Experimental investigation on the characteristics of the shock wave emitted by the cavitation bubble near the air bubble.

This study explores the mitigation of cavitation damage in hydraulic engineering through air entrainment. The primary aim is to experimentally analyze the shock wave characteristics emitted by cavitation bubbles adjacent to air bubbles affixed to a tube nozzle. The schlieren optical system is utilized to visualize the shock wave, while a hydrophone measures its pressure. Experiments are conducted on cavitation bubbles induced by the spark-generated method in the vicinity of air bubbles, varying the dimensionless distances and sizes of the air bubbles. The results indicate that (1) The introduction of an air bubble noticeably changes the morphology, kinematic behavior, and shock wave features of the cavitation bubble. (2) Four distinct shock wave patterns are identified based on the quantity and shape of the shock wave, with variations in the cavitation bubble's collapsing behavior and shock wave characteristics across different patterns. (3) The dimensionless distance γ and size δ exert significant influence on the shock wave's quantity, pressure peak, shape, and energy. With γ decreases or δ increases, the shock wave quantity increases while the shock wave intensity decreases. This investigation of the interaction between cavitation bubbles and air bubbles is essential for elucidating the mechanism through which air entrainment mitigates cavitation damage.

Numerical and experimental simulation on efficiency of air bubble barrier on various pollutants for preventing oil spill spread.

This study conducts experimental and numerical simulations and analyzes the effects of the air bubble barrier (ABB) on the oil spill spread prevention efficiency regarding the varying aperture diameter, air discharge, and pollutant type. In a computational fluid dynamics simulation, a multiphase flow is studied using the finite volume method with the volume of fluid technique in the Star CCM+ software. The pipe generating air bubbles is fixed at the bottom of the tank at 1.8 m from the side of the experimental setup. The distinctive points of the study are the experiments conducted on different pollutants and the utilization of a novel adjustable air nozzle positioned on the air feed pipe. The effectiveness of the ABB in mitigating the spread of marine pollution is contingent on the aperture size, air discharge, and pollutant type. This study demonstrates that the ABB's feasibility for preventing the oil spill spread has improved.

Air bubble artifact: why postmortem brain MRI should always be combined with postmortem CT.

Forensic pathology increasingly uses postmortem magnetic resonance imaging (PMMRI), particularly in pediatric cases. It should be noted that each (sudden and unexpected) death of an infant or child should have a forensic approach as well. Current postmortem imaging protocols do not focus adequately on forensic queries. First, it is important to demonstrate or rule out bleeding, especially in the brain. Thus, when incorporating PMMRI, a blood sensitive sequence (T2* and/or susceptibility weighted imaging (SWI)) should always be included. Secondly, as intracranial air might mimic small focal intracerebral hemorrhages, PMMRI should be preceded by postmortem CT (PMCT) since air is easily recognizable on CT. This will be illustrated by a case of a deceased 3-week-old baby. Finally, note that postmortem scans will often be interpreted by clinical radiologists, sometimes with no specific training, which makes this case report relevant for a broader audience.

Appearance and modeling of bubble artifacts in intracranial magnetic resonance-guided laser interstitial thermal therapy (MRg-LITT) temperature images.

PURPOSE: To understand if unexplained signal artifacts in MRg-LITT proton resonance frequency- (PRF-) shift thermometry images are caused by air bubbles or hemorrhages, and to characterize their effects on temperature measurements. METHODS: Retrospective image data from an IRB-approved clinical trial of intracranial MRg-LITT were inspected for asymmetric distortions observed in phase data during ablations, which have been previously reported as likely hemorrhages. A total of eight patient cases were selected: seven with artifact occurrence and one without. Mathematical image models for air bubbles or hemorrhages were implemented to estimate the size of the air bubble or hemorrhage needed to explain the clinically observed phase artifacts. Correlations and Bland-Altman analyses were used to determine if an air bubble model or a hemorrhage model was better correlated to the clinical data. The model was used to inject bubbles into clean PRF phase data without artifacts to examine how temperature profile distortions change with slice orientation. The simulated air-bubble injected data were compared to clinical data containing artifacts to examine the bubbles' effects on temperature and thermal damage estimates. RESULTS: The model demonstrated that air bubbles up to approximately 1 cm in diameter could explain the clinically observed phase artifacts. The bubble model predicts that a hemorrhage would have to be 2.2 times as large as an air bubble in order to explain the same extent of phase distortion observed in clinical data. Air bubbles had 16% percent higher correlations to the clinical PRF phase data than hemorrhages, even after rescaling the hemorrhage phases to better match the data. The air bubble model also explains how the phase artifacts lead to both large positive and large negative temperature errors, up to ±100 °C, which could cascade to damage estimate errors of several millimeters. CONCLUSION: Results showed that the artifacts are likely caused by air bubbles rather than hemorrhages, which may be introduced before heating or appear during heating. Manufacturers and users of devices that rely upon PRF-shift thermometry should be aware these phase distortions from bubble artifacts can result in large temperature errors.

