scholarly journals Validation of Nanoparticle Response to the Sound Pressure Effect during the Drug-Delivery Process

Polymers ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 186 ◽  
Author(s):  
Mohamed Abbas ◽  
Mohammed Alqahtani ◽  
Ali Algahtani ◽  
Amir Kessentini ◽  
Hassen Loukil ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Sound Pressure ◽  
Pressure Effect ◽  
Experimental Results ◽  
Sound Waves ◽  
Subcutaneous Injections ◽  
Acrylic Plastic ◽  
Sound Pressure Levels ◽  
The Impact ◽  
Interaction Behaviors

Intravenous delivery is the fastest conventional method of delivering drugs to their targets in seconds, whereas intramuscular and subcutaneous injections provide a slower continuous delivery of drugs. In recent years, nanoparticle-based drug-delivery systems have gained considerable attention. During the progression of nanoparticles into the blood, the sound waves generated by the particles create acoustic pressure that affects the movement of nanoparticles. To overcome this issue, the impact of sound pressure levels on the development of nanoparticles was studied herein. In addition, a composite nanostructure was developed using different types of nanoscale substances to overcome the effect of sound pressure levels in the drug-delivery process. The results demonstrate the efficacy of the proposed nanostructure based on a group of different nanoparticles. This study suggests five materials, namely, polyimide, acrylic plastic, Aluminum 3003-H18, Magnesium AZ31B, and polysilicon for the design of the proposed structure. The best results were obtained in the case of the movement of these molecules at lower frequencies. The performance of acrylic plastic is better than other materials; the sound pressure levels reached minimum values at frequencies of 1, 10, 20, and 60 nHz. Furthermore, an experimental setup was designed to validate the proposed idea using advanced biomedical imaging technologies. The experimental results demonstrate the possibilities of detecting, tracking, and evaluating the movement behaviors of nanoparticles. The experimental results also demonstrate that the lowest sound pressure levels were observed at lower frequency levels, thus proving the validity of the proposed computational model assumptions. The outcome of this study will pave the way to understand the interaction behaviors of nanoparticles with the surrounding biological environments, including the sound pressure effect, which could lead to the useof such an effect in facilitating directional and tactic movements of the micro- and nano-motors.

Damage of the Auditory System Associated with Acute Blast Trauma

1989 ◽  
Vol 98 (5_suppl) ◽  
pp. 23-34 ◽  
Author(s):  
Michele Roberto ◽  
Roger P. Hamernik ◽  
George A. Turrentine
Keyword(s):  
Auditory System ◽  
Sound Pressure ◽  
Basilar Membrane ◽  
Organ Of Corti ◽  
Blast Waves ◽  
Mechanical Fracture ◽  
Sound Pressure Levels ◽  
Temporal Bones ◽  
Blast Trauma ◽  
The Impact

This paper reviews the results of several studies on the effects of blast wave exposure on the auditory system of the chinchilla, the pig, and the sheep. The chinchillas were exposed at peak sound pressure levels of approximately 160 dB under well-controlled laboratory conditions. A modified shock tube was used to generate the blast waves. The pigs and sheep were exposed under field conditions in an instrumented hard-walled enclosure. Blast trauma was induced by the impact of a single explosive projectile. The peak sound pressure levels varied between 178 and 209 dB. All animals were killed immediately following exposure, and their temporal bones were removed for fixation and histologic analysis using light microscopy and scanning electron microscopy. Middle ears were examined visually for damage to the conductive system. There were well-defined differences in susceptibility to acoustic trauma among species. However, common findings in each species were the acute mechanical fracture and separation of the organ of Corti from the basilar membrane, and tympanic membrane and ossicular failure.

scholarly journals Impact of a participatory program to reduce noise in a Neonatal Unit

2012 ◽  
Vol 20 (1) ◽  
pp. 109-116 ◽  
Author(s):  
Nelma Ellen Zamberlan-Amorim ◽  
Cristina Ide Fujinaga ◽  
Vanderlei José Hass ◽  
Luciana Mara Monti Fonseca ◽  
Cinira Magali Fortuna ◽  
...  
Keyword(s):  
Intervention Program ◽  
Sound Pressure ◽  
Statistical Tests ◽  
Neonatal Unit ◽  
University Hospital ◽  
Sound Pressure Levels ◽  
Before And After ◽  
Quasi Experimental ◽  
Level Of Significance ◽  
The Impact

