Evaporation Process Research Articles

Three-Dimensional Double-Layer Multi-Stage Thermal Management Fabric for Solar Desalination.

Water scarcity is a serious threat to the survival and development of mankind. Interfacial solar steam generation (ISSG) can alleviate the global freshwater shortage by converting sustainable solar power into thermal energy for desalination. ISSG possesses many advantages such as high photothermal efficiency, robust durability, and environmental friendliness. However, conventional evaporators suffered from huge heat losses in the evaporation process due to the lack of efficient thermal management. Herein, hydrophilic Tencel yarn is applied to fabricate a three-dimensional double-layer fabric evaporator (DLE) with efficient multi-stage thermal management. DLE enables multiple solar absorptions, promotes cold evaporation, and optimizes thermal management. The airflow was utilized after structure engineering for enhanced energy evaporation efficiency. The evaporation rate can reach 2.86 kg·m-2·h-1 under 1 sun (1 kW·m-2), and 6.26 kg·m-2·h-1 at a wind speed of 3 m·s-1. After a long duration of outdoor operation, the average daily evaporation rate remains stable at over 8.9 kg·m-2, and the removal rate of metal ions in seawater reaches 99%. Overall, DLE with efficient and durable three-dimensional multi-stage thermal management exhibits excellent practicality for solar desalination.

Bioaerosol sampling and bioanalysis: Applicability of the next generation impactor for quantifying Legionella pneumophila in droplet aerosols by flow cytometry

Bioaerosol generation, sampling, and cultivation-independent quantification of pathogenic bacteria play a crucial role in studying dose-response effects of Legionella pneumophila. Here, the Next Generation Impactor (NGI), initially created for pharmaceutical inhaling studies, was assessed for its potential to sample airborne bioaerosols and to separate size-dependent wet droplets by incrementally increasing the airflow speed. This stainless-steel sampler was shown in this study to be suitable for sampling prior to cultivation-independent analysis of pathogen-containing bioaerosols using washable cups. The applicability was studied by quantifying the total and intact cell count of L. pneumophila by flow cytometry after being dispersed into a droplet aerosol. Our results demonstrate a high total sampling efficiency of 95.5% ± 11.8% despite a lower biological sampling efficiency of 59.7% ± 16.5% for dry aerosols. However, by elevating the relative humidity (RH) to 100% in a liquid aerosolization unit, the biological sampling efficiency increased to over 90% for L. pneumophila. More than 50% of the cells were found in stage 1 using the liquid aerosolization unit. In comparison, 80% of the cells were sampled in stages 4–6 at 30% RH. Specifically, while at 100% RH, the droplet size mattered, at 30% RH, the size distribution of dry particles, in this case L. pneumophila, was relevant due to evaporation processes, which explains the size differences. These findings indicate the potential of the NGI for further exploration and application in studying other aerosol-borne pathogens, especially concerning the size distribution of wet droplets, viability, or effect-based bioanalysis.

Long-term contributions of VOC sources and their link to ozone pollution in Bronx, New York City

Changes in energy and environmental policies along with changes in the energy markets of New York State over the past two decades, have spurred interest in evaluating their impacts on emissions from various energy generation sectors. This study focused on quantifying these effects on VOC (volatile organic compounds) emissions and their subsequent impacts on air quality within the New York City (NYC) metropolitan area. NYC is an EPA nonattainment region for ozone (O3) and likely is a VOC limited region. NYC has a complex coastal topography and meteorology with low-level jets and sea/bay/land breeze circulation associated with heat waves, leading to summertime O3 exceedances and formation of secondary organic aerosol (SOA). To date, no comprehensive source apportionment studies have been done to understand the contributions of local and long-range sources of VOCs in this area. This study applied an improved Positive Matrix Factorization (PMF) methodology designed to incorporate atmospheric dispersion and photochemical reaction losses of VOCs to provide improved apportionment results. Hourly measurements of VOCs were obtained from a Photochemical Assessment Monitoring Station located at an urban site in the Bronx from 2000 to 2021. The study further explores the role of VOC sources in O3 and SOA formation and leverages advanced machine learning tools, XGBoost and SHAP algorithms, to identify synergistic interactions between sources and provided VOC source impacts on ambient O3 concentrations. Isoprene demonstrated a substantial influence in the source contribution of the biogenic factor, emphasizing its role in O3 formation. Notable contributions from anthropogenic emissions, such as fuel evaporation and various industrial processes, along with significant traffic-related sources that likely contribute to SOA formation, underscore the combined impact of natural and human-made sources on O3 pollution. Findings of this study can assist regulatory agencies in developing appropriate policy and management initiatives to control O3 pollution in NYC.

