Glass Tube Research Articles

Locomotor Activity of Adult Olive Fruit Flies Recorded under Conditions of Food or Water Deprivation

The olive fruit fly, known as Bactrocera oleae (Rossi) (Diptera: Tephritidae), is causing substantial economic losses in olive crops worldwide. Studying the activity patterns of the insect may expand our knowledge to eventually adopt more sustainable and effective pest control approaches. In the present study, we investigated the impact of food and water deprivation on the mobility of olive fruit flies using a modified version of the LAM25 system (locomotor activity monitor)—Trikinetics, an automated locomotor activity electronic device. Both male and female flies at four different age groups, reared on olives in the laboratory, were individually placed in glass tubes. Their locomotor activity was recorded every minute by three monitors within the digital device over a three-day period. Our observations revealed that adults exhibited significantly reduced movement during nighttime compared to daytime. The greatest mobility was observed during the period of 15:00 to 20:59. Additionally, younger flies demonstrated higher levels of mobility compared to older ones. Flies subjected to both food and water deprivation exhibited higher mobility compared to the control group. These insights offer valuable insights for enhancing pest management strategies aimed at controlling olive fruit flies adopting a more sustainable approach.

An experimental study of dynamic flashing in a square tube using tap water

Flashing is a pressure driven phase change phenomenon. It is widely studied due to its richness in physics and applications such as in desalination, in nuclear industry to name a few. Dynamic flashing is a situation wherein the pressure drop for flashing is initiated through the flow of liquid. A recently developed novel desalination system [1] utilizes combined dynamic flashing and vapor separation through tangential injection for producing potable water. An understanding of dynamic flashing in a tube with reference to the novel desalination system could help with its optimization. In this work, dynamic flashing of tap water occurring in a clear quartz square tube was studied. The pressure and temperature measurements along the tube were made and analyzed for different inlet flowrates and initial liquid temperatures. The pressure and temperature values showed increasing gradients along the tube indicating increased vapor production or flashing for increasing flowrates and initial liquid temperatures. The vapor production from flashing and the resulting flow regimes along the tube were tracked and identified through high-speed imaging. Visual observations showed complex flow regimes with bubbles nucleating and growing throughout the tube due to flashing. Most of the bubble formation was observed in the bulk with little nucleation on the glass tube wall. Void fraction measurements along the tube based on capacitance impedance technique were performed to supplement the visual observations which showed increasing void fraction along the tube matching the observed flow regimes from vapor production.

Capillary-based, multifunctional manipulation of particles and fluids via focused surface acoustic waves

Surface acoustic wave (SAW)-enabled acoustofluidic technologies have recently attracted increasing attention for applications in biology, chemistry, biophysics, and medicine. Most SAW acoustofluidic devices generate acoustic energy which is then transmitted into custom microfabricated polymer-based channels. There are limited studies on delivering this acoustic energy into convenient commercially-available glass tubes for manipulating particles and fluids. Herein, we have constructed a capillary-based SAW acoustofluidic device for multifunctional fluidic and particle manipulation. This device integrates a converging interdigitated transducer to generate focused SAWs on a piezoelectric chip, as well as a glass capillary that transports particles and fluids. To understand the actuation mechanisms underlying this device, we performed finite element simulations by considering piezoelectric, solid mechanic, and pressure acoustic physics. This experimental study shows that the capillary-based SAW acoustofluidic device can perform multiple functions including enriching particles, patterning particles, transporting particles and fluids, as well as generating droplets with controlled sizes. Given the usefulness of these functions, we expect that this acoustofluidic device can be useful in applications such as pharmaceutical manufacturing, biofabrication, and bioanalysis.

The Effect of Insulation Thickness on Heat Transfer Characteristics and Flammability in Tube Mesoscale Combustors

Micropower generator is a micro-scale energy source that has two main components, namely a micro/mesoscale combustor and thermophotovoltaics (TPV). The micro-scale combustor is one part that functions as a combustion chamber that produces heat in micropower plants. Heptane is used as fuel, while the combustor combustion chamber with a diameter of 3.5 mm is made from duraluminium-quart glass tube. Combustion stability in the combustion chamber is influenced by several factors, such as temperature, geometry, and combustion chamber design. In order to maintain flame stability, mesh is added to the combustion chamber. One way to minimize heat loss in the combustion chamber is to add an insulating layer to the combustion chamber. This research aims to prove the role of adding an insulating layer in flame stability in mesoscale burners. It is necessary to add an appropriate insulating layer to minimize heat loss so that it remains stable in the mesoscale burner. This experimental test shows that the temperature distribution when adding an insulation layer with a thickness of 3 mm has a higher temperature on the outside compared to a thickness of 6 mm. Meanwhile, the temperature inside the combustor chamber with a thickness of 6 mm is superior to that with a thickness of 3 mm. The flame limit of the combustor with a mesh distance of 5 mm for liquid heptane fuel was successfully stable at an equivalent ratio of ɸ0.97 – 1.5 with a maximum speed of 31.7.

