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Surface tension plays a central role in the mechanical behavior of soft materials such as gels. Elastocapillary deformation of elastic graded substrates is ubiquitous in soft materials. In this work, the effect of a partially wetting sessile liquid droplet on the elastocapillary deformation of a soft elastic graded substrate is studied. The modulus is assumed to have an exponential form along the thickness direction. By applying the Fourier transformation, a mixed boundary-value problem is reduced into a dual integral equation. The numerical results show that the surface displacement is strongly affected by the inhomogeneity of the material. The study of the wetting properties of gel substrates is essential for both understanding the wetting phenomena of gels and developing gels for applications as soft actuators and sensors that can be used in wearable electronics and soft robotics. [ABSTRACT FROM AUTHOR]

In the present investigation, the effect of the disposition of the drip irrigation laterals on the potato yield was evaluated, using the partial drying of roots SPR, replacing a sheet of water of 100 and 50% of the evapotranspiration of the crop ETc. The experimental design was made based on the Completely Random Factorial Design considering two factors: (a) types of lateral arrangement (T-1 parallel arrangement and T-2 linear arrangement) and (b) irrigation types (100% ETc SPR1 and 50% ETc SPR2), obtaining four treatments as a result. The application of the SPR was carried out in two periods: the first, between days 20-29 after planting (during growth) and the second, between days 76-94 after planting (during maturity). Total and commercial yield as well as water productivity were evaluated. The results show that the type of irrigation had a greater incidence in the total yield of the crop with yields between 61 and 64 t/ha, while the disposition factor had a greater incidence in the commercial yield with yields between 51 and 60 t/ha. Water use efficiency varied between 38 and 47 kg/m3.

We carried out a comprehensive molecular simulation to investigate the evolution of the excess isotherms and the isosteric heat with respect to temperature for argon adsorption on strong and weak substrates. The temperature ranges from well below the bulk triple point temperature to above the bulk critical temperature to show the first- (second-) order transitions and the state of the system at the bulk coexistence pressure P0, whether it is non-wetting, partial wetting or complete wetting (preceded by pre-wetting). It is found that the key parameter that affects the dependence of the transitions on temperature and the state of the system at P0 is the relative difference between the isosteric heat and the heat of sublimation (or condensation). For strong substrates, the state of the system changes from partial wetting to complete wetting when the temperature crosses the bulk triple point temperature, and for temperatures well below the bulk triple point the 2D-condensation occurs in the first and second (and possible higher) layers. For weak substrates, the state of the system changes from non-wetting to complete wetting when the temperature crosses the wetting temperature TW, which is specific to the substrate. For temperatures greater than TW, complete wetting in weak substrates only occurs at pressures close to the bulk coexistence pressure P0 via the initial stage of clustering (unfavourable adsorption), followed by a pre-wetting (known as thin-to-thick transition), and this is reflected in the increase of the isosteric heat from a value less than the heat of condensation λ and approaching λ as the pressure tends to P0. [ABSTRACT FROM AUTHOR]

The article deals with the cavitation phenomenon affected by full and partial wetting of the wall. For the numerical computation of flow in the Laval nozzle the Schnerr-Sauer cavitation model was tested and was used for cavitation research of flow within the nozzle considering partial surface wetting. The coefficient of wetting for various materials was determined using experimental, theoretical and numerical methods of fluid flow due to partial surface wetting.

