Particle distribution in a pipeline has been clearly visualized by a combination of a capacitance-computed tomography and 3D wavelets multiresolution. As a result, the steady and unsteady particles are decomposed to extract the dominant frequency level. The CT obtains the capacitance between 12 electrodes distributed around the outside of the pipeline. The particle and air distributions can be separated because of individual permittivity by the reconstruction technique. The technique calculates the permittivity distribution on the cross section from the capacitance values by an iterative method of inverse problem.

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The motion of rising bubbles in a cylindrical container is reproduced in a three-dimensional computer graphics. The time history of 3-D position and shape of bubbles is determined from stereoscope video images of real bubbly flow by using a conventional PTV technique. The OpenGL is used to produce the animation. The surface model is applied to draw the bubbles. In order to describe the bubbles in a realistic manner, a semitransparent color is used to draw the surface of bubbles. The swap buffer method is used to realize the real-time animation. Sequential panoramic images of the bubbly flow are achieved by using the present technique. It is found that the playing speed of animation depends on the power of CPU.

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Although we can run large scale 3D simulations using high performance parallel computers, it could be difficult to save enormous simulation results in a storage as raw data for post visualization. Thus results are desired to be directly visualized and stored as small size images during simulations. We have developed an Integrated Volume Rendering System which consists of two subsystems. One is the interactive parameter setting system which makes users easy to determine complex rendering parameters. The other is the batch rendering system which is directly called from FORTRAN code to perform the volume rendering with the parameters set by the above system.

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Interactive simulation technique is incorporated in SPH method which is one of computer simulation methods in modeling and calculating fluid flow by using particles. It is required in the interactive simulation, a simulated object is operated in real-time by equipments of graphical output and controlling device. In the present study, a prototype of simulation program is implemented using “OpenGL” graphics library with perspective for versatile environment of execution. A model of tub charged with liquid (water) and rectangle solid body, which is composed of 301 SPH particles, is investigated in two dimension. It is found that the motion of fluid is induced by the artificial movement of the solid body and a complicated free-surface structure is developed. It is concluded that interactivity facilitate our recognition of phenomena being reproduced in SPH simulation though there remains improvement regarding interactive device and graphical computer resources.

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This paper presents much information about YAG (532) laser dyes dissolved into oil which can be utilized to measure oil film thickness and temperature. A spectroscopy analysis was conducted to obtain fluorescence and absorptivity spectra using spectrofluorometer and spectrophotometer, respectively. Spectroscopic dependency of each single-dye on temperature was evaluated to discover the best indicator of temperature. Some promising combinations of two dyes were selected to be applied to Dual Emission LIF (DELIF) temperature measurement on the basis of this information. The possibility of DELIF were examined using a spectrofluorometer. Consequently, some of the best dye-combinations was recommended, which could make the most of DELIF and Emission Reabsorption LIF (ERLIF) film thickness measurement. The ratio-metric LIF technique was found to be very helpful for minimizing of photo-degradation errors originating from the dye-bleaching and oil-oxidation caused by high temperature.

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Laser speckle photography is a well-established optical method for quantitative measurements in solid and fluid flow with wide dynamic range. In conventional technique of this method, an analogue processing based on auto-correlation evaluation has been applied to reconstruct deformation, velocity or density gradient by using optical Fourier transformation of a double-exposed laser speckle pattern recorded on a photographic film. This technique can be improved in the spatial resolution, in the dynamic range and in the efficiency of image processing by applying the digital cross-correlation evaluation between the reference and the object speckle patterns, which are separately recorded. It is called digital laser speckle photography. In practical procedure of this method, both of the reference and the object speckle pattern are recorded by using a digital still camera or CCD camera. The same algorithm with cross-correlation evaluation in PIV is applied to reconstruct the distribution of the displacement of local speckle patter from the digital images of speckle patterns. This method is applied to density field measurements of finite amplitude standing wave induced in a horizontal duct in order to verify the practicability of this method.

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The ocean wave information is indispensable to grasp the ocean environment and also important to navigate ships economically and safety. Therefore, many research works about the way of measuring it have been done.
Remote sensing technology using a satellite image is the useful way to measure it. This technology isn't suitable for getting the more detailed information of the limited part, though it is suitable for getting the average information of the large area.
The projected light distribution method was kept proceeding to measure the detailed wave height distribution of the limited part. But, it's very difficult to exceed a laboratory scale
This paper presents the way to measure the unsteady wave height distributions using the wave surface inclination distributions. The wave surface inclination distributions are analyzed images of the reflected light from the surface light source with the color distribution, by applying the Photometric stereo method. An unsteady wave height distribution is measured by this method and compared with the results measured by super-sonic wave height meters. The results show good agreement with them.

