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Study on Enhancement Effect of Cavitation Caused by HIFU Piezoelectricity Transducer
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作者 Xinnan Fan Changping Zhu +2 位作者 Shichuan He Minglei Shan Jiacai Chen 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期527-529,共3页
An orthogonal ultrasonic irradiation system consisting of HIFU with frequency at 1.05 MHz combined with ultrasound with frequency at 28 kHz was applied in this paper.Effect of cavitation was detected by pH-value measu... An orthogonal ultrasonic irradiation system consisting of HIFU with frequency at 1.05 MHz combined with ultrasound with frequency at 28 kHz was applied in this paper.Effect of cavitation was detected by pH-value measurement and conductance measurement.The result shows that the effect of cavitation caused by ultrasound with frequency at 28 kHz is greatly enhanced by HIFU piezoelectricity transducer with frequency at 1.05 MHz. 展开更多
关键词 HIFU piezoelectricity transducer enhanced cavitation effect orthogonal ultrasonic irradiation
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Effects of Sodium Dodecyl Sulfate on a Single Cavitation Bubble
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作者 Qi Wang Wei-Zhong Chen +1 位作者 Xun Wang Tai-Yang Zhao 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第8期40-43,共4页
Dynamics of a single cavitation bubble in sodium dodecyl sulfate(SDS) aqueous solutions is investigated experimentally and theoretically. The bubble pulsation is measured by a phase-locked integrated imaging techniq... Dynamics of a single cavitation bubble in sodium dodecyl sulfate(SDS) aqueous solutions is investigated experimentally and theoretically. The bubble pulsation is measured by a phase-locked integrated imaging technique,and the ambient radius is obtained by fitting the numerical calculation based on the Rayleigh–Plesset bubble dynamics model to the experimental data. The results show that, under the same driving condition, the ambient radius of the cavitation bubble decreases correspondingly with the increase of SDS concentration within the critical micelle concentration, while the compression ratio of the radius increases, which indicates that the addition of SDS decreases the internal molecular number of the cavitation bubble and increases the power capability of the cavitation bubble. In addition, bubble oscillation increases the concentration of the surfactant molecules on the bubble wall, so that the effect of SDS on a single cavitation bubble is reduced when the SDS concentration is greater than 0.8 m M. 展开更多
关键词 SDS effects of Sodium Dodecyl Sulfate on a Single cavitation Bubble
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Multi-physical Modeling and Adjusting for Ultrasonic Assisted Soft Abrasive Flow Processing
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作者 Yesha Ni Yunfeng Tan Dapeng Tan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第4期111-124,共14页
The polishing efficiency of the soft abrasive flow(SAF)method is low,which is not in line with the concept of carbon emission reduction in industrial production.To address the above issue,a two-phase fluid multi-physi... The polishing efficiency of the soft abrasive flow(SAF)method is low,which is not in line with the concept of carbon emission reduction in industrial production.To address the above issue,a two-phase fluid multi-physics modeling method for ultrasonic-assisted SAF processing is proposed.The acoustics-fluid coupling mechanic model based on the realizable k-ε model and Helmholtz equation is built to analyze the cavitation effect.The results show that the pro-posed modeling and solution method oriented to ultrasonic-assisted SAF processing have better revealed the flow field evolution mechanism.The turbulence kinetic energy at different ultrasonic frequencies and amplitudes is stud-ied.Simulation results show that the ultrasonic vibration can induce a cavitation effect in the constrained flow chan-nel and promote the turbulence intensity and uniformity of the abrasive flow.A set of comparative polishing experiments with or without ultrasonic vibration are conducted to explore the performance of the proposed method.It can be found that the ultrasonic-assisted SAF method can improve the machining efficiency and uniformity,to achieve the purpose of carbon emission reduction.The relevant result can offer a helpful reference for the SAF method. 展开更多
关键词 Soft abrasive flow Ultrasonic vibration cavitation effect Polishing efficiency Turbulent kinetic energy
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Influencing factors on hydrodynamic lubrication failure of upstream pumping mechanical seal 被引量:2
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作者 CHEN Huilong LI Xinwen +4 位作者 WANG Bin WU Qiangbo REN Kunteng LI Tong ZHAO Binjuan 《排灌机械工程学报》 EI CSCD 北大核心 2018年第6期509-516,共8页
