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A Novel On-Site-Real-Time Method for Identifying Characteristic Parameters Using Ultrasonic Echo Groups and Neural Network
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作者 Shuyong Duan Jialin Zhang +2 位作者 Heng Ouyang Xu Han Guirong Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第1期215-228,共14页
On-site and real-time non-destructive measurement of elastic constants for materials of a component in a in-service structure is a challenge due to structural complexities,such as ambiguous boundary,variable thickness... On-site and real-time non-destructive measurement of elastic constants for materials of a component in a in-service structure is a challenge due to structural complexities,such as ambiguous boundary,variable thickness,nonuniform material properties.This work develops for the first time a method that uses ultrasound echo groups and artificial neural network(ANN)for reliable on-site real-time identification of material parameters.The use of echo groups allows the use of lower frequencies,and hence more accommodative to structural complexity.To train the ANNs,a numerical model is established that is capable of computing the waveform of ultrasonic echo groups for any given set of material properties of a given structure.The waveform of an ultrasonic echo groups at an interest location on the surface the structure with material parameters varying in a predefined range are then computed using the numerical model.This results in a set of dataset for training the ANN model.Once the ANN is trained,the material parameters can be identified simultaneously using the actual measured echo waveform as input to the ANN.Intensive tests have been conducted both numerically and experimentally to evaluate the effectiveness and accuracy of the currently proposed method.The results show that the maximum identification error of numerical example is less than 2%,and the maximum identification error of experimental test is less than 7%.Compared with currently prevailing methods and equipment,the proposefy the density and thickness,in addition to the elastic constants.Moreover,the reliability and accuracy of inverse prediction is significantly improved.Thus,it has broad applications and enables real-time field measurements,which has not been fulfilled by any other available methods or equipment. 展开更多
关键词 Parameter identification ultrasonic echo group High-precision modeling Artificial neural network NDT
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Microstructure and forming mechanism of metals subjected to ultrasonic vibration plastic forming: A mini review
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作者 Qinghe Cui Xuefeng Liu +4 位作者 Wenjing Wang Shaojie Tian Vasili Rubanik Vasili Rubanik Jr. Dzmitry Bahrets 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1322-1332,共11页
Compared with traditional plastic forming,ultrasonic vibration plastic forming has the advantages of reducing the forming force and improving the surface quality of the workpiece.This technology has a very broad appli... Compared with traditional plastic forming,ultrasonic vibration plastic forming has the advantages of reducing the forming force and improving the surface quality of the workpiece.This technology has a very broad application prospect in industrial manufactur-ing.Researchers have conducted extensive research on the ultrasonic vibration plastic forming of metals and laid a deep foundation for the development of this field.In this review,metals were classified according to their crystal structures.The effects of ultrasonic vibration on the microstructure of face-centered cubic,body-centered cubic,and hexagonal close-packed metals during plastic forming and the mech-anism underlying ultrasonic vibration forming were reviewed.The main challenges and future research direction of the ultrasonic vibra-tion plastic forming of metals were also discussed. 展开更多
关键词 ultrasonic vibration plastic forming crystal structure MICROSTRUCTURE forming mechanism
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Grindability Evaluation of Ultrasonic Assisted Grinding of Silicon Nitride Ceramic Using Minimum Quantity Lubrication Based SiO_(2)Nanofluid
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作者 Yusuf Suleiman Dambatta Changhe Li +8 位作者 Mohd Sayuti Ahmed A D Sarhan Min Yang Benkai Li Anxue Chu Mingzheng Liu Yanbin Zhang Zafar Said Zongming Zhou 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期115-136,共22页
