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Performance of diesel engine enhanced by employing 150µM to 170µM thick plasma sprayed 8YSZ nano grained coating on piston head /
Patent Number: 202241033004, Applicant: S Gowtham Sanjai.
This invention discloses the favorable influence of nano ceramic coated components on the performance of diesel engines. 150 microns thick yttria stabilized zirconia coatings, with nano grained microstructure, when applied by using Atmospheric Plasma Spray (APS) coating technique, on the piston crown of a 5HP, single cylinder diesel engine, reduces the brake specific fuel consumption (BSFC) of the engine by ~ 20%. The improvement in performance has been established by comparing the performances (measuring the BSFC) of the engine when mounted with (a) OEM Piston and thereafter (b) coated piston. -
Bio-derived fuels as diesel fuel and gasoline blend components /
Patent Number: 202241032675, Applicant: Kiran K.
To maximize the effectiveness of a refinery's diesel output, a model for the planning of refinery diesel streams is being created. To determine blending parameters with more accuracy than is possible with typical linear models, nonlinear blending models are utilized. Because there are so many equations and variables involved, it may yield an infeasible solution if the beginning points that have been provided are not enough. -
GPR based subsurface geotechnical exploration
The Seismic refraction technique (SRT) and Electrical resistivity technique (ERT) have long been in use in geotechnical exploration. A relatively recent technique is Ground penetrating radar (GPR). The study presented in this paper is on GPR-aided geotechnical subsurface exploration. The usual method of exploration is drilling, which gives much-needed site-specific information, but is expensive and restricted to a few point locations. The possibilities of non-invasive investigation offered by GPR make it useful for supplementing geotechnical investigations. The present work describes GPR survey at a construction site in Mumbai. The objective was to derive subsurface logs from GPR signals. Conventionally, subsurface logging is done using boreholes. First, the extracted soil and rock samples are examined visually. Second, additional information such as Core recovery ratios (CRR), Rock quality designation (RQD) and Standard penetration test (SPT) N values are collected and strata are demarcated. In comparison, the amplitude variations of GPR signals may not correspond directly to variations of these physical properties with depth. However, the study shows that fairly good correlations do exist with the subsurface stratification and transformed signals. -
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A Theoretical Study of Rayleigh-Benard Convection Problem with Realistic and Artificial Boundary Conditions
In this thesis we present linear and weakly non-linear study of Rayleigh Bard newlineconvection subject to general boundary condition, which includes both physically newlinerealistic and artifcial boundaries. A horizontal confguration is adopted, wherein newlinethe horizontal surfaces are attached to porous blocks, which allows for the inclusion newlineof rough boundaries modelled by the Robin boundary condition on velocity. The Robin boundary condition is utilised to model boundary condition on temperature as well. Adding nanoparticles to a base and#64258;uid results in an increased thermal conductivity of the base and#64258;uid. The objective of this research is to present a conducive understanding of the eand#64256;ect of nanoparticles and its enhanced thermophysical properties eand#64256;ects on the onset of convection. Eand#64256;ects of Rough Boundaries on Rayleigh-Bard Convection in Nanoand#64258;uids A linear and weakly non-linear stability analysis of Rayleigh-Bard convection in a Newtonian nanoand#64258;uid between two rough boundaries is carried out. A newlinesingle-phase description of nanoand#64258;uids is adopted in the study. Water-alumina and newlinewater-copper are nanoand#64258;uids in consideration for the study. The values of thermophysical quantities of nanoand#64258;uids are obtained using either the mixture theory or phenomenological laws. The boundary eigenvalue problem arising in the study is solved using the Maclaurin series. Also, a single-term Galerkin technique is adopted to obtain the guess value of the Rayleigh number and the wave number. Further, improved values of the Rayleigh number and the wave number are obtained using the Newton-Raphson method. The minimal Fourier series representation is used to arrive at the generalised Lorenz model. A detailed discussion is made on the eand#64256;ect newlineof rough boundaries on the onset of convection in nanoand#64258;uids. The study aims to newlinepresent a theoretical comparison between the results of the two nanoand#64258;uids considered and the destabilizing eand#64256;ect showcased by each of the nanoparticles on the onset of convection. -
Classification Framework for Fraud Detection Using Hidden Markov Model
