Sm_2 Fe_(17) prepared by reduction-diffusion method needs to be washed with water to remove calcium oxide. Electrochemical corrosion occurs when Sm_2 Fe_(17) powder is in contact with liquid water. Corrosion mechanism...Sm_2 Fe_(17) prepared by reduction-diffusion method needs to be washed with water to remove calcium oxide. Electrochemical corrosion occurs when Sm_2 Fe_(17) powder is in contact with liquid water. Corrosion mechanism of H_2 O on Sm_2 Fe_(17) powder and nitrogenation process of corroded Sm_2 Fe_(17) were studied by analyzing the structure and morphology. It is indicated that the metallic hydroxide forms and deposits on the Sm_2 Fe_(17) powder surfaces during water corrosion. At the same time, oxygen and hydrogen enter the unit cell of Sm2 Fe_(17), causing a slight increase in Curie temperature. In the subsequent nitriding process,the hydroxide is dehydrated and hydrogen is desorbed. The resulting oxide reacts with Sm_2 Fe_(17)N_x to form a-Fe and Sm_2 O_3. Thermodynamic calculations using the HSC Chemistry 6.0 software indicate that the reaction can occur spontaneously. The effect of water corrosion on the magnetic properties of the nitride can be eliminated by hydrogen reduction prior to nitriding.展开更多
Nitrogenation of SmFelolVIo2 powders was performed in a self-made furnace under a high-purity N2 atmo- sphere up to 40 MPa at 500 ℃. Upon nitrogenation at atmospheric pressure, the lattice parameters a and c increase...Nitrogenation of SmFelolVIo2 powders was performed in a self-made furnace under a high-purity N2 atmo- sphere up to 40 MPa at 500 ℃. Upon nitrogenation at atmospheric pressure, the lattice parameters a and c increase by 0.5% and 2.7%, respectively, whereas the Curie temperature Tc increases from 519 to 633 K. With further increasing the nitrogenation pressure to 20 and 40 MPa, the 1：12 main phase starts to decompose and a large amount of Mo and a-Fe precipitates. This leads to variation of Mo concentration in the 1：12 phase and causes a sharp decrease in Tc and in the coercivity. The relative complex permittivity and permeability of paraffin-SmFeloMO2 composites show multi-resonant behavior. After nitrogenation, the magnetic loss of the powders decreases, which may originate from the influence of eddy currents due to the increase in the particle size.展开更多
The reaction kinetics between nitrogen gas and Nd(Fe, Mo)_(12) intermetallic compound has been studied. The relationship between the reaction temperature, the reaction time with average mass fraction of N in samples h...The reaction kinetics between nitrogen gas and Nd(Fe, Mo)_(12) intermetallic compound has been studied. The relationship between the reaction temperature, the reaction time with average mass fraction of N in samples have been measured. The activation energy of first step reaction, E_f,(18.2 kJ/mol), is smaller than E_s (64.6 kJ /mol) of the second step during which nitrogen diffusion in the range 400～550℃ can be represented by an activated interstitial diffusion process. Heating above 550℃ leads to disproportion of the compound into NdN and α-Fe and the permanent properties will be damaged greatly.展开更多
An efficient KI catalyzed nitrogenation of aldehydes and alcohols for the direct synthesis of carbamoyl azides and ureas via a radical process has been developed. The simple operating procedures, the readily available...An efficient KI catalyzed nitrogenation of aldehydes and alcohols for the direct synthesis of carbamoyl azides and ureas via a radical process has been developed. The simple operating procedures, the readily available starting materials including aldehydes, alcohols and amines, as well as the utility of the products all make this strategy very attractive.展开更多
Amides are among the fundamental chemicals in organic chemistry.Compared to other carbonyl functional groups,the transformation of amide is relatively difficult and remains a challenge.The traditional deconstruction t...Amides are among the fundamental chemicals in organic chemistry.Compared to other carbonyl functional groups,the transformation of amide is relatively difficult and remains a challenge.The traditional deconstruction transformations of amides to other functional products are usually limited to twisted or electronically activated amides.Herein,we describe a direct nitrogenation approach to convert amides into nitriles.This chemistry provides a novel amide transformation pathway via both C–C and C–N bond cleavage.Interestingly,the simple,readily available,and inexpensive inorganic salt NaNO2 is successfully employed as a nitrogen source in this organic N-incorporation process.Applications of this study are demonstrated through the latestage modification of drug and natural product derivatives.展开更多
Chlorophyll-a is the most abundant chlorophyll pigment produced by marine phytoplankton,and it bears the isotope signature of the nitrate source assimilated in the N-atoms that are embedded in its porphyrin ring.The c...Chlorophyll-a is the most abundant chlorophyll pigment produced by marine phytoplankton,and it bears the isotope signature of the nitrate source assimilated in the N-atoms that are embedded in its porphyrin ring.The chloropigment and its degradation product,i.e.,pheophytin-a,could be well preserved in marine sediment,usually at nanomolar level.A sensitive and accurate measurement of theδ15N of chloropigment is capable of providing rich information to greatly enhance our understanding of past nitrogen cycling,which therefore is urgently needed.Hereby,we present a successful method based on two-step HPLC separation followed by'denitrifier method'.The N-content in acetone and potassium persulfate(K_(2)S_(2)O_(8))are very critical to the precision and accuracy of the measurements,because they constitute the majority of the N contamination to the Chl-a samples.In this method,the recrystallized K_(2)S_(2)O_(8)that is used as oxidization reagent was discovered to have aδ15N background of-15‰,consolidated by repeated examinations over a period of two months.This 15N background of K_(2)S_(2)O_(8)would cause-1‰–-2‰deviation on theδ^(15)N of sample that contains nanomolar level N,and highlight the need to examine theδ^(15)N of recrystallized K_(2)S_(2)O_(8)when it is used to oxidize samples of organic nitrogen.The overall measurement ofδ^(15)N pigment is reliable and has an average analytical precision better than±0.5‰(1σ).This study establish a sensitive method for accurate measurement of theδ^(15)N of nano-molar level chlorophyll pigment,and with no doubts will advance its wide application in marine nitrogen cycling studying.展开更多
Increasing atmospheric CO_(2)concentrations from~280 ppm in the pre-industrial era to over 420 ppm today, and projected to exceed 550 ppm by 2050(IPCC, 2023), are transforming the biochemical context of plant metaboli...Increasing atmospheric CO_(2)concentrations from~280 ppm in the pre-industrial era to over 420 ppm today, and projected to exceed 550 ppm by 2050(IPCC, 2023), are transforming the biochemical context of plant metabolism,causing restructuring of carbon and nitrogen balance in crops. Though elevated CO_(2)(eCO_(2)) increases photosynthetic efficacy and biomass accumulation in many C3crops, it also disrupts carbon-nitrogen balance, leading to nitrogen dilution in leaves and grains, eventually compromising food quality(Myers et al., 2014;Rezaei et al., 2023). Rice is a staple food that feeds nearly half of the world's population;it requires sustained yield gains, considering an estimated 35%-56%increase in demand by 2050, as the global population approaches 10 billion(Van Dijk et al., 2021), while reducing dependency on nitrogen fertilizers, whose production and overuse contribute significantly to greenhouse gas emission(Qian et al., 2023). Yet, most breeding programs remain regulated to present-day atmospheric conditions, overlooking the physiological and molecular adaptations required for future CO_(2)climates.展开更多