This study evaluated the impact of a participatory program to reduce noise in a neonatal intermediate care unit of a university hospital. A time-series quasi-experimental design was used, in which sound pressure levels were measured before and after the intervention was implemented using the Quest-400 dosimeter. Non-parametric statistical tests were used to compare noise with the level of significance fixed at 5%. Results showed significant reduction of sound pressure levels in the neonatal unit after the intervention program was implemented (p<0.0001). The average Leq before the intervention was 62.5dBA and was reduced to 58.8dBA after the intervention. A reduction of 7.1dBA in the average Lmax(from 104.8 to 87.7dBA) and of 30.6dBA in the average Lpeak(from 138.1 to 107.5dBA) was observed. The program was proven to be effective in significantly reducing noise levels in the neonatal unit, although levels were still more intense than recommended.

Investigation on collision-coalescence of droplets under the synergistic effect of charge and sound waves: orthogonal design optimization

2021 ◽  
Author(s):  
Fuyou He ◽  
li jiawei_hust ◽  
Chuan Li ◽  
Pengyu Wang ◽  
Zutao Wang ◽  
...  
Keyword(s):  
Sound Pressure Level ◽  
Sound Pressure ◽  
Orthogonal Design ◽  
Pressure Level ◽  
Collision Probability ◽  
Droplet Growth ◽  
Sound Waves ◽  
Growth Ratio ◽  
Acoustic Frequency ◽  
The Impact

Abstract As an efficient approach to improve the visibility, defogging technology is essential for the operation of ports and airports. This paper proposes a new and hybrid defogging technology, i.e. electric–acoustic defogging method. Specifically, the droplets are charged by corona discharge, which is beneficial to overcome the hydrodynamic interaction force to improve the droplet collision efficiency. Meanwhile, sound waves (especially acoustic turbulence) promote the relative movement of droplets to increase the collision probability. In this study, the effects of acoustic frequency ( f ), sound pressure level (SPL), and voltage (V) on the droplet growth ratio were studied by orthogonal design analysis. The results of difference analysis and multi-factor variance analysis show that frequency and sound pressure level are the dominant factors that affect the collision of droplets, and the effect of voltage is relatively weak. And f = 400 Hz, SPL = 132 dB, and V = -7.2 kV are the optimal parameters in our experiment. In addition, we further studied the impact of single factor on droplet growth ratio. The results show that there is an optimal frequency of 400 Hz. That is, the impact of frequency is non-linear. The droplet growth ratio increases with sound pressure level and voltage level. The new technology proposed in this paper can provide a new approach for defogging in open space.

Experimental Investigation of the Influence of the Shear Layer on Direct Combustion Noise of a Turbulent Jet Flame

2017 ◽  
Author(s):  
Holger Nawroth ◽  
Christian Oliver Paschereit
Keyword(s):  
Shear Layer ◽  
Sound Pressure ◽  
Shear Layers ◽  
Combustion Noise ◽  
Layer Width ◽  
Jet Flame ◽  
Turbulent Fluctuations ◽  
Direct Combustion ◽  
Sound Pressure Levels ◽  
The Impact

This work presents results from experiments on direct combustion noise emitted from an unconfined, turbulent, premixed jet flame. It focuses on the influence of the shear layer and the turbulent fluctuations within this layer on the resulting noise emissions. Orifice discs of different diameter are used to change the shear layer width of the emanating jet. Using these discs, which induce and increase blockage upstream of the reaction zone, leads to significantly higher turbulent fluctuations of the velocity and subsequently to wider shear layers. As these fluctuations in the shear layer are the origin of direct combustion noise, the sound pressure levels of reacting flows increase as well. Moreover, the experiments also show the impact of the Reynolds number and equivalence ratio on noise emissions when using these discs. In general, wider shear layers yield higher sound pressure levels of the resulting combustion noise. Although amplitudes of the resulting noise emissions might differ for different conditions, the normalized sound spectra coincide proving that turbulent velocity fluctuations only govern the sound pressure levels but do not affect the shape of the resulting spectra if the geometry and fuel remain the same.

