Rise Height Research Articles

Elucidating sorptive eradication of ibuprofen using calcium chloride caged bentonite clay and acid activated alginate beads in a fixed bed upward flow column reactor

The sorptive eradication of ibuprofen (IBP), a pharmaceutical micro-pollutant, from aqueous medium in a fixed bed upward flow column reactor was examined using the adsorbent prepared from amalgamation of calcium chloride caged acid activated tamarind seed and bentonite alginate beads [Ca2+(TAABB)Al]. Surface texture and the presence of constituent elements in the contrived sorbent was characterised by scanning electron microscopy and energy dispersive x-ray analysis at pre-sorption and post-sorption phases. Effect of controlling factors viz. bed height of the column (5–25 cm), influent concentration of IBP (10–25 mg/L), and amount of inflow (2–6 mL/min) on efficacious IBP uptake was evaluated. The column experimentation revealed that there would be a rise in height of the breakthrough curve while the column bed height increases. Along with 97.48% IBP elimination, the maximal adsorbent uptake has been determined to be 17.54 mg/g from an optimum height of column bed of 20 cm, concentration of influent ibuprofen 20 mg/L, and amount of inflow 2 mL/min. Efficiency of the sorbent was investigated using the bed depth service time (BDST) model, and it was observed that bed height of the column was the most important aspects in achieving effective IBP adsorption. The investigational results were well supported by the Yoon–Nelson as well as Thomas model. The desorption analysis demonstrated the performance of adsorbent up to 5 cycles for ibuprofen separation with a column regeneration rate of 38.14%. Hence, the novel sorbent Ca2+(TAABB)Al can be effectively used to eradicate IBP from aqueous phase.

Thermokinetics of capillary absorption and its application in cement-based materials

Capillary water can transmit in capillary tube induced by hydrostatic pressure, which has an important impact on the durability and shrinkage of concrete. In this study, the ultimate height of capillary rise under various conditions was analyzed based on thermodynamic equilibrium of capillary water where capillary water is subjected to six types of force. Subsequently, a logarithmic model of capillary rising with three parameters (Jurins's height hc, permeability coefficient k, characteristic time τ) was proposed according to the analytical solution of kinetics function of capillary absorption. To better understand capillary behavior in capillary bundle with different radius, the spatio-temporal distribution of saturation, and the variation of water content with time and saturation are predicted according to the kinetics of capillary rise in single capillary. Additionally, the kinetics of capillary absorption in porous materials was discussed. Finally, the developed model was verified by testing the true rising height of water in a mortar specimen using X ray computed tomography. The equivalent height of adsorbed water in mortar with varied saturation under different time was obtained by gravimetric method. The results show that the logarithmic model gives a good description of the kinetics data of water absorption in mortar.

Analysis of intra-particle liquid capillary spread mechanisms in high-temperature stope leaching using MRI

Capillary penetration is widely existed in stope leaching, both the rate of liquid wetting ore and flow out of ore are affected by it. Stope leaching is carried out in a high-temperature environment when mining minerals with large burial depth. The mechanism of intra-particle liquid capillary penetration mechanisms at high-temperature have not been revealed. In this paper, samples with a size of Φ50 mm × 100 mm were selected for quantitative analysis. The capillary rise behaviour inside samples with different porosity were detected at 30 °C, 40 °C and 50 °C by using magnetic resonance imaging (MRI). In most cases, capillary rise height is underestimated when the outside wetting line is used as an indicator, because the rise height inside the sample is greater. The liquid capillary rise height increased slightly with the temperature, whereas the wetting surface profile remained unchanged. The capillary rise rate increased significantly with porosity, mainly due to the increase of internal effective porosity. The results help to understand the liquid penetration behaviour under high-temperature stope leaching condition, and lay a theoretical foundation for improving the liquid permeability.

