Nitrogen(N)is an essential plant growth nutrient whose coordinated distribution from source to sink organs is crucial for seed development and overall crop yield.We compared high and low N use efficiency(NUE)Brassica ...Nitrogen(N)is an essential plant growth nutrient whose coordinated distribution from source to sink organs is crucial for seed development and overall crop yield.We compared high and low N use efficiency(NUE)Brassica napus(rapeseed)genotypes.Metabonomics and transcriptomics revealed that leaf senescence induced by N deficiency promoted amino acid allocation from older to younger leaves in the high-NUE genotype at the vegetative growth stage.Efficient source to sink remobilization of amino acids elevated the numbers of branches and pods per plant under a N-deficiency treatment during the reproductive stage.A15N tracer experiment confirmed that more amino acids were partitioned into seeds from the silique wall during the pod stage in the high-NUE genotype,owing mainly to variation in genes involved in organic N transport and metabolism.We suggest that the greater amino acid source-to-sink allocation efficiency during various growth stages in the high-NUE genotype resulted in higher yield and NUE under N deficiency.These findings support the hypothesis that strong amino acid remobilization in rapeseed leads to high yield,NUE,and harvest index.展开更多
The central environmental protection inspection (CEPI) system in China is a significant institutional innova‐tion in national environmental governance. The CEPI applies a joint supervision strategy to address salient...The central environmental protection inspection (CEPI) system in China is a significant institutional innova‐tion in national environmental governance. The CEPI applies a joint supervision strategy to address salient en‐vironmental issues and strictly enforce the environmental responsibilities of local governments. This study col‐lects and organizes CEPI inspection reports covering three stages that encompass the first round, the “look back”, and the second round, applying text analysis to obtain sample data and conduct statistical quantifica‐tion of word frequency in inspection reports and identify notable changes. The study explores the allocation of CEPI attention between policy objectives and the intensity of policy instruments. We determine that in con‐junction with public opinion feedback, the CEPI conducts targeted inspections and focuses more on pollutant governance, which has high severity and can be addressed quickly. The CEPI fills the gap of normalized gover‐nance with a campaign-style governance approach. Regarding the intensity of policy measures, the CEPI pri‐marily uses economic incentive policy instruments, supplemented by command-and-control and public guid‐ance approaches, advancing the sustainability of regulatory effectiveness through economic, social, and politi‐cal activities. This study extends knowledge in the field of CEPI policy priorities and implementation, expand‐ing the literature related to outcomes of environmental policy in developing countries.展开更多
^ 15N isotope tracer techniques and ecological modeling were adopted to investigate the fractionation of nitrogen, its uptake and transformation in algae and snail (Bellamya aeruginosa Reeve). Different algal specie...^ 15N isotope tracer techniques and ecological modeling were adopted to investigate the fractionation of nitrogen, its uptake and transformation in algae and snail (Bellamya aeruginosa Reeve). Different algal species were found to differ in their uptake of nitrogen isotopes. Microcystis aeruginisa Ktitz. demonstrated the greatest ^15N accumulation capacity, with the natural variation in isotopic ratio (δ^15N) and the isotope fractionation factor (ε,‰) being the highest among the species investigated. The transformation and utilization of ^15N by snails differed depending on the specific algae consumed (highest for Chlorella pyrenoidosa Chick., lowest for M. aeruginisa). When snails was seeded in the experimental pond, the algae population structure changed significantly, and total algal biomass as well as the concentration of all nitrogen species decreased, causing an increase in water transparency. A model, incorporating several chemical and biological parameters, was developed to predict algal biomass in an aquatic system when snails was present. The data collected during this investigation indicated that the gastropods such as snails could significantly impact biological community and water quality of small water bodies, suggesting a role for biological control of noxious algal blooms associated with eutrophication.展开更多
Elucidation of the CuOx-CeO2 interactions is of great interest and importance in understanding complex CuOx-CeO2 interfacial catalysis in various reactions. In the present work, we have investigated structures and cat...Elucidation of the CuOx-CeO2 interactions is of great interest and importance in understanding complex CuOx-CeO2 interfacial catalysis in various reactions. In the present work, we have investigated structures and catalytic activity in CO oxidation of CuOx species on CeO2 rods, cubes and polyhedra predominantly exposing {110}+{100}, {100} and {111} facets by the incipient wetness impregnation method with the lowest Cu loading of 0.025%. The structural evolution of CuOx species was found to depend on both the Cu loading and the CeO2 morphology. As the Cu loading increases, CuOx species are deposited preferentially on the surface defect of CeO2 and then aggregate and grow, accompanied by the formation of isolated Cu ions, CuOx clusters strongly/weakly interacting with the CeO2, highly dispersed Cu O nanoparticles, and large Cu O nanoparticles. The isolated Cu^+ species and CuOx clusters weakly interacting with the CeO2 were observed mainly on the O-terminated CeO2{100} facets. Meanwhile, more Cu(I) species are stabilized during CO reduction processes in CuOx/c-CeO2 catalysts than in CuOx/r-CeO2 and CuOx/p-CeO2 catalysts. The catalytic activities of various CuOx/CeO2 catalysts in CO oxidation vary with both the CuOx species and the CeO2 morphology. These results comprehensively elucidate the CuOx-CeO2 interactions and exemplify their morphology-dependence.展开更多
The performance of an iodine radio ion thruster with a 4 cm diameter(IRIT4)was studied experimentally in this paper.Regulation of the mass flow rates of the iodine propellant is achieved by using a temperature control...The performance of an iodine radio ion thruster with a 4 cm diameter(IRIT4)was studied experimentally in this paper.Regulation of the mass flow rates of the iodine propellant is achieved by using a temperature control method of the iodine reservoir.Performance of the thruster using iodine as propellants is obtained at different total thruster powers of 40.6–128.8 W,different grid voltages of 1000–1800 V and the iodine flow rate of 100μgs^(-1).Results show that thrust and specific impulse increase approximately linearly with the increasing total thruster power and the screen grid voltage.The thrust of 2.32 mN and the specific impulse of 2361 s are obtained at the nominal total thruster power of 95.8 W and the screen grid voltage of 1800 V.It is also indicated that performance of the iodine propellant is comparable to that of the xenon propellant;and a difference between them is that the iodine thrust is slightly higher than xenon when the total thruster power is more than 62 W.At the nominal 95.8 W total thruster power,the thrust values of them are 2.32 m N and 2.15 mN respectively,and the thrust-to-power ratios of them are 24.2 mN kW^(-1)and 23.5 mN kW^(-1),respectively.展开更多
