Surface Tension Parameters Research Articles

Enhanced piroctone olamine retention from shampoo for superior anti-dandruff efficacy.

Dandruff is a pervasive chronic condition which negatively impacts quality of life. Effective treatment requires efficient delivery of scalp benefit agents that control commensal scalp Malassezia levels. Delivery of benefit agents from shampoos requires balancing many technical parameters to achieve the desired outcome without sacrificing secondary parameters, such as cosmetic attributes. To develop formulation technologies that increase the shampoo delivery efficiency of the scalp benefit agent piroctone olamine (PO). Increased delivery should result in increased anti-dandruff efficacy. Micellar Stability and Association parameters were quantified via dynamic surface tension and nuclear magnetic resonance (NMR) diffusion parameters, respectively. PO delivery has been assessed in vivo both on the scalp surface and follicular infindibula using extraction procedures and analytical analysis. Clinical anti-dandruff efficacy was assessed for an advanced delivery technology prototype in comparison to standard delivery technology. Shampoo prototypes have been developed that increase the delivery efficiency of PO. Both surfactant and polymer coacervate-based approaches have been developed. Decreased micellar stability results in weaker association between PO and micelles, resulting in more efficient PO retention on the scalp surface and delivery to the infundibula. Increased charge density of cationic polymers optimizes coacervation enabling improved PO delivery as well. Increased PO delivery has been shown clinically to result in higher anti-dandruff efficacy as measured by both visible flakes and underlying biomarkers. Increased efficiency PO delivery shampoos have been developed by optimization of both surfactant and coacervate parameters. The increased deposition efficiency results in significantly more products with significantly greater anti-dandruff efficacy.

COMPARATIVE ANALYSIS OF NEW MONOMER AND GEMINI SURFACTANTS SYNTHESIZED ON THE BASIS OF DODECANOIC ACID AND ETHANE-1,2- DIAMINE DEPENDING ON THEIR MOLAR RATIO

This article includes thorough information on the synthesis process and physicochemical properties of the products generated from the reaction of dodecanoic acid and ethane-1,2-diamine IR spectroscopy was used to confirm the structure and composition of the reaction products. Several parameters of the obtained surfactants were distinguished, including surface tension, electrical conductivity, and petro-dispersing parameters. Comparative analysis has been given based on the properties of the mono and gemini surfactant. At last, final suggestions were made, taking into account the salts' applicable qualities.

Thermodynamic modelling of physico-chemical properties of new generation ionic liquid-bitumen system

A-priori modelling framework of task-specific ionic liquid (TSIL)-bitumen system has been established. The TSIL is also referred as new generation IL. Various physico-chemical properties including density, surface tension, viscosity, and solubility parameter are predicted for various pure TSIL, bitumen, and TSIL-bitumen mixture. The bitumen samples taken under consideration are mainly from the Canadian region. Hence, this work provides a qualitative comparative analysis of bitumen extraction efficiency obtained from various TSIL over bitumen samples from oil sands of the Canadian region. The modified Lydersen-Joback-Reid method has been used to compute the critical properties of TSIL and bitumen fractions. Further equation of state models are used to predict the density and solubility of the same. Cubic equation of state (EoS) and geometric similitude concept have been applied to predict the surface tension and viscosity. Hence, the modelling framework elaborated in this study will serve as a connecting link between the existing data and the upcoming development.

Behavior of Auramine O in the Aqueous Solution of Two Kolliphors and Their Mixture

The studies on the behavior of Auramine O (AuO) at the water-air interface and in the bulk phase of the aqueous solution of Kolliphor® ELP (ELP) and Kolliphor® RH 40 (RH40) and their mixture were based on the results obtained from the measurements of the contact angle of water, formamide and diiodomethane on the polytetrafluoroethylene covered by the AuO layer, the surface tension of the aqueous solution of AuO, AuO + ELP, AuO + RH40, AuO + ELP + RH40, density and fluorescence intensity. Based on the obtained results, it was possible to determine components and parameters of the AuO surface tension, concentration and composition of the mixed monolayer, including AuO, ELP and RH40, as well as that of the mixed micelles, and to determine the Gibbs standard free energy of adsorption, micellization and AuO solubilization. The obtained results also showed that surface tension isotherms of the studied solutions can be described by the Szyszkowski equation and the exponential function of the second order and predicted by the Fainerman and Miller equation. In addition, the mixed surface layer composition can be predicted based on the contribution of the components of this layer to the water surface tension reduction.

