Covalent organic frameworks(COFs)are considered promising catalysts for photocatalytic CO_(2)reduction reaction(pCO_(2)RR)due to facilitated regulations.However,the instability of COFs with dynamic reversible covalent...Covalent organic frameworks(COFs)are considered promising catalysts for photocatalytic CO_(2)reduction reaction(pCO_(2)RR)due to facilitated regulations.However,the instability of COFs with dynamic reversible covalent bonds and the limited modifiability of COFs with irreversible covalent bonds restricted the enhancement of the pCO_(2)RR performance.Herein,three phthalocyanine-based COFs with ether-linked,CoOP,CoPOP,and CoBOP,were successfully prepared via in situ polycondensation using modifiable bis-phthalonitrile.CoBOP achieved a record of syngas performance in pCO_(2)RR systems with photosensitizers and sacrificial agents(CO 83.7 mmol g^(-1)h^(-1)and H_254.7 mmol g^(-1)h^(-1)),surpassing most COF photocatalysts.Additionally,CoOP,CoPOP,and CoBOP exhibit stabilities in extreme environments owing to their irreversible covalent bonds.Experimental and density functional theory analyses confirm that the optimally matched the lowest unoccupied molecular orbital of the linking unit between the photosensitizer and active unit endowed Co BOP with the highest photoelectron transfer efficiency among the three catalysts,boosting its pCO_(2)RR activity.This work is highly instructive for designing COFs with structure-adjustable and irreversible covalent bonds.展开更多
Although Quercus mongolica is a widely distributed,economically and ecologically important deciduous tree in northern China,models to accurately predict stand growth at a regional scale are limited.The physiological p...Although Quercus mongolica is a widely distributed,economically and ecologically important deciduous tree in northern China,models to accurately predict stand growth at a regional scale are limited.The physiological process model(3-PG)has the potential to predict stand growth dynamics under varying site conditions and climate change scenarios.Here,we used field inventory,tree ring sampling,and Bayesian calibration to parameterize a model for Q.mongolica.Stand volume and productivity were then predicted under present conditions and three future climate scenarios(RCP26,RCP45 and RCP85).Our results demonstrated that after Bayesian calibration,the posterior ranges of the sensitivity parameters apha Cx,wSx1000 and pRn accounted for 34%,45%and 65%,respectively,of their prior range.Calibration and validation results revealed a strong correlation between predicted and measured values(R^(2)>0.87,P<0.01),with<20%bias for all growth indicators.Stand volume was projected to increase by 145%and productivity by 80%by the year 2100 under the RCP85 scenario,although these projections may vary across regions.The present study developed a tailored set of 3-PG model parameters for Q.mongolica,based on a comprehensive range of climate conditions,stand structure,and age classes.These parameters offer a scientific basis to accurately predict growth of other monospecific oak or mixed-species stands.展开更多
The genus Thuja is ideal for investigating the genetic basis of the East Asia-North America disjunction.The biogeographical background of the genus is debatable and an adaptive strategy is lacking.Through the analysis...The genus Thuja is ideal for investigating the genetic basis of the East Asia-North America disjunction.The biogeographical background of the genus is debatable and an adaptive strategy is lacking.Through the analysis and mining of comparative transcriptomes,species differentiation and positively selected genes(PSGs)were identified to provide information for understanding the environmental adaptation strategies of the genus Thuja.De novo assembly yielded 44,397-74,252 unigenes of the five Thuja species with contig N50length ranging from 1,559 to 1,724 bp.Annotations revealed a similar distribution of functional categories among them.Based on the phylogenetic trees constructed using the transcriptome data,T.sutchuenensis was divided first,followed by T.plicata and