Grain weight is one of themost important determinants of grain yield in rice.In this study,QTL analysis for grain weight,grain length,and grainwidthwas performed using populations derived from crosses between major pa...Grain weight is one of themost important determinants of grain yield in rice.In this study,QTL analysis for grain weight,grain length,and grainwidthwas performed using populations derived from crosses between major parental lines of three-line indica hybrid rice.A total of 27 QTL for grain weight were detected using three recombinant inbred line populations derived from the crosses Teqing/IRBB lines,Zhenshan 97/Milyang 46,and Xieqingzao/Milyang 46.Of these,10 were found in only a single population and the other 17 in two or all three populations.Nine of the 17 common QTL were located in regions where no QTL associated with grain weight have been cloned and onewas selected for fine-mapping.Eight populations segregating in an isogenic background were derived from one F7 residual heterozygote of Teqing/IRBB52.The target QTL,qTGW10-20.8 controlling grain weight,grain length,and grain width,was localized to a 70.7-kb region flanked by InDel markers Te20811 and Te20882 on the long arm of chromosome 10.The QTL region contains seven annotated genes,ofwhich six encode proteins with known functional domains and one encodes a hypothetical protein.One of the genes,Os10g0536100 encoding the MIKC-type MADS-box protein OsMADS56,is the most likely candidate for qTGW10-20.8.These results provide a basis for cloning qTGW10-20.8,which has an important contribution to grain weight variation in rice.展开更多
As a consequence of industrial development,soil Cd pollution leads to crop contamination by Cd,posing a threat to food safety and human health.Excessive accumulation of Cd in plants also inhibits their growth via oxid...As a consequence of industrial development,soil Cd pollution leads to crop contamination by Cd,posing a threat to food safety and human health.Excessive accumulation of Cd in plants also inhibits their growth via oxidative stress damage to their photosynthetic systems.Through evolutionary selection,plants have developed a set of efficient strategies to respond to Cd in their environments.These include the accumulation and detoxification of heavy metals.Cd is absorbed by plant roots through the apoplastic and symplastic pathways and then translocated to plant shoots via xylem loading,long-distance transport,and phloem redistribution.Simultaneously,plants initiate a series of mechanisms to reduce Cd toxicity,including cell wall adsorption,cytoplasmic chelation,and vacuolar sequestration.This review summarizes current knowledge of Cd accumulation and detoxification in plants.展开更多
Au nanostructures were prepared on uniform Cu2O octahedra and rhombic dodecahedra via the galvanic replacement reaction between HAuCl 4 and Cu2O. The compositions and structures were studied by Scanning Electron Micro...Au nanostructures were prepared on uniform Cu2O octahedra and rhombic dodecahedra via the galvanic replacement reaction between HAuCl 4 and Cu2O. The compositions and structures were studied by Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), High-Resolution Transmission Electron Microscope (HRTEM), X-Ray Diffraction (XRD), X-Ray Absorption Spectroscopy (XAS), X-ray Photoelectron Spectroscopy (XPS) and in-situ DRIFTS spectroscopy of CO adsorption. Different from the formation of Au-Cu alloys on Cu2O cubes by the galvanic replacement reaction (ChemNanoMat 2 (2016) 861-865), metallic Au particles and positively-charged Au clusters form on Cu2O octahedra and rhombic dodecahedra at very small Au loadings and only metallic Au particles form at large Au loadings. Metallic Au particles on Cu2O octahedra and rhombic dodecahedra are more active in catalyzing the liquid phase aerobic oxidation reaction of benzyl alcohol than positively-charged Au clusters. These results demonstrate an obvious morphology effect of Cu2O nanocrystals on the liquid-solid interfacial reactions and prove oxide morphology as an effective strategy to tune the surface reactivity and catalytic performance. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.展开更多
This paper reports the ignition performance of the iodine-fueled radio frequency(RF)ion thruster(IRIT)at different anode temperaturesT_(a0).The experimental results show that the anode temperature plays important role...This paper reports the ignition performance of the iodine-fueled radio frequency(RF)ion thruster(IRIT)at different anode temperaturesT_(a0).The experimental results show that the anode temperature plays important role on the ignition process of the IRIT.There were two characteristic temperatures related to the anode:the minimum ignition temperatureT_(i0)and the stable ignition temperatureT_(is),which were much lower than the pipeline temperature and the storage tank temperature.AtT_(a0)<T_(i0),it failed to discharge.WhenT_(i0)≤T_(a0)<T_(is),it was ignited with dramatical oscillations.AtT_(a0)≥T_(is),the discharge was stable in a large anode temperature range.The analysis showed that the different discharge phenomena at different anode temperatures were attributed to the change of iodine flow rate during the process of the iodine deposition-clogging and sublimation-clearing inside the thruster.The research helps improve the preheating design of the iodine-fueled electric thruster.展开更多
Identification of quantitative trait loci(QTL) having small effects on heading date(HD) is important for fine-tuning flowering time in rice(Oryza sativa L.). In this study, minor-effect QTL for HD were identified usin...Identification of quantitative trait loci(QTL) having small effects on heading date(HD) is important for fine-tuning flowering time in rice(Oryza sativa L.). In this study, minor-effect QTL for HD were identified using five segregating rice populations, including a recombinant inbred line population derived from crosses between indica cultivar Teqing and near isogenic lines of IR24,and four populations derived from residual heterozygotes identified in the original population.HD data from these populations were obtained in multiple years or at two locations with different photoperiods. A total of 11 QTL were detected; they had small additive effects ranging from 0.21 to1.63 days. The QTL were all detected in different populations, locations and/or years, having consistent allelic effects across experiments and a stable magnitude across years at the same location. These QTL, and other minor-effect QTL that have been cloned or fine-mapped, generally do not have strong photoperiod sensitivity, and thus can be used in a wide range of ecogeographical conditions. Seven of the 11 QTL were different from those that have been cloned or fine-mapped, providing new candidates for gene cloning and marker-assisted breeding. Allelic effects of QTL corresponding to those that had been cloned or fine-mapped, were much smaller in this study than previously reported. The results supported the assumption that qualitative and quantitative genes may be different alleles at the same loci, suggesting that it may be promising to identify minor-effect QTL from major heading date genes/QTL that have been cloned.展开更多
