In 2024,the world witnessed further transformation and instability,marked by protracted and intensified geopolitical conflicts,repeated attempts to decouple and sever supply chains,and the rapid rise of the Global Sou...In 2024,the world witnessed further transformation and instability,marked by protracted and intensified geopolitical conflicts,repeated attempts to decouple and sever supply chains,and the rapid rise of the Global South.It has become all the more clear where the once-in-a-century transformations are heading.In 2024,China acted on the blueprint drawn up at the Third Plenary Session of the 20th Central Committee of the Communist Party of China(CPC),and made big strides in deepening reform comprehensively.Marking the 75th anniversary of the founding of New China,China carried forward its great cause of national development and pressed ahead with Chinese modernization with vigor and determination.展开更多
Metal foils have emerged as one of the promising materials for anode-free batteries due to their high energy density and scalability in production.The unclear lithium plating/stripping kinetics of metal foil current c...Metal foils have emerged as one of the promising materials for anode-free batteries due to their high energy density and scalability in production.The unclear lithium plating/stripping kinetics of metal foil current collectors in anode-free batteries was addressed by using the non-destructive distribution of relaxation times(DRT)analysis to systematically investigate the lithium transport behavior of 14 metal foils and its correlation with electrochemical performance.By integrating energy-dispersive spectro scopy(EDS),cyclic voltammetry(CV),and galvanostatic testing,the exceptional properties of indium(In),tin(Sn),and silver(Ag)were revealed:the Li-In alloying reaction exhibits high reversibility,Li-Sn alloys demonstrate outstanding cycling stability,and the Li-Ag solid-solution mechanism provides an ideal lithium deposition interface on the silver substrate.The DRT separates the polarization internal resistance of lithium ions passing through the SEI layer(R_(sei),τ2)and the polarization internal resistance of lithium ions undergoing charge transfer reaction at the electrolyte/electrode interface(R_(ct),τ3)by decoupling the electrochemical impedance spectroscopy(EIS).For the first time,the correlation betweenτ2,τ3,and the cycle life/Coulombic efficiency of alloy/solid-solution metals was established,while non-alloy metals are not suitable for this method due to differences in lithium deposition mechanisms.This study not only illuminates the structure-property relationship governing the lithium kinetics of metal foil electrodes but also provides a novel non-destructive analytical strategy and theoretical guidance for the rational design of stable anodes in high-energy-density batteries,facilitating the efficient screening and optimization of anode-free battery.展开更多
A performer breathes fire during Chinese New Year celebrations at Binondo district,considered the world’s oldest Chinatown,on January 29 in Manila,Philippines.The celebrations,lasting approximately 15 days,were fille...A performer breathes fire during Chinese New Year celebrations at Binondo district,considered the world’s oldest Chinatown,on January 29 in Manila,Philippines.The celebrations,lasting approximately 15 days,were filled with traditional activities such as family gatherings,lion dances,and the exchange of red envelopes,joining the vibrant cultural event observed by Chinese communities worldwide.展开更多
InAs/AlAs superlattice structures have significant potential for application in low-noise avalanche photodetectors.With their performance in practical applications linked to the fundamental physical properties of carr...InAs/AlAs superlattice structures have significant potential for application in low-noise avalanche photodetectors.With their performance in practical applications linked to the fundamental physical properties of carrier relaxation time,this study investigated the carrier relaxation times of InAs/AlAs superlattices across various monolayers,temperatures,and carrier concentrations.Our investigation indicated that relaxation times span several tens of picoseconds,confirming that high-quality interfaces do not significantly reduce relaxation times in the way defect states might.Moreover,our study demonstrates that adjustments to the superlattice period can effectively modulate both the bandgap and carrier relaxation times,potentially impacting the performance of avalanche photodiodes by altering the electron-phonon interaction pathways and bandgap width.We established that lower temperatures contribute to an increase in the bandgap and the suppression of high-frequency optical phonon vibrations,thereby lengthening the relaxation times.Additionally,our observations indicate that in InAs/AlAs superlattices,the relaxation time increases as the excitation power increases,owing to the phonon bottleneck effect.These insights into InAs/AlAs superlattice carrier dynamics highlight their applicability in enhancing avalanche photodetectors,and may contribute to the optimized design of superlattices for specific applications.展开更多
