Water Vapor Phase Research Articles

The Development and Atomic Structure of Zinc Oxide Crystals Grown within Polymers from Vapor Phase Precursors.

Sequential infiltration synthesis (SIS), also known as vapor phase infiltration (VPI), is a quickly expanding technique that allows growth of inorganic materials within polymers from vapor phase precursors. With an increasing materials library, which encompasses numerous organometallic precursors and polymer chemistries, and an expanding application space, the importance of understanding the mechanisms that govern SIS growth is ever increasing. In this work, we studied the growth of polycrystalline ZnO clusters and particles in three representative polymers: poly(methyl methacrylate), SU-8, and polymethacrolein using vapor phase diethyl zinc and water. Utilizing two atomic resolution methods, high-resolution scanning transmission electron microscopy and synchrotron X-ray absorption spectroscopy, we probed the evolution of ZnO nanocrystals size and crystallinity level inside the polymers with advancing cycles─from early nucleation and growth after a single cycle, through the formation of nanometric particles within the films, and to the coalescence of the particles upon polymer removal and thermal treatment. Through in situ Fourier transform infrared spectroscopy and microgravimetry, we highlight the important role of water molecules throughout the process and the polymers' hygroscopic level that leads to the observed differences in growth patterns between the polymers, in terms of particle size, dispersity, and the evolution of crystalline order. These insights expand our understanding of crystalline materials growth within polymers and enable rational design of hybrid materials and polymer-templated inorganic nanostructures.

Surface free energy calculation of the solid–fluid interfaces from molecular simulation

In this work, I present a straightforward approach for computing surface free energy γF based on the assessment of surface internal energy (γU), avoiding the difficulty connected to the determination of the elastic contribution in the case of a solid surface. This methodology has thus been extended to the calculation of γF for the interface between the liquid–vapor phase of water, the solid–vapor interface of aluminum, the aluminum–water interface, rigid graphene–water solid–liquid interfaces, and the n-dodecane–water liquid–liquid interface.

Study on the coupling mechanism of water-heat-vapor-salt-mechanics in unsaturated freezing sulfate saline soil

Understanding the internal regularity of unsaturated freezing sulfate saline soil is of utmost importance concerning the durability and stability of cold region engineering in sulfate saline soil areas. One-sided freezing experiments were performed on unsaturated sulfate saline soils with varying salt and moisture contents and temperature gradients to investigate the interplay of water-vapor-salt migration, heat transfer, ice-water and water-vapor phase transformations, salt crystallization, and salt-frost heave. This study presented a novel water-heat-vapor-salt-mechanics coupling model that considers water-vapor-salt migration and its feedback on soil deformation. The results signify that the water accumulation at the top surface of unsaturated freezing sulfate saline soil is primarily due to water vapor migration. Water-vapor-salt migration, ice-water phase transition, and salt crystallization form more ice and salt crystals, filling the air-filled pores and causing significant salt-frost heave. Water vapor transfer and accumulation further exacerbate the soil deformation for unsaturated freezing sulfate saline soil. The calculating results agree with the test data and demonstrate the efficacy of the proposed five-field coupling model. These findings hold significant implications for developing practical solutions for mitigating the negative impacts of salt-frost heave induced by water-vapor-salt transfer in unsaturated freezing sulfate saline soil on construction projects.

Study on condensation of oily particles under the influence of water vapor phase transition

To address the problem that oily fine particles are too small to be easily captured by traditional dust removal equipment, which hinders improving the purification efficiency, this paper proposes using the technical principle of water vapor phase transition to conduct experiments and simulations. A set of water vapor experimental devices for fine particles of oil mist is designed, and the data are analyzed by a Grimm spectrometer. The experimental results show the phase change of water vapor has a remarkable effect on the agglomeration of oily fine particles. Phase change condensation makes the particle size of fine particles increase by 5–10 times in a truly brief time, and the polymerization and removal efficiency are greatly improved. To analyze the changes of the coalescence characteristics in a larger range of parameter changes, the Euler multiphase flow model is adopted, the particle condensation growth rate function is introduced by a user-defined function to establish a coalescence model and the heterogeneous condensation growth characteristics of oily particles are analyzed in a supersaturated water vapor environment. The simulation results show that the condensing chamber temperature of the condensing chamber is 283 K, and the lower the air flow rate of the condensing chamber, the more favorable the heterogeneous condensation growth of oil particles. The change rule of agglomeration characteristics of oily particles obtained by experiment and simulation proves the feasibility of improving the removal efficiency of oily fine particles.