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Two realistic methods are proposed for an accurate determination of motion fields under spatio-temporal non-uniform illumination. The reliability of determined motion velocity depends on conditions of image pattern and varying light illumination. The two methods combine a local and a global approach of optimization under the consideration of local reliability indices. These methods stabilize motion velocity at low reliability areas of images. The effectiveness of methods is shown by numerical experiments.

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A lot of PIV (Particle Image Velocimetry) techniques are proposed to obtain three-dimensional vectors in three-dimensional regions.
Generally, in the single aspect PIV method, it is difficult to measure the particle position of the sightline direction in high accuracy. Then, the ideas of the spatial filter were combined with the laser sheet and acquire flow velocity in the sightline direction in handily and high accuracy. The sampling speed of images is related to the accuracy of measurement in this method.
In this paper, a new technique is proposed to measure the three-dimensional flow velocities using multi-laser sheets. Particles are tracked as the quasi-particles in the three- dimensional positions. As the each three laser-sheets are prepared to assign positional information of sightline direction, three-dimensional vectors are obtained on multiple sections.
Uniform Flow fields are measured to calibrate this method and 3% precision limit is obtained. The nominal-wake of the model-scale ship is measured and compared the velocity distribution with previous 5-hole pitot probe data. Good agreement is obtained between them.

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In this study, the measurement accuracy of the image pattern correlation method PIV was investigated by using the simulation particles images created based on the given velocity profile. As the results, it was revealed that the performance of the velocity measurements depended on the template size, the velocity gradient and the particles condition such as the number of particles and the particles diameter.

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The genetic algorithm (GA) has been already effectively applied by the present authors to the particle pairing problem of the PTV (Particle Tracking Velocimetry) system software. However, from the viewpoint of practicability, the formerly reported algorithm still leaves some room for improvement, in particular with respect to the allowed number of particles to be tracked, the treatment of the unpaired particles between the frames and, finally, the computing time. This time, a number of new ideas have been introduced in the genetic encoding of the particle pairing problem as well as in the relating genetic operations, both with a view to reducing the computing time up to convergence and dealing with the unpaired particles more appropriately. At the same time, the formerly proposed ideas have been used in a more refined form in order to improve the performance of particle pairing.

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Gravity current is a very important phenomenon for the marine environment.
In order to understand overall structure of them, it is necessary to perform simultaneous measurement of front part and outer part around the nose. The aims of this paper were performing highly precise measurement of giving density information with color information.
As the experimental technique, neutral buoyancy particles of two colors were prepared for the fluid of each density and dispersed into each density fluid. Particle images are visualized by a laser sheet light source, and particles image are acquired with a high-speed video camera. The values in RGB color space are obtained from the picture and they are changed into the values in HSV color space. The images are separated to two colors is created by hue value threshold.
Velocity distributions are obtained from those pictures, using PIV technique of Hiraku et al.
As a result, it is shown that simultaneous velocity measurements of the front part and outer part using the each particle in each density are succeeded. Overall 2-dimensional velocity distribution has been understood.

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One camera and multi-layer laser sheet PIV technique has been studied in our lab. But its method couldn't measure the 3-dimensional reverse flow against the camera.
In this paper, a new technique is proposed to measure the 3-dimensional flow which contain the reverse flow by moving multi-laser sheet method.
Uniform tow fields are measured to calibrate this method. The wake flow of the model-scale ship is measured. It is compared the velocity distribution with previous 5-hole pitot probe data and previous method in our lab. Better agreement is obtained than previous method. Cavity Flow field is also measured to confirm and compared with LDV measurement in 3-dimensional flow. Good agreement is obtained between them.

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An improved Particle Tacking velocimetry (PTV) algorithm was proposed in the present paper. The path tracking of the traced particle was achieved through a recursive cross-correlation operation of small interrogation window around the studied particles at two time steps. The particles are tracked by using grid points velocities calculated by the recursive cross-correlation method. To reduce the tracking error, a variable interrogation window size setting which changed with the interrogation window size according with spatial density of particles was introduced to the recursive cross-correlation method. The performance of the improved algorithm is evaluated by the synthetic particle images.