We present a comprehensive extension of the integral of first passage times(IFS)method to investigate the adsorption kinetics of polymers with multiple binding sites on planar surfaces.While effective for single-point...We present a comprehensive extension of the integral of first passage times(IFS)method to investigate the adsorption kinetics of polymers with multiple binding sites on planar surfaces.While effective for single-point adsorption,the original IFS method was limited in capturing the complex kinetics of multi-point adsorption due to inadequate reaction coordinates and theoretical frameworks.Our approach introduces a center-of-mass-based reaction coordinate and a generalized kinetic model that accounts for multi-barrier free energy landscapes characteristic of collective polymer diffusion and binding.This theoretical advancement,implemented using the adaptive bias force method for efficient sampling,enables prediction of adsorption kinetics across timescales from nanoseconds to seconds.Our results demonstrate that adsorption behavior is governed by two key factors:the number of binding monomers primarily controls desorption barriers and long-term stability,while the configuration of pre-adsorbed layers significantly modulates both adsorption and desorption rates.Polymers with three or more binding sites exhibit effectively irreversible adsorption due to exponentially increasing desorption barriers,whereas different adsorbed layer configurations lead to distinct equilibrium coverages and kinetic profiles.This extended IFS framework provides critical insights for designing functional surfaces in nanoscale sensing,macromolecular recognition,and tailored polymeric coatings where precise control over adsorption kinetics is essential.展开更多
近年来,科研论文的合著现象及其与论文影响力之间的关系受到广泛关注。本文以1997—2013年Financial Times TOP 45商学院国际期刊论文为研究对象,对作者数量与论文被引(高被引还是零被引)之间的关系进行实证研究,从论文影响力方面揭示...近年来,科研论文的合著现象及其与论文影响力之间的关系受到广泛关注。本文以1997—2013年Financial Times TOP 45商学院国际期刊论文为研究对象,对作者数量与论文被引(高被引还是零被引)之间的关系进行实证研究,从论文影响力方面揭示商学领域是否存在最佳科研合作规模。研究发现:①与单独作者相比,多作者合作对论文总被引频次具有显著的正向影响,而且多作者合作论文成为高被引的概率更高,而成为零被引的概率更低;②作者数量与论文总被引频次之间存在显著的倒U形关系;进一步研究发现,作者数量与高被引论文概率呈倒U形关系,而与零被引论文概率呈正U形关系,且转折点均约为3人,表明商学领域存在使论文成为高被引而避免成为零被引的最佳合作规模;③分时间阶段实证结果表明,基于高被引和零被引的论文最佳合作规模逐步由2~3人增加至3~4人。展开更多
Achieving a sustainable cropping system requires the efficient use of resources,particularly nitrogen(N).Nitrogen fertiliser is applied in most irrigated cotton fields to maximise yield potential,but plant fertiliser ...Achieving a sustainable cropping system requires the efficient use of resources,particularly nitrogen(N).Nitrogen fertiliser is applied in most irrigated cotton fields to maximise yield potential,but plant fertiliser recovery can be low.Identifying the crucial pathways of fertiliser remobilisation internally within cotton plants will lead to greater awareness of the plants’ability to match the N demands of the developing fruiting matter.This study investigated the fate of N fertiliser when applied to cotton at various dates,with the goal to improve N fertiliser recovery in a modern transgenic cotton cultivar.15N-labelled urea(10 atom%)was applied at multiple times and harvested at four key cotton growth stages(first square,early bolls,cut-out and maturity).Remobilised N was determined as the difference in the proportion of N fertiliser in individual plant components against the fertiliser utilised by the whole plant.The application of fertiliser N at first square resulted in 23%greater fertiliser N recovery at plant maturity compared to fertiliser N applied 100%pre-plant(P<0.001).The improvement was in-part due to higher N derived from the fertiliser(Ndff%)in the cotton seed(3%).Conversely,the Ndff%was higher in the stem(4%)and petioles(1%)when the fertiliser was applied pre-plant.In total,73%of plant N was remobilised to another plant organ,predominantly the seed(67%).Applying N fertiliser post-planting improved N recovery and lint yield compared to applying all fertiliser pre-plant.展开更多