Comprehensive analysis of shutdown purge influencing factors of proton exchange membrane fuel cell based on water heat transfer and water vapor phase change mechanism

A two-dimensional multiphase proton exchange membrane fuel cell model is established to study the effect mechanism of temperature, pressure, humidity, and flow rate on the purge rate and ionomer dissolved water content at the end of purging on the basis of water heat transfer and water vapor phase change mechanism. The numerical model is analyzed by COMSOL Multiphysics 6.0 software, and the polarization curve and high-frequency impedance curve obtained under the same operating conditions are used to verify the validity of the model. Results show that ionomer dissolved water content increases and then decreases slightly due to the liquid water dissolved phase transfer in the slow-change step of the purge. Temperature, pressure, and humidity can effectively improve the purge rate and reduce the ionomer dissolved water content of the purge end. However, flow rate has little impact on both, but it can shorten the duration of the first stage and improve the effectiveness of the purge by effectively removing liquid water. This study provides a basis for revealing the influence of shutdown purge and formulating a reasonable shutdown purge strategy.

Microcracking of strawberry fruit cuticles: mechanism and factors

Microscopic cracks in the cuticle (microcracks) are the first symptom of the strawberry fruit disorder ‘water soaking’ in which the fruit surface appears watery, translucent, and pale. Water soaking severely impacts fruit quality. The objective was to investigate the factors and mechanisms of cuticular microcracking in strawberry. Fluorescence microscopy revealed numerous microcracks in the achene depressions, on the rims between depressions and at the bases of trichomes. Microcracks in the achene depressions and on the rims were either parallel or transversely oriented relative to a radius drawn from the rim to the point of attachment of the achene. In the achene depression, the frequency of microcracks with parallel orientation decreased from the calyx end of the fruit, towards the fruit tip, while the frequency of those with transverse orientation remained constant. Most microcracks occurred above the periclinal cell walls of the epidermal cells. The long axes of the epidermal cells were primarily parallel-oriented. Microcracking increased during fruit development. Cuticle mass per fruit remained constant as fruit surface area increased but cuticle thickness decreased. When fruit developed under high relative humidity (RH) conditions, the cuticle had more microcracks than under low RH conditions. Exposing the fruit surface to increasing RHs, increased microcracking, especially above 75% RH. Liquid-phase water on the fruit surface was markedly more effective in inducing microcracking than high vapor-phase water (high RH). The results demonstrate that a combination of surface area growth strain and water exposure is causal in inducing microcracking of the strawberry cuticle.

Carbon gain is coordinated with enhanced stomatal conductance and hydraulic architecture in coffee plants acclimated to elevated [CO2]: The interplay with irradiance supply

We recently demonstrated that, under elevated [CO2] (eCa), coffee (Coffea arabica L.) plants grown at high light (HL), but not at low light (LL), display higher stomatal conductance (gs) than at ambient [CO2] (aCa). We then hypothesized that the enhanced gs at eCa/HL, if sustained at the long-term, would lead to adjustments in hydraulic architecture. To test this hypothesis, potted plants of coffee were grown in open-top chambers for 12 months under HL or LL (ca. 9 or 1 mol photons m−2 day−1, respectively); these light treatments were combined with two [CO2] levels (ca. 437 or 705 μmol mol−1, respectively). Under eCa/HL, increased gs was closely accompanied by increases in branch and leaf hydraulic conductances, suggesting a coordinated response between liquid- and vapor-phase water flows throughout the plant. Still under HL, eCa also resulted in increased Huber value (sapwood area-to-total leaf area), sapwood area-to-stem diameter, and root mass-to-total leaf area, thus further improving the water supply to the leaves. Our results demonstrate that Ca is a central player in coffee physiology increasing carbon gain through a close association between stomatal function and an improved hydraulic architecture under HL conditions.

