A method for identification of analyte concentration in aqueous solution by using a mistuned fluid-structure coupled vibration

2021 ◽  
Vol 35 (2) ◽  
pp. 481-486
Author(s):  
Yugang Chen ◽  
Kang-Jae Park ◽  
Bomi Lee ◽  
Yong-Hwa Park
Keyword(s):  
Aqueous Solution ◽  
Analyte Concentration ◽  
Coupled Vibration ◽  
Fluid Structure

Experimental Study of Coupling Vibration Characteristics Between a Thin Cylindrical Water Storage Tank and Its Contained Liquid

2005 ◽  
Author(s):  
Akira Maekawa ◽  
Yasutaka Shimizu ◽  
Michiaki Suzuki ◽  
Katsuhisa Fujita
Keyword(s):  
Storage Tank ◽  
Excitation Frequency ◽  
Fluid Pressure ◽  
Water Storage ◽  
Fem Analysis ◽  
Shaking Table ◽  
Vibration Modes ◽  
Coupled Vibration ◽  
Fluid Structure ◽  
Water Storage Tank

A large cylindrical water storage tank typically has a thin sidewall. When such a tank is under an earthquake, the vibrations of the water inside are coupled with the vibrations of the sidewall, producing a phenomenon called fluid-structure coupled vibration. The fluid-structure coupled vibration is an important issue for a tank like this to achieve reasonable seismic-proof design. Even though there have been many studies on fluid-structure coupled vibrations, only a few of them have examined the dynamic fluid pressure and oval vibrations. This paper reports on the investigations into the characteristics of oval vibrations exhibited by a cylindrical water storage tank, in which a vibration test was conducted using a shaking table, the correlation of changes in the excitation force and behaviors of dynamic fluid pressure with the appearance and growth of oval vibrations were analyzed, and the modes of oval vibrations that appeared were identified. The vibration test was conducted using a scale model tank of a large cylindrical water storage tank and a shaking table. The input vibrations were sinusoidal waves of 53 Hz, a frequency that was in the vicinity of the resonance frequency. The test took the form of a large amplitude excitation test, which increased the acceleration of the input vibrations gradually. The response acceleration of the tank and the dynamic fluid pressure were measured. Strain gages attached around the trunk of the tank were used to identify oval vibration modes. The frequency analysis of the dynamic fluid pressure revealed two major peaks, one at 53 Hz which matched the excitation frequency and the other at 106 Hz which was double the excitation frequency. It showed that the dynamic fluid pressure has nonlinear behavior like higher-harmonic resonance. The frequency analysis of the responses on the trunk of the tank arising from oval vibrations also revealed two major peaks, one at 53Hz and the other at 106Hz. The behavior of dynamic fluid pressure and the behavior of oval vibrations were coupled. It was found that a certain magnitude of the response acceleration of the tank that gave rise to oval vibrations were in proportion to the rate of increase of the response acceleration of the tank. In other words, oval vibrations appeared at a relatively low response acceleration if the response acceleration increased slowly, whereas oval vibrations appeared only at a relatively high response acceleration if the response acceleration increased quickly. An analysis of the circumferential distribution of circumferential strains around the trunk of the tank revealed the presence of two oval vibration modes with different circumferential wave numbers: 14 and 16, which have not been predicted by the FEM analysis. None of the natural frequencies determined by the FEM analysis of the two different vibration modes matched 106 Hz; however, a half of the sum of the two natural frequencies was close to 106 Hz. Thus oval vibrations were found to have a nonlinear characteristics experimentally.

Influence of Material Properties on Modal Characteristics for Fluid-Structure Coupled Vibration System

2012 ◽  
Vol 503-504 ◽  
pp. 1086-1089
Author(s):  
Lin Zhu ◽  
Chun Yan Zhu ◽  
De Yuan Xu ◽  
Guo An Tang
Keyword(s):  
Material Properties ◽  
Vibration System ◽  
Coupled Vibration ◽  
Modal Frequency ◽  
Fluid Structure ◽  
Modal Characteristics ◽  
Fem Method ◽  
Frequency Comparison ◽  
Control Equation ◽  
Node Displacement

The analysis processing for the linear coupled vibration of a flume and its inner fluid often uses FEM method. An equation set which contained the fluid node pressure and the structure node displacement is formed, based on this equation, reduction form and symmetry form is used to get the same modal frequency. Computers can calculate out the frequency more rapidly by a smaller control equation. According to the frequency comparison of different fluid-structure coupled vibration system with different materials, this paper draws some conclusions on the influence of material properties on modal characteristics for fluid-structure coupled vibration system. It can give a reference to select the material in practical engineer.

