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Effect of magnetic field on the onset of Rayleigh-Benard convection in a micropolar fluid with internal heat generation
The effects of through flow, internal heat generation and magnetic field on the onset of Rayleigh-Benard convection in electrically conducting Micropolar fluid are studied using the Galerkin technique. The eigenvalue is obtained for rigid-free velocity boundary combinations with isothermal and adiabatic on the spin-vanishing boundaries. A linear stability analysis is performed. The influence of various parameters on the onset of convection has been analyzed. The microrotation is assumed to vanish at the boundaries. A linear stability analysis is performed. The influence of various parameters on the onset of convection has been analyzed and their comparative influence on onset is discussed. The problem suggests an elegant method of external control of internal convection. -
EFFECT OF MAGNETIC FIELD ON THE ONSET OF RAYLEIGH-B??NARD CONVECTION IN A MICROPOLAR FLUID WITH INTERNAL HEAT GENERATION
The effects of through flow, internal heat generation and magnetic field on the onset of Rayleigh-B??nard convection in electrically conducting Micropolar fluid are studied using the Galerkin technique. The eigenvalue is obtained for rigid-free velocity boundary combinations with isothermal and adiabatic on the spin-vanishing boundaries. A linear stability analysis is performed. The influence of various parameters on the onset of convection has been analyzed. The microrotation is assumed to vanish at the boundaries. A linear stability analysis is performed. The influence of various parameters on the onset of convection has been analyzed and their comparative influence on onset is discussed. The problem suggests an elegant method of external control of internal convection. -
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Effect of internal heat source modulations on the onset of triple diffusive convection in viscoelastic liquids
The paper aims to study the dynamic behavior of a triple diffusive system subjected to sinusoidal (trigonometric cosine) and non-sinusoidal wave forms (square, sawtooth and triangular) of internal heat source modulation. The configuration of the system is such that a layer of viscoelastic liquid is heated and salted with two solutes from below. An Oldroyd-B type model is made use for viscoelastic liquids. In order to regulate the convection onset, internal heat source modulation is applied. This investigation is modelled using a linear stability analysis where a stationary convection is preferred. Venezian approach facilitates a solution by finding the eigen values of the problem. The influence of pertinent parameters which are varied for a wide range of values have been reported. It is captured via graphs that for small values of frequency of modulation, square wave form is more stable while sawtooth wave form is more stable for an increment in the values of frequency of modulation. Further, liquids such as Newtonian, Maxwell and Rivlin-Ericksen are analysed as the limiting cases of the problem. It seems worthwhile to discuss the results of the present study as it is the first work on linear theory of different wave forms of internal heat source modulation and thus paves a way for new theoretical and experimental endeavors. 2021, National Institute of Science Communication and Information Resources. All rights reserved. -
EFFECT OF INTERNAL HEAT GENERATION ON THE ONSET OF RAYLEIGH-B??NARD- MARANGONI MAGNETO CONVECTION IN A HORIZONTAL LAYER OF FLUID WITH SUSPENDED PARTICLES
The effects of internal heat generation and magnetic field on the onset of Rayleigh-B??nard-Marangoni convection in electrically conducting Micropolar fluid are studied using the Galerkin technique. In the case of Rayleigh??B??nard convection, the eigenvalue is obtained for rigid-free velocity boundary combinations with isothermal and adiabatic on the spin- vanishing boundaries. A linear stability analysis is performed. The influence of various parameters on the onset of convection has been analyzed. In the case of Marangoni and Rayleigh-B??nard-Marangoni convection the eigenvalues are obtained for an upper free / adiabatic and a lower rigid / isothermal boundaries. The microrotation is assumed to vanish at the boundaries. A linear stability analysis is performed. The influence of various parameters on the onset of convection has been analyzed and their comparative influence on onset is discussed. The problem suggests an elegant method of external control of internal convection. -
Effect of inoculum density and different media on the growth of hairy roots and production of withanolide-A from withaniasomnifera /
Mapana Journal of Sciences, Vol. 16(4),pp.13-22. ISSN 0975-3303. -
Effect of impulse buying on socioeconomic factors and retail categories /
Indian Journal of Marketing, Vol.46, Issue 9, ISSN: 0973-8703. -
Effect of impulse buying on socioeconomic factors and retail categories