Modeling of multi-phase, multi-fluid flows with applications to marine hydrokinetic turbines

In this paper, a numerical formulation for modeling turbulent multi-phase, multi-fluid flows over real-life marine devices is presented. The flow field is governed by the Navier–Stokes equations with an Arbitrary-Lagrangian–Eulerian (ALE) description of the continuum for handling independent domain movements. The multi-phase phenomenon is modeled for an iso-thermal homogeneous mixture of water vapor and liquid phases using a transport equation for the vapor volume fraction. The multi-fluid phenomenon is modeled using the level-set method where a geometric function, namely, the signed distance function (SDF) describes the level-set field. Turbulence modeling is handled in the context of the variational multiscale (VMS) method resulting in an ALE-VMS formulation for multi-phase, multi-fluid flows over moving hydrodynamic objects. Several augmentations to the formulation are discussed in this paper including the sliding interface (SI) operator and its role in enforcing the compatibility of solution fields between in-contact computational subdomains during the different steps of the solution. This formulation is validated against experimental data for a real-life horizontal-axis marine turbine under different flow conditions including single-phase flows, multi-phase flows and multi-fluid flows. The performance of the turbine as well as the expected flow behaviors are compared to the experimental data with success. An additional case is simulated for a multi-phase, multi-fluid flow condition showing the capabilities and robustness of the presented numerical formulation.

Thermodynamic Study of the Electric Field Effect on Liquid-Vapor Mixture at Equilibrium: An Analysis on a Water-Ethanol Mixture.

In this paper, the effect of electric fields on phase equilibria through polarization is investigated. A relation is derived for the chemical potential of a system, where the electric field is localized over a liquid phase mixture in equilibrium with a vapor phase mixture. This relation is then applied to a water-ethanol mixture to explore the effect of polarization-based electric fields on the liquid phase composition. It is observed that the quadratic dependence on electric field strength produces little effect below field strengths of approx. 10 MV/m. However, above this field strength, the mole fraction of water in the liquid phase grows rapidly, increasing by a factor of 8 for a water vapor phase fraction of 0.2 and a field strength of 500 MV/m, which approaches the dielectric breakdown strength of water. Nonetheless, this field strength could be achievable with microfluidic experimental setups.

A ReaxFF-based molecular dynamics study of the destruction of PFAS due to ultrasound

This work uses a computational approach to provide a mechanistic explanation for the experimentally observed destruction of per- and polyfluoroalkyl substances (PFAS) in water due to ultrasound. The PFAS compounds have caused a strong public and regulatory response due to their ubiquitous presence in the environment and toxicity to humans. In this research, ReaxFF -based Molecular Dynamics simulation under several temperatures ranging from 373 K to 5,000 K and different environments such as water vapor, O2, N2, and air were performed to understand the mechanism of PFAS destruction. The simulation results showed greater than 98% PFAS degradation was observed within 8 ns under a temperature of 5,000 K in a water vapor phase, replicating the observed micro/nano bubbles implosion and PFAS destruction during the application of ultrasound. Additionally, the manuscript discusses the reaction pathways and how PFAS degradation evolves providing a mechanistic basis for the destruction of PFAS in water due to ultrasound. The simulation showed that small chain molecules C1 and C2 fluoro-radical products are the most dominant species over the simulated period and are the impediment to an efficient degradation of PFAS. Furthermore, this research confirms the empirical findings observations that the mineralization of PFAS molecules occurs without the generation of byproducts. These findings highlight the potential of virtual experiments in complementing laboratory experiments and theoretical projections to enhance the understanding of PFAS mineralization during the application of ultrasound.

Long-wave infrared laser-induced breakdown spectroscopy of complex gas molecules in the vicinity of a laser-induced plasma.

Vibration-rotation signatures of intact water and complex organic molecules in vapor phase were detected, identified, and mode-assigned in the long-wave infrared emissions of laser-induced plasma. Time resolved long-wave infrared emissions were also studied to assess the temporal behaviors of these gaseous molecular emitters. The temperatures of these molecular vapors in the hot and transient vapor-plasma plume of the laser-induced plasma were estimated to be well above room temperatures during their existence. The temperatures of the water vapors in the vapor-plasma plume were found to be evolving with time and ranging from>2700K at 10µs to∼1500K at 200µs after plasma initiations using HITRAN/HAPI based molecular spectral analysis. The observations in the present study comprise (to our knowledge) the first direct evidence of hot water and intact complex organic gas molecules in the vicinity of the laser-induced plasma. The findings presented in this work serve as an important step forward in improving the understanding of the thermodynamic characteristics (such as temperatures and phases) of intact complex molecules in a hot and intricate system such as the vapor-plasma plume of a laser-induced plasma, which is essential in both fundamental studies of plasmas and of laser-induced plasma based analytical applications.