Using Ceramic Balls to Reduce Noise in a Linear Guideway Type Recirculating Linear Ball Bearing

2003 ◽  
Vol 125 (3) ◽  
pp. 480-486 ◽  
Author(s):  
Hiroyuki Ohta ◽  
Takumi Nakagawa
Keyword(s):  
Sound Pressure Level ◽  
Sound Pressure ◽  
Ball Bearing ◽  
Pressure Level ◽  
Linear Velocity ◽  
Sound Frequency ◽  
Experimental Results ◽  
New Method ◽  
Sound Pressure Levels ◽  
Steel Balls

A new method of reducing the noise of the linear guideway type recirculating linear ball bearing (linear bearing) was studied. In the experiments, the overall sound pressure levels of linear bearings with steel balls or ceramic Si3N4 balls were measured, and sound frequency analyses were carried out. Moreover, based on the assumption that the main cause of the noise may be the collision between the ball and the carriage, the overall sound pressure levels of the linear bearings were analyzed combining the Hertzian theory and the results of previous studies on collision sound. From the results of experiments and analyses, the conclusions were obtained as follows: (1) The overall sound pressure level of the linear bearing with steel balls can be reduced by about 4.5 dB by using Si3N4 balls having the same diameter; (2) The overall sound pressure levels of linear bearings with steel balls or ceramic Si3N4 balls were both increased by about 9.8 dB as the linear velocity increased an octave; and (3) The analytical results, based on the assumption that the main cause of the noise emitted from the linear bearings is the collision between the ball and the carriage, match the experimental results well.

scholarly journals Effect of Tailing-Edge Thickness on Aerodynamic Noise for Wind Turbine Airfoil

Energies ◽  
2019 ◽  
Vol 12 (2) ◽  
pp. 270 ◽  
Author(s):  
Xinkai Li ◽  
Ke Yang ◽  
Hao Hu ◽  
Xiaodong Wang ◽  
Shun Kang
Keyword(s):  
Wind Turbine ◽  
Sound Pressure ◽  
Low Frequency ◽  
Experimental Results ◽  
Aerodynamic Noise ◽  
Calculation Methods ◽  
Trailing Edge ◽  
Eddy Simulation ◽  
Wind Turbine Airfoil ◽  
The Impact

The influence of wind turbine airfoil trailing edge thickness on aerodynamics and aerodynamic noise characteristics was studied using the computational fluid dynamics (CFD)/ Ffowcs Williams–Hawkings (FW–H) method in the present work. First, the airfoil of a DU97-W-300-flatback airfoil was chosen as the research object, and numerical method validation was performed. Three kinds of turbulence calculation methods (unsteady Reynolds average Navier-Stokes (URANS), detached eddy simulation (DES), and large eddy simulation (LES)) were investigated in detail, and three sets of grid scales were used to study the impact of the airfoil on the aerodynamic noise. Secondly, the airfoil trailing edge thickness was changed, and the impact of trailing edge thickness on aerodynamics and aerodynamic noise was investigated. Results show that three kinds of turbulence calculation methods yield the same sound pressure frequency, and the magnitude of the sound pressure level (SPL) corresponding to the mean frequency is almost the same. The calculation of the SPL of the peak value and the experimental results can match well with each other, but the calculated core frequency is slightly lower than the experimental frequency. The results of URANS and DES are closer to each other with a changing trend of SPL, and the consequences of the DES calculation are closer to the experimental results. From the comparison of two airfoils, the blunt trailing edge (BTE) airfoil has higher lift and drag coefficients than the original airfoil. The basic frequency of lift coefficients of the BTE airfoil is less than that of the original airfoil. It is demonstrated that the trailing vortex shedding frequency of the original airfoil is higher than that of the BTE airfoil. At a small angle of attack (AOA), the distribution of SPL for the original airfoil exhibits low frequency characteristics, while, at high AOA, the wide frequency characteristic is presented. For the BTE airfoil, the distribution of SPL exhibits low frequency characteristics for the range of the AOA. The maximum AOA of SPL is 4° and the minimum AOA of SPL is 15°, while, for the original airfoil, the maximum AOA of SPL is 19°, and the minimum AOA is 8°. For most AOAs, the SPL of the BTE airfoil is larger than that of the original airfoil.