Graphical abstract Abstract Hypothesis Rotational Brownian diffusions of colloidal particles at a fluid interface play important roles in particle self-assembly and in surface microrheology. Recent experiments on translational Brownian motion of spherical particles at the air-water interface show a significant slowing down of the translational diffusion with respect to the hydrodynamic predictions (Boniello et al., 2015). For the rotational diffusions of partially wetted colloids, slowing down of the particle dynamics can be also expected. Experiments Here, the rotational dynamics of Janus colloids at the air-water interface have been experimentally investigated using optical microscopy. Bright field and fluorescent microscopies have been used to measure the in-plane and out-of-plane particle rotational diffusions exploiting the Janus geometry of the colloids we fabricated. Findings Our results show a severe slowing down of the rotational diffusion D r, ⊥ connected to the contact line motion and wetting-dewetting dynamics occurring on particle regions located at opposite liquid wedges. A slowing down of the particle rotational diffusion about an axis parallel to the interfacial normal D r, || was also observed. Contact line fluctuations due to partial wetting dynamics lead to a rotational line friction that we have modelled in order to describe our results. [ABSTRACT FROM AUTHOR]

Spontaneous capillary flow (SCF) in microchannels occurs for specific geometrical and wetting conditions. When the channel walls form corner angles with the channel bottom, liquid filaments may form in the corners. These capillary filaments are often called Concus-Finn (CF) filaments, and they can theoretically spread infinitely.In this work we consider rectangular open U-grooves of varying cross-section width, and we theoretically determine the flow conditions as a function of the aspect ratio of the channel and the liquid-solid contact angle. These flow conditions are numerically checked. Especially, we analyze the configurations where precursor capillary filaments form. We show that these filaments can be metastable, i.e. disappear into a bulk capillary flow if the proper conditions are met. A diagram of the flow regimes is deduced from theoretical developments and checked using numerical modeling.

• Derivation of two-dimensional Green's Function for Spherical Laplacian. • Use of multi-precision arithmetic for evaluation of Green's Function. • Evaluation of computation time for combination of pre-conditioners and Krylov methods. • PETSc based numerical calculations and comparison with Finite Difference Method (FDM). • Robustness of the Green's Function based approach over FDM is shown. The solution of the two-dimensional spherical diffusion equation inside the catalyst particle is proposed using Green's Function Method (GFM). A Green's Function was derived using Eigenfunction expansion in the polar direction and considering jump discontinuity in the radial direction. The advantage of using multi-precision arithmetic in the evaluation of Green's Function has been demonstrated. A pre-computed value of Green's Function at a selected precision level was used to calculate the concentration profile inside the fully and partially wetted spherical catalyst particle geometry. The non-linear kinetic rate expression-based formulation for concentration profile calculation gives rise to non-linear equations. These non-linear equations were solved in PETSc (Balay et al., 2017) using various combinations of linear pre-conditioners and Krylov methods. A comparison with the Finite Difference Method (FDM) formulation is presented, and the advantage of the proposed GFM-based formulation for convergence and reduction in computation time is demonstrated. [ABSTRACT FROM AUTHOR]

The spreading of small liquid drops over thin and thick porous layers (dry or saturated with the same liquid) is discussed in the case of both complete wetting (silicone oils of different viscosities over nitrocellulose membranes and blood over a filter paper) and partial wetting (aqueous SDS (Sodium dodecyl sulfate) solutions of different concentrations and blood over partially wetted substrates). Filter paper and nitrocellulose membranes of different porosity and different average pore size were used as a model of thin porous layers, sponges, glass and metal filters were used as a model of thick porous substrates. Spreading of both Newtonian and non-Newtonian liquid are considered below. In the case of complete wetting, two spreading regimes were found (i) the fast spreading regime, when imbibition is not important and (ii) the second slow regime when imbibition dominates. As a result of these two competing processes, the radius of the drop goes through a maximum value over time. A system of two differential equations was derived in the case of complete wetting for both Newtonian and non-Newtonian liquids to describe the evolution with time of radii of both the drop base and the wetted region inside the porous layer. The deduced system of differential equations does not include any fitting parameter. Experiments were carried out by the spreading of silicone oil drops over various dry microfiltration membranes (permeable in both normal and tangential directions) and blood over dry filter paper. The time evolution of the radii of both the drop base and the wetted region inside the porous layer were monitored. All experimental data fell on two universal curves if appropriate scales are used with a plot of the dimensionless radii of the drop base and of the wetted region inside the porous layer on dimensionless time. The predicted theoretical relationships are two universal curves accounting quite satisfactorily for the experimental data. According to the theory prediction, (i) the dynamic contact angle dependence on the same dimensionless time as before should be a universal function and (ii) the dynamic contact angle should change rapidly over an initial short stage of spreading and should remain a constant value over the duration of the rest of the spreading process. The constancy of the contact angle on this stage has nothing to do with hysteresis of the contact angle: there is no hysteresis in the system under investigation in the case of complete wetting. These conclusions again are in good agreement with experimental observations in the case of complete wetting for both Newtonian and non-Newtonian liquids. Addition of surfactant to aqueous solutions, as expected, improve spreading over porous substrates and, in some cases, results in switching from partial to complete wetting. It was shown that for the spreading of surfactant solutions on thick porous substrates there is a minimum contact angle after which the droplet rapidly absorbs into the substrate. Unfortunately, a theory of spreading/imbibition over thick porous substrates is still to be developed. However, it was shown that the dimensionless time dependences of both contact angle and spreading radius of the droplet on thick porous material fall on to a universal curve in the case of complete wetting.