Experimental studies on soot in MILD oxy-coal combustion flame: Sampling, microscopic characteristics, chemical compositions and formation mechanism

Based on a diffusion-flamelet-based Hencken burner, the effect of temperature on the volume fraction of soot was explored firstly. The temperature of MILD oxy-coal (MILD-OCC) flame was measured by temperature measuring device and the volume fraction of soot was obtained by the thermocouple deposition method. Then the mass concentration, microstructure, nanostructure parameters (the distribution of particle size, the length of crystallite, the curvature of crystallite, the layer spacing of crystallite) and chemical compositions of soot were studied. The soot particles generated from MILD-OCC flame were harvested by thermophoretic sampling system and capillary sampling system, and measured with the combination of field emission transmission electron microscopy (TEM) and gas chromatography-mass spectrometry analyzer (GC-MS). The results showed that as the height of MILD-OCC flame increased, the degree of agglomeration of soot particles increased. The surface growth and oxidation existed at the same time and were in a competitive relationship, which manifested in the mass concentration of soot, the average distribution of particle size and the content of aromatic compounds. With the rise of flame height, the average length of the crystallite increased while the average curvature of the crystallite and the average crystalline layer spacing showed a decreasing trend, which showed that the microstructure of soot became more mature and orderly. These results are valuable for further understanding the formation mechanism of soot.

Free surface features of submarines moving underwater: Study of Bernoulli Hump

Submarines are known to produce certain surface manifestations, primary among them being a feature known as Bernoulli Hump (BH). BH is a rise and fall of sea surface height above the submarine, when the vessel cruises close to surface. This feature has been noted by many researchers but scant information is publically available on the same due to the classified nature of the data. A major part of the Wide Area Surveillance program for submarines of the world navies uses the detection of this BH. In this work, our objective is to detect and establish the presence of BH characteristics. After calibrating a known CFD code using experimental data, we make model simulations which clearly depict the BH and its features. We then show the path ahead for submarine detection using BH from observations of sea surface heights. Value of BH height for a submarine at 10m depth moving at 5 knots is about 20cm which falls within the 2 cm vertical resolution of altimeters. Though most of the studies were for calm waters, an introduction to the presence of regular wind waves is given at the end.

Evaporative capillary rise

We investigate the rise dynamics of a volatile liquid within an open vertical channel, which requires us to consider the effects of capillarity, gravity, viscosity, and evaporation together. Upon quantifying the enhanced evaporation near the solid-liquid-gas contact line and setting up a theoretical model for the rise height, we show how to find an optimal channel dimension that maximizes the equilibrium rise height. This work can lay a foundation for understanding the evaporative capillary rise dynamics occurring in porous media.

Experimental study on capillary water absorption of sandstones from different grotto heritage sites in China

Sandstone grottoes, with their elaborate carvings and decorations, hold high historic, artistic and scientific values and therefore constitute an important part of China’s stone cultural heritage. Although capillary water accounts for severe pathologies at the grottoes, so far there have been limited comprehensive investigations concerned with the capillary water absorption behavior of sandstones. Aiming at three significant and famous sites in China, i.e., Yungang Grottoes (YG), Dazu Rock Carvings (DZ) and Leshan Grand Buddha (LS), capillary water absorption tests were performed on samples from local sandstones. During the test, evolution of cumulative inflow was measured and variation in the height of capillary rise over time was also monitored by combining visual observation and infrared thermography. Scanning electron microscope and mercury intrusion porosimetry were adopted to characterize the pore structure. The results indicate that all the tested sandstones had a medium capacity of water uptake. Kinetics for capillary water absorption was the highest for LS sandstone and the lowest for DZ sandstone. Differences in macroscopic properties were contributed to microstructural features such as average pore diameter and pore size distribution. An irregular shaped water front was only observed in LS sandstone due to its heterogeneity. Infrared thermography provides an efficient and nondestructive way to detect the transition zone between wet and dry portions of the sample, which was not visible to the naked eyes. A proper understanding of the interaction of the sandstones with capillary water is essential for revealing the deterioration of grottoes and the underlying mechanisms.

Observational study of the PM2.5 and O3 superposition-composite pollution event during spring 2020 in Beijing associated with the water vapor conveyor belt in the northern hemisphere