Unexpected dosing errors due to air bubbles in infusion lines with and without air filters.

The effect of the presence of an air bubble, inside an infusion line, on the time (Tnew) needed for a new medication to reach the patient after a syringe exchange was studied in this paper. If an air bubble escapes through an air filter, then a sudden drop in pressure occurs, causing a relaxation of the compressible part of the syringe, followed by a gradual restoration of the flow rate in the line. We modeled this phenomenon mathematically and measured it experimentally in vitro. In an example with a pump flow rate of 5 mL/h and an air bubble of 1 cm length inside an infusion line (diameter 1 mm) with an air filter, both theory and experiment yield an additional increase of at least 600% in delay time if a naive estimate (based on the size of the bubble alone) is replaced by a more realistic estimate incorporating compressibility. Furthermore, we show that an air bubble in a line without air filter may increase Tnew by a factor 2, depending on the initial position of the air bubble. We conclude that an air bubble in an infusion line causes delays that may not be expected by health care professionals.

Effect of oil-based emulsion on air bubbles in the spray sheet produced through the air-induction nozzle.

BACKGROUND: The air-induction spray featured by air bubbles involved in the spray sheet has attracted great attention in applications of agricultural spray due to its advantages of alleviating spray drift and promoting deposition. The objective of the presented study is to deepen the understanding of the mechanism of the air-induction spray through elucidating the effect of sprayed liquid on characteristics of air bubbles in the spray sheet. RESULTS: The air bubbles with relatively large sizes are stable for a long time span. As velocity of the water spray increases from 6.85 m s-1 to 17.87 m s-1 , average size of the air bubbles decreases from 383.21 µm to 236.47 µm. With the introduction of organosilicone surfactant, the surface tension of the sprayed liquid decreases from 67.38 mN m-1 to 31.32 mN m-1 ; accordingly, average size of the bubbles decreases from 383.21 µm to 160.9 µm. Compared to aqueous solutions spray, the oil-based emulsion spray is responsible for relatively small average size of air bubbles as the surface tension and spray velocity are respectively similar. CONCLUSION: Low drainage rate of the bubble lamella contributes to high stability of large air bubbles. The decrease of the average size of air bubbles is responsible for small volumetric median diameter of oil-based emulsion spray compared with water spray. Besides the increase of the spray velocity and the decrease of the surface tension, the Marangoni effect caused by dynamics of oil droplets at air-liquid interface also contributes to the decrease of average size of air bubbles. © 2022 Society of Chemical Industry.

Air bubble removal: Wettability contrast enabled microfluidic interconnects.

The presence of air bubbles boosts the shear resistance and causes pressure fluctuation within fluid-perfused microchannels, resulting in possible cell damage and even malfunction of microfluidic devices. Eliminating air bubbles is especially challenging in microscale where the adhesive surface tension force is often dominant over other forces. Here, we present an air bubble removal strategy from a novel surface engineering perspective. A microfluidic port-to-port interconnect was fabricated by modifying the peripheral of the microfluidic ports superhydrophobic, while maintaining the inner polymer microchannels hydrophilic. Such a sharp wettability contrast enabled a preferential fluidic entrance into the easy-wetting microchannels over the non-wetting boundaries of the microfluidic ports, while simultaneously filtering out any incoming air bubbles owing to the existence of port-to-port gaps. This bubble-eliminating capability was consistently demonstrated at varying flow rates and liquid analytes. Compared to equipment-intensive techniques and porous membrane-venting strategies, our wettability contrast-governed strategy provides a simple yet effective route for eliminating air bubbles and simultaneously sealing microfluidic interconnects.

Assessment of Bone Microarchitecture in Fresh Cadaveric Human Femurs: What Could Be the Clinical Relevance of Ultra-High Field MRI.

