Conventional four-probe methods for measuring the resistance of Josephson junctions can damage superconducting thin films,making them unsuitable for frequency measurements of superconducting qubits.In this study,we pr...Conventional four-probe methods for measuring the resistance of Josephson junctions can damage superconducting thin films,making them unsuitable for frequency measurements of superconducting qubits.In this study,we present a custom probe station measurement system that employs the fritting contact technique to achieve in situ,non-destructive measurements of Josephson junction resistance.Our experimental results demonstrate that this method allows for accurate prediction of qubit frequency with an error margin of 17.2 MHz.Moreover,the fritting contact technique does not significantly affect qubit coherence time or the integrity of the superconducting film,confirming its non-destructive nature.This innovative approach provides a dependable foundation for frequency tuning and addressing frequency collision issues,thus supporting the advancement and practical deployment of superconducting quantum computing.展开更多
Longitudinal joint construction quality is critical to the life of flexible pavements.Maintaining deteriorated longitudinal joints has become a challenge for many highway agencies.Improving the joint's quality thr...Longitudinal joint construction quality is critical to the life of flexible pavements.Maintaining deteriorated longitudinal joints has become a challenge for many highway agencies.Improving the joint's quality through better compaction during construction can help achieve flexible pavements with longer service lives and less maintenance.Current quality control(QC)and quality assurance(QA)plans provide limited coverage.Consequently,the risk of missing areas with poor joint compaction is significant.A density profiling system(DPS)is a non-destructive alternative to conventional destructive evaluation methods.It can provide quick and continuous real-time coverage of the compaction during construction in dielectrics.The paper presents several case studies comparing various types of longitudinal joints and demonstrating the use of DPS to evaluate the joint's compaction quality.The paper shows that dielectric measurements can provide valuable insight into the ability of various construction techniques to achieve adequate levels of compaction at the longitudinal joint.The paper proposes a dielectric-based longitudinal joint quality index(LJQI)to evaluate the relative compaction of the joint during construction.It also shows that adopting DPS for assessing the compaction of longitudinal joints can minimize the risk of agencies accepting poorly constructed joints,identify locations of poor quality during construction,and achieve better-performing flexible pavements.展开更多
This article takes the actual construction project of a certain concrete bridge project as an example to analyze the application of acoustic non-destructive testing technology in its detection.It includes an overview ...This article takes the actual construction project of a certain concrete bridge project as an example to analyze the application of acoustic non-destructive testing technology in its detection.It includes an overview of a certain bridge construction project studied and acoustic non-destructive testing technology and the application of acoustic non-destructive testing technology in actual testing.This analysis hopes to provide some guidelines for acoustic non-destructive testing of modern concrete bridge projects.展开更多
Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in China.In vine tea processing,a large amount of broken tea is produced,which has low commercial value.Methods:This study investigat...Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in China.In vine tea processing,a large amount of broken tea is produced,which has low commercial value.Methods:This study investigates the influence of different extraction methods(room temperature water extraction,boiling water extraction,ultrasonic-assisted room temperature water extraction,and ultrasonic-assisted boiling water extraction,referred to as room temperature water extraction(RE),boiling water extraction(BE),ultrasonic assistance at room temperature water extraction(URE),and ultrasonic assistance in boiling water extraction(UBE))on the yield,dihydromyricetin(DMY)content,free amino acid composition,volatile aroma components,and antioxidant properties of vine tea extracts.Results:A notable influence of extraction temperature on the yield of vine tea extracts(P<0.05),with BE yielding the highest at 43.13±0.26%,higher than that of RE(34.29±0.81%).Ultrasound-assisted extraction significantly increased the DMY content of the extracts(P<0.05),whereas DMY content in the RE extracts was 59.94±1.70%,that of URE reached 66.14±2.78%.Analysis revealed 17 amino acids,with L-serine and aspartic acid being the most abundant in the extracts,nevertheless ultrasound-assisted extraction reduced total free amino acid content.Gas chromatography-mass spectrometry analysis demonstrated an increase in the diversity and quantity of compounds in the vine tea water extracts obtained through ultrasonic-assisted extraction.Specifically,69 and 68 volatile compounds were found in URE and UBE extracts,which were higher than the number found in RE and BE extracts.In vitro,antioxidant activity assessments revealed varying antioxidant capacities among different extraction methods,with RE exhibiting the highest DPPH scavenging rate,URE leading in ABTS•+free radical scavenging,and BE demonstrating superior ferric ion reducing antioxidant activity.Conclusion:The findings suggest that extraction methods significantly influence the chemical composition and antioxidant properties of vine tea extracts.Ultrasonic-assisted extraction proved instrumental in elevating the DMY content in vine tea extracts,thereby enriching its flavor profile while maintaining its antioxidant properties.展开更多
Phase aberration correction for medical ultrasound systems has attracted a great deal of attention. Since phased array techniques are now widely employed for industrial non-destructive testing (NDT) applications in ...Phase aberration correction for medical ultrasound systems has attracted a great deal of attention. Since phased array techniques are now widely employed for industrial non-destructive testing (NDT) applications in various fields, the problem of phase aberrations in the process of NDT testing is considered. The technique of cross-covariance for phase aberration correction is presented. The performance of the technique for phase aberration correction is tested by means of echo signals obtained in practical non-destructive testing experiment. The results show that the technique has the better accuracy of phase correction.展开更多