Методические аспекты анализа факторов, влияющих на испарение газоконденсата при подводных выбросах

The process of evaporation of gas condensate during emergency blowout of an underwater well has been studied insufficiently. The influence of various factors on the size of the zone of intense evaporation of gas condensate during the blowout of a shallow gas condensate well requires detailed consideration. In this paper, the researchers, using mathematical modeling, have analyzed this effect for wells with parameters characteristic of the Russian Arctic region. They have performed the calculations using the SPILLMOD model and the Lagrangian element evolution model. A significant dependence of the gas outlet area size and the gas blowout size on the sea surface on the values of the gas plume involvement parameter in the model has been revealed, and at the same time a weak dependence of the size of the zone of intense evaporation of gas condensate on this parameter. The values of the mass flow rate of gas condensate in the discharge, as well as its fractional composition, have a noticeably greater effect.

Formulation, Design, Optimization, and Characterization of Novel Long-acting Injectable Dosage Form of Anti-psychotic Drug

Background: The current research aimed to create and analyze a new long-acting Brexpiprazole (BRX) injectable for successful anti-psychotic drug therapy in order to decrease dosage frequency and increase patient compliance. Systems for drug transport to particular body sites or regulating release rates with accuracy are known as drug delivery systems (DDS). By affixing the drug to a carrier particle like liposomes, nanoparticles, microspheres, etc., which modifies the drug's absorption and release properties, using carrier technology, drugs may be delivered in an intelligent manner. Methods: Utilizing Resomer RG 502 H and RESOMER® RG 752 H extended-release Polymer, Using a quasi-emulsion solvent diffusion, microspheres were made, and emulsification and solvent evaporation process. Results: The produced microspheres were assessed for stability tests, in vitro drug release, flow characteristics, and drug entrapment efficiency. FTIR experiments were used to establish how well the drug excipients worked together. The acarbose microspheres that were created had an 89.9 to 96.1 percent drug entrapment efficiency. The impact of factors like polymer content on medication release was studied. The Stability study of the formulation was carried out under different conditions, and data were established. Comparative pharmacokinetic studies between marketed oral formulation and Brexpirazole microsphere test formulations in Wistar/SD Rats were carried out and concluded. Conclusion: Brexpiprazole (BRX) novel long-acting injectable formulation, could be used effectively for the treatment of mentally challenged anti-psychotic patients worldwide.

Experimental study on concentrating characteristics during static flash of aqueous NaCl solution at different flash speeds

This experimental study explores the concentration characteristics of aqueous NaCl solution in static flash evaporation, focusing on the equilibrium mass and concentration, at different flash speeds (FS). An aqueous NaCl solution, with an initial concentration (mass fraction) of 0.15 to 0.26, was employed as the working fluid. The superheat varied from 1.49K to 54.9K, while the flash speeds were adjusted from 0.006s-1 to 0.53s-1. The study delineates the flash evaporation process into two regions based on the interplay of heat transfer and steam-carrying effects: one where both factors are co-dominant, and another where heat transfer is the primary controlling element. The results indicate that increasing the flash speed effectively raises the equilibrium concentration in the co-controlled region but has no impact in the region dominated solely by heat transfer. Furthermore, initial saturation conditions at various flash speeds to predict whether the flash evaporation process is occurring in the co-controlled or heat transfer-controlled region are proposed. Calculating method of equilibrium mass/concentration at different flash speeds was set up.