Comprehensive studies on CO_(2)breakthrough times and flooding effects are crucial for optimizing CO_(2)flooding strategies.This study utilized numerical simulations to investigate the effects of hydraulic fractures,p...Comprehensive studies on CO_(2)breakthrough times and flooding effects are crucial for optimizing CO_(2)flooding strategies.This study utilized numerical simulations to investigate the effects of hydraulic fractures,permeability,and CO_(2)injection rates on CO_(2)breakthrough times and cumulative oil production.Nonlinear relationships among the respective variables were established,with Sobol method analysis delineating the dominant control factors.The key findings indicate that although hydraulic fracturing shortens CO_(2)breakthrough time,it concurrently enhances cumulative oil production.The orientation of hydraulic fractures emerged as a pivotal factor influencing flooding effectiveness.Furthermore,lower permeability corresponds to lower initial oil production,while higher permeability corresponds to higher initial daily oil production.When reservoir permeability is 1 mD,oil production declines at 1000 days,and at 2 mD,it declines at 700 days.At a surface CO_(2)injection rate of 10,000 m^(3)/d,the daily oil production of a single well is approximately 7.5 m^(3),and this value remains relatively stable over time.The hierarchical order of influence on CO_(2)breakthrough and rapid rise times,from highest to lowest,is permeability,well spacing,CO_(2)injection rate,porosity,and hydraulic fracture conductivity.Similarly,the order of influence on cumulative oil production,from highest to lowest,is well spacing,porosity,permeability,CO_(2)injection rate,and hydraulic fracture conductivity.This paper analyzed the impact of geological and engineering parameters on CO_(2)flooding and oil production and provided insights to optimize CO_(2)injection strategies for enhanced oil recovery.展开更多
Clock difference between the ensemble pulsar timescale(PT)and the International Atomic Time(TAI)PT-TAI derived from the International Pulsar Timing Array(IPTA)data set indicates a very similar variation trend with the...Clock difference between the ensemble pulsar timescale(PT)and the International Atomic Time(TAI)PT-TAI derived from the International Pulsar Timing Array(IPTA)data set indicates a very similar variation trend with the Terrestrial Time TT(BIPMXXXX)-TAI but PT has larger measurement error.In this paper,we discuss the smoothing method of PT using a combined smoothing filter and compare the results with that from other filters.The clock difference sequence between PT-TAI and the first time derivative series of the TT(BIPMXXXX)-TAI can be combined by a combined smoothing filter to yield two smooth curves tied by the constraints assuring that the latter is the derivative of the former.The ensemble pulsar time IPTA2016 with respect to TAI published by G.Hobbs et al.and first time derivative series of the TT(BIPM2017)-TAI with quadratic polynomial terms removed are processed by combined smoothing filter in order to demonstrate the properties of the smoothed results.How to correctly estimate two smoothing coefficients is described and the output results of the combined smoothing filter are analyzed.The results show that the combined smoothing method efficiently removes high frequency noises of two input data series and the smoothed data of the PT-TAI combine long term fractional frequency stability of the pulsar time and frequency accuracy of the terrestrial time.Fractional frequency stability analysis indicates that both short and medium time interval stability of the smoothed PT-TAI is improved while keeping its original long term frequency stability level.The combined smoothing filter is more suitable for smoothing observational pulsar timescale data than any filter that only performs smoothing of a single pulsar time series.The smoothed pulsar time by combined smoothing filter is a pulsar atomic time combined timescale.This kind of combined timescale can also be used as terrestrial time.展开更多
Drawing up of syllabus plays a very important role in directing college English teaching. With the fast developing pace of the situation and the increasing requirements for undergraduates＇ English level, the availabl...Drawing up of syllabus plays a very important role in directing college English teaching. With the fast developing pace of the situation and the increasing requirements for undergraduates＇ English level, the available Syllabus is obviously far from satisfaction. This paper, from six perspectives, expounds the inadequacies and drawbacks of the Syllabus. It points out that college English teaching and the Syllabus need reform and should keep pace with the times.展开更多
Inconsistency is a fundamental problem in simultaneous localization and mapping(SLAM).Previous works from predecessors have studied the inconsistent problem of extended Kalman filter(EKF)SLAM algorithm focusing on the...Inconsistency is a fundamental problem in simultaneous localization and mapping(SLAM).Previous works from predecessors have studied the inconsistent problem of extended Kalman filter(EKF)SLAM algorithm focusing on the linearization errors.In this paper,we studied the inconsistency issue of EKF SLAM in theory based on measurement noise and observation time.In a simplified situation,we deduced some useful theorems of estimated covariance matrix.Then,we made use of them to investigate the inconsistency issue.We showed that the measurement noise and the observation times can drive the EKF SLAM out of consistency.Moreover,we demonstrated the explicit effects of measurement noise and observation times on inconsistency of the EKF SLAM.Our simulation experiments verified the results.展开更多
