In the context of the new era of education,advanced mathematics not only undertakes the function of knowledge transmission but also plays a vital role in cultivating logical thinking,scientific spirit,and value orient...In the context of the new era of education,advanced mathematics not only undertakes the function of knowledge transmission but also plays a vital role in cultivating logical thinking,scientific spirit,and value orientation.However,traditional teaching has overemphasized knowledge instillation while neglecting value guidance,making it difficult to meet the demands of cultivating interdisciplinary talents.This study introduces the OBE concept and constructs a“knowledge–ability–value”teaching framework,integrating outcome orientation,backward design,and diversified evaluation to promote the systematic incorporation of ideological and political education into the curriculum.Taking limits,definite integrals,and series as representative knowledge points,the paper designs case-based pathways to foster dialectical thinking,patriotism,and scientific spirit.Practice has shown that this model effectively unifies knowledge education and value education,enhancing students’logical reasoning,sense of responsibility,and scientific literacy.The study provides an operational pathway for the reform of ideological and political education in advanced mathematics courses and carries practical significance for implementing the goal of“all-round education.”展开更多
The semicylindrical time projection chamber(scTPC)is designed to measure the angular distribution of the cross section for intermediate-energy(3He,t)charge-exchange reactions in inverse kinematics.The scTPC prototype ...The semicylindrical time projection chamber(scTPC)is designed to measure the angular distribution of the cross section for intermediate-energy(3He,t)charge-exchange reactions in inverse kinematics.The scTPC prototype comprises a cathode,field cage,drift region,amplification structure based on a multilayer thick gas electron multiplier(THGEM),and a readout plane with 886 zigzag-shaped pads.The gain uniformity of the THGEM and the drift velocity of electrons were calibrated.Track recognition based on the Hough transform was then developed to reconstruct cosmic ray tracks and determine their position resolution.The position resolution of secondary particle tracks resulting from collisions between the heavy-ion beam and the 3He target was measured,yielding an x-resolution of 0.71 mm and a z-resolution of 0.73 mm.The scTPC demonstrates sufficient energy and spatial resolution to support charge-exchange reaction experiments in inverse kinematics.展开更多
The neutron richness of the light charged particles emitted out of the fission plane in heavy ion reactions has been experimentally investigated via the production of A=3 mirror nuclei in ^(86)Kr+^(nat)Pb reactions at...The neutron richness of the light charged particles emitted out of the fission plane in heavy ion reactions has been experimentally investigated via the production of A=3 mirror nuclei in ^(86)Kr+^(nat)Pb reactions at 25 MeV/u.The energy spectra and angular distributions of triton(t)and ^(3)He in coincidence with two fission fragments are measured with the Compact Spectrometer for Heavy IoN Experiment(CSHINE).The energy spectrum of ^(3)He is observed harder than that of triton in the fission events,in accordance with the phenomena reported as“^(3)He-puzzle”in inclusive measurements.With a data-driven energy spectrum peak cut scenario,it is observed that the yield ratio R(t∕^(3)He)increases with the angle to the fission plane,showing an enhancement of neutron-rich particle emission from out-of-fission-plane.A qualitative comparison with the transport model calculations suggests that this observation may serve as a new probe for the nuclear symmetry energy.展开更多
The emergence of meal replacement(MR)originates from physical exercise or fitness as a substitute for one or all meals and later expands to the field of weight loss.Indeed,the main application of current meal replacem...The emergence of meal replacement(MR)originates from physical exercise or fitness as a substitute for one or all meals and later expands to the field of weight loss.Indeed,the main application of current meal replacement is to lose body weight,whether patients with obesity,diabetes,fatty liver,infertile or pregnant women can benefit from weight loss.In addition,MRs still exhibit more biomedical potential in preventing and treating diseases,like anti-diabetes,improving fatty liver and kidney disease,preventing cancer,conceiving and reducing pregnancy complications,and improving life quality.Indeed,there are also disadvantages to meal replacement,including causing adverse effects,although most are acceptable and tolerated.To date,various commercially-developed MRs are walking from dining table to sickbed.Therefore,a scientific understanding of the advantages and disadvantages of meal replacements is crucial for their extensive application beyond biomedical potentials.展开更多
A half-size prototype of the multi wire drift chamber for the cooling storage ring external-target experiment(CEE)was assembled and tested in the 350 MeV/u Kr+Fe reactions at the heavy-ion research facility in Lanzhou...A half-size prototype of the multi wire drift chamber for the cooling storage ring external-target experiment(CEE)was assembled and tested in the 350 MeV/u Kr+Fe reactions at the heavy-ion research facility in Lanzhou.The prototype consists of six sense layers,where the sense wires are stretched in three directions X,U,and V;meeting 0?,30?,and-30?,respectively,with respect to the vertical axis.The sensitive area of the prototype is 76 cm×76 cm.The amplified and shaped signals from the anode wires were digitized in a serial capacity array.When operating at a high voltage of 1500 V on the anode wires,the efficiency for each layer is greater than 95%.The tracking residual is approximately 301±2μm.This performance satisfies the requirements of CEE.展开更多