Structural analysis and optoelectronic applications of 2-aminopyrimidine with pimelic acid crystal

This study investigates the reaction between 2-aminopyrimidine and pimelic acid, resulting in the formation of a novel crystal. The crystals were obtained through slow evaporation process. These crystals underwent PXRD testing to establish their crystalline properties. The values of the unit cell parameters are confirmed through SXRD analysis. The FTIR technique is applied to detect different functional groups present in the title crystals. The UV-Visible spectrum is recorded to find the band gap energy. From the photoluminescence spectrum the emission is observed at 353nm. The mechanical strength of the material against deformation is studied using Vickers micro hardness tester and the material is stated as soft material. The dielectric behaviour of the crystal is studied using LCRZ meter.

Numerical study of bischofite precursor droplet evaporation and thermal decomposition for spray pyrolysis systems

Understanding the evaporation and decomposition process of bischofite precursor droplets in a pyrolysis furnace is the prerequisite for designing an efficient spray bischofite treatment facility. However, current research lacks guidance on this behavior. Here, it provided a new theoretical basis for understanding evaporation characteristics and decomposition behavior by introducing the Abramzon-Sirignano and kinetics models. In addition, the effects of ambient temperature and relative humidity on the evaporation characteristics of different precursors were analyzed. Meanwhile, the decomposition products and yield changes were studied in detail under different temperatures and times. The results show that the mass transfer coefficient and latent heat of vaporization have the most significant influence on droplet evaporation. To high recovery rate, the reaction temperature must be above 1125 °C. The current work can guide obtaining high magnesium oxide yield from waste bischofite in pyrolysis.

Construction of bilayer cellulose-based aerogel with salt-resistant design for efficient solar desalination and wastewater purification

Solar-driven interfacial evaporation (SDIE) technology, which utilizes green and renewable solar energy to produce clean water, has shown great potential in alleviating global water scarcity. However, practical applications still face numerous challenges, including salt crystallization precipitation and accumulation, low energy utilization, and complex preparation processes. Hence, We designed a vertically ordered porous bilayer aerogel based on nanofibrillated cellulose (NFC)/polyethyleneimine (PEI) with excellent salt resistance, light absorption and local thermal effects to achieve efficient solar steam generation. Specifically, the photothermal conversion layer (PCL) at the top had excellent light absorption and photothermal conversion efficiency by introducing graphene oxide (GO) as a highly efficient photothermal material. The water transport layer (WTL) at the bottom ensured a stable water supply to the evaporation layer by virtue of the vertical water transfer path and inherent hydrophilicity, and effectively prevented formation of salts in the evaporation area. In addition, the designed aerogel had a low thermal conductivity, which achieved effective thermal insulation and further enhanced the localized heating effect. This superhydrophilic bilayer aerogel achieved a high evaporation rate of 1.9596 kg m−2 h−1 and an energy conversion efficiency of 92.28% under one solar irradiation. It is noteworthy that evaporation process exhibited excellent stability during 8 h of continuous evaporation in 20 wt% brine and no salt accumulation was observed on the evaporated surface. In addition, the bilayer aerogel demonstrated excellent long-term stability and self-cleaning. Meanwhile, its excellent anti-contamination and wastewater treatment capabilities give SDIE technology a stable and continuous operation in practical applications, thus demonstrating significant application potential.

A low-Mach volume-of-fluid model for the evaporation of suspended droplets in buoyancy-driven flows

This study introduces a comprehensive numerical model capable of simulating the evaporation of suspended droplets under different gravity conditions. Unlike previous studies, this work provides a detailed description of the multicomponent evaporation process by integrating: (i) interface-resolved evaporation; (ii) suspension by the action of the surface tension force, and (iii) variable physical properties. The model effectively captures complex phenomena such as thermal expansion, natural convective fluxes, and liquid internal recirculation, which cannot be directly resolved using more widespread spherically-symmetric models. Validation against experimental data confirms the model’s accuracy in predicting the droplet evaporation dynamics, and its utility in resolving discrepancies between prior numerical simulations results and experimental data. The model was implemented in the Basilisk framework; both the code and the simulations setups are freely available on the Basilisk sandbox.

