In the sea, which is affected by strong winds that cover the water surface with wind wave breakers, a strong turbulent boundary layer is generated immediately below the sea surface. To clarify the turbulent structure of the sea-surface boundary layer, it is necessary to measure correctly water particle velocity fields in that layer. However, there are great difficulties in the measurement because the sea surface is covered by developed wind waves accompanied by air bubbles, air flow separation, and large water surface displacements. In this study, a high-resolution PIV system, which can analyze high-speed and intensively fluctuating water particle velocities that are affected by breaking waves, is developed to obtain correctly the data of the water particle velocity fields immediately below the water surface. Further, investigation and modeling of the turbulent structure of the sea-surface boundary layer are performed based on the velocity data obtained by a water tank experiment using the high-resolution PIV system.

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In late years, the setting number of the surveillance cameras increases by for the purpose of security. The problem is the difficulty for a person to see all the pictures of the surveillance cameras, and the automation of the monitor is demanded. In this study, we introduce a labor saving method into the acquisition of the extrinsic parameters of cameras. We then develop a cooperated multi-cameras system which is calibrated in this way and is aimed at construction of security environment for burglers and suspicious objects.

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This study investigated about the continuity of momentum flux through an air-water interface. We conducted to measure air-flow and water-flow very close to a water surface in a wind wave tank using PIV technique. To evaluate of the continuity of momentum flux calculating from the friction velocity was very difficult, because we could not detect exact a mean water level to fit a log-law profile for the experimental data. The viscous stress affected not only the viscous sub layer but also the turbulent boundary layer. The ratio of the viscous stress in water-flow is from several percent to about ten percent. We deduced that the continuity of momentum flux calculating from the total stress was strongly affected by three-dimensional turbulent water-flow.

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The two-phase flow measurements using imaging technique for two-dimensional bubble measurements, so called Bubble Tracking Velocimetry (BTV) and PIV were conducted to the surf zone breaking waves. The characteristics of air bubbles in the surf zone such as bubble distributions, bubble size spectra, and turbulent characteristics of fluid velocity were measured with highly temporal and spatial resolutions in the laboratory. The temporal transitions of bubble size spectra were measured and the relationship between the gas and liquid phases were analyzed for the surf zone breaking waves.

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The X-band marine radar is an advanced remote sensing system that can observe onshore and offshore physical phenomena by analyzing the continuous radar images. The sea wave spectra and the ocean surface current distributions are evaluated by conversion of the radar images to three-dimensional spectral space. The accuracy of the evaluated wave spectra are validate by comparing with the data observed with the wave gages, and the results lead the acceptable accuracy of the wave spectra evaluated with the radar images. The whitecaps coverage is measured with the radar images and calibrated with the video image data. The measurement of the whitecaps coverage is difficult with the ordinary measuring apparatus, but this radar system can be applied easily for its observation. The long-term shoreline depositions are also analyzed with the radar images. The radar detects the shoreline deposition distribution easily, more than ordinary observation system.

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The new type turbidimeter, CT scanning-type turbidimeter is proposed in this paper. It is an optical system that can measure instantaneous turbidity distributions in the target cross section. Its target measurement area is 480 mm x 480 mm. The hardware of this system has no moving part, and measure the instantaneous turbidity distributions every 0.1 s without disturbing flow field. To evaluate turbidity distributions from observed raw data, the extended Bayesian method are employed in this system. The method is non-linearized and accuracy of the evaluation is improved in this system. This system is applied to the measurement of the suspended sediment of sand in a surf zone in laboratory experiments, and suitable distributions and behavior of the sand are observed with the system.

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The purpose of this study is to evaluate phenomenons of the plant physiology and ecology using the satellite observation data in a cool-temperate deciduous broad-leaved forest in central Japan. We compared the satellite observation data (Normalized Difference Vegetation Index: NDVI) with the ground observation data (shoot phenology change, litter fall, and SPAD). The seasonal variability of satellite-based NDVI showed good correlations with those of LAI (Leaf Area Index) and photosynthetic capacity.

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A new-type protective wall using Geo-synthetics has been proposed for a countermeasure of falling rocks. In order to investigate an appropriate loading capacity against for falling rocks, real scale protective wall was constructed and impact tests of falling rock were conducted. The imitated rock was impacted into the reinforced protective wall vertically by free falling. Acceleration of the falling rock at the moment of impact was measured by a three-directional accelerometer installed inside of the rock. The deformation of the wall was measured after impact of the rock. The overall deformation was investigated, however, inside condition of the wall was not understood. For understanding the inside condition in the protective wall, finite element analyses, which can be simulated the impact of materials, were conducted. In the numerical simulations, the real scale field tests were represented to predict the deformation and stress propagation in the wall by the impact of falling rock.