MRI could be applied for bone microarchitecture assessment; however, this technique is still suffering from low resolution compared to the trabecular dimension. A clear comparative analysis between MRI and X-ray microcomputed tomography (µCT) regarding microarchitecture metrics is still lacking. In this study, we performed a comparative analysis between µCT and 7T MRI with the aim of assessing the image resolution effect on the accuracy of microarchitecture metrics. We also addressed the issue of air bubble artifacts in cadaveric bones. Three fresh cadaveric femur heads were scanned using 7T MRI and µCT at high resolution (0.051 mm). Samples were submitted to a vacuum procedure combined with vibration to reduce the volume of air bubbles. Trabecular interconnectivity, a new metric, and conventional histomorphometric parameters were quantified using MR images and compared to those derived from µCT at full resolution and downsized resolutions (0.102 and 0.153 mm). Correlations between bone morphology and mineral density (BMD) were evaluated. Air bubbles were reduced by 99.8% in 30 min, leaving partial volume effects as the only source of bias. Morphological parameters quantified with 7T MRI were not statistically different (p > 0.01) to those computed from µCT images, with error up to 8% for both bone volume fraction and trabecular spacing. No linear correlation was found between BMD and all morphological parameters except trabecular interconnectivity (R2 = 0.69 for 7T MRI-BMD). These results strongly suggest that 7T MRI could be of interest for in vivo bone microarchitecture assessment, providing additional information about bone health and quality.

Corneal Effect of Air Bubble After Phacoemulsification.

Objectives: The aim of the study was to investigate the effect of air bubble on the cornea at the end of the cataract surgery with phacoemulsification. Methods: This prospective and case-control study included 71 patients with air bubble injected into the anterior chamber at the end of the operation and 63 age-sex-matched control patients without air bubble. Endothelial cell density (ECD), coefficient of variation (CV), hexagonality rate (HEX), and central corneal thickness (CCT) measurements were taken using non-contact specular microscopy preoperatively and at 1-day, 1-week, and 1-month postoperatively. Results: No significant difference was determined between the groups preoperatively in respect of mean visual acuity, anterior chamber depth, ECD, CV, HEX, and CCT values (p>0.05). The intraoperative average ultrasound power, effective phaco time, and ultrasound time values were similar (p>0.05). The CCT value was lower in the study group than in the control group on post-operative day 1 (p=0.012), but similar at 1 week and 1 month (p=0.102, p=0.330, respectively). No significant difference was determined between the groups in mean visual acuity, anterior chamber reaction, ECD, CV, and HEX values at 1-day, 1-week, and 1-month postoperatively (p>0.05). Conclusion: Air bubble may be used as an alternative method to reduce corneal edema on the 1st post-operative day. According to the results, although air bubble has no detrimental effect, there is also seen to be no protective effect on the corneal endothelium.

Relación entre la ubicación de la burbuja de aire en la transferencia embrionaria y las tasas de implantación y gestación evolutiva / Relationship between air bubble location at embryo transfer and implantation and ongoing pregnancy rates

Resumen OBJETIVO: Evaluar la relación entre la ubicación de la burbuja de aire que contiene los embriones y las tasas de implantación y de gestación clínica. El secundario: estudiar la relación entre la posición de la punta de la cánula, el grosor endometrial y el desplazamiento de la burbuja con esos desenlaces reproductivos. MATERIALES Y MÉTODOS: Estudio retrospectivo, observacional y de análisis de imágenes ecográficas de transferencias de embrión único en estadio de blastocisto practicadas por un mismo especialista en la Fundación IVI, Valencia, España, entre septiembre de 2013 y febrero de 2021. Criterios de selección: grosor endometrial ≥ 6 mm en el último control ecográfico, ausencia de miomas, IMC menor de 30 kg/m2, transferencias atraumáticas efectuadas por el mismo especialista. En función de la ubicación de la burbuja de aire se establecieron tres grupos de estudio (alta: mayor de 0.98 cm, media: 0.98 a 1.44 cm y baja: mayor de 1.44 cm) y para evaluar la asociación entre las categorías se aplicó el cálculo de razón de momios (OR) e IC95%. RESULTADOS: Se estudiaron 342 transferencias de embrión único. La edad media de las pacientes fue 39.70 ± 4.5 años. La relación entre la distancia de la burbuja de aire al fondo uterino y la tasa de implantación fue de 61 ± 9% en el grupo de ubicación alta, 64 ± 9% en el grupo de ubicación media, y de 56 ± 1% en el grupo de ubicación baja (p = 0.437). No se observaron diferencias en la tasa de gestación evolutiva analizada mediante probabilidad de ocurrencia entre grupos, con frecuencias de 0.60 en comparación con 0.64 (OR: 1.42; IC95%: 0.83 a 2.44; p: 0.199) y en la ubicación alta con media, y frecuencias de 0.60 en comparación con 0.56 (OR: 1.22; IC95%: 0.72-2.08; p: 0.462) entre alta y baja. CONCLUSIONES: No se encontró asociación entre la ubicación de la burbuja y las tasas de implantación y de gestación evolutiva. El mayor desplazamiento de la burbuja se asoció con mayores tasas de gestación evolutiva.