A new knowledge measure with parameter of intuitionistic fuzzy sets (IFSs) is presented based on the membership degree and the non-membership degree of IFSs, which complies with the extended form of Szmidt-Kacprzyk ax...A new knowledge measure with parameter of intuitionistic fuzzy sets (IFSs) is presented based on the membership degree and the non-membership degree of IFSs, which complies with the extended form of Szmidt-Kacprzyk axioms for intuitionistic fuzzy entropy. And a sufficient and necessary condition of order property in the Szmidt-Kacprzyk axioms is discussed. Additionally, some numerical examples are given to illustrate the applications of the proposed knowledge measure and some conventional entropies and knowledge measures of IFSs. The experimental results show that the results of the parametric model proposed in this paper are more accurate than those of most of the classic models.展开更多
Field experiments were conducted during 2008-2010 to investigate the ef- fects of NPK fertilization on seed yield and economic benefit of a new hybrid cultivar of winter oilseed rape (Brassica napus L.) - Xiangzayou...Field experiments were conducted during 2008-2010 to investigate the ef- fects of NPK fertilization on seed yield and economic benefit of a new hybrid cultivar of winter oilseed rape (Brassica napus L.) - Xiangzayou763, and to determine the optimum NPK ratio and dose in Hunan, China. The results showed that NPK ratio (1:0.50:0.50) with 180 kg/hm2 N, 90 kg/hm2 P2O5 and 90 kg/hm2 K20 was the optimum combination for the highest seed yield (2 231.13 kg/hm2) and economic benefit (9 816.97 Yuan/hm2), of which 1 641.23 Yuan/hm2 being set for fertilizer in- vestment (VCR=4.11). Besides, the effects of N, P and K fertilizers on seed yield and oil production of winter oilseed rape were not identical. N had the greatest ef- fect on plant growth of winter oilseed rape, followed by P and K. Total leaf number, green leaf number, leaf length and width, rhizome diameter, branch number, dry weight per plant and other agronomic characters in high N treatments were higher than those in low N treatments. By correlation and path analysis of yield components, the contribution rate to seed yield was found: effective silique number per plant〉seed number per silique〉l 000-seed weight.展开更多
Fencing is the most common land-management practice to protect grassland degradation from livestock overgrazing on the Tibetan Plateau. However, it is unclear whether fencing reduces CO_2, CH_4, and N_2O emission. Her...Fencing is the most common land-management practice to protect grassland degradation from livestock overgrazing on the Tibetan Plateau. However, it is unclear whether fencing reduces CO_2, CH_4, and N_2O emission. Here, we selected four vegetation types of alpine meadow(graminoid, shrub, forb, and sparse vegetation) to determine fencing effects on ecosystem respiration(Re), CH_4, and N_2O fluxes during the growing season. Despite increased average monthly ecosystem respiration(Re) for fenced graminoid vegetation at the end of the growing season, there was no significant difference between grazing and fencing across all vegetation types. Fencing significantly reduced average CH_4 uptake by about 50% in 2008 only for forb vegetation and increased average N_2O release for graminoid vegetation by 38% and 48% in 2008 and 2009,respectively. Temperature, moisture, total organic carbon, C/N, nitrate, ammonia, and/or bulk density of soil, as well as above-and belowground biomass, explained 19%~71% and 6%~33% of variation in daily and average Re and CH_4 fluxes across all vegetation types, while soil-bulk density explained 27% of variation in average N_2O fluxes. Stepwise regression showed that soil temperature and soil moisture controlled average Re, while soil moisture and bulk density controlled average CH_4 fluxes. These results indicate that abiotic factors control Re, CH_4, and N_2O fluxes; and grazing exclusion has little effect on reducing their emission—implying that climatic change rather than grazing may have a more important influence on the budgets of Re and CH_4 for the Tibetan alpine meadow during the growing season.展开更多
Aim: To explore an accurate method to calculate acetabular cup anteversion after total hip arthroplasty. Method: 1) A 3D coordinate system was established with the center of the hip joint rotation center base as coord...Aim: To explore an accurate method to calculate acetabular cup anteversion after total hip arthroplasty. Method: 1) A 3D coordinate system was established with the center of the hip joint rotation center base as coordinate center. The acetabular exit plane and Pettersson formula acetabular anteversion and Riten Pradhan formula acetabular anteversion and acetabular true anteversion were drawn;2) Determine the mathematical expression of Pettersson formula acetabular anteversion α and Riten Pradhan formula acetabular anteversion β in the coordinate system. The true acetabular anteversion is projection angle of Pettersson formula acetabular anteversion α on cross-section in the presence of acetabular abduction δ, determining mathematical expression of the acetabular anteversion θ by trigonometric functions. Results: Real acetabular cup anteversion θ = arctg (tgβ/cosδ). Conclusion: The true acetabular cup anteversion and Pettersson formula anteversion and Riten Pradhan for mula anteversion were quite different. The difference was increased with the acetabular cup abduction angle increased. The formula was simple and accurate and worthy of clinical reference.展开更多
[Objectives]To find a sustainable production model for potato at low latitude plateau in winter in Yunnan Province.[Methods]Xuanshu 2 potato variety was tested in prefectures of Yunnan Province.Soil covering experimen...[Objectives]To find a sustainable production model for potato at low latitude plateau in winter in Yunnan Province.[Methods]Xuanshu 2 potato variety was tested in prefectures of Yunnan Province.Soil covering experiment was conducted in two trials(open field experiment and green house potted experiment).Impacts of three cultivation factors were analyzed:(i)three cultivation models(T1,T2 and T3),(ii)planting density(T1,T2 and T3),(iii)soil covering(T1,T2,T3,T4)on plant growth,and yield production.[Results]The soil moisture content,temperature,roots growth,stems development,leaf area index,and number-weight of tubers per plant and per plot(g)have significantly increased with commercial yield average of 45 t/ha.[Conclusions]The combination of this method with modern agriculture mechanization should be further popularized and applied in large scale planting in regions with climatic conditions similar winter season in Yunnan Province,so as to make contribution to the satisfaction of the world population potato consumption.展开更多
