As a non-destructive testing technology,neutron imaging plays an important role in various fields,including material science,nuclear engineering,and fundamental science.An imaging detector with a neutron-sensitive ima...As a non-destructive testing technology,neutron imaging plays an important role in various fields,including material science,nuclear engineering,and fundamental science.An imaging detector with a neutron-sensitive image intensifier has been developed and demonstrated to achieve good spatial resolution and timing resolution.However,the influence of the working voltage on the performance of the neutron-sensitive imaging intensifier has not been studied.To optimize the performance of the neutron-sensitive image intensifier at different voltages,experiments have been performed at the China Spallation Neutron Source(CSNS)neutron beamline.The change in the light yield and imaging quality with different voltages has been acquired.It is shown that the image quality benefits from the high gain of the microchannel plate(MCP)and the high accelerating electric field between the MCP and the screen.Increasing the accelerating electric field is more effective than increasing the gain of MCPs for the improvement of the imaging quality.Increasing the total gain of the MCP stack can be realized more effectively by improving the gain of the standard MCP than that of the n MCP.These results offer a development direction for image intensifiers in the future.展开更多
The efficient separation of amphoteric organic compounds from dilute solutions is of great importance in the industrial field. In the present work, the reactive extractions of 4-hydroxypyridine(4-HP) with tributyl pho...The efficient separation of amphoteric organic compounds from dilute solutions is of great importance in the industrial field. In the present work, the reactive extractions of 4-hydroxypyridine(4-HP) with tributyl phosphate(TBP), di(2-ethylhexyl) phosphoric acid(D2EHPA) and TBP + D2EHPA dissolved in 1-octanol were investigated, respectively. The influences of the initial concentrations of TBP, D2EHPA and TBP + D2EHPA on distribution ratio(D) were discussed, as well as the reactive extraction mechanism were proposed. The obvious intensification effect was observed when the mixture of TBP and D2EHPA was used as extractant. The best extraction conditions were found to be of the molar ratio of D2EHPA and TBP at 2:1 and the equilibrium aqueous pH at 3.50-4.50. D values increased with the increase of the total concentration of TBP and D2EHPA in 1-octanol. Especially, the analysis on the extraction mechanisms clearly indicate(i) TBP in 1-octanol shows negligible reactive extraction toward 4-HP,(ii) D2EHPA in 1-octanol exhibits moderate extraction effect by forming 4-HP:D2EHPA(1:1) and 4-HP:2D2EHPA(1:2) type complexes, while(iii) D2EHPA in TBP/1-octanol demonstrates the maximum distribution ratio with the 4-HP:D2EHPA(1:1) type complex domination. The discussion provides new insights on the mechanism and opens a new way for the intensified extraction of amphoteric organic compounds by using the mixture of multiple extractants in the diluent.展开更多
US-Philippines relations have been rapidly strengthened since Marcos Jr.became Philippine President.The strong revitalization of the special relationship based on traditional ties has not only had an impact on regiona...US-Philippines relations have been rapidly strengthened since Marcos Jr.became Philippine President.The strong revitalization of the special relationship based on traditional ties has not only had an impact on regional security hotspots,but also profoundly stirred up the security situation in the Asia-Pacific,especially in the context of intensified China-US strategic rivalry.However,prospects of the revitalization remain uncertain given,among others,the variables in domestic politics and the emergence of a“special dilemma”within the alliance.展开更多
The Chinese government attaches great importance to the legal protection of innovation and intellectual property rights.At the parallel forum named"Rule of Law and Innovation"with the theme of"Intellect...The Chinese government attaches great importance to the legal protection of innovation and intellectual property rights.At the parallel forum named"Rule of Law and Innovation"with the theme of"Intellectual Property and the Development of New Productive Forces"held during the Global Business and Law Conference2024,experts had a heated discussion.Zhang Shaogang,Vice Chairman of the CCPIT,said at the forum,"At present,the momentum of world economic growth is insufficient,and the competition in the frontier areas of the new round of scientific and technological revolution and industrial transformation has intensified.展开更多
This year marks the 50th anniversary of the establishment of diplomatic ties between China and Malaysia.Over the past half century,China and Malaysia have maintained close economic and trade ties and intensified peopl...This year marks the 50th anniversary of the establishment of diplomatic ties between China and Malaysia.Over the past half century,China and Malaysia have maintained close economic and trade ties and intensified people-to-people exchanges.China and Malaysia are important trade partners and enjoy complementary economic advantages.展开更多
