In general,the rapid growth of α-Fe clusters is a challenge in high Fe-content Fe-based amorphous alloys,negatively affecting their physical properties.Herein,we introduce an efficient and rapid post-treatment techni...In general,the rapid growth of α-Fe clusters is a challenge in high Fe-content Fe-based amorphous alloys,negatively affecting their physical properties.Herein,we introduce an efficient and rapid post-treatment technique known as ultrasonic vibration rapid processing(UVRP),which enables the formation of high-density strong magnetic α-Fe clusters,thereby enhancing the soft magnetic properties of Fe_(78)Si(13)B_(9) amorphous alloy ribbon.展开更多
As light metals,aluminum and magnesium have been widely used in automotive manufacturing,but the welding of Al/Mg joints is facing challenges.However,it is difficult to obtain high-quality aluminum/magnesium joints wi...As light metals,aluminum and magnesium have been widely used in automotive manufacturing,but the welding of Al/Mg joints is facing challenges.However,it is difficult to obtain high-quality aluminum/magnesium joints with traditional arc welding methods.As a solid-phase welding technology,ultrasonic metal welding has the characteristics of high welding efficiency and less welded defects.It is also suitable for welding sound metal bonds.Aluminum and magnesium ultrasonic welding has become a research hotspot.Therefore,the evolution of microstructures and mechanical performance of Al/Mg and multi-layer Al/Mg ultrasonic welding,and the new study works,including the molecular dynamic simulation of Al/Mg ultrasonic welding and hybrid based on ultrasonic welding are summarized.Furthermore,several promising research directions are proposed to guide in-depth investigations into the ultrasonic welding of Al/Mg dissimilar joints.展开更多
Ultrasonic elliptical vibration cutting(UEVC)with clockwise elliptical vibration has made notable achievements in precision machining;however,its critical cutting speed limits its application to low-speed machining ta...Ultrasonic elliptical vibration cutting(UEVC)with clockwise elliptical vibration has made notable achievements in precision machining;however,its critical cutting speed limits its application to low-speed machining tasks.Meanwhile,rotary ultrasonic elliptical machining(RUEM)with clockwise elliptical vibration has been validated as an effective high-speed cutting technology.Unfortunately,conventional RUEM leads to increased surface roughness.To address this issue and enhance machining quality,we propose a novel RUEM method employing an anticlockwise vibration direction,called anticlockwise rotary ultrasonic elliptical machining(ARUEM).The mechanisms of surface formation and subsurface strengthening for ARUEM are analyzed.Experimental validations were performed on Ti-6Al-4V alloy,revealing that ARUEM achieved substantially lower ridge heights and up to a 50%reduction in surface roughness compared to conventional RUEM.Additionally,relative to conventional milling,ARUEM resulted in up to 122.6%thicker plastic deformation layers,53.4%higher surface residual compressive stress,and 19.3%greater surface micro-hardness.This study showcases a promising method for high-performance milling of Ti-6Al-4V,offers new insights into RUEM by examining the influence of vibration direction,and enhances understanding of surface formation and subsurface strengthening in the ARUEM method.展开更多
Effects of ultrasonic bonding parameters on atomic diffusion, microstructure at the Al-Au interface, and shear strength of Al-Au ultrasonic bonding were investigated by the combining experiments and finite element (FE...Effects of ultrasonic bonding parameters on atomic diffusion, microstructure at the Al-Au interface, and shear strength of Al-Au ultrasonic bonding were investigated by the combining experiments and finite element (FE) simulation. The quantitative model of atomic diffusion, which is related to the ultrasonic bonding parameters, time and distance, is established to calculate the atomic diffusion of the Al-Au interface. The maximum relative error between the calculated and experimental fraction of Al atom is 7.35%, indicating high prediction accuracy of this model. During the process of ultrasonic bonding, Au8Al3 is the main intermetallic compound (IMC) at the Al-Au interface. With larger bonding forces, higher ultrasonic powers and longer bonding time, it is more difficult to remove the oxide particles from the Al-Au interface, which hinders the atomic diffusion. Therefore, the complicated stress state and the existence of oxide particles both promotes the formation of holes. The shear strength of Al-Au ultrasonic bonding increases with increasing bonding force, ultrasonic power and bonding time. However, combined with the presence of holes at especial parameters, the optimal ultrasonic bonding parameter is confirmed to be a bonding force of 23 gf, ultrasonic power of 75 mW and bonding time of 21 ms.展开更多
The remarkable ability of titanium alloys to preserve their superior physical and chemical characteristics when subjected to extreme conditions significantly enhances their importance in the aerospace,military,and med...The remarkable ability of titanium alloys to preserve their superior physical and chemical characteristics when subjected to extreme conditions significantly enhances their importance in the aerospace,military,and medical sectors.However,conventional machining of titanium alloys leads to elevated tool wear,development of surface defects,and reduced machining efficiency due to their low heat conductivity,and chemical affinity.These issues can be somewhat counteracted by integrating ultrasonic vibration in the conventional machining of titanium alloys and also enhance sustainability.This review article offers a holistic evaluation of the influence of ultrasonic vibration-assisted milling and turning on cutting forces,temperature,tool wear,and surface integrity,encompassing surface morphology,surface roughness,surface residual stress,surface hardness,and surface tribological properties during titanium alloys machining.Furthermore,it investigates the sustainability aspect that has not been previously examined.Studies on the performance of ultrasonic-assisted cutting revealed several advantages,including decreased cutting forces and cutting temperature,improved tool life,and a better-machined surface during machining.Consequently,the sustainability factor is improved due to minimized energy consumption and residual waste.In conclusion,the key challenges and future prospects in the ultrasonic-assisted cutting of titanium alloys are also discussed.This review article provides beneficial knowledge for manufactur-ers and researchers regarding ultrasonic vibration-assisted cutting of titanium alloy and will play an important role in achieving sustainability in the industry.展开更多
The composite structures/components made by friction stir lap welding(FSLW)of Mg alloy sheet and Al alloy sheet are of wide application potentials in the manufacturing sector of transportation vehicles.To further impr...The composite structures/components made by friction stir lap welding(FSLW)of Mg alloy sheet and Al alloy sheet are of wide application potentials in the manufacturing sector of transportation vehicles.To further improve the joint quality,the ultrasonic vibration(UV)is exerted in FSLW,and the UV enhanced FSLW(UVeFSLW)was developed for making Mg-to-Al dissimilar joints.The numerical analysis and experimental investigation were combined to study the process mechanism in Mg/Al UVeFSLW.An equation related to the temperature and strain rate was derived to calculate the grain size at different locations of the weld nugget zone,and the effect of grain size distribution on the threshold thermal stress was included,so that the prediction accuracy of flow stress was further improved.With such modified constitutive equation,the numerical simulation was conducted to compare the heat generation,temperature profiles and material flow behaviors in Mg/Al UVeFSLW/FSLW processes.It was found that the exerted UV decreased the temperature at two checking points on the tool/workpiece interface from 707/671 K in FSLW to 689/660 K in UVeFSLW,which suppressed the IMCs thickness at Mg-Al interface from 1.7μm in FSLW to 1.1μm in UVeFSLW.The exerted UV increased the horizontal materials flow ability,and decreased the upward flow ability,which resulted in the increase of effective sheet thickness/effective lap width from 2.01/3.70 mm in FSLW to 2.04/4.84 mm in UVeFSLW.Therefore,the ultrasonic vibration improved the tensile shear strength of Mg-to-Al lap joints by 18%.展开更多