Graphite counter electrode modified Tropaeolin‐O photo‐sensitized photogalvanic cells for solar power and storage

AbstractAn optimization, photo‐stability, and hysteresis property of the Graphite counter electrode‐modified Tropaeolin‐O (TPO) photo‐sensitized photogalvanic (PG) cells has been investigated. A complex H‐shaped cell design, a costly and delicate saturated calomel electrode (counter electrode), and a heavy sensitizer molecule (dye having high molecular weight, low diffusivity, and low photo‐stability) have been exploited for fabricating most of the PG cells so far. All these factors are not suitable for the fabrication of durable and cheap PG cells. Therefore, in the present study, the highly conductive/catalytically active robust graphite electrode with TPO dye photosensitizer (having a low molecular weight, higher diffusivity, and higher photo‐stability) has been exploited with diffusion‐friendly low cost and a simple transparent cylindrical glass tube. The cheap and robust graphite counter electrode has been exploited for optimization and long‐term study of the TPO photo‐sensitized PG cells. The observed electrical output is potential 676 mV, current 2000 µA, and power 340.0 μW. The power, current, and efficiency, have been found quite independent of the illumination window size. The potential and current have been observed to be quite stable over a long time during illumination, and the same has been supported by the hysteresis study.

Micrococcal nuclease regulates biofilm formation and dispersal in methicillin-resistant Staphylococcus aureus USA300.

Biofilm formation is an important virulence factor for methicillin-resistant Staphylococcus aureus (MRSA). The extracellular matrix of MRSA biofilms contains significant amounts of double-stranded DNA that hold the biofilm together. MRSA cells secrete micrococcal nuclease (Nuc1), which degrades double-stranded DNA. In this study, we used standard methodologies to investigate the role of Nuc1 in MRSA biofilm formation and dispersal. We quantified biofilm formation and extracellular DNA (eDNA) levels in broth and agar cultures. In some experiments, cultures were supplemented with sub-MIC amoxicillin to induce biofilm formation. Biofilm erosion was quantitated by culturing biofilms on rods and enumerating detached colony-forming units (CFUs), and biofilm sloughing was investigated by perfusing biofilms cultured in glass tubes with fresh broth and measuring the sizes of the detached cell aggregates. We found that an MRSA nuc1- mutant strain produced significantly more biofilm and more eDNA than a wild-type strain, both in the absence and presence of sub-MIC amoxicillin. nuc1- mutant biofilms grown on rods detached significantly less than wild-type biofilms. Detachment was restored by exogenous DNase or complementing the nuc1- mutant. In the sloughing assay, nuc1- mutant biofilms released cell aggregates that were significantly larger than those released by wild-type biofilms. Our results suggest that Nuc1 modulates biofilm formation, biofilm detachment, and the sizes of detached cell aggregates. These processes may play a role in the spread and subsequent survival of MRSA biofilms during biofilm-related infections.IMPORTANCEInfections caused by antibiotic-resistant bacteria known as methicillin-resistant Staphylococcus aureus (MRSA) are a significant problem in hospitals. MRSA forms adherent biofilms on implanted medical devices such as catheters and breathing tubes. Bacteria can detach from biofilms on these devices and spread to other parts of the body such as the blood or lungs, where they can cause life-threatening infections. In this article, researchers show that MRSA secretes an enzyme known as thermonuclease that causes bacteria to detach from the biofilm. This is important because understanding the mechanism by which MRSA detaches from biofilms could lead to the development of procedures to mitigate the problem.

