Digital Eprints Services at Vignan's Foundation for Science, Technology & Research
Not a member yet
721 research outputs found
Sort by
Effective Detection of Phenylalanine Using Pyridine Based Sensor
No full textAbstract
Pyridine based organic molecule as probe has been synthesized for the detection of phenylalanine (PA) biomarker. The syn�thesized probe is characterized by 1 H and 13C NMR and mass spectroscopic studies. The photophysical properties for the probe has recorded by colorimetric and fuorimetric techniques. The quenching has been observed between the probe and PA through ICT (Intermolecular Charge Transfer Mechanism). Under optimized conditions, the probe detects PA selectively in the presence of other biologically important biomolecules. The practical application for PA has been successfully applied in human blood serum and urin
Investigation of Mechanical and Physical Behaviours of Polyester Resin Matrix from Recycled Polyethylene Terephthalate with Bamboo Fibre
No full textIn this research article, we investigate the physical and mechanical properties of composites comprised of unsaturated polyester resin (UPR) and recycled polyethylene terephthalate (PET) with 10% to 40% volume of bamboo fibre (BF). Chemical evaluation of BF revealed that BF has a cellulose content of 49.86%, hemicellulose content of 25.17%, and lignin content of 7.14%. As the UPR’s different connections, FTIR identified an interconnecting framework between the styrene monomer (ST) and the unsaturated polyester (UP). It was found by TGA-DTG that there were two breakdown phases. UPR’s physical and mechanical properties were found to be affected by increasing the amount of fibre in the material, with the water absorption rising from 0.7% to 2.81% and the density (1214.38 to 1168.83 kg/m), flexural strength (51.81 to 28.92 MPa), flexural modulus (2.78 to 2.83 GPa), and tensile strength (9.71 to 3.86 MPa) all decreasing at the same time. On the other hand, the hardness increased from 82.4 Shore D to 67.9 Shore D. Fibre distribution flaws in the UPR were found, affecting the composites’ mechanical characteristics. By repurposing two waste
products, this study helps create new materials that are better for the surrounding
PREDICTION AND OPTIMIZATION OF BINARY AND TERNARY ISO-STOICHIOMETRIC GEM BLENDS ON PERFORMANCE AND EMISSSION CHARACTERISTICS OF SI ENGINE USING ANN AND RSM
No full textThe present work aimed at optimizing the performance and emission characteristics of a Port Fuel Injection (PFI) SI engine
fueled with Gasoline-Ethanol-Methanol (GEM) blends using Response Surface Methodology (RSM). Test fuels used in the
study are pure gasoline (E0), E10, E10 equivalent iso-stoichiometric GEM blend (E10_Eq), E20, E20 equivalent isostoichiometric GEM blend (E20_Eq). Formulated E10 and E20 equivalent blends have identical air-fuel ratios, lower heating
values, density, and octane number as target binary blends (E10, E20). The test engine was operated with different fuel blends
by varying the engine speed from 1700 to 3300 rpm at a constant engine load of 5 kg. For optimization of the engine, speed
and fuel blends were considered as input parameters and brake thermal efficiency (B_The), brake specific fuel consumption
(BSFC) and, nitrogen oxide (NOx) emissions as responses. Optimization was carried out using the desirability approach with a target of maximizing the B_The and minimizing the BSFC and NOx. From the results, it was observed that the E10_Eq GEM
blend operation of the test engine has optimized values of B_The, BSFC, and NOx emissions with values of 33.17%, 251
g/kW-hr, and 1389.8 ppm respectively at an engine speed of 2416 rpm. A composite desirability value of 0.64 obtained from
the regression model shows that RSM can be conveniently employed to determine the significant factors that could impact
engine performance and emissions
Availability Estimation and Maintenance Optimization for Transportations systems
No full textThe system performance depends on the availability, efficiency of maintenance and operating conditions. The industrial systems are designed, manufactured and tested/simulated under laboratory/ideal conditions. But the conditions in
which the systems are working in real-time ndustries/companies are different. Due to this, the components of each system
will fail well before the schedule given by the company even though the periodic maintenance is carried out as per the
manufacturer's standard operating procedures (SOP). The complexity of the system will increase the failure probability and
these failures will affect the performance of the system. Therefore, it is important to know the critical components of the
system. In this paper, a methodology has been applied to identify the bottlenecks in the fleet as the availability estimation. Optimum maintenance intervals are calculated for each variety of systems based on the minimization of downtime.
