In illuminating tissues,a cylindrical diffuser(CD)has an advantage over regular laser sources due to its ability to illuminate a larger volume of the target tissue.This paper presents a co-registered large volume phot...In illuminating tissues,a cylindrical diffuser(CD)has an advantage over regular laser sources due to its ability to illuminate a larger volume of the target tissue.This paper presents a co-registered large volume photoacoustic(PA)and ultrasonic(US)imaging for early endometrial cancer(EEC)detection using CD.It has the advantage that the US imaging system is outside the body and only the PA excitation device is inside the body,which makes the system more efficient and less invasive for EEC detection.The paper reports on two sets of experiments.Thefirst set produced real-time PA images of blood vessel phantom.The second set demonstrated the imaging of pig uterus ex vivo.The results show that the system has the potential for imaging and characterizing of EEC.展开更多
Measurement of light distribution in biological tissue contributes to selecting strategy and optimizing dose for biomedical application. In this letter, a photoacoustic method combined with Monte Carlo simulation was ...Measurement of light distribution in biological tissue contributes to selecting strategy and optimizing dose for biomedical application. In this letter, a photoacoustic method combined with Monte Carlo simulation was used to estimate the three-dimensional light distribution in biological tissue. The light distribution was produced by a cylindrical diffuser which interposed into tissues. The light profiles obtained by the method were compared to those detected by photo diodes. The experimental results demonstrate the feasibility of this method. The approach can play a significant role for photo-dosimetry in biomedical phototherapy.展开更多
The analytical mathematical solutions of gas concentration and fractional gas loss for the diffusion of gas in a cylindrical coal sample were given with detailed mathematical derivations by assuming that the diffusion...The analytical mathematical solutions of gas concentration and fractional gas loss for the diffusion of gas in a cylindrical coal sample were given with detailed mathematical derivations by assuming that the diffusion of gas through the coal matrix is concentration gradient-driven and obeys the Fick’s Second Law of Diffusion.The analytical solutions were approximated in case of small values of time and the error analyses associated with the approximation were also undertaken.The results indicate that the square root relationship of gas release in the early stage of desorption,which is widely used to provide a simple and fast estimation of the lost gas,is the first term of the approximation,and care must be taken in using the square root relationship as a significant error might be introduced with increase in the lost time and decrease in effective diameter of a cylindrical coal sample.展开更多
Permeation grouting is widely applied for its low grouting pressure and minor disturbance to the stratum in grouting engineering, especially in engineering with strict requirements on ground settlement. However, perme...Permeation grouting is widely applied for its low grouting pressure and minor disturbance to the stratum in grouting engineering, especially in engineering with strict requirements on ground settlement. However, permeation grouting theory lags behind compared with other engineering disciplines, and the theoretical formulas now available cannot accurately be used to guide grouting engineering design and predict the cost and effects of grouting due to many factors affecting grout permeation in stratum. In this study, permeation grouting experiment devices were independently manufactured with the characteristics of easily controlling grouting pressure, simulating sandy strata grout, and detecting grouting effect. Using a uniform design, the sand consolidation agent, as grouting material, its spread in Shenyang sandy strata was tested with these experiment devices. The quantitative relations between grouting factors （grouting pressure, strata parameters, water-sand consolidation agent ratio） and grouting effects （grout spread radius, gell strength, grout amount） are obtained with regression analysis, and the influence degree of grouting factors on grouting effects is studied.展开更多
基金This work is supported by the National Science Foundation of China Nos.61675043,61875038 and 81571726.
文摘In illuminating tissues,a cylindrical diffuser(CD)has an advantage over regular laser sources due to its ability to illuminate a larger volume of the target tissue.This paper presents a co-registered large volume photoacoustic(PA)and ultrasonic(US)imaging for early endometrial cancer(EEC)detection using CD.It has the advantage that the US imaging system is outside the body and only the PA excitation device is inside the body,which makes the system more efficient and less invasive for EEC detection.The paper reports on two sets of experiments.Thefirst set produced real-time PA images of blood vessel phantom.The second set demonstrated the imaging of pig uterus ex vivo.The results show that the system has the potential for imaging and characterizing of EEC.
基金supported by the National Natural Science Foundation of China(No.61178089/81201124)in part by the Natural Science Foundation of Fujian Province(No.2011Y0019)
文摘Measurement of light distribution in biological tissue contributes to selecting strategy and optimizing dose for biomedical application. In this letter, a photoacoustic method combined with Monte Carlo simulation was used to estimate the three-dimensional light distribution in biological tissue. The light distribution was produced by a cylindrical diffuser which interposed into tissues. The light profiles obtained by the method were compared to those detected by photo diodes. The experimental results demonstrate the feasibility of this method. The approach can play a significant role for photo-dosimetry in biomedical phototherapy.
基金provided by the Science and Technology Grant of Huainan City of China (No.2013A4001)the Key Research Grant of Shanxi Province of China (No.201303027-1)
文摘The analytical mathematical solutions of gas concentration and fractional gas loss for the diffusion of gas in a cylindrical coal sample were given with detailed mathematical derivations by assuming that the diffusion of gas through the coal matrix is concentration gradient-driven and obeys the Fick’s Second Law of Diffusion.The analytical solutions were approximated in case of small values of time and the error analyses associated with the approximation were also undertaken.The results indicate that the square root relationship of gas release in the early stage of desorption,which is widely used to provide a simple and fast estimation of the lost gas,is the first term of the approximation,and care must be taken in using the square root relationship as a significant error might be introduced with increase in the lost time and decrease in effective diameter of a cylindrical coal sample.
基金Supported by the National Science and Technology Support Plan of 12th Five-year Plan （2012BAK24B00, 2012BAK24B0104） the National Natural Science Foundation of China （51204029） the Fundamental Research Funds of Chinese Ministry of Education （N110301003）
文摘Permeation grouting is widely applied for its low grouting pressure and minor disturbance to the stratum in grouting engineering, especially in engineering with strict requirements on ground settlement. However, permeation grouting theory lags behind compared with other engineering disciplines, and the theoretical formulas now available cannot accurately be used to guide grouting engineering design and predict the cost and effects of grouting due to many factors affecting grout permeation in stratum. In this study, permeation grouting experiment devices were independently manufactured with the characteristics of easily controlling grouting pressure, simulating sandy strata grout, and detecting grouting effect. Using a uniform design, the sand consolidation agent, as grouting material, its spread in Shenyang sandy strata was tested with these experiment devices. The quantitative relations between grouting factors （grouting pressure, strata parameters, water-sand consolidation agent ratio） and grouting effects （grout spread radius, gell strength, grout amount） are obtained with regression analysis, and the influence degree of grouting factors on grouting effects is studied.