This work presents a two-dimensional analytical solution of the governing differential equation for falling film vapour-absorption around a plain horizontal tube. The solution of the species transport equation gives the LiBr mass fraction distribution within the liquid absorptive film flowing along the tube surface and can be used to characterize the mass transfer performance of falling film absorbers or generators. By means of the inclusion of partial wetting effects at reduced solution mass flowrates, this study obtains an analytical expression of the mass transfer coefficient of these devices applicable over an extended range of operative conditions. The hypotheses of small penetration for physical absorption and constant heat flux condition are applied at the film interface to reach a closed-form solution. Fourier method is used to solve the problem and the eigenvalues obtained from the characteristic equation depend on Lewis number, Biot number and the dimensionless heat of absorption. Given the boundary condition at the wall, the two-dimensional mass fraction field of the laminar film can be expressed analytically as a function of Schmidt, Reynolds numbers, the tube dimensionless diameter and the ratio of the wetted area to the total exchange surface. Finally, mass transfer coefficient and absorbed mass flux are locally and globally investigated as functions of the influent dimensionless groups to clarify their effects on the physical process and screen the potentiality of the model. Results show notable qualitative and quantitative agreement with previous numerical solutions and experimental results from previous literature. This model constitutes a widely applicable and time-saving tool for actual system simulations, design and control. [ABSTRACT FROM AUTHOR]

To understand the thin film evaporation in a partial wetting system, water morphology near the receding contact line driven by evaporation has been investigated experimentally. A state-of-the-art tapping-mode atomic force microscopy (TM-AFM) was used to obtain the nanoscale film profile. The test section first reached equilibrium in an enclosed chamber. Then a small amount of heat was supplied to increase the gas temperature to achieve an environmental heating. The droplet was evaporating and the receding velocity of the contact line was below 20 nm/s. The film profiles were found following the macroscopic profile, which was about linear, till about 2 nm thickness from the contact line which was already the limitation of the measurement. The results indicate that the microscopic contact angle at nanoscale was approximately equal to the optically detected macroscopic contact angle under this weak environmental heating. [ABSTRACT FROM AUTHOR]

