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Extraction of eco-friendly biocomposites from eulaliopsis binata: Mechanical, thermal and anti bacterial studies
Get PDFWhen compared to synthetic fibres, natural fibres are more environmentally friendly, biodegradable, and health-promoting. Novel technologies and methods for the growth of new plant fibres are being developed to replace both old conventional natural fibres and synthetic fibres. Eulaliopsis Binata, also known as Sabai Grass, is believed to have a high lignin concentration of upto 18.5 percent and a cellulose content of up to 55 percent. Natural cellulosic fibres were isolated from Eulaliopsis Binata and examined for their properties in this work. Compositional investigations, morphological studies, tensile properties, physical properties, thermal behaviour studies, and anti-bacterial research are all performed on the fibres obtained. The properties of Eulaliopsis Binata fibres were found to be nearly identical to those of conventional fibres, indicating that they could be employed in the production of coarse fibre fabrics, bio-based materials, and automotive interiors
Quantification of an Anti-Rheumatic Agent: Upadacitinib in Biological Fluid (Plasma) By LC- MS/MS
Get PDFAim: Upadacitinib is a Janus kinase/signal transducers and activators of transcription (JAKs) of cytoplasmic tyrosine kinase that has been proven to be effective in treating inflammatory conditions and various immunological diseases/disorders, including rheumatoid arthritis. Tofacitinib and ruxolitinib, which are members of this drug's first generation, did not affect JAK1/JAK3 or JAK1/JAK2 receptors specifically due to a lack of subtype selectivity. As far as we are aware, there is currently no method for the accurate quantification of the anti-rheumatic drug upadacitinib in biological fluid.
Material and Materials: To detect upadacitinib in biological fluid, an unique and reliable LC-MS/MS technique must be developed. Using a symmetric C18 column (150 x 4.6 mm, 3.5 m) and isocratic elution with acetonitrile: water (50:50) as the mobile phase, we created a unique bioanalytical approach here. Formic acid was used to bring the mobile phase's pH down to 4.0, and the flow rate was 1 ml/min. The retention time of the medication was discovered to be 3.12 min, and the total run time was set to 7 min.
Results: With a correlation coefficient (r2) of 0.999, the upadacitinib linearity curve was established at concentrations ranging from 12.5 ng/ml to 100 ng/ml. The theoretical plates, resolution, and tailing factor are system suitability parameters found to be within the acceptable criteria. The recovery studies indicated that the developed method can extract the acceptable % amount of drug 100.3%. The matrix effect study indicates there is no effect of matrix on recovery, the result shown as 104.20% and also other validation parameters like precision, LOD, LOQ are within the acceptable criteria.
Conclusion: The created techniques enable a precise, delicate, and consistent analytical process for the estimation of Upadacitinib in
biological matrix. The stability studies indicate the drug is stable in different accelerated stability study conditions the results are within limits
Multistep synthesis and screening of heterocyclic tetrads containing furan, pyrazoline, thiazole and triazole (or oxadiazole) as antimicrobial and anticancer agents
Get PDFIn the present study novel heterocyclic tetrads containing furan, pyrazoline, thiazole and triazole (or oxadiazole) (1, 2, 3, 4a-e and 5a-e) were designed and synthesized and investigated for their antimicrobial (against selected bacteria and fungi) and anticancer potential. The molecules 4e and 5e containing 4-fluoro phenyl and 4-fluoro benzyl substituents showed promising antimicrobial (antibacterial and antifungal activities with MICs ranging between 0.5 and 8 mg/mL. Compounds 3 exhibited potent anticancer activity with an IC50 value of 0.49 ± 1.45 mM against the human gastric cancer cell line (BGC-823) whereas compound 4e displayed an IC50 value of 0.65 ± 0.53 mM against breast cancer (MCF-7) cell line respectively. All compounds showed selective toxicity against the cancer cell lines compared to human normal liver cell lines. Molecular docking studies of the most potent compounds (3 and 4e) against selected microbial and cancer proteins revealed the crucial binding interactions of the potent compounds with the target enzymes. Compounds 3 and 4e are promising lead molecules to be developed as potential drug candidate
Metal salts used as an efficient catalyst to reduce the ring opening polymerization temperature of benzoxazines
No full textABSTRACT