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This research analyzes the Taylor vortex flow between two concentric rotating cylinders with finite length. CFD result is compared with the experimental result measured by Particle Image Velocimetry method. The aspect ratio is small. The velocity profile in the axial direction is investigated quantitatively. The results of CFD and EFD show reasonable agreement.

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The forced wavelengths of Gortler vortices are easily given by the leading edge plates with varying the period of a saw-tooth edge, and the variation of the forced wavelengths makes transformation of secondary instability flows. The experiments with concave channel of 1 m radius of the curvature for main airflow velocity of 2.5m/s were performed using the leading edge plates. Variation in secondary instability flows was tested by smoke visualization and hot-wire measurement, and was examined from viewpoints of maximum disturbance amplitude Kmax. It was confirmed that meandering flows whose (Kmax)max varies linearly with the non-dimensional forced wavelength parameter Λ prevail at 100<Λ<200. On the other hand, horseshoe-type vortices with (Kmax)max= {-.7em}\ aisebox{1.1ex}{.} {.1em}\ aisebox{-0.2ex}{.} 0.35 are formed at Λ of 250 or greater.

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Stratified flow induced by an impulsively started rotating circular cylinder was observed by means of dye injection. Effects of Reynolds number and Froude number on the behavior of the vortical flow were examined. The evolutions of dyed vortex formation lead to subsequent layered formation of dyed flow pattern. During the vortex formation and the rearrangement of the vortices, flow patterns exhibit the behavior of oscillating motion. Both the Reynolds number and Froude number affected the radial length scale of the layered formation, while the wavelength was almost independent of Reynolds number.

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It is important to determine whether a particular cerebral aneurysm has a high risk of rupture or not so that it can be treated before subarachnoid hemorrhage occurs. Hemodynamic stresses, especially Wall Shear Stress (WSS), are considered to play an important role in formation, growth and rupture of the cerebral aneurysm. In this paper, we investigate WSS under the pulsatile inflow conditions in a realistic in vitro model of a cerebral aneurysm. The geometry of measurement model is constructed in a patient- specific manner using CT data. The stereo PIV measurement is conducted to obtain the velocity field in the cerebral aneurysm. We calculate the WSS distribution from PIV results and geometry data of lost model. The results show that overall WSS distribution in the model does not charge uniformly with time due to palsatile flow.

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Magnetotactic bacteria are a class of bacteria that has nano sized magnetic crystals inside their body and respond to geomagnetic field. This paper reports the experimental research on visualization of magnetotactic bacteria "Magnetospirillum Magnetotacticum" behaviors under no/DC/AC magnetic field. The motion of magnetotactic bacteria was observed using an optical dark-field microscope system. The images were taken using cameras, and measured by image processing techniques. Applying DC/AC magnetic field, it was observed that magnetotactic bacteria rotated in the direction of magnetic field.

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In order to investigate vascular diseases such as cause of atherosclerosis and myocardial infarction, it is important to investigate relationships between endothelial cells (ECs) covered with surface on blood vessels and blood flow stimulation using both of in vivo and in vitro experiments. In this paper, a blood vessel model for in vitro experiment was developed in order to evaluate the relationship between response of ECs and shear stress caused by blood flow. ECs were cultured in polydimethylsiloxane (PDMS) microchip, which made of (PDMS) microchip fabricated using usual soft-lithographic technique, by optimizing cells cultured condition such as surface coating on the wall. The microchip consists of a straight microchannel with 400 μm width, 100 μm depth and 2 cm long. It was confirmed to be confluent using a phase-contrast microscope. Velocity distributions to estimate shear stress on the ECs were measured using micro PIV system.

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HFOV (High Frequency Oscillatory Ventilation) is known as one of effective methods of the artificial ventilation. Pendelluft flow has been predicted as one of gas exchange mechanism by HFOV. However, detailed experimental analysis of the pendelluft flow has not been carried out because of experimental difficulties. The recent development of experimental technique overcame the difficulties, and the flow patterns of the pendelluft generated in bronchiole have been analyzed experimentally. In this report, time series measurement of the penndelluft flow generated in a micro-channel as a model of respiratory bronchiole by using micro-PIV technique.