CNPC achieved a high-quality“Good Start”in Q12024 On April 29,PetroChina Company Limited announced its Q12024 achievements,highlighting coordinated efforts in production and operations,safety and environmental prote...CNPC achieved a high-quality“Good Start”in Q12024 On April 29,PetroChina Company Limited announced its Q12024 achievements,highlighting coordinated efforts in production and operations,safety and environmental protection,quality improvement and efficiency enhancement,reform and innovation,and green transformation.The Company optimized operations and product mixes,intensified market outreach,and rigorously managed costs.Its oil and gas chains ran safely and efficiently,while new energy and materials sectors witnessed rapid growth.展开更多
基金Project supported by the National Key R&D Program of China (Grant Nos.2023YFC2206502 and 2021YFA1600703)the National Natural Science Foundation of China (Grant Nos.12175254 and 12227810)the Guangdong–Hong Kong–Macao Joint Laboratory for Neutron Scattering Science and Technology。
文摘As a non-destructive testing technology,neutron imaging plays an important role in various fields,including material science,nuclear engineering,and fundamental science.An imaging detector with a neutron-sensitive image intensifier has been developed and demonstrated to achieve good spatial resolution and timing resolution.However,the influence of the working voltage on the performance of the neutron-sensitive imaging intensifier has not been studied.To optimize the performance of the neutron-sensitive image intensifier at different voltages,experiments have been performed at the China Spallation Neutron Source(CSNS)neutron beamline.The change in the light yield and imaging quality with different voltages has been acquired.It is shown that the image quality benefits from the high gain of the microchannel plate(MCP)and the high accelerating electric field between the MCP and the screen.Increasing the accelerating electric field is more effective than increasing the gain of MCPs for the improvement of the imaging quality.Increasing the total gain of the MCP stack can be realized more effectively by improving the gain of the standard MCP than that of the n MCP.These results offer a development direction for image intensifiers in the future.
基金supported by the Science and Technology Research Project of Henan Province (192102310490 and 212102310505)。
文摘The efficient separation of amphoteric organic compounds from dilute solutions is of great importance in the industrial field. In the present work, the reactive extractions of 4-hydroxypyridine(4-HP) with tributyl phosphate(TBP), di(2-ethylhexyl) phosphoric acid(D2EHPA) and TBP + D2EHPA dissolved in 1-octanol were investigated, respectively. The influences of the initial concentrations of TBP, D2EHPA and TBP + D2EHPA on distribution ratio(D) were discussed, as well as the reactive extraction mechanism were proposed. The obvious intensification effect was observed when the mixture of TBP and D2EHPA was used as extractant. The best extraction conditions were found to be of the molar ratio of D2EHPA and TBP at 2:1 and the equilibrium aqueous pH at 3.50-4.50. D values increased with the increase of the total concentration of TBP and D2EHPA in 1-octanol. Especially, the analysis on the extraction mechanisms clearly indicate(i) TBP in 1-octanol shows negligible reactive extraction toward 4-HP,(ii) D2EHPA in 1-octanol exhibits moderate extraction effect by forming 4-HP:D2EHPA(1:1) and 4-HP:2D2EHPA(1:2) type complexes, while(iii) D2EHPA in TBP/1-octanol demonstrates the maximum distribution ratio with the 4-HP:D2EHPA(1:1) type complex domination. The discussion provides new insights on the mechanism and opens a new way for the intensified extraction of amphoteric organic compounds by using the mixture of multiple extractants in the diluent.
文摘US-Philippines relations have been rapidly strengthened since Marcos Jr.became Philippine President.The strong revitalization of the special relationship based on traditional ties has not only had an impact on regional security hotspots,but also profoundly stirred up the security situation in the Asia-Pacific,especially in the context of intensified China-US strategic rivalry.However,prospects of the revitalization remain uncertain given,among others,the variables in domestic politics and the emergence of a“special dilemma”within the alliance.
文摘The Chinese government attaches great importance to the legal protection of innovation and intellectual property rights.At the parallel forum named"Rule of Law and Innovation"with the theme of"Intellectual Property and the Development of New Productive Forces"held during the Global Business and Law Conference2024,experts had a heated discussion.Zhang Shaogang,Vice Chairman of the CCPIT,said at the forum,"At present,the momentum of world economic growth is insufficient,and the competition in the frontier areas of the new round of scientific and technological revolution and industrial transformation has intensified.
文摘This year marks the 50th anniversary of the establishment of diplomatic ties between China and Malaysia.Over the past half century,China and Malaysia have maintained close economic and trade ties and intensified people-to-people exchanges.China and Malaysia are important trade partners and enjoy complementary economic advantages.
文摘CNPC achieved a high-quality“Good Start”in Q12024 On April 29,PetroChina Company Limited announced its Q12024 achievements,highlighting coordinated efforts in production and operations,safety and environmental protection,quality improvement and efficiency enhancement,reform and innovation,and green transformation.The Company optimized operations and product mixes,intensified market outreach,and rigorously managed costs.Its oil and gas chains ran safely and efficiently,while new energy and materials sectors witnessed rapid growth.