Pulsed eddy current (PEC) non-destructive test- ing and evaluation (NDT&E) has been around for some time and it is still attracting extensive attention from researchers around the globe, which can be witnessed th...Pulsed eddy current (PEC) non-destructive test- ing and evaluation (NDT&E) has been around for some time and it is still attracting extensive attention from researchers around the globe, which can be witnessed through the reports reviewed in this paper. Thanks to its richness of spectral components, various applications of this technique have been proposed and reported in the lit- erature covering both structural integrity inspection and material characterization in various industrial sectors. To support its development and for better understanding of the phenomena around the transient induced eddy currents, attempts for its modelling both analytically and numeri- cally have been made by researchers around the world. This review is an attempt to capture the state-of-the-art development and applications of PEC, especially in the last 15 years and it is not intended to be exhaustive. Future challenges and opportunities for PEC NDT&E are also presented.展开更多
In recent years, advanced composite structures are used extensively in many industries such as aerospace, aircraft, automobile, pipeline and civil engineering. Reliability and safety are crucial requirements posed by ...In recent years, advanced composite structures are used extensively in many industries such as aerospace, aircraft, automobile, pipeline and civil engineering. Reliability and safety are crucial requirements posed by them to the advanced composite structures be- cause of their harsh working conditions. Therefore, as a very important measure, structural health monitoring (SHM) in-service is deft- nitely demanded for ensuring their safe working in-situ. In this paper, fiber Bragg grating (FBG) sensors are surface-mounted on the hoop and in the axial directions of a FRP pressure vessel to monitor the strain status during its pressurization. The experimental results show that the FBG sensors could be used to monitor the strain development and determine the ultimate failure strain of the composite pressure vessel.展开更多
Aiming at the problems of low reliability and complex operation of traditional coin-tap test of composite material,this paper introduces the grey system theory and achieves better performance.The response signals of c...Aiming at the problems of low reliability and complex operation of traditional coin-tap test of composite material,this paper introduces the grey system theory and achieves better performance.The response signals of coin-tap are classified through the grey clustering based on relation analysis,and corresponding improvements are made to the calculation method of the relation degree of nearness.First,the time history of acceleration is taken as the system behavior sequence.The improved correlation calculation method is used to solve the relation degree of nearness between the sequences,and the matrix of degree of grey relation is constructed based on this.Then,the sequence groups are summarized through the matrix,and the response signals of coin-tap are qualitatively classified according to the location of the reference sequence.Finally,the defect detection of composite materials is completed without pre-testing.The test results show that the accuracy of the coin-tap test based on improved grey clustering reaches 100%,which simplifies the operation steps while ensuring the reliability of the coin-tap test results.展开更多
Non-destructive testing (NDT) of structures is one of the most important tasksof the proper maintenance and diagnosis of machines and constructions structuralcondition. NDT methods contribute to the damage tolerance p...Non-destructive testing (NDT) of structures is one of the most important tasksof the proper maintenance and diagnosis of machines and constructions structuralcondition. NDT methods contribute to the damage tolerance philosophy used in theaircraft design methodology as well as many other operation and maintenance programsof machinery and constructions. The following study is focusing on overviewing animportant group of NDT methods: the optical and other ones, which found broadapplicability in scientific and industrial studies nowadays. The paper discusses theselected most widely applicable methods, namely, visual testing, ultrasonic testing,radiographic testing, infrared thermography as well as electronic speckle patterninterferometry and shearographic testing. Besides the basic principles of testing usingthese methods, their potential applications in various industrial and technologicalbranches are broadly discussed. The analysis as categorization of the NDT methodsprovided in this paper may help in selection of such methods in diagnosis of varioustypes of structures and defects and damage occurring in these structures.展开更多
The characterization of ultra-soft clayey soil exhibits extreme challenges due to low shear strength of such material.Hence,inspecting the non-destructive electrical impedance behavior of untreated and treated ultra-s...The characterization of ultra-soft clayey soil exhibits extreme challenges due to low shear strength of such material.Hence,inspecting the non-destructive electrical impedance behavior of untreated and treated ultra-soft clayey soils gains more attention.Both shear strength and electrical impedance were measured experimentally for both untreated and treated ultra-soft clayey soils.The shear strength of untreated ultra-soft clayey soil reached 0.17 kPa for 10% bentonite content,while the shear strengths increased to 0.27 kPa and 6.7 kPa for 10% bentonite content treated with 2% lime and 10% polymer,respectively.The electrical impedance of the ultra-soft clayey soil has shown a significant decrease from 1.6 kΩ to 0.607 kΩ when the bentonite content increased from 2% to 10% at a frequency of 300 kHz.The10%lime and 10% polymer treatments have decreased the electrical impedances of ultra-soft clayey soil with 10%bentonite from 0.607 kΩ to 0.12 kΩ and 0.176 kΩ,respectively,at a frequency of 300 kHz.A new mathematical model has been accordingly proposed to model the non-destructive electrical impedancefrequency relationship for both untreated and treated ultra-soft clayey soils.The new model has shown a good agreement with experimental data with coefficient of determination(R;)up to 0.99 and root mean square error(RMSE) of 0.007 kΩ.展开更多