Superior strength and high-temperature performance make γ-TiAl vital for lightweight aero-engines. However, its inherent brittleness poses machining problems. This study employed Elliptical Ultrasonic Vibration Milli...Superior strength and high-temperature performance make γ-TiAl vital for lightweight aero-engines. However, its inherent brittleness poses machining problems. This study employed Elliptical Ultrasonic Vibration Milling (EUVM) to address these problems. Considering the influence of machining parameters on vibration patterns of EUVM, a separation time model was established to analyze the vibration evolutionary process, thereby instructing the cutting mechanism. On this basis, deep discussions regarding chip formation, cutting force, edge breakage, and subsurface layer deformation were conducted for EUVM and Conventional Milling (CM). Chip morphology showed the chip formation was rooted in the periodic brittle fracture. Local dimples proved that the thermal effect of high-speed cutting improved the plasticity of γ-TiAl. EUVM achieved a maximum 18.17% reduction in cutting force compared with CM. The force variation mechanism differed with changes in the cutting speed or the vibration amplitude, and its correlation with thermal softening, strain hardening, and vibratory cutting effects was analyzed. EUVM attained desirable edge breakage by achieving smaller fracture lengths. The fracture mechanisms of different phases were distinct, causing a surge in edge fracture size of γ-TiAl under microstructural differences. In terms of subsurface deformation, EUVM also showed strengthening effects. Noteworthy, the lamellar deformation patterns under the cutting removal state differed from the quasi-static, which was categorized by the orientation angles. Additionally, the electron backscattering diffraction provided details of the influence of microstructural difference on the orientation and the deformation of grains in the subsurface layer. The results demonstrate that EUVM is a promising machining method for γ-TiAl and guide further research and development of EUVM γ-TiAl.展开更多
The loaded rock experiences multiple stages of deformation.It starts with the formation of microcracks at low stresses(crack initiation,CI)and then transitions into unstable crack propagation(crack damage,CD)near the ...The loaded rock experiences multiple stages of deformation.It starts with the formation of microcracks at low stresses(crack initiation,CI)and then transitions into unstable crack propagation(crack damage,CD)near the ultimate strength.In this study,both the acoustic emission method(AEM)and the ultrasonic testing method(UTM)were used to examine the characteristics of AE parameters(b-value,peak frequency,frequency-band energy ratio,and fractal dimension)and ultrasonic(ULT)properties(velocity,amplitude,energy attenuation,and scattering attenuation)of bedded shale at CI,CD,and ultimate strength.The comparison involved analyzing the strain-based method(SBM),AEM,and UTM to determine the thresholds for damage stress.A fuzzy comprehensive evaluation model(FCEM)was created to describe the damage thresholds and hazard assessment.The results indicate that the optimal AE and ULT parameters for identifying CI and CD stress are ringing count,ultrasonic amplitude,energy attenuation,and scattering attenuation of the S-wave.Besides,damage thresholds were detected earlier by AE monitoring,ranging from 3 MPa to 10 MPa.CI and CD identified by UTM occurred later than SBM and AEM,and were in the range of 12 MPa.The b-value,peak frequency,energy ratio in the low-frequency band(0e62.5 kHz),correlation dimension,and sandbox dimension showed low values at the peak stress,while the energy ratio in a moderate-frequency band(187.5e281.25 kHz)and amplitude showed high values.The successful application of FCEM to laboratory testing of shales has demonstrated its ability to quantitatively identify AE/ULT precursors of seismic hazards associated with rock failure.展开更多
The purpose of this study is to analyze the application of ultrasonic non-destructive testing technology in bridge engineering.During the research phase,based on literature collection and reading,as well as the analys...The purpose of this study is to analyze the application of ultrasonic non-destructive testing technology in bridge engineering.During the research phase,based on literature collection and reading,as well as the analysis of bridge inspection materials,the principle of ultrasonic non-destructive testing technology and its adaptability to bridge engineering are elaborated.Subsequently,starting from the preparation work before inspection until damage assessment,the entire process of ultrasonic non-destructive testing is studied,and finally,a technical system of ultrasonic non-destructive testing for bridge engineering that runs through the entire process is formed.It is hoped that this article can provide technical reference value for relevant units in China,and promote the high-quality development of China’s bridge engineering from a macro perspective.展开更多
A low rare-earth containing ZEK100-O magnesium alloy was welded to AA1230-clad high-strength AA2024-T3 aluminum alloy via solidstate ultrasonic spot welding(USW)to evaluate the microstructure,tensile lap shear strengt...A low rare-earth containing ZEK100-O magnesium alloy was welded to AA1230-clad high-strength AA2024-T3 aluminum alloy via solidstate ultrasonic spot welding(USW)to evaluate the microstructure,tensile lap shear strength,and fatigue properties.The tensile strength increased with increasing welding energy,peaked at a welding energy of 1000 J,and then decreased due to the formation of an increasingly thick diffusion layer mainly containing Al12Mg17intermetallic compound at higher energy levels.The peak tensile lap shear strength attained at 1000 J was attributed to the optimal inter-diffusion between the magnesium alloy and softer AA1230-clad Al layer along with the presence of‘fishhook'-like mechanical interlocks at the weld interface and the formation of an indistinguishable intermetallic layer.The dissimilar joints welded at 1000 J also exhibited a longer fatigue life than other Mg-Al dissimilar joints,suggesting the beneficial role of the softer clad layer with a better intermingling capacity during USW.While the transverse-through-thickness(TTT)failure mode prevailed at lower cyclic loading levels,interfacial failure was the predominant mode of fatigue failure at higher cyclic loads,where distinctive fatigue striations were also observed on the fracture surface of the softer clad Al layer.This was associated with the presence of opening stress and bending moment near the nugget edge despite the tension-tension lap shear cyclic loading applied.展开更多
The Mg-9Li-1Zn(LZ91)alloy was subjected to an ultrasonic surface rolling process(USRP)with varying passes for the purpose of modifying its surface state.The USRP transformed surface residual stress from initial tensil...The Mg-9Li-1Zn(LZ91)alloy was subjected to an ultrasonic surface rolling process(USRP)with varying passes for the purpose of modifying its surface state.The USRP transformed surface residual stress from initial tensile stress to compressive stress,decreasing the surface roughness and increasing the ratio of the β-Li phase.The USRPed LZ91 sample(3 passes)showed superior corrosion resistance,with the corrosion current density changing from 57.11 to 24.70μA cm^(-2),and the polarization resistance increasing from 576.3 to 1146.1Ωcm^(2).According to the corrosion procedure evaluations,in situ observation revealed that the LZ91 alloy initially experiences pitting,which subsequently develops into cracking.The substantial area coverage of the β-Li phase facilitates the formation of a protective film on the surface,effectively delaying localized corrosion.展开更多
