Bismuth-based catalysts are highly promising for the electrochemical carbon dioxide reduction reaction(eCO_(2)RR)to formate product.However,achieving high activity and selectivity towards formate and ensuring long-ter...Bismuth-based catalysts are highly promising for the electrochemical carbon dioxide reduction reaction(eCO_(2)RR)to formate product.However,achieving high activity and selectivity towards formate and ensuring long-term stability remains challenging.This work reports the oxygen plasma inducing strategy to construct the abundant grain boundaries of Bi/BiO_x on ultrathin two-dimensional Bi nanosheets.The oxygen plasma-treated Bi nanosheet(OP-Bi)exhibits over 90%Faradaic efficiency(FE)for formate at a wide potential range from-0.5 to-1.1 V,and maintains a great stability catalytic performance without significant decay over 30 h in flow cell.Moreover,membrane electrode assembly(MEA)device with OPBi as catalyst sustains the robust current density of 100 mA cm^(-2)over 50 h,maintaining a formate FE above 90%.In addition,rechargeable Zn-CO_(2)battery presents the peak power density of1.22 mW cm^(-2)with OP-Bi as bifunctional catalyst.The mechanism experiments demonstrate that the high-density grain boundaries of OP-Bi provide more exposed active sites,faster electron transfer capacity,and the stronger intrinsic activity of Bi atoms.In situ spectroscopy and theo retical calculations further elucidate that the unsaturated Bi coordination atoms between the grain boundaries can effectively activate CO_(2)molecules through elongating the C-O bond,and reducing the formation energy barrier of the key intermediate(^(*)OCOH),thereby enhancing the catalytic performance of eCO_(2)RR to formate product.展开更多
Micro molybdenum disulfide was prepared with one-step hydrothermal method;the influence of reactant concentration and temperature on the surface ratio of micro-MoS2 grain was investigated. Raman spectroscopy (Raman), ...Micro molybdenum disulfide was prepared with one-step hydrothermal method;the influence of reactant concentration and temperature on the surface ratio of micro-MoS2 grain was investigated. Raman spectroscopy (Raman), X-ray diffraction (XRD), and Scanning electron microscopy (SEM) were used to characterize the structure, composition and morphology of MoS2. The results show that micro-MoS2 grains were synthesized with one-step hydrothermal synthesis, and the morphology of micro-MoS2 grains is like flower and sphere. The SEM figures indicate that the surface ratio of micro-MoS2 grains is different and also show that the surface ratio of micro-MoS2 grains can be improved by regulating reactant concentration and temperature. This research showed a method to improve the surface ratio of micro-MoS2 grains.展开更多
Grain size,characterized by a combination of grain length,width,and thickness,is one of the major determinants of yield in rice.The present study identified TATA-box binding protein-associated factor 2(TAF2)as an esse...Grain size,characterized by a combination of grain length,width,and thickness,is one of the major determinants of yield in rice.The present study identified TATA-box binding protein-associated factor 2(TAF2)as an essential component regulating transcription and determining grain size in rice.Map-based cloning showed that a G/T substitution in TAF2 resulted in a naturally occurring mutant called reduced grain size and plant height 1(rgh1).The mutants,with weak edited rgh1 alleles,exhibited a small grain phenotype with reduced grain length and width,while the severe knockout mutant(rgh1-2s)was dwarf and completely sterile.Allelic test performed between rgh1 and several edited alleles confirmed that the mutation in TAF2 caused the rgh1 phenotype.GUS staining showed that TAF2 was mainly expressed in the vascular bundles of roots,stems,leaves,and grains.The cytological analysis revealed that reduced cell division in the glumes resulted in the small grain phenotype of rgh1.Further RNA-sequencing detected altered expression of genes involved in the basic biological processes in rgh1 mutant.These findings provide novel insights into the TAF2-mediated genetic mechanism regulating grain size in rice.展开更多
