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Overexpression of OsCAX2 in indica rice reduces cadmium accumulation in grains without yield loss
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作者 Zhi Hu Wenli Zou +4 位作者 Huijing Ye Jie Ma Lijun Meng Jingguang Chen Guoyou Ye 《Journal of Integrative Agriculture》 2026年第1期390-393,共4页
Highlights OsCAX2 is localized to tonoplast,and cadmium induces its expression.OsCAX2 overexpression reduces cadmium concentration in indica rice grains by 49.1%.Cadmium(Cd)exposure poses significant health risks to h... Highlights OsCAX2 is localized to tonoplast,and cadmium induces its expression.OsCAX2 overexpression reduces cadmium concentration in indica rice grains by 49.1%.Cadmium(Cd)exposure poses significant health risks to humans,and the International Agency for Research on Cancer has classified it as a Group I carcinogen.Cadmium undergoes minimal metabolism in the human body;consequently,prolonged Cd^(2+)exposure can cause severe damage to multiple organs including the liver,kidneys,lungs,bones,and immune system(Shao et al.2024).Rice,one of the three global staple crops,and Cd exposure in humans primarily occurs the consumption of contaminated rice grains.The contribution of rice to the total dietary Cd intake is over 50% for non-smoking Asian populations(Chen et al.2018;Shi et al.2020). 展开更多
关键词 grain cadmium accumulation yield loss cadmium concentration indica rice grains OscAX TONOPLAST cadmium induction
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Proteomic Analysis Revealing Protein Expression in Rice Grain Containing Differential Protein and Amino Acid Contents
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作者 Krishnendu CHATTOPADHYAY Arabinda MAHANTY +6 位作者 Nutan MOHARANA Shuvendu Shekhar MOHAPATRA Torit Baran BAGCHI Koushik CHAKRABORTY Joydeep BANERJEE Bimal Prasanna MOHANTY Trilochan MOHAPATRA 《Rice science》 2026年第1期9-14,I0012-I0027,共22页
CR Dhan 310(CRD310),a biofortified rice variety,contains a significantly higher level of grain protein compared with its recurrent parent Naveen(NV),as well as most adapted high-yielding rice varieties in India.Althou... CR Dhan 310(CRD310),a biofortified rice variety,contains a significantly higher level of grain protein compared with its recurrent parent Naveen(NV),as well as most adapted high-yielding rice varieties in India.Although a limited investigation depicted that CRD310 contained higher levels of glutelin and some essential amino acids,detailed biochemical,molecular,and cellular mechanisms remain to be studied.As one of the means to identify the proteins and understand the underlying mechanism of higher proteins accumulation in grains of CRD310,the comparative proteomics was undertaken on grains of CRD310 and NV at the yellow ripening stage. 展开更多
关键词 grain protein rice grain comparative proteomics essential amino acids identify proteins protein accumulation biochemical mechanisms amino acidsdetailed
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Research on grain supply and demand matching in the Beijing-Tianjin-Hebei region based on ecosystem service flows
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作者 Jiaxin Miao Peipei Pan +7 位作者 Bingyu Liu XiaowenYuan Zijun Pan Linsi Li Xinyun Wang Yuan Wang Yongqiang Cao Tianyuan Zhang 《Journal of Integrative Agriculture》 2026年第2期460-480,共21页
A comprehensive assessment of grain supply,demand,and ecosystem service flows is essential for identifying grain movement pathways,ensuring regional grain security,and guiding sustainable management strategies.However... A comprehensive assessment of grain supply,demand,and ecosystem service flows is essential for identifying grain movement pathways,ensuring regional grain security,and guiding sustainable management strategies.However,current studies primarily focus on short-term grain provision services while neglecting the spatiotemporal variations in grain flows across different scales.This gap limits the identification of dynamic matching relationships and the formulation of optimization strategies for balancing grain flows.This study examined the spatiotemporal evolution of grain supply and demand in the Beijing-Tianjin-Hebei(BTH)region from 1980 to 2020.Using the Enhanced TwoStep Floating Catchment Area method,the grain provision ecosystem service flows were quantified,the changes in supply–demand matching under different grain flow scenarios were analyzed and the optimal distance threshold for grain flows was investigated.The results revealed that grain production follows a spatial distribution pattern characterized by high levels in the southeast and low levels in the northwest.A significant mismatch exists between supply and demand,and it shows a scale effect.Deficit areas are mainly concentrated in the northwest,while surplus areas are mainly located in the central and southern regions.As the spatial scale increases,the ecosystem service supply–demand ratio(SDR)classification becomes more clustered,while it exhibits greater spatial SDR heterogeneity at smaller scales.This study examined two distinct scenarios of grain provision ecosystem service flow dynamics based on 100 and 200 km distance thresholds.The flow increased significantly,from 2.17 to 11.81million tons in the first scenario and from 2.41 to 12.37 million tons in the second scenario over nearly 