Unlike the heavy haze situations in previous years, the emergence of a water vapor conveyor belt flowing through North China is an important factor in the foggy-haze event during the 48-h snowfall in Beijing and its surroundings, which disrupted the customary pollution snow removal atmospheric purification.①In the spring of 2020, during a period of negative emissions increment and weak human activity impact, a special interaction between the high humidity content of large-scale continuous water vapor transmission and the weather-scale daily cycling radiation cycle change (due to daily change of sun's zenith angle), as well as the atmospheric microphysical process, provided rare meteorological conditions for the superposition-compound growth of PM2.5 and O3 pollution. The water vapor conveyor belt, through enhanced transmission of easterly wind momentum, induced a high value super-saturation signal (S) and condensation rate (fc), resulting in 48 consecutive hours of snow in Beijing, but was also conducive to fine particulates, including precursor emissions, through a microphysical humidification process, which became synchronized. ②The weather-scale process impact refers to the cloud height rise in the daytime and decrease at night. Due to the daily fluctuations in cloud height, the concentration of O3 followed a coordinated daily cycle. During the day, when the sun's zenith angle going on the top, the PM2.5 and O3 superposition composite effects occur. Therefore, even during a negative emission period, PM2.5 and O3 superposition-composite serious pollution events occur as usual, rather than the expected possible atmospheric cleaning through snow.

Flow regimes characteristics of industrial-scale center-rising airlift reactor

• Multiphase fluids in industrial-scale CRALR exhibit unique flow characteristics. • Δ P - u g curves increase stepwise with gradually rising in distributor hole area. • Pressure accumulation and release in large distributor form gas-liquid oscillations. • Increase of the CRALR diameter induces the bubble stream to rotate in advance. • Limit of gas holdup is determined by equipment parameters. Airlift reactors are frequently preferred in biochemical engineering, and related investigations are almost performed using bench-scale reactors. However, in industrial-scale reactors, multiphase fluid usually exhibits unique mixing and transfer behaviors. Therefore, we studied the flow regimes characteristics in an industrial-scale center-rising airlift reactor (CRALR) with a diameter of 1.2 m. The results show that the available jet hole area of the gas distributor gradually increases along with the superficial gas velocity in the plateau range of the total pressure drop. Since the rise in initial liquid height enlarges the available jet hole area, the flow regime can be transformed from a pure heterogeneous regime to other regimes. Meanwhile, the total gas holdup plunges within the transition regime range, which can be interpreted by the gas–liquid oscillations in the gas distributor with a large free gas volume. When the oscillations cannot maintain the small bubble ratio, the rapid transition from a homogeneous regime to heterogeneous regime is affected. Compared with previous results, the bubble stream rotates in advance in the homogeneous regime of the industrial-scale CRALR. The rotational structure helps to reduce the flow resistance and improves the radial bubble distribution. Furthermore, the total gas holdup curves under various operating conditions converge into one curve at which a limit, determined by equipment parameters, is ultimately reached in the course of increasing the superficial gas velocity. It turns out that the fluids have similar hydrodynamic behaviors in flow fields of different scales when the limit is reached.

Hydrodynamics of horizontal heated buoyant jet in linearly stratified fluids

Horizontal buoyant jets in stratified fluids are investigated by employing a computational fluid dynamic model validated by experimental data. The characteristics of time mean flow, turbulence, and entrainment are quantified. We observed that turbulence parameters such as the turbulent kinetic energy, the turbulence dissipation rate, and turbulent viscosity attained their maximum values in the horizontal region. Here, the entrainment coefficient also reaches the maximum due to the instantaneous instability of the flow. The ascent region consists of the acceleration and deceleration stages due to the stratified ambience reversing the sign of buoyancy flux. In the acceleration ascent region, the entrainment coefficient stabilizes around 0.05. In the deceleration stage, the transition of the flow regime from plume- to jet-like regulates the entrainment. At the end of the ascent region, the jet reaches the maximum rise height (Hmax), which can be well predicted by a semiempirical function at a given Richardson number, buoyancy frequency, and Reynolds number. An enhancement of turbulent parameters is observed near the Hmax and could be attributed to overshooting and shearing between the up- and downflow. Analysis of density and velocity profiles shows the heavy fluids on the lower side of the jet core vertically separating from the center fluids, which drifted the velocity profile from a Gauss to a fat-tailed distribution and broke the self-similarity.

Dynamic Effects during the Capillary Rise of Fluids in Cylindrical Tubes.

