In this study,we comprehensively characterized and optimized a cryogenic pure CsI(pCsI)detector.We utilized a 2 cm×2 cm×2 cm cube crystal coupled with a HAMAMATSU R11065 photomultiplier tube,achieving a rema...In this study,we comprehensively characterized and optimized a cryogenic pure CsI(pCsI)detector.We utilized a 2 cm×2 cm×2 cm cube crystal coupled with a HAMAMATSU R11065 photomultiplier tube,achieving a remarkable light yield of 35.2 PE/ke V_(ee)and an unprecedented energy resolution of 6.9%at 59.54 ke V.Additionally,we measured the scintillation decay time of pCsI,which was significantly shorter than that of CsI(Na)at room temperature.Furthermore,we investigated the impact of temperature,surface treatment and crystal shape on light yield.Notably,the light yield peaked at approximately 20 K and remained stable within the range of 70–100 K.The light yield of the polished crystals was approximately 1.5 times greater than that of the ground crystals,whereas the crystal shape exhibited minimal influence on the light yield.These results are crucial for the design of the 10 kg pCsI detector for the future CLOVERS(coherent elastic neutrino(V)-nucleus scattering at China Spallation Neutron Source(CSNS))experiment.展开更多
Tailoring of the composition of the scintillation ceramics Gd_(x)Ce_(0.03)Al_(2)Ga_(3)O_(12)(x=2.89-3.07) heavily doped with Ce was performed.The co-precipitation is found to be quite a useful method to provide a purp...Tailoring of the composition of the scintillation ceramics Gd_(x)Ce_(0.03)Al_(2)Ga_(3)O_(12)(x=2.89-3.07) heavily doped with Ce was performed.The co-precipitation is found to be quite a useful method to provide a purpo seful deviation of Gd content from the stoichio metric ratio in powders for their further compacting and sintering in the air.The effect of the composition variations on microstructure,phase composition,luminescent and scintillation characteristics is demonstrated.It is shown that Gd content below the stoichiometric composition leads to increasing the grain size but,quenching of the photoluminescence and the scintillation,whereas excess Gd leads to higher luminosity;the maximum value is obtained for the composition with an excess of Gd ~2%.Ceramics possess a light yield of -50000 ph/MeV,effective scintillation kinetics of 50 ns,and is a good candidate for application in a new generation of scanners utilizing pulsed X-ray sources.展开更多
The measurements of light yield of PbWO<sub>4</sub> crystals with normal methods may haverelatively large errors because the crystals have a low light yield.Therefore,a single photoelec-tron method with no...The measurements of light yield of PbWO<sub>4</sub> crystals with normal methods may haverelatively large errors because the crystals have a low light yield.Therefore,a single photoelec-tron method with normal radioactive sources is proposed and the measurements for severalPbWO<sub>4</sub> samples produced by Beijing Glass Research Institute are reported.展开更多
The development of low-cost and highly efficient thermal neutron detection materials to substitute the rare and expensive^(3)He gas is important for applications requiring thermal neutron detection.Lithium-based glass...The development of low-cost and highly efficient thermal neutron detection materials to substitute the rare and expensive^(3)He gas is important for applications requiring thermal neutron detection.Lithium-based glass(Li glass)is a promising candidate due to its simple fabrication process and low cost.This paper reports the optical properties and scintillation performance of a new Ce^(3+)-doped Li glass,whose luminescence efficiency is significantly enhanced with a light yield of about 4770 ph/MeV,which is about 54%of that of BGO crystal,and the energy resolution is 14.5%for 662 keV gamma rays.The Ce^(3+)-doped Li glass shows a high light yield of about 7058 ph/neutron,which is about 1.18 times that of the reference GS20 glass.The Ce^(3+)-doped Li glass exhibits stronger gamma ray suppression capability compared to GS20 glass samples.Further optimizing the Ce^(3+)concentration and 6Li content is expected to achieve much superior neutron detection efficiency,positioning it as a promising alternative to^(3)He gas for efficient thermal neutron detection.展开更多