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Velocity vectors obtained by PTV are distributed discretely depending on the number density of tracer particles seeded in a flow. Especially, 3-D PTV obtains smaller number of data in 3-D space compared to 2-D PTV In order to extract physical properties such as streamlines, voracity contour and so on, velocity vectors have to be rearranged in grid space. This paper shows the applicability of post-processing methods based on ellipsoidal equations for PTV data in three-dimensional unsteady flows. Performance of the algorithms was examined with Hill's spherical vortex and PIV standard images by VSJ. As a result, it is recognized that these algorithms are sufficiently available for three-dimensional unsteady flows.

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A three-dimensional particle tracking velocimetry has been developed to measure the bubbly flow. The system realizes to obtain not only velocity vectors of the liquid but also velocity vectors and geometries of the bubbles. Fluorescent particles were used as tracers for the liquid phase. Two different light sources were used to illuminate the object. Black lights with adequate band-pass filters were used as the ultra violet light source to illuminate the particles. Incandescent lights with red colored cellophane sheets were used as backlight to take the shadow image of bubbles. A high-speed color video camera was used with six mirrors to take stereo images of the bubbly flow. A digital color image processing was applied to separate the bubbles and the tracing particles in the video images. A natural convection of the bubbly flow in a vertical pipe was measured to demonstrate the capability of the present system.

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A new method to generate water mists tracer for airflow PTV, which do not pollute water surfaces, is developed. The water mist tracers are applied for a PTV measurement of flow around a helicopter.

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Field measurements of surface flow on a river were carried out by using a helicopter on June 11^th, 2001. The images were taken by a standard camera and an infra-red camera.

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The heat curing oil film method using thermosetting property oil film is a new oil film method. The heat curing oil film method, in which not only the plane flow pattern in wall surface but also oil film thickness of the steady flow can be measured, was newly developed. The heat curing oil film method was used for visualization of the air flow in the clearance of an externally pressurized circular thrust gas bearing with a central supply hole and was found to provide much useful information about flow.

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The tracer method using the tracer mixed oil paint in the volatile solvent was applied for the visualization of externally pressurized circular thrust gas bearing. The volatile solvent component evaporated within the tracer adhered in the bearing surface, and only the solute component remained in the bearing surface. The thickness shape of the tracer remained in the bearing surface was measured by laser focus displacement gage, and the adhesion position of the tracer was required based on the result. As the result, it was shown to be useful for this method measuring the tracer adhesion position with a high accuracy.

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On shock wave position in the clearance of externally pressurized circular thrust gas bearing, though visualization example by the schlieren method has been observed, it does not seem to find the example of visualizing the density distribution by the Mach-Zehnder interferometer with shock wave. In this study, the density distribution of externally pressurized circular thrust gas bearing has been visualized by the Mach-Zehnder interferometer.

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Heat curing oil film method using thermosetting property oil film is a new oil film method visualizing the steady flow. It is considered that the hardening characteristics of oil paste have an influence on the thickness of oil deposit on the wall surface. In this paper, the hardening characteristics of thermosetting property oil paste are measured by the penetrometer, and the effect of the rotation angle of the agitation on hardening characteristics of oil paste was discussed.

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There are two different phenomena : (i) “repulsion” and (ii) “reconnection” for the collision of two vortex rings. We succeed to classify these phenomena by analyzing time dependence of relative coordinate of two vortex rings. It is found that the component of traveling direction of the relative coordinate has an important role to analyzing final states.

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For the flow between rotating shaft and padded cylinder like a partial arc journal bearing, the critical Taylor numbers based on the pad clearance and cavity clearance were evaluated with changing cavity arc extent. Three types of phenomena have been found. In the first type, the Taylor vortices based on the cavity clearance were held throughout both regions of cavity and pad clearances. In the second type, the vortices based on the cavity clearance changed into those based on the pad clearance when they passed through the pad clearance, and downstream they returned to their former state. In the third type, the vortices based on the pad clearance were held throughout both regions.
For the flow field perpendicular to the axis, the velocity vectors were measured by PIV to discuss the three-dimensional construction of the flow near the pad.