Synthesis of Gemini cationic surfactants based on natural nicotinic acid and evaluation of their inhibition performance at C-steel/1 M HCl interface: Electrochemical and computational investigations

Herein, we prepare effective Gemini cationic surfactants (CSII, CSIV) and characterize them using FT-IR and 1HNMR spectroscopy. The adsorptive properties of CSII and CSIV at HCl/air and C-steel/HCl interfaces were examined with surface tension and electrochemical parameters, respectively. The critical micelle concentration (CMC) of the CSII and CSIV indicated their adsorption affinity at the HCl/air interface. Where, aliphatic chains increase surface coverage percentage and aid in surfactant adsorption. The electrochemical parameters of C-steel in 1 M HCl were studied using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) at different temperatures. The charge transfer resistance of the C-steel electrode was enhanced from 28.2 Ω.cm2 to 770.79 and 831.45 Ω.cm2 after adding 5 × 10−4 M of CSII and CSIV, respectively. Both CSII and CSIV act as mixed inhibitors with inhibition performance exceeding 97% due to their highly adsorption affinity. The chemical adsorption affinity of these compounds is suggested by the higher adsorption energy (∆G*ads) values (>−40 kJ mol−1) according to the Langmuir isotherm model. The theoretical calculations including DFT, and Monte Carlo simulation (MCs) provide insight into the relationship between corrosion inhibition and molecular structure, where the calculated parameters agree with the experimental results.

Novel and accurate mathematical simulation of various models for accurate prediction of surface tension parameters through ionic liquids

Ionic Liquids (ILs) as a novel class of liquid solvent simultaneously carry the positive characteristics of both molten salts and organic liquids. Remarkable positive properties of ILs have such as low vapor pressure and excellent permittivity have encouraged the motivation of researchers to use them in various applications over the last decade. Surface tension is an important physicochemical property of ILs, which its experimental-based measurement has been done by various researchers. Despite great precision, some major shortcomings such as high cost and health-related problems caused the researchers to develop mathematical models based on artificial intelligence (AI) approach to predict surface tension theoretically. In this research, the surface tension of two novel ILs (bis [(trifluoromethyl) sulfonyl] imide and 1,3-nonylimidazolium bis [(trifluoromethyl) sulfonyl] imide) were predicted using three predictive models. The available dataset contains 45 input features, which is relatively high in dimension. We decided to use AdaBoost with different base models, including Gaussian Process Regression (GPR), support vector regression (SVR), and decision tree (DT). Also, for feature selection and hyper-parameter tuning, a genetic algorithm (GA) search is used. The final R 2 -score for boosted DT, boosted GPR, and boosted SVR is 0.849, 0.981, and 0.944, respectively. Also, with the MAPE metric, boosted GPR has an error rate of 1.73E-02, boosted SVR has an error rate of 2.35E-02, and it is 3.36E-02 for boosted DT. So, the ADABOOST-GPR model was considered as the primary model for the research.

The effect of electrospinning parameters on morphology and diameter of polyethylene terephthalate (PET) and recycled polyethylene terephthalate (r-PET) nanofibers

Nanofibers are high surface-to-volume ratio structures that are widely used today. Due to rising demand, the obtaining of desired structures requires the use of various polymers in the electrospinning process as well as the control of their parameters. In this study, different concentrations of PET and r-PET polymers were prepared in a TFA:DCM solvent mixture. Viscosity, electrical conductivity, surface tension, and pH parameters of the solutions tested and their suitability for needle electrospinning are evaluated. Nanofibers with varied flow rates and needle-to-collector distances were produced using solutions. The statistical variation of the average fiber diameter (AFD) of the produced nanofibers was calculated. Statistical modeling and experimental data compatibility were determined to be high as 99.21%. As a result, the concentration observed increased the AFD for both polymer solutions. While the increase in flow rate led to an expansion of the AFD distribution, the change in needle tip–collector distance did not have a significant effect on the AFD.