Objective： To observe the differences in analgesic effect of moxibustion at different intervention times on dysmenorrhea rats and explore its effect mechanism.Methods： Forty-five female Wistar rats were randomly div...Objective： To observe the differences in analgesic effect of moxibustion at different intervention times on dysmenorrhea rats and explore its effect mechanism.Methods： Forty-five female Wistar rats were randomly divided into blank control group（group A）, model group（group B）, pre-moxibustion group（group C）, instant moxibustion group（group D） and pre-instant moxibustion group（group E）,with 9 rats in each group. Cold-damp coagulation and stagnation type dysmenorrhea models were established. In group C,mild moxibustion on ＂Shenque（神阙 CV 8） ＂ and＂Guanyuan（关元 CV 4）＂ was carried out from the time after modeling on the 8 th day for 3 consecutive days. In group D, mild moxibustion was given as the same methods with group C after injection with oxytocin on the 11 th day. In group E, mild moxibustion was given as the same methods from the time after modeling on the 8 th day to that after injection with oxytocin on the 11 th day for 4 consecutive days. The writhing behavior and the changes in levels of ET-1 and NO in uterine tissues of rats with dysmenorrhea in each group were observed.Results： Comparison of the latent period： compared with（4.38 ± 1.06） min in group B,the latent period of rats in group C（9.67 ± 1.32） min,group D（11.78 ± 1.30） min and group E（15.00 ± 1.22） min obviously prolonged（all p 0.01）. Compared with group C, the latent period of group E obviously prolonged（p 0.01）. Compared with group D, the latent period of group E obviously prolonged（p 0.01）.Comparison of the writhing times： compared with（4.38 ± 1.06） in group B,the writhing times of rats in group C（9.67 ± 1.32）,group D（11.78 ± 1.30） and group E（15.00 ± 1.22） reduced（all p 0.01）. Compared with group C,the writhing times of rats in group D and group E reduced（both p 0.01）. Compared with group D, the writhing times in group E reduced（p 0.05）. Comparison of the total writhing score：compared with（4.38 ± 1.06） in group B,the total writhing score of rats in group C（9.67±1.32）,group D（11.78 ± 1.30） and group E（15.00 ± 1.22） decreased（all p 0.01）. Compared with group C,the total writhing score of rats in group D and group E decreased（both p 0.01）. Compared with group D,the total writhing score of rats in group E decreased（p 0.05）. Comparison of ET-1 level： compared with（4.80 ± 0.47） in group A,the ET-1 level in uterine tissues of rats in group B（7.57±0.69） significantly increased（P 0.01）. Compared with group B, the ET-1 level in uterine tissues of rats in group C（6.20 ±0.50）,group D（5.67 ±0.29） and group E（5.16±0.33） obviously decreased（all p 0.01）. Compared with group C, the ET-1 level in uterine tissues of rats in group D and group E obviously decreased（p 0.05, p 0.01）. Compared with group D, the ET-1 level in uterine tissues of rats in group Eobviously decreased（p 0.05）. Comparison of NO level： compared with（6.63±1.83） in group A, the NO level in uterine tissues of rats in group B（1.62 ±0.58） significantly decreased（p 0.01）. Compared with group B, the NO level in uterine tissues of rats in group C（3.60±0.59）,group D（4.77 ±0.67） and group E（5.99±0.63） obviously increased（all p 0.01）. Compared with group C,the NO level in uterine tissues of rats in group Dand group E obviously increased（p 0.05, p 0.01）. Compared with group D, the NO level in uterine tissues of rats in group E obviously increased（p 0.01）.Conclusion： The analgesic effect of mild moxibustion at different intervention times on cold-damp coagulation and stagnation type dysmenorrhea rats was different, which was the most significant in pre-instant moxibustion group. One of the mechanisms of action may be related with the adjustment of abnormal levels of ET-1 and NO.展开更多
[Objective] The aim was to investigate effects of bagging and bag-removing times on quality of applepear. [Method] The seven-year-old applepears were taken as materials to explore effects of bagging and bag-removing t...[Objective] The aim was to investigate effects of bagging and bag-removing times on quality of applepear. [Method] The seven-year-old applepears were taken as materials to explore effects of bagging and bag-removing times on external and internal quality of applepear. [Result] Scientific timing of either bagging or bag removing will improve fruit quality, color expressed by anthocyanin pigments and coloring index, and reduce chlorophyll content, pericarp thickness and fruit dots. [Conclusion] It has determined that the scientific times of applepear bagging and bag removing are 55 d after peak flowering and 13 d prior to harvesting in Fuxin, Liaoning Province.展开更多
In this paper,we discuss on the convergence and approximation of an α times integrated semigroups. The Trotter kato theorems for an α times integrated semigroups are obtained.
