Cryptromeria fortunei is one of the main forest plantation species in the subtropical high altitude areas in China. In this paper we collected 49 C. fortunei germplasm resources and provides a study of the utility of ...Cryptromeria fortunei is one of the main forest plantation species in the subtropical high altitude areas in China. In this paper we collected 49 C. fortunei germplasm resources and provides a study of the utility of freely available C. japonica EST resources for the development of markers necessary for genetic diversity analyses of C. fortunei. By screening 24,299 EST sequences from C. japonica with SSR Finder, we identified 2384 ESTs car- rying 2783 SSR motifs. We successfully obtained 364 （15 %） primers from 2419 putative SSR loci. Of the 80 candidate SSR markers tested, 70 （87.5 %） yielded stable and clear PCR products. With those primers, the genetic diversity of 49 C. fortunei we collected was studied. The results showed that 18 primers yield polymorphism within these accessions. These 18 primers generated 48 scorable SSR loci and the average number of polymorphic SSR loci per primer was 2.7. The PIC value varied from 0.375 to 0.8101, with the average of 0.4780. The Shannon index is 0.5718, and the value of the observed number of alleles and effective number of alleles are 1.9167 and 1.7289, respectively. The genetic coefficient of these 49 accessions varied from 0.28 to 0.87. According to the genetic dis- tances, a cluster tree was constructed. At genetic coefficient of 0.60, these 49 accessions can group into 3： group I contains only FJ-laizhou accession, and group II contains 2accessions from FJ-layang, and the other one group con- tains mixed accessions. At genetic coefficient of 0.68, the former group II was constructed into 7 subgroups, with the first 3 subgroups contain 16 accessions in which 11 （69 %） are from Fujian province, and the later 4 subgroup contain 31 accessions in which 20 （65 %） were from Zhejiang province.展开更多
The development of a rapid, robust and reliable method for extracting plant food materials is important for screening a wide range of plant bioactives for their health benefits. In this study, extractions of bioactive...The development of a rapid, robust and reliable method for extracting plant food materials is important for screening a wide range of plant bioactives for their health benefits. In this study, extractions of bioactive polyphenolic com-pounds from fruits and vegetables were per-formed using a pressurised solvent extraction technique. Variables including solvent, extrac-tion temperature and time, and number of ex-traction cycles, were optimised to develop a rapid and efficient extraction protocol. The re-sulting extracts were then analysed for antioxi-dant capacity, total phenolic content and com-position. The optimal parameters found were 19:1 methanol/water (95% methanol) as solvent and three extraction cycles, of 10 minutes at 40oC or 2 minutes at 100oC. High performance liquid chromatography mass spectrometry did not detect any difference in extract composition between low and high temperatures. Extraction at 100°C generally gave a moderately higher yield of polyphenolics for some fruit and vege-table extracts but appeared to reduce the anti-oxidant activity particularly for turnip leaf, el-derberry and sour cherry extracts as measured by oxygen radical absorbance capacity assay. We found that all 40°C extracts were better at protecting cells from H2O2-induced cellular damage than their 100°C counterparts. The 40°C apple puree and elderberry extracts were about 2 fold and 1.7 fold more effective, respectively, than extracts prepared at 100°C. Our results demonstrated that pressurised solvent extrac-tion technique with careful parameter selection can be used as a quick method for screening the health benefits of plant food materials.展开更多
The impact of interfacial charge on catalytic performance of supported-metal-cluster(SMC)heterostructures remains unclear,hindering efforts to develop high-performance SMC catalysts.Herein we systematically investigat...The impact of interfacial charge on catalytic performance of supported-metal-cluster(SMC)heterostructures remains unclear,hindering efforts to develop high-performance SMC catalysts.Herein we systematically investigated interfacial charge effects of SMCs using a model system of graphene-supported gold-nanoclusters(AuNCs/rGO)for azo hydrogenation.Three types of SMCs with different interfacial charges were synthesized by anchoring electropositive 2-aminoethanethiol(CSH),amphoteric cysteine(Cys),and electronegative 3-mercaptopropionic-acid(MPA)onto AuNCs/rGO,respectively.All three SMCs exhibited high and selective catalytic activity to azo-hydrogenation in four representative azo dyes.The catalytic activity of Cys@AuNCs/rGO was lower than that of CSH@AuNCs/rGO but higher than that of MPA@AuNCs/rGO.However,the cyclic stability of Cys@AuNCs/rGO was inferior to that of both CSH@AuNCs/rGO and MPA@AuNCs/rGO.Further mechanistic studies revealed that amino ligands modified CSH@AuNCs and Cys@AuNCs agglomerated into large-size gold nanoparticles on rGO surface during catalytic reaction under NaBH_(4) action,leading to reduced efficiency and cyclic stability.Conversely,non-amino ligand modified MPA@AuNCs only partially detached from rGO surface without agglomeration,resulting in better cyclic stability.Protection of amino groups in ligands such as modifying-NH_(3)^(+)group in Cys into imine to form N-isobutyryl-L-cysteine(NIBC)substantially improved the cyclic stability while maintaining the high activity in the NIBC@AuNCs/rGO catalyst system.Our work provides an approach for developing a highly-active and stable SMC heterostructure catalyst via manipulating interfacial charges in SMC.展开更多