[Objectives]The paper was to understand the species and pathogenicity of the pathogen causing potato early blight in winter.[Methods]The occurrence of potato early blight was investigated in 5 winter potato growing ar...[Objectives]The paper was to understand the species and pathogenicity of the pathogen causing potato early blight in winter.[Methods]The occurrence of potato early blight was investigated in 5 winter potato growing areas in Yunnan Province.The disease samples were collected from two locations(Zhutang Village and Zhanai Village,Pu'er City)where the occurrence of early blight was severe.The pathogen was isolated and purified in laboratory and identified by morphological characteristics and phylogenetic analysis of ITS gene sequence.And it was further verified via re-inoculation by Koch's rules.The growth characteristics and pathogenicity of isolates in different seasons were analyzed with 4 strains of Alternaria isolated in spring(EYZ,EYAX,TA1 and TAC)as controls.[Results]Early blight occurred in varying degrees in the 5 winter potato growing areas,and the incidence of early blight was up to 100%in some plots in Lancang County,Pu'er City.A total of 35 strains of Alternaria were isolated from plots with high incidence,which were divided into two types according to colony morphology.The first type was round colonies with smooth edges and gray white fronts,and the second type was round colonies with rough edges and gray black fronts.Three strains LC1,LC2,LC3 of the first type and two strains ZT3 and ZT8 of the second type were selected and identified as Alternaria alternata through morphological and molecular identification.Re-inoculation test further confirmed that the pathogen was A.alternata.Meantime,it was found that the growth rate of colonies isolated in winter was relatively slow,and there was no significant difference between the pathogenicity of LC1 and TA1,but the pathogenicity of strains isolated in winter was generally higher than that isolated in spring.[Conclusions]It is confirmed that the pathogen causing potato early blight in winter is A.alternata in Yunnan Province.The results will lay a foundation for the research of pathogenesis,occurrence regularity and disease control of A.alternata in winter potato.展开更多
Combining with the third plenary session of the 17th "the central committee of the communist party of China on promoting rural reform and development of certain major issue decision" and the eighteenth big clear adh...Combining with the third plenary session of the 17th "the central committee of the communist party of China on promoting rural reform and development of certain major issue decision" and the eighteenth big clear adherence to and improve the basic rural operation system and to protect farmer' s right to the contracted management of land, the land and collective income distribution, the resolution of collective economic power, this paper discusses the main content of deepening reform of China' s basic rural operation system. It elaborates we must adhere to stabilize and improve the rural basic management systems, give farmers more fully right to protect the land, develop rural land contract management rights transfer, and promote agricultural innovation and industrial organization.展开更多
With the rapid development of China' s tourism industry, the country in various regional economy hotels has sprung up everywhere. Economical hotels affected due to low prices of factors, more and more pro-consumer ga...With the rapid development of China' s tourism industry, the country in various regional economy hotels has sprung up everywhere. Economical hotels affected due to low prices of factors, more and more pro-consumer gaze. Customers source a large part of budget hotels are from users, how to promote their hotel through the Internet is a problem that must be considered by the economy hotel, the paper through the study of economy hotel email marketing strategy wants to Economical hotels certain significance.展开更多
Dark matter(DM)is a major constituent of the Universe.However,no definite evidence of DM particles(denoted as“χ”)has been found in DM direct detection(DD)experiments to date.There is a novel concept of detectingχf...Dark matter(DM)is a major constituent of the Universe.However,no definite evidence of DM particles(denoted as“χ”)has been found in DM direct detection(DD)experiments to date.There is a novel concept of detectingχfrom evaporating primordial black holes(PBHs).We search forχemitted from PBHs by investigating their interaction with target electrons.The examined PBH masses range from 1×10^(15)to 7×10^(16)g under the current limits of PBH abundance fPBH.Using 205.4 kg·day data obtained from the CDEX-10 experiment conducted in the China Jinping Underground Laboratory,we exclude theχ-electron(χ-e)elastic-scattering cross sectionσ_(χe)~5×10^(-29)cm^(2)forχwith a mass■keV from our results.With the higher radiation background but lower energy threshold(160 eV),CDEX-10 fills a part of the gap in the previous work.If(m_(χ),σ_(χe))can be determined in the future,DD experiments are expected to impose strong constraints on fPBHfor large MPBHs.展开更多
Mg-based alloys are regarded as highly promising materials for hydrogen storage.Despite significant improvements of the properties for Mg-based alloys,challenges such as slow hydrogen absorption/desorption kinetics an...Mg-based alloys are regarded as highly promising materials for hydrogen storage.Despite significant improvements of the properties for Mg-based alloys,challenges such as slow hydrogen absorption/desorption kinetics and high thermodynamic stability continue to limit their practical application.In this study,to assess hydrogen storage alloys with enhanced properties,incorporating both internal microstructure modulation through the preparation of amorphous/nanocrystalline structures and surface property enhancement with the addition of Cu and carbon nanotubes(CNTs),the kinetic properties of activation and hydrogenation,thermodynamic properties,and dehydrogenation kinetics are tested.The results reveal a complementary interaction between the added Cu and CNTs,contributing to the superior hydrogen storage performance observed in sample 7A-2Cu-1CNTs with an amorphous/nanocrystalline structure compared to the other experimental samples.Additionally,the samples are fully activated after the initial hydrogen absorption and desorption cycle,demonstrating outstanding hydrogenation kinetics under both high and low temperature experimental conditions.Particularly noteworthy is that the hydrogen absorption exceeds 1.8 wt.% within one hour at 333 K.Furthermore,the activation energy for dehydrogenation is decreased to 64.71 kJ·mol^(–1).This research may offer novel insights for the design of new-type Mg-based hydrogen storage alloys,which possess milder conditions for hydrogen absorption and desorption.展开更多
基金supported by the National Natural Science Foundation of China(U21A20236,32072664)Natural Science Foundation of Hunan Province(2021JJ0004)China Agriculture Research System,and the Hunan Postgraduate Scientific Research Innovation Project(CX20190505)。
文摘Nitrogen(N)is an essential plant growth nutrient whose coordinated distribution from source to sink organs is crucial for seed development and overall crop yield.We compared high and low N use efficiency(NUE)Brassica napus(rapeseed)genotypes.Metabonomics and transcriptomics revealed that leaf senescence induced by N deficiency promoted amino acid allocation from older to younger leaves in the high-NUE genotype at the vegetative growth stage.Efficient source to sink remobilization of amino acids elevated the numbers of branches and pods per plant under a N-deficiency treatment during the reproductive stage.A15N tracer experiment confirmed that more amino acids were partitioned into seeds from the silique wall during the pod stage in the high-NUE genotype,owing mainly to variation in genes involved in organic N transport and metabolism.We suggest that the greater amino acid source-to-sink allocation efficiency during various growth stages in the high-NUE genotype resulted in higher yield and NUE under N deficiency.These findings support the hypothesis that strong amino acid remobilization in rapeseed leads to high yield,NUE,and harvest index.