Effect of the inclination angles of the capillary tube on the natural evaporation of absolute ethanol

Microchannel heat transfer plays an important role in microelectronics technology for heat dissipation, due to its high efficiency and low heat transfer temperature difference and flow resistance. To underpin the fundamental understanding of this technology, the natural evaporation process of absolute ethanol in a capillary tube at inclination angles ranging from 0° to 90° was investigated experimentally by exploring a spectrum of properties, such as Marangoni flow patterns, evaporation rate, heat flux, and temperature distribution. We found that the morphology of the meniscus is similar under different inclination angles, but the liquid and the tube wall slip to varying degrees due to the pressure difference at the liquid–vapor interface during evaporation. Therefore, the force distribution of the meniscus interface is different, and the resultant force is Fmax(60°) > Fmax(0°) > Fmax(30°) > Fmax(90°). We found that the morphology of the meniscus is independent of the inclination angle when absolute ethanol evaporates naturally. And the evaporation rate, heat flux and temperature distribution of meniscus at the initial stage of evaporation follow the law of resultant force distribution. That is, when the inclination angle is 60°, the evaporation rate and heat flux reach the maximum, i.e. 1.64 μm/s and 10.96 W/cm2, respectively, and the temperature between the center of the meniscus and the wedge region reaches 1.5 ℃. We used μ-PIV to observe the Marangoni vortex morphology of the vertical section of the meniscus, and found that there are different degrees of deformation at different inclination angles. When the inclination angle is 90°, the Marangoni vortex structure is destroyed.

Dynamical Adsorption Behavior Prediction of Dried Tobacco Leaf Heterogeneous Interfaces through Simulation and Image Recognition Techniques.

The process of spraying water and flavorings on dry tobacco is an important factor in the industrial environment and product quality. Tobacco as a complex porous fiber material, the interfacial transfer process of water is complex. In this study, machine learning and image recognition techniques were utilized to quickly obtain the structural parameters of the tobacco surface and construct a cellular structure model of the tobacco surface. In situ observation of the droplet impact spreading process was carried out using a high-speed camera to explore the droplet dissipation dynamics on different surfaces. And the competing processes of droplet wetting and evaporation under the influence of surface microstructure were determined by combining experimental studies and finite element simulation calculations. Based on the characteristics of tobacco pore size distribution, the infiltration under gas-liquid two-phase action was transformed into single-phase flow transfer under capillary force, and the continuous droplet infiltration process was simulated. A parallel artificial membrane permeability measurement method of bionic tobacco waxy layer was constructed for the screening of spray dosing copenetrant. This study brings new insights into the wetting of porous fibrous materials and is important for exploring the wetting process and additive development process influenced by the microstructure.

Study on the automatic control method for evaporation treatment of wet flue gas desulfurization wastewater in power plants

ABSTRACT DRFNN is used to predict the evaporation state of wastewater, and incremental PID algorithm is combined to adjust the control quantity. By real-time monitoring the state and parameter changes of wastewater evaporation treatment process, online adjusting and optimizing the parameters of DRFNN and incremental PID, the automatic control of desulfurization wastewater evaporation treatment is completed. The experimental results show that this method can achieve more accurate and reliable automatic control, short control time, strong ability to deal with emergencies, and can converge to stability in a short time. This method can effectively reduce the number of early alarms and failures of the system and save maintenance costs. The IAE values of chloride ion (Cl) and mercury (Hg) in this method are 0.3558 and 0.3872, respectively, which proves that the difference between the actual output and the expected output of this method is very small, which proves that the system in this paper has high accuracy.

