Improvements in imaging technology allow exploitation of the dual blood supply of the liver to aid in the identif ication and characterisation of both malignant and benign liver lesions. Imaging techniques available i...Improvements in imaging technology allow exploitation of the dual blood supply of the liver to aid in the identif ication and characterisation of both malignant and benign liver lesions. Imaging techniques available include contrast enhanced ultrasound, computed tomography and magnetic resonance imaging. This review discusses the application of several imaging techniques in the diagnosis and staging of both hepatocellular carcinoma and cholangiocarcinoma and outlines certain characteristics of benign liver lesions. The advantages of each imaging technique are highlighted, while underscoring the potential pitfalls and limitations of each imaging modality.展开更多
In order to realize on-line quantitative detection on SF6 and effective control of nlnning state of SF6 high voltage power supply system, a concentrated SF6 quantitative ultrasonic on-line deteetion system has been de...In order to realize on-line quantitative detection on SF6 and effective control of nlnning state of SF6 high voltage power supply system, a concentrated SF6 quantitative ultrasonic on-line deteetion system has been developed based on the actual demand of electric power system consumers. There are four major characteristics in this system. Firstly, the gas of maximum 64 detection points is transferred through the specific air path to the detection devices to he detected and analyzed, thereby the electrical lines and the complicated installation of the collectors can be avoided; secondly, the differential technique is used to shield the influence of environmental factors, which effectively improves the accuracy of the acoustic detection; thirdly, the SF6 coneentration is determined by the speed and phase in the ultrasonic wave trans- mission process, therefore there is no secondary pollution for the purely physical means; finally, the ma- ture embedded technique is applied in this system to improve its intelligence and stability.展开更多
This paper proposes a loop-tube type thermoacoustic heating system without any moving parts based on the thermoacoustic effect. In a thermoacoustic heating system, the supplied sound is converted to heat and the heati...This paper proposes a loop-tube type thermoacoustic heating system without any moving parts based on the thermoacoustic effect. In a thermoacoustic heating system, the supplied sound is converted to heat and the heating point is heated. A thermoacoustic heating system differs from a thermoacoustic cooling system： The location of the reference temperature section at the heat pump is upside down. The authors construct a prototype ofthermoacoustic heating system. The experimental results show that the heating point reaches 100 ~C. It must be emphasized that, using this simple and inexpensive thermoacoustic heating system, noise, waste heat and unused heat are useful as a renewable energy source.展开更多
Detecting/sensing targets underwater has very important applications in environmental study, civil engineering and national security. In this paper, an organic-film based triboelectric nanogenerator （TENG） has been ...Detecting/sensing targets underwater has very important applications in environmental study, civil engineering and national security. In this paper, an organic-film based triboelectric nanogenerator （TENG） has been successfully demonstrated for the first time as a self-powered and high sensitivity acoustic sensor to detect underwater targets at low frequencies around 100 Hz. This innovative, cost-effective, simple-design TENG consists of a thin-film-based Cu electrode and a polytetrafluoroethylene （PTFE） film with nanostructures on its surfaces. On the basis of the coupling effect between triboelectrification and electrostatic induction, the sensor generates electrical output signals in response to incident sound waves. Operating at a resonance frequency of 110 Hz, under an acoustic pressure of 144.2 dBspc, the maximum open-circuit voltage and short-circuit current of the generator can respectively reach 65 V and 32 ~A underwater. The directional dependence pattern has a bi-directional shape with a total response angle of 60~. Its sensitivity is higher than -185 dB in the frequency range from 30 Hz to 200 Hz. The highest sensitivity is -146 dB at resonance frequency. The three-dimensional coordinates of an acoustic source were identified by four TENGs, self-powered active sensors, and the location of the acoustic source was determined with an error about 0.2 m. This study not only expands the application fields of TENGs from the atmosphere to water, but also shows the TENG is a promising acoustic source locator in underwater environments.展开更多
It is important to obtain a considerable quantity of DNA from oligotrophic environments such as a drinking water distribution system(DWDS)to study microbial communities by molecular biotechnology,and DNA yield is alwa...It is important to obtain a considerable quantity of DNA from oligotrophic environments such as a drinking water distribution system(DWDS)to study microbial communities by molecular biotechnology,and DNA yield is always one of the biggest problems when performing metagenomic sequencing on drinking water samples.To obtain as many microbes as possible,ultrasound has been widely used in cell detachment,but studies on the optimal ultrasonic parameters for biofilm in DWDS have rarely been seen.The effects of three ultrasonic parameters,including power,duration,and the number of ultrasound treatments(USTs)on the selected monoculture bacteria(Pelomonas sp.)biofilm were studied first.Then the optimal values of each ultrasonic parameter were initially determined.Based on these values,three levels of each ultrasonic parameter were selected,and then an orthogonal experiment was conducted to further study drinking water biofilm,and finally the optimal ultrasonic parameters for the effective separation of biofilm cells in DWDS were determined.The results showed that the optimal ultrasonic power,duration,and the number of USTs are 13 W,1 min,and 15,respectively.A 20-min interval is needed between two USTs.The present optimal UST,which does not lose DNA quality,can increase the amount of extractable DNA by at least 4.78 times compared to samples without UST.This study provides a pretreatment methodology for extracting more and reliable DNA from biofilm in DWDS,and can better solve the problem of DNA collection in oligotrophic environments.展开更多
基金Supported by SAK is supported by a grant from the Higher Education Funding Council for England (HEFCE)SDTR is funded by grants from the British Medical Research Council (MRC), London, UK+3 种基金the British Engineering, Physics and Science Research Council (EPSRC), Swindon, UKthe Alan Morement Memorial Fund AMMF, Essex, UKBroad Foundation, Los Angeles, USAPfizer Global Research and Development Inc, Sandwich, UK and GlaxoSmithKline, Ware, UK
文摘Improvements in imaging technology allow exploitation of the dual blood supply of the liver to aid in the identif ication and characterisation of both malignant and benign liver lesions. Imaging techniques available include contrast enhanced ultrasound, computed tomography and magnetic resonance imaging. This review discusses the application of several imaging techniques in the diagnosis and staging of both hepatocellular carcinoma and cholangiocarcinoma and outlines certain characteristics of benign liver lesions. The advantages of each imaging technique are highlighted, while underscoring the potential pitfalls and limitations of each imaging modality.