Porous carbons （PC） were prepared from a waste biomass named chestnut shell via a two-step method involving carbonization and KOH activation. The morphology, pore structure and surface chemical properties were inves...Porous carbons （PC） were prepared from a waste biomass named chestnut shell via a two-step method involving carbonization and KOH activation. The morphology, pore structure and surface chemical properties were investigated by scanning electron microscopy （SEM）, N2 sorption, Raman spectroscopy, X-ray diffraction （XRD） and X-ray photoelectron spectroscopy （XPS）. The carbons have been evaluated as the electrode materials for supercapacitors by a two-electrode system in 6 mol/L KOH electrolyte. Benefiting from the porous texture, high surface area and high oxygen content, the PCs derived from chestnut shell have exhibited high specific capacitance of 198.2 （PC-l）, 217.2 （PC-2） and 238.2 F·g^-1 （PC-3） at a current density of 0.1 Aog l, good rate capability of 55.7%, 56.6% and 54.9% in a range of 0.1 -20 A·g^-1 and high energy density of 5.6, 6.1 and 6.7 Wh·kg^-1, respectively. This is believed to be due to electric double layer capacitance induced by the abundant micropores and extra pseudo-capacitance generated by oxygen-containing groups. At a power density of 9000 Wh·kg^-1, the energy density is 3.1, 3.5 and 3.7 Whokg 1 for PC-l, PC-2 and PC-3, respectively, demonstrating the potential of the carbons derived from chestnut shells in energy storage devices.展开更多
By using tetrathiafulvalene as reducing and doping agents, three-dimensional （3D） sulfur-doped graphene hydrogels （SGHs） were facilely prepared in mixed solvents of dimethyl formamide and water. Several investigat...By using tetrathiafulvalene as reducing and doping agents, three-dimensional （3D） sulfur-doped graphene hydrogels （SGHs） were facilely prepared in mixed solvents of dimethyl formamide and water. Several investigations reveal that TTF plays a critical role in the formation of such unique 3D architecture, as it not only reduces GO to self-assembly into 3D structures, but also can be transformed to TTF^·＋ and TTF^2＋ as doping agents in the reduction process. The morphology, crystal structure, chemical bonding, elemental composition and porosity of the as-prepared SGHs have been studied. Benefiting from well-defined and cross-linked 3D porous network architectures, the supercapacitors based on the SGHs in KOH 212.5 F·g^-1 at 0.3 A·g^-1. Furthermore, this capacitance also degree of reversibility in the repetitive charge/discharge cycling electrolyte exhibited a high specific capacitance of showed good electrochemical stability and a high test.展开更多
Maize(Zea mays)requires substantial amounts of nitrogen,posing a challenge for its cultivation.Recent work discovered that some ancient Mexican maize landraces harbored diazotrophic bacteria in mucilage secreted by th...Maize(Zea mays)requires substantial amounts of nitrogen,posing a challenge for its cultivation.Recent work discovered that some ancient Mexican maize landraces harbored diazotrophic bacteria in mucilage secreted by their aerial roots.To see if this trait is retained in modern maize,we conducted a field study of aerial root mucilage(ARM)in 258 inbred lines.We observed that ARM secretion is common in modern maize,but the amount significantly varies,and only a few lines have retained the nitrogen‐fixing traits found in ancient landraces.The mucilage of the high‐ARM inbred line HN5‐724 had high nitrogen‐fixing enzyme activity and abundant diazotrophic bacteria.Our genome‐wide association study identified 17 candidate genes associated with ARM across three environments.Knockouts of one candidate gene,the subtilase family gene ZmSBT3,confirmed that it negatively regulates ARM secretion.Notably,the ZmSBT3 knockout lines had increased biomass and total nitrogen accumulation under nitrogen‐free culture conditions.High ARM was associated with three ZmSBT3 haplotypes that were gradually lost during maize domestication,being retained in only a few modern inbred lines such as HN5‐724.In summary,our results identify ZmSBT3 as a potential tool for enhancing ARM,and thus nitrogen fixation,in maize.展开更多