We investigate the effect of ion irradiation on MgB_(2) thin films with small grains of approximately 122 nm and 140 nm.The flux pinning by grain boundaries is insignificant in the pristine MgB_(2) films due to good i...We investigate the effect of ion irradiation on MgB_(2) thin films with small grains of approximately 122 nm and 140 nm.The flux pinning by grain boundaries is insignificant in the pristine MgB_(2) films due to good inter-grain connectivity,but is significantly improved after 120-keV Mn-ion irradiation.The scaling behavior of the flux pinning force density for the ion-irradiated MgB_(2) thin films with nanoscale grains demonstrates the predominance of pinning by grain boundaries,in contrast to the single-crystalline MgB_(2) films where normal point pinning was dominant after low-energy ion irradiation.These results suggest that irradiation-induced defects can accumulate near the grain boundaries in metallic MgB_(2) superconductors.展开更多
Applying iodine fertilizers to cultivate iodine-rich crops for daily intake is an effective approach for iodine supplementation,especially for aromatic rice.Field experiments were conducted during the early growing se...Applying iodine fertilizers to cultivate iodine-rich crops for daily intake is an effective approach for iodine supplementation,especially for aromatic rice.Field experiments were conducted during the early growing seasons of 2021 and 2022 to evaluate the impacts of foliar application of iodine fertilizer on aromatic rice and to explore the optimal iodine fertilizer concentration.At the full heading stage,six different concentrations of sodium iodide solutions of 0%(CK),0.010%(T1),0.025%(T2),0.050%(T3),0.075%(T4),and 0.100%(T5)were applied to indica aromatic rice cultivars Meixiangzhan 2 and Xiangyaxiangzhan.The results showed that sodium iodide treatments significantly increased the iodine and sodium contents in both leaves and grains.Compared with the CK,the T1 and T2 treatments increased the 2-acetyl-1-pyrroline(2-AP)content in mature grains by 8.41%-101.66%and 13.58%-74.60%,respectively.Improvements in the contents of 1-pyrroline-5-carboxylic acid,proline,1-pyrroline,and methylglyoxal,as well as the activity of proline dehydrogenase were also detected.Additionally,sodium iodide treatments remarkably decreased the chalky grain rate,chalkiness area,and chalkiness degree of aromatic rice,with the T2 treatment exhibiting a 17.79%-47.42%decrease in chalkiness degree compared with the CK.Meanwhile,T1 and T2 treatments showed beneficial impacts on chlorophyll content,photosynthetic characteristics,and yield components,while T3,T4,and T5 treatments exhibited adverse effects on leaf and grain yields.The linear discriminant analysis revealed significant differences between treatments.The correlation analysis and piecewise structural equation modeling showed that the iodine and sodium influenced the photosynthetic characteristics and chlorophyll content of the leaves,thereby regulating the 2-AP biosynthesis and yield components,ultimately affecting the 2-AP content and yield.Overall,this study suggests that foliar application of 0.025%sodium iodide is an effective method to enrich the iodine content in rice grains,improve the grain aroma and appearance quality of aromatic rice,without detrimental effects on grain yield.展开更多
Rice-duck co-culture is an integrated farming technology that benefits rice production, grain quality, and ecological sustainability in paddy fields. However, little is known about the effects of rice-duck co-culture ...Rice-duck co-culture is an integrated farming technology that benefits rice production, grain quality, and ecological sustainability in paddy fields. However, little is known about the effects of rice-duck co-culture on enzyme activity involved in the biosynthesis of 2-acetyl-1-pyrroline (2-AP), the volatile that gives fragrant rice its' distinctive and sought-after aroma. The present study aimed to examine the influence of rice-duck co-culture on the photosynthesis, yield, grain quality, rice aroma, and the enzymes involved in 2-acetyl-1-pyrroline biosynthesis in the cultivar Meixiangzhan 2 during the early and late rice growing seasons of 2016 in Guangzhou, China. We compared the rice grown in paddy fields with and without ducks. We found that rice-duck co-culture not only improved the yield and quality of fragrant rice grain, but also promoted the precursors of 2-AP biosynthesis formation and 2-AP accumulation in the grain. Grain 2-AP content in rice-duck co-culture was noticeably increased with 9.60% and 20.81% in early and late seasons, respectively. Proline and pyrroline-5-carboxylic acid (P5C) (precursors of 2-AP biosynthesis) and the activity of enzymes such as proline dehydrogenase (ProDH), ornithine aminotransferase (OAT) and Δ1 pyrroline-5-carboxylic acid synthetase (P5CS) were all improved by 10.15%–12.99%, 32.91%–47.75%, 17.81%–26.71%, 6.25%–21.78%, and 10.58%–38.87% under rice-duck co-culture in both seasons, respectively. Overall, our results suggest that rice-duck co-culture is an environmentally-friendly and sustainable approach to improving rice aroma and grain quality of fragrant rice.展开更多