Conductor materials with good mechanical performance as well as high electrical and thermal conductivities are particularly important to break through the current bottle-neck limit(~ 100 T) of pulsed magnets. Here, we...Conductor materials with good mechanical performance as well as high electrical and thermal conductivities are particularly important to break through the current bottle-neck limit(~ 100 T) of pulsed magnets. Here, we perform systematic studies on the elastic properties of the Cu–6wt% Ag alloy wire, which is a promising candidate material for the new-generation pulsed magnets, by employing two independent ultrasonic techniques, i.e., resonant ultrasound spectroscopy(RUS) and ultrasound pulse-echo experiments. Our RUS measurements manifest that the elastic properties of the Cu–6wt% Ag alloy wires can be improved by an electroplastic drawing procedure as compared with the conventional cold drawing. We also take this opportunity to test the availability of our newly-built ultrasound pulse-echo facility at the Wuhan National High Magnetic Field Center(WHMFC, China), and the results suggest that the elastic performance of the electroplastically-drawn Cu–6wt% Ag alloy wire remains excellent without anomalous softening under extreme conditions,e.g., in ultra-high magnetic field up to 50 T and nitrogen or helium cryogenic liquids.展开更多
BiVO_(4)porous spheres modified by ZnO were designed and synthesized using a facile two-step method.The resulting ZnO/BiVO_(4)composite catalysts have shown remarkable efficiency as piezoelectric catalysts for degradi...BiVO_(4)porous spheres modified by ZnO were designed and synthesized using a facile two-step method.The resulting ZnO/BiVO_(4)composite catalysts have shown remarkable efficiency as piezoelectric catalysts for degrading Rhodamine B(RhB)unde mechanical vibrations,they exhibit superior activity compared to pure ZnO.The 40wt%ZnO/BiVO_(4)heterojunction composite displayed the highest activity,along with good stability and recyclability.The enhanced piezoelectric catalytic activity can be attributed to the form ation of an I-scheme heterojunction structure,which can effectively inhibit the electron-hole recombination.Furthermore,hole(h+)and superoxide radical(·O_(2)^(-))are proved to be the primary active species.Therefore,ZnO/BiVO_(4)stands as an efficient and stable piezoelectric catalyst with broad potential application in the field of environmental water pollution treatment.展开更多
To address the dual challenges of resource utilization of mining solid waste(e.g.,coal gangue)and performance enhancement of cemented rockfill,this study systematically investigates the mechanisms of ultrasonic disper...To address the dual challenges of resource utilization of mining solid waste(e.g.,coal gangue)and performance enhancement of cemented rockfill,this study systematically investigates the mechanisms of ultrasonic dispersion time and polycarboxylate superplasti-cizer(PCE)on the properties of cellulose nanofiber(CNF)-modified cemented rockfill.A series of comparative experiments were de-signed with varying ultrasonic dispersion times(0-60 min)and PCE dosages(0.1wt%-0.4wt%).Through mechanical testing,hydration product analysis,and microstructural characterization,the study revealed the advantages of PCE in promoting CNF dispersion to enhance the engineering applicability of cemented rockfill.The results demonstrate that:(1)Ultrasonic dispersion for 30 min increases the com-pressive strength by 37.7%compared to the untreated group;however,excessive ultrasonication(60 min)induces hydrolysis of CNF,re-leasing reducing sugars that retard hydration.(2)PCE facilitates CNF dispersion,achieving a 29.1%increase in compressive strength at a dosage of 0.4wt%,while simultaneously improving hydration products and microstructural development.(3)While ultrasonic dispersion yields slightly higher strength improvements,PCE demonstrates superior cost-effectiveness and operational convenience,rendering it more viable for industrial adoption.This study provides a theoretical foundation for the nano-enhanced modification of cemented rockfill,offering new insights into the recycling of solid waste and the development of high-performance materials.展开更多
Concrete is one of the most important elements in building construction.However,concrete used in construction is susceptible to damage due to corrosion.The influence of corrosive substances causes changes in the reinf...Concrete is one of the most important elements in building construction.However,concrete used in construction is susceptible to damage due to corrosion.The influence of corrosive substances causes changes in the reinforcing steel and affects the strength of the structure.The repair method is one approach to overcome this problem.This research aims to determine the effect of grouting and jacketing repairs on corroded concrete.The concrete used has dimensions of 15 cm×15 cm×60 cm with planned corrosion variations of 50%,60%,and 70%.The test objects were tested using the Non-Destructive Testing(NDT)method using Ultrasonic Pulse Velocity(UPV).The test results show that the average speed of normal concrete is 5070 m/s,while the lowest average speed is 3070 m/s on the 70%planned corrosion test object.The test object was then given a load of 1600 kgf.At this stage,there is a decrease in speed and wave shape with the lowest average speed obtained at 2753 m/s.The repair method is an effort to restore concrete performance by using grouting and jacketing.Grouting is done by injecting mortar material into it.Jacketing involves adding thickness to the existing concrete layer with additional layers of concrete.After improvements were made,there was an improvement in the UPV test,with a peak speed value of 4910 m/s.Repairing concrete by filling cracks can improve concrete continuity and reduce waveform distortion,thereby increasing wave propagation speed.展开更多
To advance materials with superior performance,the construction of gradient structures has emerged as a promising strategy.In this study,a gradient nanocrystalline-amorphous structure was induced in Zr46Cu46Al8 bulk m...To advance materials with superior performance,the construction of gradient structures has emerged as a promising strategy.In this study,a gradient nanocrystalline-amorphous structure was induced in Zr46Cu46Al8 bulk metallic glass(BMG)through ultrasonic vibration(UV)treatment.Applying a 20 kHz ultrasonic cyclic loading in the elastic regime,controllable gradient structures with varying crystallized volume fractions can be achieved in less than 2 s by adjusting the input UV energy.In contrast to tradi-tional methods of inducing structural gradients in BMGs,this novel approach offers distinct advantages:it is exceptionally rapid,requires minimal stress,and allows for easy tuning of the extent of structural gradients through precise adjustment of processing parameters.Nanoindentation tests reveal higher hard-ness near the struck surface,attributed to a greater degree of nanocrystal formation,which gradually di-minishes with depth.As a result of the gradient dispersion of nanocrystals,an increased plasticity was found after UV treatment,characterized by the formation of multiple shear bands.Microstructural in-vestigations suggest that UV-induced nanocrystallization originates from local atomic rearrangements in phase-separated Cu-rich regions with high diffusional mobility.Our study underscores the tunability of structural gradients and corresponding performance improvements in BMGs through ultrasonic energy modulation,offering valuable insights for designing advanced metallic materials with tailored mechanical properties.展开更多
