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In situ non-destructive measurement of Josephson junction resistance using fritting contact technique
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作者 Lei Du Hao-Ran Tao +7 位作者 Liang-Liang Guo Hai-Feng Zhang Yong Chen Xin Tian Chi Zhang Zhi-Long Jia Peng Duan Guo-Ping Guo 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期57-61,共5页
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
关键词 non-destructive fritting contact qubit frequency Josephson junction resistance
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Flexible pavement longitudinal joint quality evaluation using non-destructive testing
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作者 Hamad Bin Muslim Syed Waqar Haider Lev Khazanovich 《Journal of Road Engineering》 2024年第2期189-202,共14页
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
关键词 Sustainable pavements Dielectric/density profiling system Quality assurance non-destructive testing Asphalt longitudinal joint
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Acoustic Non-Destructive Testing Technology in Concrete Bridge Inspection and Pile Foundation Detection
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作者 Wei Fu 《Journal of Architectural Research and Development》 2024年第1期20-25,共6页
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
关键词 Concrete bridge Bridge detection Acoustic detection non-destructive testing technology
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Phase aberration correction in ultrasonic phased array non-destructive testing systems
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作者 赵霞 王召巴 刘宾 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第1期47-52,共6页
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
关键词 ultrasonic phased array non-destructive testing phase aberration CORRECTION cross-covariance method
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Pulsed Eddy Current Non-destructive Testing and Evaluation:A Review 被引量:31
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作者 Ali Sophian Guiyun Tian Mengbao Fan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第3期500-514,共15页
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
关键词 non-destructive testing - Pulsed eddy currentsMaterial characterization Structural integrity non-destructive evaluation
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Portable System for CWA Detection Using Micro Array Gas Sensor 被引量:4
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作者 J.H.Kwak Y.T.Lim +6 位作者 G.H.Kim N.J.Choi H.D.Park G.H.Rue J.S.Huh J.C.Kim D.D.Lee 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期124-128,共5页
Biochemistry weapon is raising new tools of war and terror.This research is an experiment about portable system for CWAs (chemical warfare agents) detection using micro array gas system.CWAs were divided into four typ... Biochemistry weapon is raising new tools of war and terror.This research is an experiment about portable system for CWAs (chemical warfare agents) detection using micro array gas system.CWAs were divided into four types such as blood, nerve,vesicant,and choking agent.To detect various CWAs,semiconductor thick film sensor array based on tin oxide was fabricated and their gas responses were examined.Operating temperature was range of 250℃to 350℃and gas concentration was range of 0.1μg/g to 10μg/g.Sensor array was measured as operating temperatures,concentrations for four simulant agents of CWAs.Extracted parameters from results were carried out classification among CWAs through the principal component analysis (PCA).Also,classification of gases is studied using adaptive resonance theory (ART) that is one of neural network algorithm.Results displayed using PDA system. 展开更多
关键词 SNO2 chemical warfare agents(CWAs) portable system ART ARRAY PCA
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An Information Hiding Algorithm Based on Bitmap Resource of Portable Executable File 被引量:2
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作者 Jie Xu Li-Jun Feng Ya-Lan Ye Yue Wu 《Journal of Electronic Science and Technology》 CAS 2012年第2期181-184,共4页
An information hiding algorithm is proposed, which hides information by embedding secret data into the palette of bitmap resources of portable executable (PE) files. This algorithm has higher security than some trad... An information hiding algorithm is proposed, which hides information by embedding secret data into the palette of bitmap resources of portable executable (PE) files. This algorithm has higher security than some traditional ones because of integrating secret data and bitmap resources together. Through analyzing the principle of bitmap resources parsing in an operating system and the layer of resource data in PE files, a safe and useful solution is presented to solve two problems that bitmap resources are incorrectly analyzed and other resources data are confused in the process of data embedding. The feasibility and effectiveness of the proposed algorithm are confirmed through computer experiments. 展开更多
关键词 Bitmap resources data embedding information hiding portable executable file.