40 years,forming a spatial movement pattern from the central and southern regions to the surrounding areas.Large flows were mainly concentrated in the interior of urban centers,with significant outflows between cities such as Baoding,Shijiazhuang,Xingtai,and Hengshui.At the county scale,supply–demand matching patterns remained consistent between the grain flows in the two scenarios.Notably,incorporating grain flow dynamics significantly reduced the number of grain-deficit areas compared to scenarios without grain flow.In 2020,grain-deficit counties decreased by28.79 and 37.88%,and cities by 12.50 and 25.0%under the two scenarios,respectively.Furthermore,the distance threshold for achieving optimal supply and demand matching at the county scale was longer than at the city scale in both grain flow scenarios.This study provides valuable insights into the dynamic relationships and heterogeneous patterns of grain matching,and expands the research perspective on grain and ecosystem service flows across various spatiotemporal scales. 展开更多
关键词 Beijing-Tianjin-Hebei region grain provision ecosystem service grain flow supply and demand match distance threshold
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Effects of Element Y on Grain Refinement and Mechanical Properties of Cast Al-2.2Li-1.5Cu-Based Alloy
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作者 Wang Xu Dang Qian +3 位作者 Ma Hongyao Liu Guohuai Zhang Chi Wang Zhaodong 《稀有金属材料与工程》 北大核心 2026年第3期602-614,共13页
The effect of trace addition of 0.1wt%Y on the grain refinement and mechanical properties of Al-2.2Li-1.5Cu-0.5Mg-1Zn-0.2Zr-0.2Sc alloys at as-cast and heat-treated states was investigated.Results show that the additi... The effect of trace addition of 0.1wt%Y on the grain refinement and mechanical properties of Al-2.2Li-1.5Cu-0.5Mg-1Zn-0.2Zr-0.2Sc alloys at as-cast and heat-treated states was investigated.Results show that the addition of 0.1wt%Y into the Al-2.2Li-1.5Cu-0.5Mg-1Zn-0.2Zr-0.2Sc alloys can elevate the nucleation temperature of the Al_(3)(Sc,Zr)phase,leading to the preferential precipitation of the Al_(3)(Sc,Zr)phase and increasing the amount of Al_(3)(Sc,Zr)phase in the matrix.Al_(3)(Sc,Zr)phase can also act as a heterogeneous nucleation site in theα-Al matrix to promote nucleation and refine grains.The addition of element Y changes the precipitation phase characteristics at the grain boundaries in the as-cast alloy,which changes the distribution characteristics of secondary phases from initially continuous and coarse strip-like distribution at grain boundaries into the discontinuous dot-like and rod-like distribution.Besides,the size of secondary phases becomes smaller and their amount increases.Under the combined effects of grain refinement strengthening and precipitation strengthening,the Al-2.2Li-1.5Cu-0.5Mg-1Zn-0.2Zr-0.2Sc-0.1Y alloy after 175℃/10 h aging treatment achieves an ultimate tensile strength of 412 MPa and an elongation of 6.3%.Compared with those of the alloy without Y addition,the ultimate tensile strength and elongation of the added alloy increase by 16.1%and 53.7%,respectively. 展开更多
关键词 Al-Li alloy element Y heat treatment grain refinement
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Mechanisms of Pore-Grain Boundary Interactions Influencing Nanoindentation Behavior in Pure Nickel: A Molecular Dynamics Study
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作者 Chen-Xi Hu Wu-Gui Jiang +1 位作者 Jin Wang Tian-Yu He 《Computers, Materials & Continua》 2026年第1期368-388,共21页
THE mechanical response and deformation mechanisms of pure nickel under nanoindentation were systematically investigated using molecular dynamics(MD)simulations,with a particular focus on the novel interplay between c... THE mechanical response and deformation mechanisms of pure nickel under nanoindentation were systematically investigated using molecular dynamics(MD)simulations,with a particular focus on the novel interplay between crystallographic orientation,grain boundary(GB)proximity,and pore characteristics(size/location).This study compares single-crystal nickel models along[100],[110],and[111]orientations with equiaxed polycrystalline models containing 0,1,and 2.5 nm pores in surface and subsurface configurations.Our results reveal that crystallographic anisotropy manifests as a 24.4%higher elastic modulus and 22.2%greater hardness in[111]-oriented single crystals compared to[100].Pore-GB synergistic effects are found to dominate the deformation behavior:2.5 nm subsurface pores reduce hardness by 25.2%through stress concentration and dislocation annihilation at GBs,whereas surface pores enable mechanical recovery via accelerated dislocation generation post-collapse.Additionally,size-dependent deformation regimes were identified,with 1 nm pores inducing negligible perturbation due to rapid atomic rearrangement,in contrast with persistent softening in 2.5 nm pores.These findings establish atomic-scale design principles for defect engineering in nickel-based aerospace components,demonstrating how crystallographic orientation,pore configuration,and GB interactions collectively govern nanoindentation behavior. 展开更多
关键词 Pure nickel NANOINDENTATION molecular dynamics PORE grain boundary
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Mapping the strain-localization evolution of grain boundary and its interactions with slip/twin at the microscale