An attempt was made to develop low-temperature curing aniline-based benzoxazines (BA-a/BF-a) using various transition metal salts, such as FeCl3, CoCl2, NiBr2, CuCl2, ZnCl2, Zn(OAc)2, CdCl2 and Alkali–Alkaline earth metal salts, such as LiCl, KI and CaCl2 and main group metal salt AlCl3 as an efficient catalyst. The findings of the DSC analysis revealed that the main group and transition metal salts had outstanding catalytic activity and were able to reduce the curing temperature of benzoxazines (BA-a/BF-a). Among the various metal salts, FeCl3, AlCl3, ZnCl2 and Zn(OAc)2 exposed excellent catalytic behavior in lowering the curing temperature of benzoxazines to 145 �C (BA-a) and 150 �C (BF-a) from 217 to 218 �C, respectively. The thermal stability and flame retardant char�acteristics of the resultant polybenzoxazines (PBz’s), are also studied and included in this work. In the presence of catalysts, the initial degradation temperature almost same, residual char yield increased from 27 to 55%, and the flame retardant properties increased to 39.5 from 28.5 for the resultant PBz’
A chemodosimeter for selective fluorogenic and chromogenic detection of phenylenediamine isomers
No full textAbstract
A chromogenic and fuorogenic active coumarin-based chemodosimeter (DP21) has been synthesized. The probe shows
remarkable fuorescent intensity with phenylenediamine isomers (PDA) such as ortho-phenylenediamine (OPD) and para�phenylenediamine (PPD) in the presence of competitive species. The probe changes from light yellow to reddish brown and dark yellow with OPD and PPD, respectively, through naked eye. The interaction of lone pair electrons in carbonyl group
present in DP21 with amino group of OPD and PPD shows the intermolecular hydrogen bonding. The PDA isomers can be
detected selectively in the presence of other interfering organic and inorganic amines by the DP21. It shows excellent low
detection limit (LOD) for OPD and PPD is 0.19 nM and 0.4 nM respectively
Evaluation of aluminum to composite bonded lap joints
No full textAdhesive bond is one of the best suitable joining technique for fiber reinforced polymer (FRP) composite structures used in
aerospace applications. The weight of the composite structure greatly reduces by using structural adhesives for the joining
processes. The surface preparation plays a major role for achieving the better bond strength. The present work deals with the validation of the bond strength of single lap joint(SLJ) with dissimilar adherends. The Al adherend has been considered for the surface treatments such as sand paper, NaOH and Resin pre-coating (RPC) for SLJs. The angle of contacts for the different surface treated specimens has been measured using the Young–Laplace method. X-Ray radiography and ultrasonic testing has been carried to verify the internal defects of bonded joint. The bonding strength was evaluated using a tensile and flexural test rig in polymer UTM. The bond strength of the RPC surface treated bonded joints showed better performance in terms of peak load and shear strength. The maximum shear strength has been increased up to 154.63 percentage when compared to untreated surface specimens, similar trend was observed in flexural strength. A numerical simulation model has been developed for validating the results. The comprehensive analysis for the de-bonded joints at maximum loading conditions has been done with morphological studies
Machining Performance of AA2024/5Al2O3/5Gr Hybrid Composites under Al2O3 Mixed Dielectric Medium
No full textIn this research work, AA2024/5Al2O3/5Gr hybrid composites fabricated through stir casting were machined utilising an electric discharge machine (EDM). Experiments were performed by varying current, pulse on time (POT), gap voltage (GV), and Al2O3 powder concentration (PC). .e experiments were designed using response surface methodology in which material removal rate (MRR), tool wear rate (TWR), and surface roughness (Ra) were recorded as responses. .e addition of Al2O3 particles has a
positive impact on MRR and Ra, whereas it has a negative impact on TWR. .e interaction impact of process parameters (p-p) on responses was thoroughly analyzed using contour plots. A mathematical model was developed and validated for all the responses. .e experimental results were compared with the predicted values. It was found that all the values have a maximum deviation of 3.5%. .e ANOVA table reveals that the PC was the most influential factor followed by the curren
Optimization of cardanol oil dielectric-activated EDM process parameters in machining of silicon steel
No full textThe current research uses Taguchi grey relational analysis to optimize the process parameters in micro electro discharge
machining of silicon steel using nickel-coated brass (NCB) tool and waste cashew shell oil-activated water-based dielectric. The key goal of this study was to determine the most infuencing process parameter, which had the greatest impact on
material removal rate (MRR) and tool wear rate (TWR) while drilling silicon steel. Another goal was to optimize the micro
EDM process parameters to achieve high MRR with reduced tool wear rate in coated tools. Using the electroless plating
process, a 0.47 mm brass tool was coated with 0.5, 1.0, and 2 µm nickel; similarly, the dielectric medium was activated using
5, 10, and 15 wt.% of cardanol oil. The method parameters were optimized using an orthogonal array and a grey method.