Effects of non-commutative geometry on black hole properties

In this study, we investigate the signatures of a non-commutative black hole solution. Initially, we calculate the thermodynamic properties of the system, including entropy, heat capacity, and Hawking radiation. For the latter quantity, we employ two distinct methods: surface gravity and the topological approach. Additionally, we examine the emission rate and remnant mass within this context. Remarkably, the lifetime of the black hole, after reaching its final state due to the evaporation process, is expressed analytically up to a grey-body factor. We estimate the lifetime for specific initial and final mass configurations. Also, we analyze the tensorial quasinormal modes using the 6th-order WKB method. Finally, we study the deflection angle, i.e., gravitational lensing, in both the weak and strong deflection limits.

Enhanced corrosion protection of steel strip through advanced Zn–Mg alloy coatings manufactured by Continuous Physical Vapor Deposition: A review

The growing global consensus on the “carbon peak and neutrality” has focused on high-strength steel, highlighting its critical role in enhancing energy efficiency, reducing emissions in the steel industry, and reducing the weight of automobiles. Traditional Electro-Galvanizing (EG) and Hot-Dip Galvanizing (HDG) technologies face challenges in meeting the surface protection demands of these applications. This limitation is evident with the development of Zn–Mg coated strip steel, which offers high corrosion resistance. Continuous Physical Vapor Deposition (CPVD) effectively addresses these issues in a sealed vacuum environment, drawing significant attention in the strip coating industry owing to its superior surface quality, diverse material options, and environmental advantages. This article reviews the latest advancements and current status of Zn–Mg alloy coatings prepared using the CPVD technology. It discusses the typical thermal evaporation process used in CPVD, traces the development history of CPVD coatings on strip steel, and examines the microstructure, corrosion resistance, and adhesion performance evolution mechanisms of Zn–Mg alloy coatings. By designing multilayer structures, adjusting the Mg composition, and implementing controllable heat treatments, the overall performance of the coatings is enhanced. This study also comprehensively analyzes the feasibility of applying multilayer, highly corrosion-resistant Zn–Mg coatings. Additionally, it identifies the main challenges in applying CPVD technology to Zn–Mg coatings on strip steel, such as the large-scale, stable, and low-cost mass production of typical processes and controlling the void content at multilayer interfaces. Finally, future research directions are anticipated, underscoring the potentially significant impact of further alloying and computer simulations in advancing steel surface treatments.

Numerical analysis of evaporation process in the heating column of a solar water desalination plant under various geometries, ambient conditions, solar radiations, and time steps

Solar-powered desalination offers a promising and sustainable method for producing potable water. In this study, the heating column of a solar desalination powerplant is numerically investigated under different novel geometric/structure scenarios, various solar/ambient conditions and different seawater salinity through different time steps. The primary objective is to identify the optimal configuration that maximizes water evaporation within the heating cylinder which has not been carried out before. Initially, four distinct heating cylinder configurations are examined under a fixed time step. The most promising configuration is then selected and evaluated under a broader range of ambient conditions and the same time step. The influence of solar radiation throughout the day is also analyzed. Finally, the evaporation process is simulated for the selected geometrical and environmental conditions across different time steps ranging from 60 to 300 s. The findings reveal that incorporating fins alone, a glass cover alone, and a combination of both fins and a glass cover could enhance the volume fraction of vapor by approximately 8 %, 33.3 % and 10.6 %, respectively, compared to the baseline configuration without fins or a glass cover. However, the evaporation rate for the glass cover configuration increased with rising ambient air temperature. Additionally, the highest evaporation is observed at 15:00 p.m., corresponding to the peak solar radiation intensity. Under optimal conditions, the heating cylinder achieved a promising vapor volume fraction of approximately 78.2 % after 300 s. These findings offer valuable insights for optimizing solar desalination system design. By increasing the salinity of the water from 0 to 75 %, the value of steam volume fraction is reduced from 77 % to 60 % for a given time step.