In this paper,the stability of the results of ultrasonic wood surface modification after long-term storage,including macroscopic properties and microstructure of specimens,was investigated.Specimens of aspen wood(Popu...In this paper,the stability of the results of ultrasonic wood surface modification after long-term storage,including macroscopic properties and microstructure of specimens,was investigated.Specimens of aspen wood(Populus tremula)were processed by the developed ultrasonic method of wood surface modification in three different treatment modes and the surface hardness of the specimens was evaluated after processing and after storing the specimens for more than 5 years since long-term stability is an important factor for the use of ultrasonically modified sawn timber as construction and finishing materials.The obtained results of surface hardness measurements by the Leeb method showed that the decrease in hardness after long-term storage is approximately 6.6%for the lowest degree of treatment and approximately 3.4%and 2.4%for medium and high degrees of treatment,taking into account the fact of the average increase in surface hardness approximately 2–4 times,this decrease is insignificant.The internal structure of the specimens after storage was studied by scanning electron microscope(SEM),and deformations of the wood surface layer without damage or rupture were analyzed.The derived stable results confirm the potential of the ultrasonic method for wood surface modification.展开更多
Dear Editor,Chemotherapy remains ineffective against solid tumors due to their dense extracellular matrix, abnormal vasculature, and high interstitial pressure coalesce to create a barrier to drug penetration and dist...Dear Editor,Chemotherapy remains ineffective against solid tumors due to their dense extracellular matrix, abnormal vasculature, and high interstitial pressure coalesce to create a barrier to drug penetration and distribution. This challenge is even particularly pronounced in pancreatic and brain tumors, where chemotherapy response rates remain dismal.The advent of ultrasonic tumor permeabilization using focused ultrasound and microbubble technology represents a significant breakthrough in research on overcoming drug resistance in solid tumors toward overcoming these barriers and improving outcomes.[1]展开更多
Polymer microfluidic chips are a common tool in biomedical research,and the production of mold inserts with microscale structures represents a crucial step in the precise molding of these chips.Electrical discharge ma...Polymer microfluidic chips are a common tool in biomedical research,and the production of mold inserts with microscale structures represents a crucial step in the precise molding of these chips.Electrical discharge machining(EDM)can achieve high-quality machining of microstructures on high-hardness mold steel inserts.This can reduce the manufacturing cost of microfluidic chip molds and extend the service life of molds.However,the EDM process is susceptible to the formation of poor-quality surfaces due to the occurrence of abnormal discharges.To address this issue,this paper presents in-depth research on a novel ultrasonic cavitation-assisted electrical discharge machining method.An ultrasonic transducer is placed in an electrical discharge working fluid to promote the removal of electrical corrosion products through the cavitation effect of the liquid.This can also reduce the occurrence of poor discharge,thereby improving the machining surface quality.The aluminum foil corrosion method is employed to investigate the distribution of ultrasonic action in the electric discharge working fluid.The attenuation law of ultrasonic action in the electric discharge working fluid is also investigated.The range of ultrasonic action is determined,providing a reference for subsequent ultrasonic vibration electric discharge working fluid processing experiments.The results of the aluminum foil tests are used to inform the selection of NAK80 mold steel as the experimental object.The effects of cavitation at three ultrasonic frequencies on the surface microstructure are investigated.The experimental results indicate that ultrasonic cavitation can facilitate the movement of corrosion products in electrical machining,reduce the occurrence of abnormal discharges caused by carbon deposition or the secondary re-melting of metals,and thereby enhance the machining surface quality.展开更多
BACKGROUND Esophageal cancer is a prevalent solid malignancy of the gastrointestinal tract.Surgical resection remains an effective intervention for prolonging patient survival.While conventional open surgery demonstra...BACKGROUND Esophageal cancer is a prevalent solid malignancy of the gastrointestinal tract.Surgical resection remains an effective intervention for prolonging patient survival.While conventional open surgery demonstrates therapeutic efficacy,it is often associated with significant tissue trauma,high complication rates,and prolonged recovery period.Advances in imaging technology and refined minimally invasive techniques have led to an increasing adoption of total thoracoscopy-assisted resection among patients.However,the efficacy of total thoracoscopic ultrasonic scalpel resection specifically for esophageal cancer patients remains unclear.AIM To evaluate the efficacy of total thoracoscopic ultrasonic scalpel resection in esophageal cancer patients.METHODS We retrospectively analyzed clinical data from 127 esophageal cancer patients undergoing total thoracoscopy-assisted resection in our hospital from January 2022 to January 2025.Based on surgical technique,61 patients subjected to total thoracoscopic electrosurgical scalpel esophagectomy were included in the control group,while 66 patients receiving total thoracoscopic ultrasonic scalpel esophagectomy were assigned to the observation group.Perioperative outcomes were compared between the two groups,including pain mediators[5-hydroxytryptamine(5-HT),potassium ions(K^(+)),norepinephrine(NE)],immune indices(CD4^(+),CD8^(+),CD4^(+)/CD8^(+)),inflammatory markers[interleukin-6(IL-6),interleukin-8(IL-8),tumor necrosis factor alpha(TNF-α)],as well as pulmonary function parameters[forced vital capacity(FVC),forced expiratory volume in one second(FEV1),maximal voluntary ventilation(MVV)].Besides,complication rates were also assessed.RESULTS Operative time was significantly shorter in the observation group compared to the control group.The observation group demonstrated reduced intraoperative blood loss and lower postoperative chest drainage volume and increased number of dissected lymph nodes(P<0.05 for all).Preoperatively,no significant differences were observed between the two groups in terms of 5-HT,K^(+),NE,CD4^(+),CD8^(+),CD4^(+)/CD8^(+),IL-6,IL-8,TNF-α,FVC,FEV1,and MVV(P>0.05).Postoperatively,both groups showed improvement in measured parameters,with the observation group exhibiting significantly better outcomes,that is,lower 5-HT,K^(+),and NE levels,higher CD4^(+)levels,lower CD8^(+)levels,and higher CD4^(+)/CD8^(+)levels(P<0.05);reduced IL-6,IL-8,and TNF-α(P<0.05);superior FVC,FEV1,and MVV measurements(P<0.05).The total complication rate was significantly lower in the observation group(7.58%vs 21.31%;P<0.05).CONCLUSION Total thoracoscopic ultrasonic scalpel resection demonstrates superior surgical outcomes in esophageal cancer patients compared to electrosurgical techniques.This approach significantly improves perioperative indicators,ameliorates postoperative pain,enhances immune function,alleviates inflammatory responses,and preserves pulmonary function,demonstrating the safety and reliability of this technique in esophageal cancer patients.展开更多
基金supported by the Major Science and Technology Project of Zhongshan City(No.2022AJ004)the Key Basic and Applied Research Program of Guangdong Province(Nos.2019B030302010 and 2022B1515120082)Guangdong Science and Technology Innovation Project(No.2021TX06C111).