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Experiments studying on the transition of the flow between concentric cylinders with the inner cylinder rotating and the outer one at rest have been made by means of flow visualization. In this study, an inner conical mirror has been used to observe the overall flow pattern at all times. Attention is focused on the effect of aspect ratio on flow regime and modulation. It has been found that the number of travelling azimuthal waves increases and modulation occurs at lower Reynolds number region with a decrease in the aspect ratio.

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In the present study, the two- and three-dimensional analyses for turbine blades subjected to flow-induced vibration are compared. To consider the time-dependent motions. of blades, an arbitrary Lagrangian-Eulerian formulation is employed. A complete Navier-Stokes solver incorporating a moving mesh and analytic solutions of the motion equations for the. blade translation and rotation are applied. In the flow-induced vibration condition, the drag, lift and moment coefficients exhibited the time history coupled with the same frequency as that of non-coupling fluid forces and the blade natural frequency. The magnitude of blade fluctuation gradually increased with the reduced velocity. Although the small-scale vortices showing the three-dimensional structure were generated, there were no remarkable differences between two- and three-dimensional simulation in the reduced velocity starting flow induced vibration and the amplitude of the blade displacement.

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Boundary effects with a short annulus of Taylor Vortex Flow (TVF) called Ekman boundary layer, are greatly related to the generation of the various modes in vortex structure. Parameters as the aspect ratio and the radius ratio (Γ and η) are important factors for flow bifurcation to these modes. In the present, the spatiotemporal velocity field in the TVF with a short annulus is visualized and measured by using the ultrasonic time domain correlation method (UTDC).

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This study simulates the collision between a vortex ring and an ensemble of small glass particles.The vortex ring, convecting with the self-induced velocity in a quiescent air, collides with the particles. The Reynolds number for the vortex ring is 2600, and the particle diameters are 50 and 200, um. The Stokes number St for the 50μm particle is 0.74, while the St value for the200μm particle is 11.4. The simulation reveals the particle motion depending on the Stokes number. It also highlights the effect of the Stokes number on the behavior of the vortex ring.

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In order to improve the heat transfer on the wall, impinging jets is used in various industrial applications and has been investigated experimentally and numerically so far. However, it is not enough to make clear the detail of vortical structure contributing to the heat transfer. In the present paper, DNS(direct numerical simulation) of the impinging jet is conducted in order to investigate the heat transfer through the control of vortical structure. The discretizations in space are performed with hybrid scheme in which Fourier spectral and 6th order compact scheme are adopted. As the control parameter, two cases of perturbations are imposed on the inflow boundary conditions. The detailed flow characteristics on wall are demonstrated, and the effect of control is discussed based on the statistical quantities and the visualized vortical structures.

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Very effective cooling methods have been required for high-temperature gas turbines. Reduction of cooling air also contributes to the improvement of jet engine performance, because the cooling air is bled from compressor of jet engine. Therefore, from this point of view, "Multiple inclined impingement cooling structure" for turbine shroud cooling has been invented by IHI, JAXA and authors' group. This cooling structure realizes 50% reduction of cooling air compared with conventional one maintaining same cooling efficiency. However detailed internal cooling behavior has not been clarified. This study is one of the researches in collaboration with IET, JAXA and us. The main purpose is to clarify the cooling behavior by Particle Image Velocimetry (PIV) and heat transfer measurement on the impingement wall by IR camera. In this paper, we describe the results of PIV for 4 types of acrylic test pieces (impingement angle=90°, 45°, 35°, 25°). The characteristics of time-averaged velocity, turbulence intensity and pressure drop were considered.

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This study is to clarify the flow structure of a three-dimensional wall jet discharged on a flat surface from a round nozzle. Instantaneous flow pattern parallel to the wall was visualized by depth-tuft method, and the feature of the large-scale structures existed in the present wall jet was examined. It was revealed that a streak flow pattern corresponding to a ridge pattern of tufts was dominant structure, and that the streaks were generated quasi-periodically. The flow following capability of the tufts was calibrated using a sinusoidally oscillating wind-tunnel.

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The vortex rings generated in non-circular jets are deformed and interacted three-dimensionally owing to self-induced velocity, and the vortex motion enhances mixing. To understand the mechanism of the mixing enhancement, it is crucial to make clear the three-dimensional vortical structure caused by the interaction of non-circular vortices. In the present study, the details of three-dimensional vortical structure of a rectangular jet of aspect ratio 4 is clarified using Large Eddy Simulation (LES), and the interaction mechanism of rectangular vortices is discussed, focusing the deformation of vortices. The simulation results reveal the details of the vortex interaction in the rectangular jet: the vortices deform owing to the non-uniform curvature effect, and the interaction of vortices generates hairpin vortices via vortex stretching.

