitted at In Patient Department (IPD) in the hospital with skin and soft tissue infection. Bacteria were identified by culture and biochemical tests and antibiotic susceptibility test was done by disc diffusion method. Methicillin Resistant Staphylococcus aureus (MRSA) and Extended Spectrum Beta Lactamase (ESBL) in gram negative isolates were detected by cefoxitin disc diffusion method and double disc diffusion method respectively. Results: S.aureus (28.4%) was the most prevalent pathogen followed by P.aeruginosa (20.6%), Proteus (15%), Klebsiella (11.6%), Acinetobacter (8.3%), E.coli (7.6%), Enterococcus sp. (4.8%), S.pyogenes (3.3%). S.aureus and S.pyogenes were sensitive to vancomycin and linezolid. MRSA was found in 61% of isolates and of 61%, 13% of isolates showed inducible clindamycin resistance. Klebsiella, Pseudomonas and Acinetobacter isolates were resistant to multiple antibiotics including third generation cephalosporins. ESBL production was observed in 47% and 31% of Klebsiella and Pseudomonas isolates, respectively. The highest carbapenemase production was found in 21% of Acinetobacter sp. Conclusion: The findings of this study clearly help us to understand the developing resistance percentage among the bacteria causing wound and soft tissue infections and a need for the judicial use of antibiotics, an updated antibiotic policy for the hospital and practice of strict hospital infection control measures.

The main aims in the development of a novel drug delivery vehicle is to efficiently carry therapeutic drugs in the body’s circulatory system and successfully deliver them to the targeted site as needed to safely achieve the desired therapeutic effect. In the present study, a passive targeted functionalised nanocarrier was fabricated or wrapped the hollow mesoporous silica nanoparticles with 3-aminopropyl triethoxysilane (APTES) to prepare APTES-coated hollow mesoporous silica nanoparticles (HMSNAP). A nitrogen sorption analysis confirmed that the shape of hysteresis loops is altered, and subsequently the pore volume and pore diameters of GaC-HMSNAP was reduced by around 56 and 37%, respectively, when compared with HMSNAP. The physico-chemical characterisation studies of fabricated HMSNAP, Ga-HMSNAP and GaC-HMSNAP have confirmed their stability. The drug release capacity of the fabricated Ga-HMSNAP and GaC-HMSNAP for delivery of gallium and curcumin was evaluated in the phosphate buffered saline (pH 3.0, 6.0 and 7.4). In an in silico molecular docking study of the gallium-curcumin complex in PDI, calnexin, HSP60, PDK, caspase 9, Akt1 and PTEN were found to be strong binding. In vitro antitumor activity of both Ga-HMSNAP and GaC-HMSNAP treated MCF-7 cells was investigated in a dose and time-dependent manner. The IC50 values of GaC-HMSNAP (25 µM) were significantly reduced when compared with free gallium concentration (40 µM). The mechanism of gallium-mediated apoptosis was analyzed through western blotting and GaC-HMSNAP has increased caspases 9, 6, cleaved caspase 6, PARP, and GSK 3β(S9) in MCF-7 cells. Similarly, GaC-HMSNAP is reduced mitochondrial proteins such as prohibitin1, HSP60, and SOD1. The phosphorylation of oncogenic proteins such as Akt (S473), c-Raf (S249) PDK1 (S241) and induced cell death in MCF-7 cells. Furthermore, the findings revealed that Ga-HMSNAP and GaC-HMSNAP provide a controlled release of loaded gallium, curcumin and their complex. Altogether, our results depicted that GaC-HMNSAP induced cell death through the mitochondrial intrinsic cell death pathway, which could lead to novel therapeutic strategies for breast adenocarcinoma therapy.

Magnetic nanoparticles (MNPs) are widely used materials for biomedical applications owing to their intriguing chemical, biological and magnetic properties. The evolution of MNP based biomedical applications (such as hyperthermia treatment and drug delivery) could be advanced using magnetic nanofluids (MNFs) designed with a biocompatible surface coating strategy. This study presents the first report on the drug loading/release capability of MNF formulated with methoxy polyethylene glycol (referred to as PEG) coated MNP in aqueous (phosphate buffer) fluid. We have selected MNPs (NiFe2O4, CoFe2O4 and Fe3O4) coated with PEG for MNF formulation and evaluated the loading/release efficacy of doxorubicin (DOX), an anticancer drug. We have presented in detail the drug loading capacity and the time-dependent cumulative drug release of DOX from PEG-coated MNPs based MNFs. Specifically, we have selected three different MNPs (NiFe2O4, CoFe2O4 and Fe3O4) coated with PEG for the MNFs and compared their variance in the loading/release efficacy of DOX, through experimental results fitting into mathematical models. DOX loading takes the order in the MNFs as CoFe2O4 > NiFe2O4 > Fe3O4. Various drug release models were suggested and evaluated for the individual MNP based NFs. While the non-Fickian diffusion (anomalous) model fits for DOX release from PEG coated CoFe2O4, PEG coated NiFe2O4 NF follows zero-order kinetics with a slow drug release rate of 1.33% of DOX per minute. On the other hand, PEG coated NiFe2O4 follows zero-order DOX release. Besides, several thermophysical properties and magnetic susceptibility of the MNFs of different concentrations have been studied by dispersing the MNPs (NiFe2O4, CoFe2O4 and Fe3O4) in the base fluid at 300 K under ultrasonication. This report on the DOX loading/release capability of MNF will set a new paradigm in view that MNF can resolve problems related to the self-heating of drug carriers during mild laser treatment with its thermal conducting properties.

Pyrroloquinone ring systems are important structural units present in many biologically active molecules including a number of marine alkaloids. For example, they are found in a series of marine metabolites, such as tsitsikammamines, zyzzyanones, wakayin, and terreusinone. Several of these alkaloids have exhibited antimicrobial, antimalarial, antifungal, antitumor, and photoprotecting activities. Synthesis of pyrroloquinone unit is the key step in the synthesis of many of these important organic molecules. Here, we present a ceric (IV) ammonium nitrate (CAN) mediated oxidative free radical cyclization reaction of 1,3-dicarbonyl compounds with aminoquinones as a facile methodology for making various substituted pyrroloquinones. 1,3-dicarbonyl compounds used in this study are ethyl acetoacetate, acetylacetone, benzoyl acetone, and N,N-dimethyl acetoacetamide. The aminoquinones used in this study are 2-(benzylamino)naphthalene-1,4-dione and 6-(benzylamino)-1-tosyl-1H-indole-4,7-dione. The yields of the synthesized pyrroloquinones ranged from 23–91%.