Unit conversion in pseudopotential lattice Boltzmann method for liquid–vapor phase change simulations

Pseudopotential lattice Boltzmann (LB) model is an effective mesoscopic method for liquid–vapor phase change simulations. In LB methods, calculations are often carried out in lattice units. Thus, a correct mapping from the lattice unit system to the physical unit system is crucial for accurate simulations of practical problems. The unit conversion for liquid–vapor phase change problems is more complicated than single-phase problems, because an equation of state (EOS) for a nonideal fluid is introduced in the pseudopotential two-phase model. In this work, a novel unit conversion method for the pseudopotential LB model is proposed. The basic strategy is to obtain the conversion relations of fundamental units by mapping the surface tension and EOS parameters related to fluid properties, and thus, the unit conversion relations of other quantities are deduced. Numerical simulations of benchmark problems including the film evaporation and the bubble heterogeneous nucleation from a V-shaped cavity are carried out, and the simulation results are converted to the physical unit system by the proposed method. The numerical results demonstrate that the proposed method is able to recover the physical-unit latent heat of the fluid in the film evaporation problem. In the bubble nucleation from a V-shaped cavity problem, the conventional unit conversion method cannot derive the correct superheat temperature in the physical unit, whereas the proposed method based on the fundamental units recovers the critical superheat temperature which is consistent with the analytical result.

Surface tension effect on the sliding inception between an elastic sphere and a rigid flat

This paper develops an analytical model to characterize the sliding inception of elastic spherical contact accounting for surface tension effect. The distribution of von Mises equivalent stress on the contact interface under pure normal loading is first formulated, and thereby, the maximum allowable local shear stress is determined based on the concept of interface yielding failure. Then, the maximum tangential load that the contact interface can bear, and the friction coefficient at the sliding inception are obtained, which are functions of the normalized interference, the Poisson's ratio, and a surface tension-related parameter. The results show that the role of surface tension in the state of sliding inception primarily gives credit to its influence on the change of contact area. Based on this observation, explicit expressions of the maximum tangential load and the static friction coefficient are derived. It is found that both the maximum tangential load and the static friction coefficient decrease with the surface tension parameter increasing. For a given material, the smaller the sphere is, the lower the friction coefficient is predicted, which is in agreement with relevant experimental results.

Renewable non-edible oils derived long chain (C24.1) bio-based zwitterionic surfactant with ultralow interfacial tension between crude oil and formation brine

A new ultra-long chain monounsaturated 4-(N-nervonicamidopropyl-N,N-dimethylammonium) butane sulfonate (NDAS) zwitterionic surfactant with ultralow interfacial tensions was developed through the modification of nervonic acid derived from renewable non-edible seed oils by a simple and effective method. Its structure was characterized by ESI-HRMS, 1H NMR, and 13C NMR. NDAS surfactant exhibited a strong interfacial activity (∼10−4 mN/m) between the crude oil and the formation brine at a very low surfactant dosage (0.05 g/L) and at high salinity conditions, which is equivalent to 2% (w/w) of dosage of the most traditional surfactants used in the enhanced oil recovery field. Meanwhile, at a very low concentration (0.05 g/L), NDAS demonstrated strong NaCl compatibility up to 100 g/L, Ca2+ ions compatibility up to 200 mg/L, and temperature stability up to 90 °C. The surface tension, emulsification, and biodegradability parameters were also evaluated. This work consolidates our hypothesis that increasing the hydrophobic chain length of a surfactant certainly contributes to the high interfacial activity and good compatibility of salts and temperatures. Hence, it will facilitate the design of a sustainable alternative to petroleum-based chemicals to develop bio-based surfactants and extend the domain of bio-based surfactants to new applications such as in enhanced oil recovery (EOR).

Liquid-Phase Exfoliation of Bismuth Telluride Iodide (BiTeI): Structural and Optical Properties of Single-/Few-Layer Flakes.