Machine transplanting and the application of slow-release nitrogen(N) fertilizer(SRNF) have played vital roles in the modernization of rice production. We aimed to determine the effects of potted-seedling transplantin...Machine transplanting and the application of slow-release nitrogen(N) fertilizer(SRNF) have played vital roles in the modernization of rice production. We aimed to determine the effects of potted-seedling transplanting—a new machine-transplanting method—and SRNF on hybrid rice yields. A 2-year splitplot experiment(2016–2017) was conducted in Meishan, Sichuan province, China, using two machinetransplanting methods(potted-seedling and blanket-seedling) and three N treatments. Total green leaf area, high-effective leaf area and its rate at heading, net photosynthetic rate of flag leaves 7 days after heading, glutamate synthase(GOGAT) and glutamine synthase(GS) activity after heading, dry matter production, and N accumulation at heading and maturity increased under the potted-seedling method or 70% SRNF as a base + 30% urea application at the panicle initiation stage(SBUP). Stem diameter and number of small and of all vascular bundles at the neck–panicle node in potted-seedling plants increased as a result of increasing numbers of effective panicles, secondary branches, and spikelets. In pottedseedling plants, treatment with SBUP increased the number of large and total vascular bundles at the panicle–neck internode and the number of differentiated and surviving secondary branches and spikelets and decreased the number of ineffective tillers and degenerated secondary branches and spikelets. We conclude that the potted-seedling machine transplanting method and SRNF combined with urea topdressing can strengthen the source–sink relationship in rice, resulting in higher yields.展开更多
In this report,a kinematical focusing technique will be briefly described,and using this technique,the primary hot isotope yields from the multiplicities of evaporated light particles,associated with isotopically iden...In this report,a kinematical focusing technique will be briefly described,and using this technique,the primary hot isotope yields from the multiplicities of evaporated light particles,associated with isotopically identified intermediate mass fragments,are reconstructed.Symmetry energy and characteristic properties of the fragmenting source at the time of the intermediate mass fragment formation are extracted from these reconstructed primary isotope yields using a self-consistent manner.The extracted density-dependent symmetry energy is further compared with those experimentally extracted from other heavy-ion reactions in literatures.A direct connection between the freeze-out concept and transport model simulations in a multifragmenting regime of heavy-ion collisions is also demonstrated quantitatively in the present work.展开更多
The study of yield traits can reveal the genetic architecture of grain yield for improving maize production.In this study, an association panel comprising 362 inbred lines and a recombinant inbred line population deri...The study of yield traits can reveal the genetic architecture of grain yield for improving maize production.In this study, an association panel comprising 362 inbred lines and a recombinant inbred line population derived from X178 × 9782 were used to identify candidate genes for nine yield traits. High-priority overlap(HPO) genes, which are genes prioritized in a genome-wide association study(GWAS), were investigated using coexpression networks. The GWAS identified 51 environmentally stable SNPs in two environments and 36 pleiotropic SNPs, including three SNPs with both attributes. Seven hotspots containing 41 trait-associated SNPs were identified on six chromosomes by permutation. Pyramiding of superior alleles showed a highly positive effect on all traits, and the phenotypic values of ear diameter and ear weight consistently corresponded with the number of superior alleles in tropical and temperate germplasm. A total of 61 HPO genes were detected after trait-associated SNPs were combined with the coexpression networks. Linkage mapping identified 16 environmentally stable and 16 pleiotropic QTL.Seven SNPs that were located in QTL intervals were assigned as consensus SNPs for the yield traits.Among the candidate genes predicted by our study, some genes were confirmed to function in seed development. The gene Zm00001 d016656 encoding a serine/threonine protein kinase was associated with five different traits across multiple environments. Some genes were uniquely expressed in specific tissues and at certain stages of seed development. These findings will provide genetic information and resources for molecular breeding of maize grain yield.展开更多
A magnetoelectrically permeable interface crack between two semi-infinite magnetoelectroelastic planes under the action of a heat flow and remote magnetoelectromechanical loadings is considered, where the assumption o...A magnetoelectrically permeable interface crack between two semi-infinite magnetoelectroelastic planes under the action of a heat flow and remote magnetoelectromechanical loadings is considered, where the assumption of frictionless contact between two dissimilar half-planes is adopted. Not only the solutions of the interface crack problem are presented in an explicit form, but also the general condition for the transition from a perfect thermal contact of two mag- netoelectroelastic bodies to their separation is given.展开更多
Obesity is a metabolic disorder due to over-accumulation of adipose tissue and ultimately becomes a“disease”.Brown adipose tissue(BAT)thermogenesis and white adipose tissue(WAT)browning emerge as a potential strateg...Obesity is a metabolic disorder due to over-accumulation of adipose tissue and ultimately becomes a“disease”.Brown adipose tissue(BAT)thermogenesis and white adipose tissue(WAT)browning emerge as a potential strategy of anti-obesity by dissipating energy as heat.However,drugs based on adipose tissue thermogenesis have not been successfully approved yet.In current study,we found that black tea extract(BTE)obtained by patentauthorized manufacturing process prevented body weight gain as novel thermogenic activator with reduction of adiposity,improvement of adipose distribution,and glucose metabolism improvement in diet-induced obesity mice.Mechanismly,anti-obesity effect of BTE depends on promoting BAT thermogenesis and WAT browning with upregulation of uncoupling protein 1(UCP1),especially visceral adipose tissue(VAT)with browning resistance.Specifically,utilizing in silico approach of network pharmacology and molecular docking,we identified carbonic anhydrase 2(CA2)in nitrogen metabolism as anti-obesity target of BTE and further elucidated that protein kinase B(AKT)signaling pathway linked CA2 and UCP1.Meanwhile gut microbiota regulation may prompt the CA2-dependent thermogenesis activation.Our findings demonstrated anti-obesity effect of BTE as thermogenic activator through CA2-mediated BAT thermogenesis and WAT browning via CA2-AKT-UCP1 signaling pathway,which could be developed as promising anti-obesity agent with good safety and efficacy.展开更多