文摘In general,the rapid growth of α-Fe clusters is a challenge in high Fe-content Fe-based amorphous alloys,negatively affecting their physical properties.Herein,we introduce an efficient and rapid post-treatment technique known as ultrasonic vibration rapid processing(UVRP),which enables the formation of high-density strong magnetic α-Fe clusters,thereby enhancing the soft magnetic properties of Fe_(78)Si(13)B_(9) amorphous alloy ribbon.
基金supported by Key Projects of Science and Technology Research Plan of Hubei Provincial Department of Education(D20221306)the National Natural Science Foundation of China(51605103)Key Project of Hubei Provincial Science and Technology Department(2020BAB055).
文摘As light metals,aluminum and magnesium have been widely used in automotive manufacturing,but the welding of Al/Mg joints is facing challenges.However,it is difficult to obtain high-quality aluminum/magnesium joints with traditional arc welding methods.As a solid-phase welding technology,ultrasonic metal welding has the characteristics of high welding efficiency and less welded defects.It is also suitable for welding sound metal bonds.Aluminum and magnesium ultrasonic welding has become a research hotspot.Therefore,the evolution of microstructures and mechanical performance of Al/Mg and multi-layer Al/Mg ultrasonic welding,and the new study works,including the molecular dynamic simulation of Al/Mg ultrasonic welding and hybrid based on ultrasonic welding are summarized.Furthermore,several promising research directions are proposed to guide in-depth investigations into the ultrasonic welding of Al/Mg dissimilar joints.
基金supported by the National Natural Science Foundation of China(Nos.91960203 and 52375399)the Chinese Aeronautical Establishment Aeronautical Science Foundation(No.2022Z045051001).
文摘Ultrasonic elliptical vibration cutting(UEVC)with clockwise elliptical vibration has made notable achievements in precision machining;however,its critical cutting speed limits its application to low-speed machining tasks.Meanwhile,rotary ultrasonic elliptical machining(RUEM)with clockwise elliptical vibration has been validated as an effective high-speed cutting technology.Unfortunately,conventional RUEM leads to increased surface roughness.To address this issue and enhance machining quality,we propose a novel RUEM method employing an anticlockwise vibration direction,called anticlockwise rotary ultrasonic elliptical machining(ARUEM).The mechanisms of surface formation and subsurface strengthening for ARUEM are analyzed.Experimental validations were performed on Ti-6Al-4V alloy,revealing that ARUEM achieved substantially lower ridge heights and up to a 50%reduction in surface roughness compared to conventional RUEM.Additionally,relative to conventional milling,ARUEM resulted in up to 122.6%thicker plastic deformation layers,53.4%higher surface residual compressive stress,and 19.3%greater surface micro-hardness.This study showcases a promising method for high-performance milling of Ti-6Al-4V,offers new insights into RUEM by examining the influence of vibration direction,and enhances understanding of surface formation and subsurface strengthening in the ARUEM method.
基金Project(2022YFB3707201) supported by the National Key R&D Program of ChinaProject(U2341254) supported by the Ye Qisun Science Foundation of National Natural Science Foundation of China+1 种基金Projects(0604022GH0202143,0604022SH0201143) supported by the NPU Aoxiang Distinguished Young Scholars,ChinaProject supported by the Funding of Young Top-notch Talent of the National Ten Thousand Talent Program,China。
文摘Effects of ultrasonic bonding parameters on atomic diffusion, microstructure at the Al-Au interface, and shear strength of Al-Au ultrasonic bonding were investigated by the combining experiments and finite element (FE) simulation. The quantitative model of atomic diffusion, which is related to the ultrasonic bonding parameters, time and distance, is established to calculate the atomic diffusion of the Al-Au interface. The maximum relative error between the calculated and experimental fraction of Al atom is 7.35%, indicating high prediction accuracy of this model. During the process of ultrasonic bonding, Au8Al3 is the main intermetallic compound (IMC) at the Al-Au interface. With larger bonding forces, higher ultrasonic powers and longer bonding time, it is more difficult to remove the oxide particles from the Al-Au interface, which hinders the atomic diffusion. Therefore, the complicated stress state and the existence of oxide particles both promotes the formation of holes. The shear strength of Al-Au ultrasonic bonding increases with increasing bonding force, ultrasonic power and bonding time. However, combined with the presence of holes at especial parameters, the optimal ultrasonic bonding parameter is confirmed to be a bonding force of 23 gf, ultrasonic power of 75 mW and bonding time of 21 ms.
基金financially supported by the National Natural Science Foundation of China(Nos.92160301,92060203,52175415 and 52205475)the Science Center for Gas Turbine Project(No.P2023-B-IV-003-001)+1 种基金the Natural Science Foundation of Jiangsu Province(No.BK20210295)the Huaqiao University Engineering Research Center of Brittle Materials Machining(MOE,2023IME-001)。
文摘The remarkable ability of titanium alloys to preserve their superior physical and chemical characteristics when subjected to extreme conditions significantly enhances their importance in the aerospace,military,and medical sectors.However,conventional machining of titanium alloys leads to elevated tool wear,development of surface defects,and reduced machining efficiency due to their low heat conductivity,and chemical affinity.These issues can be somewhat counteracted by integrating ultrasonic vibration in the conventional machining of titanium alloys and also enhance sustainability.This review article offers a holistic evaluation of the influence of ultrasonic vibration-assisted milling and turning on cutting forces,temperature,tool wear,and surface integrity,encompassing surface morphology,surface roughness,surface residual stress,surface hardness,and surface tribological properties during titanium alloys machining.Furthermore,it investigates the sustainability aspect that has not been previously examined.Studies on the performance of ultrasonic-assisted cutting revealed several advantages,including decreased cutting forces and cutting temperature,improved tool life,and a better-machined surface during machining.Consequently,the sustainability factor is improved due to minimized energy consumption and residual waste.In conclusion,the key challenges and future prospects in the ultrasonic-assisted cutting of titanium alloys are also discussed.This review article provides beneficial knowledge for manufactur-ers and researchers regarding ultrasonic vibration-assisted cutting of titanium alloy and will play an important role in achieving sustainability in the industry.
基金supported by the National Natural Science Foundation of China(Grant No.52035005)the Key R&D Program of Shandong Province in China(Grant No.2021ZLGX01).