[Objectives]To investigate the effects of different planting densities and nitrogen application rates on the yield and quality of the tobacco cultivar Chuxue 80.[Methods]A field experiment was conducted in Hubei Provi...[Objectives]To investigate the effects of different planting densities and nitrogen application rates on the yield and quality of the tobacco cultivar Chuxue 80.[Methods]A field experiment was conducted in Hubei Province,evaluating various combinations of planting density and nitrogen rate for Chuxue 80.[Results]At the maturity stage,the TN1 treatment(5 kg N per 667 m^(2) with a density of 1900 plants per 667 m^(2))demonstrated the most favorable agronomic performance.The TN9 treatment(11 kg N per 667 m^(2) with a density of 1110 plants per 667 m^(2))achieved the highest wrapper tobacco yield and output value.Meanwhile,the TN5 treatment(8 kg N per 667 m^(2) with a density of 1515 plants per 667 m^(2))resulted in the best smoking quality.[Conclusions]The TN9 treatment,with a planting density of 1110 plants per 667 m^(2) and a nitrogen application rate of 11 kg per 667 m^(2),is recommended as the optimal cultivation practice for Chuxue 80 in Hubei Province.展开更多
A novel salt-tolerant aerobic denitrifying bacterium,Marinobacter sp.strain B108,was isolated from a marine recirculating aquaculture system(MRAS).The optimal aerobic denitrification parameters were CH_(3)COONa as car...A novel salt-tolerant aerobic denitrifying bacterium,Marinobacter sp.strain B108,was isolated from a marine recirculating aquaculture system(MRAS).The optimal aerobic denitrification parameters were CH_(3)COONa as carbon source,pH of 8,C/N of16,temperature of 35°C,dissolved oxygen(DO)of 6 mg/L and salinity of 30.Under these optimal conditions,Marinobacter sp.strain B108 had a removal efficiency of 100%for N O_(3)^(-)-N and 98.89%for total nitrogen(TN)within 24 h.The nitrate removal pathways of Marinobacter sp.strain B108 were included by the assimilative reduction pathway(N O_(3)^(-)-N→biomass N)and the dissimilatory reduction pathway(N O_(3)^(-)-N→N_(2))of aerobic denitrification,and lack of dissimilatory reduction to ammonium pathway(N O_(3)^(-)-N→N H_(4)^(+)-N).The nitrogen removal process of Marinobacter sp.strain B108 was mainly contributed by the dissimilatory reduction pathway.The kinetic parameters for N O_(3)^(-)-N and N O_(2)^(-)-N removal were determined as V_(m)of 971.566 and 165.336 mg/(gDCW·L·h),and K_(m)of 22.74 and 31.68 mg/L,respectively.This work reflects the practical application potential of Marinobacter sp.strain B108for nitrogen removal in MRAS.展开更多
Ecological floating bed is an important biological remediation method for water pollution control.During the removal of excess nutrients and pollutants,changes in environmental factors affect the characteristics of mi...Ecological floating bed is an important biological remediation method for water pollution control.During the removal of excess nutrients and pollutants,changes in environmental factors affect the characteristics of microorganisms in aquatic ecosystems.To understand the influences of ecological floating beds on size-fractionated microorganisms,we investigated the community assembly and nitrogen metabolic characteristics of three size-fractionated microorganism groups in the ecological floating bed area,using 18S rDNA,16S rDNA metabarcoding,and metagenomic sequencing techniques.Firstly,we discovered substantial differences between size-fractionated groups in the diversity and compositions of both microeukaryotic and bacterial communities,as well as the influences of floating beds on specific groups.The floating beds appeared to provide more habitats for heterotrophs and symbiotes while potentially inhibiting the growth of certain phytoplankton(cyanobacteria).Secondly,we observed that microeukaryotic and bacterial communities were predominantly influenced by stochastic and deterministic processes,respectively,and they both exhibited distinct patterns across different size-fractionated groups.Notably,microeukaryotic community assembly demonstrated a greater sensitivity to ecological floating beds,as indicated by an increase in dispersal limitation processes.Finally,the nitrogen metabolism functional genes revealed that microbes associated with large-sized particles played a crucial role in dissimilatory nitrate reduction to ammonium(DNRA)and denitrification processes within the floating bed area,thereby facilitating the removal of excess nitrogen nutrients from the water.In contrast,freeliving microorganisms from small-sized groups were linked mainly to the genes involved in nitrogen assimilation and assimilatory nitrate reduction to ammonium(ANRA)processes.These findings help understand the impact of ecological floating beds on the diversity and functional characteristics of microorganism communities in different size-fractionated groups.展开更多
Soybean is an important source of oil,protein,and feed.However,its yield is far below that of major cereal crops.The green revolution increased the yield of cereal crops partially through high-density planting of lodg...Soybean is an important source of oil,protein,and feed.However,its yield is far below that of major cereal crops.The green revolution increased the yield of cereal crops partially through high-density planting of lodging-resistant semi-dwarf varieties,but required more nitrogen fertilizers,posing an environmental threat.Genes that can improve nitrogen use efficiency need to be integrated into semi-dwarf varieties to avoid the overuse of fertilizers without the loss of dwarfism.Unlike cereal crops,soybean can assimilate atmospheric nitrogen through symbiotic bacteria.Here,we created new alleles of Gm GID1-2(Glycine max GIBBERELLIN INSENSITIVE DWARF 1-2)using clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated nuclease 9(Cas9)editing,which improved soybean architecture,yield,seed oil content,and nitrogen fixation,by regulation of important pathways and known genes related to branching,lipid metabolism,and nodule symbiosis.Gm GID1-2 knockout reduced plant height,and increased stem diameter and strength,number of branches,nodes on the primary stem,pods,and seeds per plant,leading to an increase in seed weight per plant and yield in soybean.The nodule number,nodule weight,nitrogenase activity,and nitrogen content were also improved in Gm GID1-2knockout soybean lines,which is novel compared with the semi-dwarf genes in cereal crops.No loss-of-function allele for Gm GID1-2 was identified in soybean germplasm and the edited Gm GID1-2s are superior to the natural alleles,suggesting the Gm GID1-2 knockout mutants generated in this study are valuable genetic resources to further improve soybean yield and seed oil content in future breeding programs.This study illustrates the pleiotropic functions of the GID1 knockout alleles with positive effects on plant architecture,yield,and nitrogen fixation in soybean,which provides a promising strategy toward sustainable agriculture.展开更多