The study aimed to determine the impulse buying behaviour of shoppers at apparel multi-brand outlets using socio-economic factors and retail categories. The research is a descriptive one, and it was conducted among 400 Indian respondents. This research was carried out to identify the impulsive behaviour of respondents at multi-brand outlets because it occurs high in organized retail stores due to attractive displays and latest design and collections. The study revealed that impulse buying behaviour varies among the distinct age profile. The study found that men shop more impulsively than women. The impulse buying did not have a high impact on changes in monthly family income of the respondents. The impulse buying behaviour was displayed more within the same multi-brand outlets than the other retail categories. -
Effect of Impulse Buying on Socio-economic factors and Retail Categories
Indian Journal of Marketing, Vol. 46, Issue 9, pp. 24-34, ISSN No. 0973-8704 -
Effect of Imposed Time-Periodic Gravity Modulation and Electric Field on the Onset of Rayleigh-Benard Convection in a Couple Stress Fluid
International Journal of Mathematical Sciences and Engineering Applications, Vol-6 (6), pp. 421-435. ISSN-0973-9424 -
Effect of imposed time periodic boundary temperature on the onset of Rayleigh-Benard convection in a dielectric couple stress fluid /
International Journal of Applied Mathematics and Computation, Vol.5, Issue 4, pp.400-412, ISSN No: 0974-4665 (Print), 0974-4673 (Online) -
Effect of hooked end steel fibers on strength and durability properties of ambient cured geopolymer concrete
Growing carbon emissions in the construction industry have warranted the use of alternative materials such as geopolymer concrete. At the same time exposure of concrete material to harsh environmental conditions has compelled to design of durable geopolymer concrete. The use of hooked-end steel fibers in conventional fiber-reinforced concrete has proven to improve its crack resistance, and thus, positively influence the durability properties of concrete structures. Nevertheless, limited studies explore the effect of hooked-end steel fibers on the strength and durability properties of ambient cured geopolymer concrete with a low NaOH content (i.e., 8 M concentration). In this study, ambient cured geopolymer concrete was prepared by fly ash, ground granulated blast furnace slag (GGBS), NaOH, Na2SiO3, manufactured sand, and natural coarse aggregates. Additionally, hooked-end steel fibers with an aspect ratio of 67 were added to the mix by volume fraction in dosages of 0 %, 0.5 %, 1 %, 1.5 %, and 2 %. The experimental results showed that the addition of fibers reduced the workability with a minimum slump of 70 mm and a maximum Vee Bee time of 8 s for mixes with 2 % steel fibers. The addition of fibers improved the compressive strength, split tensile strength, and flexural strength of geopolymer concrete, with a maximum strength of 41.44 MPa, 4.28 MPa, and 5.23 MPa at an optimum fiber dose of 1 %, respectively. Above the optimum dose, the strength of the steel fiber-reinforced geopolymer concrete (SFRGPC) was reduced. The depth of water penetration reduced in SFRGPC when compared to GPC. Moreover, the resistance to chloride ion penetration was not significantly affected by addition of steel fibers till optimum dose of 1 %. The scanning electron microscopic results revealed the positive effect of steel fibers in restricting the progression of cracks. This has resulted in smaller crack width in the SFRGPC when compared to GPC. Overall, steel fibers in optimum dose have improved the performance of geopolymer concrete and this will contribute towards low carbon material. 2023 The Authors -
Effect of homogeneous chemical reaction on the dispersion of a solute in a threedimensional flow of a Newtonian liquid through a porous medium
All-Time dispersion of a reactive solute in a Newtonian fluid flow through a Darcy-Brinkman-Forchheimer Porous medium is carried out using the approach of Gill - Sankarasubramanian (1970) and Doshi etal. (1978). The velocity profile of the non - linear porous medium flow equation is solved using the Maclaurin series of two variables. The three - dimensional model brings into the focus the convective and dispersion coefficients. The chemical reaction is assumed to be homogeneous. The chemical reaction is shown to increase the value of the convective coefficient while it decreases with increase in the value of the reaction rate parameter. The effect of the presence of the porous medium is to decrease the flow and hence the convective coefficient. Similar effect of the porous parameter is seen on the dispersion coefficient. The reaction rate parameter and the porous parameter have opposite effect on the mean concentration distribution. 2023 Taylor & Francis Group, LLC. -
Effect of heavy metals on the pigmentation and photosynthetic capability in Jacobaea maritima (L.) Pelser & Meijden