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作者 Ran Ni Saijun Huang +6 位作者 Lingling Fan Kang Wei Ying Zeng Jiang Zheng Qudong Wang Hao Zhou Dongdi Yin 《Journal of Magnesium and Alloys》 2026年第1期251-267,共17页
Plastic strain in polycrystalline metals is highly localized in grain boundaries(GBs),slip bands(SBs)and twins.While extensive research has focused on intra-granular deformation mechanisms such as slip and twinning,st... Plastic strain in polycrystalline metals is highly localized in grain boundaries(GBs),slip bands(SBs)and twins.While extensive research has focused on intra-granular deformation mechanisms such as slip and twinning,strain localization at GBs has been largely overlooked.In this study,high-resolution digital image correlation(HRDIC)was employed to capture the strain distribution and its evolution during tension in an extruded pure Mg sheet.Particular attention was paid to strain localization at GBs and its governing factors.Results reveal that,at 3%applied strain,approximately 10%of GBs were categorized as extremely-high-strain GBs(defined as the GB where at least 20 data points have an effective shear strain(ε_(eff))value exceeding the 99th percentile of the overallεeff distribution),and the majority(84%)of them were observed to deform at even 0.5%applied strain.This suggests that early-stage deformation plays a critical role in subsequent GB strain localization.The mean strain value and grain boundary sliding(GBS)displacement of GBs increased significantly with applied strain,with progressively accelerating increasing rates observed in most instances.Most(~62%)GBs exhibiting slip transfer showed low strain,while a small fraction(~8%)of them exhibited extremely high strain.This indicates that slip transfer can mitigate GB strain localization in most cases.However,complex local conditions are also critical,and case-by-case analysis is essential.Moreover,GBs with misorientation angles ranging from 50°to 80°were found to be more likely to exhibit extremely high strain.This work provides valuable insights into GB strain localization,which is critical for further understanding the plastic deformation of polycrystalline Mg. 展开更多
关键词 Polycrystalline Mg grain boundary Strain-localization evolution Slip transfer HRDIC
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Effect of grain size on fatigue behaviors of Mg-2.6Nd-0.35Zn-xZr alloys
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作者 Lun-yong Zhang Yan-ping Chen +5 位作者 Xian-xing Wang Hong-xian Shen Hong-hui Liu Fu-yang Cao Zhi-liang Ning Jian-fei Sun 《China Foundry》 2026年第2期186-196,共11页
High-performance magnesium alloys are in great demand to meet the lightweight design requirements of aircraft.Grain size has long been recognized as a key factor influencing the mechanical properties of alloys.This st... High-performance magnesium alloys are in great demand to meet the lightweight design requirements of aircraft.Grain size has long been recognized as a key factor influencing the mechanical properties of alloys.This study investigates the effect of grain size,controlled by Zr addition,on the fatigue behavior of a recently developed low-cost Mg-2.6Nd-0.35Zn alloy,through systematic characterization and analysis of stress-life(S-N)curves,fatigue crack propagation,fracture surface morphology,stress intensity factor,and crack propagation threshold.The results show that after heat treatment(solution at 525±5℃ for 8 h and water quenching at 60-80℃,followed by aging at 250±5℃for 14 h and then air cooling),coarse-grained specimens(average grain size approximately 596μm)containing 0.12wt.%Zr exhibit greater resistance to fatigue crack propagation than fine-grained specimens(average grain size approximately 94μm)containing 0.46wt.%Zr.Coarse grains promote intergranular fracture,while fine grains favor transgranular fracture.In addition,coarse grains reduce the sensitivity of the crack tip to stress concentration.Furthermore,fine-grained samples demonstrate a longer total fatigue life,owing to their superior resistance to crack initiation,which significantly prolongs the crack initiation stage.These findings highlight the importance of optimizing grain size to achieve the best possible fatigue resistance in Mg-Nd-Zn-Zr alloys for practical engineering applications. 展开更多
关键词 Mg-Nd-Zn-Zr alloys grain size fatigue behaviors crack propagation crack initiation
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Grain & Oil Science and Technology
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《Grain & Oil Science and Technology》 2026年第1期F0003-F0003,共1页
Aims&Scope Grain&Oil Science and Technology(GOST),quarterly,is a peer-reviewed Open Access(OA)journal with distinctive features in the field of grain and oil food research.Upon acceptance all articles are perm... Aims&Scope Grain&Oil Science and Technology(GOST),quarterly,is a peer-reviewed Open Access(OA)journal with distinctive features in the field of grain and oil food research.Upon acceptance all articles are permanently and freely available on ScienceDirect.GOST publishes original research papers and relevant review articles focusing on grain and oil food science and technology.The journal primarily covers new achievements,advanced technologies,and research progress in key areas such as grain and oil food engineering,food science,and food safety.It is dedicated to building an international academic exchange platform for grain and oil food science and technology that spans the entire chain from post-harvest grain handling to food consumption. 展开更多