Lodging is a major constraint limiting oil flax production efficiency in northern China.Crop lodging susceptibility is closely related to stem lignin content,and the regulatory mechanisms by which nitrogen and potassi...Lodging is a major constraint limiting oil flax production efficiency in northern China.Crop lodging susceptibility is closely related to stem lignin content,and the regulatory mechanisms by which nitrogen and potassium fertilization interactively influence lignin biosynthesis in oil flax stems require further investigation.Therefore,this study aimed to enhance lodging resistance and increase grain yield in oil flax.We examined the interactive effects of different nitrogen (75,150,and 225 kg N ha^(–1)) and potassium (60 and 90 kg K_(2)O ha^(–1)) fertilizer rates on lignin metabolism,lodging resistance,and grain yield during the 2022 and 2023 growing seasons.Results indicated that nitrogen and potassium fertilizer levels and their interactions promoted lignin accumulation,improved lodging resistance,and increased grain yield.Compared to the control (CK),the75–150 kg N ha^(–1) combined with 60 kg K_(2)O ha^(–1) treatments significantly enhanced the activities of key lignin-synthesizing enzymes (tyrosine ammonia-lyase (TAL),phenylalanine ammonia-lyase (PAL),cinnamyl alcohol dehydrogenase (CAD),and peroxidase (POD)) and upregulated the expression of 4CL1 and F5H3 genes,leading to a 29.63–43.30%increase in lignin content,improved stem bending strength and lodging resistance index,and a 23.27–32.34%increase in grain yield.Correlation analysis revealed that nitrogen and potassium fertilizers positively regulated enzyme activities and gene expression related to lignin biosynthesis,thereby facilitating lignin accumulation and enhancing stem mechanical strength and lodging resistance.Positive correlations were observed among lignin-related enzyme activities,gene expression,lodging resistance traits,and grain yield.In summary,the application of 75–150 kg N ha^(–1) in conjunction with 60 kg K_(2)O ha^(–1)promoted lignin biosynthesis and accumulation,enhanced lodging resistance,and increased grain yield in oil flax grown in the dryland farming region of central Gansu,China.Furthermore,this treatment provides a technical basis for cultivating stress-tolerant and high-yield oil flax in arid regions.展开更多
Nutrients play a crucial role in sustaining marine ecosystems and supporting mariculture,especially in seaweed aquaculture.Currently,seaweed farming,such as kelp cultivation,is entirely dependent on the natural supply...Nutrients play a crucial role in sustaining marine ecosystems and supporting mariculture,especially in seaweed aquaculture.Currently,seaweed farming,such as kelp cultivation,is entirely dependent on the natural supply of nutrients.Sanggou Bay in Shandong Peninsula,Yellow Sea,is renowned for its 60-year history of kelp cultivation;however,it is recently facing an increasing demand for nitrogen and phosphorus due to the expansion in aquaculture scale and production.There is no doubt that nutrient addition can enhance and sustain the production,but it is crucial to understand its effect on kelp growth under current nutrients condition and the potential ecological risks.Our in-field nutrient enrichment experiments show that nitrogen and phosphorus additions promoted the kelp biomass during the early growth stages,and have no adverse effects on phytoplankton or seawater nutrient levels throughout the experiment.From a long-term perspective,increasing nutrient supply appears to be an essential strategy for sustaining the aquaculture of kelp.展开更多
As the global leader in rice production,China's paddy fields contribute substantially to greenhouse gas emissions through methane(CH_(4))and nitrous oxide(N_(2)O)releases.Aromatic rice cultivation practices have b...As the global leader in rice production,China's paddy fields contribute substantially to greenhouse gas emissions through methane(CH_(4))and nitrous oxide(N_(2)O)releases.Aromatic rice cultivation practices have been optimized to enhance the aroma,so the relationship between its cultivation and greenhouse gas emissions from paddy fields is unclear.To investigate how aroma-enhancing cultivation practices drive microbial community dynamics in aromatic rice paddies and their implications for greenhouse gas emissions,a two-year experiment in five ecological locations(Xingning,Nanxiong,Conghua,Luoding,and Zengcheng)compared two farming practices:partial organic substitution for inorganic fertilizers combined with water-saving irrigation(IOF+W)and traditional cultivation(CK).The CH_(4)and N_(2)O emissions,soil microbial composition and function,global warming potential(GWP),nitrogen use efficiency,yield,and the content of 2-acetyl-1-pyrroline(2-AP)were measured and analyzed.The main purpose was to investigate the impact of IOF+W on CH_(4)and N_(2)O emissions and their relationship with soil microorganisms.The results showed that IOF+W significantly reduced CH_(4)emission fluxes and totals(36.95%)and GWP(31.29%),while significantly increasing N_(2)O emission fluxes and totals(14.82%).The soil microbial community structure was reshaped by the IOF+W treatment,which suppressed methanogens but enhanced the abundances of nitrifying and denitrifying bacteria.Key enzymatic activities involved in CH_(4)production,such as methyl-coenzyme M reductase,formylmethanofuran dehydrogenase,and methyltransferase,decreased.In contrast,the activity of the key CH_(4)-oxidizing enzyme methanol dehydrogenase increased.This shift led to an overall attenuation of the CH_(4)production metabolism while enhancing the CH_(4)oxidation metabolism.In addition,the activities of pivotal enzymes involved in denitrification and nitrification were improved,thus enhancing nitrogen nitrification and denitrification metabolism.Moreover,the IOF+W treatment significantly increased nitrogen use efficiency(47.83%),yield(14.77%),and 2-AP content(13.78%).Therefore,the IOF+W treatment demonstrated good efficacy as a sustainable strategy for achieving productive,green,resource-efficient,and premium-quality aromatic rice cultivation in South China.展开更多
Green ammonia,produced by harnessing renewable solar energy to split nitrogen,plays a pivotal role in both agricultural practices and forthcoming energy configurations,driving the sustainable development of human soci...Green ammonia,produced by harnessing renewable solar energy to split nitrogen,plays a pivotal role in both agricultural practices and forthcoming energy configurations,driving the sustainable development of human society with zero-carbon emissions.However,nitrogen photoreduction currently faces the challenges of poor activation ability and low yield,and it is still challenging to unravel the intertwined problems in this field and provide direction for its development due to the complex reaction mechanism and multidisciplinary aspects such as photochemistry,catalysis,interface science,and technology.This review focuses on capturing the latest advances in photocatalytic nitrogen-to-ammonia conversion,delving into fundamental principles regarding the process,efficient photocatalysts for practical ammonia synthesis,and well-designed catalytic environments.Besides,this article provides insightful guidelines for analyzing complicated reaction mechanisms and identifying key bottlenecks or specific rate-determining steps,such as reactant activation,interfacial reaction engineering,and hydrogen evolution side reactions.By integrating perspectives from atomic mechanisms,nanoscale photocatalysts,microscale interfacial engineering,and macroscale reaction system design,this review advances the development of nitrogen photoreduction from proof-of-concept discoveries to viable solar-to-chemical conversion technologies,while also providing a valuable entry point for researchers into this burgeoning field.展开更多