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The purpose of this study is to manipulate the characteristics of the three dimensional jet issuing from rectangular nozzle (aspect ratio; AR=12.5) using a rectangular notch (notch aspect ratio; NAR=2.5, 7.5, 12.5 and 165). The flow visualization of the present three dimensional jets using a water channel, has been made to examine the effect of the difference of NAR on the development of vortex structure at Reynolds number Re(=Ue×d/v)=500 through-out this experiment. From the experiment, it was clarified that the streamwise variation of the vortex filament showed different development according to the magnitude of NAR.

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The effects of the contraction area ratio CR of orifice nozzle on the flow characteristics of the free jet issued from the nozzle are examined. The large vortex structure of submerged orifice water jet is visualized by tracer method and examined the effects of CR on it. The mean and fluctuating velocities of orifice air jet are measured by a single probe and hot-wire anemometry and the effects of CR on them are also examined. CR was changed from 1.00 to 0.11. As a result, (a) the centerline maximum velocity u _c/u _m (u _m: nozzle exit mean velocity) can be presented by u _c/ u _m=1.9 CR ³ -3.55CR ²+1.38 CR+1.53, and (b) the maximum of u _c/u _m=1.7 occurs at CR=0.27, and others were made clear.

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A development process of a low-density jet, such as a helium gas and a hot air jets, is different from that of a constant-density jet. Side jets, which are radial ejections, are formed at vicinity of the nozzle exit and mixing of fluids between the jet and the surroundings is enhanced. Helium gas jets were discharged from a round nozzle upward and visualized by planar laser Mie scattering (PLMS). A configuration of the side jets varies with Reynolds number. Side jets at low Reynolds number are similar to a bifurcation. A flow structure of the side jets at low Reynolds number was observed using a high-speed video camera. The side jets at the low Reynolds number is generated periodically.

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As a part of the study on the control of jet diffusion, the jet flow issuing from a circular pipe with fluttering fins was investigated. It has been already obtained from the previous study that the fluttering fins were effective for promotion of the jet diffusion. In this paper, the effects of the fin width on the jet diffusion were addressed. The jet flow was visualized by means of the PIV analysis and the LIF method. Moreover, the fin vibration was observed by the high-speed camera. As a result, it has been found that there exists a suitable fin width for the jet diffusion. Furthermore, it has been recognized that the amplitude of the fin vibration becomes smaller and the frequency higher with the decrease of the fin width. And then, the non-axisymmetric vibration appears and the regularity of vibration period weakens.

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Investigation of the characteristics of the jet flow, issuing from a circular pipe and affected by the reciprocal oscillating flows, was addressed in this paper. These reciprocal flows issue from two circular pipes and have the contrary phase each other. Moreover, the net flow rate of the reciprocal flow is zero, respectively. The jet diffusion has been investigated by means of the flow visualization and the PIV analysis. As a result, it has been found that the jet diffusion is affected by these reciprocal oscillating flows largely and is enhanced considerably under the influence of these flows. Furthermore, it has been recognized that the jet flow tends to bifurcate clearly.

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The present paper describes the effect of duct length on acoustic characteristics of over-expanded jet which are discharged from convergent-divergent nozzle. A duct made of annular metal was installed at the nozzle exit and varied in length from 0 and 6D. A Schlieren optical system is used to visualize detailed jet structures. Acoustic measurement is performed to obtain noise spectra. The results obtained show that the frequency of the acoustic tone due to the shock wave within the nozzle somewhat increases with an increase in the nozzle pressure ratio, and the acoustic tones take place in two stages. The duct devices suppress the acoustic tone and the screech tone.

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An experimental study is performed on a composite flow network consisting of a diamond-shaped cylinder bundle sandwiched between two slit flows. A PIV measurement technique is employed to visualize flow phenomena which are recorded by means of a CCD camera. For comparison purpose, a traditional flow channel of rectangular cross section and a composite flow network with a diamond-shaped cylinder bundle in parallel with a slit flow or one side are tested. It is disclosed that the flip-flop flow generated inside the cylinder bundle assists the slit flows to stretch through suppressing the diffusing phenomenon of the efflux jet stream. The mechanisms for the stable efflux stretching are determined..