Photosynthesis is a fundamental process in plants that enables them to produce their own food. However, this process can be influenced by multiple factors including external factors such as sunlight, nutrients availability and gas concentrations. The present study aimed to investigate the effects of heavy metal stress on the plant Jacobaea maritima (L.) Pelser & Meijden. Three different heavy metals, namely cadmium, chromium, and lead, were applied to the plants at five concentrations ranging from 50-250 ppm (50, 100, 150, 200, and 250). The growth of the plants was observed, and several parameters including net photosynthetic rate (Pn), transpiration rate (E), leaf stomatal conductance (C), and the photosynthetic active radiation (PAR) were measured. The results revealed that the chlorophyll content was higher in the Cr150 concentration (5.470.4). The chlorophyll values for Pb-100 (9.40.35) and Pb-250 (9.80.26) were in close proximity to each other. The Cd-100 concentration showed the highest chlorophyll content. The net photosynthetic rate was least affected in Pb-150 (30.980.75), while Cr-100 (4.050.09) exhibited the greatest impact. Transpiration rate increased slightly in plants treated with Pb, but significantly decreased in Cd-treated plants. The Cr-50 concentration (0.190.02) showed the lowest transpiration rate. Leaf stomatal conductance was reduced significantly in all treated plants, with Cr-100 showing the least variation (2298.251.85). The photosynthetic active radiation capability was reduced in all treated plants, with Pb-treated plants exhibiting nominal reduction and Cd- and Cr-treated plants experiencing substantial reduction. Statistical analysis confirmed significant variations in the measured parameters following heavy metal treatment. 2023 The Author(s) -
Effect of heavy metals on the andrographolide content, phytochemicals and antioxidant activity of Andrographis paniculata
Andrographis paniculata is a medicinal plant that has several medicinal properties and has been traditionally used in different medicinal preparations. The present study deals with the influence of heavy metals (lead, mercury and silver) on andrographolide, phytochemicals and antioxidant activity in Andrographis paniculata. Two months old saplings were subjected to heavy metal stress of two different concentrations (0.2 mM and 0.4 mM) for three different times at 3 day time interval. The results showed that the saplings treated with heavy metals showed increased concentration of andrographolide content. The saplings treated with 0.4 mM silver showed the highest increase in the andrographolide content (24.58 2.85 mg/g of DW) compared with control (9.41 1.26 mg/g of DW) and other treatments. Variations in the biochemical parameters like total phenolic content, total flavonoid content, etc. were also prominent with all the treated samples when compared to that of control. 2020 Chemical Publishing Co.. All rights reserved. -
Effect of heavy metals on germination, biochemical, antioxidant and withanolide content in Withania somnifera (L.) Dunal
Withania somnifera (L.) Dunal., commonly referred to as Ashwagandha, is a medicinal plant from the solanaceae family with a wide range of pharmacological properties. W. somnifera is a rich source of withanolides, such as withanolide A, withanolide B, withanolide D, withaferin A and many others which are attributed for a large number of pharmacological activities. In the present study, the impact of heavy metals such as cadmium (Cd), mercury (Hg) and lead (Pb) has been assessed on the growth, biochemical parameters, antioxidant activity and withanolide A and withaferin A content of W. somnifera. The seeds of W. somnifera were germinated in cocopeat and treated with different concentrations of Cd (20-200 ppm), Hg (10-100 ppm) and Pb (200-2000 ppm) for 21 days. There have been substantial differences between the heavy metal-treated plants and the control plants with the lowest germination of 20% observed in the plants treated with 2000 ppm Pb. The selected metals inhibited vegetative growth with lowest length of 3.07cm and lowest biomass of 0.74g in 180 ppm Cd and 200 ppm Cd treated plants respectively. With the addition of heavy metals, biochemical parameters like protein, carbohydrate, chlorophyll, total phenol, flavonoid and proline content varied significantly and showed metal tolerance by exhibiting antioxidant activity at lower concentrations. The metal accumulation occurred in a dose-dependent manner with highest Cd accumulation of 14.30mg kg?1, Hg accumulation of 42.45mg kg?1, and Pb accumulation of 217.46mg kg?1 of dry biomass of the plants. The withanolide content increased up to a specific metal concentration and decreased with a further increase in heavy metal concentration. The seeds treated with 1200 ppm of Pb showed the highest withanolide A content of 1.7mg g?1 dry weight (DW), and the seeds treated with 80 ppm of Cd showed the highest withaferin A content of 3.2mg g?1 DW. 2023 Horizon e-Publishing Group. All rights reserved. -
Effect of heavy metals on germination, biochemical, and L-DOPA content in Mucuna pruriens (L.) DC.