Bismuth telluride halides (BiTeX) are Rashba-type crystals with several potential applications ranging from spintronics and nonlinear optics to energy. Their layered structures and low cleavage energies allow their production in a two-dimensional form, opening the path to miniaturized device concepts. The possibility to exfoliate bulk BiTeX crystals in the liquid represents a useful tool to formulate a large variety of functional inks for large-scale and cost-effective device manufacturing. Nevertheless, the exfoliation of BiTeI by means of mechanical and electrochemical exfoliation proved to be challenging. In this work, we report the first ultrasonication-assisted liquid-phase exfoliation (LPE) of BiTeI crystals. By screening solvents with different surface tension and Hildebrandt parameters, we maximize the exfoliation efficiency by minimizing the Gibbs free energy of the mixture solvent/BiTeI crystal. The most effective solvents for the BiTeI exfoliation have a surface tension close to 28 mN m–1 and a Hildebrandt parameter between 19 and 25 MPa0.5. The morphological, structural, and chemical properties of the LPE-produced single-/few-layer BiTeI flakes (average thickness of ∼3 nm) are evaluated through microscopic and optical characterizations, confirming their crystallinity. Second-harmonic generation measurements confirm the non-centrosymmetric structure of both bulk and exfoliated materials, revealing a large nonlinear optical response of BiTeI flakes due to the presence of strong quantum confinement effects and the absence of typical phase-matching requirements encountered in bulk nonlinear crystals. We estimated a second-order nonlinearity at 0.8 eV of |χ(2)| ∼ 1 nm V–1, which is 10 times larger than in bulk BiTeI crystals and is of the same order of magnitude as in other semiconducting monolayers (e.g., MoS2).

Mucoadhesive and Antimicrobial Allantoin/β Cyclodextrins-Loaded Carbopol Gels as Scaffolds for Regenerative Medicine.

Allantoin and its β-cyclodextrin and hydroxypropyl-β-cyclodextrin inclusion complexes 1:1 have been used to prepare carbopol-based mucoadhesive gels. The gelation process occurred by adjustment with glycerol 10% in the presence of triethanolamine. The structural features induced by the presence of allantoin and the corresponding β-cyclodextrins inclusion complexes have been first investigated by infrared spectroscopy highlighting strong interactions within the gels network and ideal crosslinks for the self-healing behavior. The hydrophilicity of the gels was investigated by the determination of the surface tension parameters and the free energy of hydration. The interfacial free energy values indicated prolonged biocompatibility with blood. The gels-water molecule interactions in terms of sorption, permeability, and diffusion coefficients were evaluated by dynamic vapor sorption analysis. The self-assembly process through intermolecular H-bonding, the high hydrophilicity, the mechanical performance, the hydrolytic stability in simulated biological media, the biocompatibility with normal human dermal fibroblast (NHDF) cells, the mucoadhesivity and antimicrobial activity on selected microorganism species (S. Aureus and C. albicans) of the allantoin-based gels recommend them as promising scaffold alternatives in regenerative medicine.

Liquid partial surface tensions obtained by an adapted Good-Girifalco approach from interfacial tensions and DiPEVa solubility parameters

This publication highlights the achievement of partial surface tension properties of liquids using an adapted Good-Girifalco approach from interfacial tensions and DiPEVa solubility parameters. The proposed method is simple to apply, and different databases of interfacial tension of water and one of squalene were compared. The water interfacial tension data was appropriate for estimating the dispersive component of the surface tension. In contrast, the squalene interfacial tension is more accurate for calculating the polar component of surface tension because of the miscibility behavior of the liquids. The approach strengthens the relationship between solubility parameters and the surface tension parameter. Due to the enormous importance of 3DSP, especially HSP, for the current technological field, the extension of its physicochemical background to the surface tension parameter is of paramount importance for the area of ​​Materials Science. Thus, the data presented here are especially relevant for applications dependent on surface and interfacial phenomena or dielectric constant related to 3DSP.

A Semi-Automatic Workflow to Extract Irregularly Aligned Plots and Sub-Plots: A Case Study on Lentil Breeding Populations

Plant breeding experiments typically contain a large number of plots, and obtaining phenotypic data is an integral part of most studies. Image-based plot-level measurements may not always produce adequate precision and will require sub-plot measurements. To perform image analysis on individual sub-plots, they must be segmented from plots, other sub-plots, and surrounding soil or vegetation. This study aims to introduce a semi-automatic workflow to segment irregularly aligned plots and sub-plots in breeding populations. Imagery from a replicated lentil diversity panel phenotyping experiment with 324 populations was used for this study. Image-based techniques using a convolution filter on an excess green index (ExG) were used to enhance and highlight plot rows and, thus, locate the plot center. Multi-threshold and watershed segmentation were then combined to separate plants, ground, and sub-plot within plots. Algorithms of local maxima and pixel resizing with surface tension parameters were used to detect the centers of sub-plots. A total of 3489 reference data points was collected on 30 random plots for accuracy assessment. It was found that all plots and sub-plots were successfully extracted with an overall plot extraction accuracy of 92%. Our methodology addressed some common issues related to plot segmentation, such as plot alignment and overlapping canopies in the field experiments. The ability to segment and extract phenometric information at the sub-plot level provides opportunities to improve the precision of image-based phenotypic measurements at field-scale.