关键词 oil food technology peer reviewed open access review articles original research papers research grain
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Spatial Variation in Grain Size of Riparian Dunes in Typical Cold and Arid Deserts of China and Its Implications for Identifying Sediment Sources
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作者 LI Xiaomei YAN Ping +3 位作者 CAO Liguo WANG Xiaoxu LIU Xiaokang CHEN Hao 《Chinese Geographical Science》 2026年第2期291-305,共15页
Riparian dunes in deserts exhibit unique geographic features due to aeolian-fluvial interactions.In this study,we collected 510 surface sediment samples from eight drainage basins and conducted a systematic analysis t... Riparian dunes in deserts exhibit unique geographic features due to aeolian-fluvial interactions.In this study,we collected 510 surface sediment samples from eight drainage basins and conducted a systematic analysis to examine the grain size characteristics of major riparian dunes in the typical cold and arid deserts of China.The results indicate that major riparian dunes of deserts in study area can be classified into three types based on their grain size characteristics.The Bartlett test of sphericity and the Kaiser-Meyer-Olkin(KMO)test were also performed,and their significance values were found to be 0.000 and 0.584,respectively.The results of the principal component analysis revealed that the cumulative contribution rate of the total variance reached 85.9%for the two principal components with characteristic roots greater than 1.0.The primary principal component included medium sand,whereas the secondary principal component included fine sand.We conducted a cluster analysis and classified the samples into three major types.Type I rivers include the Keriya River,Langqu River,Tora River and Heihe River,which are characterized by by fine particle size,and well-sorted.Type II includes Mu Bulag River,Kuye River,and the Xar Moron River,Compared with type I,it has a relatively coarser mean grain size and relatively poor sorting for this type.Type III includes the Maquan River,which is characterized mainly by fine sand and medium sand,accounting for more than 90%,and the sorting coefficient(0.52)suggests relatively well sorting in this pattern.Moreover,principal component analysis was applied to determine the particle sizes of samples from different watersheds.Moreover,these sediments exhibit both hydromorphic and aeolian features.At the drainage basin scale,the mode and intensity of aeolian-fluvial interactions depend on climatic conditions.In arid and semi-arid climate regions,wind is the dominant force,and the grain size exhibits significant aeolian features.Conversely,in the semi-humid region,flowing water is the dominant force,and riparian dunes in this region are formed by aeolian-fluvial interaction.The angle between the wind direction and flow direction in different reaches influences both the supply of sediment sources and the development of riparian dunes.This study will provide a new perspective for evaluating aeolian-fluvial interactions on riparian dunes in the deserts of China’s cold and arid regions. 展开更多
关键词 riparian dune grain size aeolian-fluvial interaction cold and arid deserts China
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Investigation of the impact of grain boundary hydrogen concentration on hydrogen embrittlement sensitivity of polycrystalline Fe:Molecular dynamics insights
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作者 Qiaoyun Tang Wei Gao 《Smart Molecules》 2026年第1期134-144,共11页
This study investigates the influence of hydrogen concentration at grain boundaries on the sensitivity of polycrystalline iron to hydrogen embrittlement using molecular dynamics simulations.These simulations reveal th... This study investigates the influence of hydrogen concentration at grain boundaries on the sensitivity of polycrystalline iron to hydrogen embrittlement using molecular dynamics simulations.These simulations reveal the diffusion behavior of hydrogen atoms at grain boundaries and their consequential impact on the hydrogen embrittlement sensitivity of iron alloys.The findings indicate that as the hydrogen concentration increases,both the yield strength and ultimate tensile strength of Fe-H alloys exhibit a declining trend.Moreover,the capture of hydrogen atoms at the grain boundaries significantly influences the fracture toughness of the material and promotes the formation and propagation of cracks.This study provides a novel theoretical basis for understanding and predicting the hydrogen embrittlement behavior of iron-based materials in hydrogen-rich environments,offering valuable insights for the design and development of Fe alloys with enhanced resistance to hydrogen embrittlement. 展开更多
关键词 grain boundary hydrogen atom concentration hydrogen embrittlement sensitivity molecular dynamics simulation
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Suppressors of Cytokinin Receptor Mutant pal1/ohk4 Confer Favorable Alleles of Grain Number 1a(Gn1a)for Improving Grain Yield in japonica Rice