The presented methodology is applied to on-road vehicles in Andhra Pradesh State Road Transport Corporation
(APSRTC) as a case study. The transmission subsystem is identifiedas a bottleneck in transportation vehicles, availabilities and optimum maintenance intervals areestimated for TVG SML SL and EXP type buse
A Nonconvex Constrained based Optimal Load Scheduling of Generators with Multiple Fuels using meta-heuristic Algorithms
No full textThe primary goal of any electric power generation system is to provide a sufficient amount of electricity to consumers without jeopardizing the system's economic viability. The modernization of the power grid has resulted in a significant rise in power demand, which has increased the cost of producing electrical energy. When the cost of output rises, so does the cost of transferring energy to the end consumer. As a result, the output of energy at various stages of a power system must be optimized. As a result, the cost per unit of thermal energy output is reduced while load demand requirements and transmission lsses are maintained. These complex non-linear quadratic functions with Multiple Fuels lead to a non-Convex problem for steam thermal generating systems, according to previous studies. Perfect Economic Load Dispatch (ELD) modelling for steam thermal generating units is possible with multiple fuels. Because acute variations and disruptions in the incremental cost function are possible, it is difficult to simplify the non-convex problem using existing techniques. Oppositional Teaching Learning Based Optimization (OTLBO) is used to address the ELD problem in this research. Under various load demands, the proposed solution was applied to a 6-unit test system, a 10-unit test system, and a 14-unit test system, and the results were evaluated using the Teaching Learning Based Optimization (TLBO) algorith
Lamotrigine Novel Cocrystals: An Attempt To Enhance Physicochemical Parameters
Get PDFBackground: Cocrystals are defined as multiple component structures whose components interact through non-covalent interactions. Cocrystals can enhance other essential properties of the APIs.
Aim: The current research work focuses on formulating and evaluating novel co-crystals of Lamotrigine anti-epileptic drug (BCS-II)
Methods: The Cocrystals of Lamotrigine drug with different cocrystals formers like Saccharin sodium, 4-Hydroxy benzoic acid, and Methyl paraben used with molar ratios (1:1) were prepared by solvent drop method, co-grinding method, and solvent evaporation method.
Results: The results signify the establishment of intermolecular interaction within the cocrystals. In the novel cocrystals, Lamotrigine was determined to be engaged in the hydrogen bond interaction with the complementary functional groups of Saccharin sodium, 4-Hydroxy benzoic acid, and methyl paraben. Compared with the pure Lamotrigine flow properties for prepared co-crystal by using solvent evaporation method crystals are showing excellent flow properties. LTG-SAC CF I, LTG-HBA I, and LTG-MP III showed 49.6 folds, 7.4 folds, and 3.36 folds improved solubility respectively. The dissolution test showed that the LTG-SAC CF I, LTG-HBA I, and LTG-MP III cocrystals exhibited a 1.09-fold, 1.08-fold, and 1.07-fold higher dissolution rate than the pure Lamotrigine.
Conclusions: LTG-SAC CF I, LTG-HBA I, and LTG-MP III cocrystals showed modification in the chemical environment, intermolecular interactions were established, improved flow properties with enhanced intrinsic solubility and in-vitro dissolution rate than pure drug
Optimization of Ultrasonic Vibration assisted Friction stir process to improve mechanical properties of AA7075-nano B4C surface composite
No full textUltrasonic Vibration assisted Friction Stir Processing is one of the advanced surface modification techniques developed for
ductile materials like aluminium to improve their surface properties. The present study is aimed to improve mechanical
properties of the AA7075-T651 surface composite by reinforcing the nano B4C particles with optimum working condition.