Full-spectrum plasmonic semiconductor with stabilized oxygen vacancies enables VOCs purification for durable clean water capture

To mitigate health risks associated with volatile organic compounds (VOCs) in solar-driven water evaporation, we developed Au/WO2.72 material with full-spectrum absorption capabilities and dual photothermal and photocatalytic properties. Injecting hot electrons from Au nanoparticles (NPs) into WO2.72 preserves oxygen vacancies, thus maintaining the plasmonic effect and significantly reducing hot electron relaxation. This leads to enhanced purification of VOCs. The MF-Au/WO2.72 water evaporator, constructed on a melamine–formaldehyde (MF) substrate, demonstrated a water evaporation rate of 1.36 kg m-2 h−1 and stability over 6 h daily for 12 days under one sun irradiation. Importantly, it achieved a 92.9 % removal efficiency for phenol VOCs. Outdoor experiments validated its effectiveness in organic wastewater purification and seawater desalination, highlighting its potential for efficient and clean water production by simultaneously removing VOCs during the evaporation process. This work provides valuable insights into utilizing plasmonic-coupling materials for solar water purification.

Orientation optimization for high performance Mg3Sb2 thermoelectric films via thermal evaporation

Low-cost, highly efficient thermoelectric thin-film materials are becoming increasingly popular as miniaturization progresses. Mg3Sb2has great potential due to its low cost and high performance. However, the fabrication of Mg3Sb2thin films with high power factors (PFs) poses a certain challenge. In this work, we propose a general approach to prepare Mg3Sb2thin films with excellent thermoelectric properties. Using a two-step thermal evaporation and rapid annealing process, (001)-oriented Mg3Sb2thin films are fabricated onc-plane-oriented Al2O3substrates. The structure of the film orientation is optimized by controlling the film thickness, which modulates the thermoelectric performance. The PF of the Mg3Sb2at 500 nm (14μW·m-1·K-2) would increase to 169μW·m-1·K-2with Ag doping (Mg3Ag0.02Sb2) at room temperature. This work provides a new strategy for the development of high-performance thermoelectric thin films at room temperature.

Salt Resistant PPy/MXene Flexible Waffle Type Fabric for Efficient Solar Evaporation and Water Purification Production.

In recent years, with the development of solar seawater desalination technology, many solar evaporators are affected by precipitated salts during the evaporation process, which can reduce efficiency. In this work, flexible fabrics made of polypyrrole (PPy)/MXene are obtained by impregnating the prepared PPy ink onto waffle like fabrics. The combination of PPy and fabric greatly improves the water absorption and evaporation performance of the fabric. The average evaporation rate of this structure is 1.43kg m-2 h-1, and the average evaporation efficiency under a single light source is 85.13%. After a 15-h testing cycle and a total of 8 cycles, lasting nearly 120 h, the performance of the device remained stable. The structural characteristics of waffle fabric, based on the Marangoni thermal effect, make it possible to suppress salt precipitation during evaporation, avoiding large salt particles covering the evaporation surface and reducing efficiency. This experiment successfully demonstrated long-term stable water evaporation, providing new ideas for the development of fabric evaporators.

Dewdrop Metasurfaces and Dynamic Control Based on Condensation and Evaporation.

Dewdrops, the droplets of water naturally occurring on leaves and carapaces of insects, are a fascinating phenomenon in nature. Here, a man-made array of dewdrops with arbitrary shapes and arrangements, which can function as an electromagnetic metasurface, is demonstrated. The realization of the dewdrop array is enabled by a surface covered by a tailored pattern of hydrophilic and hydrophobic coatings, where tiny droplets of water can aggregate and form dewdrops on the former. Interestingly, this metasurface made of dewdrops can be modulated by the condensation and evaporation process. By increasing relative humidity and decreasing temperature, the dewdrop metasurface is gradually formed with increasing amounts of water. While the reverse operation can make it completely disappear. This idea is demonstrated through two examples with different functions of dynamically controllable microwave absorption and scattering. The work shows a principle to construct functional electromagnetic devices with dewdrops, as well as a mechanism of dynamic control based on condensation and evaporation, promising unprecedented applications.