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The objective of this work is a study of the fluid mixing in the self-sustained flow through the two-dimensional baffled channel. The repeated baffles are set on upper and lower walls with the pitch ratio W/h in the channel. The flow cases for W/h=6.0 at Reynolds number Re=100300 are investigated by visualization method, and frequency and amplitude of the flow are measured.

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The visualization of pulsatile flow in a wavy-walled tube for low flow rates is conducted by the aluminum dust method. We pay attention to the effect of Strouhal number on flow behaviors. It is found that, generally, the flow tends to remain stable in the accelerating phase and unstable in the decelerating phase. There exists a peak mass transfer enhancement at an intermediate Strouhal number, where inertia effects dominate the flow, while at low and high Strouhal numbers, the mass transfer enhancement is reduced, and the flows remain relatively stable.

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A concurrent-flow thin-liquid layer is placed over the intersecting-flow in diamond-shaped column bundles to compose a hybrid assembly in the present work. Flow visualization study is performed to observe streamlines around diamond-shaped cylinders by means of fluorescent dye illuminated with a laser light sheet. A laser Doppler velocimetry(LDV) is employed to determine the variations of velocity distribution and Reynolds stress on the horizontal and vertical sections around the concurrent-flow thin-liquid layer over the intersecting-flow. The concurrent-flow interaction of the thin-liquid sheet and the intersecting-flow is disclosed in diamod-shaped column bundles.

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As a first step for studying the effect of porous metal plate-type-fin on the melting process of latent heat storage, fundamental experiments using paraffin wax with the melting point of some 40°C have been conducted. In this study, melting processes for three kinds of heat storage systems, namely the system without any fins, and the systems with horizontal fin arrays and a vertical fin, are investigated under the same heating conditions. From the experiments, the melting pattern and the transient temperature change for each system are clarified. Further, natural convection flow in the system during the melting process is visualized using the photochromic technique. The visualization of the temperature field near the vertical heat source wall is also performed using the shadowgraph technique. From those visualizations, the characteristics of the velocity and temperature fields near the heat source wall are clarified for each heat storage system.

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By means of flow visualization methods, the flow patterns induced by an oscillating circular cylinder are investigated. As the oscillating frequency increases, it change from two-dimensional flow pattern to three-dimensional flow pattern, and symmetry of the flow pattern is lost, and sheded vortex direction also differ from each other. The experiment was investigated within the ranges of Kc=3.14 and β =4080.

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The aim of this study is mix and diffusive the flow using secondary flow that occured around the oscillations body in a fluid at rest. The detailed mechanism of flow by square cylinder performing oscillation has not been made clear. This report shows the flow patterns around single square cylinder by visualization method. The flow cases for amplitude of oscillation Kc=0.43.14 and frequency β=40140 are investigated.

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The variation of stagnation points and the behavior of vortices in the rear of semicircular cylinder in the uniform shear flow are studied by the visualization technique of the hydrogen bubble method. Especially, in the case of the shear flow, there was not a vortex on the side with the faster speed of the mainstream and it found that the vortex was generating only on the slower speed side.

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A study on flow around the micro device is strongly required in MEMS development. The objective of this paper is to study dependence of Reynolds number on reattachment process over a backward-facing step in low Reynolds number flow. The Reynolds number based on step height H is 190930 and vortex structure was observed by Digital Video Camera (DV Camera) in a Micro Sensing Wind Tunnel which was constructed in the present research program. The transition vortex structure is observed depending on Reynolds number.

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Flow visualization and multi-point simultaneous hot-wire measurements were made to study organized structures vicinity of roughness elements for the boundary layer over a k-type rough wall. Vortex structure in a groove is seemingly unsteady three-dimensional over a k-type rough wall but seemingly steady two-dimensional over a d-type rough wall. Frequency, duration and spanwise spatial scale were investigated and compared for inflows and outflows observed in the flow visualization and for ejections and sweeps detected in the hot-wire measurement.

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This research has been performed to clarify the oscillation of a separating shear layer over a cavity formed peripherally on a cylinder in a uniform axial stream. Experiments have been carried out for the cavity of a width-to-depth ratio of 4 in a water channel. Measurements have been made along the shear layer using UVP monitor. The spatio-temporal behaviors of the separated shear layer are examined with POD and orthonormal wavelet transform. Maps of the mean velocity vector and vorticity are shown from the PIV measurement.