基金supported by National Natural Science Foundation of China[Grant No.72304124]Spring Sunshine Collaborative Re‐search Project of the Ministry of Education in China[Grant No.202201660]+2 种基金Youth Project of Gansu Natural Science Foundation[Grant No.22JR5RA542]General Project of Gansu Philosophy and Social Science Foundation[Grant No.2022YB014]Fundamental Re‐search Funds for the Central Universities[Grant No.2023lzdxjb‐kyzx008].
文摘The central environmental protection inspection (CEPI) system in China is a significant institutional innova‐tion in national environmental governance. The CEPI applies a joint supervision strategy to address salient en‐vironmental issues and strictly enforce the environmental responsibilities of local governments. This study col‐lects and organizes CEPI inspection reports covering three stages that encompass the first round, the “look back”, and the second round, applying text analysis to obtain sample data and conduct statistical quantifica‐tion of word frequency in inspection reports and identify notable changes. The study explores the allocation of CEPI attention between policy objectives and the intensity of policy instruments. We determine that in con‐junction with public opinion feedback, the CEPI conducts targeted inspections and focuses more on pollutant governance, which has high severity and can be addressed quickly. The CEPI fills the gap of normalized gover‐nance with a campaign-style governance approach. Regarding the intensity of policy measures, the CEPI pri‐marily uses economic incentive policy instruments, supplemented by command-and-control and public guid‐ance approaches, advancing the sustainability of regulatory effectiveness through economic, social, and politi‐cal activities. This study extends knowledge in the field of CEPI policy priorities and implementation, expand‐ing the literature related to outcomes of environmental policy in developing countries.
基金supported by the National Natural Science Foundation of China (No.30870452)the National Chaohu Lake Special Project of China (No.2008ZX07103-005)
文摘^ 15N isotope tracer techniques and ecological modeling were adopted to investigate the fractionation of nitrogen, its uptake and transformation in algae and snail (Bellamya aeruginosa Reeve). Different algal species were found to differ in their uptake of nitrogen isotopes. Microcystis aeruginisa Ktitz. demonstrated the greatest ^15N accumulation capacity, with the natural variation in isotopic ratio (δ^15N) and the isotope fractionation factor (ε,‰) being the highest among the species investigated. The transformation and utilization of ^15N by snails differed depending on the specific algae consumed (highest for Chlorella pyrenoidosa Chick., lowest for M. aeruginisa). When snails was seeded in the experimental pond, the algae population structure changed significantly, and total algal biomass as well as the concentration of all nitrogen species decreased, causing an increase in water transparency. A model, incorporating several chemical and biological parameters, was developed to predict algal biomass in an aquatic system when snails was present. The data collected during this investigation indicated that the gastropods such as snails could significantly impact biological community and water quality of small water bodies, suggesting a role for biological control of noxious algal blooms associated with eutrophication.
文摘Elucidation of the CuOx-CeO2 interactions is of great interest and importance in understanding complex CuOx-CeO2 interfacial catalysis in various reactions. In the present work, we have investigated structures and catalytic activity in CO oxidation of CuOx species on CeO2 rods, cubes and polyhedra predominantly exposing {110}+{100}, {100} and {111} facets by the incipient wetness impregnation method with the lowest Cu loading of 0.025%. The structural evolution of CuOx species was found to depend on both the Cu loading and the CeO2 morphology. As the Cu loading increases, CuOx species are deposited preferentially on the surface defect of CeO2 and then aggregate and grow, accompanied by the formation of isolated Cu ions, CuOx clusters strongly/weakly interacting with the CeO2, highly dispersed Cu O nanoparticles, and large Cu O nanoparticles. The isolated Cu^+ species and CuOx clusters weakly interacting with the CeO2 were observed mainly on the O-terminated CeO2{100} facets. Meanwhile, more Cu(I) species are stabilized during CO reduction processes in CuOx/c-CeO2 catalysts than in CuOx/r-CeO2 and CuOx/p-CeO2 catalysts. The catalytic activities of various CuOx/CeO2 catalysts in CO oxidation vary with both the CuOx species and the CeO2 morphology. These results comprehensively elucidate the CuOx-CeO2 interactions and exemplify their morphology-dependence.
基金financial support from National Natural Science Foundation of China(No.11805265)Key Laboratory of Micro-Satellites,Chinese Academy of Sciences(No.KFKT201903)。
文摘The performance of an iodine radio ion thruster with a 4 cm diameter(IRIT4)was studied experimentally in this paper.Regulation of the mass flow rates of the iodine propellant is achieved by using a temperature control method of the iodine reservoir.Performance of the thruster using iodine as propellants is obtained at different total thruster powers of 40.6–128.8 W,different grid voltages of 1000–1800 V and the iodine flow rate of 100μgs^(-1).Results show that thrust and specific impulse increase approximately linearly with the increasing total thruster power and the screen grid voltage.The thrust of 2.32 mN and the specific impulse of 2361 s are obtained at the nominal total thruster power of 95.8 W and the screen grid voltage of 1800 V.It is also indicated that performance of the iodine propellant is comparable to that of the xenon propellant;and a difference between them is that the iodine thrust is slightly higher than xenon when the total thruster power is more than 62 W.At the nominal 95.8 W total thruster power,the thrust values of them are 2.32 m N and 2.15 mN respectively,and the thrust-to-power ratios of them are 24.2 mN kW^(-1)and 23.5 mN kW^(-1),respectively.