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Flow characteristics of a two-dimensional jet with curved side walls have been studied experimentally. Four kinds of cylindrical walls were provided as the side walls, and they were combined and attached to a nozzle. Velocity was measured by a hot-wire probe. Mean velocity profiles, the decay of jet maximum velocity, and the growth of the jet half-width were clarified. The maximum velocity decays as the radius of the smaller cylindrical wall becomes large. When the radius of the smaller cylindrical wall exceeds a certain radius, the jet half-width increases suddenly.

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This research executed the stir quenching that generated the circulation convection of the coolant with a motor pump from the pipe set up in the cooling tank bottom part, and did the quenching experiment of Ag and carbon steel SCM420 that evaluated the cooling power. The oil temperature of the coolant was changed from this experiment research in the condition with constant stir speed of the coolant, and the influence that it exerted on cooling the quenching material was observed. It took the dynamic behavior of the appearance of generation and flaking off of the steam film on the surface of the metal when quenching it with a high-speed camera, and the image was achieved, and moreover, the fixed quantity analysis at the flow velocity of the heat flow was done by using the PIV metrology, and making the convection of the steam film and, the coolant visualization was achieved.

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In this research, the gas quenching evaluation device was developed to establish the gas quenching technology, and the PIV system of making to visualization of the thermal flow to clarify the heat transfer behavior in the gas cooling was constructed. And, the cooling curve of the test piece on the surface was measured by the quenching experiments by the gas cooling doing by actually using several kinds of gases, and using the thermo-couple, and the cooling power in the gas cooling process was evaluated.

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The evaluation of the cooling ability of the coolant used for the hardening technology relates to the quality control in the machine part. As for this paper, the cooling capacity of the polymer solution is evaluated with an evaluation device of the coolant that has been used before. In addition, the heat transfer behavior in quenching process is clarified more than making of generation and the destruction of the thermal flow and destruction of the steam film by using the PIV method of visualization.

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To evaluate the sliding behavior of a water droplet on a hydrophobic surface, the analysis system was developed. This system enables continuous and simultaneous measurement of both the sliding acceleration and shape deformation (contact angle, height, length of contact area) during the sliding of the droplet. Moreover, the visualization of the internal fluidity of a sliding droplet was enabled by employing particle image velocimetry in the analysis system.

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Particle tracking velocimetry (PTV) is one of the methods that measure flow velocity fields. This paper proposes a new method that solves the correspondence problem of particle tracking velocimetry using Ant Colony Optimization Algorithm (ACO) that is inspired by co-operative food retrieval in ants. PTV offers many advantages for the study of fluid flows. PTV is formulated as a combinational optimization problem.
Then several PTV algorithms have been proposed which includes algorithms like simulated annealing, genetic algorithms and artificial networks. ACO is a new search metaphor for solving combinational optimization problems and a algorithm as powerful as GA for the combinational optimization problem.
The proposed technique using ACO is applied to the PIV standard images distributed through the web site (http://www.vsj.or.jp/piv). The simulation results demonstrate the effectiveness of the present technique compared with Genetic Algorithm.

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This study is positioned as a basic research for PIV measurement of large spatial airflow using soap bubbles. Bubbles are applied as for airflow tracer because of less environmental impact for the application in nature. The bubble dynamics characteristics are investigated by comparing with smoke-based PIV measurement. The inverse analysis method is constructed to obtain airflow vector field from the bubble vector field, which takes into account the fundamental force components of the bubbles.

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In the relatively small model experiment of river flow, the order of water depth becomes several centimeters and the measurement of mean velocity distribution using probe type instruments becomes difficult. In this research, in order to measure the depth-averaged velocity directly from image analysis, dye injection method is used. As a first step, particle simulation assuming particles moving with different speeds at multiple planes is performed. The PIV result indicates that the obtained velocity almost coincides with the mean velocity.

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The fuzzy logic algorithm has been used for the validation strategy of PTV results. The authors already applied the fuzzy logic model as a particle tracking algorithm with successful results. In this study the basic concept of the fuzzy PTV model seemed no less suitable for the validation strategy of other types of PTV results. The noteworthy point of the fuzzy particle tracking algorithm is the confidence of two adjacent velocity vectors. In the fuzzy PTV this confidence value is updated at each stage of the confidence level estimation between any two adjacent candidate velocity vectors. Similarly the confidence level estimation could be done between any two adjacent velocity vectors resulting from other PTV algorithms. This is the base line of the present new validation strategy.