The mathematical models for the capillary-driven flow of fluids in tubes typically assume a static contact angle at the fluid-air contact line on the tube walls. However, the dynamic evolution of the fluid-air interface is an important feature during capillary rise. Furthermore, inertial effects are relevant at early times and may lead to oscillations. To incorporate and quantify the different effects, a fundamental description of the physical processes within the tube is used to derive an upscaled model of capillary-driven flow in circular cylindrical tubes. The upscaled model extends the classical Lucas-Washburn model by incorporating a dynamic contact angle and slip. It is then further extended to account for inertial effects. Finally, the solutions of the different models are compared to experimental data. In contrast to the Lucas-Washburn model, the models with dynamic contact angle match well the experimental data, both the rise height and the contact angle, even at early times. The models have a free parameter through the dynamic contact angle description, which is fitted using the experimental data. The findings here suggest that this parameter depends only on the properties of the fluid but is independent of geometrical features, such as the tube radius. Therefore, the presented models can predict the capillary-driven flow in tubular systems upon knowledge of the underlying dynamic contact-angle relation.

Effects of women's footwear on the mechanical function of heel-height accommodating prosthetic feet.

The loaded mechanical function of transtibial prostheses that result from the clinical assembly, tuning, and alignment of modular prosthetic components can directly influence an end user’s biomechanics and overall mobility. Footwear is known to affect prosthesis mechanical properties, and while the options of footwear are limited for most commercial feet due to their fixed geometry, there exists a selection of commercial prosthetic feet that can accommodate a moderate rise in heel height. These feet are particularly relevant to women prosthesis users who often desire to don footwear spanning a range of heel heights. The aim of this study was to assess the effects of adding women’s footwear (flat, trainer, 5.08 cm heel) on the mechanical properties (deformation and energy efficiency) of four models of heel-height accommodating prosthetic feet. Properties were measured through loading-unloading at simulated initial contact, midstance and terminal stance orientations with a universal materials test system, and statistically compared to a barefoot condition. Results suggest that the addition of footwear can alter the level of foot deformation under load, which may be a function of the shoe and alignment. Moreover, while each foot displayed different amounts of energy storage and return, the addition of footwear yielded similar levels of energy efficiency across foot models. Overall, prosthesis users who don shoes of varying heel heights onto adjustable prosthetic feet and their treating clinicians should be aware of the potential changes in mechanical function that could affect the user experience.

Effects of Frequency and Joule Heating on Height Rise between Parallel Electrodes with AC Electric Fields.

High strength AC electric fields generate a body force on a dielectric medium confined between two electrodes. The body forces are due to two factors. First is the variation in permittivity across an interface such as liquid-air present between the electrodes. The second is a change in the dielectric property of the medium due to a variation in the thermodynamic properties such as temperature. The height rise of a dielectric medium between two electrodes is one of the consequences of these electrical body forces and is used here as a comparatively simple way to study these forces. In an aqueous solution with finite conductivity, the effects of the frequency of the supplied voltage source and the temperature change due to Joule heating on height rise have never been studied in this context. This study focuses on systems where the contributions of surface forces are negligible and highlights the interplay between solution conductivity, applied electric field, and the solution height/temperature behavior. Using a generic thermodynamic model for an aqueous solution under the application of an alternating current electric field, it is shown that for low conductivity solutions the resulting temperature and height rise change weakly with the applied field frequency and strongly with the applied electric field. For higher conductivity solutions, the behavior becomes more complex with respect to the electric field strength. As compared to Pellat's original model, the height rise varies from strongly suppressed to enhanced.

Sensitivity Test of Jet Velocity and Void Fraction on the Prediction of Rise Height and Performance of a Confined Plunging Liquid Jet Reactor

Jet velocity is an important parameter affecting the air entrainment rate of plunging liquid jet processes. While the vast majority of researchers have investigated the effect of jet velocity, only a few of them considered the effect of jet length in calculating the jet velocity at impingement point. This study investigates the difference (ΔV) between the jet velocity at the inception of the nozzle (Vj) and the impingement point (VL) for a range of operating conditions. Furthermore, bubble voidage inside the downcomer, another critical parameter in plunging jets, is estimated using three different voidage equations incorporated inside a momentum balance model to predict the two-phase elevation level (HR) inside the downcomer. Results showed that ΔV is significant (VL > Vj), especially at low jet flow rates and high jet lengths. Generally, the momentum balance model predicted the HR well, and its prediction improves with downcomer diameter. Given that, the model still needs to be refined for more accuracy for a wide range of operating conditions.