Dynamics Analysis and Simulation for Fluid-Structure Coupled Vibration of Liquid Container

2012 ◽  
Vol 562-564 ◽  
pp. 1028-1031
Author(s):  
Lin Zhu ◽  
Chun Yan Zhu ◽  
Guo An Tang
Keyword(s):  
Stiffness Matrix ◽  
Vibration System ◽  
Coupled Vibration ◽  
Coupling Matrix ◽  
Fluid Structure ◽  
Analysis Process ◽  
Fem Method ◽  
Symmetrical Form ◽  
New Equation ◽  
Node Displacement

The analysis process for the linear coupled vibration of a circular container and its inner liquid often uses FEM method. An equation set which contained the fluid node pressure and the structure node displacement was formed, based on these equations, in this paper, a new equation set which has a smaller dimension and symmetrical form is obtained by the method of model reduction and coordinate symmetrization. By solving the boundary value problems of equivalent Laplace formulas, the additional masses matrix, additional stiffness matrix and coupling matrix which have effect from fluid to structure are gained. The example of the modal analysis for liquid container demonstrates that this method presented in this paper can get the modal frequency accurately and rapidly in fluid-structure coupled vibration system and other similar engineering realm.

scholarly journals An Analysis of Fluid Structure Coupled Vibration Considering Modal Added Mass.

1994 ◽  
Vol 60 (571) ◽  
pp. 743-748 ◽  
Author(s):  
Masayuki Kasahara ◽  
Hiroshi Ishii ◽  
Michiyuki Takagi ◽  
Kazutoshi Kawamoto
Keyword(s):  
Added Mass ◽  
Coupled Vibration ◽  
Fluid Structure

Microtube flowing coulometry

1994 ◽  
Vol 72 (3) ◽  
pp. 836-849 ◽  
Author(s):  
Lifeng Chen ◽  
Christa L. Colyer ◽  
Muthoni G. Kamau ◽  
Jan C. Myland ◽  
Keith B. Oldham ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Steady State ◽  
Residence Time ◽  
Tube Wall ◽  
Supporting Electrolyte ◽  
Small Concentration ◽  
Analyte Concentration ◽  
Flow Conditions ◽  
Experimental Realization ◽  
Measured Flow

An aqueous solution containing supporting electrolyte and a small concentration of an electroactive analyte is allowed to flow, under a gravitational head, through a polarized platinum tube. The tube is narrow enough that, during their few seconds of residence time within the tube, virtually all the analyte molecules are able to diffuse to the tube wall and be electrolytically destroyed. The analyte concentration is accurately calculable, when the applied voltage and head are optimized, from the measured flow rate of the solution and the steady-state electric current, the latter being background-corrected by subtracting the current under no-flow conditions. Though the detailed theory is complicated, the principles of the method and its experimental realization are straightforward.

Coupled Vibration Analysis of a Fluid-Filled Pipe by Wavenumber Prediction

2010 ◽  
Vol 34-35 ◽  
pp. 951-955
Author(s):  
Jin Yan ◽  
Shi Liang Zhang ◽  
Juan Zhang
Keyword(s):  
Structure Analysis ◽  
Vibration Analysis ◽  
Wave Motion ◽  
Numerical Results ◽  
Coupled Vibration ◽  
Low Frequencies ◽  
Fluid Structure ◽  
Axisymmetric Wave ◽  
The Stability ◽  
Axial Waves

The stability and vibration of fluid-filled pipes are important in many engineering situations and have been extensively studied. In this paper, coupled fluid–structure analysis is carried on by wavenumber prediction. Pipe equations for axisymmetric wave motion are derived, and two kind of axial waves are studied analytically at low frequencies, i.e., , which is a predominantly fluid-borne wave, and , is predominantly a shell wave. Numerical results are subsequently given to show the definitely influence of the pipe and the fluid.

Structures Formed by Cryoprotective Agents Used in Freezc-Etching

1971 ◽  
Vol 29 ◽  
pp. 448-449
Author(s):  
G. G. Cocks ◽  
C. E. Cluthe
Keyword(s):  
Aqueous Solution ◽  
Polyethylene Oxide ◽  
Liquid Nitrogen Temperature ◽  
Ice Crystals ◽  
Etching Technique ◽  
Structural Constituent ◽  
Cryoprotective Agents ◽  
Quick Freezing ◽  
Freeze Etching ◽  
Fractured Surface

The freeze etching technique is potentially useful for examining dilute solutions or suspensions of macromolecular materials. Quick freezing of aqueous solutions in Freon or propane at or near liquid nitrogen temperature produces relatively large ice crystals and these crystals may damage the structures to be examined. Cryoprotective agents may reduce damage to the specimem, hut their use often results in the formation of a different set of specimem artifacts.In a study of the structure of polyethylene oxide gels glycerol and sucrose were used as cryoprotective agents. The experiments reported here show some of the structures which can appear when these cryoprotective agents are used.Figure 1 shows a fractured surface of a frozen 25% aqueous solution of sucrose. The branches of dendritic ice crystals surrounded hy ice-sucrose eutectic can be seen. When this fractured surface is etched the ice in the dendrites sublimes giving the type of structure shown in Figure 2. The ice-sucrose eutectic etches much more slowly. It is the smooth continuous structural constituent surrounding the branches of the dendrites.