Single-phase as well as two-phase fluid flows inside mini/micro-channels and capillary tubes are of practical importance in many miniaturized engineering systems. While several issues related to single-phase transport are fairly well understood, two-phase systems still pose challenges for engineering design. The presence of gas-liquid interfaces, dominance of surface forces, moving contact lines, wettability, dynamic contact angle hysteresis and flow in confined geometries are some of the unique features of two-phase systems, which manifest into complex transport phenomena. While Taylor plug/bubble flow is a fairly common flow pattern in several micro-fluidic devices operating at low Bond number, the ensuing transport characteristics are complex and still not fully discerned. This review paper aims at highlighting the nuances and features of a unit cell of a Taylor plug flow, especially focusing on partially wetting systems, which are more common in engineering applications. Emphasis is given to a 'unit cell' flow system consisting of an isolated liquid Taylor plug with adjacent gas phase, confined in a capillary tube. Such a seemingly simple flow condition poses considerable challenges for discerning and modelling local thermo-hydrodynamic transport coefficients. Relevant background information and fundamentals are carefully scrutinized while summarizing the state-of-the-art. The role of wettability and dissipation near the contact line is highlighted via available experimental and simulation results. Local momentum and heat transfer exchange processes during the motion of an isolated plug of partially wetting liquid moving inside a capillary tube are delineated. [ABSTRACT FROM AUTHOR]

We report new analytical solutions for the thickness profile of partially wetting two-dimensional droplets. The model includes the effects of capillarity and both short- and long-range molecular forces. We analyze the dependence of the maximum thickness, the contact angle, and the cross-sectional area on the height of the nanometric precursor film that surrounds the droplet. We found asymptotic expressions for the thickness profile and for the contact angles for large and small droplets. The results are compared to those obtained previously for polar liquids. The analytical solutions found here are useful to assess the validity of the hypothesis and the semi-analytical solutions proposed in the literature. In addition, these solutions enable the inference of information about the molecular potential from the measured steady profiles. [ABSTRACT FROM AUTHOR]

The properties of the interface of two immiscible fluids play an important role in several processes such as membrane supported liquid extraction, enhance oil recovery, aquifer remediation, etc. In this paper the spatial distribution of two immiscible liquids in non-dispersive contact via a porous media is studied by using numerical simulations. The simulations are carried at pore-scale by minimizing the total interfacial energy using the simulated annealing method. This technique allows us to compute the spatial distribution of fluids in the pores without assuming the geometry of the solid or the interface. The studied solids are made of randomly packed spheres either monodispersed or bi-dispersed. The effect of pore size distribution, tortuosity, porosity and contact angle on the liquid–liquid interface extent and geometry is analyzed. The simulations demonstrate that liquid–liquid interface follows a simple linear correlation with the contact angle. At low contact angle the wetting phase extents into the non-wetting phase forming pendular liquid bridges. The continuity of the phases is evaluated. The liquid–liquid interface is mostly continuous for all the contact angles. [ABSTRACT FROM AUTHOR]

Evaporative triple contact lines are far from well understood, which is especially true for partial wetting. In the present work we obtain the water film profile down to about 1 nm from the contact line, through a state-of-the-art tapping-mode atomic force microscopy (TM-AFM). The test section is enclosed and the measurements are conducted under equilibrium state. The results show that the liquid surface is straight downward to the substrate. The microscopic contact angle is therefore identical to the macroscopic counterpart, which greatly facilitates the thin film modeling. The linearity of the equilibrium thin films is important for the comprehensive understanding of contact line region. [ABSTRACT FROM AUTHOR]

The paper reports an experimental study to understand the evaporation mechanism of a partially wetting isolated liquid plug (methanol) of length L moving inside a long, dry, horizontal circular glass capillary tube (ID = 1.5 mm). The plug (with specified range of non-dimensional L / D ratios) is pushed from rest by controlled injection of air from one side, till a quasi-steady terminal plug velocity is achieved in the adiabatic section (non-heated length) of the capillary tube. Under such conditions, the drainage of thin-film occurring at the receding interface and its subsequent dewetting is well predicted by existing literature. The plug is then allowed to move through the heated section maintained at constant wall temperature (lesser than the saturation temperature of methanol). The drained film now starts evaporating rapidly, drastically affecting the bulk transport behavior. High resolution videography, coupled with laser confocal microscopy provides vital bulk as well as local information, including time-varying plug length, film thickness and local dewetting behavior near the contact line. Experimental results obtained for different wall temperatures and different initial L / D ratios of liquid plug suggests that the Taylor’s law for predicting drainage characteristics under adiabatic flow conditions is valid, even for cases where there is a continuous evaporation of thin-film. The study thus provides a framework for modeling evaporative flux based on simple hydrodynamic theory of film drainage. [ABSTRACT FROM AUTHOR]