Grain shape as a major determinant of rice yield and quality is widely believed to be controlled by quantitative trait loci(QTL). We have identified a novel gene 'GS2' to largely regulate grain length and widt...Grain shape as a major determinant of rice yield and quality is widely believed to be controlled by quantitative trait loci(QTL). We have identified a novel gene 'GS2' to largely regulate grain length and width in rice. The GS2 allele in the big-grain rice line ‘CDL’functioned in a dominant manner. In the present study, we employed a chromosome walking strategy in the residual heterozygous lines from recombinant inbred population between cultivar 'R1126' and CDL, and located the GS2 gene in an interval of ~33.2 kb flanked by marker GL2-35-1 and GL2-12 in the long arm of rice chromosome 2. According to genome annotations, three putative gene loci, LOC_Os02g47280, LOC_Os02g47290 and LOC_Os02g47300, exist in this candidate region. In addition, allelic analysis with previously reported genes demonstrated that GS2 was novel for regulating rice grain shape. These results will help promote the cloning and functional characterization of the GS2 gene and further develop linked markers to be used in marker-assisted breeding.展开更多
基金supported by the Hainan Province Science and Technology Special Fund(ZDYF2024SHFZ074,ZDYF2024SHFZ072,ZDYF2022SHFZ299)the National Natural Science Foundation of China(22109035,22202053,52164028,52274297,22309037)+4 种基金the Start-up Research Foundation of Hainan University(KYQD(ZR)-20008,20083,20084,21125,23035)the collaborative Innovation Center of Marine Science and Technology,Hainan University(XTCX2022HYC04,XTCX2022HYC05)the Innovative Research Projects for Graduate Students of Hainan Province(Qhyb2022-89,Qhyb2022-87,Qhys2022-174)the Scientific Research Program Funded by Shaanxi Provincial Education Department(Program No.23JK0439)the specific research fund of The Innovation Platform for Academicians of Hainan Province(YSPTZX202315)。
文摘Bismuth-based catalysts are highly promising for the electrochemical carbon dioxide reduction reaction(eCO_(2)RR)to formate product.However,achieving high activity and selectivity towards formate and ensuring long-term stability remains challenging.This work reports the oxygen plasma inducing strategy to construct the abundant grain boundaries of Bi/BiO_x on ultrathin two-dimensional Bi nanosheets.The oxygen plasma-treated Bi nanosheet(OP-Bi)exhibits over 90%Faradaic efficiency(FE)for formate at a wide potential range from-0.5 to-1.1 V,and maintains a great stability catalytic performance without significant decay over 30 h in flow cell.Moreover,membrane electrode assembly(MEA)device with OPBi as catalyst sustains the robust current density of 100 mA cm^(-2)over 50 h,maintaining a formate FE above 90%.In addition,rechargeable Zn-CO_(2)battery presents the peak power density of1.22 mW cm^(-2)with OP-Bi as bifunctional catalyst.The mechanism experiments demonstrate that the high-density grain boundaries of OP-Bi provide more exposed active sites,faster electron transfer capacity,and the stronger intrinsic activity of Bi atoms.In situ spectroscopy and theo retical calculations further elucidate that the unsaturated Bi coordination atoms between the grain boundaries can effectively activate CO_(2)molecules through elongating the C-O bond,and reducing the formation energy barrier of the key intermediate(^(*)OCOH),thereby enhancing the catalytic performance of eCO_(2)RR to formate product.
文摘Micro molybdenum disulfide was prepared with one-step hydrothermal method;the influence of reactant concentration and temperature on the surface ratio of micro-MoS2 grain was investigated. Raman spectroscopy (Raman), X-ray diffraction (XRD), and Scanning electron microscopy (SEM) were used to characterize the structure, composition and morphology of MoS2. The results show that micro-MoS2 grains were synthesized with one-step hydrothermal synthesis, and the morphology of micro-MoS2 grains is like flower and sphere. The SEM figures indicate that the surface ratio of micro-MoS2 grains is different and also show that the surface ratio of micro-MoS2 grains can be improved by regulating reactant concentration and temperature. This research showed a method to improve the surface ratio of micro-MoS2 grains.