In the micro EDM drilling method, grey relational analysis was used to evaluate the most afecting parameters, such as gap
voltage, coating thickness, and cardanol oil percentage. Due to the increase in electron transfer, the cardanol oil percentage
was found to be the most infuencing process parameter among others. At second, the gap voltage dominates the machining
process. It is noted that the optimized process parameter was A3B1C3, which had an MRR of 9.69 mm3 /min and a tool wear
rate (TWR) of 1.09 mm3 /min, as well as a grey relational grade of 0.749. Thus, the grey relational grade value of confrmation experiment is increased by 2.04% over the predicted mean value of 0.73
Multiparametric Optimization on Influence of Ethanol and Biodiesel Blends on Nanocoated Engine by Full Factorial Design
No full textEnergy conservation and management have become critical industrial activities, since energy expenses account for a significant portion of production costs. This proactive strategy has had an effect on worldwide energy consumption trends. Integration of thermal barrier coatings into engine design is necessary to solve efficiency concerns, and this coating technology has the potential to increase engine power while lowering specific fuel consumption. In a similar line, biodiesel has been presented as a possible substitute to diesel since it is nontoxic and sourced from renewable energy sources. The present study aims to enhance the performance of a diesel engine via the use of a thermal barrier-coated piston that works on biodiesel mixes. Due to its outstanding thermal insulation qualities, yttria-stabilized zirconia is the preferred material for thermal barrier coatings. Brake thermal efficiency for B20E15 is about 4% better than diesel and for B20E05 and B20E15 is about 4.6% and 13.5% less fuel consumption. CO and HC emissions were reduced by 6% to 8% on average with the B20 blends. Biodiesel blends were compared to pure diesel in terms of performance and emissions, and the blend ratio was improved using a design of experiment tool
OPTIMIZATION OF MACHINING CHARACTERISTICS DURING HELICAL MILLING OF AISI D2 STEEL CONSIDERING CHIP GEOMETRY
No full textHelical milling is one of the high-performance and high-quality hole manufacturing activities with strong prospects for the automotive and aerospace industries. Literature suggests chip
geometry plays a significant role in optimizing machining operations. In the present study, a mechanistic approach is used to estimate the chip geometry, cutting force and power/energy
consumption concerning the tool rotation angle. Experiments are conducted at different levels of spindle rotational speed, cutter orbital speed and axial depth of cuts using 8 and 10 mm
diameter mill cutters. Experimental results for cutting speed in X, Y and Z directions are measured. A hybrid approach, which combines the Taguchi method and Graph theory and
matrix approach (GTMA) technique is used and optimized process parameters. The highest aggregate utility process parameters are met by 2000 rpm spindle speed, 50 rpm orbital speed and 0.2 mm axial cutting depth during helical milling of AISI D2 steel. FEM simulation is used for predicting the chip thickness, cutting forces and power consumption and also validated the optimizatio