Minimum quantity Lubrication(MQL)is a sustainable lubrication system that is famous in many machining systems.It involve the spray of an infinitesimal amount of mist-like lubricants during machining processes.The MQL ... Minimum quantity Lubrication(MQL)is a sustainable lubrication system that is famous in many machining systems.It involve the spray of an infinitesimal amount of mist-like lubricants during machining processes.The MQL system is affirmed to exhibit an excellent machining performance,and it is highly economical.The nanofluids are understood to exhibit excellent lubricity and heat evacuation capability,compared to pure oil-based MQL system.Studies have shown that the surface quality and amount of energy expended in the grinding operations can be reduced considerably due to the positive effect of these nanofluids.This work presents an experimental study on the tribological performance of SiO_(2)nanofluid during grinding of Si_(3)N_(4)ceramic.The effect different grinding modes and lubrication systems during the grinding operation was also analyzed.Different concentrations of the SiO_(2)nanofluid was manufactured using canola,corn and sunflower oils.The quantitative evaluation of the grinding process was done based on the amount of grinding forces,specific grinding energy,frictional coefficient,and surface integrity.It was found that the canola oil exhibits optimal lubrication performance compared to corn oil,sunflower oil,and traditional lubrication systems.Additionally,the introduction of ultrasonic vibrations with the SiO_(2)nanofluid in MQL system was found to reduce the specific grinding energy,normal grinding forces,tangential grinding forces,and surface roughness by 65%,57%,65%,and 18%respectively.Finally,regression analysis was used to obtain an optimum parameter combinations.The observations from this work will aid the smooth transition towards ecofriendly and sustainable machining of engineering ceramics. 展开更多
关键词 Minimum quantity lubrication(MQL) ultrasonic assisted grinding(UAG) Eco-friendly lubricants NANOFLUID GRINDING CERAMIC
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Theoretical Modeling and Surface Roughness Prediction of Microtextured Surfaces in Ultrasonic Vibration-Assisted Milling
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作者 Chenbing Ni Junjie Zhu +3 位作者 Youqiang Wang Dejian Liu Xuezhao Wang Lida Zhu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期163-183,共21页
Textured surfaces with certain micro/nano structures have been proven to possess some advanced functions,such as reducing friction,improving wear and increasing wettability.Accurate prediction of micro/nano surface te... Textured surfaces with certain micro/nano structures have been proven to possess some advanced functions,such as reducing friction,improving wear and increasing wettability.Accurate prediction of micro/nano surface textures is of great significance for the design,fabrication and application of functional textured surfaces.In this paper,based on the kinematic analysis of cutter teeth,the discretization of ultrasonic machining process,transformation method of coordinate systems and the cubic spline data interpolation,an integrated theoretical model was established to characterize the distribution and geometric features of micro textures on the surfaces machined by different types of ultrasonic vibration-assisted milling(UVAM).Based on the theoretical model,the effect of key process parameters(vibration directions,vibration dimensions,cutting parameters and vibration parameters)on tool trajectories and microtextured surface morphology in UVAM is investigated.Besides,the effect of phase difference on the elliptical shape in 2D/3D ultrasonic elliptical vibration-assisted milling(UEVAM)was analyzed.Compared to conventional numerical models,the method of the cubic spline data interpolation is applied to the simulation of microtextured surface morphology in UVAM,which is more suitable for characterizing the morphological features of microtextured surfaces than traditional methods due to the presence of numerous micro textures.The prediction of surface roughness indicates that the magnitude of ultrasonic amplitude in z-direction should be strictly limited in 1D rotary UVAM,2D and 3D UEVAM due to the unfavorable effect of axial ultrasonic vibration on the surface quality.This study can provide theoretical guidance for the design and fabrication of microtextured surfaces in UVAM. 展开更多
关键词 Theoretical modeling Microtextured surface ultrasonic vibration-assisted milling Cubic spline interpolation Surface roughness
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Damage Evolution of Ballastless Track Concrete Exposed to Flexural Fatigue Loads:The Application of Ultrasonic Pulse Velocity,Impact-echo and Surface Electrical Resistance Method
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作者 杨志强 李化建 +4 位作者 WEN Jiaxing DONG Haoliang HUANG Fali WANG Zhen YI Zhonglai 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期353-363,共11页
In order to clarify the fatigue damage evolution of concrete exposed to flexural fatigue loads,ultrasonic pulse velocity(UPV),impact-echo technology and surface electrical resistance(SR) method were used.Damage variab... In order to clarify the fatigue damage evolution of concrete exposed to flexural fatigue loads,ultrasonic pulse velocity(UPV),impact-echo technology and surface electrical resistance(SR) method were used.Damage variable based on the change of velocity of ultrasonic pulse(Du) and impact elastic wave(Di)were defined according to the classical damage theory.The influences of stress level,loading frequency and concrete strength on damage variable were measured.The experimental results show that Du and Di both present a three-stages trend for concrete exposed to fatigue loads.Since impact elastic wave is more sensitive to the microstructure damage in stage Ⅲ,the critical damage variable,i e,the damage variable before the final fracture of concrete of Di is slightly higher than that of Du.Meanwhile,the evolution of SR of concrete exposed to fatigue loads were analyzed and the relationship between SR and Du,SR and Di of concrete exposed to fatigue loads were established.It is found that the SR of concrete was decreased with the increasing fatigue cycles,indicating that surface electrical resistance method can also be applied to describe the damage of ballastless track concrete exposed to fatigue loads. 展开更多