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Portable mixed abrasive water jet equipment for rescue in high gas mine shaft 被引量:7
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作者 ZENG Rui DU Chang-long +1 位作者 XU Rui ZHAO Jing 《Journal of Coal Science & Engineering(China)》 2011年第2期207-211,共5页
In order to rescue a trapped miner and clean out roadways quickly in a high gas mine shaft after a mining mishap, a special portable cold-cutting equipment is needed, the main technology parameters were calculated acc... In order to rescue a trapped miner and clean out roadways quickly in a high gas mine shaft after a mining mishap, a special portable cold-cutting equipment is needed, the main technology parameters were calculated according to the advanced cold-cutting technology of high pressure abrasive water jet and the portable mixed abrasive water jet equipment (PAWE) was designed to meet the needs of emergency rescue in high gas mine shafts. Tested the PAWE in a high gas environment, and the result shows that the maximum cutting depth of solid iron pipe is 18 mm and the recoilforce of the sprayer is 28.9 N under the conditions that actual cutting pressure is 29 MPa, starting target distance is 10 ram, cutting speed is 180 mm/min and concentration of abrasive is 32%. The course of the experiment in the high gas environment was smooth and continuous, without any explosion. The PAWE is easy to move and operate, but the nozzle which was worn badly in the sprayer should be changed every 8 minutes. 展开更多
关键词 portable ABRASIVE water jet emergency rescue GAS
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Non-destructive Evaluation of Composite Pressure Vessel by Using FBG Sensors 被引量:5
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作者 HAO Jun-cai LENG Jin-song WEI Zhang 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2007年第2期120-123,共4页
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
关键词 fiber optic sensor fiber Bragg grating composite pressure vessel non-destructive evaluation
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Use of portable X-ray fluorescence in the analysis of surficial sediments in the exploration of hydrothermal vents on the Southwest Indian Ridge 被引量:5
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作者 LIAO Shili TAO Chunhui +3 位作者 LI Huaiming ZHANG Guoyin LIANG Jin YANG Weifang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第7期66-76,共11页
Hydrothermal plumes released from the eruption of sea floor hydrothermal fluids contain large amounts of oreforming materials. They precipitate within certain distances from the hydrothermal vent. Six surficial sedime... Hydrothermal plumes released from the eruption of sea floor hydrothermal fluids contain large amounts of oreforming materials. They precipitate within certain distances from the hydrothermal vent. Six surficial sediment samples from the Southwest Indian Ridge(SWIR) were analyzed by a portable X-ray fluorescence(PXRF) analyzer on board to find a favorable method fast and efficient enough for sea floor sulfide sediment geochemical exploration. These sediments were sampled near, at a moderate distance from, or far away from hydrothermal vents. The results demonstrate that the PXRF is effective in determining the enrichment characteristics of the oreforming elements in the calcareous sediments from the mid-ocean ridge. Sediment samples(〉40 mesh) have high levels of elemental copper, zinc, iron, and manganese, and levels of these elements in sediments finer than 40 mesh are lower and relatively stable. This may be due to relatively high levels of basalt debris/glass in the coarse sediments, which are consistent with the results obtained by microscopic observation. The results also show clear zoning of elements copper, zinc, arsenic, iron, and manganese in the surficial sediments around the hydrothermal vent. Sediments near the vent show relatively high content of the ore-forming elements and either high ratios of copper to iron content and zinc to iron content or high ratios of copper to manganese content and zinc to manganese content. These findings show that the content of the ore-forming elements in the sediments around hydrothermal vents are mainly influenced by the distance of sediments to the vent, rather than grain size. In this way, the PXRF analysis of surface sediment geochemistry is found to satisfy the requirements of recognition geochemical anomaly in mid-ocean ridge sediments. Sediments with diameters finer than 40 mesh should be used as analytical samples in the geochemical exploration for hydrothermal vents on mid-oceanic ridges. The results concerning copper, zinc, arsenic, iron, and manganese and their ratio features can be used as indicators in sediment geochemical exploration of seafloor sulfides. 展开更多