文摘Cryptromeria fortunei is one of the main forest plantation species in the subtropical high altitude areas in China. In this paper we collected 49 C. fortunei germplasm resources and provides a study of the utility of freely available C. japonica EST resources for the development of markers necessary for genetic diversity analyses of C. fortunei. By screening 24,299 EST sequences from C. japonica with SSR Finder, we identified 2384 ESTs car- rying 2783 SSR motifs. We successfully obtained 364 （15 %） primers from 2419 putative SSR loci. Of the 80 candidate SSR markers tested, 70 （87.5 %） yielded stable and clear PCR products. With those primers, the genetic diversity of 49 C. fortunei we collected was studied. The results showed that 18 primers yield polymorphism within these accessions. These 18 primers generated 48 scorable SSR loci and the average number of polymorphic SSR loci per primer was 2.7. The PIC value varied from 0.375 to 0.8101, with the average of 0.4780. The Shannon index is 0.5718, and the value of the observed number of alleles and effective number of alleles are 1.9167 and 1.7289, respectively. The genetic coefficient of these 49 accessions varied from 0.28 to 0.87. According to the genetic dis- tances, a cluster tree was constructed. At genetic coefficient of 0.60, these 49 accessions can group into 3： group I contains only FJ-laizhou accession, and group II contains 2accessions from FJ-layang, and the other one group con- tains mixed accessions. At genetic coefficient of 0.68, the former group II was constructed into 7 subgroups, with the first 3 subgroups contain 16 accessions in which 11 （69 %） are from Fujian province, and the later 4 subgroup contain 31 accessions in which 20 （65 %） were from Zhejiang province.
文摘The development of a rapid, robust and reliable method for extracting plant food materials is important for screening a wide range of plant bioactives for their health benefits. In this study, extractions of bioactive polyphenolic com-pounds from fruits and vegetables were per-formed using a pressurised solvent extraction technique. Variables including solvent, extrac-tion temperature and time, and number of ex-traction cycles, were optimised to develop a rapid and efficient extraction protocol. The re-sulting extracts were then analysed for antioxi-dant capacity, total phenolic content and com-position. The optimal parameters found were 19:1 methanol/water (95% methanol) as solvent and three extraction cycles, of 10 minutes at 40oC or 2 minutes at 100oC. High performance liquid chromatography mass spectrometry did not detect any difference in extract composition between low and high temperatures. Extraction at 100°C generally gave a moderately higher yield of polyphenolics for some fruit and vege-table extracts but appeared to reduce the anti-oxidant activity particularly for turnip leaf, el-derberry and sour cherry extracts as measured by oxygen radical absorbance capacity assay. We found that all 40°C extracts were better at protecting cells from H2O2-induced cellular damage than their 100°C counterparts. The 40°C apple puree and elderberry extracts were about 2 fold and 1.7 fold more effective, respectively, than extracts prepared at 100°C. Our results demonstrated that pressurised solvent extrac-tion technique with careful parameter selection can be used as a quick method for screening the health benefits of plant food materials.
基金supported by the National Natural Science Foundation of China(Nos.52273110,21975191,52372271,22173070)the Knowledge Innovation Program of Wuhan Shuguang Project,and the Fundamental Research Funds for the Central Universities(WUT:2023Ⅲ013GX).
文摘The impact of interfacial charge on catalytic performance of supported-metal-cluster(SMC)heterostructures remains unclear,hindering efforts to develop high-performance SMC catalysts.Herein we systematically investigated interfacial charge effects of SMCs using a model system of graphene-supported gold-nanoclusters(AuNCs/rGO)for azo hydrogenation.Three types of SMCs with different interfacial charges were synthesized by anchoring electropositive 2-aminoethanethiol(CSH),amphoteric cysteine(Cys),and electronegative 3-mercaptopropionic-acid(MPA)onto AuNCs/rGO,respectively.All three SMCs exhibited high and selective catalytic activity to azo-hydrogenation in four representative azo dyes.The catalytic activity of Cys@AuNCs/rGO was lower than that of CSH@AuNCs/rGO but higher than that of MPA@AuNCs/rGO.However,the cyclic stability of Cys@AuNCs/rGO was inferior to that of both CSH@AuNCs/rGO and MPA@AuNCs/rGO.Further mechanistic studies revealed that amino ligands modified CSH@AuNCs and Cys@AuNCs agglomerated into large-size gold nanoparticles on rGO surface during catalytic reaction under NaBH_(4) action,leading to reduced efficiency and cyclic stability.Conversely,non-amino ligand modified MPA@AuNCs only partially detached from rGO surface without agglomeration,resulting in better cyclic stability.Protection of amino groups in ligands such as modifying-NH_(3)^(+)group in Cys into imine to form N-isobutyryl-L-cysteine(NIBC)substantially improved the cyclic stability while maintaining the high activity in the NIBC@AuNCs/rGO catalyst system.Our work provides an approach for developing a highly-active and stable SMC heterostructure catalyst via manipulating interfacial charges in SMC.