关键词 ballastless track fatigue damage ultrasonic pulse velocity IMPACT-ECHO surface electrical resistance
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Understanding the spatial interaction of ultrasounds based on three-dimensional dual-frequency ultrasonic field numerical simulation
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作者 Zhao-yang Yin Qi-chi Le +3 位作者 Yan-chao Jiang Da-zhi Zhao Qi-yu Liao Qi Zou 《China Foundry》 SCIE EI CAS CSCD 2024年第1期29-43,共15页
A transient 3D model was established to investigate the effect of spatial interaction of ultrasounds on the dual-frequency ultrasonic field in magnesium alloy melt.The effects of insertion depth and tip shape of the u... A transient 3D model was established to investigate the effect of spatial interaction of ultrasounds on the dual-frequency ultrasonic field in magnesium alloy melt.The effects of insertion depth and tip shape of the ultrasonic rods,input pressures and their ratio on the acoustic field distribution were discussed in detail.Additionally,the spacing,angle,and insertion depth of two ultrasonic rods significantly affect the interaction between distinct ultrasounds.As a result,various acoustic pressure distributions and cavitation regions are obtained.The spherical rods mitigate the longitudinal and transversal attenuation of acoustic pressure and expand the cavitation volume by 53.7%and 31.7%,respectively,compared to the plate and conical rods.Increasing the input pressure will enlarge the cavitation region but has no effect on the acoustic pressure distribution pattern.The acoustic pressure ratio significantly affects the pressure distribution and the cavitation region,and the best cavitation effect is obtained at the ratio of 2:1(P15:P20). 展开更多
关键词 dual-frequency ultrasonic numerical model acoustic pressure spatial interaction magnesium alloy
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Improving fatigue properties of normal direction ultrasonic vibration assisted face grinding Inconel 718 by regulating machined surface integrity
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作者 Nianwei Xu Renke Kang +4 位作者 Bi Zhang Yuan Zhang Chenxu Wang Yan Bao Zhigang Dong 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第3期458-475,共18页
Fatigue properties are crucial for critical aero-engine components in extreme serviceenvironments,which are significantly affected by surface integrity(SI)indexes(especially surface topography,residual stressσ_(res),... Fatigue properties are crucial for critical aero-engine components in extreme serviceenvironments,which are significantly affected by surface integrity(SI)indexes(especially surface topography,residual stressσ_(res),and microhardness)after machining processes.Normal-direction ultrasonic vibration-assisted face grinding(ND-UVAFG)has advantages in improving the machinability of Inconel 718,but there is a competitive relationship between higher compressiveσ_(res)and higher surface roughness R_(a)in affecting fatigue strength.The lack of a quantitative relationship between multiple SI indexes and fatigue strength makes theindeterminacy of a regulatory strategy for improving fatigue properties.In this work,a model of fatigue strength(σ_f)_(sur)considering multiple SI indexes was developed.Then,high-cycle fatigue tests were carried out on Inconel 718 samples with different SI characteristics,and the influence of ND-UVAFG process parameters on SI was analyzed.Based on SI indexes data,the(σ_f)_(sur)distribution in the grinding surface layer for ND-UVAFG Inconel 718 samples was determined using the developed model,and then the fatigue crack initiation(FCI)sites were furtherpredicted.The predicted FCI sites corresponded well with the experimental results,therebyverifying this model.A strategy for improving the fatigue life was proposed in this work,which was to transfer the fatigue source from the machined surface to the bulk material by controlling the SI indexes.Finally,a critical condition of SI indexes that FCI sites appeared on the surface or in bulk material was given by fitting the predicted results.According to the critical condition,an SI field where FCI sites appeared in the bulk material could be obtained.In this field,thefatigue life of Inconel 718 samples could be improved by approximately 140%. 展开更多
关键词 surface integrity fatigue strength Inconel 718 ultrasonic assisted grinding
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Hybrid pedestrian positioning system using wearable inertial sensors and ultrasonic ranging
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作者 Lin Qi Yu Liu +2 位作者 Chuanshun Gao Tao Feng Yue Yu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期327-338,共12页