基金supported by the National Key Research and Development Program of China (2016YFD0101104)the National Natural Science Foundation of China (31521064)project of the China National Rice Research Institute (2017RG001-2)
文摘Grain weight is one of themost important determinants of grain yield in rice.In this study,QTL analysis for grain weight,grain length,and grainwidthwas performed using populations derived from crosses between major parental lines of three-line indica hybrid rice.A total of 27 QTL for grain weight were detected using three recombinant inbred line populations derived from the crosses Teqing/IRBB lines,Zhenshan 97/Milyang 46,and Xieqingzao/Milyang 46.Of these,10 were found in only a single population and the other 17 in two or all three populations.Nine of the 17 common QTL were located in regions where no QTL associated with grain weight have been cloned and onewas selected for fine-mapping.Eight populations segregating in an isogenic background were derived from one F7 residual heterozygote of Teqing/IRBB52.The target QTL,qTGW10-20.8 controlling grain weight,grain length,and grain width,was localized to a 70.7-kb region flanked by InDel markers Te20811 and Te20882 on the long arm of chromosome 10.The QTL region contains seven annotated genes,ofwhich six encode proteins with known functional domains and one encodes a hypothetical protein.One of the genes,Os10g0536100 encoding the MIKC-type MADS-box protein OsMADS56,is the most likely candidate for qTGW10-20.8.These results provide a basis for cloning qTGW10-20.8,which has an important contribution to grain weight variation in rice.
基金financially supported by the Province Key R&D Program of Hunan(2018NK1010)the National Natural Science Foundation of China(31800202)+1 种基金the National Oilseed Rape Production Technology System of Chinathe Natural Science Foundation of Hunan Agricultural University(19QN38)。
文摘As a consequence of industrial development,soil Cd pollution leads to crop contamination by Cd,posing a threat to food safety and human health.Excessive accumulation of Cd in plants also inhibits their growth via oxidative stress damage to their photosynthetic systems.Through evolutionary selection,plants have developed a set of efficient strategies to respond to Cd in their environments.These include the accumulation and detoxification of heavy metals.Cd is absorbed by plant roots through the apoplastic and symplastic pathways and then translocated to plant shoots via xylem loading,long-distance transport,and phloem redistribution.Simultaneously,plants initiate a series of mechanisms to reduce Cd toxicity,including cell wall adsorption,cytoplasmic chelation,and vacuolar sequestration.This review summarizes current knowledge of Cd accumulation and detoxification in plants.
基金supported by the National Basic Research Program of China(2013CB933104)the National Natural Science Foundation of China(21525313,21173204,21373192,U1332113)+1 种基金MOE Fundamental Research Funds for the Central Universities(WK2060030017)Collaborative Innovation Center of Suzhou Nano Science and Technology
文摘Au nanostructures were prepared on uniform Cu2O octahedra and rhombic dodecahedra via the galvanic replacement reaction between HAuCl 4 and Cu2O. The compositions and structures were studied by Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), High-Resolution Transmission Electron Microscope (HRTEM), X-Ray Diffraction (XRD), X-Ray Absorption Spectroscopy (XAS), X-ray Photoelectron Spectroscopy (XPS) and in-situ DRIFTS spectroscopy of CO adsorption. Different from the formation of Au-Cu alloys on Cu2O cubes by the galvanic replacement reaction (ChemNanoMat 2 (2016) 861-865), metallic Au particles and positively-charged Au clusters form on Cu2O octahedra and rhombic dodecahedra at very small Au loadings and only metallic Au particles form at large Au loadings. Metallic Au particles on Cu2O octahedra and rhombic dodecahedra are more active in catalyzing the liquid phase aerobic oxidation reaction of benzyl alcohol than positively-charged Au clusters. These results demonstrate an obvious morphology effect of Cu2O nanocrystals on the liquid-solid interfacial reactions and prove oxide morphology as an effective strategy to tune the surface reactivity and catalytic performance. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.
基金financial support from National Natural Science Foundation of China(No.11805265)Key Laboratory of Micro-Satellites,Chinese Academy of Sciences(No.KFKT201903)is gratefully acknowledged。
文摘This paper reports the ignition performance of the iodine-fueled radio frequency(RF)ion thruster(IRIT)at different anode temperaturesT_(a0).The experimental results show that the anode temperature plays important role on the ignition process of the IRIT.There were two characteristic temperatures related to the anode:the minimum ignition temperatureT_(i0)and the stable ignition temperatureT_(is),which were much lower than the pipeline temperature and the storage tank temperature.AtT_(a0)<T_(i0),it failed to discharge.WhenT_(i0)≤T_(a0)<T_(is),it was ignited with dramatical oscillations.AtT_(a0)≥T_(is),the discharge was stable in a large anode temperature range.The analysis showed that the different discharge phenomena at different anode temperatures were attributed to the change of iodine flow rate during the process of the iodine deposition-clogging and sublimation-clearing inside the thruster.The research helps improve the preheating design of the iodine-fueled electric thruster.
基金supported by the National Key Research and Development Program of China (2017YFD0100305)National Natural Science Foundation of China (31521064)a project of the China National Rice Research Institute (2014RG003-1)
文摘Identification of quantitative trait loci(QTL) having small effects on heading date(HD) is important for fine-tuning flowering time in rice(Oryza sativa L.). In this study, minor-effect QTL for HD were identified using five segregating rice populations, including a recombinant inbred line population derived from crosses between indica cultivar Teqing and near isogenic lines of IR24,and four populations derived from residual heterozygotes identified in the original population.HD data from these populations were obtained in multiple years or at two locations with different photoperiods. A total of 11 QTL were detected; they had small additive effects ranging from 0.21 to1.63 days. The QTL were all detected in different populations, locations and/or years, having consistent allelic effects across experiments and a stable magnitude across years at the same location. These QTL, and other minor-effect QTL that have been cloned or fine-mapped, generally do not have strong photoperiod sensitivity, and thus can be used in a wide range of ecogeographical conditions. Seven of the 11 QTL were different from those that have been cloned or fine-mapped, providing new candidates for gene cloning and marker-assisted breeding. Allelic effects of QTL corresponding to those that had been cloned or fine-mapped, were much smaller in this study than previously reported. The results supported the assumption that qualitative and quantitative genes may be different alleles at the same loci, suggesting that it may be promising to identify minor-effect QTL from major heading date genes/QTL that have been cloned.