The temperature dependence of BGO coupled with photomultiplier tube R5610A-01 was studied in the range of-30–30℃. The temperature coefficient of the BGO and R5610 A as a whole was tested to be-1.82%/℃. And the temp...The temperature dependence of BGO coupled with photomultiplier tube R5610A-01 was studied in the range of-30–30℃. The temperature coefficient of the BGO and R5610 A as a whole was tested to be-1.82%/℃. And the temperature coefficient of the gain of the R5610 A is-0.44%/℃ which was tested in the same situation using a blue LED. Thus the temperature coefficient of BGO's light yield can be evaluated as-1.38%/℃.展开更多
Heilongjiang Province is the main soybean-producing area in china. In this study, we analyzed the canopy structure, dynamic characteristics of light radiation and yield of Hefeng50 (the main variety of soybean in Heil...Heilongjiang Province is the main soybean-producing area in china. In this study, we analyzed the canopy structure, dynamic characteristics of light radiation and yield of Hefeng50 (the main variety of soybean in Heilongjiang Province) under six different cultivation patterns (ORP, TPCR, ORCP, BRHD, SRHD and FPHD). The results showed that SRHD and BRHD at different growth period (blossom period R1, podding R3 and grain filing period R5) produced an even distribution of the population leaf area, suitable mean foliage inclination angle (MFIA), low transparency coefficients for defuse penetration (TCDP) and transparency coefficients for radiation penetration (TCRP), high leaf area index (LAI), extinction light coefficient (K value), fraction of radiation intercepted (FRI) and light energy utilization rate. Grain number, dry matter weight per plant, and yield of SRHD and BRHD were significantly higher than those of other cultivation patterns. The yield of SRHD, BRHD, ORCP, FPHD and TPCR was increased by 136%, 112%, 79%, 50.1% and 14.7%, respectively, compared to that of ORP. These results suggest that SRHD and BRHD are the optimal cultivation pattern for the improvement of soybean yield in phaeozem region of northeastern China.展开更多
Light intensity is one of the most important environmental factors that determine the basic characteristics of rice development. However, continuously cloudy weather or rainfall, especially during the grain-filling st...Light intensity is one of the most important environmental factors that determine the basic characteristics of rice development. However, continuously cloudy weather or rainfall, especially during the grain-filling stage, induces a significant loss in yield and results in poor grain quality. Stress caused by low light often creates severe meteorological disasters in some rice-growing regions worldwide. This review was based on our previous research and related research regarding the effects of low light on rice growth, yield and quality as well as the formation of grain, and mainly reviewed the physiological metabolism of rice plants, including characteristics of photosynthesis, activities of antioxidant enzymes in rice leaves and key enzymes involved in starch synthesis in grains, as well as the translocations of carbohydrate and nitrogen. These characteristics include various grain yield and rice quality components （milling and appearance as well as cooking, eating and nutritional qualities） under different rates of shading imposed at the vegetative or reproductive stages of rice plants. Furthermore, we discussed why grain yield and quality are reduced under the low light environment. Next, we summarized the need for future research that emphasizes methods can effectively improve rice grain yield and quality under low light stress. These research findings can provide a beneficial reference for rice cultivation management and breeding program in low light environments.展开更多
Oil resources are non- renewable and the utilization of oil resources should be sustainable andrational. Oil processing industry must, to the maximum extent, produce liquid transportation fuel and chemi-cal feedstocks...Oil resources are non- renewable and the utilization of oil resources should be sustainable andrational. Oil processing industry must, to the maximum extent, produce liquid transportation fuel and chemi-cal feedstocks, which can hardly be replaced by other forms of energy. Restructuring oil refineries in China,developing hydrocracking technologies and improving light oil yield are the significant means to achievethe sustainable development of petroleum processing industry.展开更多