As one of the basic inventory cost models, the （Q, τ）inventory cost model of dual suppliers with random procurement lead time is mostly formulated by using the concepts of ＂effective lead time＂ and ＂lead time de...As one of the basic inventory cost models, the （Q, τ）inventory cost model of dual suppliers with random procurement lead time is mostly formulated by using the concepts of ＂effective lead time＂ and ＂lead time demand＂, which may lead to an imprecise inventory cost. Through the real-time statistic of the inventory quantities, this paper considers the precise （Q, τ） inventory cost model of dual supplier procurement by using an infinitesimal dividing method. The traditional modeling method of the inventory cost for dual supplier procurement includes complex procedures. To reduce the complexity effectively, the presented method investigates the statistics properties in real-time of the inventory quantities with the application of the infinitesimal dividing method. It is proved that the optimal holding and shortage costs of dual supplier procurement are less than those of single supplier procurement respectively. With the assumption that both suppliers have the same distribution of lead times, the convexity of the cost function per unit time is proved. So the optimal solution can be easily obtained by applying the classical convex optimization methods. The numerical examples are given to verify the main conclusions.展开更多
文摘In 2024,the world witnessed further transformation and instability,marked by protracted and intensified geopolitical conflicts,repeated attempts to decouple and sever supply chains,and the rapid rise of the Global South.It has become all the more clear where the once-in-a-century transformations are heading.In 2024,China acted on the blueprint drawn up at the Third Plenary Session of the 20th Central Committee of the Communist Party of China(CPC),and made big strides in deepening reform comprehensively.Marking the 75th anniversary of the founding of New China,China carried forward its great cause of national development and pressed ahead with Chinese modernization with vigor and determination.
基金supported by the Quzhou Science and Technology Bureau Project(2023D023,2023D030,2023D002,and2024D028)the Joint Funds of the Zhejiang Provincial Natural Science Foundation of China(LZY23B030002)+3 种基金the Shijiazhuang Shangtai Technology Co.,Ltd.Hebei Provincial Department of Science and Technology(24291101Z)the International Cooperation Projects of Sichuan Provincial Department of Science and Technology(2021YFH0126)the Sichuan Provincial Science and Technology Department's key research project(2023YFG0203)。
文摘Metal foils have emerged as one of the promising materials for anode-free batteries due to their high energy density and scalability in production.The unclear lithium plating/stripping kinetics of metal foil current collectors in anode-free batteries was addressed by using the non-destructive distribution of relaxation times(DRT)analysis to systematically investigate the lithium transport behavior of 14 metal foils and its correlation with electrochemical performance.By integrating energy-dispersive spectro scopy(EDS),cyclic voltammetry(CV),and galvanostatic testing,the exceptional properties of indium(In),tin(Sn),and silver(Ag)were revealed:the Li-In alloying reaction exhibits high reversibility,Li-Sn alloys demonstrate outstanding cycling stability,and the Li-Ag solid-solution mechanism provides an ideal lithium deposition interface on the silver substrate.The DRT separates the polarization internal resistance of lithium ions passing through the SEI layer(R_(sei),τ2)and the polarization internal resistance of lithium ions undergoing charge transfer reaction at the electrolyte/electrode interface(R_(ct),τ3)by decoupling the electrochemical impedance spectroscopy(EIS).For the first time,the correlation betweenτ2,τ3,and the cycle life/Coulombic efficiency of alloy/solid-solution metals was established,while non-alloy metals are not suitable for this method due to differences in lithium deposition mechanisms.This study not only illuminates the structure-property relationship governing the lithium kinetics of metal foil electrodes but also provides a novel non-destructive analytical strategy and theoretical guidance for the rational design of stable anodes in high-energy-density batteries,facilitating the efficient screening and optimization of anode-free battery.
文摘A performer breathes fire during Chinese New Year celebrations at Binondo district,considered the world’s oldest Chinatown,on January 29 in Manila,Philippines.The celebrations,lasting approximately 15 days,were filled with traditional activities such as family gatherings,lion dances,and the exchange of red envelopes,joining the vibrant cultural event observed by Chinese communities worldwide.
基金supported by the Science and Technology Innovation Program of Hunan Province(Grant No.2021RC4026)。
文摘InAs/AlAs superlattice structures have significant potential for application in low-noise avalanche photodetectors.With their performance in practical applications linked to the fundamental physical properties of carrier relaxation time,this study investigated the carrier relaxation times of InAs/AlAs superlattices across various monolayers,temperatures,and carrier concentrations.Our investigation indicated that relaxation times span several tens of picoseconds,confirming that high-quality interfaces do not significantly reduce relaxation times in the way defect states might.Moreover,our study demonstrates that adjustments to the superlattice period can effectively modulate both the bandgap and carrier relaxation times,potentially impacting the performance of avalanche photodiodes by altering the electron-phonon interaction pathways and bandgap width.We established that lower temperatures contribute to an increase in the bandgap and the suppression of high-frequency optical phonon vibrations,thereby lengthening the relaxation times.Additionally,our observations indicate that in InAs/AlAs superlattices,the relaxation time increases as the excitation power increases,owing to the phonon bottleneck effect.These insights into InAs/AlAs superlattice carrier dynamics highlight their applicability in enhancing avalanche photodetectors,and may contribute to the optimized design of superlattices for specific applications.