Surface recombination in Pyrex in oxygen DC glow discharges: mesoscopic modelling and comparison with experiments

Surface recombination in an oxygen DC glow discharge in a Pyrex (borosilicate glass) tube is studied via mesoscopic modelling and comparison with measurements of recombination probability. A total of 106 experimental conditions are assessed, with discharge current varying between 10 and 40 mA, pressure values ranging between 0.75 and 10 Torr, and fixed outer wall temperatures ( Tw ) of −20, 5, 25 and 50∘C . The model includes O+O and O+O2 surface recombination reactions and a Tw dependent desorption frequency. The model is validated for all the 106 studied conditions and intends to have predictive capabilities. The analysis of the simulation results highlights that for Tw=−20∘C and Tw=5∘C the dominant recombination mechanisms involve physisorbed oxygen atoms ( OF ) in Langmuir–Hinshelwood (L-H) recombination OF+OF and in Eley–Rideal (E-R) recombination O2+OF , while for Tw=25∘C and Tw=50∘C processes involving chemisorbed oxygen atoms ( OS ) in E-R O+OS and L-H OF+OS also play a relevant role. A discussion is taken on the relevant recombination mechanisms and on ozone wall production, with relevance for higher pressure regimes.

Poly-β-(1→6)-N-acetyl-D-glucosamine mediates surface attachment, biofilm formation, and biocide resistance in Cutibacterium acnes.

The commensal skin bacterium Cutibacterium acnes plays a role in the pathogenesis of acne vulgaris and also causes opportunistic infections of implanted medical devices due to its ability to form biofilms on biomaterial surfaces. Poly-β-(1→6)-N-acetyl-D-glucosamine (PNAG) is an extracellular polysaccharide that mediates biofilm formation and biocide resistance in a wide range of bacterial pathogens. The objective of this study was to determine whether C. acnes produces PNAG, and whether PNAG contributes to C. acnes biofilm formation and biocide resistance in vitro. PNAG was detected on the surface of C. acnes cells by fluorescence confocal microscopy using the antigen-specific human IgG1 monoclonal antibody F598. PNAG was detected in C. acnes biofilms by measuring the ability of the PNAG-specific glycosidase dispersin B to inhibit biofilm formation and sensitize biofilms to biocide killing. Monoclonal antibody F598 bound to the surface of C. acnes cells. Dispersin B inhibited attachment of C. acnes cells to polystyrene rods, inhibited biofilm formation by C. acnes in glass and polypropylene tubes, and sensitized C. acnes biofilms to killing by benzoyl peroxide and tetracycline. C. acnes produces PNAG, and PNAG contributes to C. acnes biofilm formation and biocide resistance in vitro. PNAG may play a role in C. acnes skin colonization, biocide resistance, and virulence in vivo.

Time-resolved observation of 150 kHz high-power pulse burst high-frequency discharge using a high-speed video camera and an intensified charge coupled device camera

The discharge phase and time evolution of a 150 kHz high-power pulse burst discharge were observed. A vacuum chamber was constructed by connecting glass tubes on which a solenoid coil was wound. Burst pulses with a width of 1000 μs and a repetition rate of 10 Hz were applied to the solenoid coil. A high-speed video camera and an intensified CCD camera were used to record photographs of the discharges. Observation of the discharge phase using a high-speed camera showed that the discharge occurs at the time of 40 μs and propagates from the wall of the cylindrical reactor. Over time, the discharge pattern evolves, and a branched pattern appears. The number of the branches changes with time. The discharge blinks synchronize with the instantaneous power, which suggests that the discharge is generated and maintained by the electrostatic field generated by the sides of the coil. The propagation velocity calculated from downstream decreases with increasing pressure and increases with increasing power.

A Comparative Analysis of Field Electron Emission from Carbon Black Embedded within Insulated Copper Hollowed Wires and Glass Tubes

A Comparative Analysis of Field Electron Emission from Carbon Black Embedded within Insulated Copper Hollowed Wires and Glass Tubes

Label- and Reagent-Free Optical Sensor for Absorption-Based Detection of Urea Concentration in Water Solutions.

Contactless and label-free detection of urea content in aqueous solutions is of great interest in chemical, biomedical, industrial, and automotive applications. In this work, we demonstrate a compact and low-cost instrumental configuration for label-free, reagent-free, and contactless detection of urea dissolved in water, which exploits the absorption properties of urea in the near-infrared wavelength region. The intensity of the radiation transmitted through the fluid under test, contained in a rectangle hollow glass tubing with an optical pathlength of 1 mm, is detected in two spectral bands. Two low-cost, low-power LEDs with emission spectra centered at λ = 1450 nm and λ = 2350 nm are used as readout sources. The photodetector is positioned on the other side of the tubing, in front of the LEDs. The detection performances of a photodiode and of a thermal optical power detector have been compared, exploiting different approaches for LED driving current modulation and photodetected signal processing. The implemented detection system has been tested on urea-water solutions with urea concentrations from 0 up to 525 mg/mL as well as on two samples of commercial diesel exhaust fluid ("AdBlue™"). Considering the transmitted intensity in presence of the urea-water solution, at λ = 1450 nm and λ = 2350 nm, normalized to the transmitted intensity in presence of water, we demonstrate that their ratio is linearly related to urea concentration on a wide range and with good sensitivity.