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This paper presents an active flow control based on Pyragas' Delayed Feedback Control theory. in this control system, fluid flow is observed by Particle Tracking Velocimetry (PTV), and using obtained flow field information two Synthetic Jet actuators control an unstable flow filed in a rectangular tank. The actuators can vector jet by synthesizing suction and blowing actions, therefore several patterns can be produced in a flow field.

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Mixing and diffusion characteristics of an axisymmetric water jet were investigated by a flow visualization technique. A laser florescent dye and a laser light sheet were used to visualize the water jet. The three-dimensional views of vortical structures were constructed by applying the Taylor hypothesis to the jet cross-sectional images. From the images, the boundary surface area, the unmixed area, the complexity and the fractal dimension were calculated to discuss mixing and diffusion. The result suggests that the simultaneous enhancement of axisymmetric and streamwise vortices is very effective to increase mixing.

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It was found that higher nozzle efficiency and loading ratio are obtained by mounting the injection port at the entrance of the suction nozzle. In order to improve the efficiency of the nozzle, the entrance shape of the suction nozzle is examined by changing the radius of the edge of the nozzle, as to reduce the large separation region created at the entrance of the nozzle. Furthermore, the sub-holes are mounted at the top of the injection nozzle and wider fluidization of the particles bed could be preformed. As a result, most provable nozzle shape is decided for the given conditions.

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The compound choking phenomena by confluence of two subsonic streams flowing in the same converging duct were experimentally investigated by the optical observations as well as the pressure measurements. A criterion for the compound choking is shown and discussed. Also, the experimental data are compared with the results calculated by using an inviscid one-dimensional model.

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When cooling tubes installed in plasma-facing components (PFCs) of a fusion reactor are damaged by some accidents, water may be discharged into a plasma chamber (PC) and vacuum vessel (VV) of the fusion reactor. In such a case, the discharged water will impinge on a surface of PFCs at high temperature and evaporate and then the VV may be broken due to pressurization by steam. This event is called an ingress-of-coolant event (ICE). The water-vapor two-phase flow behavior in the PC and VV during the ICE was investigated using an integrated ICE test facility. Furthermore, the condensation effect due to vapor inside a suppression tank which is installed to reduce the pressurization by the ICE was observed visually. In addition, the thermal-hydraulics during the ICE were validated numerically by the TRAC-PF1 code and analytical results on the pressure rise were in good agreement with the experimental results.

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A cold moderator using liquid hydrogen is one of the key components in a MW-scale spallation target system, which directly affects the neutronic performance both in intensity and resolution. Flow visualization experiments were carried out in order to clarified a flow field in a cold moderator vessel, the impinging jet induced flows such as recirculation flows and stagnant regions were verified in a moderator vessel. As for a cylindrical moderator vessel, analytical results, such as turbulent energy distribution and heat transfer coefficients, obtained with a non-linear turbulent model predicted experimental results obtained with a PIV system better than those with other turbulent models.

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The experiment for making of particle trajectory image analysis was almost carried out under glass beads particle (420 μ m diameter), layer high condition (layers high 50mm) in the two-dimensional fluidized bed of 80mm width, 150mm height, 3mm depth at pressure condition 0.1MPa. The consideration on the interaction of the bubble-inter-particle was tried, while features of the bubble behavior were understood, particle behavior of the bubble circumference though tracer particle painted black is entrapped in the particle bed, and though visualization image by transmitted light is acquired by the high-speed video, and though it refers to visual observation, PIV image analysis besides.

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The effects of cohesiveness and subsequent agglomeration of particles on the particle behavior and heat transfer characteristics around the horizontal tubes were experimentally studied. The inter-particle cohesive forces due to a liquid bridge were controlled by changing the humidity of the fluidizing air. The behavior of the particles and the bubbles on the tube surface were visualized by throwing a laser light sheet from the inside. This proposed visualization method can clearly distinguish the particles making contact with the tube surface from the bubble.