Abstract OBJECTIVE: To evaluate the relationship between the location of the air bubble containing the embryos and the implantation and clinical gestation rates. Secondary: to study the relationship between the position of the cannula tip, the endometrial thickness and the displacement of the bubble with these reproductive outcomes. MATERIALS AND METHODS: Retrospective, observational, ultrasound image analysis study of single embryo transfers at blastocyst stage performed by the same specialist at the IVI Foundation, Valencia, Spain, between September 2013 and February 2021. Selection criteria: endometrial thickness ≥ 6 mm at the last ultrasound control, absence of fibroids, BMI less than 30 kg/m2, atraumatic transfers, performed by the same specialist. Based on the location of the air bubble, three study groups were established (high: greater than 0.98 cm, medium: 0.98 to 1.44 cm and low: greater than 1.44 cm) and the odds ratio (OR) and 95%CI were used to evaluate the association between the categories. RESULTS: A total of 342 single embryo transfers were studied. The mean age of the patients was 39.70 ± 4.5 years. The relationship between the distance of the air bubble to the uterine fundus and the implantation rate was 61 ± 9% in the high placement group, 64 ± 9% in the medium placement group, and 56 ± 1% in the low placement group (p = 0.437). No differences were observed in the evolutionary gestation rate analyzed by probability of occurrence between groups, with frequencies of 0.60 compared to 0.64 (OR: 1.42; 95%CI: 0.83 to 2.44; p: 0.199) and high to medium location, and frequencies of 0.60 compared to 0.56 (OR: 1.22; 95%CI: 0.72-2.08; p: 0.462) between high and low. CONCLUSIONS: No association was found between the air bubble localization and implantation or ongoing pregnancy rates. However, a greater displacement of the bubble was associated with higher ongoing pregnancy rates.

Cough-induced bubbles formation in the heart: Is it related with a poor prognosis?

In current practice, it is not well-known whether the development of air bubbles spontaneously in the heart during routine transthoracic echocardiography examination has a clinical consequence. Even though there have been published case reports regarding the formation of air bubbles due to iatrogenic reasons, we could not find a case of a patient demonstrating spontaneous air bubbles formation due to only coughing. Thus, in this report, we present a case of an adult patient who had unexpected air bubbles in the heart after coughing. Furthermore, the patient experienced a catastrophic cerebrovascular accident after diagnosing such an event in the same day. We thought that spontaneously occurring air bubbles in the heart might have resulted in cerebrovascular accident by passing through patent foramen ovale, which we have diagnosed after we had seen that the spontaneously occurred air bubbles had also appeared in left chambers. To our knowledge, this might be the first case of such a patient in the literature. .

Air Bubble Bridge-Based Bioinspired Underwater Adhesion.

Wet adhesion is greatly demanded in fields of wearable devices, wound dressings, and smart robotics. However, reusable, noninvasive and convenient adhesive pads in the liquid environment have remained a challenge. Here, a novel concept of underwater adhesion inspired by the diving beetle, which utilizes the air bubbles as an adhesive to realize nondestructive and repeatable adhesion working across a wide range of scales is shown. The mechanism of underwater bubble adhesion is revealed by the capillarity of air-bubble bridge, of which the property depends on the dynamic bubble contact angles and the gap distance. The design principle of the air bubble-based underwater adhesion is proposed and validated to tune the interfacial acting force by theoretical and experimental results. Finally, a strong, reusable surface adhesive based on air bubble bridges is demonstrated from macro- to microscales in applications of particle manipulation and particle self-assembly. This unique view of underwater bubble adhesion provides new ideas for broader applications.