Falling film drain water heat recovery (DWHR) systems are single pass, vented heat exchangers. The heat from the drain water is transferred through the DWHR system to the incoming cold mains water, recovering otherwise wasted energy. This article discusses the theory behind DWHR systems, and examines how drain-side wetting affects performance. It also describes the apparatus built by the Solar Thermal Research Laboratory (STRL), at the University of Waterloo, for testing the effectiveness of DWHR systems. The results show that as the flow rate increases, the effectiveness of the DWHR pipe decreases. The data also indicates that there is a Critical Flow Rate (CFR) below which the performance of a DWHR pipe cannot be extrapolated. The inability to extrapolate is due to the incoming drain water not repeatedly wetting the same amount of area on the pipe's interior wall. This CFR is dependent on the diameter and interior surface characteristics of the pipe. [ABSTRACT FROM AUTHOR]

Abstract: Membrane gas absorption technology is a promising alternative to conventional technologies for the mitigation of acid gases. In this study, simultaneous removal of SO2 and CO2 from coal-fired flue gas was carried out in a polypropylene hollow fiber membrane contactor using aqueous monoethanolamine as the absorbent. The influences of liquid and gas flow rates on the simultaneous absorption performance of CO2 and SO2 were investigated. The experimental results indicated that the membrane contactor could eliminate these two sour gases simultaneously and effectively. Absorption of SO2 and CO2 was enhanced by the increase in liquid flow rate and decrease in gas flow rate. It was observed that a small amount of SO2 in the flue gas had a slight influence on the absorption of CO2. In addition, the membrane contactor was operated continuously for two weeks to evaluate its duration performance. The results showed that the CO2 mass transfer rate was decreased significantly with the operating time due to partial wetting of membrane pores. After 14days of continuous operation, the CO2 mass transfer rate of the wetted membrane contactor was decreased by 41% but could be retrieved to 86% of the fresh one by increasing the gas phase pressure. [Copyright &y& Elsevier]

Abstract: The membrane wetting by amine absorbents results in performance deterioration of membrane gas absorption system for CO2 post-combustion capture. To solve this problem, in this study, the polypropylene membrane fiber was modified by depositing a rough layer on the surface to improve its hydrophobicity. Weighing the coating homogeneity, hydrophobicity and modification process efficiency, the mixture of cyclohexanone and MEK system was considered as the best non-solvent. The contact angle increased dramatically from 122° to 158° by the modification, thereby obtaining superhydrophobic membrane surface. The membrane–absorbent interaction results demonstrated that the modification treatment effectively enhanced the stability and maintained the superhydrophobicity of fibers contacting with the absorbent. In addition, continuous CO2 absorption experiments for up to 20days were carried out in untreated and modified polypropylene hollow fiber membrane contactors, using 1molL−1 MEA solution as the absorbent. The long-term system operation results indicated that, even though additional mass transfer resistance was introduced by the surface coating, the modified polypropylene hollow fiber membrane contactor was still technically feasible for CO2 capture from the power stations. [Copyright &y& Elsevier]

Abstract: Hydrodynamics and transport phenomena inside Trickle Bed Reactors are strongly modified when superficial liquid velocity is not sufficient to insure a perfect wetting of catalyst particles. For this reason, the impact of partial wetting on catalyst effectiveness has been widely studied in past, in case of isothermal reactions. Heat transfer limitations, inside or outside catalyst particles, have also been investigated, but only in case of total wetting. In the present study, the effect of partial wetting is quantified numerically for various kinetics, mass and heat transfer limitations. When possible, an analogy is proposed between 1D and 2D models of particles. Robust rules are proposed to take into account for partial wetting in 1D-radial models of particles. The case of partial evaporation inside catalyst pores is also studied. Evaporation phenomena is approximated following a simple approach. Performed calculations show that the effect of partial wetting can affect very strongly catalyst effectiveness factors, especially in case of evaporation in the pores. The use of 1D approximations gives a good prediction of the global catalyst efficiency, as far as boundary conditions are symmetric between heat and mass transfer. Otherwise, 1D models are not relevant anymore. [Copyright &y& Elsevier]