关键词 mid-ocean ridge sediments hydrothermal activity portable X-ray fluorescence geochemical exploration
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Collecting Traffic Video Data Using Portable Poles: Survey, Proposal, and Analysis 被引量:2
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作者 Morten B. Jensen Chris H. Bahnsen +2 位作者 Harry S. Lahrmann Tanja K. O. Madsen Thomas B. Moeslund 《Journal of Transportation Technologies》 2018年第4期376-400,共25页
Several initiatives have been launched to help prevention of traffic accidents and near-accidents across the European Union. To aid the overall goal of reducing deaths and injuries related to traffic, one must underst... Several initiatives have been launched to help prevention of traffic accidents and near-accidents across the European Union. To aid the overall goal of reducing deaths and injuries related to traffic, one must understand the causation of the traffic accidents in order to prevent them. Rather than deploying a person to physically monitor a location, the task is eased by camera equipment installed in existing infrastructure, e.g. poles, and buildings, etc. In rural areas there is however a very limited infrastructure available which complicates the data acquisition. But even if there is infrastructure available in either the rural area or the urban area, this might not serve as an ideal position to capture video data from. In this work, we survey and provide an overview of available and relevant portable poles setups with respect to capturing data in both urban areas and rural areas. The conclusion of the survey shows a lack of a mobile, lightweight, compact, and easy deployable portable pole. We therefore design and develop a new portable pole meeting these requirements. The new proposed portable pole can be deployed by 2 persons in 2 hours in both rural areas as well as urban areas due to its compactness. The deployment and usage of the new portable pole is a complimentary tool, which may improve the camera capturing angle in case existing infrastructure is insufficient. This ultimately improves the traffic monitoring opportunities. Further, the survey of selected portable poles provides an excellent overview and can aid multiple applications within road traffic. 展开更多
关键词 Road TRAFFIC Video ANALYSIS Camera MOUNTING Pole portable
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Occlusion of the middle cerebral artery Guidance by screen imaging using an EDA-H portable medium-soft electronic endoscope 被引量:1
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作者 Xingbao Zhu Junli Luo +3 位作者 Song Liu Dongping Li Min Li Quanshui Fan 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第23期1806-1809,共4页
The present study aimed to verify the practicability of performing screen-based surgical operations under the guidance of a real-time viewing and recording system (RTVRS) using a portable medium-soft electronic endo... The present study aimed to verify the practicability of performing screen-based surgical operations under the guidance of a real-time viewing and recording system (RTVRS) using a portable medium-soft electronic endoscope (pmsEE). The middle cerebral artery in rats was occluded under screen-imaging guidance using a pmsEE RTVRS to reproduce an animal model of human cerebral infarction. The screen imaging of the pmsEE RTVRS was clear, life-like, stereoscopic and synchronous with the actual operation. Screen-imaging guidance led to an accurate, smooth, minimally invasive and comparatively easy surgical procedure. The surgical success rate, time of model establishment, neurological function scores, and infarct volume were similar to those using an operating microscope. These results indicate that the self-designed pmsEE RTVRS could be utilized for portable endoscopic screen-based surgical operations. 展开更多
关键词 portable medium-soft endoscope screen-based surgical operation occlusion of middle cerebral artery cerebral infarction
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Localization of a Robotic Capsule for GI Motility Inspection with a Portable Ultrasonic System 被引量:3
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作者 姜萍萍 颜国正 《Journal of Donghua University(English Edition)》 EI CAS 2004年第3期190-194,共5页
The micro-systems used for in vivo physical inspection have many advantages over traditional methods. In order to aid diagnosis of gastrointestinal (GI) motility disorders, a capsule is developed for GI pressure and p... The micro-systems used for in vivo physical inspection have many advantages over traditional methods. In order to aid diagnosis of gastrointestinal (GI) motility disorders, a capsule is developed for GI pressure and pH inspection. Localization of the capsule in GI tract with time is a necessary condition for subsequent data analysis and medical diagnosis. It is also a common problem facing all in vivo mobile micro-systems. An approach of segment localization by utilizing some key points along GI tract is proposed. A portable ultrasonic detecting device was designed for this purpose. Experiments under conditions similar to GI tract were carried out and the results proved the effectiveness and reliability of this method and the device. 展开更多