Pedestrian positioning system(PPS)using wearable inertial sensors has wide applications towards various emerging fields such as smart healthcare,emergency rescue,soldier positioning,etc.The performance of traditional ... Pedestrian positioning system(PPS)using wearable inertial sensors has wide applications towards various emerging fields such as smart healthcare,emergency rescue,soldier positioning,etc.The performance of traditional PPS is limited by the cumulative error of inertial sensors,complex motion modes of pedestrians,and the low robustness of the multi-sensor collaboration structure.This paper presents a hybrid pedestrian positioning system using the combination of wearable inertial sensors and ultrasonic ranging(H-PPS).A robust two nodes integration structure is developed to adaptively combine the motion data acquired from the single waist-mounted and foot-mounted node,and enhanced by a novel ellipsoid constraint model.In addition,a deep-learning-based walking speed estimator is proposed by considering all the motion features provided by different nodes,which effectively reduces the cumulative error originating from inertial sensors.Finally,a comprehensive data and model dual-driven model is presented to effectively combine the motion data provided by different sensor nodes and walking speed estimator,and multi-level constraints are extracted to further improve the performance of the overall system.Experimental results indicate that the proposed H-PPS significantly improves the performance of the single PPS and outperforms existing algorithms in accuracy index under complex indoor scenarios. 展开更多
关键词 Pedestrian positioning system Wearable inertial sensors ultrasonic ranging Deep-learning Data and model dual-driven
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Detection of internal crack growth in polyethylene pipe using guided wave ultrasonic testing
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作者 Jay Kumar Shah Hao Wang Said El-Hawwat 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第2期319-329,共11页
Despite the success of guided wave ultrasonic inspection for internal defect detection in steel pipes,its application on polyethylene(PE)pipe remains relatively unexplored.The growth of internal cracks in PE pipe seve... Despite the success of guided wave ultrasonic inspection for internal defect detection in steel pipes,its application on polyethylene(PE)pipe remains relatively unexplored.The growth of internal cracks in PE pipe severely affects its pressure-holding capacity,hence the early detection of internal cracks is crucial for effective pipeline maintenance strategies.This study extends the scope of guided wave-based ultrasonic testing to detect the growth of internal cracks in a natural gas distribution PE pipe.Laboratory experiments and a finite element model were planned to study the wave-crack interaction at different stages of axially oriented internal crack growth with a piezoceramic transducer-based setup arranged in a pitch-catch configuration.Mode dispersion analysis supplemented with preliminary experiments was performed to isolate the optimal inspection frequency,leading to the selection of the T(0,1)mode at 50-kHz for the investigation.A transmission index based on the energy of the T(0,1)mode was developed to trace the extent of simulated crack growth.The findings revealed an inverse linear correlation between the transmission index and the crack depth for crack growth beyond 20%crack depth. 展开更多
关键词 polyethylene pipes internal cracks guided wave ultrasonic testing torsional modes finite element modeling
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Non-Kramers doublet ground state in a quaternary cubic compound PrRu_(2)In_(2)Zn_(18) investigated by ultrasonic measurements
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作者 张化远 Kazuhei Wakiya +2 位作者 Mitsuteru Nakamura Masahito Yoshizawa Yoshiki Nakanish 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期405-411,共7页
We performed ultrasonic measurements on a quaternary cubic compound PrRu_(2)In_(2)Zn_(18) to explore the ground state properties derived from non-Kramers Γ_(3) doublet of Pr^(3+).PrRu_(2)In_(2)Zn_(18) is a quaternary... We performed ultrasonic measurements on a quaternary cubic compound PrRu_(2)In_(2)Zn_(18) to explore the ground state properties derived from non-Kramers Γ_(3) doublet of Pr^(3+).PrRu_(2)In_(2)Zn_(18) is a quaternary derivative of the ternary compound PrRu_(2)Zn_(20) that exhibits a structural phase transition at T_S=138 K.In PrRu_(2)In_(2)Zn_(18),the Zn atoms at the 16c site in PrRu_(2)Zn_(20) are selectively replaced by In atoms.A monotonic increase was observed in the temperature dependence of elastic constants C_L=(C_(11)+2C_(12)+4C_(44))/3 and C_(T)=(C_(11)-C_(12)+C_(44))/3 in the temperature range around T_(S) to which an elastic softening was observed in(C_(11)-C_(12))/2 for PrRu_(2)Zn_(20).The disappearance of the softening indicates that the structural transition in PrRu_(2)Zn_(20) is suppressed by the substitution of Zn ions by In ones with a larger ionic radius.Alternatively,the C_(T) of PrRu_(2)In_(2)Zn_(18) exhibits a precursor Curie-type elastic softening toward low temperatures being responsible for the non-Kramers Γ_(3) ground state.We discuss the ground state and the evolution of the elastic properties of the different single-crystal samples of PrRu_(2)In_(2)Zn_(18) grown under different conditions. 展开更多