The cooling storage ring(CSR)external-target experiment(CEE)is a spectrometer used in construction to study the properties of nuclear matter in high-baryon density regions at the Heavy-Ion Research Facility in Lanzhou...The cooling storage ring(CSR)external-target experiment(CEE)is a spectrometer used in construction to study the properties of nuclear matter in high-baryon density regions at the Heavy-Ion Research Facility in Lanzhou(HIRFL).This study presents the design,simulation,manufacturing,and testing of a half-size prototype of a multi-wire drift chamber(MWDC)for the CEE.First,the performance of the MWDC connected to homemade electronics was simulated.The results demonstrated that an energy resolution of 18.5% for 5.9-keV X-rays and a position resolution of 194μm for protons can be achieved by the current design.Because the size of the largest MWDC reached 176 cm×314 cm,a set of 98 cm×98 cm prototypes was built using the new techniques.The positioning accuracy of the anode wires in this prototype is better than 20μm.After optimization,using commercially available electronics,the prototype can achieved an energy resolution of 19.7%for a^(55)Fe X-ray source.The CEE-MWDC detector and electronics were simultaneously tested.An energy resolution of 22%was achieved for the^(55)Fe source;the track residuals were approximately 330μm for the cosmic rays.The results demonstrate that the current design and techniques meet the requirements of the CEE-MWDC array.展开更多
Invariant-mass spectroscopy has been performed to search for possible resonance states in the loosely bound neutron-rich15C nucleus.By detecting alpha and11Be in coincidence,we reconstruct the excitation energy spectr...Invariant-mass spectroscopy has been performed to search for possible resonance states in the loosely bound neutron-rich15C nucleus.By detecting alpha and11Be in coincidence,we reconstruct the excitation energy spectrum for15C.To estimate the physical background from non-resonant prompt alpha particles,we employ a recently proposed weighted event-mixing method with phenomenological reduced weighting at around the alpha-decay threshold to account for the depletion in the prompt alpha's contribution owing likely to the Coulomb final-state interactions.A new weighted mixed-event method that focuses on a robust treatment of the Coulomb effect is also proposed.Through fitting the spectrum using the background estimated with these two methods,up to two resonance state candidates are proposed.Further experiments with improved statistics and theoretical calculations are called for to confirm the se resonance states.展开更多
A prototype thick-GEM-based cooling storage ring external-target experiment(CEE) time projection chamber(TPC) is constructed and tested with the pulsed ultraviolet laser beams. The results indicate that the prototype ...A prototype thick-GEM-based cooling storage ring external-target experiment(CEE) time projection chamber(TPC) is constructed and tested with the pulsed ultraviolet laser beams. The results indicate that the prototype TPC has a good performance in three-dimensional track resolution. In X direction the position resolution is about 0.2 mm, and in Y direction the position resolution is about 0.5 mm. The results also determine that the energy resolution is about 5.4%, which achieve the requirements of the CEE experiment and can be used to study the nuclear state equation and the quantum chromo dynamics.展开更多
A prototype beam monitor was designed to provide tracking information for heavy-ion projectiles for the cool storage ring(CSR)external target experiment(CEE)at the Heavy Ion Research Facility in Lanzhou(HIRFL).High gr...A prototype beam monitor was designed to provide tracking information for heavy-ion projectiles for the cool storage ring(CSR)external target experiment(CEE)at the Heavy Ion Research Facility in Lanzhou(HIRFL).High granularity and direct charge sensing are the main features of this device.It measures the beam position in a two-dimensional(2D)plane transverse to the beam direction on an event-by-event basis.The current design consists of two field cages inside a single vessel that operates independently and has electrical drift fields in orthogonal directions.Preliminary tests of the prototype were performed using a^(241)Am a source.The results show that a spatial resolution of less than 40μm and a time resolution of less than 600 ns can be achieved.展开更多
A new and innovative detector system based on a silicon strip detector dedicated to the study of the reaction induced by lighter radioactive beams is described herein.The detector system consists of five sets of three...A new and innovative detector system based on a silicon strip detector dedicated to the study of the reaction induced by lighter radioactive beams is described herein.The detector system consists of five sets of three types of telescopes,which are successfully used to measure the angular distributions of both elastic scattering and breakup simultaneously, on the Radioactive Ion Beam Line in Lanzhou at Heavy Ion Research Facility in Lanzhou. This silicon detector array is used to measure the elastic scattering angular distributions of ^(11) Be on a ^(208) Pb target at E_(lab) = 140 and 209 MeV. A comparison of the Monte Carlo simulations with the experimental results shows a reasonable consistency.展开更多