Wheat quality detection is essential to ensure the safety ofwheat circulation and storage.The traditional wheat quality detection methods mainly include artificial sensory evaluation and physicochemical index analysis...Wheat quality detection is essential to ensure the safety ofwheat circulation and storage.The traditional wheat quality detection methods mainly include artificial sensory evaluation and physicochemical index analysis,which are difficult to meet the requirements for high accuracy and efficiency in modern wheat quality detection due to the disadvantages of subjectivity,destruction of sample integrity and low efficiency.With the rapid development of optical technology,various optical-based methods,using near-infrared spectroscopy technology,hyperspectral imaging technology and terahertz,etc.,have been proposed for wheat quality detection.These methods have the characteristics of nondestructiveness and high efficiency which make them popular in wheat quality detection in recent years.In this paper,various state-of-the-art optical-based techniques of wheat quality detection are analyzed and summarized in detail.Firstly,the principle and process of common optical non-destructive detection methods for wheat quality are introduced.Then,the optical techniques used in these detection methods are divided into seven categories,and the comparison of these technologies and their advantages and disadvantages are further discussed.It shows that terahertz technology is regarded as the most promising wheat quality detection method compared with other optical detection technologies,because it can not only detect most types of wheat deterioration,but also has higher accuracy and efficiency.Finally,the research of optical technology in wheat quality detection is prospected.The future research of optical technology-based wheat quality detection mainly includes the construction of wheat quality optical detection standardization database,the fusion of multiple optical detection technologies and multiple quality index information,the improvement of the anti-interference of optical technology and the industrialization of optical inspection technology for wheat quality.These studies are of great significance to improve the detection technology of wheat and ensure the storage safety of wheat in the future.展开更多
Accurate assessment of herbage mass (HM) in pasture is a key to budgeting forage in grazing systems worldwide. Different non-destructive techniques to measuring pasture yield are commented. The methods compared incl...Accurate assessment of herbage mass (HM) in pasture is a key to budgeting forage in grazing systems worldwide. Different non-destructive techniques to measuring pasture yield are commented. The methods compared include visual estimations, manual and electronic pasture meters and remote sensing. All methods are associated with a moderate to high error, showing that some indirect methods of yield estimation are appropriate under most appropriate because many factors as climate variations, soil certain conditions. In general terms, no method was found as the characteristics, plant phenology, pasture management and species composition must be taken into account to make local calibrations from a general model. Best results were found modifying general methods under local calibrations and under local conditions. In order to give farmers the best method to manage adequately their own grazing systems, researchers must select the most suitable technique considering the scale of operation, the desired accuracy and the resources available.展开更多
Optoelectronic terahertz generation and detection play a key role in the applications of non-destructive testing,which involves different areas such as physics,biological,material science,imaging,explosions detection,...Optoelectronic terahertz generation and detection play a key role in the applications of non-destructive testing,which involves different areas such as physics,biological,material science,imaging,explosions detection,astronomy applications,semiconductor technology and superconductiong electronics. In this article,we present a reviewof the principle and performance of typical terahertz sources,detectors and non-destructive testing applications. On this basis,the newdevelopment and trends of terahertz radiation detectors are also discussed.展开更多
In this study, water permeation through cementitious materials was observed using magnetic resonance imaging (MRI). The influence of cement type on the magnetic resonance signal was studied subsequent to determining t...In this study, water permeation through cementitious materials was observed using magnetic resonance imaging (MRI). The influence of cement type on the magnetic resonance signal was studied subsequent to determining the parameters required for imaging. Consequently, adequate imaging of water permeating through hardened cement paste (HCP) made with white Portland cement was achieved, while water permeation through ordinary Portland cement-based HCP yielded poor signal. HCPs maintained at various levels of relative humidity (RH) were observed, and the signal was detected only from those maintained at an RH of higher than 85%. The water permeation depths in HCP were observed by using MRI, and the measured depths were compared to those measured via a spraying water detector on the split surface of the specimens. As a result, good agreement was confirmed between the two methods. Additionally, MRI was applied to concrete specimens;although it was found that water was not detected when a lightweight aggregate was used, water permeation through concrete with limestone aggregate was detectable via MRI. MRI will help in understanding how water permeation causes and accelerates concrete deteriorations such as rebar corrosion and freezing and thawing.展开更多
This study was undertaken to investigate the feasibility of near-infrared(NIR) hyperspectral imaging(1 000–2 500 nm) for non-destructive and quantitative prediction of protein content in peanut kernels. Partial least...This study was undertaken to investigate the feasibility of near-infrared(NIR) hyperspectral imaging(1 000–2 500 nm) for non-destructive and quantitative prediction of protein content in peanut kernels. Partial least squares regression(PLSR) calibration model was established between the spectral data extracted from the hyperspectral images and the reference measured protein content values, with the coefficient of determination of prediction(R_P^2) of 0.885 and root mean square error of prediction(RMSEP) of 0.465%.Regression coefficients(RC) from PLSR analysis were used to identify the most essential wavelengths that had the greatest influence on changes in the protein content. Eight optimal wavelengths were selected by RC and its corresponding simplified RC-PLSR prediction model was also obtained, showing better performance with a higher R_P^2 of 0.870 and a lower RMSEP of 0.494%. The results indicate that hyperspectral imaging with PLSR analysis can be used as a rapid and non-destructive method for predicting protein content in peanut.展开更多