T.occidentalis.The final differentiation of T.koraiensis and T.standishii formed a clade.Enrichment analysis indicated that the PSGs of the North American Thuja species were involved in plant hormone signal transduction and carbon fixation of photosynthetic organisms pathways.The PSGs of East Asian Thuja were related to phenolic,alkaloid,and terpenoid synthesis,important stress-resistant genes and could increase plant resistance to external environmental stresses.This study discovered numerous aroma synthetic-related PSGs including terpene synthase(TPS)genes and lipid phosphate phosphatase 2(LPP2),associated with the synthetic aroma of T.sutchuenensis.Physiological indicators,such as the contents of soluble sugars,total chlorophyll,total phenolics,and total flavonoids were determined,which are consistent with the PSGs enrichment pathways associated with adaptive strategies in the five Thuja species.The results of this study provide an important basis for future studies on conservation genetics.展开更多
Nickel-CeO_(2)-based materials are commonly used for the thermal catalytic hydrogenation of CO_(2).However,high Ni loadings and low CO selectivity restrict their use in the reverse water–gas shift(RWGS)reaction.Herei...Nickel-CeO_(2)-based materials are commonly used for the thermal catalytic hydrogenation of CO_(2).However,high Ni loadings and low CO selectivity restrict their use in the reverse water–gas shift(RWGS)reaction.Herein,we demonstrate a highly active,robust,and low-Ni-doped(1.1 wt.%)CeO_(2) catalyst(1.0-Ni-CeO_(2)).The Ni-based-mass-specific CO formation rate reaches up to 1,542 mmol·gNi^(−1)·h^(−1) with 100%CO selectivity at 300°C for 100 h,among the best values reported in the literature.Density functional theory(DFT)and diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)results reveal that the enhanced catalytic activity is attributed to the abundant Ce–H species,while the high selectivity results from low CO affinity.More importantly,a new reaction mechanism is proposed,which involves the reduction of bicarbonate to generate formate intermediate and CO by the H−released from Ce–H species.The new findings in this work will benefit the design of economic,efficient,and robust catalysts for low-temperature RWGS reactions.展开更多
基金financially supported by the Innovation Capability Support Program of Shaanxi—Science and Technology Innovation Team Project(No.2025RS-CXTD-024)the Fundamental Research Foundation of SHCCIG New Materials Technology Research Institute Co.,Ltd(No.D5204230171)+3 种基金the Fundamental Research Funds for the Central Universities(G2025KY05240)the Natural Science Basic Research Program of Shaanxi(Program No.2024JC-YBQN-0073)the Fundamental Research Funds for the Central Universities(No.D5000250204)Young Talent Fund of Association for Science and Technology in Shaanxi(No.20230101)。
文摘Covalent organic frameworks(COFs)are considered promising catalysts for photocatalytic CO_(2)reduction reaction(pCO_(2)RR)due to facilitated regulations.However,the instability of COFs with dynamic reversible covalent bonds and the limited modifiability of COFs with irreversible covalent bonds restricted the enhancement of the pCO_(2)RR performance.Herein,three phthalocyanine-based COFs with ether-linked,CoOP,CoPOP,and CoBOP,were successfully prepared via in situ polycondensation using modifiable bis-phthalonitrile.CoBOP achieved a record of syngas performance in pCO_(2)RR systems with photosensitizers and sacrificial agents(CO 83.7 mmol g^(-1)h^(-1)and H_254.7 mmol g^(-1)h^(-1)),surpassing most COF photocatalysts.Additionally,CoOP,CoPOP,and CoBOP exhibit stabilities in extreme environments owing to their irreversible covalent bonds.Experimental and density functional theory analyses confirm that the optimally matched the lowest unoccupied molecular orbital of the linking unit between the photosensitizer and active unit endowed Co BOP with the highest photoelectron transfer efficiency among the three catalysts,boosting its pCO_(2)RR activity.This work is highly instructive for designing COFs with structure-adjustable and irreversible covalent bonds.