关键词 ultrasonic measurements non-Kramers doublet structural phase transition crystalline electric field effect
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Study on Extraction of Oolong Tea Assisted by Ultrasonic Wave and 4C Technique and Its Application
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作者 Guofeng YU Cuishu LENG +9 位作者 Keli FANG Zhiguang LIU Jianhong SUN Zengyu Wang Xuegang LI Shuai Zhang Jian LIU Xulun WEI Qiulin LIU Shoujie NIE 《Agricultural Biotechnology》 2024年第3期24-27,共4页
[Objectives]The extraction conditions of formula oolong tea were investigated by an orthogonal experiment.[Methods]The technical conditions were optimized by the 4C method,and the application of formula oolong tea ext... [Objectives]The extraction conditions of formula oolong tea were investigated by an orthogonal experiment.[Methods]The technical conditions were optimized by the 4C method,and the application of formula oolong tea extract in cigarettes was studied.[Results]①In the experimental range,the best sensory evaluation effect of formula oolong tea extract was obtained with extraction conditions of 70%ethanol as extraction solvent,extraction time h,extraction temperature 25℃,and ultrasonic frequency 80 kHz,and follow-up low-temperature concentration,low-temperature sedimentation and low-temperature centrifugation.②The effects of different centrifugal speeds on the quality of formula oolong tea extract were explored.The formula oolong tea extract obtained under the conditions of 3000 r/min and centrifugal time of 10 min showed the best evaluation effect with soft and delicate smoke,rich smoke fragrance,good comfort and refreshing mouthfeel.③The effective aroma components in the formula oolong tea extract were qualitatively analyzed by GC-MS.[Conclusions]This study provides high-quality raw materials and a theoretical basis for the research of independent flavor blending in cigarette industry enterprises. 展开更多
关键词 Combined application of ultrasonic wave and 4C technique Orthogonal experiment Formula extraction FLAVOR
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Analysis of Ultrasonic Emulsification Surgery and Small Incision Cataract Extracapsular Extraction Surgery for Cataract Clinical Treatment Level Improvement
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作者 Chunyan Ji 《Journal of Clinical and Nursing Research》 2024年第2期196-200,共5页
Objective:To analyze the efficacy of ultrasonic emulsification and small incision cataract extracapsular extraction in cataract patients.Methods:96 cataract patients admitted from May 2021 to May 2023 were selected an... Objective:To analyze the efficacy of ultrasonic emulsification and small incision cataract extracapsular extraction in cataract patients.Methods:96 cataract patients admitted from May 2021 to May 2023 were selected and randomly grouped into group A(ultrasonic emulsification)and group B(small-incision extracapsular cataract extraction),with 48 cases each.Results:At 1 week,1-month,and 3 months post-operation,the visual acuity of group A was higher and the astigmatism value was lower than that of group B(P<0.05);at 12h,24h,and 48h post-operation,the intraocular pressure of group A was higher than that of group B(P<0.05);the thickness of macular area of group A was lower than that of group B at 1 week and 1-month post-operation(P<0.05).Conclusion:Ultrasonic emulsification in cataract patients was slightly better than small incision cataract extracapsular extraction in correcting astigmatism,improving visual acuity,and regulating macular thickness.However,due to the high energy of ultrasonic emulsification,the risk of complications such as high postoperative intraocular pressure was higher.Small-incision extracapsular cataract extraction has better application value in economically disadvantaged areas. 展开更多
关键词 CATARACT Cataract ultrasonic emulsification Small incision cataract extracapsular extraction Therapeutic efficacy
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Clinical Efficacy of Ultrasonic Medicinal Penetration in the Removal of Blood Stasis and Alleviation of Zhuyu Juanbi Formula in the Treatment of Peripheral Neuropathy Induced by Paclitaxel
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作者 Ying Zhang Huixin Chen +2 位作者 Qirong Zhang Yingjie Jia Dan Yi 《Proceedings of Anticancer Research》 2024年第3期7-17,共11页