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作者 JIA Huichao CHUN Yan +9 位作者 Ashmit KUMAR MO Tianyu WANG Haifeng GUO Shengyuan FANG Jingjing ZHAO Jinfeng SUN Wei ZHANG Shiyong YUAN Shoujiang LI Xueyong 《Rice science》 2026年第1期81-98,I0068-I0073,共24页
Panicle number per plant,grain number per panicle,and grain weight are three key factors influencing rice grain yield.Gn1a,a major QTL for grain number per panicle,encodes the cytokinin oxidase/dehydrogenase(CKX)OsCKX... Panicle number per plant,grain number per panicle,and grain weight are three key factors influencing rice grain yield.Gn1a,a major QTL for grain number per panicle,encodes the cytokinin oxidase/dehydrogenase(CKX)OsCKX2.While the use of elite Gn1a alleles has been well documented in indica rice cultivars,their potential in japonica rice remains largely unexplored.In this study,we characterized three suppressor mutants of the rice cytokinin receptor mutant pal1/ohk4 and found that all causal genes were novel alleles of Gn1a identified through the MutMap approach.These three suppressor mutants caused single amino acid substitutions in the FAD-binding domain(G556D and G156D)and the cytokinin-binding domain(Y357C),resulting in significantly reduced enzymatic activity of OsCKX2 and elevated cytokinin levels in the panicle.Haplotype analysis of Gn1a using a natural population from the 3K Rice Genomes Project showed that G556D,G156D,and Y357C were novel alleles of Gn1a.G556,G156,and Y357 were highly conserved,whereas four natural variants G54A,A105V,H116R,and N535K identified in different haplotypes of Gn1a showed extremely low conservation.By backcrossing the suppressor mutants with their original wild-type Huaidao 5,an elite japonica rice variety,we developed improved lines carrying only the gn1a mutation.The improved lines showed a significant increase in grain number per panicle,grain weight,panicle number per plant,plant height,and stem thickness,leading to a 25.7%-28.7%increase in grain yield per plot compared with Huaidao 5.This study provides valuable Gn1a alleles for synergistic improvement of the three key yield factors and offers germplasm resources for high-yielding breeding in japonica rice. 展开更多
关键词 grain number panicle size CYTOKININ Gn1a OsCKX2 OHK4/OsHK4 SUPPRESSOR Oryza sativa
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Influences of Milling Degree on Zinc Bioavailability in Rice Grains Varied in Zinc and Phytic Acid Levels
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作者 HUO Shaojie LIN Jiaqi +3 位作者 SUN Yuxuan WU Dianxing SHU Xiaoli WANG Yin 《Rice science》 2026年第1期25-29,I0041-I0045,共10页
Zinc(Zn)deficiency is a global health issue,exacerbated by low Zn concentration and poor bioavailability in rice,primarily due to phytic acid(PA)interference.In this study,four doubled haploid(DH)progenies(DH1,DH11,DH... Zinc(Zn)deficiency is a global health issue,exacerbated by low Zn concentration and poor bioavailability in rice,primarily due to phytic acid(PA)interference.In this study,four doubled haploid(DH)progenies(DH1,DH11,DH18,and DH29)with distinct Zn and PA profiles were used to evaluate the effects of varying degrees of milling(DOM)on Zn bioavailability.Results showed DOM followed a double-exponential decay pattern(R^(2)>0.99)with milling time,varying among the four DH lines under identical milling conditions.As DOM increased,Zn,PA,and phosphorus(P)concentrations decreased progressively. 展开更多
关键词 zinc deficiency milling degree zinc bioavailability degrees milling dom double exponential decay pattern rice grains phytic acid
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Grain Photosynthesis and Filling Characteristics of Rice Varieties with Different Grain Weights
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作者 Jinge Li Chuyao Wang +2 位作者 Fangbo Cao Min Huang Jiana Chen 《Phyton-International Journal of Experimental Botany》 2025年第7期2155-2165,共11页
Grain filling is a critical determinant of yield and quality in rice.This study aims to clarify the association between grain photosynthesis and the filling rate of rice varieties with different grain weights,providin... Grain filling is a critical determinant of yield and quality in rice.This study aims to clarify the association between grain photosynthesis and the filling rate of rice varieties with different grain weights,providing a theoretical foundation for optimizing grain-filling processes.Two rice varieties with similar growth duration but different grain weights were selected:a large-grain variety,Lingliangyou 268(L268),and a small-grain variety,Ruiliangyou 1053(R1053).Differences in grain filling,grain photosynthetic rate,and grain chlorophyll content were systematically examined during the filling stage.Results showed significant differences in grain-filling,grain photosynthetic rate,and grain chlorophyll content between large-grain and small-grain rice varieties.The grain photosynthetic rate of L268 was a significantly higher than R1053.L268 also exhibited significantly higher initial grain filling rate,maximum grainfilling rate,and mean grain filling rate compared to R1053.Throughout the grain filling period,L268 showed higher grain chlorophyll content(including chlorophyll a,chlorophyll b,and total chlorophyll)than R1053.The increase in chlorophyll content,particularly total chlorophyll,enhanced the grain photosynthetic rate during the early and middle stages of grain filling significantly.These findings suggested that rice varieties with higher grain weights exhibited stronger panicle photosynthetic capacity due to their higher chlorophyll content.The enhanced grain photosynthetic rate contributed to improved grain filling and increased grain weight. 展开更多