Design of solar thermal absorption air conditioning system using CO2 with synthetic building load

Traditional air conditioning and refrigeration solutions rely on compressor-driven systems, leading to increased electricity consumption and intensified greenhouse gas (GHG) emissions. These systems primarily utilize synthetic refrigerants such as CFCs, HCFCs, and HFCs. Despite their advantages, these refrigerants are either banned or subject to restricted permissions under the Montreal Protocol (1987) and the Kyoto Protocol (1997) due to environmental concerns. According to the Paris Accord, ratified by 196 parties as of 2017, there is a global shift towards low global warming refrigerants and eco-friendly alternatives. COP27 reaffirmed global commitments to limit temperature rise to 1.5 °C, emphasizing urgent action and stronger climate plans to combat global warming. CO2 envisaged by ASHRAE is resurrected as a promising natural refrigerant with the advent of high-pressure technologies the design employs a solar evacuated glass tube collector (EGTC) with U-shaped copper tubes and flat plate collector (FPC) to harness solar thermal energy. An immersed heat exchanger's (HX) based thermal storage tank is incorporated to address the intermittency of solar energy. The CO2 refrigerant offers advantages over other natural refrigerants due to its low critical point.This research conducts a TRNSYS® simulation of a 35.2 kW absorption cooling system with synthetic building load driven by energy captured through FPC and EGTC using R-744, additionally supported by a supplementary boiler for traditional office timing. The system design comprises two solar collectors, the EGTC and FPC, integrated with two different cooling loop configurations (C1 and C2). In C1, the hot water that exits the generator of the absorption chiller is forwarded toward the immersed HX-based hot storage tank, which is connected to the solar and absorption cooling loop. In C2, the working fluid leaving the absorption chiller is diverted directly toward the auxiliary boiler/furnace, if the temperature in the storage tank falls below the necessary level (108.89 °C) and if the tank temperature is greater than this set point temperature, then the flow passes through the storage tank. Both system designs have been developed using TRNSYS, with dynamic simulations conducted throughout the summer.The solar fraction and collector efficiency are considered as key performance indicators to evaluate and compare the system's effectiveness. Then the optimization of system parameters is performed for all four cases (EGTC C1 & C2 and FPC C1 & C2) based on these key performance indicators, all configurations integrated with a fixed synthetic building cooling load. The optimum parameters are found for all four cases, and the optimum parameters for EGTC C1 & C2 are 100 m2, 4 m3, and 11° for collector area, storage tank volume, and collector slope respectively. Similarly, for FPC based configurations, these parameters are 200 m2, 32 m3 for C2 and 4 m3 for C1, and 20° respectively. The results revealed better C2 performance than C1, with EGTC outperforming FPC. The final results were computed for the EGTC based designs due to their high solar fractions, with EGTC C2 emerging as the optimal configuration, achieving a seasonal solar fraction of 0.649.

Preparation and evaluation of microcapsules of sodium alginate based on microfluidic technology

Many active ingredients in food products are destroyed by gastric acids and enzymes as they pass through the stomach, thereby reducing the desired effect of the target ingredient. In addition, traditional microcapsule preparation methods usually break up the dispersion by mechanical stirring or oscillation, which generates droplets of uneven size and inconsistent inclusion content, and mechanical external forces may cause denaturation and inactivation of active substances. This study aimed to use microfluidics to generate Oil-in-water-in-oil (O/W/O) droplet structures with good monodispersity and highly tunable properties, and to further prepare microcapsules with high encapsulation rate and targeted intestinal release by taking advantage of the cross-linking properties of alginate that reacts with Ca2+ under acidic conditions. Finally, the particle size distribution, release effect, encapsulation effect and oxidative stability of the core-shell microcapsules were evaluated. In this study, two types of microcapsules, homogeneous and core-shell microcapsules, were prepared by selecting tea polyphenols and vitamin E as models for hydrophilic and lipophilic bioactive compounds, respectively. Thin shell microcapsules with a shell thickness of about 25 μm were prepared using PDMS chip conditioning. Large microcapsules with a particle size of 230 μm were generated by using capillary glass tube chips, which had an excellent antioxidant property with a retention rate of 88.66 ± 1.25% of VE after 20 days of storage at 4 °C, while all of the VE was oxidized in the bare environment. In addition, in simulated gastric fluid, the release of VE was only about 20%, while in artificial intestinal fluid, the release was close to 100%, so the microcapsules also had intestinal targeting properties.