Background: Within-canopy interception of photosynthetically active radiation(PAR) impacts yield and other agronomic traits in cotton(Gossypium hirsutum L.). Field experiments were conducted to investigate the influen...Background: Within-canopy interception of photosynthetically active radiation(PAR) impacts yield and other agronomic traits in cotton(Gossypium hirsutum L.). Field experiments were conducted to investigate the influence of 6 cotton varieties(they belong to 3 different plant types) on yield, yield distribution, light interception(LI), LI distribution and the relationship between yield formation and LI in Anyang, Henan, in 2014 and 2015.Result: The results showed that cotton cultivars with long branches(loose-type) intercepted more LI than did cultivars with short branches(compact-type), due to increased LI in the middle and upper canopy. Although loose-type varieties had greater LI, they did not yield significantly higher than compact-type varieties, due to decreased harvest index. Therefore, improving the harvest index by adjusting the source-to-sink relationship may further increase cotton yield for loose-type cotton. In addition, there was a positive relationship between reproductive organ biomass accumulation and canopy-accumulated LI, indicating that enhancing LI is important for yield improvement for each cultivar. Furthermore, yield distribution within the canopy was significantly linearly related to vertical LI distribution.Conclusion: Therefore, optimizing canopy structure of different plant type and subsequently optimizing LI distribution within the cotton canopy can effectively enhance the yield.展开更多
The Taishan Antineutrino Observatory(TAO)experiment features a top veto tracker system comprising 160 modules,each constructed from plastic scintillator(PS)strips,embedded wavelength shifting fibers(WLS-fibers),and si...The Taishan Antineutrino Observatory(TAO)experiment features a top veto tracker system comprising 160 modules,each constructed from plastic scintillator(PS)strips,embedded wavelength shifting fibers(WLS-fibers),and silicon photomultipliers.This article reports on the performance of all produced modules,focusing on the production and readout/trigger design,and providing insights into scintillation detectors based on WLS-fibers.Three types of trigger modes and their efficiencies were defined to comprehensively evaluate the performance of this unique design,which was verified through batch production,comprehensive measurement strategies,and quality inspection methods.In“module”mode,the detection(tagging)efficiency of the PS exceeded 99.67%at a 30-photoelectron threshold,and even in“AND”mode,it surpassed 99.60%at a 15-photoelectron threshold.The muon tagging efficiency satisfies the requirements of TAO.The production and performance of PS modules establish a benchmark for other experiments,with optimized optical fiber arrangements that enhance light yield and muon detection efficiency.展开更多
基金supported by the National Key R&D Program of China(No.2022YFA1602204)the National Natural Science Foundation of China(Nos.12175241,12221005)+2 种基金the Fundamental Research Funds for the Central Universitiesthe International Partnership Program of the Chinese Academy of Sciences(No.211134KYSB20200057)the Double First-Class University Project Foundation of USTC。
文摘In this study,we comprehensively characterized and optimized a cryogenic pure CsI(pCsI)detector.We utilized a 2 cm×2 cm×2 cm cube crystal coupled with a HAMAMATSU R11065 photomultiplier tube,achieving a remarkable light yield of 35.2 PE/ke V_(ee)and an unprecedented energy resolution of 6.9%at 59.54 ke V.Additionally,we measured the scintillation decay time of pCsI,which was significantly shorter than that of CsI(Na)at room temperature.Furthermore,we investigated the impact of temperature,surface treatment and crystal shape on light yield.Notably,the light yield peaked at approximately 20 K and remained stable within the range of 70–100 K.The light yield of the polished crystals was approximately 1.5 times greater than that of the ground crystals,whereas the crystal shape exhibited minimal influence on the light yield.These results are crucial for the design of the 10 kg pCsI detector for the future CLOVERS(coherent elastic neutrino(V)-nucleus scattering at China Spallation Neutron Source(CSNS))experiment.