Factors controlling the rise and fall of groundwater level during the freezing-thawing period in seasonal frozen regions

Freezing- and thawing-induced variations of groundwater level and the corresponding changes in water storage in the saturated zone have been observed in regions with a shallow water table. However, the vertical migration of water under the effect of the freezing-thawing process on shallow groundwater has not been accurately quantified and the influencing factors of groundwater level dynamics during the freezing-thawing period remain unclear. Reasonable representation of this process on the field scale is very important for improving our understanding of water budgets during the freezing-thawing cycle. In this study, we investigated the main factors controlling groundwater level fluctuations during the freezing-thawing period at two sites in Northeast China through comparative analyses of long-term field observations of air temperature, precipitation, snow depth, liquid soil water content, soil water temperature, and fluctuations of groundwater level. We found that the seasonal variations in groundwater table coincided with the soil frost freezing-thawing seasonal cycle, which exhibited a “V” shape. Freezing-induced groundwater decline occurred only when the maximum depth of effect of freezing and thawing overlapped with the maximum height of capillary rise in unconfined groundwater. Moreover, the decline was controlled by air temperature, snow cover, soil media properties, and soil water distribution. By comparing the change trends of groundwater level and calculating the water budget, the process of the rise of groundwater level could be further divided into three stages, during which groundwater was recharged by frost melt water and snowmelt water. Among them, snowmelt water had a limited contribution, accounting for less than 20% of the total recharge. The results have potential applications in the development of reasonable water-management plans for irrigation, using which soil salt can be washed out and suitable soil thermal and moisture conditions can be maintained for winter crops or farming in the next year.

Effect of mechanical damage on the quality characteristics of banana fruits during short-term storage

Fresh fruits like bananas are very susceptible to mechanical damage during postharvest handling which can result in a substantial decline in quality. The study aims to evaluate the effect of bruise damage and storage temperatures on the quality of banana fruits after 48 h storage. Each ‘Grand Naine’ banana fruit was impacted once by using a drop impact test using three different heights (10, 30, and 50 cm) and storage temperatures (13 and 22 °C) after 48 h of storage. Different quality analyses were measured like bruise measurements (impact energy, bruise area, bruise volume, and bruise susceptibility), weight loss, total soluble solids (TSS), color (L*, a*, b*, hue°, chroma, yellowness index, yellowness value) headspace gases (respiration and ethylene production rate). The results showed that bruise measurements (bruise area, bruise volume, and bruise susceptibility) were highly affected by drop height. The quality parameters like weight, color, total soluble solids and headspace gases were affected by drop height and storage condition. Weight loss, total soluble solids, respiration rate, and ethylene production rate increased as drop height and storage temperature rise. Storage at ambient conditions (22 °C) accelerated bruising occurrence in banana fruits. Fewer changes were observed after 48 h of storage. The least value of yellowness index was observed on the non-bruised banana fruits (84.03) under 13 °C storage conditions. The findings of the study can provide baseline data to understand the mechanical damage mechanism on fruit quality, hoping to create awareness and educate farming communities and consumers. Storage temperature management is another approach that needs to be followed to reduce the occurrence of mechanical damage in fresh produce.

Interfacial Bonding Strength in Cement Mortar Beams Reinforced with Metamaterial Bars

Reinforced concrete beam (RCB) elements show low mechanical performance when interfacial bonding strength (IBS) is not well controlled. New tailorable material-structure arrangements - Metamaterials - offer solutions to the IBS problem. This paper analyzes the mechanical characteristics of IBS on RCBs for reinforced cement mortar containing Metamaterial bars (MMB) that were machined from SAE 1020 Carbon steel. Each MMB has a stepped geometrical shape, with a cylindrical bar divided into equal-length segments, along with a ’rise height’ (p) change. Four geometries were defined, i.e., R0− Smooth bar, R1− p = 0.1mm, R2− p =0.3mm and R3− p=0.5mm. Three-point flexural strength tests were performed on the RCBs to determine the maximum bond strength (ML) between the MMB and cement mortar. Images of interfacial regions were obtained using SEM and 3D Roughness Reconstruction software to calculate the average roughness (Ra) and the roughness height (Rz). The reinforcement MMB geometry had a significant impact on the ML results, particularly on the first crack strength and the failure mode. The R3 geometry ML values were higher than the other tested geometries (44.5%). The results of the scale models are encouraging and offer a novel and prospective direction for further experimental and even numerical Metamaterial research to improve interfacial bond strength.