基金supported by the National Natural Science Foundation of China(31971918 and 32070348)the Chinese Academy of Sciences Innovation Project(XDA24010402).
文摘Grain size,characterized by a combination of grain length,width,and thickness,is one of the major determinants of yield in rice.The present study identified TATA-box binding protein-associated factor 2(TAF2)as an essential component regulating transcription and determining grain size in rice.Map-based cloning showed that a G/T substitution in TAF2 resulted in a naturally occurring mutant called reduced grain size and plant height 1(rgh1).The mutants,with weak edited rgh1 alleles,exhibited a small grain phenotype with reduced grain length and width,while the severe knockout mutant(rgh1-2s)was dwarf and completely sterile.Allelic test performed between rgh1 and several edited alleles confirmed that the mutation in TAF2 caused the rgh1 phenotype.GUS staining showed that TAF2 was mainly expressed in the vascular bundles of roots,stems,leaves,and grains.The cytological analysis revealed that reduced cell division in the glumes resulted in the small grain phenotype of rgh1.Further RNA-sequencing detected altered expression of genes involved in the basic biological processes in rgh1 mutant.These findings provide novel insights into the TAF2-mediated genetic mechanism regulating grain size in rice.
基金the support of the accelerator group and operators of KOMAC (KAERI (C.K.,J.S.))Project supported by the National Research Foundation (NRF)of Korea through a grant funded by the Korean Ministry of Science and ICT (Grant No.2021R1A2C2010925 (T.P.,Y.H.,J.S.))+2 种基金the Basic Science Research Program through the NRF of Korea funded by the Ministry of Education (Grant Nos.NRF-2019R1F1A1055284 (J.M.L.,W.N.K.)and NRF2021R1I1A1A01043885 (S.G.J.,Y.H.))the National Natural Science Foundation of China (Grant Nos.12035019 (J.L.))the Chinese Scholarship Council (CSC)for fellowship support。
文摘We investigate the effect of ion irradiation on MgB_(2) thin films with small grains of approximately 122 nm and 140 nm.The flux pinning by grain boundaries is insignificant in the pristine MgB_(2) films due to good inter-grain connectivity,but is significantly improved after 120-keV Mn-ion irradiation.The scaling behavior of the flux pinning force density for the ion-irradiated MgB_(2) thin films with nanoscale grains demonstrates the predominance of pinning by grain boundaries,in contrast to the single-crystalline MgB_(2) films where normal point pinning was dominant after low-energy ion irradiation.These results suggest that irradiation-induced defects can accumulate near the grain boundaries in metallic MgB_(2) superconductors.
基金supported by the National Natural Science Foundation of China(Grant No.31971843)the Technology System of Modern Agricultural Industry in Guangdong Province,China(Grant No.2020KJ105)+1 种基金the Guangzhou Science and Technology Project,Guangdong Province,China(Grant No.202103000075)the Special Rural Revitalization Funds of Guangdong Province,China(Grant No.2021KJ382)。
文摘Applying iodine fertilizers to cultivate iodine-rich crops for daily intake is an effective approach for iodine supplementation,especially for aromatic rice.Field experiments were conducted during the early growing seasons of 2021 and 2022 to evaluate the impacts of foliar application of iodine fertilizer on aromatic rice and to explore the optimal iodine fertilizer concentration.At the full heading stage,six different concentrations of sodium iodide solutions of 0%(CK),0.010%(T1),0.025%(T2),0.050%(T3),0.075%(T4),and 0.100%(T5)were applied to indica aromatic rice cultivars Meixiangzhan 2 and Xiangyaxiangzhan.The results showed that sodium iodide treatments significantly increased the iodine and sodium contents in both leaves and grains.Compared with the CK,the T1 and T2 treatments increased the 2-acetyl-1-pyrroline(2-AP)content in mature grains by 8.41%-101.66%and 13.58%-74.60%,respectively.Improvements in the contents of 1-pyrroline-5-carboxylic acid,proline,1-pyrroline,and methylglyoxal,as well as the activity of proline dehydrogenase were also detected.Additionally,sodium iodide treatments remarkably decreased the chalky grain rate,chalkiness area,and chalkiness degree of aromatic rice,with the T2 treatment exhibiting a 17.79%-47.42%decrease in chalkiness degree compared with the CK.Meanwhile,T1 and T2 treatments showed beneficial impacts on chlorophyll content,photosynthetic characteristics,and yield components,while T3,T4,and T5 treatments exhibited adverse effects on leaf and grain yields.The linear discriminant analysis revealed significant differences between treatments.The correlation analysis and piecewise structural equation modeling showed that the iodine and sodium influenced the photosynthetic characteristics and chlorophyll content of the leaves,thereby regulating the 2-AP biosynthesis and yield components,ultimately affecting the 2-AP content and yield.Overall,this study suggests that foliar application of 0.025%sodium iodide is an effective method to enrich the iodine content in rice grains,improve the grain aroma and appearance quality of aromatic rice,without detrimental effects on grain yield.