基金We are grateful for the financial support from the National Natural Science Foundation of China （Nos. 21402108, 21476132, 51302156 and 21576158）, the Natural Science Foundation of Shandong Province （No. ZR2014BQ036） and the Young Teacher Supporting Fund of Shandong University of Technology.
文摘Porous carbons （PC） were prepared from a waste biomass named chestnut shell via a two-step method involving carbonization and KOH activation. The morphology, pore structure and surface chemical properties were investigated by scanning electron microscopy （SEM）, N2 sorption, Raman spectroscopy, X-ray diffraction （XRD） and X-ray photoelectron spectroscopy （XPS）. The carbons have been evaluated as the electrode materials for supercapacitors by a two-electrode system in 6 mol/L KOH electrolyte. Benefiting from the porous texture, high surface area and high oxygen content, the PCs derived from chestnut shell have exhibited high specific capacitance of 198.2 （PC-l）, 217.2 （PC-2） and 238.2 F·g^-1 （PC-3） at a current density of 0.1 Aog l, good rate capability of 55.7%, 56.6% and 54.9% in a range of 0.1 -20 A·g^-1 and high energy density of 5.6, 6.1 and 6.7 Wh·kg^-1, respectively. This is believed to be due to electric double layer capacitance induced by the abundant micropores and extra pseudo-capacitance generated by oxygen-containing groups. At a power density of 9000 Wh·kg^-1, the energy density is 3.1, 3.5 and 3.7 Whokg 1 for PC-l, PC-2 and PC-3, respectively, demonstrating the potential of the carbons derived from chestnut shells in energy storage devices.
基金Acknowledgement We are grateful for the financial support from the National Natural Science Foundation of China （Nos. 21402108, 21476132, 51302156, 21576158 and 21576159） and Shandong Natural Science Foundation （No. ZR2014BQ036）.
文摘By using tetrathiafulvalene as reducing and doping agents, three-dimensional （3D） sulfur-doped graphene hydrogels （SGHs） were facilely prepared in mixed solvents of dimethyl formamide and water. Several investigations reveal that TTF plays a critical role in the formation of such unique 3D architecture, as it not only reduces GO to self-assembly into 3D structures, but also can be transformed to TTF^·＋ and TTF^2＋ as doping agents in the reduction process. The morphology, crystal structure, chemical bonding, elemental composition and porosity of the as-prepared SGHs have been studied. Benefiting from well-defined and cross-linked 3D porous network architectures, the supercapacitors based on the SGHs in KOH 212.5 F·g^-1 at 0.3 A·g^-1. Furthermore, this capacitance also degree of reversibility in the repetitive charge/discharge cycling electrolyte exhibited a high specific capacitance of showed good electrochemical stability and a high test.
基金the special fund at Henan Agricultural University
文摘Maize(Zea mays)requires substantial amounts of nitrogen,posing a challenge for its cultivation.Recent work discovered that some ancient Mexican maize landraces harbored diazotrophic bacteria in mucilage secreted by their aerial roots.To see if this trait is retained in modern maize,we conducted a field study of aerial root mucilage(ARM)in 258 inbred lines.We observed that ARM secretion is common in modern maize,but the amount significantly varies,and only a few lines have retained the nitrogen‐fixing traits found in ancient landraces.The mucilage of the high‐ARM inbred line HN5‐724 had high nitrogen‐fixing enzyme activity and abundant diazotrophic bacteria.Our genome‐wide association study identified 17 candidate genes associated with ARM across three environments.Knockouts of one candidate gene,the subtilase family gene ZmSBT3,confirmed that it negatively regulates ARM secretion.Notably,the ZmSBT3 knockout lines had increased biomass and total nitrogen accumulation under nitrogen‐free culture conditions.High ARM was associated with three ZmSBT3 haplotypes that were gradually lost during maize domestication,being retained in only a few modern inbred lines such as HN5‐724.In summary,our results identify ZmSBT3 as a potential tool for enhancing ARM,and thus nitrogen fixation,in maize.