Effect of outrigger systems for tall buildings

The development of tall building construction is increasing worldwide today to meet the demands and challenges in construction industry. The intention of tall building construction is owing to population growth and lack of enough horizontal spaces. The rise in height of the tall building needs at most care on lateral stiffness of the structure where the introduction of outrigger trusses plays a vital role. In this paper, an investigation has been performed to study the behaviour of outrigger trusses on different locations of the building using response spectrum analysis. For this analysis, a three-dimensional building model is developed for G + 20, G + 26 and G + 30 storey RC building to find out the performance of outrigger trusses subjected to earthquake loading conditions. The performance analysis is evaluated by ETABS software and the analysis results were compared among lateral displacements, storey shear and storey drift to find out optimal position of outriggers and an efficient reduction of storey drift in a structure. It was observed that, the introduction of outrigger trusses at the bottom storey reduces considerable drift to enhance the stiffness of the structure.

ПОВЫШЕНИЕ ПРОХОДИМОСТИ МНОГООПОРНЫХ ДОЖДЕВАЛЬНЫХ МАШИН

Studies have found that standard circular irrigation sprinklers installed on multi-support sprinklers cause the formation of a deep track on the field, which increases the power to move the machine, leads to bogies slipping and a decrease in machine performance. It is proposed to install sector nozzles or near-surface sprinkler devices with contour irrigation nozzles on the pipeline of the "Frigate" sprinkler machines in the area of the trolleys, which reduce and exclude the ingress of irrigation water under the wheels of the trolleys. For electrified truss sprinkler machines, two variants of near-surface sprinkling devices have been developed, which are installed on the water outlets closest to the trolleys and on the short pipes of the trolleys. Devices of near-surface sprinkling have the ability to adjust the height of the installation of sprinkler nozzles from 1.5 to 3 m above the soil surface, which reduces the height of the rain cloud rise by 0.5-1.5 m from the surface of plants. The wind load is reduced and the flight time of raindrops is reduced, which increases the uniformity of watering in the wind and reduces water losses for evaporation and demolition. The use of near-surface sprinkling devices in the area of trolleys with contour (sector) irrigation nozzles reduces the depth of the track by the end of the irrigation season from 25-30 cm to 7-12 cm and increases the productivity of sprinkler machines, tractor units and harvesting equipment.

Effect of 21 June 2020 solar eclipse on the ionosphere using VLF and GPS observations and modeling

A solar eclipse event provides a great opportunity to examine the behavioral concept of the ionospheric electron density (N e ) variability in the low latitude region. The current work presents our outcomes from the simultaneous assessment of Tweeks (radio atmospherics) and radio signals (fixed frequency of the transmitter's signal) from multifarious VLF transmitters observed at Varanasi (Geog. Lat. 25.27 0 N, Geog. Long. 82.98 0 E, Geomag. Lat. 14 0 55′N). To find the presence of disturbances in the ionosphere Global Positioning System (GPS) data at Hyderabad (geog. lat. 17 0 20 / N, long. 78 0 30 / E) and Bangalore (geog. lat. 12 0 58 / N, long. 77 0 33 / E) is also analyzed during the period of the solar eclipse on 21 June 2020. As the Sun was eclipsed, the nighttime phenomenon of ‘Tweeks' was also observed in the daytime through the annular solar eclipse due to nighttime conditions as the solar disc was dusked. Tweek analysis shows the variation in the ionospheric reflection heights (∼8–11 km) and electron density (∼3–2 cm −3 ) in the D-region during the eclipse. The reflection height of the D-region ionosphere increases from ∼84 km and goes to ∼95 km and then decreases to ∼87 km. Electron concentration (electron density) decreased throughout the eclipse from 24 cm −3 to 21 cm −3 and then increases to 23 cm −3 . Eclipse-imposed modifications in VLF transmitter’s (HWU and NWC) signals displays an average change (decrease) of 2.8 dB and 0.8 dB in the signal strength of 18.3 kHz (HWU) and 19.8 kHz (NWC) transmitters respectively and a rise in virtual reference height (H′) and sharpness factor (β), as compared with normal days. The de-trended value of total electron content (DTEC) variations at both stations clearly shows the presence of travelling ionospheric disturbances (TIDs) having wave-like features. The Fast Fourier Transform (FFT) analysis shows that periodicity at both the station lies in two regimes one belongs to a period between 20 and 50 min and the other belongs to 50–90 min indicating such oscillation observed in the ionosphere are induced by atmospheric gravity waves (AGWs) generated during the period of the solar eclipse.