Transient Phenomena of Dynamic Contact Angle in Micro Capillary Flows

This study is devoted to investigating the dynamics of liquid driven by capillary force in a circular tube. A microscope was used to visualize the meniscus movement and the contact angle. The experiments were carried out with glycerin–water mixtures with viscosity ranging from 0.21 to 1.36 Pa∙s by filling the test liquid in a borosilicate glass tube with an inner diameter of 200 μm. The wetting distances of the meniscus with time were compared with the theoretical solution by considering the dynamic variation of contact angle. The results show that the theoretical solution agrees well with experimental data due to the reflection of the actual dynamic contact angle for the transient motions in the developing entrance region. In view of momentum balance, variations of dominant force according to the time were determined by separated inertial periods, such as inertial, inertial-viscous, and viscous time stages.

Efficient arabinoxylan assay for wheat: Exploring variability and molecular marker associations in Wholemeal and refined flour

In this study, we present a modified high throughput phloroglucinol colorimetric assay for the quantification of arabinoxylans (AX) in wheat named PentoQuant. The method was downscaled from a 10 ml glass tube to 2 ml microcentrifuge tube format, resulting in a fivefold increase in throughput while concurrently reducing the overall cost and manual labor required for the analysis. Comparison with established colorimetric assays and gas chromatography validates the modified protocol, demonstrating its superior repeatability, rapidity, and simplicity. The effectiveness of the protocol was tested on 606 unique whole meal (WM) and refined flour (RF) bread wheat samples which revealed the presence of more than a twofold variation in both the soluble (WE-AX) and total (TOT-AX) AX fractions in WM (TOT-AX = 31.9–76.1 mg/g; WE-AX = 4.4–12.6 mg/g) and RF (TOT-AX = 7.7–22.4 mg/g; WE-AX = 3.9–11.4 mg/g). Results obtained from the AX quantification were used to test the effectiveness of four molecular markers associated with AX variation and targeting two major genomic regions on the 1BL and 6BS chromosomes. These markers appeared to be particularly relevant for the WE-AX fraction, providing insights to enable marker-assisted breeding.

Effect of target material on electrical properties of a two-electrode dielectric barrier helium plasma jet

In this paper we present electrical characterization of a dielectric barrier discharge plasma jet operating with He (2 slm and 3 slm) as working gas and interacting with Cu, polyethylene terephthalate and distilled H2O targets. We used a plasma jet with two copper electrodes wrapped around a glass tube. One electrode was powered by a high-voltage sinusoidal signal of 30 kHz, whereas the other electrode and the target holder were grounded. We have performed detailed investigation of the voltage and current waveforms, phase differences, volt–current (V–I) characteristics, calculated impedances and power deposition. The aim was to determine the influence of different target materials and their conductivity on the plasma properties. We calculated the total harmonic distortion factor that showed that the current through grounded electrode depends on the conductivity of the target. We also calculated the power delivered to the plasma core and the plasma plume regions and observed that the change in the target conductance influenced the power in both plasma regions. The experimentally characterized electrical circuit was simulated by a model of equivalent electrical circuit corresponding to the plasma-off and plasma-on regime. Voltage controlled current source was added as model of a streamer formed in plasma-on regime.

Experimental analysis of subcooled flow boiling in a microchannel evaporator of a pumped two-phase loop

High-power electronics exceed the heat dissipation capability of conventional air or liquid-based forced convection cooling systems. A pumped two-phase loop (P2PL) utilizing phase change heat transfer can effectively transport and dissipate high heat fluxes generated from the electronics at very small thermal resistance while consuming negligible pumping power. Existing research primarily focuses on standalone evaporators with fixed boundary conditions, neglecting the interactions between the evaporator and other components within the P2PL. This knowledge gap hinders the comprehensive understanding of system performance. To address this need, an experimental study was conducted to examine subcooled flow boiling in a microchannel evaporator of P2PL using R-134a. The parameters used for the investigation are evaporator heat input, mass flux, chiller loop inlet temperature, and fluid charge ratio. Additionally, flow visualization through a sight glass tube at the evaporator outlet was used to identify the two-phase flow regimes, namely – the onset of nucleate boiling, bubbly, slug, stratified, annular, and mist flow. The dominant flow boiling mechanisms and its transitions in the microchannel were identified based on the varying slopes of the boiling curves. The dynamic responses were additionally utilized to differentiate between single-phase and two-phase flows as well as to identify the propagation of dryout in the microchannel evaporator. The study further revealed that for a constant wall superheat, within the convective boiling dominant regime, the heat transfer rate in the evaporator exhibits an increase with the mass flow rate. In contrast, in the nucleate boiling dominant regime, the heat transfer rate remains unaffected by the mass flow rate. Furthermore, it was found that as the fluid charge ratio increases, the heat transfer coefficient and pressure drop in the evaporator decreases.