Ground Penetrating Radar(GPR) is an effective Non-Destructive Testing(NDT) technique for highway pavement surveys, which is able to acquire continuous pavement data compared with traditional core drilling method. In t...Ground Penetrating Radar(GPR) is an effective Non-Destructive Testing(NDT) technique for highway pavement surveys, which is able to acquire continuous pavement data compared with traditional core drilling method. In this study, we proposed an accurate and efficient method to estimate the thickness of each pavement layer using an air-coupled GPR system. For this work, the main difficulties are estimating each pavement layer's time delay and dielectric constant. We first give the basic signal model for pavement evaluation, and then present an Intrinsic Mode Functions(IMFs) product detector to determine each pavement layer's time delay. This method is based on Empirical Mode Decomposition(EMD), which is an adaptive signal decomposition procedure and proved to be suitable for suppressing noises in GPR signal. The dielectric constant was determined by metal reflection measurement. The laboratory and highway experiments illustrate that the proposed thickness estimation method yields reasonable result, thus meets the requirements of practical highway pavement survey with massive GPR data.展开更多
This paper introduces recent research work in the field of pulsed electromagnetic non-destructive testing/evaluation.These are pulsed eddy current,pulsed magnetic flux leakage and eddy current pulsed thermography.This...This paper introduces recent research work in the field of pulsed electromagnetic non-destructive testing/evaluation.These are pulsed eddy current,pulsed magnetic flux leakage and eddy current pulsed thermography.This paper introduces pulsed electromagnetic techniques and their different case studies on defect detection as well as stress characterisation.Experimental tests have been validated and future research plans are discussed.This paper demonstrates pulsed electromagnetic non-destructive testing and evaluation for not only depth information,but also for multiple parameter measurement and multiple integration,which are important for future development.展开更多
Background Ginkgo biloba extract(GBE)is evidenced to be effective in the prevention and alleviation of metabolic disorders,including obesity,diabetes and fatty liver disease.However,the role of GBE in alleviating fatt...Background Ginkgo biloba extract(GBE)is evidenced to be effective in the prevention and alleviation of metabolic disorders,including obesity,diabetes and fatty liver disease.However,the role of GBE in alleviating fatty liver hemorrhagic syndrome(FLHS)in laying hens and the underlying mechanisms remain to be elucidated.Here,we investigated the effects of GBE on relieving FLHS with an emphasis on the modulatory role of GBE in chicken gut microbiota.Results The results showed that GBE treatment ameliorated biochemical blood indicators in high-fat diet(HFD)-induced FLHS laying hen model by decreasing the levels of TG,TC,ALT and ALP.The lipid accumulation and pathological score of liver were also relieved after GBE treatment.Moreover,GBE treatment enhanced the antioxidant activity of liver and serum by increasing GSH,SOD,T-AOC,GSH-PX and reducing MDA,and downregulated the expression of genes related to lipid synthesis(FAS,LXRα,GPAT1,PPARγand Ch REBP1)and inflammatory cytokines(TNF-α,IL-6,TLR4 and NF-κB)in the liver.Microbial profiling analysis revealed that GBE treatment reshaped the HFD-perturbed gut microbiota,particularly elevated the abundance of Megasphaera in the cecum.Meanwhile,targeted metabolomic analysis of SCFAs revealed that GBE treatment significantly promoted the production of total SCFAs,acetate and propionate,which were positively correlated with the GBE-enriched gut microbiota.Finally,we confirmed that the GBE-altered gut microbiota was sufficient to alleviate FLHS by fecal microbiota transplantation(FMT).Conclusions We provided evidence that GBE alleviated FLHS in HFD-induced laying hens through reshaping the composition of gut microbiota.Our findings shed light on mechanism underlying the anti-FLHS efficacy of GBE and lay foundations for future use of GBE as additive to prevent and control FLHS in laying hen industry.展开更多
In this paper single ultra-fast voltage pulses are introduced to the Pt/Ir tip of a scanning tunnelling microscope (STM), and the non-destructive threshold of the graphite surface is studied systematically in a wide...In this paper single ultra-fast voltage pulses are introduced to the Pt/Ir tip of a scanning tunnelling microscope (STM), and the non-destructive threshold of the graphite surface is studied systematically in a wide range of pulse durations (from 104 to 8 ns). Considering the waveform distortion of the pulses at the tunnelling region, this paper gives the corrected threshold curve of pulse amplitude depending on pulse duration. A new explanation of threshold power has been suggested and fits the experimental results well.展开更多
Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinat...Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinations is more significant than a specific food component.This study investigated the lipid-lowering effect of highland barley polyphenols via lipase assay in vitro and HepG2 cells induced by oleic acid(OA).Five indexes,triglyceride(TG),total cholesterol(T-CHO),low density lipoprotein-cholesterol(LDL-C),aspartate aminotransferase(AST),and alanine aminotransferase(ALT),were used to evaluate the lipidlowering effect of highland barley extract.We also preliminary studied the lipid-lowering mechanism by Realtime fluorescent quantitative polymerase chain reaction(q PCR).The results indicated that highland barley extract contains many components with lipid-lowering effects,such as hyperoside and scoparone.In vitro,the lipase assay showed an 18.4%lipase inhibition rate when the additive contents of highland barley extract were 100μg/m L.The intracellular lipid-lowering effect of highland barley extract was examined using 0.25 mmol/L OA-induced HepG2 cells.The results showed that intracellular TG,LDL-C,and T-CHO content decreased by 34.4%,51.2%,and 18.4%,respectively.ALT and AST decreased by 51.6%and 20.7%compared with the untreated hyperlipidemic HepG2 cells.q PCR results showed that highland barley polyphenols could up-regulation the expression of lipid metabolism-related genes such as PPARγand Fabp4.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12034018 and 11625419).