基金supported by the Science and Technology Project of Guangdong Province (2015B090903077, 2016A020210094, 2017A090905030), Chinathe Science and Technology Project of Guangzhou (201604020062), China+1 种基金the Innovation Team Construction Project of Modern Agricultural Industry Technology System of Guangdong Province (2016LM1100), Chinathe Overseas Joint Doctoral Training Program of South China Agricultural University (2018LHPY010), China
文摘Rice-duck co-culture is an integrated farming technology that benefits rice production, grain quality, and ecological sustainability in paddy fields. However, little is known about the effects of rice-duck co-culture on enzyme activity involved in the biosynthesis of 2-acetyl-1-pyrroline (2-AP), the volatile that gives fragrant rice its' distinctive and sought-after aroma. The present study aimed to examine the influence of rice-duck co-culture on the photosynthesis, yield, grain quality, rice aroma, and the enzymes involved in 2-acetyl-1-pyrroline biosynthesis in the cultivar Meixiangzhan 2 during the early and late rice growing seasons of 2016 in Guangzhou, China. We compared the rice grown in paddy fields with and without ducks. We found that rice-duck co-culture not only improved the yield and quality of fragrant rice grain, but also promoted the precursors of 2-AP biosynthesis formation and 2-AP accumulation in the grain. Grain 2-AP content in rice-duck co-culture was noticeably increased with 9.60% and 20.81% in early and late seasons, respectively. Proline and pyrroline-5-carboxylic acid (P5C) (precursors of 2-AP biosynthesis) and the activity of enzymes such as proline dehydrogenase (ProDH), ornithine aminotransferase (OAT) and Δ1 pyrroline-5-carboxylic acid synthetase (P5CS) were all improved by 10.15%–12.99%, 32.91%–47.75%, 17.81%–26.71%, 6.25%–21.78%, and 10.58%–38.87% under rice-duck co-culture in both seasons, respectively. Overall, our results suggest that rice-duck co-culture is an environmentally-friendly and sustainable approach to improving rice aroma and grain quality of fragrant rice.
基金supported by the National High Technology Research and Development Program of China (2011AA10A101)the Hunan Provincial Natural Science Foundation of China (10JJ2025)
文摘Grain shape as a major determinant of rice yield and quality is widely believed to be controlled by quantitative trait loci(QTL). We have identified a novel gene 'GS2' to largely regulate grain length and width in rice. The GS2 allele in the big-grain rice line ‘CDL’functioned in a dominant manner. In the present study, we employed a chromosome walking strategy in the residual heterozygous lines from recombinant inbred population between cultivar 'R1126' and CDL, and located the GS2 gene in an interval of ~33.2 kb flanked by marker GL2-35-1 and GL2-12 in the long arm of rice chromosome 2. According to genome annotations, three putative gene loci, LOC_Os02g47280, LOC_Os02g47290 and LOC_Os02g47300, exist in this candidate region. In addition, allelic analysis with previously reported genes demonstrated that GS2 was novel for regulating rice grain shape. These results will help promote the cloning and functional characterization of the GS2 gene and further develop linked markers to be used in marker-assisted breeding.