Directional vapor mobility from asymmetric microstructured surfaces in an adverse gravity orientation

Stagnant vapor growth on a downward-facing flat surface leads to increased surface temperature and dryout at relatively low heat fluxes. The current study investigates boiling from a surface with periodic 60°-30° or 75°-15° asymmetric sawtooth microstructures to passively remove vapor slugs in adverse gravity. Bubble dynamics is experimentally investigated in an 8-mm square borosilicate glass tube and visualized using a high-speed camera to measure vapor bubble morphology and velocity in the FC-72 dielectric liquid. The vapor bubble's morphology is observed to change based on its relative size to the ratchets. This change manifests as a decrease in the curvature ratio between the crest and trough of the microstructure as the vapor bubble gets larger. The pattern of vapor slugs nucleating from intended, engineered sites, coalescing to form larger slugs that slide across the microstructure, is observed at different frequencies at different heat fluxes. The microstructure supports increased vapor volume at higher heat fluxes, suggesting that a passive and self-regulating thermal management solution for adverse gravity applications is feasible. An empirical force balance model is developed based on the curvature-induced Young-Laplace pressure difference and retarding forces due to drag and buoyancy. The interplay between these forces is analyzed at different liquid film thicknesses, and the force balance is compared with a 75°-15° sawtooth structure. For a vapor slug spanning four sawteeth, the 75°-15° structure supported a 54 % increase in the feasible liquid film thickness range due to the increased long slope area.

Gravimetric and Thermal-Imaging Characterization of Water-Free Reflux Condensers for Laboratory Applications.

Water-free reflux condensers, which use convective cooling from the surrounding air to condense vapors, avoid the need for cooling water, which is more sustainable than water-cooled condensers, and eliminates the risk of flooding, but these devices are newer and less familiar to many chemists, who may never have used them before. To facilitate the shift to water-free condensers, several types of water-free condensers (simple glass tube, Vigreux column, Condensyn, Findenser, and air-cooled Dimroth) were characterized using three different solvents (ethyl acetate, acetone, and tetrahydrofuran) under both gentle and vigorous refluxing conditions to compare their relative performance and determine the condensing capacity/failure point. In addition to experimentally quantifying the performance of each condenser both gravimetrically and via infrared thermal imaging, energy-balance models were developed to gain insight into which factors were most important in driving their performance. Several of the water-free condensers, including the Findenser, Condensyn, and air-cooled Dimroth condenser, were shown to provide suitable performance for most refluxing operations.

Synthesis and Characterization of Vanadium Doped Hexagonal Rubidium Tungsten Bronze

Attempts have been made to synthesize vanadium doped rubidium hexagonal tungsten bronzes with the nominal composition RbxVyW1-yO3 (x = 0.30, 0.25, and 0.0 ≤ y ≤ x). The samples were synthesized using the solid state synthesis method in a silica glass tube under vacuum at (10-2 Torr) 700°C. The X-ray diffraction measurements reveal that a pure hexagonal tungsten bronze (HTB) phase can be formed with a 60% replacement of W5+ by V5+. The systematic incorporation of vanadium into the HTB lattice, as well as the reduction of V/W-O bond lengths in the xy plane and the lengthening of these bonds in the crystallographic c direction, are also revealed by Rietveld structure refinement of XRD data. The XRD results are supported by FTIR absorption spectra of the oxidized phases. Furthermore, an absorption signature develops as a function of y and exhibits a considerable increase in intensity with the eventual replacement of W5+ by V5+, showing a large decrease in the metallic like contribution and revealing the compounds' nonmetallic nature. Elemental analysis indicates good agreement with nominal values, demonstrating that vanadium was systematically incorporated into the RbxVyW1-yO3 system. Dhaka Univ. J. Sci. 72(1): 77-84, 2024 (January)