MXene derivatives are notable two-dimensional nanomaterials with numerous prospective applications in the domains of energy development.MXene derivative,MBene,diversifies its focus on energy storage and harvesting due...MXene derivatives are notable two-dimensional nanomaterials with numerous prospective applications in the domains of energy development.MXene derivative,MBene,diversifies its focus on energy storage and harvesting due to its exceptional electrical conductivity,structural flexibility,and mechanical properties.This comprehensive review describes the sandwich-like structure of the synthesized MBene,derived from its multilayered parent material and its distinct chemical framework to date.The fields of focus encompass the investigation of novel MBenes,the study of phase-changing mechanisms,and the examination of hex-MBenes,ortho-MBenes,tetra-MBenes,tri-MBenes,and MXenes with identical transition metal components.A critical analysis is also provided on the electrochemical mechanism and performance of MBene in energy storage(Li/Na/Mg/Ca/Li–S batteries and supercapacitors),as well as conversion and harvesting(CO_(2) reduction,and nitrogen reduction reactions).The persistent difficulties associated with conducting experimental synthesis and establishing artificial intelligence-based forecasts are extensively deliberated alongside the potential and forthcoming prospects of MBenes.This review provides a single platform for an overview of the MBene’s potential in energy storage and harvesting.展开更多
The premature decay of electrochemical nitrogen reduction reaction(eNRR)performance at low electrode potentials remains a major obstacle to practical applications,which is primarily attributed to the competition from ...The premature decay of electrochemical nitrogen reduction reaction(eNRR)performance at low electrode potentials remains a major obstacle to practical applications,which is primarily attributed to the competition from the hydrogen evolution reaction(HER).A new paradigm capable of transcending current selectivity constraints is urgently required to advance eNRR toward industrial implementation.In this work,we propose two practical selectivity descriptors(ΔΔG andΔU)based on a systematic investigation of the potential-dependent competition between eNRR and HER on confined dual-atom catalysts.The descriptorΔΔG(G_(N_(2))-ΔG_(H))identifies the potential range where N_(2)adsorption dominates over H adsorption,whileΔU(U_(cross)-U_(eNRR))specifies the potential range to trigger direct eNRR,offering a quantitative benchmark for rational catalyst design.Ideal catalysts should maintain N_(2)-preferential adsorption across a broad potential window to facilitate direct eNRR.Guided by this insight,we demonstrate that confined dual-atom configurations with optimized interatomic distances can simultaneously achieve both overwhelming N_(2)adsorption and sufficient activation,thereby overcoming the conventional selectivity limitations.This strategy enables ammonia synthesis with industrially relevant production rates and current density even at elevated potentials.Our mechanistic insights not only elucidate the root causes of performance limitations in eNRR but also offer a rational design framework for developing high-performance catalysts across a broad range of electrochemical transformations.展开更多
Soil organic carbon in forest affects nutrient availability,microbial processes,and organic matter inputs.Dominant tree species have increasingly shifted from ectomycorrhizal to arbuscular mycorrhizal associations in ...Soil organic carbon in forest affects nutrient availability,microbial processes,and organic matter inputs.Dominant tree species have increasingly shifted from ectomycorrhizal to arbuscular mycorrhizal associations in subtropical forests.However,the consequences of this shift for soil organic carbon is poorly understood.To address this,a field study was conducted across a natural gradient of arbuscular tree associations to investigate how different mycorrhizal associations affect soil organic carbon quantity,composition,chemical stability,and related soil properties.Soil organic carbon fractions,functional groups,microbial enzyme activities were analyzed.Results showed that increasing arbuscular mycorrhizal dominance was associated with declines in total soil organic carbon,particularly in recalcitrant and aromatic carbon forms.Ectomycorrhizaldominated forests exhibited higher nitrogen availability and elevated nitrogen-hydrolyzing enzyme activity,suggesting enhanced nitrogen acquisition strategies that suppress soil organic carbon decomposition and promote carbon retention.These findings indicate that mycorrhizal-mediated shifts in tree composition may significantly alter soil carbon sequestration potential.Incorporating mycorrhizal functional traits into forest management and carbon modeling could improve predictions of soil organic carbon responses under future environmental change.展开更多
The catalytic transferred of small molecules into high-value chemical products in green methods are highly perused,and has obtained huge attention.In this field,great progress has been achieved during the past five ye...The catalytic transferred of small molecules into high-value chemical products in green methods are highly perused,and has obtained huge attention.In this field,great progress has been achieved during the past five years.Followed by the roadmap(Chinese Chemical Letters,2019,30,2089-2109)written by us before five years,we think that it should be updated to give more insights in this field.Thus,we write the present roadmap based on the fast changed background.In this roadmap,oxygen and carbon dioxide reduction reactions(including at high temperature),photocatalytic hydrogen generation and carbon dioxide reduction reactions,(photo)electrocatalytic reduction of O_(2)to H_(2)O_(2)and NH_(3)generated from N_(2) are discussed.The progress and challenges in above catalytic processes are given.We believe this manuscript will give the researchers more suggestions and help them to obtain useful information in this field.展开更多
基金Project supported by Natural Science Foundation of Ningbo,China(2017A610079)Technology Innovation&Achievement Industrialization Project of Ningbo China(2014B11010)
文摘Sm_2 Fe_(17) prepared by reduction-diffusion method needs to be washed with water to remove calcium oxide. Electrochemical corrosion occurs when Sm_2 Fe_(17) powder is in contact with liquid water. Corrosion mechanism of H_2 O on Sm_2 Fe_(17) powder and nitrogenation process of corroded Sm_2 Fe_(17) were studied by analyzing the structure and morphology. It is indicated that the metallic hydroxide forms and deposits on the Sm_2 Fe_(17) powder surfaces during water corrosion. At the same time, oxygen and hydrogen enter the unit cell of Sm2 Fe_(17), causing a slight increase in Curie temperature. In the subsequent nitriding process,the hydroxide is dehydrated and hydrogen is desorbed. The resulting oxide reacts with Sm_2 Fe_(17)N_x to form a-Fe and Sm_2 O_3. Thermodynamic calculations using the HSC Chemistry 6.0 software indicate that the reaction can occur spontaneously. The effect of water corrosion on the magnetic properties of the nitride can be eliminated by hydrogen reduction prior to nitriding.