基金financially supported by the National Natural Science Foundation of China(No.12374207)the Natural Science Foundation of Jiangsu Province(No.BK20233001)supported by the Big Data Computing Center of Southeast University。
文摘We present a comprehensive extension of the integral of first passage times(IFS)method to investigate the adsorption kinetics of polymers with multiple binding sites on planar surfaces.While effective for single-point adsorption,the original IFS method was limited in capturing the complex kinetics of multi-point adsorption due to inadequate reaction coordinates and theoretical frameworks.Our approach introduces a center-of-mass-based reaction coordinate and a generalized kinetic model that accounts for multi-barrier free energy landscapes characteristic of collective polymer diffusion and binding.This theoretical advancement,implemented using the adaptive bias force method for efficient sampling,enables prediction of adsorption kinetics across timescales from nanoseconds to seconds.Our results demonstrate that adsorption behavior is governed by two key factors:the number of binding monomers primarily controls desorption barriers and long-term stability,while the configuration of pre-adsorbed layers significantly modulates both adsorption and desorption rates.Polymers with three or more binding sites exhibit effectively irreversible adsorption due to exponentially increasing desorption barriers,whereas different adsorbed layer configurations lead to distinct equilibrium coverages and kinetic profiles.This extended IFS framework provides critical insights for designing functional surfaces in nanoscale sensing,macromolecular recognition,and tailored polymeric coatings where precise control over adsorption kinetics is essential.
文摘近年来,科研论文的合著现象及其与论文影响力之间的关系受到广泛关注。本文以1997—2013年Financial Times TOP 45商学院国际期刊论文为研究对象,对作者数量与论文被引(高被引还是零被引)之间的关系进行实证研究,从论文影响力方面揭示商学领域是否存在最佳科研合作规模。研究发现:①与单独作者相比,多作者合作对论文总被引频次具有显著的正向影响,而且多作者合作论文成为高被引的概率更高,而成为零被引的概率更低;②作者数量与论文总被引频次之间存在显著的倒U形关系;进一步研究发现,作者数量与高被引论文概率呈倒U形关系,而与零被引论文概率呈正U形关系,且转折点均约为3人,表明商学领域存在使论文成为高被引而避免成为零被引的最佳合作规模;③分时间阶段实证结果表明,基于高被引和零被引的论文最佳合作规模逐步由2~3人增加至3~4人。
基金funded by the Australian Government,Department of Agriculture,Fisheries and Forestry,and the Cotton Research and Development Corporation through the More Profit from Nitrogen project.
文摘Achieving a sustainable cropping system requires the efficient use of resources,particularly nitrogen(N).Nitrogen fertiliser is applied in most irrigated cotton fields to maximise yield potential,but plant fertiliser recovery can be low.Identifying the crucial pathways of fertiliser remobilisation internally within cotton plants will lead to greater awareness of the plants’ability to match the N demands of the developing fruiting matter.This study investigated the fate of N fertiliser when applied to cotton at various dates,with the goal to improve N fertiliser recovery in a modern transgenic cotton cultivar.15N-labelled urea(10 atom%)was applied at multiple times and harvested at four key cotton growth stages(first square,early bolls,cut-out and maturity).Remobilised N was determined as the difference in the proportion of N fertiliser in individual plant components against the fertiliser utilised by the whole plant.The application of fertiliser N at first square resulted in 23%greater fertiliser N recovery at plant maturity compared to fertiliser N applied 100%pre-plant(P<0.001).The improvement was in-part due to higher N derived from the fertiliser(Ndff%)in the cotton seed(3%).Conversely,the Ndff%was higher in the stem(4%)and petioles(1%)when the fertiliser was applied pre-plant.In total,73%of plant N was remobilised to another plant organ,predominantly the seed(67%).Applying N fertiliser post-planting improved N recovery and lint yield compared to applying all fertiliser pre-plant.
基金supported by the China Postdoctoral Science Foundation(No.2024M752803)the National Natural Science Foundation of China(No.52179112)+1 种基金the Open Fund of National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,China(No.PLN2023-02)the Open Fund of Key Laboratory of Deep Geothermal Resources,Ministry of Natural Resources of the People's Republic of China(No.KLDGR2024B01).