文摘Conventional four-probe methods for measuring the resistance of Josephson junctions can damage superconducting thin films,making them unsuitable for frequency measurements of superconducting qubits.In this study,we present a custom probe station measurement system that employs the fritting contact technique to achieve in situ,non-destructive measurements of Josephson junction resistance.Our experimental results demonstrate that this method allows for accurate prediction of qubit frequency with an error margin of 17.2 MHz.Moreover,the fritting contact technique does not significantly affect qubit coherence time or the integrity of the superconducting film,confirming its non-destructive nature.This innovative approach provides a dependable foundation for frequency tuning and addressing frequency collision issues,thus supporting the advancement and practical deployment of superconducting quantum computing.
文摘Longitudinal joint construction quality is critical to the life of flexible pavements.Maintaining deteriorated longitudinal joints has become a challenge for many highway agencies.Improving the joint's quality through better compaction during construction can help achieve flexible pavements with longer service lives and less maintenance.Current quality control(QC)and quality assurance(QA)plans provide limited coverage.Consequently,the risk of missing areas with poor joint compaction is significant.A density profiling system(DPS)is a non-destructive alternative to conventional destructive evaluation methods.It can provide quick and continuous real-time coverage of the compaction during construction in dielectrics.The paper presents several case studies comparing various types of longitudinal joints and demonstrating the use of DPS to evaluate the joint's compaction quality.The paper shows that dielectric measurements can provide valuable insight into the ability of various construction techniques to achieve adequate levels of compaction at the longitudinal joint.The paper proposes a dielectric-based longitudinal joint quality index(LJQI)to evaluate the relative compaction of the joint during construction.It also shows that adopting DPS for assessing the compaction of longitudinal joints can minimize the risk of agencies accepting poorly constructed joints,identify locations of poor quality during construction,and achieve better-performing flexible pavements.
文摘This article takes the actual construction project of a certain concrete bridge project as an example to analyze the application of acoustic non-destructive testing technology in its detection.It includes an overview of a certain bridge construction project studied and acoustic non-destructive testing technology and the application of acoustic non-destructive testing technology in actual testing.This analysis hopes to provide some guidelines for acoustic non-destructive testing of modern concrete bridge projects.
基金supported by the Key Research and Development Program of Hunan Province of China(No.2022NK2036)Xiangxi Prefecture Science and Technology Plan Project"School-Local Integration"Special Project(No.2022001)the scientific research project of Hunan Provincial Department of Education(No.22B0520).
文摘Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in China.In vine tea processing,a large amount of broken tea is produced,which has low commercial value.Methods:This study investigates the influence of different extraction methods(room temperature water extraction,boiling water extraction,ultrasonic-assisted room temperature water extraction,and ultrasonic-assisted boiling water extraction,referred to as room temperature water extraction(RE),boiling water extraction(BE),ultrasonic assistance at room temperature water extraction(URE),and ultrasonic assistance in boiling water extraction(UBE))on the yield,dihydromyricetin(DMY)content,free amino acid composition,volatile aroma components,and antioxidant properties of vine tea extracts.Results:A notable influence of extraction temperature on the yield of vine tea extracts(P<0.05),with BE yielding the highest at 43.13±0.26%,higher than that of RE(34.29±0.81%).Ultrasound-assisted extraction significantly increased the DMY content of the extracts(P<0.05),whereas DMY content in the RE extracts was 59.94±1.70%,that of URE reached 66.14±2.78%.Analysis revealed 17 amino acids,with L-serine and aspartic acid being the most abundant in the extracts,nevertheless ultrasound-assisted extraction reduced total free amino acid content.Gas chromatography-mass spectrometry analysis demonstrated an increase in the diversity and quantity of compounds in the vine tea water extracts obtained through ultrasonic-assisted extraction.Specifically,69 and 68 volatile compounds were found in URE and UBE extracts,which were higher than the number found in RE and BE extracts.In vitro,antioxidant activity assessments revealed varying antioxidant capacities among different extraction methods,with RE exhibiting the highest DPPH scavenging rate,URE leading in ABTS•+free radical scavenging,and BE demonstrating superior ferric ion reducing antioxidant activity.Conclusion:The findings suggest that extraction methods significantly influence the chemical composition and antioxidant properties of vine tea extracts.Ultrasonic-assisted extraction proved instrumental in elevating the DMY content in vine tea extracts,thereby enriching its flavor profile while maintaining its antioxidant properties.
基金National Natural Science Foundation of China(No.61201412)Ntural Science Foundation of Shanxi Province(No.2012021011-5)
文摘Phase aberration correction for medical ultrasound systems has attracted a great deal of attention. Since phased array techniques are now widely employed for industrial non-destructive testing (NDT) applications in various fields, the problem of phase aberrations in the process of NDT testing is considered. The technique of cross-covariance for phase aberration correction is presented. The performance of the technique for phase aberration correction is tested by means of echo signals obtained in practical non-destructive testing experiment. The results show that the technique has the better accuracy of phase correction.