基金supported by the Fundamental Research Funds for the Central Non-profit Research Institution of CAF(CAFYBB2022ZA001)the National Natural Science Foundation of China(42071065)。
文摘Although Quercus mongolica is a widely distributed,economically and ecologically important deciduous tree in northern China,models to accurately predict stand growth at a regional scale are limited.The physiological process model(3-PG)has the potential to predict stand growth dynamics under varying site conditions and climate change scenarios.Here,we used field inventory,tree ring sampling,and Bayesian calibration to parameterize a model for Q.mongolica.Stand volume and productivity were then predicted under present conditions and three future climate scenarios(RCP26,RCP45 and RCP85).Our results demonstrated that after Bayesian calibration,the posterior ranges of the sensitivity parameters apha Cx,wSx1000 and pRn accounted for 34%,45%and 65%,respectively,of their prior range.Calibration and validation results revealed a strong correlation between predicted and measured values(R^(2)>0.87,P<0.01),with<20%bias for all growth indicators.Stand volume was projected to increase by 145%and productivity by 80%by the year 2100 under the RCP85 scenario,although these projections may vary across regions.The present study developed a tailored set of 3-PG model parameters for Q.mongolica,based on a comprehensive range of climate conditions,stand structure,and age classes.These parameters offer a scientific basis to accurately predict growth of other monospecific oak or mixed-species stands.
基金supported by the National Natural Science Foundation of China(31870664)the 948 Program of National Forestry and Grassland Administration(2013-4-47)the National Key Research and Development Program of China(2022YFD2200103)。
文摘The genus Thuja is ideal for investigating the genetic basis of the East Asia-North America disjunction.The biogeographical background of the genus is debatable and an adaptive strategy is lacking.Through the analysis and mining of comparative transcriptomes,species differentiation and positively selected genes(PSGs)were identified to provide information for understanding the environmental adaptation strategies of the genus Thuja.De novo assembly yielded 44,397-74,252 unigenes of the five Thuja species with contig N50length ranging from 1,559 to 1,724 bp.Annotations revealed a similar distribution of functional categories among them.Based on the phylogenetic trees constructed using the transcriptome data,T.sutchuenensis was divided first,followed by T.plicata and T.occidentalis.The final differentiation of T.koraiensis and T.standishii formed a clade.Enrichment analysis indicated that the PSGs of the North American Thuja species were involved in plant hormone signal transduction and carbon fixation of photosynthetic organisms pathways.The PSGs of East Asian Thuja were related to phenolic,alkaloid,and terpenoid synthesis,important stress-resistant genes and could increase plant resistance to external environmental stresses.This study discovered numerous aroma synthetic-related PSGs including terpene synthase(TPS)genes and lipid phosphate phosphatase 2(LPP2),associated with the synthetic aroma of T.sutchuenensis.Physiological indicators,such as the contents of soluble sugars,total chlorophyll,total phenolics,and total flavonoids were determined,which are consistent with the PSGs enrichment pathways associated with adaptive strategies in the five Thuja species.The results of this study provide an important basis for future studies on conservation genetics.
基金the Science and Technology Project of Shenzhen(No.JCYJ20190806155814624)the National Natural Science Foundation of China(No.22002120)the Fundamental Research Funds for the Central Universities(No.3102017jc01001).
文摘Nickel-CeO_(2)-based materials are commonly used for the thermal catalytic hydrogenation of CO_(2).However,high Ni loadings and low CO selectivity restrict their use in the reverse water–gas shift(RWGS)reaction.Herein,we demonstrate a highly active,robust,and low-Ni-doped(1.1 wt.%)CeO_(2) catalyst(1.0-Ni-CeO_(2)).The Ni-based-mass-specific CO formation rate reaches up to 1,542 mmol·gNi^(−1)·h^(−1) with 100%CO selectivity at 300°C for 100 h,among the best values reported in the literature.Density functional theory(DFT)and diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)results reveal that the enhanced catalytic activity is attributed to the abundant Ce–H species,while the high selectivity results from low CO affinity.More importantly,a new reaction mechanism is proposed,which involves the reduction of bicarbonate to generate formate intermediate and CO by the H−released from Ce–H species.The new findings in this work will benefit the design of economic,efficient,and robust catalysts for low-temperature RWGS reactions.