Содержание кремния в крови и синовиальной жидкости больных ревматоидным артритом: клинико-патогенетическая значимость микроэлементоза

Актуальность. Распространенность ревматоидного артрита (РА) среди населения земного шара составляет около 1 %, а среди отдельных популяций людей достигает 5–7 %. К факторам риска развития и высоких темпов прогрессирования РА относятся большие концентрации во вдыхаемом воздухе кварца (диоксида кремния), токсическое воздействие которого рассматривается как один из мощных патогенетических факторов этого заболевания. Цель. Оценка клинико-патогенетической значимости кремниевого микроэлементоза при РА. Материалы и методы. Обследованы 83 больных РА (22 % мужчин и 78 % женщин в возрасте от 22 до 75 лет; в среднем 45 лет). Длительность заболевания от первых признаков его манифестации составила 9 лет. Системная форма болезни диагностирована в 19 % случаев, серопозитивный РА по ревматоидному фактору установлен в 68 % наблюдений, по антицитруллиновым антителам — в 80 %. Содержание кремния (Si) в сыворотке крови и синовиальной жидкости у 19 больных определяли с помощью атомно-абсорбционного спектрометра SolAAr-Mk2-MOZe с электрографитовым атомизатором (Великобритания). С использованием компьютерного тензиометра PAT2-Sinterface (Германия) исследовали параметры поверхностного натяжения сыворотки крови и синовиальной жидкости при времени «жизни поверхности» 0,01 с, стремящемся к бесконечности, подсчитывали их соотношение. Результаты. РА сопровождается отсутствием достоверных изменений уровня кремниемии. Микроэлементоз Si связан с клиническими, рентгенологическими и сонографическими признаками течения заболевания, степенью активности и тяжестью артрита, а кремниевый дисбаланс участвует в патогенетических построениях суставного синдрома, поражении скелетных мышц, периферической нервной системы, причем показатели Si в крови могут обладать прогностической значимостью.

Marangoni Convection of Dust Particles in the Boundary Layer of Maxwell Nanofluids with Varying Surface Tension and Viscosity

The flow of nanofluids is very important in industrial refrigeration systems. The operation of nuclear reactors and the cooling of the entire installation to improve safety and economics are entirely dependent on the application of nanofluids in water. Therefore, a model of Maxwell’s dusty nanofluid with temperature-dependent viscosity, surface suction and variable surface tension under the action of solar radiation is established. The basic equations of momentum and temperature of the dust and liquid phases are solved numerically using the MATLAB bvp4c scheme. In the current evaluation, taking into account variable surface tension and varying viscosity, the effect of dust particles is studied by immersing dust particles in a nanofluid. Qualitative and quantitative discussions are provided to focus on the effect of physical parameters on mass and heat transfer. The propagation results show that this mixing effect can significantly increase the thermal conductivity of nanofluids. With small changes in the surface tension parameters, a stronger drop in the temperature distribution is observed. The suction can significantly reduce the temperature distribution of the liquid and dust phases. The stretchability of the sheet is more conducive to temperature rise. The tables are used to explain how physical parameters affect the Nusselt number and mass transfer. The increased interaction of the liquid with nanoparticles or dust particles is intended to improve the Nusselt number. This model contains features that have not been previously studied, which stimulates demand for this model among all walks of life now and in the future.