Preparation and characterisation of vanadium pentoxide supported rhodium catalyst

1988 ◽  
Vol 46 ◽  
pp. 946-947
Author(s):  
A. Legrouri
Keyword(s):  
Aqueous Solution ◽  
Thermal Decomposition ◽  
Physicochemical Properties ◽  
Surface Area ◽  
Vanadium Pentoxide ◽  
High Purity ◽  
Gas Adsorption ◽  
Rhodium Catalyst ◽  
Optical Methods ◽  
Reducible Oxides

The industrial importance of metal catalysts supported on reducible oxides has stimulated considerable interest during the last few years. This presentation reports on the study of the physicochemical properties of metallic rhodium supported on vanadium pentoxide (Rh/V2O5). Electron optical methods, in conjunction with other techniques, were used to characterise the catalyst before its use in the hydrogenolysis of butane; a reaction for which Rh metal is known to be among the most active catalysts.V2O5 powder was prepared by thermal decomposition of high purity ammonium metavanadate in air at 400 °C for 2 hours. Previous studies of the microstructure of this compound, by HREM, SEM and gas adsorption, showed it to be non— porous with a very low surface area of 6m2/g3. The metal loading of the catalyst used was lwt%Rh on V2Q5. It was prepared by wet impregnating the support with an aqueous solution of RhCI3.3H2O.

TEM observation of iron oxide pillars in montmorillonite

1990 ◽  
Vol 48 (4) ◽  
pp. 882-883
Author(s):  
H. Mori ◽  
Y. Murata ◽  
H. Yoneyama ◽  
H. Fujita
Keyword(s):  
Aqueous Solution ◽  
Iron Oxide ◽  
Fine Particles ◽  
Aqueous Suspension ◽  
Volume Ratio ◽  
Exchange Capacity ◽  
Nano Composites ◽  
Pillared Montmorillonite ◽  
Topographic Features ◽  
Transmission Electron

Recently, a new sort of nano-composites has been prepared by incorporating such fine particles as metal oxide microcrystallites and organic polymers into the interlayer space of montmorillonite. Owing to their extremely large specific surface area, the nano-composites are finding wide application[1∼3]. However, the topographic features of the microstructures have not been elucidated as yet In the present work, the microstructures of iron oxide-pillared montmorillonite have been investigated by high-resolution transmission electron microscopy.Iron oxide-pillared montmorillonite was prepared through the procedure essentially the same as that reported by Yamanaka et al. Firstly, 0.125 M aqueous solution of trinuclear acetato-hydroxo iron(III) nitrate, [Fe3(OCOCH3)7 OH.2H2O]NO3, was prepared and then the solution was mixed with an aqueous suspension of 1 wt% clay by continuously stirring at 308 K. The final volume ratio of the latter aqueous solution to the former was 0.4. The clay used was sodium montmorillonite (Kunimine Industrial Co.), having a cation exchange capacity of 100 mequiv/100g. The montmorillonite in the mixed suspension was then centrifuged, followed by washing with deionized water. The washed samples were spread on glass plates, air dried, and then annealed at 673 K for 72 ks in air. The resultant film products were approximately 20 μm in thickness and brown in color.

The microstructure of functionalized poLyacrylonitrile beads for bioseparations

1990 ◽  
Vol 48 (4) ◽  
pp. 1094-1095
Author(s):  
Eduardo A. Kamenetzky ◽  
David A. Ley
Keyword(s):  
Aqueous Solution ◽  
Affinity Chromatography ◽  
Pore Size Distribution ◽  
Pore Size ◽  
Surface Coverage ◽  
Vacuum Impregnation ◽  
Thin Sections ◽  
Selective Staining ◽  
Low Viscosity ◽  
Diamond Knife

The microstructure of polyacrylonitrile (PAN) beads for affinity chromatography bioseparations was studied by TEM of stained ultramicrotomed thin-sections. Microstructural aspects such as overall pore size distribution, the distribution of pores within the beads, and surface coverage of functionalized beads affect performance properties. Stereological methods are used to quantify the internal structure of these chromatographic supports. Details of the process for making the PAN beads are given elsewhere. TEM specimens were obtained by vacuum impregnation with a low-viscosity epoxy and sectioning with a diamond knife. The beads can be observed unstained. However, different surface functionalities can be made evident by selective staining. Amide surface coverage was studied by staining in vapor of a 0.5.% RuO4 aqueous solution for 1 h. RuO4 does not stain PAN but stains, amongst many others, polymers containing an amide moiety.

Sign in / Sign up

Export Citation Format

Share Document