Machine learning is described as a computer program that learns from experience E with regard to some task T and some performance measure P, if its performance on T improves with E as measured by P. Suppose we have a credit card fraud detection which watches which transactions we mark as fraud or not, and on the basis, it knows how to filter better fraudulent transactions then, E is watching your transactions is fraud or not, T is classifying your transactions as fraud or not, P is number of transactions correctly differentiated as spam or not spam. Machine learning has two types: supervised learning and unsupervised learning. Supervised learning is the type of machine learning where machine is provided with input mapped with its output, and these inputs and outputs are used to make a machine learn a particular function from the trained dataset. There are two branches of supervised learning, i.e., classification and regression. In unsupervised learning, we do not supervise model instead we allow machine to work on its own to discover information. Clustering is type of unsupervised learning. 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. -
Enhancement of tensile strength and elastic modulus using bio-waste based carbon nanospheres doped polymer nanocomposites
The Carbon Nano Spheres (CNS) derived from areca nuts were synthesized from pyrolysis process and were used as fillers for fabrication of polymer nano composite materials. The filler materials are loaded in 0.05%, 0.1% and 0.5% loading percentages. The optimum sample was subjected to heat treatment. The tensile strength, elastic modulus and % of elongation were investigated for all samples. The Scanning Electron Microscope (SEM) images revealed the morphological features of optimum samples and hence the uniform dispersion of CNS in polymer matrix. The 0.1% samples showed 10% improvement in Ultimate Tensile Strength (UTS) and 24% improvement in Elastic modulus compared to bare epoxy material. When 0.1% samplewas subjected to heat treatment under 200C the UTS improved by 23%. Hence, CNS reinforced composite materials exhibited unique properties like high strength, less weight and low cost making them suitable for various structural applications such as aerospace, automotive, construction, and electronics industries. The Polymer Society, Taipei 2024. -
Biogenic synthesis of Pd-nanoparticles using Areca Nut Husk Extract: a greener approach to access ?-keto imides and stilbenes
An eco-friendly green method for a one-step synthesis of palladium nanoparticles and their synthetic utility are reported. Phytochemicals like amines, alcohols, and phenols present in the Areca Nut Husk extract facilitate the reduction of Pd(ii) to Pd(0). The phytochemicals serve as stabilising agents and ligands for palladium reduction and the need for an external ligand is avoided. The Field Emission Scanning Electron Microscopy and Transmission Electron Microscopy of newly synthesized palladium nanoparticles revealed a spherical morphology. The catalytic activity of the nanoparticles was tested for 1,2-difunctionalization of ynamides, Heck coupling, denitrogenative coupling of phenylhydrazine and C-H arylation of indole. Moreover, catalyst recyclability, control experiments, mechanistic elucidation, and gram-scale synthesis are elaborated. The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2021. -
Navigating green synthesized metal-based nanoparticles as anti-inflammatory agent Comprehensive review
The biosynthesis of nanomaterials is a vast and expanding field of study due to their applications in a variety of fields, particularly the pharmaceutical and biomedical fields. Various synthetic routes, including physical and chemical methods, have been developed in order to generate metal nanoparticles (NPs) with definite shapes and sizes. In this review, focused on the recent advancements in the green synthetic methods for the generation of silver, zinc and copper NPs with simple and eco-friendly approaches and the potential of the biosynthesized metal and metal oxide NPs as alternative and therapeutic agent for the treatment of inflammatory diseases. Inflammation is a body's own defense mechanism that can become chronic inflammation affecting healthy cells. Owning to the size-based advantages of NPs which can mitigate in theses medical conditions and serve as anti-inflammatory drugs. The factors influencing their physicochemical properties, toxicity, biocompatibility and mode of action to formulate an effective nanomedicine in the treatment of inflammation. 2024 Elsevier B.V. -
Titanium based dual behavioral magnetic nanocomposite for ipso-hydroxylation and selective oxidation reactions under white light
A new titanium-based magnetic nanocomposite was prepared using facile method. The characterization of the prepared nanocomposite by various analytical techniques confirmed the successful coating of TiO2 on to the magnetic surface. A vital role of the prepared nanocomposite as photocatalyst for the selective oxidation of benzyl alcohols to their corresponding aldehydes and ipso-hydroxylation of aryl boronic acids under the illumination of tailor-made set up employing white light was demonstrated. The nanocatalyst was recycled and it retained excellent catalytic activity towards both the reactions upto several cycles demonstrating the excellent heterogeneous nature and possible application in the industries ensuring the sustainability. 2024 Elsevier B.V. -
Magnetically retractable tea extract stabilized palladium nanoparticles for denitrogenative cross-coupling of aryl bromides with arylhydrazines under green conditions: An alternate route for the biaryls synthesis