基金financially supported by the National Natural Science Foundation of China (No. 51261001)Liaoning Provincial Natural Science Foundation (No. 2013020105)Shenyang Science and Technology Foundation (No. F13-316-139)
文摘Nitrogenation of SmFelolVIo2 powders was performed in a self-made furnace under a high-purity N2 atmo- sphere up to 40 MPa at 500 ℃. Upon nitrogenation at atmospheric pressure, the lattice parameters a and c increase by 0.5% and 2.7%, respectively, whereas the Curie temperature Tc increases from 519 to 633 K. With further increasing the nitrogenation pressure to 20 and 40 MPa, the 1：12 main phase starts to decompose and a large amount of Mo and a-Fe precipitates. This leads to variation of Mo concentration in the 1：12 phase and causes a sharp decrease in Tc and in the coercivity. The relative complex permittivity and permeability of paraffin-SmFeloMO2 composites show multi-resonant behavior. After nitrogenation, the magnetic loss of the powders decreases, which may originate from the influence of eddy currents due to the increase in the particle size.
文摘The reaction kinetics between nitrogen gas and Nd(Fe, Mo)_(12) intermetallic compound has been studied. The relationship between the reaction temperature, the reaction time with average mass fraction of N in samples have been measured. The activation energy of first step reaction, E_f,(18.2 kJ/mol), is smaller than E_s (64.6 kJ /mol) of the second step during which nitrogen diffusion in the range 400～550℃ can be represented by an activated interstitial diffusion process. Heating above 550℃ leads to disproportion of the compound into NdN and α-Fe and the permanent properties will be damaged greatly.
基金Financial support from National Basic Research Program of China （973 Program） （No. 2015CB856600）, the National Natural Science Foundation of China （Nos. 21325206, 21632001）, National Young Top-notch Talent Support Program, CAS Interdisciplinary Innovation Team, and Peking University Health Science Center （Nos. BMU20150505, BMU20160541） is greatly ap- preciated. We thank Bencong Zhu and Ao Sun in this group for reproducing the results of 2a and 2k.
文摘An efficient KI catalyzed nitrogenation of aldehydes and alcohols for the direct synthesis of carbamoyl azides and ureas via a radical process has been developed. The simple operating procedures, the readily available starting materials including aldehydes, alcohols and amines, as well as the utility of the products all make this strategy very attractive.
基金the National Key R&D Program of China(grant no.2021YFA1501700)the NSFC(grant nos.22131002,22161142019,81821004),and the Tencent Foundation for financial support.
文摘Amides are among the fundamental chemicals in organic chemistry.Compared to other carbonyl functional groups,the transformation of amide is relatively difficult and remains a challenge.The traditional deconstruction transformations of amides to other functional products are usually limited to twisted or electronically activated amides.Herein,we describe a direct nitrogenation approach to convert amides into nitriles.This chemistry provides a novel amide transformation pathway via both C–C and C–N bond cleavage.Interestingly,the simple,readily available,and inexpensive inorganic salt NaNO2 is successfully employed as a nitrogen source in this organic N-incorporation process.Applications of this study are demonstrated through the latestage modification of drug and natural product derivatives.
基金National Science Foundation of China(No.41576082)。
文摘Chlorophyll-a is the most abundant chlorophyll pigment produced by marine phytoplankton,and it bears the isotope signature of the nitrate source assimilated in the N-atoms that are embedded in its porphyrin ring.The chloropigment and its degradation product,i.e.,pheophytin-a,could be well preserved in marine sediment,usually at nanomolar level.A sensitive and accurate measurement of theδ15N of chloropigment is capable of providing rich information to greatly enhance our understanding of past nitrogen cycling,which therefore is urgently needed.Hereby,we present a successful method based on two-step HPLC separation followed by'denitrifier method'.The N-content in acetone and potassium persulfate(K_(2)S_(2)O_(8))are very critical to the precision and accuracy of the measurements,because they constitute the majority of the N contamination to the Chl-a samples.In this method,the recrystallized K_(2)S_(2)O_(8)that is used as oxidization reagent was discovered to have aδ15N background of-15‰,consolidated by repeated examinations over a period of two months.This 15N background of K_(2)S_(2)O_(8)would cause-1‰–-2‰deviation on theδ^(15)N of sample that contains nanomolar level N,and highlight the need to examine theδ^(15)N of recrystallized K_(2)S_(2)O_(8)when it is used to oxidize samples of organic nitrogen.The overall measurement ofδ^(15)N pigment is reliable and has an average analytical precision better than±0.5‰(1σ).This study establish a sensitive method for accurate measurement of theδ^(15)N of nano-molar level chlorophyll pigment,and with no doubts will advance its wide application in marine nitrogen cycling studying.
基金supported by the Guangdong-Hong Kong Joint Laboratory for Carbon Neutrality(No.2023B1212120003)the Guangdong Talent Program(No.2023JC10N060)+1 种基金the Guangdong Science and Technology Program(No.2022B1212040001)the Special Fund for Science and Technology Innovation Strategy of Guangdong Province(Grant No.2022660500250009604)。
文摘Increasing atmospheric CO_(2)concentrations from~280 ppm in the pre-industrial era to over 420 ppm today, and projected to exceed 550 ppm by 2050(IPCC, 2023), are transforming the biochemical context of plant metabolism,causing restructuring of carbon and nitrogen balance in crops. Though elevated CO_(2)(eCO_(2)) increases photosynthetic efficacy and biomass accumulation in many C3crops, it also disrupts carbon-nitrogen balance, leading to nitrogen dilution in leaves and grains, eventually compromising food quality(Myers et al., 2014;Rezaei et al., 2023). Rice is a staple food that feeds nearly half of the world's population;it requires sustained yield gains, considering an estimated 35%-56%increase in demand by 2050, as the global population approaches 10 billion(Van Dijk et al., 2021), while reducing dependency on nitrogen fertilizers, whose production and overuse contribute significantly to greenhouse gas emission(Qian et al., 2023). Yet, most breeding programs remain regulated to present-day atmospheric conditions, overlooking the physiological and molecular adaptations required for future CO_(2)climates.
基金Supported by Science and Technology Project of China Tobacco Zhejiang Industrial Co.,Ltd.(2023330000340093).