Natural thymol-based ternary deep eutectic solvents: Application in air-bubble assisted-dispersive liquid-liquid microextraction for the analysis of tetracyclines in water.

Four new thymol-based ternary deep eutectic solvents were prepared and evaluated as the extractive phase in air-bubbles assisted dispersive liquid-liquid microextraction for extraction of tetracycline, doxycycline, and oxytetracycline from the water before high-performance liquid chromatography. The maximum extraction efficiencies were obtained using 400 µL of [choline chloride]:[thymol]:[nonanoic acid] in the molar ratio of 1:2:2 at pH = 5. The solvent was characterized by FTIR and NMR spectroscopy. The hydrophobicity of the deep eutectic solvent and its effect on the pH of water samples after mixing was also studied. Besides, the extraction efficiency of the ternary deep eutectic solvent was compared with that of two binary thymol-based deep eutectic solvents, including [choline chloride]:[thymol] and [thymol]:[nonanoic acid] at the same conditions. Under optimal conditions, limits of detection and quantification were 1.2-8.0 and 3.8-26.6 µg/L, respectively. The linear ranges were 18.2-500 µg/L for oxytetracycline, 26.6-500 µg/L for tetracycline, and 3.8-500 µg/L for doxycycline with the determination coefficients > 0.9912. Intra- and inter-day relative standard deviations were 1.2-3.8 and 7.7-11.2%, respectively. The developed method was applied to the analysis of tetracyclines in unspiked and spiked environmental water samples, and the obtained recoveries were 74.5-95.4% with relative standard deviations of 1.2-4.0%.

Bubbling tinnitus caused by change in head position.

Because the density of air is lower than the effusion, air bubbles can be passively moved by a head position change, causing a bubbling sound in the affected ear.

Pseudocavitation sign at chest CT scan due to COVID-19 pneumonia: A report of 5 cases and literature review.

Coronavirus disease 2019 (COVID-19) pneumonia computed tomography imaging features have been described in detail in many studies. The pseudocavitation sign has not been described in the previous COVID-19 studies. We present chest computed tomography scans of 5 reverse transcriptase-polymerase chain reaction positive patients with COVID-19 pneumonia who has bare areas among pulmonary infiltrates. All 5 also had previous scans with similarly sized low attenuated areas in the same location prior to the addition of pulmonary infiltrates. The pre-existing cystic changes had become remarkable due to the contrast around them after the pulmonary infiltrates added. Therefore, they should be termed as "pseodocavity" according to Fleischner Society glossary. Small air-containing spaces between pulmonary infiltrates have been termed in previous COVID-19 studies as a new sign called "round cystic changes/air bubble sign/vacuolar sign." We would like to draw attention that the vacuolar sign and the synonyms may be the pseudocavity sign that is due to pre-existing changes rather than a new defined sign.

A New Detection Chamber Design on Centrifugal Microfluidic Platform to Measure Hemoglobin of Whole Blood.

Undoubtedly, microfluidics has been a focal point of interdisciplinary science during the last two decades, resulting in many developments in this area. Centrifugal microfluidic platforms have good potential for use in point-of-care devices because they take advantage of some intrinsic forces, most notably centrifugal force, which obviates the need to any external driving forces. Herein, we introduce a newly designed detection chamber for use on microfluidic discs that can be employed as an absorbance readout step in cases where the final solution has a very low viscosity and surface tension. In such situations, our chamber easily eliminates the air bubbles from the final solution without any interruption. One microfluidic disc for measuring the hemoglobin concentration was designed and constructed to verify the correct functioning of this detection chamber. This disc measured the hemoglobin concentration of the blood samples via the HiCN method. Then, the hemoglobin concentration of 11 blood samples was quantified and compared with the clinic's data using the hemoglobin measurement disc, which included four hemoglobin measurement sets, and each set contained two inlets for the blood sample and the reagent, one two-part mixing chamber, and one bubble-free detection chamber. The measured values of the disc had good linearity and conformity compared with the clinic's data, and there were no air bubbles in the detection step. In this study, the standard deviation and the turnaround time were ± 0.51 g/dL and 68 s, respectively.

The synergistic effect of focused ultrasound and biophotonics to overcome the barrier of light transmittance in biological tissue.