A detector setup for the measurement of angular distribution of heavy-ion elastic scattering at energies around Coulomb barrier on the radioactive ion beam line in Lanzhou at the heavy-ion research facility in Lanzhou...A detector setup for the measurement of angular distribution of heavy-ion elastic scattering at energies around Coulomb barrier on the radioactive ion beam line in Lanzhou at the heavy-ion research facility in Lanzhou is designed.The beam profile and the scattering angles on the target are deduced by two parallel plate avalanche counters,and four sets of detector telescopes(including doublesided silicon strip detectors) are placed systematically with the beam line,incorporating with Monte Carlo simulations.The data of ^(16)O on ^(89)Y target were analyzed to compare with the simulation results.It is found that the simulated distribution is agreeable with the experimental data.By assuming the pure Rutherford scattering at small scattering angles,the angular distribution of elastic scattering of^(16)O+^(89)Y at low energies can be reasonably obtained.It indicates that this set of detector setup can be used for the measurement of angular distributions of heavy-ion elastic scattering at energies around Coulomb barrier.展开更多
In this study,we constructed two annular detector arrays comprising 24 wedge-shaped CsI(Tl) crystals,and tested them using anαsource and radioactive beams of ^(14-16) Con a CD_2 target.We compared the properties of a...In this study,we constructed two annular detector arrays comprising 24 wedge-shaped CsI(Tl) crystals,and tested them using anαsource and radioactive beams of ^(14-16) Con a CD_2 target.We compared the properties of a CsI(Tl) crystal encapsulated with various reflectors,revealing that using the 80-μm-thick ESR film to pack the CsI(Tl) crystal yielded the largest light output with the smallest non-uniformity in light output (ΔLO).For the 24 CsI(Tl) detectors with the 80-μm-thick ESR films,the average energy resolution improved as the average light output increased;however,it deteriorated as theΔLO value increased.To form two annular Si-CsI(Tl) telescopes for identifying the light-charged particles,theΔLO value and energy resolution of each CsI(Tl) detector were maintained under 20%and 7.7%,respectively.These telescopes were tested for the first time in a direct nuclear reaction experiment using ^(14-16) C+d.The results demonstrated that the Z=1 and Z=2 charged particles were adequately discriminated by the telescopes using the standardΔE-E method.展开更多
A tracking system composed of three multiwires proportional chambers(MWPCs) for the external target facility of the Cooler Storage Ring is reported in this paper. The active areas of the MWPCs are 518 mm 9400 mm, 582 ...A tracking system composed of three multiwires proportional chambers(MWPCs) for the external target facility of the Cooler Storage Ring is reported in this paper. The active areas of the MWPCs are 518 mm 9400 mm, 582 mm 9 450 mm, and 710 mm 9 500 mm Each MWPC consists of a series of alternately placed cathode and anode wire planes and can measure position along the directions of-30°, 0°, and 30° relative to horizontal. The construction and operation of the detectors are described, and a method for track reconstruction is introduced. A track-finding efficiency of about 62% and a spatial resolution of 1.21 mm have been achieved. The pion and proton can be identified clearly with the tracking system combined with a time-of-flight system.展开更多
In this paper,the implantation-decay method is introduced to study the β-delayed charged particle decay.A silicon detector array was used for the implantation of the incident beams and for the detection of the emitte...In this paper,the implantation-decay method is introduced to study the β-delayed charged particle decay.A silicon detector array was used for the implantation of the incident beams and for the detection of the emitted particles.An experimental measurement on the β-delayed particle emission from ^(22)Al was used to demonstrate the method.The half-life value,charged particle spectroscopy,γ ray spectrum,and γ particle coincidence for the decay process were obtained and compared with previous experimental results for ^(22)Al.The results show that the implantation-decay method,using a silicon detector array,is a suitable experimental method to study the β-delayed charged particle decay for proton-rich nuclei.展开更多
The compact spectrometer for heavy ion experiment(CSHINE)is under construction for the study of isospin chronology via the Hanbury Brown–Twiss(HBT)particle correlation function and the nuclear equation of state of as...The compact spectrometer for heavy ion experiment(CSHINE)is under construction for the study of isospin chronology via the Hanbury Brown–Twiss(HBT)particle correlation function and the nuclear equation of state of asymmetrical nuclear matter.The CSHINE consists of silicon strip detector(SSD)telescopes and large-area parallel-plate avalanche counters,which measure the light charged particles and fission fragments,respectively.In phase I,two SSD telescopes were used to observe 30 MeV/u 40Ar?197Au reactions.The results presented here demonstrate that hydrogen and helium were observed with high isotopic resolution,and the HBT correlation functions of light charged particles could be constructed from the obtained data.展开更多
基金2024 Education and Teaching Reform Project(Project No.:JG2024047)Basic Scientific Research Funding of the Xinjiang Uygur Autonomous Region(Project No.:XQZX20250005)。
文摘In the context of the new era of education,advanced mathematics not only undertakes the function of knowledge transmission but also plays a vital role in cultivating logical thinking,scientific spirit,and value orientation.However,traditional teaching has overemphasized knowledge instillation while neglecting value guidance,making it difficult to meet the demands of cultivating interdisciplinary talents.This study introduces the OBE concept and constructs a“knowledge–ability–value”teaching framework,integrating outcome orientation,backward design,and diversified evaluation to promote the systematic incorporation of ideological and political education into the curriculum.Taking limits,definite integrals,and series as representative knowledge points,the paper designs case-based pathways to foster dialectical thinking,patriotism,and scientific spirit.Practice has shown that this model effectively unifies knowledge education and value education,enhancing students’logical reasoning,sense of responsibility,and scientific literacy.The study provides an operational pathway for the reform of ideological and political education in advanced mathematics courses and carries practical significance for implementing the goal of“all-round education.”