文摘[Objectives]To investigate the effects of different planting densities and nitrogen application rates on the yield and quality of the tobacco cultivar Chuxue 80.[Methods]A field experiment was conducted in Hubei Province,evaluating various combinations of planting density and nitrogen rate for Chuxue 80.[Results]At the maturity stage,the TN1 treatment(5 kg N per 667 m^(2) with a density of 1900 plants per 667 m^(2))demonstrated the most favorable agronomic performance.The TN9 treatment(11 kg N per 667 m^(2) with a density of 1110 plants per 667 m^(2))achieved the highest wrapper tobacco yield and output value.Meanwhile,the TN5 treatment(8 kg N per 667 m^(2) with a density of 1515 plants per 667 m^(2))resulted in the best smoking quality.[Conclusions]The TN9 treatment,with a planting density of 1110 plants per 667 m^(2) and a nitrogen application rate of 11 kg per 667 m^(2),is recommended as the optimal cultivation practice for Chuxue 80 in Hubei Province.
基金National Natural Science Foundation of China(No.51978636)。
文摘A novel salt-tolerant aerobic denitrifying bacterium,Marinobacter sp.strain B108,was isolated from a marine recirculating aquaculture system(MRAS).The optimal aerobic denitrification parameters were CH_(3)COONa as carbon source,pH of 8,C/N of16,temperature of 35°C,dissolved oxygen(DO)of 6 mg/L and salinity of 30.Under these optimal conditions,Marinobacter sp.strain B108 had a removal efficiency of 100%for N O_(3)^(-)-N and 98.89%for total nitrogen(TN)within 24 h.The nitrate removal pathways of Marinobacter sp.strain B108 were included by the assimilative reduction pathway(N O_(3)^(-)-N→biomass N)and the dissimilatory reduction pathway(N O_(3)^(-)-N→N_(2))of aerobic denitrification,and lack of dissimilatory reduction to ammonium pathway(N O_(3)^(-)-N→N H_(4)^(+)-N).The nitrogen removal process of Marinobacter sp.strain B108 was mainly contributed by the dissimilatory reduction pathway.The kinetic parameters for N O_(3)^(-)-N and N O_(2)^(-)-N removal were determined as V_(m)of 971.566 and 165.336 mg/(gDCW·L·h),and K_(m)of 22.74 and 31.68 mg/L,respectively.This work reflects the practical application potential of Marinobacter sp.strain B108for nitrogen removal in MRAS.
基金Supported by the National Natural Science Foundation of China(Nos.42141003,42176147)the National Key Research and Development Program of China(No.2022YFF0802204)the Xiamen Key Laboratory of Urban Sea Ecological Conservation and Restoration(USER)(Nos.USER2021-1,USER2021-5)。
文摘Ecological floating bed is an important biological remediation method for water pollution control.During the removal of excess nutrients and pollutants,changes in environmental factors affect the characteristics of microorganisms in aquatic ecosystems.To understand the influences of ecological floating beds on size-fractionated microorganisms,we investigated the community assembly and nitrogen metabolic characteristics of three size-fractionated microorganism groups in the ecological floating bed area,using 18S rDNA,16S rDNA metabarcoding,and metagenomic sequencing techniques.Firstly,we discovered substantial differences between size-fractionated groups in the diversity and compositions of both microeukaryotic and bacterial communities,as well as the influences of floating beds on specific groups.The floating beds appeared to provide more habitats for heterotrophs and symbiotes while potentially inhibiting the growth of certain phytoplankton(cyanobacteria).Secondly,we observed that microeukaryotic and bacterial communities were predominantly influenced by stochastic and deterministic processes,respectively,and they both exhibited distinct patterns across different size-fractionated groups.Notably,microeukaryotic community assembly demonstrated a greater sensitivity to ecological floating beds,as indicated by an increase in dispersal limitation processes.Finally,the nitrogen metabolism functional genes revealed that microbes associated with large-sized particles played a crucial role in dissimilatory nitrate reduction to ammonium(DNRA)and denitrification processes within the floating bed area,thereby facilitating the removal of excess nitrogen nutrients from the water.In contrast,freeliving microorganisms from small-sized groups were linked mainly to the genes involved in nitrogen assimilation and assimilatory nitrate reduction to ammonium(ANRA)processes.These findings help understand the impact of ecological floating beds on the diversity and functional characteristics of microorganism communities in different size-fractionated groups.
基金supported by the National Natural Science Foundation of China(32372192)the Core Technology Development for Breeding Program of Jiangsu Province(JBGS-2021-014)Jiangsu Key Laboratory of Soybean Biotechnology and Intelligent Breeding(BM2024005)。
文摘Soybean is an important source of oil,protein,and feed.However,its yield is far below that of major cereal crops.The green revolution increased the yield of cereal crops partially through high-density planting of lodging-resistant semi-dwarf varieties,but required more nitrogen fertilizers,posing an environmental threat.Genes that can improve nitrogen use efficiency need to be integrated into semi-dwarf varieties to avoid the overuse of fertilizers without the loss of dwarfism.Unlike cereal crops,soybean can assimilate atmospheric nitrogen through symbiotic bacteria.Here,we created new alleles of Gm GID1-2(Glycine max GIBBERELLIN INSENSITIVE DWARF 1-2)using clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated nuclease 9(Cas9)editing,which improved soybean architecture,yield,seed oil content,and nitrogen fixation,by regulation of important pathways and known genes related to branching,lipid metabolism,and nodule symbiosis.Gm GID1-2 knockout reduced plant height,and increased stem diameter and strength,number of branches,nodes on the primary stem,pods,and seeds per plant,leading to an increase in seed weight per plant and yield in soybean.The nodule number,nodule weight,nitrogenase activity,and nitrogen content were also improved in Gm GID1-2knockout soybean lines,which is novel compared with the semi-dwarf genes in cereal crops.No loss-of-function allele for Gm GID1-2 was identified in soybean germplasm and the edited Gm GID1-2s are superior to the natural alleles,suggesting the Gm GID1-2 knockout mutants generated in this study are valuable genetic resources to further improve soybean yield and seed oil content in future breeding programs.This study illustrates the pleiotropic functions of the GID1 knockout alleles with positive effects on plant architecture,yield,and nitrogen fixation in soybean,which provides a promising strategy toward sustainable agriculture.