Novel palladium based magnetic nanocatalyst was synthesized by the co-precipitation method and coated with silica and tea extract as stabilizing agent. Palladation onto the prepared nanocomposite was done to get ION-SiO2/TE-Pd(0) catalyst. Our study is one of the limited number of studies reported for the catalytic denitrogenative coupling of arylbromide and arylhydrazine. This led to the construction of important substituted biaryls bearing various substituents with 8292% yields. The synthesized nanocatalyst was characterized using structural and morphological characterization techniques. It was also observed that only 2 mol% of ION-SiO2/TE-Pd(0) catalyst was sufficient for the catalysis and reusable upto six cycles. 2024 The Authors -
Furaldehyde-based magnetic supported palladium nanoparticles as an efficient heterogeneous catalyst for Mizoroki-Heck cross-coupling reaction
A novel palladium functionalised magnetic nanocatalyst (Fe3O4@SiO2-FA-Pd) was prepared using silica-coated iron oxide and furaldehyde Schiff base as a supported material. FT-IR, VSM, TEM, FESEM, XPS, EDAX and TGA were used to analyse the morphological structure and chemical composition of Fe3O4@SiO2-FA-Pd NPs. Thus, the prepared Fe3O4@SiO2-FA-Pd NPs as a magnetic nanocatalyst were used in the Mizoroki-Heck reaction of arylbromide and terminal alkenes, exhibiting effective catalysis with good yields. The magnetic nanocatalyst can be reused up to 6 times without significantly losing catalytic activity and is easily separable from the reaction mixture. This new catalytic system has significant and potentially useful applications in the pharmaceutical industry. 2024 The Royal Society of Chemistry. -
Palladium immobilized on guanidine functionalized magnetic nanoparticles: a highly effective and recoverable catalyst for ultrasound aided Suzuki-Miyaura cross-coupling reactions
We designed and prepared a palladium catalyst that can be magnetically recyclable by anchoring guanidine moiety on the surface of Fe3O4 nanoparticles, named Fe3O4@SiO2-TCT-Gua-Pd. It was established to be a potent catalyst for the Suzuki-Miyaura cross-coupling reaction (SMCR) in the EtOH/H2O system under ultrasonic conditions. FT-IR spectroscopy, field-emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) microanalysis, vibration sample magnetometry (VSM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and inductively coupled plasma atomic emission spectrometry (ICP-AES) analyses were used to characterize the structure of the Fe3O4@SiO2-TCT-Gua-Pd nanoctalyst. The Fe3O4@SiO2-TCT-Gua-Pd catalyst produced favorable coupled products with excellent yields and was harmonious with various aryl halides and aryl boronic acids. The stability, low palladium leaching, and heterogeneous nature of the nanocatalyst were confirmed by a hot-filtration test. The palladium nanocatalyst could be easily recovered by magnetic field separation and recycled at least 6 times in a row without noticeable loss in its catalytic activity. 2023 The Royal Society of Chemistry. -
Nano-architectured polypyrrole based magnetic nanocatalyst for the N- arylation of imidazoles and fused imidazoles
A new magnetically recoverable polypyrrole supported copper based nanocatalyst was synthesized, characterized with various analytical techniques like Fourier-transform infrared spectroscopy (FTIR), Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray analysis (EDX), High Resolution Transmission Electron Microscopy (HRTEM), Thermogravimetric analysis (TGA), Vibrating Sample Magnetometry (VSM), and Inductively coupled plasma atomic emission spectroscopy (ICP-AES) analysis. The loading of copper on the surface of the catalyst was found to be 4.23 wt%. The application of the synthesized nanocatalyst was checked for the N-arylation of imidazoles. Excellent catalytic performance was obtained with easy recoverability and reusability upto six cycles. The current green protocol makes it environmentally beneficial for scale-up industries. 2025 Elsevier B.V. -
ANALYSING THE SAFETY OF A CAMPUS USING SPATIAL SYNTAX
Everybody has been in campus environments and academic buildings at some point in their lives. The layout of these structures is crucial because it influences how a person behaves and presents themselves. The use of space syntax enables us to examine how individuals behave in relation to their surroundings and how places are used. The nature of the space and the way people move through it have improved because of the application of space syntax in campus planning.A primary concern is safety, this paper is devoted to comprehending how various user groups navigate across a university. Here, we'll be looking at how students move around and behave in relation to how safe they feel on campus. Each user group's paths, nodes and gathering places will be recorded and we'll confirm both the original puiposes and the current uses of the spaces. Additionally, several maps will be created to support the study that the campus is a safe place to be, including axial mapping and analysis mapping, convex mapping and grid analysis mapping. This with a combination of survey shall be used to understand safety with respect to space syntax. ZEMCH Network. -
Photovoltaic Structures Using Thermally Evaporated SnS and CDS Thin Films
Thin Solid Films, Vol-545, pp. 543-547. ISSN-0040-6090 -
Optical and electrical properties of SnS semiconductor crystals grown by physical vapor deposition technique