基金was supported by National Key R&D Program of China(No.2022YFE0103900)the National Natural Science Foundation of China(Nos.11875301,11875302,U1867214,U1832105,U2032166 and U1832167)+2 种基金the Fundamental Research Funds for the Central Universities(No.lzujbky-2022-sp06)the CAS“Light of West China”Programthe Heavy Ion Research Facility in Lanzhou。
文摘The semicylindrical time projection chamber(scTPC)is designed to measure the angular distribution of the cross section for intermediate-energy(3He,t)charge-exchange reactions in inverse kinematics.The scTPC prototype comprises a cathode,field cage,drift region,amplification structure based on a multilayer thick gas electron multiplier(THGEM),and a readout plane with 886 zigzag-shaped pads.The gain uniformity of the THGEM and the drift velocity of electrons were calibrated.Track recognition based on the Hough transform was then developed to reconstruct cosmic ray tracks and determine their position resolution.The position resolution of secondary particle tracks resulting from collisions between the heavy-ion beam and the 3He target was measured,yielding an x-resolution of 0.71 mm and a z-resolution of 0.73 mm.The scTPC demonstrates sufficient energy and spatial resolution to support charge-exchange reaction experiments in inverse kinematics.
基金the National Natural Science Foundation of China(Nos.12205160,11961131010,11961141004,and 11965004)by the Ministry of Science and Technology of China(Nos.2022YFE0103400 and 2020YFE0202001)+2 种基金by the Polish National Science Center(No.2023/49/B/ST2/01294)This work is also supported by Initiative Scientific Research Program and the Center of High Performance Computing of Tsinghua Universitythe Heavy Ion Research Facility at Lanzhou(HIRFL).
文摘The neutron richness of the light charged particles emitted out of the fission plane in heavy ion reactions has been experimentally investigated via the production of A=3 mirror nuclei in ^(86)Kr+^(nat)Pb reactions at 25 MeV/u.The energy spectra and angular distributions of triton(t)and ^(3)He in coincidence with two fission fragments are measured with the Compact Spectrometer for Heavy IoN Experiment(CSHINE).The energy spectrum of ^(3)He is observed harder than that of triton in the fission events,in accordance with the phenomena reported as“^(3)He-puzzle”in inclusive measurements.With a data-driven energy spectrum peak cut scenario,it is observed that the yield ratio R(t∕^(3)He)increases with the angle to the fission plane,showing an enhancement of neutron-rich particle emission from out-of-fission-plane.A qualitative comparison with the transport model calculations suggests that this observation may serve as a new probe for the nuclear symmetry energy.
基金funded by the National Natural Science Foundation of China(82070877)the CAMS Innovation Fund for Medical Sciences(CIFMS)(2021-I2M-1-028,2021-I2M-1-005)the International Cooperation Project of Qinghai Province(2020-HZ-803)。
文摘The emergence of meal replacement(MR)originates from physical exercise or fitness as a substitute for one or all meals and later expands to the field of weight loss.Indeed,the main application of current meal replacement is to lose body weight,whether patients with obesity,diabetes,fatty liver,infertile or pregnant women can benefit from weight loss.In addition,MRs still exhibit more biomedical potential in preventing and treating diseases,like anti-diabetes,improving fatty liver and kidney disease,preventing cancer,conceiving and reducing pregnancy complications,and improving life quality.Indeed,there are also disadvantages to meal replacement,including causing adverse effects,although most are acceptable and tolerated.To date,various commercially-developed MRs are walking from dining table to sickbed.Therefore,a scientific understanding of the advantages and disadvantages of meal replacements is crucial for their extensive application beyond biomedical potentials.
基金supported by the National Natural Science Foundation of China(Nos.11927901,11875301,11875302,U1867214,U1832105,U1832167)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB34000000)+2 种基金the National Key R&D Program of China(No.2018YFE0205200)the CAS"Light of West China"Programthe Tsinghua University Initiative Scientific Research Program。
文摘A half-size prototype of the multi wire drift chamber for the cooling storage ring external-target experiment(CEE)was assembled and tested in the 350 MeV/u Kr+Fe reactions at the heavy-ion research facility in Lanzhou.The prototype consists of six sense layers,where the sense wires are stretched in three directions X,U,and V;meeting 0?,30?,and-30?,respectively,with respect to the vertical axis.The sensitive area of the prototype is 76 cm×76 cm.The amplified and shaped signals from the anode wires were digitized in a serial capacity array.When operating at a high voltage of 1500 V on the anode wires,the efficiency for each layer is greater than 95%.The tracking residual is approximately 301±2μm.This performance satisfies the requirements of CEE.