Abstract: A mathematical model was developed to simulate the concentration profile in a gas absorption membrane (GAM) system. Carbon dioxide (CO2) absorption into an aqueous solution of monoethanolamine (MEA) was investigated in the GAM system. Three GAM modules were potted with polytetrafluoroethylene (PTFE) membranes and connected in series to measure CO2 concentration and CO2 loading profiles along the length of the GAM system. The model predictions for CO2 concentration and CO2 loading profiles along the length of GAM column were in excellent agreement with the experimental results. The average absolute deviation between the model and experimental results was 1.49%. The Wilson plot method was used to determine the membrane resistance, which was compared with a theoretical membrane resistance. It was found that the membrane mass transfer resistance calculated using the Wilson plot method could predict the CO2 concentration profile with a higher accuracy than the theoretical method. Partial membrane wetting was modeled to investigate the effect of membrane mass transfer resistance on the absorption performance and the overall mass transfer coefficient. The results showed that an acceptable membrane wetting for CO2 absorption in MEA solutions in GAM systems was 40%. A higher lean solution temperature increased the membrane wetting in the GAM system. The membrane mass transfer resistance in completely liquid-filled membrane pores accounted for 92% of overall mass transfer resistance. [Copyright &y& Elsevier]

Abstract: Selective absorption into a liquid is a widespread method to separate and concentrate sulfur dioxide from gas emissions, reducing air pollution and environmental risks. Process intensification can be performed first by the substitution of the equipment (e.g. scrubbers) for a membrane device to avoid drops dragging, and second by the substitution of the absorption solvent (e.g. N,N-dimethylaniline) for ionic liquids to avoid solvent volatilization. According to this intensification, a zero solvent emission process has been developed. The ionic liquid 1-ethyl-3-methylimidazolium ethylsulfate is used as the absorption solvent and the results are compared to the N,N-dimethylaniline results. A ceramic hollow fibre module is the membrane device where the sulfur dioxide absorption takes place. A gas stream with a typical composition of roasting effluents flows through the shell side and the absorption liquid flows counter currently by the inside of the hollow fibres. The influence of carbon dioxide in the absorption is also evaluated and the overall mass transfer coefficients are calculated. The difference between the estimated mass transfer coefficients and the experimental results for both solvents is discussed assuming partial wetting of the membrane. [Copyright &y& Elsevier]

The capillary imbibition of aqueous surfactant solutions into dry porous substrates is investigated from both theoretical and experimental points of view in the case of partial wetting. Cylindrical capillaries are used as a model of porous media to study the problem. It is shown that if the mean pore size is below a critical value, then the permeability of the porous medium is not influenced by the presence of surfactants whatever the value of the concentration: the imbibition front moves exactly in the same way as in the case of the imbibition of pure water. The critical radius is determined by the adsorption of the surfactant molecules onto the inner surface of the pores. If the mean pore size is larger than the critical value, then the permeability increases with increasing surfactant concentration. These theoretical conclusions are in agreement with the experimental observations. [Copyright &y& Elsevier]

We report an experimental investigation on advancing contact lines of large drops spreading on chemically patterned surfaces. The model substrates were prepared using microphotolithography allowing precise control of the position and the size of the wettability patterns. Experiments were performed exploring different surface geometries: from ordered to disordered fields of defects and from low to high surface densities. The shape of the contact line between two isolated defects was investigated as a function of the distance. Portions of the contact line on the defects and on the matrix were studied during spreading experiments and were related to the apparent contact angles measured from the final thickness of the drops. A modified Cassie equation based on the line fraction of defects is proposed. [Copyright &y& Elsevier]