The effects of four different solvent vapours on the restoration of obliterated stamp markings from five different wooden surfaces

The stamp markings on wooden surfaces, which are placed on trees and products including antiques, indicate the status of trees and involve identifying data regarding the products. Such markings are obliterated either to facilitate illegal logging or to conceal product information. Despite the wide literature on the restoration of obliterated characters on metal and polymer surfaces, the recovery of defaced characters on wooden surfaces appears to be understudied. Several reference texts in the forensic marks’ examination literature suggest that water, water vapor, and alkaline solutions are useful in restoring the abraded markings on the wood. Since there does not seem to be any experimental study proving such success, this study aimed to fill this gap. This study conducted experimental research by using water, ethanol, ammonia, and chloroform to recover the scraped characters on samples obtained from walnut, beech, spruce, oak, and cedar trees. The cold-stamped characters, which were defaced at varying depths, were restored using vapor and liquid phases of four solvents. While the vapor phases of water, ethanol, and ammonia yielded good outcomes on all types of wooden surfaces, the liquid phases did not seem to be useful in the revisualization process. The response of the vapors, which varied between 62 and 220 s, depended on the type of wood. The restoration technique developed in this research offers the possibility of on-site usage, easy application, utilization of low-cost solvents, rapid recovery, and effectiveness on various wooden surfaces. Overall, the restoration methodology used in this research appears to be fruitful in retrieving identifying information on wooden samples.

Mutual independence of water and n-nonane nucleation at low temperatures.

The interaction of water with different substances in the earth's atmosphere lies at the heart of many processes that influence our climate. However, it is still unclear how different species interact with water on the molecular level and in which ways this interaction contributes to the water vapor phase transition. Here, we report the first measurements of water-nonane binary nucleation in the 50-110K temperature range, along with unary nucleation data of both. The time-dependent cluster size distribution in a uniform post-nozzle flow was measured by time-of-flight mass spectrometry coupled with single-photon ionization. From these data, we extract experimental rates and rate constants for both nucleation and cluster growth. The observed mass spectra of water/nonane clusters are not or only slightly affected by the introduction of the other vapor, and the formation of mixed clusters was not observed during nucleation of the mixed vapor. Additionally, the nucleation rate of either substance is not much affected by the presence (or absence) of the other species, i.e., the nucleation of water and nonane proceeds independently, indicating that hetero-molecular clusters do not play a role during nucleation. Only at the lowest temperature of our experiment (i.e., 51K) do the measurements suggest that interspecies interaction slows water cluster growth. The findings here are in contrast to our earlier work in which we showed that vapor components in other mixtures, e.g., CO2 and toluene/H2O, can interact to promote nucleation and cluster growth in a similar temperature range.

The effect of relative humidity on vapor dispersion of liquefied natural gas: A CFD simulation using three phase change models

LNG is stored in cryogenic conditions, where the temperature is under 111K. In case of an accidental leakage into a normal atmosphere, LNG will vaporize and form cold methane gas cloud, namely LNG vapor cloud. In the existing researches, few have studied the effect of the inevitable water vapor phase change on the dilution of LNG vapor cloud under different relative humidity conditions. In this paper, a two-phase multi-species model is used in combination with three common water phase change treatments to simulate the dispersion of LNG vapor cloud and analyze the effect of relative humidity on it. The three approaches to deal with water phase transfer are: the one neglecting water phase change, and the other two considering water phase change by using the Lee model and the Sun model respectively. It is found that the results obtained by the Lee model and the Sun model show a similar response to humidity. In addition, although the density of LNG vapor clouds is usually higher than that of the surrounding air, there is a chance for the ambient air to overweigh the LNG vapor cloud in a hot and rather wet setting (RH>80%) if water phase transfer is considered.