关键词 grain chlorophyll content grain filling grain weight photosynthetic capacity panicle photosynthesis rice panicle
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Zn segregation in BCC Fe grain boundaries and its role in liquid metal embrittlement revealed by atomistic simulations
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作者 Haojie Mei Luyao Cheng +4 位作者 Liang Chen Feifei Wang Guiqin Yang Jinfu Li Lingti Kong 《Journal of Materials Science & Technology》 2025年第22期21-30,共10页
The liquid metal embrittlement(LME)of advanced high-strength steels caused by zinc(Zn)has become a critical issue hindering their widespread application in the automotive industry.In this study,atomic-scale simulation... The liquid metal embrittlement(LME)of advanced high-strength steels caused by zinc(Zn)has become a critical issue hindering their widespread application in the automotive industry.In this study,atomic-scale simulations are carried out to elucidate the underlying cause of this phenomenon,namely grain boundary embrittlement due to Zn segregation at iron(Fe)grain boundaries.A machine learning moment tensor interatomic potential for the Fe-Zn binary system is developed,based on which the thermodynamics of grain boundary segregation is evaluated.The yielded segregation energy spectrum of Zn in BCC Fe reveals the quantitative relationship between the average segregation concentration of Zn at Fe grain boundaries and the macroscopic Zn content,temperature,and fraction of grain boundary atoms.It suggests a strong thermodynamic driving force for Zn segregation at the Fe grain boundaries,which correlates directly with the grain boundary energy:high-energy grain boundaries can accommodate a large amount of Zn atoms,while low-energy grain boundaries exhibit a certain degree of repulsion to Zn.Kinetically,Zn enters the grain boundaries more easily through diffusion than by penetration.Nonetheless,the grain boundary embrittlement caused by Zn penetration is more severe than that by Zn diffusion.The embrittlement effect generally increases linearly with the increase in Zn concentration at the grain boundary.Altogether,it suggests that the LME in steels induced by grain boundary segregation of Zn emerges as a combined consequence of Zn melt penetration and solid-state diffusion of Zn atoms. 展开更多
关键词 Liquid metal embrittlement Machine learning interatomic potential grain boundary segregation grain boundary penetration grain boundary diffusion
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Reasonable dry cultivation methods can balance the yield and grain quality of rice 被引量:1
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作者 Jia Wu Luqi Zhang +4 位作者 Ziyi Wang Fan Ge Hao Zhang Jianchang Yang Yajie Zhang 《Journal of Integrative Agriculture》 2025年第3期1030-1043,共14页
Reducing water consumption in rice production in China without affecting grain yield and quality is a significant challenge.This study explored how various dry cultivation methods could improve rice quality while bala... Reducing water consumption in rice production in China without affecting grain yield and quality is a significant challenge.This study explored how various dry cultivation methods could improve rice quality while balancing yield to maintain sustainable rice production.A japonica upland rice cultivar and a japonica paddy rice cultivar were cultivated in the field with three cultivation methods:plastic film mulching dry cultivation(PFMC),bare dry cultivation(BC),and continuous flooding cultivation(CF)as control.There was no significant difference in upland rice yield between PFMC and BC,nor in paddy rice yield between PFMC and CF.Compared with CF,the two varieties'yields decreased significantly with BC.Dry cultivation,especially PFMC,could decrease the active filling period,chalky rice rate,chalkiness,amylose content,gel consistency,breakdown viscosity,the ratio of glutelin to prolamin,and leaf senescence while increasing water use efficiency,protein components content,setback viscosity,grain starch branching enzyme(Q-enzyme)activity,and average filling rate.Compared with paddy rice,upland rice had a lower yield,shorter active filling period,lower chalkiness grain rate and gel consistency,higher amylose content,breakdown viscosity,protein components content,and average filling rate.Grain Q-enzyme activity and grain-filling parameters were closely related to rice quality.Reasonable dry cultivation methods could balance yield and quality,especially by improving rice's nutritional and appearance quality. 展开更多
关键词 RICE dry cultivation grain quality YIELD protein components grain filling
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Modulation of rice grain shape and appearance by the GS10-encoded long coiled-coil protein 被引量:1
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作者 Yanmin Luo Yuyu Chen +12 位作者 Pao Xue Beifang Wang Yiwei Kang Yue Zhang Daibo Chen Yongbo Hong Weixun Wu Qunen Liu Xiaodeng Zhan Yongjun Lin Shihua Cheng Yingxin Zhang Liyong Cao 《The Crop Journal》 2025年第1期158-169,共12页