基金Ministry of Higher Education of Malaysia for funding the project on PEC NDT at IIUM through the research grant FRGS16-059-0558supported by the National Natural Science Foundation of China under research grants 51677187 and 51307172
文摘Pulsed eddy current (PEC) non-destructive test- ing and evaluation (NDT&E) has been around for some time and it is still attracting extensive attention from researchers around the globe, which can be witnessed through the reports reviewed in this paper. Thanks to its richness of spectral components, various applications of this technique have been proposed and reported in the lit- erature covering both structural integrity inspection and material characterization in various industrial sectors. To support its development and for better understanding of the phenomena around the transient induced eddy currents, attempts for its modelling both analytically and numeri- cally have been made by researchers around the world. This review is an attempt to capture the state-of-the-art development and applications of PEC, especially in the last 15 years and it is not intended to be exhaustive. Future challenges and opportunities for PEC NDT&E are also presented.
文摘In recent years, advanced composite structures are used extensively in many industries such as aerospace, aircraft, automobile, pipeline and civil engineering. Reliability and safety are crucial requirements posed by them to the advanced composite structures be- cause of their harsh working conditions. Therefore, as a very important measure, structural health monitoring (SHM) in-service is deft- nitely demanded for ensuring their safe working in-situ. In this paper, fiber Bragg grating (FBG) sensors are surface-mounted on the hoop and in the axial directions of a FRP pressure vessel to monitor the strain status during its pressurization. The experimental results show that the FBG sensors could be used to monitor the strain development and determine the ultimate failure strain of the composite pressure vessel.
基金National Key Research and Development Project of China(No.2018YFB1701200)。
文摘Aiming at the problems of low reliability and complex operation of traditional coin-tap test of composite material,this paper introduces the grey system theory and achieves better performance.The response signals of coin-tap are classified through the grey clustering based on relation analysis,and corresponding improvements are made to the calculation method of the relation degree of nearness.First,the time history of acceleration is taken as the system behavior sequence.The improved correlation calculation method is used to solve the relation degree of nearness between the sequences,and the matrix of degree of grey relation is constructed based on this.Then,the sequence groups are summarized through the matrix,and the response signals of coin-tap are qualitatively classified according to the location of the reference sequence.Finally,the defect detection of composite materials is completed without pre-testing.The test results show that the accuracy of the coin-tap test based on improved grey clustering reaches 100%,which simplifies the operation steps while ensuring the reliability of the coin-tap test results.
文摘Non-destructive testing (NDT) of structures is one of the most important tasksof the proper maintenance and diagnosis of machines and constructions structuralcondition. NDT methods contribute to the damage tolerance philosophy used in theaircraft design methodology as well as many other operation and maintenance programsof machinery and constructions. The following study is focusing on overviewing animportant group of NDT methods: the optical and other ones, which found broadapplicability in scientific and industrial studies nowadays. The paper discusses theselected most widely applicable methods, namely, visual testing, ultrasonic testing,radiographic testing, infrared thermography as well as electronic speckle patterninterferometry and shearographic testing. Besides the basic principles of testing usingthese methods, their potential applications in various industrial and technologicalbranches are broadly discussed. The analysis as categorization of the NDT methodsprovided in this paper may help in selection of such methods in diagnosis of varioustypes of structures and defects and damage occurring in these structures.
基金supported by the Center for Innovative Grouting Materials and Technology (CIGMAT) at the University of Houston, Texas, USA
文摘The characterization of ultra-soft clayey soil exhibits extreme challenges due to low shear strength of such material.Hence,inspecting the non-destructive electrical impedance behavior of untreated and treated ultra-soft clayey soils gains more attention.Both shear strength and electrical impedance were measured experimentally for both untreated and treated ultra-soft clayey soils.The shear strength of untreated ultra-soft clayey soil reached 0.17 kPa for 10% bentonite content,while the shear strengths increased to 0.27 kPa and 6.7 kPa for 10% bentonite content treated with 2% lime and 10% polymer,respectively.The electrical impedance of the ultra-soft clayey soil has shown a significant decrease from 1.6 kΩ to 0.607 kΩ when the bentonite content increased from 2% to 10% at a frequency of 300 kHz.The10%lime and 10% polymer treatments have decreased the electrical impedances of ultra-soft clayey soil with 10%bentonite from 0.607 kΩ to 0.12 kΩ and 0.176 kΩ,respectively,at a frequency of 300 kHz.A new mathematical model has been accordingly proposed to model the non-destructive electrical impedancefrequency relationship for both untreated and treated ultra-soft clayey soils.The new model has shown a good agreement with experimental data with coefficient of determination(R;)up to 0.99 and root mean square error(RMSE) of 0.007 kΩ.