文摘Comprehensive studies on CO_(2)breakthrough times and flooding effects are crucial for optimizing CO_(2)flooding strategies.This study utilized numerical simulations to investigate the effects of hydraulic fractures,permeability,and CO_(2)injection rates on CO_(2)breakthrough times and cumulative oil production.Nonlinear relationships among the respective variables were established,with Sobol method analysis delineating the dominant control factors.The key findings indicate that although hydraulic fracturing shortens CO_(2)breakthrough time,it concurrently enhances cumulative oil production.The orientation of hydraulic fractures emerged as a pivotal factor influencing flooding effectiveness.Furthermore,lower permeability corresponds to lower initial oil production,while higher permeability corresponds to higher initial daily oil production.When reservoir permeability is 1 mD,oil production declines at 1000 days,and at 2 mD,it declines at 700 days.At a surface CO_(2)injection rate of 10,000 m^(3)/d,the daily oil production of a single well is approximately 7.5 m^(3),and this value remains relatively stable over time.The hierarchical order of influence on CO_(2)breakthrough and rapid rise times,from highest to lowest,is permeability,well spacing,CO_(2)injection rate,porosity,and hydraulic fracture conductivity.Similarly,the order of influence on cumulative oil production,from highest to lowest,is well spacing,porosity,permeability,CO_(2)injection rate,and hydraulic fracture conductivity.This paper analyzed the impact of geological and engineering parameters on CO_(2)flooding and oil production and provided insights to optimize CO_(2)injection strategies for enhanced oil recovery.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences(grant No.XDA0350502)the National SKA Program of China(grant No.2020SKA0120103)the National Natural Science Foundation of China(NSFC,Grant Nos.U1831130 and 11973046)。
文摘Clock difference between the ensemble pulsar timescale(PT)and the International Atomic Time(TAI)PT-TAI derived from the International Pulsar Timing Array(IPTA)data set indicates a very similar variation trend with the Terrestrial Time TT(BIPMXXXX)-TAI but PT has larger measurement error.In this paper,we discuss the smoothing method of PT using a combined smoothing filter and compare the results with that from other filters.The clock difference sequence between PT-TAI and the first time derivative series of the TT(BIPMXXXX)-TAI can be combined by a combined smoothing filter to yield two smooth curves tied by the constraints assuring that the latter is the derivative of the former.The ensemble pulsar time IPTA2016 with respect to TAI published by G.Hobbs et al.and first time derivative series of the TT(BIPM2017)-TAI with quadratic polynomial terms removed are processed by combined smoothing filter in order to demonstrate the properties of the smoothed results.How to correctly estimate two smoothing coefficients is described and the output results of the combined smoothing filter are analyzed.The results show that the combined smoothing method efficiently removes high frequency noises of two input data series and the smoothed data of the PT-TAI combine long term fractional frequency stability of the pulsar time and frequency accuracy of the terrestrial time.Fractional frequency stability analysis indicates that both short and medium time interval stability of the smoothed PT-TAI is improved while keeping its original long term frequency stability level.The combined smoothing filter is more suitable for smoothing observational pulsar timescale data than any filter that only performs smoothing of a single pulsar time series.The smoothed pulsar time by combined smoothing filter is a pulsar atomic time combined timescale.This kind of combined timescale can also be used as terrestrial time.
文摘Drawing up of syllabus plays a very important role in directing college English teaching. With the fast developing pace of the situation and the increasing requirements for undergraduates＇ English level, the available Syllabus is obviously far from satisfaction. This paper, from six perspectives, expounds the inadequacies and drawbacks of the Syllabus. It points out that college English teaching and the Syllabus need reform and should keep pace with the times.
文摘Inconsistency is a fundamental problem in simultaneous localization and mapping(SLAM).Previous works from predecessors have studied the inconsistent problem of extended Kalman filter(EKF)SLAM algorithm focusing on the linearization errors.In this paper,we studied the inconsistency issue of EKF SLAM in theory based on measurement noise and observation time.In a simplified situation,we deduced some useful theorems of estimated covariance matrix.Then,we made use of them to investigate the inconsistency issue.We showed that the measurement noise and the observation times can drive the EKF SLAM out of consistency.Moreover,we demonstrated the explicit effects of measurement noise and observation times on inconsistency of the EKF SLAM.Our simulation experiments verified the results.