Experimental and Numerical Investigation on Infilled Vertical Well LASER-Assisted SAGD

In the SAGD process with dual horizontal wells in heterogeneous reservoirs, the injection pressure of steam huff-n-puff by infilled interwell vertical wells is too high, and the heat communication between SAGD wellpairs and infilled wells is too long, which leads to a series of problems. The solvent-assisted vertical well stimulation (LASER) technology is proposed to solve the problems above. The solvent formula was optimized, and its key mechanism was studied by viscosity reduction experiments, multicomponent phase behavior experiments at high temperature and high pressure, and scaled two-dimensional physical experiments. The experimental results show that when adding 10% 2# or 3# solvent oil, the viscosity reduction of crude oil can reach 96.65% and 96.73%, respectively. The HTHP visualized phase behavior experiment results show that the mixture of low flash point solvent oil 2# with high flash point solvent oil 3# (volumetric ratio 3 : 2) has excellent high temperature oil solubility stability and is similar to water vapor phase behavior, so it is determined as the ideal formula. The scaled two-dimensional physical experiment results show that the solvent-assisted vertical well huff-n-puff has the key mechanism of reducing injection pressure and porous flow resistance, expanding the sweep region of injected fluid and accelerating thermal communication. The cycle of huff-n-puff was reduced from 6 to 3, which greatly shortened the thermal communication time. From the scaled physical experiments, the oil rate and the oil recovery of SAGD were improved by 19.86% and 6.3%, respectively. Field-scale numerical simulation was performed, and the production performance compared with SAGD and conventional infilled CSS-SAGD was investigated, which shows that by adding solvent into steam stimulation, 6 cycles were reduced, and the incremental oil recovery factor was 27.3% and 13.2%, respectively. The performance of accelerating thermal communication and production improvement by LASER has been validated by 4 SAGD wellpairs in field practice, and its long-term prediction result shows significant potential in similar heterogeneous SAGD reservoirs.

Thermal conductivity analysis of ceramic membranes for recovering water from flue gas

Condensation is the common mechanism of water intake from gases. Transport membrane condenser is a newly proposed technology to recover water from flue gas based on the mechanism of condensation. Most of the existing heat transfer research on transport membrane condenser focuses on water vapor phase change or fluid convection heat transfer, and there is a lack of research on the thermal conductivity of ceramic membranes. The significance of studying thermal conductivity is to optimize the overall heat transfer performance. The thermal conductivity of alumina ceramic solid materials is not good enough, which can affect the industrial application performance to a certain extent. There is currently a lack of experimental measurements or theoretical calculations to quantitatively characterize the thermal conductivity of ceramic membranes. This affects the optimization of overall heat transfer performance of transport membrane condenser. In this paper, coal fly ash is used as the raw materials to prepare macroporous ceramic membranes. Coal fly ash is a very cheap material. It can greatly reduce the manufacturing cost of transport membrane condenser using coal fly ash to prepare ceramic membranes. The classical theoretical model of thermal conductivity of porous materials is introduced, the calculation and experimental results are compared, and the validity and limitation of the classical models in analyzing the heat transfer problem of transport membrane condenser are discussed. Finally, based on the composite effective medium theory, combining with the experimental results, a modified model is proposed. The modified model reduces the average theoretical error to 7.20%, and enriches the research on the heat transfer theory of transport membrane condenser.

Performance of Some Novel Mixed Solvents as Entrainers for Separation of Water and Acetonitrile

Performance of some novel mixed solvents as entrainers was tested for acetonitrile dehydration by extractive distillation. The mixed solvents are composed of ethylene glycol (EG) and choline chloride (ChCl) (EG + ChCl 8:1, EG + ChCl 4:1, EG + ChCl 2:1, and EG + ChCl 4:3), ethylene glycol (EG) and glycerol (EG + glycerol 1:1, EG + glycerol 1:2, EG + glycerol 1:4, and EG + glycerol 1:6), and dimethyl sulfoxide (DMSO) and ChCl (DMSO + ChCl 14:1). Isobaric vapor–liquid equilibrium (VLE) data were measured at 101.3 kPa and at a solvent-free acetonitrile mole fraction of 0.95 for the quaternary systems of water + acetonitrile + EG + ChCl, water + acetonitrile + EG + glycerol, and water + acetonitrile + DMSO + ChCl and for the ternary system of water + acetonitrile + DMSO. The NRTL equation was used for the correlation of the experimental VLE data. For all the three quaternary systems and one ternary system, the mean absolute deviations of equilibrium temperature were no more than 0.33 K, and the mean absolute deviations of water and acetonitrile vapor phase mole fractions were no more than 0.0026 and 0.0047, respectively. The mixed solvent EG + ChCl 4:3, which is also a deep eutectic solvent, showed favorable solvent performance. The azeotrope of water + acetonitrile can be removed at a solvent mass fraction of 0.212 or a solvent mole fraction of 0.104. This amount is less than that of EG (0.367 in mass fraction and 0.227 in mole fraction), EG + glycerol 1:6 (0.341 in mass fraction and 0.195 in mole fraction), and DMSO + ChCl 14:1 (0.266 in mass fraction and 0.153 in mole fraction).