Optical technology is a tool to diagnose and treat human diseases. Shallow penetration depth caused by the high optical scattering nature of biological tissues is a significant obstacle to utilizing light in the biomedical field. In this paper, light transmission enhancement in the rat brain induced by focused ultrasound (FUS) was observed and the cause of observed enhancement was analyzed. Both air bubbles and mechanical deformation generated by FUS were cited as the cause. The Monte Carlo simulation was performed to investigate effects on transmission by air bubbles and finite element method was also used to describe mechanical deformation induced by motions of acoustic particles. As a result, it was found that the mechanical deformation was more suitable to describe the transmission change according to the FUS pulse observed in the experiment.

Application of polyethylene air-bubble cushions to improve the shock absorption performance of Type I construction helmets for repeated impacts.

BACKGROUND: The use of helmets was considered to be one of the important prevention strategies employed on construction sites. The shock absorption performance of a construction (or industrial) helmet is its most important performance parameter. Industrial helmets will experience cumulative structural damage when being impacted repeatedly with impact magnitudes greater than its endurance limit. OBJECTIVE: The current study is to test if the shock absorption performance of Type I construction helmets subjected to repeated impacts can be improved by applying polyethylene air-bubble cushions to the helmet suspension system. METHODS: Drop impact tests were performed using a commercial drop tower test machine following the ANSI Z89.1 Type I drop impact protocol. Typical off-the-shelf Type I construction helmets were evaluated in the study. A 5 mm thick air-bubble cushioning liner was placed between the headform and the helmet to be tested. Helmets were impacted ten times at different drop heights from 0.61 to 1.73 m. The effects of the air-bubble cushioning liner on the helmets' shock absorption performance were evaluated by comparing the peak transmitted forces collected from the original off-the-shelf helmet samples to the helmets equipped with air-bubble cushioning liners. RESULTS: Our results showed that a typical Type I construction helmet can be subjected to repeated impacts with a magnitude less than 22 J (corresponding to a drop height 0.61 m) without compromising its shock absorption performance. In comparison, the same construction helmet, when equipped with an air-bubble cushioning liner, can be subjected to repeated impacts of a magnitude of 54 J (corresponding to a drop height 1.52 m) without compromising its shock absorption performance. CONCLUSIONS: The results indicate that the helmet's shock absorbing endurance limit has been increased by 145% with addition of an air-bubble cushioning liner.

Measuring of time-series concentrations of nutrients in surface waters using osmotic sampler with air bubble segmentation and preservative addition.

The analysis of time-series concentrations (CTS) is of great importance when investigating the biogeochemical processes of nutrients in aquatic environments. However, obtaining CTS of nutrients remains a challenge using current sampling techniques. In this study, a novel in situ sampler was constructed using reverse osmosis membrane (ROM) osmotic pumps (OP) (ROM-OP sampler), and was used to obtain the CTS of nutrients in surface waters. The sampler consisted of a sampling OP, sample storing coil, filter, bubble injection module, and preservative adding module. When deployed, the sampling OP continuously draws ambient water through the filter into the sample storing coil, while simultaneously the preservative adding module continuously delivers preservative (H2SO4 solution) into the water flow. The bubble injection module periodically injects air bubbles into the sample storing coil, to segment the sample and create time stamp indicators that allow the sample age to be defined. Upon retrieval, the sample segments in the coil are sequentially pumped out of the sample storing coil and transferred into different vials for further analysis. The sampler was applied to measure the CTS of various nutrients, including dissolved total nitrogen, dissolved total phosphorus, dissolved reactive phosphorus, and nitrate in a river over a 20 day period and in municipal sewage treatment plant effluent for a 36 h period. Results showed that the ROM-OP sampler successfully obtained CTS of nutrients, capturing nutrient variations at a high temporal resolution. This sampler is relatively low-cost (~USD 300), small in size, lightweight, robust and does not require an external power source, showing high promise as an effective and efficient tool for monitoring nutrient CTS in aquatic environments.

Movement of air bubbles under various liquids using bioinspired conical surfaces.

Gas bubbles are of interest in various applications. The study of their movement is of importance. Gas bubbles are typically formed under liquids. Movement of liquid droplets on bioinspired conical surfaces is known to be facilitated by the Laplace pressure gradient. These conical surfaces, with various wettabilities and shapes, can also be used to move gas bubbles. In this study, effect of various liquids on movement of air bubble under liquid was studied. It was found that liquids with high surface tension and high density are more efficient in moving air bubbles. High surface tension and higher density increases the Laplace pressure gradient force and the buoyancy force, respectively, which drive under liquid air bubbles.