Physical mechanisms are discussed and crude mathematical models with lumped parameters are developed, which explain the authors recent experimental data , concerning temperature hysteresis and multiplicity phenomena for α-methylstyrene (AMS) liquid–vapor hydrogenation on a single catalyst pellet. The interplay between endothermic vaporization and exothermic vapor phase reaction is elucidated. The results of this study may help to develop more sophisticated models and theory of hot spots formation and runaway phenomena in trickle-bed reactors. [Copyright &y& Elsevier]

Interfacial crystallization appears as a crucial stage in the numeral natural phenomena and technological applications, such as industry of semi-conductors and manufacturing of nano-whiskers. Interfacial aspects of heterogeneous crystallization are surveyed. The review is focused on the interplay of thermodynamic and geometric aspects of the interfacial crystallization. Thermodynamic considerations leading to the Wulff construction are discussed. Equilibrium shape of the crystallized particle in the contact with a foreign substrate giving rise to the Winterbottom construction is treated. The concept of equivalent equilibrium contact angle θ eq is introduced. The equivalent contact angle θ eq applicable for isotropic crystals does not depend neither on the volume of the crystallized particles nor on the external fields. Bulk contributions to the free energy of the particle such as the bulk heat release in the case of reactive contact or latent heat of crystallization do not influence the equivalent contact angle θ eq. Application of the Winterbottom constructions for prediction of the shape of nanoparticles grown on solid substrates is treated. Thermodynamics of interfacial crystallization is discussed. The thermodynamic condition predicting when surface crystallization is thermodynamically favored over homogeneous (bulk) crystallization is supplied. This thermodynamic relation coincides with the condition prescribing the partial wetting of a solid by its melt. Interfacial crystallization in its relation to the "coffee-stain" effect, salt creeping and development of anti-icing surfaces is addressed. Interfacial aspects of epitaxial growth of crystals are considered. The current state-of-art in the field is reviewed. [Display omitted] • Interfacial aspects of heterogeneous crystallization are surveyed. • Thermodynamic considerations leading to the Wulff construction are discussed. • Winterbottom construction predicting the shape of particles grown on solid substrates is treated. • The concept of equivalent equilibrium contact angle is introduced. • Thermodynamics of interfacial crystallization is discussed. • Interfacial aspects of epitaxial growth of crystals are considered. [ABSTRACT FROM AUTHOR]

To reveal the impact of soil moisture distributions on nitrous oxide (N₂O) emissions from wet soils irrigated by sub-surface drip irrigation (SDI) with different surface soil wetting proportions, pot experiments were conducted, with surface irrigation (SI) as a control. Results indicated that irrigation triggered N₂O pulsing effect in all SDI treatments, yet N₂O values reduced with the decrease of surface soil wetting proportions of SDI irrigated soils, and the occurrence times were lagged. The peak N₂O fluxes and the corresponding soil water filled pore space (WFPS), as well as the coefficients of determination (R²) of the exponential function between N₂O fluxes and soil WFPS, decreased with the reduction of surface soil wetting proportions with SDI treatment, and from the central sub-region to the periphery sub-region. The pulse period contributed most to the reduction of N₂O emissions in SDI compared to SI treatments and should be a key period for N₂O emission mitigation. Over the whole experimental period, the area-weighted average cumulative N₂O fluxes from SDI treatments were 82.3⁻157.3 mg N₂O m -2 lower than those from SI treatment, with periphery sub-regions of R3 and R4 (radius of 19⁻27 cm and 28⁻36 cm from the emitter horizontally) contributing to more than 75.8% of the total N₂O emission mitigation. These results suggest that reducing surface soil wetting proportions or the increments of topsoil WFPS for SDI irrigated soils is a promising strategy for N₂O emission reduction.