Tin sulfide (SnS) is a material of interest for use as an absorber in low cost solar cells. Single crystals of SnS were grown by the physical vapor deposition technique. The grown crystals were characterized to evaluate the composition, structure, morphology, electrical and optical properties using appropriate techniques. The composition analysis indicated that the crystals were nearly stoichiometric with Sn-to-S atomic percent ratio of 1.02. Study of their morphology revealed the layered type growth mechanism with low surface roughness. The grown crystals had orthorhombic structure with (0 4 0) orientation. They exhibited an indirect optical band gap of 1.06 eV and direct band gap of 1.21 eV with high absorption coefficient (up to 103 cm-1) above the fundamental absorption edge. The grown crystals were of p-type with an electrical resistivity of 120 ? cm and carrier concentration 1.52015 cm-3. Analysis of optical absorption and diffuse reflectance spectra showed the presence of a wide absorption band in the wavelength range 3001200 nm, which closely matches with a significant part of solar radiation spectrum. The obtained results were discussed to assess the suitability of the SnS crystal for the fabrication of optoelectronic devices. 2011 Elsevier B.V. All rights reserved. -
Vacuum annealed tin sulfide (SnS) thin films for solar cell applications
Thin films of tin sulfide (SnS) were grown on a glass substrate at an optimum temperature of 300 C by thermal evaporation technique. Following the deposition, films were vacuum annealed at different temperatures in the range of 100 to 300 C for 2 h. The effect of annealing temperature (Ta) on the composition, surface morphology, microstructure, optical and electrical properties was investigated. Elemental analysis showed sulfur deficiency of annealed films and the Sn to S atomic percent ratio increased from 1.0 to 1.1. XRD analysis confirmed the orthorhombic crystal structure of the films with (111) preferred orientation and phase purity. Degree of preferred orientation decreased with increase in Ta and the diffraction peaks corresponding to other planes intensified. Increasing the Ta to 300 C led to an increase in crystallite size to 129 nm. Results indicated presence of several crystallites in the grains of as-deposited films. AFM studies revealed the fragmentation of larger grain and the average grain size reduced form 265 nm for as-deposited films to 132.8 nm for the film annealed at 300 C. An apparent shift in absorption edge towards longer wavelengths is observed for films annealed at Ta > 200 C. The optical constant such as optical band gap, extinction coefficient (k), absorption coefficient (?) and refractive index (n) have been evaluated. The optical band gap of SnS thin films varied marginally with the annealing temperature and remained in between 1.331.29 eV. The extinction coefficient of the film annealed at 300 C was enhanced and is found to be 0.85 at 700 nm. At the annealing temperature of 300 C, the SnS films had enhanced electrical properties: the electrical resistivity was 7.8 ? cm, the p-type carrier concentration was up to 2.17 1016 cm?3, and the mobility was about 36.9 cm2V?1s?1. The variation of physical parameters with Ta has been explained by taking into account the crystallite size and the presented values are discussed with relevance to solar cells. 2017 Elsevier B.V. -
Photovoltaic structures using thermally evaporated SnS and CdS thin films
Polycrystalline tin sulfide thin films were prepared by thermal evaporation technique.The films grown at substrate temperature of 300 C had an orthorhombic crystal structure with strong preferred orientation along (111) plane.Electrical resistivity of the deposited films was about 32.5 ? cm with a direct optical band gap of 1.33 eV.Carrier concentration and mobility of charge carriers estimated from the Hall measurement were found to be 6.24 1015 cm- 3 and 30.7 cm2V- 1 s- 1 respectively.Heterojunction solar cells were fabricated in superstrate configuration using thermally evaporated SnS as an absorber layer and CdS, In:CdS as window layer.The resistivity of pure CdS thin film of a thickness of 320 nm was about 1-2 ? cm and was reduced to 40 10- 3 ? cm upon indium doping.The fabricated solar cells were characterized using solar simulator.The solar cells with indium doped CdS window layer showed improved performance as compared to pure CdS window layer.The best device had a conversion efficiency of 0.4% and a fill factor of 33.5%. 2013 Elsevier B.V.All rights reserved. -
Microhardness studies of vapour grown tin (II) sulfide single crystals
Earth abundant tin sulfide (SnS) has attracted considerable attention as a possible absorber material for low-cost solar cells due to its favourable optoelectronic properties. Single crystals of SnS were grown by physical vapour deposition (PVD) technique. Microindentation studies were carried out on the cleaved surfaces of the crystals to understand their mechanical behaviour. Microhardness increased initially with the load, giving sharp maximum at 15 g. Quenching effect has increased the microhardness, while annealing reduced the microhardness of grown crystals. The hardness values of as-grown, annealed and quenched samples at 15 g load are computed to be 99.69, 44.52 and 106.29 kg/mm 2 respectively. The microhardness of PVD grown crystals are high compared to CdTe, a leading low-cost PV material. The as-grown faces are found to be fracture resistant. 2015 AIP Publishing LLC.