Experiments are conducted at different levels of tool rotation speed, tool processing speed and volume percentage of nano
B4C particles with and without ultrasonic vibrations and the experimental results for ultimate tensile strength, impact
strength, yield strength, percentage of elongation and hardness are measured. Jaya Algorithm (JA) is used and found best
optimum condition such as 1112 r/min of tool rotational speed, 43.96 mm/min of tool traverse speed and 4.02 vol % of B4C
nano particles. Mechanical properties and microstructure are investigated using optical Microscope, Field emission scanning
electron microscope and Transmission electron microscopy analysis. A fine grain structure and uniform distribution of
reinforcement are found in the matrix with the ultrasonic vibrations and the mechanical properties of the AA7075 alloy are
improved. The microstructure of the surface composite is correlated with the mechanical propertie
Experimental and optimization studies of ultrasonic‑assisted friction stir weldments of AA2014‑T651 using graph theory
No full textJoining of Al-Cu based alloys such as AA2014-T651 is very difficult by fusion welding techniques due to liquefaction and solidification cracks. Therefore, solid state welding namely Friction Stir Welding (FSW) is most suitable to join these alloys. The main objective of this work is to identify the most influenced process parameters such as rotation speed of the tool, and tool traverse speed and their levels for fabricating the
weldments by FSW process with using ultrasonic vibrations (UAFSW). A set of experiments were carried out using the plain cylindrical and taper threaded cylindrical tool pin profile at different levels of process parameters and experimental results were collected. A graph theory and utility concept was proposed and found an optimal working condition for better weldment properties. The UAFSW process enhanced the AA2014-
T651 weldment mechanical characteristics at 1100 rev/min of tool rotation speed, and 40 mm/min of tool traverse speed. The tensile strength, yield strength, percentage of elongation, impact strength and micro hardness were found to be 431.69 MPa, 307.47 MPa, 11.66 %, 8.32 J, and 139 HV respectively at optimal working condition. The weld joint obtained using a taper threaded tool pin profiled with ultrasonic vibration exhibits 95% joint efficiency compared to the weldments made by plain cylindrical taper tool pin profile with ultrasonic vibration. The measured characteristics have been correlated with microstructure and fracture features. The optimized responses were verified by the validation test
Investigation on the role of microstructure and temperature on tribological characteristics of fine grained ZE41 Mg alloy
No full textgrain refinement. In addition to grain refinement, decreased intermetallic phase (MgZn) was also observed after FSP. Increased micro-hardness was observed for the processed ZE41 Mg alloy compared to the unprocessed base alloy. X-ray diffraction (XRD) studies demonstrated the texture characteristics in FSPed ZE41. Reciprocating wear studies conducted at three different temperatures, i.e. room temperature, 125 °C, and 250 °C showed lower mass loss
for the processed alloy compared to that of the base alloy, particularly at elevated temperatures. This behavior can be understood by considering the benefit gained from the
smaller grains and decreased amount of intermetallic phase in the processed alloy, which reduced the abrasion wear. Hence, the present study suggests that the grain refinement
and decreased MgZn phase significantly improve the temperature-dependent tribological characteristics of ZE41 Mg allo
Machine Learning-Based Modelling and Predictive Maintenance of Turning Operation under Cooling/Lubrication for Manufacturing Systems
Get PDFIt is proved and examined in this research paper that the perturb and observe (P and O) technique for isolating the photovoltaic
array (PVA) from the power structure may be used to isolate the PV array from the power structure. A single specied voltage
setup can remove the maximum power from a PV cell because of the nonlinear properties of the PV cell’s output. As a result, in
PVA, the maximum power point tracking (MPPT) algorithm is utilized to increase the yield control range by increasing the
maximum power point. In this study, the MPPT computations are carried out with the assistance of a DC-DC boost converter for usage in applications needing high voltage gain at a variety of sun-positioned irradiances and cell temperatures, as demonstrated in the literatur