文摘The composite structures/components made by friction stir lap welding(FSLW)of Mg alloy sheet and Al alloy sheet are of wide application potentials in the manufacturing sector of transportation vehicles.To further improve the joint quality,the ultrasonic vibration(UV)is exerted in FSLW,and the UV enhanced FSLW(UVeFSLW)was developed for making Mg-to-Al dissimilar joints.The numerical analysis and experimental investigation were combined to study the process mechanism in Mg/Al UVeFSLW.An equation related to the temperature and strain rate was derived to calculate the grain size at different locations of the weld nugget zone,and the effect of grain size distribution on the threshold thermal stress was included,so that the prediction accuracy of flow stress was further improved.With such modified constitutive equation,the numerical simulation was conducted to compare the heat generation,temperature profiles and material flow behaviors in Mg/Al UVeFSLW/FSLW processes.It was found that the exerted UV decreased the temperature at two checking points on the tool/workpiece interface from 707/671 K in FSLW to 689/660 K in UVeFSLW,which suppressed the IMCs thickness at Mg-Al interface from 1.7μm in FSLW to 1.1μm in UVeFSLW.The exerted UV increased the horizontal materials flow ability,and decreased the upward flow ability,which resulted in the increase of effective sheet thickness/effective lap width from 2.01/3.70 mm in FSLW to 2.04/4.84 mm in UVeFSLW.Therefore,the ultrasonic vibration improved the tensile shear strength of Mg-to-Al lap joints by 18%.
基金co-supported by the Science Center for Gas Turbine Project, China(No. P2022-AB-IV-001-002)the National Natural Science Foundation of China (No. 91960203)+1 种基金the Fundamental Research Funds for the Central Universities (No. D5000230048)the Innovation Capability Support Program of Shaanxi (No. 2022TD-60)
文摘Superior strength and high-temperature performance make γ-TiAl vital for lightweight aero-engines. However, its inherent brittleness poses machining problems. This study employed Elliptical Ultrasonic Vibration Milling (EUVM) to address these problems. Considering the influence of machining parameters on vibration patterns of EUVM, a separation time model was established to analyze the vibration evolutionary process, thereby instructing the cutting mechanism. On this basis, deep discussions regarding chip formation, cutting force, edge breakage, and subsurface layer deformation were conducted for EUVM and Conventional Milling (CM). Chip morphology showed the chip formation was rooted in the periodic brittle fracture. Local dimples proved that the thermal effect of high-speed cutting improved the plasticity of γ-TiAl. EUVM achieved a maximum 18.17% reduction in cutting force compared with CM. The force variation mechanism differed with changes in the cutting speed or the vibration amplitude, and its correlation with thermal softening, strain hardening, and vibratory cutting effects was analyzed. EUVM attained desirable edge breakage by achieving smaller fracture lengths. The fracture mechanisms of different phases were distinct, causing a surge in edge fracture size of γ-TiAl under microstructural differences. In terms of subsurface deformation, EUVM also showed strengthening effects. Noteworthy, the lamellar deformation patterns under the cutting removal state differed from the quasi-static, which was categorized by the orientation angles. Additionally, the electron backscattering diffraction provided details of the influence of microstructural difference on the orientation and the deformation of grains in the subsurface layer. The results demonstrate that EUVM is a promising machining method for γ-TiAl and guide further research and development of EUVM γ-TiAl.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.U20A20266 and 12302503)Scientific and technological research projects in Sichuan province(Grant No.2024NSFSC0973).
文摘The loaded rock experiences multiple stages of deformation.It starts with the formation of microcracks at low stresses(crack initiation,CI)and then transitions into unstable crack propagation(crack damage,CD)near the ultimate strength.In this study,both the acoustic emission method(AEM)and the ultrasonic testing method(UTM)were used to examine the characteristics of AE parameters(b-value,peak frequency,frequency-band energy ratio,and fractal dimension)and ultrasonic(ULT)properties(velocity,amplitude,energy attenuation,and scattering attenuation)of bedded shale at CI,CD,and ultimate strength.The comparison involved analyzing the strain-based method(SBM),AEM,and UTM to determine the thresholds for damage stress.A fuzzy comprehensive evaluation model(FCEM)was created to describe the damage thresholds and hazard assessment.The results indicate that the optimal AE and ULT parameters for identifying CI and CD stress are ringing count,ultrasonic amplitude,energy attenuation,and scattering attenuation of the S-wave.Besides,damage thresholds were detected earlier by AE monitoring,ranging from 3 MPa to 10 MPa.CI and CD identified by UTM occurred later than SBM and AEM,and were in the range of 12 MPa.The b-value,peak frequency,energy ratio in the low-frequency band(0e62.5 kHz),correlation dimension,and sandbox dimension showed low values at the peak stress,while the energy ratio in a moderate-frequency band(187.5e281.25 kHz)and amplitude showed high values.The successful application of FCEM to laboratory testing of shales has demonstrated its ability to quantitatively identify AE/ULT precursors of seismic hazards associated with rock failure.
文摘The purpose of this study is to analyze the application of ultrasonic non-destructive testing technology in bridge engineering.During the research phase,based on literature collection and reading,as well as the analysis of bridge inspection materials,the principle of ultrasonic non-destructive testing technology and its adaptability to bridge engineering are elaborated.Subsequently,starting from the preparation work before inspection until damage assessment,the entire process of ultrasonic non-destructive testing is studied,and finally,a technical system of ultrasonic non-destructive testing for bridge engineering that runs through the entire process is formed.It is hoped that this article can provide technical reference value for relevant units in China,and promote the high-quality development of China’s bridge engineering from a macro perspective.
基金the National Natural Science Foundation of China(Grant No.51971183)supported by OU(Osaka University,Japan)program for multilateral international collaboration research in joining and welding。
文摘A low rare-earth containing ZEK100-O magnesium alloy was welded to AA1230-clad high-strength AA2024-T3 aluminum alloy via solidstate ultrasonic spot welding(USW)to evaluate the microstructure,tensile lap shear strength,and fatigue properties.The tensile strength increased with increasing welding energy,peaked at a welding energy of 1000 J,and then decreased due to the formation of an increasingly thick diffusion layer mainly containing Al12Mg17intermetallic compound at higher energy levels.The peak tensile lap shear strength attained at 1000 J was attributed to the optimal inter-diffusion between the magnesium alloy and softer AA1230-clad Al layer along with the presence of‘fishhook'-like mechanical interlocks at the weld interface and the formation of an indistinguishable intermetallic layer.The dissimilar joints welded at 1000 J also exhibited a longer fatigue life than other Mg-Al dissimilar joints,suggesting the beneficial role of the softer clad layer with a better intermingling capacity during USW.While the transverse-through-thickness(TTT)failure mode prevailed at lower cyclic loading levels,interfacial failure was the predominant mode of fatigue failure at higher cyclic loads,where distinctive fatigue striations were also observed on the fracture surface of the softer clad Al layer.This was associated with the presence of opening stress and bending moment near the nugget edge despite the tension-tension lap shear cyclic loading applied.
基金financially supported by the National Natural Science Foundation of China(No.52271091)the National Key Research and Development Program of China(No.2021YFB3701100)the Natural Science Foundation Project of Ningxia Province(No.2023AAC03324).