Analysis of Impact Noise of Nail Ejection in Wire Nail Machines

1999 ◽  
Author(s):  
Jack Ding ◽  
Ahmed Al-Jumaily ◽  
Doug Wilson
Keyword(s):  
Sound Pressure ◽  
High Frequencies ◽  
Impact Noise ◽  
Press Forming ◽  
Large Force ◽  
Ejection Force ◽  
Sound Pressure Levels ◽  
High Level ◽  
The Impact ◽  
Punch Press

Abstract A wire nail production machine can be classified as one of the punch press machines. By nature, the production of wire nails involves the development of a series of force impulses which in turn generate various sound pressure levels with different frequencies. Typically, the machine operations generating impact noise include pressing, cutting, ejecting, wire gripping and feeding. The punch pressing is the movement of punch header to press forming the nail head. It produces a large force impulse which in turn generates a high level of impact noise and consequently high levels of ancillary impact noise such as the impact noise by the backlashes. It has been found that this type of impact noise is not necessarily the most annoying one. The impact noise generated by nail ejection, however, has been identified as one of the annoying noise components. The ejector used in a nail machine for executing the movement of nail ejection produces ringing noise at high frequencies when it is struck by the punch header in each cycle of the machine operations. This paper presents the analyses of and experiments on the ejection force impulse and the characteristics of the impact noise generated by nail ejection.

scholarly journals ANALYSIS OF THE EXPERIMENTAL STUDY OF THE AXLE LATHE MACHINE VIBROACOUSTIC CHARACTERISTICS FOR WORKPLACE NOISE REDUCTION

Akustika ◽  
2019 ◽  
Vol 34 ◽  
pp. 104-106
Author(s):  
Alexander Shashurin ◽  
Marat Goguadze ◽  
Elkin Yuriy ◽  
Konstantin Buzhinskiy
Keyword(s):  
Experimental Study ◽  
Theoretical Analysis ◽  
Sound Pressure ◽  
Cutting Tool ◽  
Sound Radiation ◽  
Noise Levels ◽  
Sound Pressure Levels ◽  
Lathe Machine ◽  
The Impact ◽  
Workplace Noise

The purpose of this study is to measure the octave sound pressure levels and vibrations of a stanopod lathe. A theoretical analysis of the sound pressure levels near the osteoprosche machines has been performed. The results of measurements are given. It is obtained that the levels of sound pressure at the workplace exceed sanitary standards. This suggests that the increased noise levels are due to the impact of the sound radiation of the cutting tool and the axis being machined.

scholarly journals Assessing Wind Impact on Noise Level Measurements for Application in Architectural Acoustics: A Preliminary Study

2021 ◽  
Vol 5 (2) ◽  
pp. 413-419
Author(s):  
M. Ocholi ◽  
K.E. Ibe ◽  
E.E. Iheonu ◽  
E.E. Ameh
Keyword(s):  
Wind Speed ◽  
Noise Level ◽  
Sound Pressure ◽  
Wind Effect ◽  
Average Wind Speed ◽  
Architectural Acoustics ◽  
Wind Speeds ◽  
Sound Pressure Levels ◽  
Preliminary Study ◽  
The Impact

In this study, we have used wind data obtained from an earlier work covering several locations in Nigeria to estimate the possible impact of wind on sound pressure levels. Estimated Weibull parameters were used to compute the most probable wind speed, the average wind speed and the duration for which wind speed exceeds or equal the most probable speed. Adopting the proposed criteria that wind is able to strengthen or weaken sound pressure levels by 3dB depending on wind direction, the effect of wind on sound pressure level was determined. Results showed that wind effect seemed more predominant for the sub-sahelian stations such as Sokoto, Kano, and Maiduguri where the impact was found to be +/- 3dB obviously due to the characteristic high wind speeds recorded at those stations. The situation is almost the same for the midland region except that moderate impacts were found in some of the stations like Yola, Yelwa and Bauchi. However, moderate wind impacts generally characterize the Guinea Savannah and the coastal regions with the exception of Enugu with an impact of +/- 3dB. The result for Warri was found to be insignificant. It was concluded that most locations within the Nigerian environment may attain the wind conditions that would necessitate an adjustment in noise level measurements for application in architectural acoustics. In order to further validate the results of this preliminary study, it was recommended that detailed field survey where all relevant parameters such as wind speeds, wind directions and noise levels are simultaneously measured be conducted.

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