Considering the effect of viscosity-temperature relationship and cavitation of micro-scale film,the influencing factors on hydrodynamic lubrication performance of upstream pumping mechanical seal were investigated bas... Considering the effect of viscosity-temperature relationship and cavitation of micro-scale film,the influencing factors on hydrodynamic lubrication performance of upstream pumping mechanical seal were investigated based on the theory of hydrodynamic lubrication.N-S equation,energy equation,viscosity-temperature equation and vapor transport equation were solved with the finite volume method by using Fluent software,which was performed to analyze the influence of the viscosity-temperature and cavitation effect on hydrodynamic lubrication failure of the film.The research demonstrates that it will lead to the significant difference of the temperature field by considering the coupling of temperature and viscosity.When the film thickness decreases and the rotating speed rises,cavitation regions and viscous friction heat increases,the opening force of the film is also enhanced.However,the growth rate is restricted to the cavitation regions and viscous friction heat,and the opening force begins to decline to a certain extent,and thereby being insufficient to open the surfaces of the seals and leading to the failure of automatic adjustment function and severe wear,lubrication failure occurrs.Through comprehensive research on the influences of viscosity-temperature and cavitation effect on hydrodynamic lubrication performance,the theories of failure and design of upstream pumping mechanical seal are further developed. 展开更多
关键词 mechanical seal hydrodynamic lubrication viscosity-temperature effect cavitation effect lubrication failure computational fluid dynamics
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Ultrasound-mediated transdermal drug delivery of fluorescent nanoparticles and hyaluronic acid into porcine skin in vitro 被引量:2
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作者 王焕磊 范鹏飞 +3 位作者 郭霞生 屠娟 马勇 章东 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第12期98-105,共8页
Transdermal drug delivery (TDD) can effectively bypass the first-pass effect. In this paper, ultrasound-facilitated TDD on fresh porcine skin was studied under various acoustic parameters, including frequency, ampli... Transdermal drug delivery (TDD) can effectively bypass the first-pass effect. In this paper, ultrasound-facilitated TDD on fresh porcine skin was studied under various acoustic parameters, including frequency, amplitude, and exposure time. The delivery of yellow-green fluorescent nanoparticles and high molecular weight hyaluronic acid (HA) in the skin samples was observed by laser confocal microscopy and ultraviolet spectrometry, respectively. The results showed that, with the application of ultrasound exposures, the permeability of the skin to these markers (e.g., their penetration depth and concentration) could be raised above its passive diffusion permeability. Moreover, ultrasound-facilitated TDD was also tested with/without the presence of ultrasound contrast agents (UCAs). When the ultrasound was applied without UCAs, low ultrasound frequency will give a better drug delivery effect than high frequency, but the penetration depth was less likely to exceed 200 p.m. However, with the help of the ultrasound-induced microbubble cavitation effect, both the penetration depth and concentration in the skin were significantly enhanced even more. The best ultrasound-facilitated TDD could be achieved with a drug penetration depth of over 600 p.m, and the penetration concentrations of fluorescent nanoparticles and HA increased up to about 4-5 folds. In order to get better understanding of ultrasound-facilitated TDD, scanning electron microscopy was used to examine the surface morphology of skin samples, which showed that the skin structure changed greatly under the treatment of ultrasound and UCA. The present work suggests that, for TDD applications (e.g., nanoparticle drug carriers, transdermal patches and cosmetics), protocols and methods presented in this paper are potentially useful. 展开更多
关键词 transdermal delivery of drugs ultrasound contrast agents pulsed ultrasound cavitation effect
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Numerical simulation on turbulent flow field in convergentdiveroent nozzle 被引量:4
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作者 LU Yi-yu LIU Yongc LI Xiao-hong KANG Yong ZHAO Jian-xin 《Journal of Coal Science & Engineering(China)》 2009年第4期434-439,共6页
Because of the complication of turbulence's mechanism and law as well as the jet pressure in nozzle is difficult to test by experiment, five turbulent models were applied to numerically simulate the turbulent flow fi... Because of the complication of turbulence's mechanism and law as well as the jet pressure in nozzle is difficult to test by experiment, five turbulent models were applied to numerically simulate the turbulent flow field in convergent-divergent nozzle. Theory analysis and experiment results of mass flow rates conclude that the RNG k-ε model is the most suitable model. The pressure distribution in the convergent-divergent nozzle was revealed by computational fluid dynamic (CFD) simulating on the turbulent flow field under different pressure conditions. The growing conditions of cavitation bubbles were shown; meanwhile, the phenomena in the experiment could be explained. The differential pres- sure between the upstream and downstream in nozzle throat section can improve the cavitating effect of cavitation water jet. 展开更多
关键词 numerical simulation convergent-divergent nozzle turbulent flow field cavitation water jet cavitating effect