基金supported by the National Key Research and Development Program of China(2017YFD0301701 and 2017YFD0301706)National Natural Science Foundation of China(31660369)。
文摘Machine transplanting and the application of slow-release nitrogen(N) fertilizer(SRNF) have played vital roles in the modernization of rice production. We aimed to determine the effects of potted-seedling transplanting—a new machine-transplanting method—and SRNF on hybrid rice yields. A 2-year splitplot experiment(2016–2017) was conducted in Meishan, Sichuan province, China, using two machinetransplanting methods(potted-seedling and blanket-seedling) and three N treatments. Total green leaf area, high-effective leaf area and its rate at heading, net photosynthetic rate of flag leaves 7 days after heading, glutamate synthase(GOGAT) and glutamine synthase(GS) activity after heading, dry matter production, and N accumulation at heading and maturity increased under the potted-seedling method or 70% SRNF as a base + 30% urea application at the panicle initiation stage(SBUP). Stem diameter and number of small and of all vascular bundles at the neck–panicle node in potted-seedling plants increased as a result of increasing numbers of effective panicles, secondary branches, and spikelets. In pottedseedling plants, treatment with SBUP increased the number of large and total vascular bundles at the panicle–neck internode and the number of differentiated and surviving secondary branches and spikelets and decreased the number of ineffective tillers and degenerated secondary branches and spikelets. We conclude that the potted-seedling machine transplanting method and SRNF combined with urea topdressing can strengthen the source–sink relationship in rice, resulting in higher yields.
基金supported by the Program for the CAS‘‘Light of West China’’Program(No.Y601030XB0)the National Basic Research Program of China(No.2014CB845405)the National Natural Science Foundation of China(Nos.11205209 and 11575256)
文摘In this report,a kinematical focusing technique will be briefly described,and using this technique,the primary hot isotope yields from the multiplicities of evaporated light particles,associated with isotopically identified intermediate mass fragments,are reconstructed.Symmetry energy and characteristic properties of the fragmenting source at the time of the intermediate mass fragment formation are extracted from these reconstructed primary isotope yields using a self-consistent manner.The extracted density-dependent symmetry energy is further compared with those experimentally extracted from other heavy-ion reactions in literatures.A direct connection between the freeze-out concept and transport model simulations in a multifragmenting regime of heavy-ion collisions is also demonstrated quantitatively in the present work.
基金funded and supported by China Agriculture Research System of MOF and MARA,Sichuan Science and Technology Support Project(2021YFYZ0020,2021YFYZ0027,2021YFFZ0017)National Natural Science Foundation of China(31971955)Sichuan Science and Technology Program(2019YJ0418,2020YJ0138)。
文摘The study of yield traits can reveal the genetic architecture of grain yield for improving maize production.In this study, an association panel comprising 362 inbred lines and a recombinant inbred line population derived from X178 × 9782 were used to identify candidate genes for nine yield traits. High-priority overlap(HPO) genes, which are genes prioritized in a genome-wide association study(GWAS), were investigated using coexpression networks. The GWAS identified 51 environmentally stable SNPs in two environments and 36 pleiotropic SNPs, including three SNPs with both attributes. Seven hotspots containing 41 trait-associated SNPs were identified on six chromosomes by permutation. Pyramiding of superior alleles showed a highly positive effect on all traits, and the phenotypic values of ear diameter and ear weight consistently corresponded with the number of superior alleles in tropical and temperate germplasm. A total of 61 HPO genes were detected after trait-associated SNPs were combined with the coexpression networks. Linkage mapping identified 16 environmentally stable and 16 pleiotropic QTL.Seven SNPs that were located in QTL intervals were assigned as consensus SNPs for the yield traits.Among the candidate genes predicted by our study, some genes were confirmed to function in seed development. The gene Zm00001 d016656 encoding a serine/threonine protein kinase was associated with five different traits across multiple environments. Some genes were uniquely expressed in specific tissues and at certain stages of seed development. These findings will provide genetic information and resources for molecular breeding of maize grain yield.
基金supported by the National Natural Science Foundation of China (Nos. 10772123 and 11072160)the Program for Changjiang Scholars and Innovative Research Team in University (No. IRT0971)the Natural Science Fund for Outstanding Younger of Hebei Province (A2009001624), China
文摘A magnetoelectrically permeable interface crack between two semi-infinite magnetoelectroelastic planes under the action of a heat flow and remote magnetoelectromechanical loadings is considered, where the assumption of frictionless contact between two dissimilar half-planes is adopted. Not only the solutions of the interface crack problem are presented in an explicit form, but also the general condition for the transition from a perfect thermal contact of two mag- netoelectroelastic bodies to their separation is given.
基金funded by National Natural Science Foundation of China(NSFC 82070877)CAMS Innovation Fund for Medical Sciences(CIFMS)(2022-I2M-JB-010,2021-I2M-1-005)The National High Technology Research and Development Program of China(2017YFE0112900).