Objective: To observe the clinical efficacy and differences of the Zhuyu Juanbi formula delivered through ultrasound at Zusanli on patients with chemotherapy-induced peripheral neuropathy (CIPN) due to paclitaxel inje... Objective: To observe the clinical efficacy and differences of the Zhuyu Juanbi formula delivered through ultrasound at Zusanli on patients with chemotherapy-induced peripheral neuropathy (CIPN) due to paclitaxel injection. Methods: A total of 72 breast cancer patients with CIPN were randomly divided into two groups. The treatment group (36 cases) was treated with oral methylcobalamin plus ultrasonic medicine permeating Zhuyu Juanbi formulae, while the control group (36 cases) was treated with oral methylcobalamin alone. Following two 2 cycles of continuous treatment, the efficacy of peripheral neurotoxicity, TCM syndrome score, FACT/GOG-Ntx score, total neuropathy score, and safety indicators of gynecological cancer patients were observed in the two groups. Result: In the treatment of CIPN, the addition of ultrasonic medicine permeating Zhuyu Juanbi formulae was more effective than oral methylcobalamin alone in reducing peripheral neurotoxicity and improving the quality of life of patients. The difference between the two groups was statistically significant (P < 0.05), and ultrasound drug penetration Zhuyu Juanbi formulae significantly reduced the FACT/ GOG-Ntx score and TNS score in the treatment group. In terms of drug safety, it rarely caused adverse reactions such as grade 3 and 4 leukopenia, and the safety profile was therefore good. Conclusion: The combination of ultrasonic medicine permeating Zhuyu Juanbi formulae and methylcobalamin has been demonstrated to be an effective treatment for peripheral neurotoxicity in patients with PIPN. It has been shown to significantly improve the clinical symptoms of PIPN patients, improve the quality of life of patients, and have a good safety profile. 展开更多
关键词 Chemotherapy-induced peripheral neuropathy(CIPN) Paclitaxel-induced peripheral neuropathy Zhuyu Juanbi formulae ultrasonic drug delivery
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Applications of Ultrasonic Detection Technology in Bridge Concrete Pile Foundation Detection
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作者 Wei Fu 《Journal of World Architecture》 2023年第6期45-50,共6页
In this paper,the application strategy of ultrasonic detection technology in the detection of concrete foundation piles is analyzed using a construction project as an example.It includes a basic overview of the projec... In this paper,the application strategy of ultrasonic detection technology in the detection of concrete foundation piles is analyzed using a construction project as an example.It includes a basic overview of the project,an overview of ultrasonic testing technology in bridge concrete pile foundation testing,and an analysis of its practical application in the concrete pile foundation testing of this project.The objective of this analysis is to provide some reference for the application of ultrasonic testing technology and the improvement of the quality of bridge concrete pile foundation testing. 展开更多
关键词 Bridge engineering Concrete pile foundation ultrasonic detection technology ultrasonic detection principle
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Simultaneous measurement of velocity profile and liquid film thickness in horizontal gas–liquid slug flow by using ultrasonic Doppler method 被引量:1
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作者 Lusheng Zhai Bo Xu +1 位作者 Haiyan Xia Ningde Jin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第6期323-340,共18页
Horizontal gas-liquid two-phase flows widely exist in chemical engineering,oil/gas production and other important industrial processes.Slug flow pattern is the main form of horizontal gas-liquid flows and characterize... Horizontal gas-liquid two-phase flows widely exist in chemical engineering,oil/gas production and other important industrial processes.Slug flow pattern is the main form of horizontal gas-liquid flows and characterized by intermittent motion of film region and slug region.This work aims to develop the ultrasonic Doppler method to realize the simultaneous measurement of the velocity profile and liquid film thickness of slug flow.A single-frequency single-channel transducer is adopted in the design of the field-programmable gate array based ultrasonic Doppler system.A multiple echo repetition technology is used to improve the temporal-spatial resolution for the velocity profile.An experiment of horizontal gas-liquid two-phase flow is implemented in an acrylic pipe with an inner diameter of 20 mm.Considering the aerated characteristics of the liquid slug,slug flow is divided into low-aerated slug flow,high-aerated slug flow and pseudo slug flow.The temporal-spatial velocity distributions of the three kinds of slug flows are reconstructed by using the ultrasonic velocity profile measurement.The evolution characteristics of the average velocity profile in slug flows are investigated.A novel method is proposed to derive the liquid film thickness based on the instantaneous velocity profile.The liquid film thickness can be effectively measured by detecting the position and the size of the bubbles nearly below the elongated gas bubble.Compared with the time of flight method,the film thickness measured by the Doppler system shows a higher accuracy as a bubble layer occurs in the film region.The effect of the gas distribution on the film thickness is uncovered in three kinds of slug flows. 展开更多
关键词 Gas–liquid flow Complex fluids Measurement ultrasonic Doppler Velocity profile Liquid film thickness
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Structure and allergenicity of a-lactalbumin:effects of ultrasonic prior to glycation and subsequent phosphorylation 被引量:1