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Ultrasonic-assisted soldering W90 Tungsten heavy alloy to AZ31B Mg alloy using Sn-x Al alloy
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作者 Xudong Zhang Wei Fu +4 位作者 Xiaoguo Song Liangbo Chen Zhuolin Li Shengpeng Hu Hong Bian 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第8期132-140,共9页
A double-layered W/Mg structure is expected to be a new generation of nuclear radiation shielding material.The tungsten heavy alloy(W90)and AZ31B Mg alloy were firstly bonded by ultrasonic-assisted soldering using pur... A double-layered W/Mg structure is expected to be a new generation of nuclear radiation shielding material.The tungsten heavy alloy(W90)and AZ31B Mg alloy were firstly bonded by ultrasonic-assisted soldering using pure Sn and Sn-Al filler metal in an atmospheric environment.The influence of ultrasonication time on the microstructure and mechanical properties of the joint was investigated.The typical microstructure of the W90/Sn/Mg joint was W90/Mg_(2)Sn+Sn/Mg_(2)Sn layer/Mg.As the ultrasonication time increased from 2 s to 10 s,the joint width reduced and the thickness of the Mg_(2)Sn layer increased.The shear strength of the joint firstly increased,then flattened,and finally decreased.The joint strength reached the maximum value of 10.5 MPa.The fracture position of the joint changed from the W90/filler metal interface to the Mg_(2)Sn layer.The addition of Al in Sn resulted in the formation of the Al4 W phase at the W/Sn-1Al interface.The W/filler metal interface changed from the semi-coherent interface to the coherent interface and the joint strength increased.As the ultrasonication time was 6 s,the shear strength W90/Sn-1Al/Mg joint reached the maximum value of 24.6 MPa and the joint fractured at two positions:W90/filler metal interface and filler metal.With the further increase of ultrasonication time,the joint strength decreased and the joint fractured in the Mg_(2)Sn layer. 展开更多
关键词 Tungsten heavy alloy Mg alloy Ultrasonic-assisted soldering Mg_(2)Sn cavitation effect
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Recent progress of ultrasound-responsive titanium dioxide sonosensitizers in cancer treatment
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作者 Hajing Cui Weihao Zhu +3 位作者 Chuning Yue Ming Yang Wenzhi Ren Aiguo Wu 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第10期63-72,共10页
Sonodynamic therapy(SDT)exhibits promising clinical applications in cancer treatment owing to its ad-vantages,including ultrasonic cavitation effect,mechanical effect,and deep tissue penetration.Titanium dioxide(TiO_(... Sonodynamic therapy(SDT)exhibits promising clinical applications in cancer treatment owing to its ad-vantages,including ultrasonic cavitation effect,mechanical effect,and deep tissue penetration.Titanium dioxide(TiO_(2))nanomaterials,recognized as excellent sonosensitizers,have been extensively studied in cancer SDT.This review first outlines the mechanism of TiO_(2)-based SDT,then systematically discusses the regulation of TiO_(2) sonosensitivity,covering aspects such as morphology,particle size,element doping,defect engineering,heterojunction structure,and interactions with the tumor microenvironment.Further-more,the review generalizes ultrasound-responsive TiO_(2)-based therapeutic modalities for tumor treat-ment,including SDT,SDT combined with chemotherapy,chemodynamic therapy,photothermal therapy,immunotherapy,and treatment visualization.Finally,the review navigates the ongoing challenges and prospects in TiO_(2)-based cancer SDT. 展开更多
关键词 Titanium dioxide Sonodynamic therapy Reactive oxygen species cavitation effects Combined therapy
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CACA guidelines for ultrasound hyperthermia for oral and maxillofacial head and neck squamous cell carcinoma
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作者 Houyu Ju Jiawei Zheng +16 位作者 Moyi Sun Zhangui Tang Daoke Yang Wei Ran Zhijun Sun Wei Shang Jian Meng Heming Wu Qing Xi Kai Yang Jun Wang Li Huang Jiaxuan Qiu Yunteng Wu Guoxin Ren Zhifei Dai Wei Guo 《Holistic Integrative Oncology》 2023年第1期101-107,共7页
Most of the patients with oral and maxillofacial malignancy are in the middle and advanced stages at diagnosis and the incidence rate is increasing in recent years.Chemotherapy alone is difficult to benefit the surviv... Most of the patients with oral and maxillofacial malignancy are in the middle and advanced stages at diagnosis and the incidence rate is increasing in recent years.Chemotherapy alone is difficult to benefit the survival of patients with advanced oral and maxillofacial malignancy.Ultrasound hyperthermia is a new and effective treatment for malignant tumor,which is developing rapidly in addition to conventional treatment.However,at present,ultrasound hyperthermia has not been widely used in the treatment of oral and maxillofacial malignancy.Therefore,formation of a guideline on ultrasound hyperthermia for oral and maxillofacial malignancy is mandatory,in order to promote and standardize the clinical practice of ultrasound hyperthermia in this field,and improve the long-term survival rate and quality of life of patients. 展开更多
关键词 Oral and maxillofacial malignancy Ultrasound hyperthermia Combination therapy cavitation effect GUIDELINE
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