基金supported by the scientific and technological key project in Henan Province (No.212102210148)Open fund of Key Laboratory of Grain Information Processing and Control (No.KFJJ-2018-101)
文摘Wheat quality detection is essential to ensure the safety ofwheat circulation and storage.The traditional wheat quality detection methods mainly include artificial sensory evaluation and physicochemical index analysis,which are difficult to meet the requirements for high accuracy and efficiency in modern wheat quality detection due to the disadvantages of subjectivity,destruction of sample integrity and low efficiency.With the rapid development of optical technology,various optical-based methods,using near-infrared spectroscopy technology,hyperspectral imaging technology and terahertz,etc.,have been proposed for wheat quality detection.These methods have the characteristics of nondestructiveness and high efficiency which make them popular in wheat quality detection in recent years.In this paper,various state-of-the-art optical-based techniques of wheat quality detection are analyzed and summarized in detail.Firstly,the principle and process of common optical non-destructive detection methods for wheat quality are introduced.Then,the optical techniques used in these detection methods are divided into seven categories,and the comparison of these technologies and their advantages and disadvantages are further discussed.It shows that terahertz technology is regarded as the most promising wheat quality detection method compared with other optical detection technologies,because it can not only detect most types of wheat deterioration,but also has higher accuracy and efficiency.Finally,the research of optical technology in wheat quality detection is prospected.The future research of optical technology-based wheat quality detection mainly includes the construction of wheat quality optical detection standardization database,the fusion of multiple optical detection technologies and multiple quality index information,the improvement of the anti-interference of optical technology and the industrialization of optical inspection technology for wheat quality.These studies are of great significance to improve the detection technology of wheat and ensure the storage safety of wheat in the future.
文摘Accurate assessment of herbage mass (HM) in pasture is a key to budgeting forage in grazing systems worldwide. Different non-destructive techniques to measuring pasture yield are commented. The methods compared include visual estimations, manual and electronic pasture meters and remote sensing. All methods are associated with a moderate to high error, showing that some indirect methods of yield estimation are appropriate under most appropriate because many factors as climate variations, soil certain conditions. In general terms, no method was found as the characteristics, plant phenology, pasture management and species composition must be taken into account to make local calibrations from a general model. Best results were found modifying general methods under local calibrations and under local conditions. In order to give farmers the best method to manage adequately their own grazing systems, researchers must select the most suitable technique considering the scale of operation, the desired accuracy and the resources available.
基金supported by the Cooperative Innovation Center of Terahertz Science , the National Basic Research Program of China (Grant No. 2014CB339800)the National Natural Science Foundation of China (Grant Nos. 61138001, 61420106006)+1 种基金the Program for Changjiang Scholars and Innovative Research Team in University (grant No. IRT13033)the Major National Development Project of Scientific Instruments and Equipment of China (Grant No. 2011YQ150021)
文摘Optoelectronic terahertz generation and detection play a key role in the applications of non-destructive testing,which involves different areas such as physics,biological,material science,imaging,explosions detection,astronomy applications,semiconductor technology and superconductiong electronics. In this article,we present a reviewof the principle and performance of typical terahertz sources,detectors and non-destructive testing applications. On this basis,the newdevelopment and trends of terahertz radiation detectors are also discussed.
文摘In this study, water permeation through cementitious materials was observed using magnetic resonance imaging (MRI). The influence of cement type on the magnetic resonance signal was studied subsequent to determining the parameters required for imaging. Consequently, adequate imaging of water permeating through hardened cement paste (HCP) made with white Portland cement was achieved, while water permeation through ordinary Portland cement-based HCP yielded poor signal. HCPs maintained at various levels of relative humidity (RH) were observed, and the signal was detected only from those maintained at an RH of higher than 85%. The water permeation depths in HCP were observed by using MRI, and the measured depths were compared to those measured via a spraying water detector on the split surface of the specimens. As a result, good agreement was confirmed between the two methods. Additionally, MRI was applied to concrete specimens;although it was found that water was not detected when a lightweight aggregate was used, water permeation through concrete with limestone aggregate was detectable via MRI. MRI will help in understanding how water permeation causes and accelerates concrete deteriorations such as rebar corrosion and freezing and thawing.
基金Supported by the Natural Science Foundation of Guangdong Province(2017A030310558)China Postdoctoral Science Foundation(2017M612672)Fundamental Research Funds for the Central Universities(2017MS067)
文摘This study was undertaken to investigate the feasibility of near-infrared(NIR) hyperspectral imaging(1 000–2 500 nm) for non-destructive and quantitative prediction of protein content in peanut kernels. Partial least squares regression(PLSR) calibration model was established between the spectral data extracted from the hyperspectral images and the reference measured protein content values, with the coefficient of determination of prediction(R_P^2) of 0.885 and root mean square error of prediction(RMSEP) of 0.465%.Regression coefficients(RC) from PLSR analysis were used to identify the most essential wavelengths that had the greatest influence on changes in the protein content. Eight optimal wavelengths were selected by RC and its corresponding simplified RC-PLSR prediction model was also obtained, showing better performance with a higher R_P^2 of 0.870 and a lower RMSEP of 0.494%. The results indicate that hyperspectral imaging with PLSR analysis can be used as a rapid and non-destructive method for predicting protein content in peanut.
基金Supported by the 863 National High Technology Research and Development Program(No.2012AA121901)
文摘Ground Penetrating Radar(GPR) is an effective Non-Destructive Testing(NDT) technique for highway pavement surveys, which is able to acquire continuous pavement data compared with traditional core drilling method. In this study, we proposed an accurate and efficient method to estimate the thickness of each pavement layer using an air-coupled GPR system. For this work, the main difficulties are estimating each pavement layer's time delay and dielectric constant. We first give the basic signal model for pavement evaluation, and then present an Intrinsic Mode Functions(IMFs) product detector to determine each pavement layer's time delay. This method is based on Empirical Mode Decomposition(EMD), which is an adaptive signal decomposition procedure and proved to be suitable for suppressing noises in GPR signal. The dielectric constant was determined by metal reflection measurement. The laboratory and highway experiments illustrate that the proposed thickness estimation method yields reasonable result, thus meets the requirements of practical highway pavement survey with massive GPR data.