基金Project supported by the NRC"Kurchatov Institute"(No.2834 dated 09.11.2021)the Russian Federation represented by the Ministry of Education and Science of Russia (Agreement No.075-11-2021-070 dated 19.08.2021)。
文摘Tailoring of the composition of the scintillation ceramics Gd_(x)Ce_(0.03)Al_(2)Ga_(3)O_(12)(x=2.89-3.07) heavily doped with Ce was performed.The co-precipitation is found to be quite a useful method to provide a purpo seful deviation of Gd content from the stoichio metric ratio in powders for their further compacting and sintering in the air.The effect of the composition variations on microstructure,phase composition,luminescent and scintillation characteristics is demonstrated.It is shown that Gd content below the stoichiometric composition leads to increasing the grain size but,quenching of the photoluminescence and the scintillation,whereas excess Gd leads to higher luminosity;the maximum value is obtained for the composition with an excess of Gd ~2%.Ceramics possess a light yield of -50000 ph/MeV,effective scintillation kinetics of 50 ns,and is a good candidate for application in a new generation of scanners utilizing pulsed X-ray sources.
基金The project supported by the Science Foundation of Beijingthe Foundation of Science College of Tsinghua University
文摘The measurements of light yield of PbWO<sub>4</sub> crystals with normal methods may haverelatively large errors because the crystals have a low light yield.Therefore,a single photoelec-tron method with normal radioactive sources is proposed and the measurements for severalPbWO<sub>4</sub> samples produced by Beijing Glass Research Institute are reported.
基金supported by the National Key R&D Program of China(Grant No.2023YFF0721700)the National Natural Science Foundation of China(Grant No.12475312).
文摘The development of low-cost and highly efficient thermal neutron detection materials to substitute the rare and expensive^(3)He gas is important for applications requiring thermal neutron detection.Lithium-based glass(Li glass)is a promising candidate due to its simple fabrication process and low cost.This paper reports the optical properties and scintillation performance of a new Ce^(3+)-doped Li glass,whose luminescence efficiency is significantly enhanced with a light yield of about 4770 ph/MeV,which is about 54%of that of BGO crystal,and the energy resolution is 14.5%for 662 keV gamma rays.The Ce^(3+)-doped Li glass shows a high light yield of about 7058 ph/neutron,which is about 1.18 times that of the reference GS20 glass.The Ce^(3+)-doped Li glass exhibits stronger gamma ray suppression capability compared to GS20 glass samples.Further optimizing the Ce^(3+)concentration and 6Li content is expected to achieve much superior neutron detection efficiency,positioning it as a promising alternative to^(3)He gas for efficient thermal neutron detection.
基金supported by the National Basic Research Program of China(Grant No.2010CB833002)the Strategic Priority Research Program on Space Science of the Chinese Academy of Sciences(Grant No.XDA04040202-4)
文摘The temperature dependence of BGO coupled with photomultiplier tube R5610A-01 was studied in the range of-30–30℃. The temperature coefficient of the BGO and R5610 A as a whole was tested to be-1.82%/℃. And the temperature coefficient of the gain of the R5610 A is-0.44%/℃ which was tested in the same situation using a blue LED. Thus the temperature coefficient of BGO's light yield can be evaluated as-1.38%/℃.
文摘Heilongjiang Province is the main soybean-producing area in china. In this study, we analyzed the canopy structure, dynamic characteristics of light radiation and yield of Hefeng50 (the main variety of soybean in Heilongjiang Province) under six different cultivation patterns (ORP, TPCR, ORCP, BRHD, SRHD and FPHD). The results showed that SRHD and BRHD at different growth period (blossom period R1, podding R3 and grain filing period R5) produced an even distribution of the population leaf area, suitable mean foliage inclination angle (MFIA), low transparency coefficients for defuse penetration (TCDP) and transparency coefficients for radiation penetration (TCRP), high leaf area index (LAI), extinction light coefficient (K value), fraction of radiation intercepted (FRI) and light energy utilization rate. Grain number, dry matter weight per plant, and yield of SRHD and BRHD were significantly higher than those of other cultivation patterns. The yield of SRHD, BRHD, ORCP, FPHD and TPCR was increased by 136%, 112%, 79%, 50.1% and 14.7%, respectively, compared to that of ORP. These results suggest that SRHD and BRHD are the optimal cultivation pattern for the improvement of soybean yield in phaeozem region of northeastern China.