文摘A new knowledge measure with parameter of intuitionistic fuzzy sets (IFSs) is presented based on the membership degree and the non-membership degree of IFSs, which complies with the extended form of Szmidt-Kacprzyk axioms for intuitionistic fuzzy entropy. And a sufficient and necessary condition of order property in the Szmidt-Kacprzyk axioms is discussed. Additionally, some numerical examples are given to illustrate the applications of the proposed knowledge measure and some conventional entropies and knowledge measures of IFSs. The experimental results show that the results of the parametric model proposed in this paper are more accurate than those of most of the classic models.
基金Supported by the Youth Fund of Orient Science and Technology College,Hunan Agricultural University(14QNZ09)Cultivation Physiology Station of National Technical System in Rape Industrial,National Key Technology Support Program(2012BAD15B04,2010BAD01B01)+1 种基金Special Fund of Government in Hunan Province,National Natural Science Foundation of China(31071851,31101596,3132130)Open Fund Project of Innovation Platform in Colleges and Universities of Hunan Province(12K064)
文摘Field experiments were conducted during 2008-2010 to investigate the ef- fects of NPK fertilization on seed yield and economic benefit of a new hybrid cultivar of winter oilseed rape (Brassica napus L.) - Xiangzayou763, and to determine the optimum NPK ratio and dose in Hunan, China. The results showed that NPK ratio (1:0.50:0.50) with 180 kg/hm2 N, 90 kg/hm2 P2O5 and 90 kg/hm2 K20 was the optimum combination for the highest seed yield (2 231.13 kg/hm2) and economic benefit (9 816.97 Yuan/hm2), of which 1 641.23 Yuan/hm2 being set for fertilizer in- vestment (VCR=4.11). Besides, the effects of N, P and K fertilizers on seed yield and oil production of winter oilseed rape were not identical. N had the greatest ef- fect on plant growth of winter oilseed rape, followed by P and K. Total leaf number, green leaf number, leaf length and width, rhizome diameter, branch number, dry weight per plant and other agronomic characters in high N treatments were higher than those in low N treatments. By correlation and path analysis of yield components, the contribution rate to seed yield was found: effective silique number per plant〉seed number per silique〉l 000-seed weight.
基金supported by the Natural Science Foundation Committee of China(41230750 and 41101081)Key Program of the Chinese Academy of Sciences(KFZD-SW-312)the"National Key Research and Development Program of China"(2016YFC0501802)
文摘Fencing is the most common land-management practice to protect grassland degradation from livestock overgrazing on the Tibetan Plateau. However, it is unclear whether fencing reduces CO_2, CH_4, and N_2O emission. Here, we selected four vegetation types of alpine meadow(graminoid, shrub, forb, and sparse vegetation) to determine fencing effects on ecosystem respiration(Re), CH_4, and N_2O fluxes during the growing season. Despite increased average monthly ecosystem respiration(Re) for fenced graminoid vegetation at the end of the growing season, there was no significant difference between grazing and fencing across all vegetation types. Fencing significantly reduced average CH_4 uptake by about 50% in 2008 only for forb vegetation and increased average N_2O release for graminoid vegetation by 38% and 48% in 2008 and 2009,respectively. Temperature, moisture, total organic carbon, C/N, nitrate, ammonia, and/or bulk density of soil, as well as above-and belowground biomass, explained 19%~71% and 6%~33% of variation in daily and average Re and CH_4 fluxes across all vegetation types, while soil-bulk density explained 27% of variation in average N_2O fluxes. Stepwise regression showed that soil temperature and soil moisture controlled average Re, while soil moisture and bulk density controlled average CH_4 fluxes. These results indicate that abiotic factors control Re, CH_4, and N_2O fluxes; and grazing exclusion has little effect on reducing their emission—implying that climatic change rather than grazing may have a more important influence on the budgets of Re and CH_4 for the Tibetan alpine meadow during the growing season.
文摘Aim: To explore an accurate method to calculate acetabular cup anteversion after total hip arthroplasty. Method: 1) A 3D coordinate system was established with the center of the hip joint rotation center base as coordinate center. The acetabular exit plane and Pettersson formula acetabular anteversion and Riten Pradhan formula acetabular anteversion and acetabular true anteversion were drawn;2) Determine the mathematical expression of Pettersson formula acetabular anteversion α and Riten Pradhan formula acetabular anteversion β in the coordinate system. The true acetabular anteversion is projection angle of Pettersson formula acetabular anteversion α on cross-section in the presence of acetabular abduction δ, determining mathematical expression of the acetabular anteversion θ by trigonometric functions. Results: Real acetabular cup anteversion θ = arctg (tgβ/cosδ). Conclusion: The true acetabular cup anteversion and Pettersson formula anteversion and Riten Pradhan for mula anteversion were quite different. The difference was increased with the acetabular cup abduction angle increased. The formula was simple and accurate and worthy of clinical reference.
基金Major Science and Technology Special Program of Yunnan Provincial Department of Science and Technology(202102AE090018)Key Research and Development Program of Hainan Province(ZDYF2021XDNY291).
文摘[Objectives]To find a sustainable production model for potato at low latitude plateau in winter in Yunnan Province.[Methods]Xuanshu 2 potato variety was tested in prefectures of Yunnan Province.Soil covering experiment was conducted in two trials(open field experiment and green house potted experiment).Impacts of three cultivation factors were analyzed:(i)three cultivation models(T1,T2 and T3),(ii)planting density(T1,T2 and T3),(iii)soil covering(T1,T2,T3,T4)on plant growth,and yield production.[Results]The soil moisture content,temperature,roots growth,stems development,leaf area index,and number-weight of tubers per plant and per plot(g)have significantly increased with commercial yield average of 45 t/ha.[Conclusions]The combination of this method with modern agriculture mechanization should be further popularized and applied in large scale planting in regions with climatic conditions similar winter season in Yunnan Province,so as to make contribution to the satisfaction of the world population potato consumption.