基金Sichuan province Science and Technology department( No. 2011GZ0002 and No. 2013HH0059)the university basic scientific research project( No. ZYGX2013J090 ) for funding the work
文摘This paper introduces recent research work in the field of pulsed electromagnetic non-destructive testing/evaluation.These are pulsed eddy current,pulsed magnetic flux leakage and eddy current pulsed thermography.This paper introduces pulsed electromagnetic techniques and their different case studies on defect detection as well as stress characterisation.Experimental tests have been validated and future research plans are discussed.This paper demonstrates pulsed electromagnetic non-destructive testing and evaluation for not only depth information,but also for multiple parameter measurement and multiple integration,which are important for future development.
基金funded by the National Key Research and Development Program of China(2022YFA1304201)the Beijing Natural Science Foundation(6222032)+2 种基金the Starting Grants Program for Young Talents at China Agricultural Universitythe 2115 Talent Development Program of China Agricultural UniversityChinese Universities Scientific Fund。
文摘Background Ginkgo biloba extract(GBE)is evidenced to be effective in the prevention and alleviation of metabolic disorders,including obesity,diabetes and fatty liver disease.However,the role of GBE in alleviating fatty liver hemorrhagic syndrome(FLHS)in laying hens and the underlying mechanisms remain to be elucidated.Here,we investigated the effects of GBE on relieving FLHS with an emphasis on the modulatory role of GBE in chicken gut microbiota.Results The results showed that GBE treatment ameliorated biochemical blood indicators in high-fat diet(HFD)-induced FLHS laying hen model by decreasing the levels of TG,TC,ALT and ALP.The lipid accumulation and pathological score of liver were also relieved after GBE treatment.Moreover,GBE treatment enhanced the antioxidant activity of liver and serum by increasing GSH,SOD,T-AOC,GSH-PX and reducing MDA,and downregulated the expression of genes related to lipid synthesis(FAS,LXRα,GPAT1,PPARγand Ch REBP1)and inflammatory cytokines(TNF-α,IL-6,TLR4 and NF-κB)in the liver.Microbial profiling analysis revealed that GBE treatment reshaped the HFD-perturbed gut microbiota,particularly elevated the abundance of Megasphaera in the cecum.Meanwhile,targeted metabolomic analysis of SCFAs revealed that GBE treatment significantly promoted the production of total SCFAs,acetate and propionate,which were positively correlated with the GBE-enriched gut microbiota.Finally,we confirmed that the GBE-altered gut microbiota was sufficient to alleviate FLHS by fecal microbiota transplantation(FMT).Conclusions We provided evidence that GBE alleviated FLHS in HFD-induced laying hens through reshaping the composition of gut microbiota.Our findings shed light on mechanism underlying the anti-FLHS efficacy of GBE and lay foundations for future use of GBE as additive to prevent and control FLHS in laying hen industry.
基金Project supported by the National Natural Science Foundation of China (No 10404026) and the Specialized Research Fund for the Doctoral Program of Higher Education (No 20020358008).
文摘In this paper single ultra-fast voltage pulses are introduced to the Pt/Ir tip of a scanning tunnelling microscope (STM), and the non-destructive threshold of the graphite surface is studied systematically in a wide range of pulse durations (from 104 to 8 ns). Considering the waveform distortion of the pulses at the tunnelling region, this paper gives the corrected threshold curve of pulse amplitude depending on pulse duration. A new explanation of threshold power has been suggested and fits the experimental results well.
基金financially supported by the National Key Research and Development Program of China(2021YFD2100904)the National Natural Science Foundation of China(31871729,32172147)+2 种基金the Modern Agriculture key Project of Jiangsu Province of China(BE2022317)the Modern Agricultural Industrial Technology System Construction Project of Jiangsu Province of China(JATS[2021]522)a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinations is more significant than a specific food component.This study investigated the lipid-lowering effect of highland barley polyphenols via lipase assay in vitro and HepG2 cells induced by oleic acid(OA).Five indexes,triglyceride(TG),total cholesterol(T-CHO),low density lipoprotein-cholesterol(LDL-C),aspartate aminotransferase(AST),and alanine aminotransferase(ALT),were used to evaluate the lipidlowering effect of highland barley extract.We also preliminary studied the lipid-lowering mechanism by Realtime fluorescent quantitative polymerase chain reaction(q PCR).The results indicated that highland barley extract contains many components with lipid-lowering effects,such as hyperoside and scoparone.In vitro,the lipase assay showed an 18.4%lipase inhibition rate when the additive contents of highland barley extract were 100μg/m L.The intracellular lipid-lowering effect of highland barley extract was examined using 0.25 mmol/L OA-induced HepG2 cells.The results showed that intracellular TG,LDL-C,and T-CHO content decreased by 34.4%,51.2%,and 18.4%,respectively.ALT and AST decreased by 51.6%and 20.7%compared with the untreated hyperlipidemic HepG2 cells.q PCR results showed that highland barley polyphenols could up-regulation the expression of lipid metabolism-related genes such as PPARγand Fabp4.