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作者 Wenmei Chen Qiongzhen Chen +4 位作者 Houze Zhou Yanhong Shao Yang Wang Jun Liu Zongcai Tu 《Food Science and Human Wellness》 SCIE CSCD 2023年第3期825-831,共7页
Bovineα-lactalbumin(BLA)induced severe cow's milk allergy.In this study,a novel strategy combining ultrasonication,performed before glycation,and phosphorylation was proposed to reduce BLA allergenicity.Result sh... Bovineα-lactalbumin(BLA)induced severe cow's milk allergy.In this study,a novel strategy combining ultrasonication,performed before glycation,and phosphorylation was proposed to reduce BLA allergenicity.Result showed that IgE-and IgG-binding capacities and the release rates of histamine and interleukin-6 from RBL-2 H3 were reduced.Moreover,intrinsic fluorescence intensity and surface hydrophobicity were decreased,whereas glycated sites(R10,N44,K79,K108,N102 and K114)and phosphorylated sites(Y36 and S112)of BLA were increased.Minimum allergenicity was detected during BLA treatment after ultrasonic prior to glycation and subsequent phosphorylation because of considerable increase in glycated and phosphorylated sites.Therefore,the decrease in allergenicity of BLA,the effect correlated well with the shielding effect of glycated sites combined with phosphorylated sites and the conformational changes.This study provides important theoretical foundations for improving and using the ultrasonic technology combined with protein modification in allergenic protein processing. 展开更多
关键词 Bovineα-lactalbumin ALLERGENICITY ultrasonic Protein modification
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Mechanism of ultrasonic strengthening fluidity of low mature shale oil: A case study of the first member of Lucaogou Formation, western Jimusaer Sag, Northwest China
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作者 Bo-Yang Wang Bo Liu +1 位作者 Yun-Fei Cui Zi-Long Wang 《Petroleum Science》 SCIE EI CAS CSCD 2023年第6期3337-3347,共11页
The low mature shale oil resources of Lucaogou Formation in Jimusar Sag have a great potential, but the heavy oil quality limits large-scale economic development significantly. Ultrasonic is a typical representative o... The low mature shale oil resources of Lucaogou Formation in Jimusar Sag have a great potential, but the heavy oil quality limits large-scale economic development significantly. Ultrasonic is a typical representative of heavy oil viscosity reduction and anhydrous fracturing technology, and how to understand the action characteristics and mechanism of ultrasonic effect on reservoir is a critical issue to enhance shale oil production in the industrialized application of power ultrasonic. Therefore, the comparative experiments with different time of power ultrasonic loading were conducted to analyze the response mechanism of reservoir characteristics and the change of fluid mobility. The results indicate that the ultrasonic treatment is ameliorative to the pore-fracture structure, and the improvement degree is controlled by the mechanical vibration and cavitation of ultrasound. Generally, the location with weak cementation strength or relatively developed microcrack is preferred to pore expansion. After the ultrasonic treatment, the shale oil quality becomes lighter, and the transformation of shale oil from adsorbed to free, is accelerated due to enhanced fluidity. Pore-expanding effect and fluid mobility enhancement are essential aspects of the power ultrasonic loading to improve the recovery of low mature shale oil. The results of this study support the feasibility analysis of ultrasonic enhanced shale oil exploitation theoretically. 展开更多
关键词 ultrasonic Shale oil Reservoir properties Mobility Recovery
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A Wire-Driven Series Elastic Mechanism Based on Ultrasonic Motor for Walking Assistive System
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作者 Weihao Ren Hiroki Yoshioka +1 位作者 Lin Yang Takeshi Morita 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第3期179-190,共12页
In order to improve the elderly people's quality of life,supporting their walking behaviors is a promising technology.Therefore,based on one ultrasonic motor,a wire-driven series elastic mechanism for walking assi... In order to improve the elderly people's quality of life,supporting their walking behaviors is a promising technology.Therefore,based on one ultrasonic motor,a wire-driven series elastic mechanism for walking assistive system is proposed and investigated in this research.In contrast to tradition,it innovatively utilizes an ultrasonic motor and a wire-driven series elastic mechanism to achieve superior system performances in aspects of simple structure,high torque/weight ratio,quiet operation,quick response,favorable electromagnetic compatibility,strong shock resistance,better safety,and accurately stable force control.The proposed device is mainly composed of an ultrasonic motor,a linear spring,a steel wire,four pulleys and one rotating part.To overcome the ultrasonic motor's insufficient output torque,a steel wire and pulleys are smartly combined to directly magnify the torque instead of using a conventional gear reducer.Among the pulleys,there is one tailored pulley playing an important role to keep the reduction ratio as 4.5 constantly.Meanwhile,the prototype is manufactured and its actual performance is verified by experimental results.In a one-second operating cycle,it only takes 86 ms for this mechanism to output an assistive torque of 1.6 N·m.At this torque,the ultrasonic motor's speed is around 4.1 rad/s.Moreover,experiments with different operation periods have been conducted for different application scenarios.This study provides a useful idea for the application of ultrasonic motor in walking assistance system. 展开更多