基金Major Science and Technology Special Plan of Yunnan Department of Science and Technology(202102AE090018)Key Research and Development Program of Hainan Province(ZDYF2021XDNY291).
文摘[Objectives]The paper was to understand the species and pathogenicity of the pathogen causing potato early blight in winter.[Methods]The occurrence of potato early blight was investigated in 5 winter potato growing areas in Yunnan Province.The disease samples were collected from two locations(Zhutang Village and Zhanai Village,Pu'er City)where the occurrence of early blight was severe.The pathogen was isolated and purified in laboratory and identified by morphological characteristics and phylogenetic analysis of ITS gene sequence.And it was further verified via re-inoculation by Koch's rules.The growth characteristics and pathogenicity of isolates in different seasons were analyzed with 4 strains of Alternaria isolated in spring(EYZ,EYAX,TA1 and TAC)as controls.[Results]Early blight occurred in varying degrees in the 5 winter potato growing areas,and the incidence of early blight was up to 100%in some plots in Lancang County,Pu'er City.A total of 35 strains of Alternaria were isolated from plots with high incidence,which were divided into two types according to colony morphology.The first type was round colonies with smooth edges and gray white fronts,and the second type was round colonies with rough edges and gray black fronts.Three strains LC1,LC2,LC3 of the first type and two strains ZT3 and ZT8 of the second type were selected and identified as Alternaria alternata through morphological and molecular identification.Re-inoculation test further confirmed that the pathogen was A.alternata.Meantime,it was found that the growth rate of colonies isolated in winter was relatively slow,and there was no significant difference between the pathogenicity of LC1 and TA1,but the pathogenicity of strains isolated in winter was generally higher than that isolated in spring.[Conclusions]It is confirmed that the pathogen causing potato early blight in winter is A.alternata in Yunnan Province.The results will lay a foundation for the research of pathogenesis,occurrence regularity and disease control of A.alternata in winter potato.
文摘Combining with the third plenary session of the 17th "the central committee of the communist party of China on promoting rural reform and development of certain major issue decision" and the eighteenth big clear adherence to and improve the basic rural operation system and to protect farmer' s right to the contracted management of land, the land and collective income distribution, the resolution of collective economic power, this paper discusses the main content of deepening reform of China' s basic rural operation system. It elaborates we must adhere to stabilize and improve the rural basic management systems, give farmers more fully right to protect the land, develop rural land contract management rights transfer, and promote agricultural innovation and industrial organization.
文摘With the rapid development of China' s tourism industry, the country in various regional economy hotels has sprung up everywhere. Economical hotels affected due to low prices of factors, more and more pro-consumer gaze. Customers source a large part of budget hotels are from users, how to promote their hotel through the Internet is a problem that must be considered by the economy hotel, the paper through the study of economy hotel email marketing strategy wants to Economical hotels certain significance.
基金supported by the National Key Research and Development Program of China(Grant Nos.2023YFA1607100,and 2022YFA1605000)the National Natural Science Foundation of China(Grant Nos.12322511,12175112,12005111,and 11725522)。
文摘Dark matter(DM)is a major constituent of the Universe.However,no definite evidence of DM particles(denoted as“χ”)has been found in DM direct detection(DD)experiments to date.There is a novel concept of detectingχfrom evaporating primordial black holes(PBHs).We search forχemitted from PBHs by investigating their interaction with target electrons.The examined PBH masses range from 1×10^(15)to 7×10^(16)g under the current limits of PBH abundance fPBH.Using 205.4 kg·day data obtained from the CDEX-10 experiment conducted in the China Jinping Underground Laboratory,we exclude theχ-electron(χ-e)elastic-scattering cross sectionσ_(χe)~5×10^(-29)cm^(2)forχwith a mass■keV from our results.With the higher radiation background but lower energy threshold(160 eV),CDEX-10 fills a part of the gap in the previous work.If(m_(χ),σ_(χe))can be determined in the future,DD experiments are expected to impose strong constraints on fPBHfor large MPBHs.
基金funded by the National Key R&D Program of China(No.2021YFB4000604)the National Natural Science Foundations of China(No.52261041)+3 种基金Key R&D projects of Jilin Provincial Science and Technology Development Plan(No.20230201125GX)Youth Growth Science and Technology Program of Jilin Province(No.20220508001RC)Youth Innovation Promotion Association CAS(No.2022225)Independent Research Project of the State Key Laboratory of Rare Earth Resources Utilization,and Changchun Institute of Applied Chemistry,Chinese Academy of Sciences(No.110000RL86).
文摘Mg-based alloys are regarded as highly promising materials for hydrogen storage.Despite significant improvements of the properties for Mg-based alloys,challenges such as slow hydrogen absorption/desorption kinetics and high thermodynamic stability continue to limit their practical application.In this study,to assess hydrogen storage alloys with enhanced properties,incorporating both internal microstructure modulation through the preparation of amorphous/nanocrystalline structures and surface property enhancement with the addition of Cu and carbon nanotubes(CNTs),the kinetic properties of activation and hydrogenation,thermodynamic properties,and dehydrogenation kinetics are tested.The results reveal a complementary interaction between the added Cu and CNTs,contributing to the superior hydrogen storage performance observed in sample 7A-2Cu-1CNTs with an amorphous/nanocrystalline structure compared to the other experimental samples.Additionally,the samples are fully activated after the initial hydrogen absorption and desorption cycle,demonstrating outstanding hydrogenation kinetics under both high and low temperature experimental conditions.Particularly noteworthy is that the hydrogen absorption exceeds 1.8 wt.% within one hour at 333 K.Furthermore,the activation energy for dehydrogenation is decreased to 64.71 kJ·mol^(–1).This research may offer novel insights for the design of new-type Mg-based hydrogen storage alloys,which possess milder conditions for hydrogen absorption and desorption.