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At the present day, the varieties of electronic device are advancing miniaturization and high performance. A micro suction nozzle is used to install the miniature electronic parts. In this study, to clarify the transition of suction flow using a micro nozzle of 1.5mm in inner diameter, we visualized the suction flow using tracer particles and measured the flow field using a dynamic particle image velocimetry (PIV).

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The operating range of a centrifugal compressor is usually limited by the choke and the surge. The surge is related to the compressor system but it deeply relates to the inlet stall of impeller and/or the diffuser stall. Here, the velocity distribution in the inlet of a centrifugal impeller was measured using a dynamic PIV system to clarify the stall area at the impeller inlet. The correlations between the swirl flow and the reverse flow were discussed using a stereoscopic PIV system at three typical operating flows such as a stabile flow, an unstable flow and a full stall flow. As a result, the swirl flow appeared with decrease in flow rate owing to the reverse flow in a stall cell.

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A micro laser induced shock wave in a small region was observed by shadowgraph technique. The shock wave was produced on a metal surface when the metal was irradiated by a pulse laser. Titanium and SUS304 was used as the target. The laser used for the irradiation was λ=532nm in wavelength and its irradiation intensity, lo was changed from 630to7690 GW/m2. The flow visualization was carried out by using a laser shadow graphic technique. The shock mach number was calculated from these images. We obtained the shock wave energy conversion coefficient, which is based on Taylor's self-similar analysis. The experimental results showed that the coefficient was 0.08to0.2 for the relatively low irradiation intensity.

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The laser-induced fluorescence method (LIF) has been attracted as an available diagnostic tool for quantitative measurements in wind tunnel testing. Acetone is an ideal tracer material for the LIF method because of low toxicity and its strong fluorescence intensity. Although many studies on the acetone LIF method have been reported, most of these studies are limited to high temperature conditions. In the present study, we investigate the acetone LIF characteristics in low temperature conditions. The 4th harmonic of the Nd:YAG laser (266nm) is used to excite the acetone molecule and the resulting fluorescence intensity is detected by the photomultiplier tube. Nitrogen is selected as a buffer gas. The experimental result reveals that the LIF intensity was almost constant in the present temperature range of 270-300K.

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Crystallization inside micro channel is key technology to making new materials. In order to control the quality of crystal, solubility observation is required. Interferometry is technique to measure solubility using refractive index but it requires complex optical layout. In this paper new technique to measure refractive index inside micro channel using digital holographic technique are proposed. Calculated particle positions are shifted because of variation of refractive index. With this shift, the refractive index inside channel canbe calculated. With simple experiment, feasibility of the technique are confirmed.

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An oscillatory flow was employed to improve the highly effective mixing process in a micro-channel. In the present study, it is clarified on numerically and experimentally that a decrease in frequency and/or an increase in amplitude contribute to increase in the interfacial area between two liquids.

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There is an increasing importance of micro/nano scale flows for the development of MEMS/NEMS (Micro/Nano Electro-Mechanical Systems). The pressure sensitive paint (PSP) technique is considered to be suitable for analyses of these flows in principle. We, therefore, have developed pressure sensitive molecular film(PSMF) based on the Langmuir-Blodgett(LB) technique, which is a method to make high ordered mono-molecular films, to overcome problems of the existing PSP at micro/nano systems. In this study, we adopt two luminophores for the PSMF in order to select the one for low pressure range and the other for near-atmospheric pressure depending on the pressure range of interest. We clarify their fundamental properties such as pressure sensitivity. As a result, it is confirmed that the PSMF with Palladium(II) MesoporphyrinIX (PtMP) is effective in the low pressure range and that with Platinum(II) MesoporphyrinIX (PdMP) is effective in the atmospheric pressure range.

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Since "Kundt's experiment", it has been well known that an acoustic stationary wave in an air column regularly places particles of powdered wood or foamed polystyrene at each loop of the wave in parallel stripes, but no one has never revealed why it makes the particles form a row in stripes. Although the movement of a medium on a stationary wave seems to play a critical role in this phenomenon, there was no visual material filming the clear images of the state of a stationary wave in an air column. The present study has a purpose to investigate and visualize the behavior of a medium on a stationary wave. The procedure of the study was as follows: While an acoustic stationary wave was being generated in an air column filled with cigarette smoke, the micro particles of the smoke were visualized through a laser scanning visualization system and filmed with a high-definition video camera.

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