Picea spp.are a prominent component of the boreal,montane,and sub-alpine forests in the Northern Hemisphere,and have substantial economic importance due to their high quality fibre.However,performance and wood propert...Picea spp.are a prominent component of the boreal,montane,and sub-alpine forests in the Northern Hemisphere,and have substantial economic importance due to their high quality fibre.However,performance and wood properties of the genus have not been systematically evaluated in China.This study aimed to examine genetic variations in growth traits,phenology,and wood properties of 17 Picea species,(three from North America,two from Europe,and 12 from China),in response to specific climate factors using a randomized complete block design in a monsoonal,middle latitude area of China.Results show that all growth traits and wood properties significantly varied among species(P <0.00).Of the 17 species examined,P.abies and P.pungens were the tallest with heights of 2.5 and 1.9 m at 9 years old,respectively,90% and 50% greater than the average heights.Branch length,number,and angles of both P.abies and P.pungens were greater than those of the other species.Heights of P.glauca and P.omorika were20-33% greater than the average.Fast-growing species had high quantities of first lateral branches and large top whorl branch lengths.The taller species exhibited greater tracheid lengths and average tracheid lengths to radial central diameter ratios(TL/R_D2),but smaller cell wall thicknesses to tracheid radial lumen diameter ratios(WT/R_D1),which is favorable for pulp production.Correlation analysis revealed that height and ring width had significant positive correlations with latitude but strongly negative correlations with longitude.Height was positively correlated with average annual rainfalls,but negative correlations with average yearly sunshine.Due to the increased average annual sunshine at the China test site relative to the seed source,species such as P.abies,P.pungens,P.glauca,and P.omorika from wet,humid areas performed better than native species.Considering similar temperatures,precipitation may be the main factor affecting growth,which is beneficial for predicting the extent of spruce expansion.These results should encourage further testing and provide reference information for future exotic species studies in this part of China.展开更多
Long-wavelength fluorescence carbon dots (CDs) show great importance in multiple fields,especially for the biochemical sensing.Here,we proposed one type of CDs doped with nitrogen and sulfur through the hydrothermal m...Long-wavelength fluorescence carbon dots (CDs) show great importance in multiple fields,especially for the biochemical sensing.Here,we proposed one type of CDs doped with nitrogen and sulfur through the hydrothermal method,which exhibited obvious yellow-fluorescence in aqueous solution.Importantly,the fluorescence intensity of CDs decreased with pH decreasing in the acidic range,thus a linear relationship between pH and fluorescence intensity was established,exhibiting the potential of pH sensing.Additionally,introducing tigecycline into CDs resulted in their decreased fluorescence,thus,we further established a strategy of detecting tigecycline with the concentration range of 200 μM to 7 nM.Meanwhile,we elucidated the static quenching as the major mechanism for CDs responding tigecycline,which was induced by the formed new complex between CDs and tigecycline.Furthermore,the practicality of the method was verified by examining the recovery of tigecycline in the actual lake-water samples.展开更多
In this study,we systematically analyzed the ground state of uranium isotopes from 225 to 240.In our calculations,we used the covariant energy density functional of density-dependent meson exchange interaction(DDME2)w...In this study,we systematically analyzed the ground state of uranium isotopes from 225 to 240.In our calculations,we used the covariant energy density functional of density-dependent meson exchange interaction(DDME2)with separable pairing interaction(TMR).Using the multiple deformation constraint,we calculated the potential energy surface(PES)of the uranium isotopes for both even-even and even-odd nuclei with quadrupole and octupole deformation.Based on our calculation and upon comparing the experimental data and Hartree-Fock-Bogoliubov calculations with Gogny D1S calculation data,the ground state of uranium isotopes with reflection-asymmetric deformation was found to be preferred.展开更多