文摘Light intensity is one of the most important environmental factors that determine the basic characteristics of rice development. However, continuously cloudy weather or rainfall, especially during the grain-filling stage, induces a significant loss in yield and results in poor grain quality. Stress caused by low light often creates severe meteorological disasters in some rice-growing regions worldwide. This review was based on our previous research and related research regarding the effects of low light on rice growth, yield and quality as well as the formation of grain, and mainly reviewed the physiological metabolism of rice plants, including characteristics of photosynthesis, activities of antioxidant enzymes in rice leaves and key enzymes involved in starch synthesis in grains, as well as the translocations of carbohydrate and nitrogen. These characteristics include various grain yield and rice quality components （milling and appearance as well as cooking, eating and nutritional qualities） under different rates of shading imposed at the vegetative or reproductive stages of rice plants. Furthermore, we discussed why grain yield and quality are reduced under the low light environment. Next, we summarized the need for future research that emphasizes methods can effectively improve rice grain yield and quality under low light stress. These research findings can provide a beneficial reference for rice cultivation management and breeding program in low light environments.
文摘Oil resources are non- renewable and the utilization of oil resources should be sustainable andrational. Oil processing industry must, to the maximum extent, produce liquid transportation fuel and chemi-cal feedstocks, which can hardly be replaced by other forms of energy. Restructuring oil refineries in China,developing hydrocracking technologies and improving light oil yield are the significant means to achievethe sustainable development of petroleum processing industry.
基金funded by the National Natural Science Foundation of China(31371561)
文摘Background: Within-canopy interception of photosynthetically active radiation(PAR) impacts yield and other agronomic traits in cotton(Gossypium hirsutum L.). Field experiments were conducted to investigate the influence of 6 cotton varieties(they belong to 3 different plant types) on yield, yield distribution, light interception(LI), LI distribution and the relationship between yield formation and LI in Anyang, Henan, in 2014 and 2015.Result: The results showed that cotton cultivars with long branches(loose-type) intercepted more LI than did cultivars with short branches(compact-type), due to increased LI in the middle and upper canopy. Although loose-type varieties had greater LI, they did not yield significantly higher than compact-type varieties, due to decreased harvest index. Therefore, improving the harvest index by adjusting the source-to-sink relationship may further increase cotton yield for loose-type cotton. In addition, there was a positive relationship between reproductive organ biomass accumulation and canopy-accumulated LI, indicating that enhancing LI is important for yield improvement for each cultivar. Furthermore, yield distribution within the canopy was significantly linearly related to vertical LI distribution.Conclusion: Therefore, optimizing canopy structure of different plant type and subsequently optimizing LI distribution within the cotton canopy can effectively enhance the yield.
基金supported by the General Program of the National Natural Science Foundation of China(No.12075087)National Key Research and Development Program of China(No.2022YFA1602002)+1 种基金Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA10011102)support from the Guangdong Provincial Key Laboratory of Advanced Particle Detection Technology。
文摘The Taishan Antineutrino Observatory(TAO)experiment features a top veto tracker system comprising 160 modules,each constructed from plastic scintillator(PS)strips,embedded wavelength shifting fibers(WLS-fibers),and silicon photomultipliers.This article reports on the performance of all produced modules,focusing on the production and readout/trigger design,and providing insights into scintillation detectors based on WLS-fibers.Three types of trigger modes and their efficiencies were defined to comprehensively evaluate the performance of this unique design,which was verified through batch production,comprehensive measurement strategies,and quality inspection methods.In“module”mode,the detection(tagging)efficiency of the PS exceeded 99.67%at a 30-photoelectron threshold,and even in“AND”mode,it surpassed 99.60%at a 15-photoelectron threshold.The muon tagging efficiency satisfies the requirements of TAO.The production and performance of PS modules establish a benchmark for other experiments,with optimized optical fiber arrangements that enhance light yield and muon detection efficiency.