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A pressure sensitive paint (PSP) measurement is recently known as a pressure field measurement technique based on oxygen quenching phenomenon of luminescence of specific luminophores. A PSP measurement was applied to a pressure field measurement in a low-solidity circular cascade diffuser of a single-stage transonic centrifugal compressor at 17, 800 rpm with 5 in pressure ratio for HFC134a gas. The oxygen concentration was about 500 ppm based on the measured velocity of sound of the gas. Ru (bath-phen) was used as a PSP. The PSP was adsorbed on a silica-gel thin-layer chromatography sheet, and the sheet was fixed on the side-wall between the cascade vanes. The luminescent intensity drastically changed during a surge condition. And the pressure variations based on luminescent intensity agreed well with the pressure fluctuations measured using semiconductor pressure sensors with high-frequencyresponse at three points. It was shown that a PSP measurement worked well to investigate unsteady pressure fields in a transonic centrifugal compressor. However, there are still some problems to be overcome.

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The powerful jet noise containing discrete frequencies had been studied for the supersonic jet issuing from asymmetric nozzle with the oblique outlet. The discrete frequency noise was discussed to clarify the noise characteristics and generation mechanism. The behavior of supersonic jet was visualized by the instantaneous shadowgraph method. The vibration of total pressure in supersonic jet was measured using the probe having the built-in pressure transducer. The frequency spectrum of total pressure was analyzed using FFT. As the result, it was found that the peak frequency of total pressure vibration was mostly in agreement with the first peak of discrete frequency noise.

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Development of a high suction performance pump inducer is required for a high-performance rocket system to reduce total weight of a launch vehicle and to increase its reliability. It is very important for a high suction performance inducer design that the relation between flow patterns and cavitation structures makes clear. In this study, flow patterns observed with PIV system and cavitation structures observed with a high-speed camera are reported and discussed about their relationship.

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Since I started my career in an industry in 1949, I had been engaged in research and development concerning experimental techniques as an experimental engineer. In particular, I devised various flow visualization techniques that were eventually employed for development and innovation of such products as Machineries and plants. In 1985, I moved to the present University where I continued to improve flow visualization techniques using a smoke wind tunnel and produced significant results in transferring those techniques to educating. Looking back these fifty three years, I am going to introduce to you results, I obtained from the flow visualization as long as I am allowed.

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A transient process to develop Bénard-Marangoni convection in a cavity with a free surface under horizontal thermal gradient is observed by a thermal camera. Tracer particles and laser light illumination are introduced to visualize the flow structures at surface and in the cavity at any section concerned. In the experiment of water, we confirm sensitiveness of the flow structures to the degradation of surface by a contamination of impurity. Convection flow velocity is highly affected by the contamination. A local Marangoni number is introduced to explain the sensitiveness of the flow structures and development to turbulent 3D convection. Existence of a region having negative local Marangoni number may characterize the transition from 2D flow to developed 3D convection.

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Meaurement of interface positions between liquid-liquid phases and liquid-gas phases are one of important problems in order to control chemical processes. We have developed ultra-sonic sensing methods for such interfaces in very corrosive chemicals. Two cells made of glass are used to evaluate sonic velocity and to confirm time difference between sonic source and interfaces. Each sound velocity in each phase of stratified layers agrees to that of pure liquid. Because sounds reflected from interfaces make complicated signals, we used a video observation to record sound signal and phenomena in the test cell and succeeded to recognize each reflected sound from each interface.

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Marangoni convection, driven by an interfacial instability due to a surface tension gradient, has become a large problem in the crystal growth on the ground or in a micro gravity environment. To suppress and control the convection is important for the material processing. Especially in the crystal growth by LEC or EFZ technique, in which the melt is encapsulated with an immiscible medium, Marangoni convection may occur on the liquid-liquid interface and on the gas-liquid free surface. In the present paper, experiments were carried out with a two immiscible liquids layer both in a open-boat system and in an enclosed system. Flow in a cavity subject to a horizontal temperature gradient was observed. An interactive flow near the interface was measured by using a simple Ply technique. The measured flow field seemed to agree enough with the numerical prediction.

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Novel optical surface-visualization technique has been applied to aqueous solution systems of 1-pentanol and four structural isomers for investigating relations between molecular structures of alcohols and mechanical stabilities of their aqueous solution surfaces. Experiments have been carried out systematically under condition of various alcohol concentrations up to their solubilities with several sets of surface temperature gradients imposed just on the solution surfaces. Results of the analysis show that aqueous solution systems of alcohols which involve hydroxyl groups or methyl groups on appropriate positions in the molecules, such as 3-pentanol or 2-methyl-1-butanol, have relatively small instabilities of adsorption and large potentials for inducing strong surface disturbances at the solution surfaces.

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