文摘Obesity is a metabolic disorder due to over-accumulation of adipose tissue and ultimately becomes a“disease”.Brown adipose tissue(BAT)thermogenesis and white adipose tissue(WAT)browning emerge as a potential strategy of anti-obesity by dissipating energy as heat.However,drugs based on adipose tissue thermogenesis have not been successfully approved yet.In current study,we found that black tea extract(BTE)obtained by patentauthorized manufacturing process prevented body weight gain as novel thermogenic activator with reduction of adiposity,improvement of adipose distribution,and glucose metabolism improvement in diet-induced obesity mice.Mechanismly,anti-obesity effect of BTE depends on promoting BAT thermogenesis and WAT browning with upregulation of uncoupling protein 1(UCP1),especially visceral adipose tissue(VAT)with browning resistance.Specifically,utilizing in silico approach of network pharmacology and molecular docking,we identified carbonic anhydrase 2(CA2)in nitrogen metabolism as anti-obesity target of BTE and further elucidated that protein kinase B(AKT)signaling pathway linked CA2 and UCP1.Meanwhile gut microbiota regulation may prompt the CA2-dependent thermogenesis activation.Our findings demonstrated anti-obesity effect of BTE as thermogenic activator through CA2-mediated BAT thermogenesis and WAT browning via CA2-AKT-UCP1 signaling pathway,which could be developed as promising anti-obesity agent with good safety and efficacy.
基金supported by the Research Program of the National Major Research Instruments(No.11927901)Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB34000000)+3 种基金the Function Development Project of Chinese Academy of Sciences(No.2022G101)National Key R&D Program of China(No.2018YFE0205200)Natural Science Foundation of China(Nos.11875301,11875302,U1867214,U1832105,U1832167)CAS"Light of West China"Program。
文摘The cooling storage ring(CSR)external-target experiment(CEE)is a spectrometer used in construction to study the properties of nuclear matter in high-baryon density regions at the Heavy-Ion Research Facility in Lanzhou(HIRFL).This study presents the design,simulation,manufacturing,and testing of a half-size prototype of a multi-wire drift chamber(MWDC)for the CEE.First,the performance of the MWDC connected to homemade electronics was simulated.The results demonstrated that an energy resolution of 18.5% for 5.9-keV X-rays and a position resolution of 194μm for protons can be achieved by the current design.Because the size of the largest MWDC reached 176 cm×314 cm,a set of 98 cm×98 cm prototypes was built using the new techniques.The positioning accuracy of the anode wires in this prototype is better than 20μm.After optimization,using commercially available electronics,the prototype can achieved an energy resolution of 19.7%for a^(55)Fe X-ray source.The CEE-MWDC detector and electronics were simultaneously tested.An energy resolution of 22%was achieved for the^(55)Fe source;the track residuals were approximately 330μm for the cosmic rays.The results demonstrate that the current design and techniques meet the requirements of the CEE-MWDC array.
基金Supported partially by the National Natural Science Foundation of China (12175009, 12175280, 12250610193, 11605253, 12275007)National Key Research and Development Program of China (2023YFA1606702)+3 种基金the International Partnership Program of the Chinese Academy of Sciences (016GJHZ2023063GC)Major Science and Technology Projects in Gansu Province (24GD13GA005)the support of the CAS “Light of West China” Programthe support of the Natural Science Foundation of Gansu (23JRRA676)。
文摘Invariant-mass spectroscopy has been performed to search for possible resonance states in the loosely bound neutron-rich15C nucleus.By detecting alpha and11Be in coincidence,we reconstruct the excitation energy spectrum for15C.To estimate the physical background from non-resonant prompt alpha particles,we employ a recently proposed weighted event-mixing method with phenomenological reduced weighting at around the alpha-decay threshold to account for the depletion in the prompt alpha's contribution owing likely to the Coulomb final-state interactions.A new weighted mixed-event method that focuses on a robust treatment of the Coulomb effect is also proposed.Through fitting the spectrum using the background estimated with these two methods,up to two resonance state candidates are proposed.Further experiments with improved statistics and theoretical calculations are called for to confirm the se resonance states.
基金supported by the National Key Research and Development Program of China(Nos.2016YFA0400502 and 2015CB856904)the National Natural Science Foundation of China(Nos.U1332129,11475243,11421505,11775288 and 11405005)the ‘‘100-talent plan’’ of Shanghai Institute of Applied Physics from the Chinese Academy of Sciences(Nos.Y290061011 and Y526011011)
文摘A prototype thick-GEM-based cooling storage ring external-target experiment(CEE) time projection chamber(TPC) is constructed and tested with the pulsed ultraviolet laser beams. The results indicate that the prototype TPC has a good performance in three-dimensional track resolution. In X direction the position resolution is about 0.2 mm, and in Y direction the position resolution is about 0.5 mm. The results also determine that the energy resolution is about 5.4%, which achieve the requirements of the CEE experiment and can be used to study the nuclear state equation and the quantum chromo dynamics.
基金supported by the National Natural Science Foundation of China (Nos. 11927901, U2032209, 12005046)
文摘A prototype beam monitor was designed to provide tracking information for heavy-ion projectiles for the cool storage ring(CSR)external target experiment(CEE)at the Heavy Ion Research Facility in Lanzhou(HIRFL).High granularity and direct charge sensing are the main features of this device.It measures the beam position in a two-dimensional(2D)plane transverse to the beam direction on an event-by-event basis.The current design consists of two field cages inside a single vessel that operates independently and has electrical drift fields in orthogonal directions.Preliminary tests of the prototype were performed using a^(241)Am a source.The results show that a spatial resolution of less than 40μm and a time resolution of less than 600 ns can be achieved.