文摘The Mg-9Li-1Zn(LZ91)alloy was subjected to an ultrasonic surface rolling process(USRP)with varying passes for the purpose of modifying its surface state.The USRP transformed surface residual stress from initial tensile stress to compressive stress,decreasing the surface roughness and increasing the ratio of the β-Li phase.The USRPed LZ91 sample(3 passes)showed superior corrosion resistance,with the corrosion current density changing from 57.11 to 24.70μA cm^(-2),and the polarization resistance increasing from 576.3 to 1146.1Ωcm^(2).According to the corrosion procedure evaluations,in situ observation revealed that the LZ91 alloy initially experiences pitting,which subsequently develops into cracking.The substantial area coverage of the β-Li phase facilitates the formation of a protective film on the surface,effectively delaying localized corrosion.
基金Project supported by the National Key R&D Program of China (Grant Nos. 2022YFA1602602 and 2023YFA1609600)the National Natural Science Foundation of China (Grant No. U23A20580)+3 种基金the open research fund of Songshan Lake Materials Laboratory (Grant No. 2022SLABFN27)Beijing National Laboratory for Condensed Matter Physics (Grant No. 2024BNLCMPKF004)Guangdong Basic and Applied Basic Research Foundation (Grant No. 2022B1515120020)the interdisciplinary program of Wuhan National High Magnetic Field Center at Huazhong University of Science and Technology (Grant No. WHMFC202132)。
文摘Conductor materials with good mechanical performance as well as high electrical and thermal conductivities are particularly important to break through the current bottle-neck limit(~ 100 T) of pulsed magnets. Here, we perform systematic studies on the elastic properties of the Cu–6wt% Ag alloy wire, which is a promising candidate material for the new-generation pulsed magnets, by employing two independent ultrasonic techniques, i.e., resonant ultrasound spectroscopy(RUS) and ultrasound pulse-echo experiments. Our RUS measurements manifest that the elastic properties of the Cu–6wt% Ag alloy wires can be improved by an electroplastic drawing procedure as compared with the conventional cold drawing. We also take this opportunity to test the availability of our newly-built ultrasound pulse-echo facility at the Wuhan National High Magnetic Field Center(WHMFC, China), and the results suggest that the elastic performance of the electroplastically-drawn Cu–6wt% Ag alloy wire remains excellent without anomalous softening under extreme conditions,e.g., in ultra-high magnetic field up to 50 T and nitrogen or helium cryogenic liquids.
基金financially supported by the National Natural Science Foundation of China(No.22272151)Public Welfare Technology Application Research Project of Jinhua City,China(No.2023-4-022)。
文摘BiVO_(4)porous spheres modified by ZnO were designed and synthesized using a facile two-step method.The resulting ZnO/BiVO_(4)composite catalysts have shown remarkable efficiency as piezoelectric catalysts for degrading Rhodamine B(RhB)unde mechanical vibrations,they exhibit superior activity compared to pure ZnO.The 40wt%ZnO/BiVO_(4)heterojunction composite displayed the highest activity,along with good stability and recyclability.The enhanced piezoelectric catalytic activity can be attributed to the form ation of an I-scheme heterojunction structure,which can effectively inhibit the electron-hole recombination.Furthermore,hole(h+)and superoxide radical(·O_(2)^(-))are proved to be the primary active species.Therefore,ZnO/BiVO_(4)stands as an efficient and stable piezoelectric catalyst with broad potential application in the field of environmental water pollution treatment.
基金support from the National Natural Science Foundation of China(Nos.42372328,U23B2091,52478253,and 52374147)Natural Science Foundation of Jiangsu Province,China(No.BK20240209).
文摘To address the dual challenges of resource utilization of mining solid waste(e.g.,coal gangue)and performance enhancement of cemented rockfill,this study systematically investigates the mechanisms of ultrasonic dispersion time and polycarboxylate superplasti-cizer(PCE)on the properties of cellulose nanofiber(CNF)-modified cemented rockfill.A series of comparative experiments were de-signed with varying ultrasonic dispersion times(0-60 min)and PCE dosages(0.1wt%-0.4wt%).Through mechanical testing,hydration product analysis,and microstructural characterization,the study revealed the advantages of PCE in promoting CNF dispersion to enhance the engineering applicability of cemented rockfill.The results demonstrate that:(1)Ultrasonic dispersion for 30 min increases the com-pressive strength by 37.7%compared to the untreated group;however,excessive ultrasonication(60 min)induces hydrolysis of CNF,re-leasing reducing sugars that retard hydration.(2)PCE facilitates CNF dispersion,achieving a 29.1%increase in compressive strength at a dosage of 0.4wt%,while simultaneously improving hydration products and microstructural development.(3)While ultrasonic dispersion yields slightly higher strength improvements,PCE demonstrates superior cost-effectiveness and operational convenience,rendering it more viable for industrial adoption.This study provides a theoretical foundation for the nano-enhanced modification of cemented rockfill,offering new insights into the recycling of solid waste and the development of high-performance materials.
基金supported by the Ministry of Education,Culture,Research,and Technology(Indonesia),Grant number 107/E5/PG.02.00.PL/2024,AZ.
文摘Concrete is one of the most important elements in building construction.However,concrete used in construction is susceptible to damage due to corrosion.The influence of corrosive substances causes changes in the reinforcing steel and affects the strength of the structure.The repair method is one approach to overcome this problem.This research aims to determine the effect of grouting and jacketing repairs on corroded concrete.The concrete used has dimensions of 15 cm×15 cm×60 cm with planned corrosion variations of 50%,60%,and 70%.The test objects were tested using the Non-Destructive Testing(NDT)method using Ultrasonic Pulse Velocity(UPV).The test results show that the average speed of normal concrete is 5070 m/s,while the lowest average speed is 3070 m/s on the 70%planned corrosion test object.The test object was then given a load of 1600 kgf.At this stage,there is a decrease in speed and wave shape with the lowest average speed obtained at 2753 m/s.The repair method is an effort to restore concrete performance by using grouting and jacketing.Grouting is done by injecting mortar material into it.Jacketing involves adding thickness to the existing concrete layer with additional layers of concrete.After improvements were made,there was an improvement in the UPV test,with a peak speed value of 4910 m/s.Repairing concrete by filling cracks can improve concrete continuity and reduce waveform distortion,thereby increasing wave propagation speed.
基金supported by the Key Basic and Applied Research Program of Guangdong Province,China(Grant No.2019B030302010)the NSF of China(Grant Nos.52122105,52271150,52201185,52201186,52371160)+1 种基金the Science and Technology Innovation Commission Shenzhen(Grants Nos.RCJC20221008092730037,20220804091920001)the Research Team Cultivation Program of Shenzhen University,Grant No.2023QNT001.