关键词 ultrasonic motor WIRE-DRIVEN Series elastic mechanism Walking assistive system Pulley Reduction ratio
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Modeling the hydration,viscosity and ultrasonic property evolution of class G cement up to 90℃ and 200 MPa by a scale factor method
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作者 Li-Jun Sun Xue-Yu Pang +1 位作者 Siavash Ghabezloo Hai-Bing Yan 《Petroleum Science》 SCIE EI CAS CSCD 2023年第4期2372-2385,共14页
A comprehensive experimental program has been performed to characterize the hydration and engineering property evolution of a class G oil well cement under various curing temperatures from 30 to 90℃.The progress of h... A comprehensive experimental program has been performed to characterize the hydration and engineering property evolution of a class G oil well cement under various curing temperatures from 30 to 90℃.The progress of hydration was monitored by isothermal calorimetry(atmospheric pressure);the viscosity evolution was measured using a high temperature and high pressure consistometer(up to 200 MPa);the ultrasonic property development was evaluated by an ultrasonic cement analyzer(up to 100 MPa).Test results indicate that the influences of curing temperature and pressure on the hydration,viscosity and ultrasonic property development can be modeled by a scale factor method that is similar to the maturity method used in the concrete industry.However,the key parameters of the scale factor model,namely the apparent activation energy and the apparent activation volume of cement showed obvious variations with test method and curing condition.The test results indicate that the curing temperature has a stronger effect on cement hydration rate than viscosity and ultrasonic property development rate,while the curing pressure has a much stronger influence on cement slurry properties before setting(viscosity)than after setting(ultrasonic property). 展开更多
关键词 Activation energy Activation volume Isothermal calorimetry CONSISTENCY ultrasonic property
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Microstructure Transformation and Refinement Mechanism of Undercooled Cu-Ni-Co Alloy Based on Simulation of Critical Cutting Speed in Ultrasonic Machining
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作者 HE Xiaoyu HOU Kai +2 位作者 XU Xuguang TANG Cheng ZHU Xijing 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第6期1472-1483,共12页
Both Cu60Ni38Co2 and Cu60Ni40 alloy were naturally cooled after rapid solidification from the liquid phase.The transformation law of the microstructure characteristics of the rapidly solidified alloy with the change o... Both Cu60Ni38Co2 and Cu60Ni40 alloy were naturally cooled after rapid solidification from the liquid phase.The transformation law of the microstructure characteristics of the rapidly solidified alloy with the change of undercooling(ΔT)was systematically studied.It is found that the two alloys experience the same transformation process.The refinement structures under different undercoolings were characterized by electron backscatter diffraction(EBSD).The results show that the characteristics of the refinement structure of the two alloys with low undercooling are the same,but the characteristics of the refinement structure with high undercooling are opposite.The transmission electron microscopy(TEM)results of Cu60Ni38Co2 alloy show that the dislocation network density of low undercooled microstructure is lower than that of high undercooled microstructure.By combining EBSD and TEM,it could be confirmed that the dendrite remelting fracture is the reason for the refinement of the low undercooled structure,while the high undercooled structure is refined due to recrystallization.On this basis,in the processing of copper base alloys,there will be serious work hardening phenomenon and machining hard problem of consciousness problems caused by excessive cutting force.A twodimensional orthogonal turning finite element model was established using ABAQUS software to analyze the changes in cutting speed and tool trajectory in copper based alloy ultrasonic elliptical vibration turning.The results show that in copper based alloy ultrasonic elliptical vibration turning,cutting process parameters have a significant impact on cutting force.Choosing reasonable process parameters can effectively reduce cutting force and improve machining quality. 展开更多
关键词 rapid solidification UNDERCOOLING microstructure refinement structure ultrasonic elliptical vibration turning cutting speed finite element analysis
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