基金supported by the National Natural Science Foundation of China(Nos.U1432247,11575256,and U1632138)the CAS program of Light of West China Program under Grant(No.Y601030XB0)the National key R&D Program of China(No.2018YFA0404403)
文摘A new and innovative detector system based on a silicon strip detector dedicated to the study of the reaction induced by lighter radioactive beams is described herein.The detector system consists of five sets of three types of telescopes,which are successfully used to measure the angular distributions of both elastic scattering and breakup simultaneously, on the Radioactive Ion Beam Line in Lanzhou at Heavy Ion Research Facility in Lanzhou. This silicon detector array is used to measure the elastic scattering angular distributions of ^(11) Be on a ^(208) Pb target at E_(lab) = 140 and 209 MeV. A comparison of the Monte Carlo simulations with the experimental results shows a reasonable consistency.
基金Supported by the National Natural Science Foundation of China(Nos.11475013,11175011,11035007)
文摘A detector setup for the measurement of angular distribution of heavy-ion elastic scattering at energies around Coulomb barrier on the radioactive ion beam line in Lanzhou at the heavy-ion research facility in Lanzhou is designed.The beam profile and the scattering angles on the target are deduced by two parallel plate avalanche counters,and four sets of detector telescopes(including doublesided silicon strip detectors) are placed systematically with the beam line,incorporating with Monte Carlo simulations.The data of ^(16)O on ^(89)Y target were analyzed to compare with the simulation results.It is found that the simulated distribution is agreeable with the experimental data.By assuming the pure Rutherford scattering at small scattering angles,the angular distribution of elastic scattering of^(16)O+^(89)Y at low energies can be reasonably obtained.It indicates that this set of detector setup can be used for the measurement of angular distributions of heavy-ion elastic scattering at energies around Coulomb barrier.
基金supported by the National Natural Science Foundation of China (Nos.12275007, U1867214, 11775004)the funding from the State Key Laboratory of Nuclear Physics and Technology,Peking University,China (No. NPT2021ZZ01)funding from heavy Ion Research Facility,Lanzhou,China (No. HIR2021PY002)。
文摘In this study,we constructed two annular detector arrays comprising 24 wedge-shaped CsI(Tl) crystals,and tested them using anαsource and radioactive beams of ^(14-16) Con a CD_2 target.We compared the properties of a CsI(Tl) crystal encapsulated with various reflectors,revealing that using the 80-μm-thick ESR film to pack the CsI(Tl) crystal yielded the largest light output with the smallest non-uniformity in light output (ΔLO).For the 24 CsI(Tl) detectors with the 80-μm-thick ESR films,the average energy resolution improved as the average light output increased;however,it deteriorated as theΔLO value increased.To form two annular Si-CsI(Tl) telescopes for identifying the light-charged particles,theΔLO value and energy resolution of each CsI(Tl) detector were maintained under 20%and 7.7%,respectively.These telescopes were tested for the first time in a direct nuclear reaction experiment using ^(14-16) C+d.The results demonstrated that the Z=1 and Z=2 charged particles were adequately discriminated by the telescopes using the standardΔE-E method.
基金supported by the National Natural Science Foundation of China(Nos.U1332207,11222550,11405242 and 11305222)
文摘A tracking system composed of three multiwires proportional chambers(MWPCs) for the external target facility of the Cooler Storage Ring is reported in this paper. The active areas of the MWPCs are 518 mm 9400 mm, 582 mm 9 450 mm, and 710 mm 9 500 mm Each MWPC consists of a series of alternately placed cathode and anode wire planes and can measure position along the directions of-30°, 0°, and 30° relative to horizontal. The construction and operation of the detectors are described, and a method for track reconstruction is introduced. A track-finding efficiency of about 62% and a spatial resolution of 1.21 mm have been achieved. The pion and proton can be identified clearly with the tracking system combined with a time-of-flight system.
基金partially supported by the National Key R&D Program of China under Contract No.2018YFA0404404the National Natural Science Foundation of China under Contract Nos.11421505,11475244,and 11175231
文摘In this paper,the implantation-decay method is introduced to study the β-delayed charged particle decay.A silicon detector array was used for the implantation of the incident beams and for the detection of the emitted particles.An experimental measurement on the β-delayed particle emission from ^(22)Al was used to demonstrate the method.The half-life value,charged particle spectroscopy,γ ray spectrum,and γ particle coincidence for the decay process were obtained and compared with previous experimental results for ^(22)Al.The results show that the implantation-decay method,using a silicon detector array,is a suitable experimental method to study the β-delayed charged particle decay for proton-rich nuclei.
基金This work was supported by the National Natural Science Foundation of China(Nos.11875174 and 11961131010)。
文摘The compact spectrometer for heavy ion experiment(CSHINE)is under construction for the study of isospin chronology via the Hanbury Brown–Twiss(HBT)particle correlation function and the nuclear equation of state of asymmetrical nuclear matter.The CSHINE consists of silicon strip detector(SSD)telescopes and large-area parallel-plate avalanche counters,which measure the light charged particles and fission fragments,respectively.In phase I,two SSD telescopes were used to observe 30 MeV/u 40Ar?197Au reactions.The results presented here demonstrate that hydrogen and helium were observed with high isotopic resolution,and the HBT correlation functions of light charged particles could be constructed from the obtained data.