基金supported by the Thirteenth Five-Year Plan for Key & Research Projects of China(2017YFD0600606-09)the National Natural Science Foundation of China (NSFC31600541)the Science Foundation of China Post-doctor (2016M591053)。
文摘Picea spp.are a prominent component of the boreal,montane,and sub-alpine forests in the Northern Hemisphere,and have substantial economic importance due to their high quality fibre.However,performance and wood properties of the genus have not been systematically evaluated in China.This study aimed to examine genetic variations in growth traits,phenology,and wood properties of 17 Picea species,(three from North America,two from Europe,and 12 from China),in response to specific climate factors using a randomized complete block design in a monsoonal,middle latitude area of China.Results show that all growth traits and wood properties significantly varied among species(P <0.00).Of the 17 species examined,P.abies and P.pungens were the tallest with heights of 2.5 and 1.9 m at 9 years old,respectively,90% and 50% greater than the average heights.Branch length,number,and angles of both P.abies and P.pungens were greater than those of the other species.Heights of P.glauca and P.omorika were20-33% greater than the average.Fast-growing species had high quantities of first lateral branches and large top whorl branch lengths.The taller species exhibited greater tracheid lengths and average tracheid lengths to radial central diameter ratios(TL/R_D2),but smaller cell wall thicknesses to tracheid radial lumen diameter ratios(WT/R_D1),which is favorable for pulp production.Correlation analysis revealed that height and ring width had significant positive correlations with latitude but strongly negative correlations with longitude.Height was positively correlated with average annual rainfalls,but negative correlations with average yearly sunshine.Due to the increased average annual sunshine at the China test site relative to the seed source,species such as P.abies,P.pungens,P.glauca,and P.omorika from wet,humid areas performed better than native species.Considering similar temperatures,precipitation may be the main factor affecting growth,which is beneficial for predicting the extent of spruce expansion.These results should encourage further testing and provide reference information for future exotic species studies in this part of China.
基金supported by Natural Science Foundation of Chongqing,China(cstc2021jcyj-msxmx0027)Talent and Innovation Project of Beibei District in Chongqing(2022-11)Performance Incentive and Guidance Special Project of Scientific Research Organization,Chongqing Science and Technology(cstc2021jxjl130024).
文摘Long-wavelength fluorescence carbon dots (CDs) show great importance in multiple fields,especially for the biochemical sensing.Here,we proposed one type of CDs doped with nitrogen and sulfur through the hydrothermal method,which exhibited obvious yellow-fluorescence in aqueous solution.Importantly,the fluorescence intensity of CDs decreased with pH decreasing in the acidic range,thus a linear relationship between pH and fluorescence intensity was established,exhibiting the potential of pH sensing.Additionally,introducing tigecycline into CDs resulted in their decreased fluorescence,thus,we further established a strategy of detecting tigecycline with the concentration range of 200 μM to 7 nM.Meanwhile,we elucidated the static quenching as the major mechanism for CDs responding tigecycline,which was induced by the formed new complex between CDs and tigecycline.Furthermore,the practicality of the method was verified by examining the recovery of tigecycline in the actual lake-water samples.
基金Supported by the National Key Research and Development(R&D)Program(2022YFA1602403)the National Natural Science Foundation of China(12005303)+2 种基金the CNNC Youth Innovation Team Project Key Laboratory Fundthe Key Laboratory fund key projects(JCKY2023201C153-5)the Continuous Support Basic Scientific Research Project(BJ010261223282)。
文摘In this study,we systematically analyzed the ground state of uranium isotopes from 225 to 240.In our calculations,we used the covariant energy density functional of density-dependent meson exchange interaction(DDME2)with separable pairing interaction(TMR).Using the multiple deformation constraint,we calculated the potential energy surface(PES)of the uranium isotopes for both even-even and even-odd nuclei with quadrupole and octupole deformation.Based on our calculation and upon comparing the experimental data and Hartree-Fock-Bogoliubov calculations with Gogny D1S calculation data,the ground state of uranium isotopes with reflection-asymmetric deformation was found to be preferred.