Self-stratifying behavior of a novel light-curable coating with gradient hydrophobic properties: Computational and experimental study

In this study, we report a rational approach to design a novel VOC-free self-stratifying light-curable coating containing bio-renewable materials based on the methacrylated gelatin (GelMA) and acrylated epoxidized soybean oil diluted by the acrylated glycidyl neodecanoate (AESO-CE). The self-stratified structures of the AESO-CE/GelMA coatings attained through the visible light curing were recognized by SEM-EDX and water contact angle (WCA) analyses. Hildebrand (δHild) and Hansen solubility parameters (δHans) of AESO-CE and GelMA were calculated by molecular dynamics simulation and Hansen solubility spheres, respectively. It was revealed that the computational immiscibility results had an illustrative agreement with the experimental incompatibility observations in different AESO-CE/GelMA weight ratios over time. Furthermore, the findings demonstrated that surface tension and solubility parameters can be considered when dealing with self-stratification prediction in the gelatin-soybean oil-based coatings. The results indicated that the coatings with both hydrophobic-hydrophilic natures with WCA of 66–84° can be achieved by a fast curing reaction without the aid of solvent evaporation. Besides, it was concluded that the stratifying level and surface hydrophobicity properties have been significantly affected by the AESO-CE/GelMA weight ratio and the mixture viscosity. Accordingly, this investigation provides a helpful insight to develop a green coating exhibiting gradient hydrophobic behavior, as a promising candidate for advanced breathable food and bio-applications.

DiPEVa, an interactive method for adjusting the three-dimensional solubility parameters to surface tension

There has been increased interest recently in studies that use the surface tension parameter to predict the dispersion behavior of liquids at the level of nanotechnology. These same studies use the solubility parameter methodology to assess the compatibility of these liquid mixtures. Both parameters have been analyzed separately, despite being closely linked by well-known physicochemical relationships. The present study deepens the interrelationship between these two parameters, proposing innovative three-dimensional solubility parameters (3DSP) adjusted for surface tension. Through this, it is possible to obtain the 3DSP components that can be used to model applications that depend heavily on surface tension, such as emulsions, inorganic dispersion, solvent and cosolvent selection, encapsulation processes, among others.

Solution Processing of Topochemically Converted Layered WO3 for Multifunctional Applications

Solution processing of nanomaterials is a promising technique to utilize in various applications owing to its simplicity and scalability. However, the studies on liquid phase exfoliation (LPE) of tungsten oxide (WO3) are limited, unlike others due to lack of commercial availability of bulk WO3 with layered structures. Herein, we report a one-step topochemical synthesis approach to obtain bulk layered WO3 from commercially available layered tungsten disulfide (WS2) by optimizing various parameters like reaction time and temperature. Detailed microscopic and spectroscopic techniques have confirmed the conversion process. Further, LPE has been carried out on topochemically converted bulk layered WO3 in twenty-two different solvents, and among studied solvents isopropyl alcohol-water (1:1) co-solvent system appears to be the best. This indicates that the possible values of surface tension and Hansen solubility parameters for bulk WO3 could be close to that of co-solvent system. The obtained WO3 dispersions in a low boiling point solvent enable to fabricate thin films with varying thickness using spray deposition method. The obtained thin films are used as active materials in supercapacitors without any conductive additives/binders and exhibited an areal capacitance of 31.7 mF cm-2 at 5 mV s-1. The photoelectrochemical measurements reveal that these thin films can also be used as photoanodes for photoelectrochemical water oxidation.

Effects of viscosity and surface tension on soliton dynamics in the generalized KdV equation for shallow water waves

Various theories have been formulated for the study of weakly damped free-surface flows. These theories have been essentially focused on the forces relatively perpendicular to the fluid particle such as pressure forces, while neglecting forces relatively parallel to the fluid particle such as viscosity forces. In this work, with the help of linear approximation applying on the Navier-Stokes equations, we obtain a system of equations for potential flow which includes dissipative effect due to viscosity. The correction due to the viscosity is applied not only to the kinematics boundary condition on the surface, but also to the dynamics condition modeled by Bernoulli’s equation. We show that, in the context of wave motion in shallow water, an expansion of the Boussinesq system can be decomposed into a set of coupled equations. The first equation depends only on the surface elevation for the right-moving, while the other equation depends simultaneous on the surface elevation for the right- and left-moving waves. The wave equation corresponding to the pure right-moving has the form of a generalized inhomogeneous Korteweg de Vries (KdV) equation with higher-order nonlinear and dissipative terms. We then investigate the soliton solutions of this equation by using the Hirota’s bilinear method. The results show that, both group and phase velocities are a decreasing functions of the viscosity and surface tension parameters, δ and τ, respectively. The width of the soliton increases with the parameters δ and τ. The effects of viscosity on the soliton dynamics are more pronounced and are amplified by the surface tension effects.