基金funded by the National Natural Science Foundation of China (31760363)the Earmarked Fund for CARS (CARS-14-1-16)+1 种基金the Gansu Education Science and Technology Innovation Industry Support Program,China (2021CYZC-38)the Gansu Provincial Key Laboratory of Arid Land Crop Science,Gansu Agricultural University,China (GSCS-2020-Z6)。
文摘Lodging is a major constraint limiting oil flax production efficiency in northern China.Crop lodging susceptibility is closely related to stem lignin content,and the regulatory mechanisms by which nitrogen and potassium fertilization interactively influence lignin biosynthesis in oil flax stems require further investigation.Therefore,this study aimed to enhance lodging resistance and increase grain yield in oil flax.We examined the interactive effects of different nitrogen (75,150,and 225 kg N ha^(–1)) and potassium (60 and 90 kg K_(2)O ha^(–1)) fertilizer rates on lignin metabolism,lodging resistance,and grain yield during the 2022 and 2023 growing seasons.Results indicated that nitrogen and potassium fertilizer levels and their interactions promoted lignin accumulation,improved lodging resistance,and increased grain yield.Compared to the control (CK),the75–150 kg N ha^(–1) combined with 60 kg K_(2)O ha^(–1) treatments significantly enhanced the activities of key lignin-synthesizing enzymes (tyrosine ammonia-lyase (TAL),phenylalanine ammonia-lyase (PAL),cinnamyl alcohol dehydrogenase (CAD),and peroxidase (POD)) and upregulated the expression of 4CL1 and F5H3 genes,leading to a 29.63–43.30%increase in lignin content,improved stem bending strength and lodging resistance index,and a 23.27–32.34%increase in grain yield.Correlation analysis revealed that nitrogen and potassium fertilizers positively regulated enzyme activities and gene expression related to lignin biosynthesis,thereby facilitating lignin accumulation and enhancing stem mechanical strength and lodging resistance.Positive correlations were observed among lignin-related enzyme activities,gene expression,lodging resistance traits,and grain yield.In summary,the application of 75–150 kg N ha^(–1) in conjunction with 60 kg K_(2)O ha^(–1)promoted lignin biosynthesis and accumulation,enhanced lodging resistance,and increased grain yield in oil flax grown in the dryland farming region of central Gansu,China.Furthermore,this treatment provides a technical basis for cultivating stress-tolerant and high-yield oil flax in arid regions.
基金Supported by the Laoshan Laboratory(No.LSKJ202204005)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA23050502)+2 种基金the State Key Program of National Natural Science Foundation of China(No.42130411)the International Science Partnership Program of the Chinese Academy of Sciences(Nos.121311KYSB20190029,133137KYSB20200002)the Key Deployment Project of Centre for Ocean Mega-Research of Science,Chinese Academy of Sciences(CAS)(No.COMS2019J03)。
文摘Nutrients play a crucial role in sustaining marine ecosystems and supporting mariculture,especially in seaweed aquaculture.Currently,seaweed farming,such as kelp cultivation,is entirely dependent on the natural supply of nutrients.Sanggou Bay in Shandong Peninsula,Yellow Sea,is renowned for its 60-year history of kelp cultivation;however,it is recently facing an increasing demand for nitrogen and phosphorus due to the expansion in aquaculture scale and production.There is no doubt that nutrient addition can enhance and sustain the production,but it is crucial to understand its effect on kelp growth under current nutrients condition and the potential ecological risks.Our in-field nutrient enrichment experiments show that nitrogen and phosphorus additions promoted the kelp biomass during the early growth stages,and have no adverse effects on phytoplankton or seawater nutrient levels throughout the experiment.From a long-term perspective,increasing nutrient supply appears to be an essential strategy for sustaining the aquaculture of kelp.
基金provided by the Guangdong Province Low-Carbon Fragrant Rice Cultivation Demonstration Project,China(F23032)。
文摘As the global leader in rice production,China's paddy fields contribute substantially to greenhouse gas emissions through methane(CH_(4))and nitrous oxide(N_(2)O)releases.Aromatic rice cultivation practices have been optimized to enhance the aroma,so the relationship between its cultivation and greenhouse gas emissions from paddy fields is unclear.To investigate how aroma-enhancing cultivation practices drive microbial community dynamics in aromatic rice paddies and their implications for greenhouse gas emissions,a two-year experiment in five ecological locations(Xingning,Nanxiong,Conghua,Luoding,and Zengcheng)compared two farming practices:partial organic substitution for inorganic fertilizers combined with water-saving irrigation(IOF+W)and traditional cultivation(CK).The CH_(4)and N_(2)O emissions,soil microbial composition and function,global warming potential(GWP),nitrogen use efficiency,yield,and the content of 2-acetyl-1-pyrroline(2-AP)were measured and analyzed.The main purpose was to investigate the impact of IOF+W on CH_(4)and N_(2)O emissions and their relationship with soil microorganisms.The results showed that IOF+W significantly reduced CH_(4)emission fluxes and totals(36.95%)and GWP(31.29%),while significantly increasing N_(2)O emission fluxes and totals(14.82%).The soil microbial community structure was reshaped by the IOF+W treatment,which suppressed methanogens but enhanced the abundances of nitrifying and denitrifying bacteria.Key enzymatic activities involved in CH_(4)production,such as methyl-coenzyme M reductase,formylmethanofuran dehydrogenase,and methyltransferase,decreased.In contrast,the activity of the key CH_(4)-oxidizing enzyme methanol dehydrogenase increased.This shift led to an overall attenuation of the CH_(4)production metabolism while enhancing the CH_(4)oxidation metabolism.In addition,the activities of pivotal enzymes involved in denitrification and nitrification were improved,thus enhancing nitrogen nitrification and denitrification metabolism.Moreover,the IOF+W treatment significantly increased nitrogen use efficiency(47.83%),yield(14.77%),and 2-AP content(13.78%).Therefore,the IOF+W treatment demonstrated good efficacy as a sustainable strategy for achieving productive,green,resource-efficient,and premium-quality aromatic rice cultivation in South China.
基金financially supported by the National Energy Green Hydrogen Refining Research&Development Center,National Natural Science Foundation of China(No.22476222)Natural Science Funds of Guangdong for Distinguished Young Scholar(No.2022B1515020098).
文摘Green ammonia,produced by harnessing renewable solar energy to split nitrogen,plays a pivotal role in both agricultural practices and forthcoming energy configurations,driving the sustainable development of human society with zero-carbon emissions.However,nitrogen photoreduction currently faces the challenges of poor activation ability and low yield,and it is still challenging to unravel the intertwined problems in this field and provide direction for its development due to the complex reaction mechanism and multidisciplinary aspects such as photochemistry,catalysis,interface science,and technology.This review focuses on capturing the latest advances in photocatalytic nitrogen-to-ammonia conversion,delving into fundamental principles regarding the process,efficient photocatalysts for practical ammonia synthesis,and well-designed catalytic environments.Besides,this article provides insightful guidelines for analyzing complicated reaction mechanisms and identifying key bottlenecks or specific rate-determining steps,such as reactant activation,interfacial reaction engineering,and hydrogen evolution side reactions.By integrating perspectives from atomic mechanisms,nanoscale photocatalysts,microscale interfacial engineering,and macroscale reaction system design,this review advances the development of nitrogen photoreduction from proof-of-concept discoveries to viable solar-to-chemical conversion technologies,while also providing a valuable entry point for researchers into this burgeoning field.