关键词 robotic capsule GI motility inspection portable ultrasonic system
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Automatic Measurement of Fetal Abdominal Biometric Parameters—Feasibility on a Portable Ultrasound Device 被引量:1
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作者 Naiad Hossain Khan Eva Tegnander +4 位作者 Sigurd Storve Johan Morten Dreier Sturla Eik-Nes Hans Torp Gabriel Kiss 《Open Journal of Obstetrics and Gynecology》 2017年第8期922-936,共15页
An automatic method for measuring the fetal mean abdominal diameter (MAD) or abdominal circumference (AC) with ultrasound is proposed. From a correctly presented abdominal section suitable for MAD or AC measurement, t... An automatic method for measuring the fetal mean abdominal diameter (MAD) or abdominal circumference (AC) with ultrasound is proposed. From a correctly presented abdominal section suitable for MAD or AC measurement, the location of fetal abdomen is detected by image processing. Thereafter, an active contour model is converged along the abdominal boundary for measurement purposes. The validation data set contained 310 images of fetuses with gestational age (GA) from 14 to 41 weeks. The measurement success rate was 88.1%. By manually indicating the location of the abdomen, the success rate was further improved to 95.8% for the failed cases. The correlation between manual and automatic measurements was 0.95 and the intraclass correlation coefficient (ICC) was 0.976 (95% confidence interval (CI);0.969 - 0.981). The average method execution time was 0.3 s. The mean error was lower in young fetuses (0.4%) than in older fetuses (-2.1%). The proposed cross-platform method was implemented on a portable, low-cost ultrasound machine prototype targeted for low- and middle-income countries (LMIC);the results achieved were comparable to those of other state-of-the-art automatic methods. 展开更多
关键词 portable ULTRASOUND Scanner AUTOMATIC Measurement Mean ABDOMINAL Diameter ABDOMINAL CIRCUMFERENCE PRENATAL ULTRASOUND ICT4D
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A coin-tap method of composite materials non-destructive testing based on improved grey clustering 被引量:2
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作者 YU Xiaowen XU Liping +1 位作者 LI Jian WANG Wei 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2021年第1期120-126,共7页
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
关键词 non-destructive testing coin-tap test grey clustering based on relation analysis composite material
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Non-Destructive Testing of Structures Using Optical and Other Methods: A Review 被引量:1
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作者 A.Kroworz A.Katunin 《Structural Durability & Health Monitoring》 EI 2018年第1期1-17,共17页
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
关键词 non-destructive testing optical NDT methods testing of structures damageidentification
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Portable and automated analyzer for rapid and high precision in vitro dissolution of drugs 被引量:1
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作者 Zhongmei Chi Siqi Zhao +2 位作者 Xiujun Cui Yunxiang Feng Li Yang 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2021年第4期490-498,共9页
We developed a novel portable and automated dissolution test analyzer for rapid and high precision in vitro dissolution testing of drugs.The analyzer consists of a flow-through-cell drug dissolution system,an automate... We developed a novel portable and automated dissolution test analyzer for rapid and high precision in vitro dissolution testing of drugs.The analyzer consists of a flow-through-cell drug dissolution system,an automated sequential sampling system,a high-speed capillary electrophoresis(HSCE)system,and a data acquisition system.Combining the high-temporal resolution flow-gating sampling approach with HSCE,which has outstanding advantages of efficient separation and resolution,the analyzer can achieve rapid analysis and exhibits the ability in miniaturization for on-site assessment of different active pharmaceutical ingredients.To integrate the flow-through-cell dissolution system with HSCE,a specially designed flow-gating-injection(FGI)interface was employed.The performance of the analyzer was investigated by