Modelling approach to predict the fire-related heat transfer in porous gypsum based on multi-phase simulations including water vapour transport, phase change and radiative heat transfer

The heat transfer in gypsum exposed to fire is significantly affected by heat conduction, mass transfer and condensation/evaporation effects of water vapour in the porous structure. In the past, numerical models to predict the heat transfer in gypsum were mainly limited to heat conduction and mass transfer of water vapour in thin gypsum boards used in wall assemblies. Thus, in the present study a multi-phase approach is proposed to predict the heat transfer within gypsum under fire exposure including conduction, mass transfer and condensation/evaporation. The consideration of water vapour transport and its condensation in the porous structure was leading to a good prediction of the heating process of gypsum up to approx. 100 °C. Furthermore, the calculated temperatures above 100 °C were adequate up to 2 cm from the fire side. However, at a higher distance from the fire the additional implementation of a thermal radiation model was crucial to improve the heat transfer in gypsum. Including the thermal radiation, the proposed numerical model is able to calculate the temperatures in the gypsum blocks in close accordance to the measurement. • Fire resistance test of gypsum and measurement of the temperature profile. • Lee model to predict evaporation/condensation of water in porous gypsum. • Multi-phase approach for the water vapour transport through gypsum in fire tests. • Thermal radiation modelling in porous gypsum with discrete ordinates model (DOM). • Porosity-corrected DO modelling was successfully used for radiation in gypsum.

Optimization of Condenser Backwash Method to Maintain Condenser Performance During the Backwash Process in PLTGU Grati

The condenser is a device used to change the water vapor phase that has been used to rotate the turbine blade into a liquid phase by condensing it. When the condenser tube is dirty, it can disrupt the steam condensation process which affects the efficiency of the condenser. To overcome this problem a condenser backwash is carried out.  Condenser backwash has a good influence on unit efficiency but backwash activities also reduce production by decreasing vacuum condensers and steam turbine loads. When the vacuum condenser backwash process decreases + - 24 mmHg and the steam turbine load decreases + - 8 MW.The condenser backwash process is carried out from the control room with the observation of parameters from the local area or equipment. Backwash condensers are done one by one as needed. The condenser type in PLTGU Grati Block I is a type of crossflow with two sides, namely, side A and side B. Each side of the condenser has a different sequence backwash condition. This study will be carried out a backwash method that is different from the sequence of automatic sequences.In the normal condenser backwash activity of data table 3 we can know there is a decrease in steam turbine load ± 8MW and a decrease in vacuum ± 24 mmHg. This is because at a certain period the condenser performance is reduced because at the time of switching valve one side of the condenser is not irrigated by seawater so that the heat transfer in the condenser is reduced which has an impact on a load of steam turbine and vacuum condenser. After the research was obtained that the greater the opening of the valve inlet when the condenser backwash then the decrease in vacuum and steam turbine load decreased even no decrease in load.The backwash method that can be done to keep the vacuum condenser and steam turbine load stable is by maneuvering the valve inlet, outlet, and condenser backwash valve. The results of the analysis obtained were a more stable decrease in steam turbine production in 0 MW and a decrease in the vacuum of 14 mmHg.

Transparent Anti-SARS-CoV-2 and Antibacterial Silver Oxide Coatings.

Transparent antimicrobial coatings can maintain the aesthetic appeal of surfaces and the functionality of a touch-screen while adding the benefit of reducing disease transmission. We fabricated an antimicrobial coating of silver oxide particles in a silicate matrix on glass. The matrix was grown by a modified Stöber sol–gel process with vapor-phase water and ammonia. A coating on glass with 2.4 mg of Ag2O per mm2 caused a reduction of 99.3% of SARS-CoV-2 and >99.5% of Pseudomonas aeruginosa, Staphylococcus aureus, and methicillin-resistant Staphylococcus aureus compared to the uncoated glass after 1 h. We envisage that screen protectors with transparent antimicrobial coatings will find particular application to communal touch-screens, such as in supermarkets and other check-out or check-in facilities where a number of individuals utilize the same touch-screen in a short interval.