Mucuna pruriens (L.) DC. is a medicinal plant with a wide range of pharmacological properties that have been used in various medicinal preparations for centuries. M. pruriens is a rich source of levodopa (L-DOPA), mainly used to treat Parkinsons disease. The present study investigates the impact of heavy metals such as cadmium (Cd), mercury (Hg), and lead (Pb) on the growth parameters and biochemical characteristics, including the L-DOPA content of M. pruriens. The seeds of M. pruriens were treated with different concentrations of Cd (0250 ppm), Hg (0250 ppm), and Pb (02000 ppm) for 21 days. On exposure to heavy metals, the germination %, the vegetative growth, and the biochemical characteristics such as the protein, carbohydrate, chlorophyll, total phenol, flavonoid, and proline content varied significantly in the heavy metal-treated plants when compared to control. It was also observed that the L-DOPA content increased with increased metal concentration and then decreased further with higher concentration of metals. The metal accumulation increased with the increase in the metal concentration. The seeds treated with 1000 ppm of Pb showed the highest L-DOPA content compared with control and other treatments. 2022 Banadka and Nagella. -
Effect of heavy metal stress on biochemical and antioxidant efficacy of Chamaecostus cuspidatus
Chamaecostus cuspidatus, commonly known as insulin plant is medicinally important and a rich source of several secondary metabolites which exhibit pharmacological properties. In the present study, three different heavy metals (Pb, Cu and Cr) with different concentrations (Pb and Cr-50, 100, 150, 200 and 250 ppm and for Cu 25, 50, 75, 100 and 125 ppm) was used for heavy metal treatment and its impact on several biochemical and antioxidant parameters was measured of the test plant along with control. Current study mainly focuses on the biochemical and antioxidants estimation of root and rhizome of C. cuspidatus. Protein, proline and carbohydrate content was increased in the treated groups. Total phenol and total flavonoid content were also found to be increased in all the treated groups. Both enzymatic (SOD, CAT, APX) and nonenzymatic antioxidants (DPPH, FRAP and total antioxidant activity) was measured. Antioxidant activity was also high in the treated groups. Highest DPPH activity was found in Cu 25 treated rhizome 91.8030.157 and lowest was observed in Pb 50 treated root 4.5530.240. Highest reducing power activity (FRAP) was observed in Cr 100 treated rhizome 0.75860.0008 and least was found in control root 0.2090.0005. Heavy metals accumulation was also measured and maximum heavy metal accumulation was found in soil following by root and rhizome of all the treated groups. 2024, Indian journals. All rights reserved. -
Effect of Heat Treatment on Fatigue Characteristics of En8 Steel
Fatigue failure is an important factor in most of the engineering applications, especially in steel materials, and among the steel materials, it is an important phenomena in medium carbon steels like EN8, which is very commonly used in components like shaft, gears etc., since it is prone to fatigue failure. Hence, without changing the composition, an attempt is made to enhance the fatigue strength by different heat treatment techniques. In this study, the investigation is carried out on heat treatment of EN8 steel material. Various kinds of heat treatment techniques like quench and temper, normalizing and annealing are performed on EN8 steel. After exposure to the heat treatment, the EN 8 steel material specimens are machined as per the ASTM standards and are subjected to RR MOORE test and SN-curves are plotted from the obtained results; the obtained results from the fatigue tests are further analyzed with the help of ANSYS software. Fatigue life and Factor of Safety (FOS) comparisons for EN 8 steel material is made with the structural steel material and it is found from the comparisons, that the heat treatment process enhances the fatigue strength and endurance limit. Published under licence by IOP Publishing Ltd. -
Effect of heat treated HNT on physico-mechanical properties of epoxy nanocomposites
Halloysite Nano Tubes (HNTs) are naturally occurring Kaolite group minerals having an aluminosilicate-layer in the form of nanotubes which are known to enhance the properties of the polymer matrix composites when effectively dispersed in the epoxy matrix phase. In this regard, the present work is carried out to fabricate the composite specimens by polymer stir casting techniques and evaluate the basic properties viz., density, hardness, tensile strength, flexural strength, impact strength and the microstructure using Transmission electron microscopy (TEM) for better morphological studies of the dispersions in the nanocomposites with a filler content of 0, 5 and 10 wt% of HNT's that are effectively treated at three temperature conditions viz., Room temperature (RT), 50 C and 70 C according to specified ASTM test methods selected after thorough investigations and review of literature. As per the experimental investigation, the mechanical properties of the nanocomposite increases by the incorporation of heat treated HNT. Further, the study revealed that the nano composite with a filler content of 10 Wt.% of HNT preheat treated at 50 C shows superior tensile and flexural strength, However the critical observation of the results reveal that the impact strength is maximum for Nano composites with a filler content of 5 Wt.% HNT pre heat treated at 70 C. The study of TEM images gives an overview of uniform dispersion of HNTs in the matrix phase owing to varying pre-treatment conditions. It is evident that the properties of the nanocomposite depends on the quantity of functional filler present and temperature of heat treatment. 2019 Elsevier Ltd