基金Supported by Youth fund project of Hebei Education Department:QN2015027scientific project supported by Administration of Traditional Chinese Medicine of Hebei Province:2015089scientific program supported by Hebei Provincial Science and Technology Department:152777143~~
文摘Objective： To observe the differences in analgesic effect of moxibustion at different intervention times on dysmenorrhea rats and explore its effect mechanism.Methods： Forty-five female Wistar rats were randomly divided into blank control group（group A）, model group（group B）, pre-moxibustion group（group C）, instant moxibustion group（group D） and pre-instant moxibustion group（group E）,with 9 rats in each group. Cold-damp coagulation and stagnation type dysmenorrhea models were established. In group C,mild moxibustion on ＂Shenque（神阙 CV 8） ＂ and＂Guanyuan（关元 CV 4）＂ was carried out from the time after modeling on the 8 th day for 3 consecutive days. In group D, mild moxibustion was given as the same methods with group C after injection with oxytocin on the 11 th day. In group E, mild moxibustion was given as the same methods from the time after modeling on the 8 th day to that after injection with oxytocin on the 11 th day for 4 consecutive days. The writhing behavior and the changes in levels of ET-1 and NO in uterine tissues of rats with dysmenorrhea in each group were observed.Results： Comparison of the latent period： compared with（4.38 ± 1.06） min in group B,the latent period of rats in group C（9.67 ± 1.32） min,group D（11.78 ± 1.30） min and group E（15.00 ± 1.22） min obviously prolonged（all p 0.01）. Compared with group C, the latent period of group E obviously prolonged（p 0.01）. Compared with group D, the latent period of group E obviously prolonged（p 0.01）.Comparison of the writhing times： compared with（4.38 ± 1.06） in group B,the writhing times of rats in group C（9.67 ± 1.32）,group D（11.78 ± 1.30） and group E（15.00 ± 1.22） reduced（all p 0.01）. Compared with group C,the writhing times of rats in group D and group E reduced（both p 0.01）. Compared with group D, the writhing times in group E reduced（p 0.05）. Comparison of the total writhing score：compared with（4.38 ± 1.06） in group B,the total writhing score of rats in group C（9.67±1.32）,group D（11.78 ± 1.30） and group E（15.00 ± 1.22） decreased（all p 0.01）. Compared with group C,the total writhing score of rats in group D and group E decreased（both p 0.01）. Compared with group D,the total writhing score of rats in group E decreased（p 0.05）. Comparison of ET-1 level： compared with（4.80 ± 0.47） in group A,the ET-1 level in uterine tissues of rats in group B（7.57±0.69） significantly increased（P 0.01）. Compared with group B, the ET-1 level in uterine tissues of rats in group C（6.20 ±0.50）,group D（5.67 ±0.29） and group E（5.16±0.33） obviously decreased（all p 0.01）. Compared with group C, the ET-1 level in uterine tissues of rats in group D and group E obviously decreased（p 0.05, p 0.01）. Compared with group D, the ET-1 level in uterine tissues of rats in group Eobviously decreased（p 0.05）. Comparison of NO level： compared with（6.63±1.83） in group A, the NO level in uterine tissues of rats in group B（1.62 ±0.58） significantly decreased（p 0.01）. Compared with group B, the NO level in uterine tissues of rats in group C（3.60±0.59）,group D（4.77 ±0.67） and group E（5.99±0.63） obviously increased（all p 0.01）. Compared with group C,the NO level in uterine tissues of rats in group Dand group E obviously increased（p 0.05, p 0.01）. Compared with group D, the NO level in uterine tissues of rats in group E obviously increased（p 0.01）.Conclusion： The analgesic effect of mild moxibustion at different intervention times on cold-damp coagulation and stagnation type dysmenorrhea rats was different, which was the most significant in pre-instant moxibustion group. One of the mechanisms of action may be related with the adjustment of abnormal levels of ET-1 and NO.
文摘[Objective] The aim was to investigate effects of bagging and bag-removing times on quality of applepear. [Method] The seven-year-old applepears were taken as materials to explore effects of bagging and bag-removing times on external and internal quality of applepear. [Result] Scientific timing of either bagging or bag removing will improve fruit quality, color expressed by anthocyanin pigments and coloring index, and reduce chlorophyll content, pericarp thickness and fruit dots. [Conclusion] It has determined that the scientific times of applepear bagging and bag removing are 55 d after peak flowering and 13 d prior to harvesting in Fuxin, Liaoning Province.
文摘In this paper,we discuss on the convergence and approximation of an α times integrated semigroups. The Trotter kato theorems for an α times integrated semigroups are obtained.
基金supported by the National High Technology Research and Development Program of China(863 Program)(2007AA04Z102)the National Natural Science Foundation of China(6087407160574077).
文摘As one of the basic inventory cost models, the （Q, τ）inventory cost model of dual suppliers with random procurement lead time is mostly formulated by using the concepts of ＂effective lead time＂ and ＂lead time demand＂, which may lead to an imprecise inventory cost. Through the real-time statistic of the inventory quantities, this paper considers the precise （Q, τ） inventory cost model of dual supplier procurement by using an infinitesimal dividing method. The traditional modeling method of the inventory cost for dual supplier procurement includes complex procedures. To reduce the complexity effectively, the presented method investigates the statistics properties in real-time of the inventory quantities with the application of the infinitesimal dividing method. It is proved that the optimal holding and shortage costs of dual supplier procurement are less than those of single supplier procurement respectively. With the assumption that both suppliers have the same distribution of lead times, the convexity of the cost function per unit time is proved. So the optimal solution can be easily obtained by applying the classical convex optimization methods. The numerical examples are given to verify the main conclusions.