analyzing the dissolution of immediate-release drugs including single dose(amoxicillin dispersible tablets)and fixed dose combination(amoxicillin and clavulanate potassium)drug tablets with the high-temporal resolutions of 12 s and 20 s,respectively.The dissolution profiles of different active pharmaceutical ingredients could be simultaneously and automatically monitored with high repeatability and accuracy.The analyzer was successfully utilized for the pharmaceutical quality control and bio-relevant dissolution testing,as well as in vivo-in vitro correlation analysis.Our portable analyzer is miniaturized,convenient and of low-cost,and will provide a valuable tool for dissolution testing in pharmaceutical research and development. 展开更多
关键词 Dissolution test analyzer portable AUTOMATED Immediate-release drug Fixed dose combination drug
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Non-destructive experimental testing and modeling of electrical impedance behavior of untreated and treated ultra-soft clayey soils 被引量:1
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作者 Aram M.Raheem Cumaraswamy Vipulanandan Mohammad S. Joshaghani 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2017年第3期161-168,共8页
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
关键词 Ultra-soft clayey soil BENTONITE LIME Polymer Shear strength non-destructive testing Electrical impedance
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RESEARCH OF A NEW PORTABLE GC INSTRUMENTATION AND ITS APPLICATION IN BIOMEDICAL ENGINEERING 被引量:3
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作者 Li Fucheng Li Zhiyi Pan Qi (College of Precision Instrumentation and photoelectron Engineering Tianjin University, Tianjin, 300072, China) 《Chinese Journal of Biomedical Engineering(English Edition)》 1997年第4期243-248,共6页
-A Portable gas chromatograPhy (GC) instrument is presented in this paper. In this GC instrument a new gaseous sampling device was used in place of conventional sampling valves.It has no quantitative tube or movable c... -A Portable gas chromatograPhy (GC) instrument is presented in this paper. In this GC instrument a new gaseous sampling device was used in place of conventional sampling valves.It has no quantitative tube or movable components in the sample Path. The sampling size si determined by time with a high precision,which is not sensitive to the sample temperature and pressure.Especially,the sample can not only inject into the column head,but also the carrier gas blow the column reversely and clean it.The portable GC instrument based on the sampling device can be used in enviromental and biomedical monitoring. 展开更多
关键词 GAS Chromatograpky Sampling DEVICE portable instrument.
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Real-Time Black Carbon Emissions from Light-Duty Passenger Vehicles Using a Portable Emissions Measurement System 被引量:1
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作者 Xuan Zheng Liqiang He +4 位作者 Xiaoyi He Shaojun Zhang Yihuan Cao Jiming Hao Ye Wu 《Engineering》 SCIE EI CAS 2022年第9期73-81,共9页
Black carbon(BC)is considered the second largest anthropogenic climate forcer,but the radiative effects of BC are highly correlated with its combustion sources.On-road vehicles are an important source of anthropogenic... Black carbon(BC)is considered the second largest anthropogenic climate forcer,but the radiative effects of BC are highly correlated with its combustion sources.On-road vehicles are an important source of anthropogenic BC.However,there are major uncertainties in the estimates of the BC emissions from on-road light-duty passenger vehicles(LDPVs),and results obtained with the portable emissions measurement system(PEMS)method are particularly lacking.We developed a PEMS platform and evaluated the on-road BC emissions from ten in-use LDPVs.We demonstrated that the BC emission factors(EFs)of gasoline direction injection(GDI)engine vehicles range from 1.10 to 1.56 mg.km^(-1),which are higher than the EFs of port fuel injection(PFI)engine vehicles(0.10–0.17 mg.km^(-1))by a factor of 11.The BC emissions during the cold-start phase contributed 2%–33%to the total emissions.A strong correlation(R^(2)=0.70)was observed between the relative BC EFs and average vehicle speed,indicating that traffic congestion alleviation could effectively mitigate BC emissions.Moreover,BC and particle number(PN)emissions were linearly correlated(R^(2)=0.90),and compared to PFI engine vehicles,the instantaneous PN-to-BC emission rates of GDI engine vehicles were less sensitive to vehicle specific power-to-velocity(VSPV)increase in all speed ranges. 展开更多
关键词 Black carbon Light-duty gasoline vehicles portable emissions measurement system Real-time emissions
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