基金supported by the National Natural Science Foundation of China(No.52302241 and 22225801)the Major Science and Technology Programs of Henan Province(241100240200)the China Postdoctoral Science Foundation(No.2023M730940).
文摘MXene derivatives are notable two-dimensional nanomaterials with numerous prospective applications in the domains of energy development.MXene derivative,MBene,diversifies its focus on energy storage and harvesting due to its exceptional electrical conductivity,structural flexibility,and mechanical properties.This comprehensive review describes the sandwich-like structure of the synthesized MBene,derived from its multilayered parent material and its distinct chemical framework to date.The fields of focus encompass the investigation of novel MBenes,the study of phase-changing mechanisms,and the examination of hex-MBenes,ortho-MBenes,tetra-MBenes,tri-MBenes,and MXenes with identical transition metal components.A critical analysis is also provided on the electrochemical mechanism and performance of MBene in energy storage(Li/Na/Mg/Ca/Li–S batteries and supercapacitors),as well as conversion and harvesting(CO_(2) reduction,and nitrogen reduction reactions).The persistent difficulties associated with conducting experimental synthesis and establishing artificial intelligence-based forecasts are extensively deliberated alongside the potential and forthcoming prospects of MBenes.This review provides a single platform for an overview of the MBene’s potential in energy storage and harvesting.
基金supported by the Taishan Scholar Program of Shandong Province(tsqn202507090)Postdoctoral Fellowship Program of China Postdoctoral Science Foundation(CPSF)(GZB20250022)+1 种基金Natural Science Foundation of Shandong Province(ZR2025QC1086)Young Talents Project at Ocean University of China。
文摘The premature decay of electrochemical nitrogen reduction reaction(eNRR)performance at low electrode potentials remains a major obstacle to practical applications,which is primarily attributed to the competition from the hydrogen evolution reaction(HER).A new paradigm capable of transcending current selectivity constraints is urgently required to advance eNRR toward industrial implementation.In this work,we propose two practical selectivity descriptors(ΔΔG andΔU)based on a systematic investigation of the potential-dependent competition between eNRR and HER on confined dual-atom catalysts.The descriptorΔΔG(G_(N_(2))-ΔG_(H))identifies the potential range where N_(2)adsorption dominates over H adsorption,whileΔU(U_(cross)-U_(eNRR))specifies the potential range to trigger direct eNRR,offering a quantitative benchmark for rational catalyst design.Ideal catalysts should maintain N_(2)-preferential adsorption across a broad potential window to facilitate direct eNRR.Guided by this insight,we demonstrate that confined dual-atom configurations with optimized interatomic distances can simultaneously achieve both overwhelming N_(2)adsorption and sufficient activation,thereby overcoming the conventional selectivity limitations.This strategy enables ammonia synthesis with industrially relevant production rates and current density even at elevated potentials.Our mechanistic insights not only elucidate the root causes of performance limitations in eNRR but also offer a rational design framework for developing high-performance catalysts across a broad range of electrochemical transformations.
基金supported by the National Natural Science Foundation of China(grant numbers 32471851,32171759 and 32201533)Double Thousand Plan of Jiangxi Province(jxsq2023201058)Jiangxi Province Ganpo Juncai Support Plan(2024BCE50043).
文摘Soil organic carbon in forest affects nutrient availability,microbial processes,and organic matter inputs.Dominant tree species have increasingly shifted from ectomycorrhizal to arbuscular mycorrhizal associations in subtropical forests.However,the consequences of this shift for soil organic carbon is poorly understood.To address this,a field study was conducted across a natural gradient of arbuscular tree associations to investigate how different mycorrhizal associations affect soil organic carbon quantity,composition,chemical stability,and related soil properties.Soil organic carbon fractions,functional groups,microbial enzyme activities were analyzed.Results showed that increasing arbuscular mycorrhizal dominance was associated with declines in total soil organic carbon,particularly in recalcitrant and aromatic carbon forms.Ectomycorrhizaldominated forests exhibited higher nitrogen availability and elevated nitrogen-hydrolyzing enzyme activity,suggesting enhanced nitrogen acquisition strategies that suppress soil organic carbon decomposition and promote carbon retention.These findings indicate that mycorrhizal-mediated shifts in tree composition may significantly alter soil carbon sequestration potential.Incorporating mycorrhizal functional traits into forest management and carbon modeling could improve predictions of soil organic carbon responses under future environmental change.
基金supported by the National Natural Science Foundation of China(Nos.22268003,22102095,52204320,U20A20246 and 12275199,U22A20418,22075196,21972110,52202208)National Key Research and Development Program of China(Nos.2023YFA1507903,2022YFB3803600,2022YFB4002501)+9 种基金SINOPEC(Beijing)Research Institute of Chemical Industry Co.,Ltd.(No.223239)the Fundamental Research Funds for the Central Universities(No.CCNU22JC017)the Postdoctoral Science Foundation of China(No.2021M692535)the Natural Science Foundation of Shaanxi Province(No.2022JQ-095)the Basic Research Project Foundation of Xi’an Jiaotong University(No.xzy012024012)the Youth Foundation of State Key Laboratory of Electrical Insulation and Power Equipment(No.EIPE2131)the Russian Science Foundation(No.22-13-00035)the Ministry of Science and Higher Education within the framework of a State Assignment of the Ioffe Institute,Russian Academy of Sciences(No.FFUG-2024-0036)Yunnan Fundamental Research Projects(No.202305AF150116)the Research Project Supported by Shanxi Scholarship Council of China(No.2022-050)。
文摘The catalytic transferred of small molecules into high-value chemical products in green methods are highly perused,and has obtained huge attention.In this field,great progress has been achieved during the past five years.Followed by the roadmap(Chinese Chemical Letters,2019,30,2089-2109)written by us before five years,we think that it should be updated to give more insights in this field.Thus,we write the present roadmap based on the fast changed background.In this roadmap,oxygen and carbon dioxide reduction reactions(including at high temperature),photocatalytic hydrogen generation and carbon dioxide reduction reactions,(photo)electrocatalytic reduction of O_(2)to H_(2)O_(2)and NH_(3)generated from N_(2) are discussed.The progress and challenges in above catalytic processes are given.We believe this manuscript will give the researchers more suggestions and help them to obtain useful information in this field.