基金Supported by the National Natural Science Foundation of China (No. 10574038)
文摘In order to realize on-line quantitative detection on SF6 and effective control of nlnning state of SF6 high voltage power supply system, a concentrated SF6 quantitative ultrasonic on-line deteetion system has been developed based on the actual demand of electric power system consumers. There are four major characteristics in this system. Firstly, the gas of maximum 64 detection points is transferred through the specific air path to the detection devices to he detected and analyzed, thereby the electrical lines and the complicated installation of the collectors can be avoided; secondly, the differential technique is used to shield the influence of environmental factors, which effectively improves the accuracy of the acoustic detection; thirdly, the SF6 coneentration is determined by the speed and phase in the ultrasonic wave trans- mission process, therefore there is no secondary pollution for the purely physical means; finally, the ma- ture embedded technique is applied in this system to improve its intelligence and stability.
文摘This paper proposes a loop-tube type thermoacoustic heating system without any moving parts based on the thermoacoustic effect. In a thermoacoustic heating system, the supplied sound is converted to heat and the heating point is heated. A thermoacoustic heating system differs from a thermoacoustic cooling system： The location of the reference temperature section at the heat pump is upside down. The authors construct a prototype ofthermoacoustic heating system. The experimental results show that the heating point reaches 100 ~C. It must be emphasized that, using this simple and inexpensive thermoacoustic heating system, noise, waste heat and unused heat are useful as a renewable energy source.
文摘Detecting/sensing targets underwater has very important applications in environmental study, civil engineering and national security. In this paper, an organic-film based triboelectric nanogenerator （TENG） has been successfully demonstrated for the first time as a self-powered and high sensitivity acoustic sensor to detect underwater targets at low frequencies around 100 Hz. This innovative, cost-effective, simple-design TENG consists of a thin-film-based Cu electrode and a polytetrafluoroethylene （PTFE） film with nanostructures on its surfaces. On the basis of the coupling effect between triboelectrification and electrostatic induction, the sensor generates electrical output signals in response to incident sound waves. Operating at a resonance frequency of 110 Hz, under an acoustic pressure of 144.2 dBspc, the maximum open-circuit voltage and short-circuit current of the generator can respectively reach 65 V and 32 ~A underwater. The directional dependence pattern has a bi-directional shape with a total response angle of 60~. Its sensitivity is higher than -185 dB in the frequency range from 30 Hz to 200 Hz. The highest sensitivity is -146 dB at resonance frequency. The three-dimensional coordinates of an acoustic source were identified by four TENGs, self-powered active sensors, and the location of the acoustic source was determined with an error about 0.2 m. This study not only expands the application fields of TENGs from the atmosphere to water, but also shows the TENG is a promising acoustic source locator in underwater environments.
基金Project supported by the Major Science and Technology Program for Water Pollution Control and Treatment(No.2017ZX07201004)the National Natural Science Foundation of China(No.51678520)。
文摘It is important to obtain a considerable quantity of DNA from oligotrophic environments such as a drinking water distribution system(DWDS)to study microbial communities by molecular biotechnology,and DNA yield is always one of the biggest problems when performing metagenomic sequencing on drinking water samples.To obtain as many microbes as possible,ultrasound has been widely used in cell detachment,but studies on the optimal ultrasonic parameters for biofilm in DWDS have rarely been seen.The effects of three ultrasonic parameters,including power,duration,and the number of ultrasound treatments(USTs)on the selected monoculture bacteria(Pelomonas sp.)biofilm were studied first.Then the optimal values of each ultrasonic parameter were initially determined.Based on these values,three levels of each ultrasonic parameter were selected,and then an orthogonal experiment was conducted to further study drinking water biofilm,and finally the optimal ultrasonic parameters for the effective separation of biofilm cells in DWDS were determined.The results showed that the optimal ultrasonic power,duration,and the number of USTs are 13 W,1 min,and 15,respectively.A 20-min interval is needed between two USTs.The present optimal UST,which does not lose DNA quality,can increase the amount of extractable DNA by at least 4.78 times compared to samples without UST.This study provides a pretreatment methodology for extracting more and reliable DNA from biofilm in DWDS,and can better solve the problem of DNA collection in oligotrophic environments.