Rice grain size is a primary characteristic essential for artificial domestication and breeding,governed by grain length,width,and thickness.In this study,we cloned Grain Size 10(GS10),a novel gene via mapbased clonin... Rice grain size is a primary characteristic essential for artificial domestication and breeding,governed by grain length,width,and thickness.In this study,we cloned Grain Size 10(GS10),a novel gene via mapbased cloning.Biochemical,molecular,and genetic studies were performed to elucidate the GS10 involved grain size mechanism in rice.Mutant of GS10 lead to reduced grain size due to alterations in cell expansion.Additionally,GS10 is responsible for the formation of notched-belly grains,especially in smaller grain varieties possessing loss-function mutations.Overexpression of GS10 in Nipponbare results in increasing grain length,grain weight and improve the appearance quality of rice.GS10 encodes conserved protein with uncharacterized function.Furthermore,GS10 regulates the grain size by interacting OsBRICK1,a subunit of the WAVE complex that governs actin nucleation and affects the assembly of microfilaments in rice.Together,our study demonstrates that,GS10 positively regulates the grain length and grain weight,which is beneficial for further improvements in yield characteristics. 展开更多
关键词 GS10 grain size grain weight Appearance quality MICROFILAMENTS
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Numerical and experimental investigation of the influence of temperature and grain size on the fracture behavior of rock 被引量:1
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作者 Hooman Rezaee Majid Noorian-Bidgoli 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第2期1102-1119,共18页
Understanding the fracture behavior of rocks subjected to temperature and accounting for the rock's texture is vital for safe and efficient design.Prior studies have often focused on isolated aspects of rock fract... Understanding the fracture behavior of rocks subjected to temperature and accounting for the rock's texture is vital for safe and efficient design.Prior studies have often focused on isolated aspects of rock fracture behavior,neglecting the combined influence of grain size and temperature on fracture behavior.This study employs specimens based on the particle flow code-grain based model to scrutinize the influence of temperature and grain size discrepancies on the fracture characteristics of sandstone.In pursuit of this goal,we manufactured ninety-six semi-circular bend specimens with grain sizes spanning from 0.5 mm to 1.5 mm,predicated on the mineral composition of sandstone.Recognizing the significance of intra-granular and inter-granular fractures,the grains were considered deformable and susceptible to breakage.The numerical model was calibrated using the results of uniaxial compressive strength(UCS)and Brazilian tests.We implemented thermo-mechanical coupled analysis to simulate mode Ⅰ,mode Ⅱ,and mixed mode(Ⅰ-Ⅱ)fracture toughness tests and subsequently studied alterations in the fracture behavior of sandstone at temperatures from 25℃ to 700℃.Our findings revealed increased fracture toughness as the temperature escalated from 25℃ to 200℃.However,beyond the threshold of 200℃,we noted a decline in fracture toughness.More specifically,the drop in mode Ⅰ fracture toughness was more pronounced in specimens with finer grains than those with coarser grains.Contrarily,the trend was reversed for mode Ⅱ fracture toughness.In contrast,the reduction of mixed mode(Ⅰ-Ⅱ)fracture toughness seemed almost linear across all grain sizes.Furthermore,we identified a correlation between temperature and grain size and their collective impact on crack propagation patterns.Comparing our results with established theoretical benchmarks,we confirmed that both temperature and grain size variations influence the fracture envelopes of sandstone. 展开更多
关键词 Fracture toughness TEMPERATURE grain size Numerical analysis grain based model
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Ultrafine-grained refractory high-entropy alloy with oxygen control and high mechanical performance 被引量:1
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作者 Yaping Sun Chao Hou +3 位作者 Yurong Li Tielong Han Xuemei Liu Xiaoyan Song 《Journal of Materials Science & Technology》 2025年第12期45-57,共13页
Grain boundary engineering plays a significant role in the improvement of strength and plasticity of alloys. However, in refractory high-entropy alloys, the susceptibility of grain boundaries to oxygen presents a bott... Grain boundary engineering plays a significant role in the improvement of strength and plasticity of alloys. However, in refractory high-entropy alloys, the susceptibility of grain boundaries to oxygen presents a bottleneck in achieving high mechanical performance. Creating a large number of clean grain boundaries in refractory high-entropy alloys is a challenge. In this study, an ultrafine-grained (UFG) NbMoTaW alloy with high grain-boundary cohesion was prepared by powder metallurgy, taking advantages of rapid hot-pressing sintering and full-process inert atmosphere protection from powder synthesis to sintering. By oxygen control and an increase in the proportion of grain boundaries, the segregation of oxygen and formation of oxides at grain boundaries were strongly mitigated, thus the intrinsic high cohesion of the interfaces was preserved. Compared to the coarse-grained alloys prepared by arc-melting and those sintered by traditional powder metallurgy methods, the UFG NbMoTaW alloy demonstrated simultaneously increased strength and plasticity at ambient temperature. The highly cohesive grain boundaries not only reduce brittle fractures effectively but also promote intragranular deformation. Consequently, the UFG NbMoTaW alloy achieved a high yield strength even at elevated temperatures, with a remarkable performance of 1117 MPa at 1200 ℃. This work provides a feasible solution for producing refractory high-entropy alloys with low impurity content, refined microstructure, and excellent mechanical performance. 展开更多