文摘To advance materials with superior performance,the construction of gradient structures has emerged as a promising strategy.In this study,a gradient nanocrystalline-amorphous structure was induced in Zr46Cu46Al8 bulk metallic glass(BMG)through ultrasonic vibration(UV)treatment.Applying a 20 kHz ultrasonic cyclic loading in the elastic regime,controllable gradient structures with varying crystallized volume fractions can be achieved in less than 2 s by adjusting the input UV energy.In contrast to tradi-tional methods of inducing structural gradients in BMGs,this novel approach offers distinct advantages:it is exceptionally rapid,requires minimal stress,and allows for easy tuning of the extent of structural gradients through precise adjustment of processing parameters.Nanoindentation tests reveal higher hard-ness near the struck surface,attributed to a greater degree of nanocrystal formation,which gradually di-minishes with depth.As a result of the gradient dispersion of nanocrystals,an increased plasticity was found after UV treatment,characterized by the formation of multiple shear bands.Microstructural in-vestigations suggest that UV-induced nanocrystallization originates from local atomic rearrangements in phase-separated Cu-rich regions with high diffusional mobility.Our study underscores the tunability of structural gradients and corresponding performance improvements in BMGs through ultrasonic energy modulation,offering valuable insights for designing advanced metallic materials with tailored mechanical properties.
文摘In this paper,the stability of the results of ultrasonic wood surface modification after long-term storage,including macroscopic properties and microstructure of specimens,was investigated.Specimens of aspen wood(Populus tremula)were processed by the developed ultrasonic method of wood surface modification in three different treatment modes and the surface hardness of the specimens was evaluated after processing and after storing the specimens for more than 5 years since long-term stability is an important factor for the use of ultrasonically modified sawn timber as construction and finishing materials.The obtained results of surface hardness measurements by the Leeb method showed that the decrease in hardness after long-term storage is approximately 6.6%for the lowest degree of treatment and approximately 3.4%and 2.4%for medium and high degrees of treatment,taking into account the fact of the average increase in surface hardness approximately 2–4 times,this decrease is insignificant.The internal structure of the specimens after storage was studied by scanning electron microscope(SEM),and deformations of the wood surface layer without damage or rupture were analyzed.The derived stable results confirm the potential of the ultrasonic method for wood surface modification.
文摘Dear Editor,Chemotherapy remains ineffective against solid tumors due to their dense extracellular matrix, abnormal vasculature, and high interstitial pressure coalesce to create a barrier to drug penetration and distribution. This challenge is even particularly pronounced in pancreatic and brain tumors, where chemotherapy response rates remain dismal.The advent of ultrasonic tumor permeabilization using focused ultrasound and microbubble technology represents a significant breakthrough in research on overcoming drug resistance in solid tumors toward overcoming these barriers and improving outcomes.[1]
基金supported by the Higher Education Science and Technology Innovation Project of Shanxi Province(No.2022L706)Natural Science Foundation of Jiangsu Province(No.BK20210755).
文摘Polymer microfluidic chips are a common tool in biomedical research,and the production of mold inserts with microscale structures represents a crucial step in the precise molding of these chips.Electrical discharge machining(EDM)can achieve high-quality machining of microstructures on high-hardness mold steel inserts.This can reduce the manufacturing cost of microfluidic chip molds and extend the service life of molds.However,the EDM process is susceptible to the formation of poor-quality surfaces due to the occurrence of abnormal discharges.To address this issue,this paper presents in-depth research on a novel ultrasonic cavitation-assisted electrical discharge machining method.An ultrasonic transducer is placed in an electrical discharge working fluid to promote the removal of electrical corrosion products through the cavitation effect of the liquid.This can also reduce the occurrence of poor discharge,thereby improving the machining surface quality.The aluminum foil corrosion method is employed to investigate the distribution of ultrasonic action in the electric discharge working fluid.The attenuation law of ultrasonic action in the electric discharge working fluid is also investigated.The range of ultrasonic action is determined,providing a reference for subsequent ultrasonic vibration electric discharge working fluid processing experiments.The results of the aluminum foil tests are used to inform the selection of NAK80 mold steel as the experimental object.The effects of cavitation at three ultrasonic frequencies on the surface microstructure are investigated.The experimental results indicate that ultrasonic cavitation can facilitate the movement of corrosion products in electrical machining,reduce the occurrence of abnormal discharges caused by carbon deposition or the secondary re-melting of metals,and thereby enhance the machining surface quality.
文摘BACKGROUND Esophageal cancer is a prevalent solid malignancy of the gastrointestinal tract.Surgical resection remains an effective intervention for prolonging patient survival.While conventional open surgery demonstrates therapeutic efficacy,it is often associated with significant tissue trauma,high complication rates,and prolonged recovery period.Advances in imaging technology and refined minimally invasive techniques have led to an increasing adoption of total thoracoscopy-assisted resection among patients.However,the efficacy of total thoracoscopic ultrasonic scalpel resection specifically for esophageal cancer patients remains unclear.AIM To evaluate the efficacy of total thoracoscopic ultrasonic scalpel resection in esophageal cancer patients.METHODS We retrospectively analyzed clinical data from 127 esophageal cancer patients undergoing total thoracoscopy-assisted resection in our hospital from January 2022 to January 2025.Based on surgical technique,61 patients subjected to total thoracoscopic electrosurgical scalpel esophagectomy were included in the control group,while 66 patients receiving total thoracoscopic ultrasonic scalpel esophagectomy were assigned to the observation group.Perioperative outcomes were compared between the two groups,including pain mediators[5-hydroxytryptamine(5-HT),potassium ions(K^(+)),norepinephrine(NE)],immune indices(CD4^(+),CD8^(+),CD4^(+)/CD8^(+)),inflammatory markers[interleukin-6(IL-6),interleukin-8(IL-8),tumor necrosis factor alpha(TNF-α)],as well as pulmonary function parameters[forced vital capacity(FVC),forced expiratory volume in one second(FEV1),maximal voluntary ventilation(MVV)].Besides,complication rates were also assessed.RESULTS Operative time was significantly shorter in the observation group compared to the control group.The observation group demonstrated reduced intraoperative blood loss and lower postoperative chest drainage volume and increased number of dissected lymph nodes(P<0.05 for all).Preoperatively,no significant differences were observed between the two groups in terms of 5-HT,K^(+),NE,CD4^(+),CD8^(+),CD4^(+)/CD8^(+),IL-6,IL-8,TNF-α,FVC,FEV1,and MVV(P>0.05).Postoperatively,both groups showed improvement in measured parameters,with the observation group exhibiting significantly better outcomes,that is,lower 5-HT,K^(+),and NE levels,higher CD4^(+)levels,lower CD8^(+)levels,and higher CD4^(+)/CD8^(+)levels(P<0.05);reduced IL-6,IL-8,and TNF-α(P<0.05);superior FVC,FEV1,and MVV measurements(P<0.05).The total complication rate was significantly lower in the observation group(7.58%vs 21.31%;P<0.05).CONCLUSION Total thoracoscopic ultrasonic scalpel resection demonstrates superior surgical outcomes in esophageal cancer patients compared to electrosurgical techniques.This approach significantly improves perioperative indicators,ameliorates postoperative pain,enhances immune function,alleviates inflammatory responses,and preserves pulmonary function,demonstrating the safety and reliability of this technique in esophageal cancer patients.