关键词 Refractory high-entropy alloy Ultrafine-grained structure grain boundary cohesion Mechanical performance High-temperature strength
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Effect of Grain Refinement on Grain Boundary Diffusion Process and Magnetic Properties of Sintered NdFeB Magnets
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作者 Wang Mei Liu Weiming +8 位作者 Peng Buzhuang Wang Qian Wang Fei Zhang Yumeng Gu Xiaoqian Wang Qi Xiao Guiyong Liu Yan Zhu Xinde 《稀有金属材料与工程》 北大核心 2025年第11期2768-2776,共9页
Three types of NdFeB magnets with the same composition and different grain sizes were prepared,and then the grain boundary diffusion was conducted using metal Tb under the same technical parameters.The effect of grain... Three types of NdFeB magnets with the same composition and different grain sizes were prepared,and then the grain boundary diffusion was conducted using metal Tb under the same technical parameters.The effect of grain size on the grain boundary diffusion process and properties of sintered NdFeB magnets was investigated.The diffusion process was assessed using X-ray diffractometer,field emission scanning electron microscope,and electron probe microanalyzer.The magnetic properties of the magnet before and after diffusion were investigated.The results show that the grain refinement of the magnet leads to higher Tb utilization efficiency and results in higher coercivity at different temperatures.It can be attributed to the formation of a deeper and more complete core-shell structure,resulting in better magnetic isolation and higher anisotropy of the Nd_(2)Fe_(14)B grains.This work may shed light on developing high coercivity with low heavy rare earth elements through grain refinement. 展开更多
关键词 sintered NdFeB magnets grain refinement grain boundary diffusion COERCIVITY
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Prolonged endosperm filling and embryo enlargement phases contribute to the impaired development of inferior grains in japonica rice
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作者 Lu An Yang Tao +4 位作者 Hao Chen Ganghua Li Yanfeng Ding Matthew JPaul Zhenghui Liu 《The Crop Journal》 2025年第5期1595-1606,共12页
Inferior grains exhibit delayed developmental processes and reduced metabolic activities compared to superior grains,leading to unstable rice yield and quality.While significant advancements have been achieved in eluc... Inferior grains exhibit delayed developmental processes and reduced metabolic activities compared to superior grains,leading to unstable rice yield and quality.While significant advancements have been achieved in elucidating the physiology of endosperm filling in inferior grains,the role of the embryo remains underexplored and warrants comprehensive investigation.Two Wuyujing 3 mutants,DW024(relatively synchronous;syn-DW024)and DW179(significantly asynchronous;asyn-DW179),with different grain-filling patterns were used in this study.Samples of superior and inferior grains were collected at intervals from 5 to 60 d after fertilization and subsequently dissected into subsamples of the embryo and endosperm.Histochemical staining,biochemical analysis,and RNA sequencing(RNA-seq)were combined to systematically compare developmental and physiological traits between superior and inferior grains.Combining hierarchical clustering of mRNA datasets revealed three developmental phases of the endosperm and embryo:morphogenesis,endosperm filling/embryo enlargement,and maturation.In both syn-DW024 and asyn-DW179,the duration of the endosperm/embryo morphogenesis phase was identical in superior and inferior grains.The inferior grains of asyn-DW179 exhibited a 10-day prolongation in the endosperm filling phase and a 20-day extension in the embryo enlargement phase compared to the superior grains.The endosperm of inferior grains exhibited higher contents of sugars and free amino acids,along with slower accumulation of storage compounds,which was associated with the down-regulation of genes for starch synthesis and ABA signaling.In addition,transporters for nutrient exchanges between endosperm and embryo were down-regulated,suggesting a potential role of the embryo in adjusting the endosperm filling process.Collectively,our results reveal that the prolonged phases of endosperm filling and embryo enlargement may underlie the impaired development of inferior grains,offering a new perspective for breeding or cultivating rice with uniform grain quality. 展开更多
关键词 Rice Inferior grain ENDOSPERM EMBRYO grain development
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