Phosphorus(P)is an important nutrient element in the photosynthesis process of plants.The effect of stand age on P nutrient dynamics in subtropical plantations is unclear.In this study,the mechanisms of above-and belo...Phosphorus(P)is an important nutrient element in the photosynthesis process of plants.The effect of stand age on P nutrient dynamics in subtropical plantations is unclear.In this study,the mechanisms of above-and belowground P cycling in subtropical P.massoniana plantations of different stand ages(5,9,19,29 and 35 years)were investigated.The percentage of metabolic P in leaves exhibited an initial rise and subsequent decline with stand age of P.massoniana throughout the growing season,culminating in a metabolic P proportion of 34%–68% in litter.During the non-growing season,the main change in the P components of P.massoniana fine roots was a transition from metabolic P to residual P.Relative to during the growing season,soil ligand P fractions decreased by 7%–22% and exchangeable P fractions increased by 0–16%in the non-growing season.Organ P components tended to decrease with increasing stand age,mainly due to the gradual decrease in soil-bioavailable P,a trend alleviated by litter input.The generation of dissolved P by soil phosphatases would limit the reduction in soilbioavailable P caused by leaf P resorption to some extent.The differences in leaf organ P components between the growing and non-growing seasons are attributed to the allocation of P by the P.massoniana.Overall,the results of this study provide a basis for exploring the mechanisms of soil bioavailable P and soil P enzymemediated organ P component allocation in P.massoniana forests.These findings will help improve the management of P-limited P.massoniana plantations to enhance their productivity.展开更多
Tropical forests store more than half of the world's terrestrial carbon(C)pool and account for one-third of global net primary productivity(NPP).Many terrestrial biosphere models(TBMs)estimate increased productivi...Tropical forests store more than half of the world's terrestrial carbon(C)pool and account for one-third of global net primary productivity(NPP).Many terrestrial biosphere models(TBMs)estimate increased productivity in tropical forests throughout the 21st century due to CO_(2)fertilization.However,phosphorus(P)liaitations on vegetation photosynthesis and productivity could significantly reduce the CO_(2)fertilization effect.Here,we used a carbon-nitrogen-phosphorus coupled model(Dynamic Land Ecosystem Model;DLEM-CNP)with heterogeneous maximum carboxylation rates to examine how P limitation has affected C fluxes in tropical forests during1860-2018.Our model results showed that the inclusion of the P processes enhanced model performance in simulating ecosystem productivity.We further compared the simulations from DLEM-CNP,DLEM-CN,and DLEMC and the results showed that the inclusion of P processes reduced the CO_(2)fertilization effect on gross primary production(GPP)by 25%and 45%,and net ecosystem production(NEP)by 28%and 41%,respectively,relative to CN-only and C-on ly models.From the 1860s to the 2010s,the DLEM-CNP estimated that in tropical forests GPP increased by 17%,plant respiration(Ra)increased by 18%,ecosystem respiration(Rh)increased by 13%,NEP increased by 121%per unit area,respectively.Additionally,factorial experiments with DLEM-CNP showed that the enhanced NPP benefiting from the CO_(2) fertilization effect had been offset by 135%due to deforestation from the 1860s to the 2010s.Our study highlights the importance of P limitation on the C cycle and the weakened CO_(2)fertilization effect resulting from P limitation in tropical forests.展开更多
The crossmodal interaction of different senses,which is an important basis for learning and memory in the human brain,is highly desired to be mimicked at the device level for developing neuromorphic crossmodal percept...The crossmodal interaction of different senses,which is an important basis for learning and memory in the human brain,is highly desired to be mimicked at the device level for developing neuromorphic crossmodal perception,but related researches are scarce.Here,we demonstrate an optoelectronic synapse for vision-olfactory crossmodal perception based on MXene/violet phosphorus(VP)van der Waals heterojunctions.Benefiting from the efficient separation and transport of photogenerated carriers facilitated by conductive MXene,the photoelectric responsivity of VP is dramatically enhanced by 7 orders of magnitude,reaching up to 7.7 A W^(−1).Excited by ultraviolet light,multiple synaptic functions,including excitatory postsynaptic currents,pairedpulse facilitation,short/long-term plasticity and“learning-experience”behavior,were demonstrated with a low power consumption.Furthermore,the proposed optoelectronic synapse exhibits distinct synaptic behaviors in different gas environments,enabling it to simulate the interaction of visual and olfactory information for crossmodal perception.This work demonstrates the great potential of VP in optoelectronics and provides a promising platform for applications such as virtual reality and neurorobotics.展开更多
We investigate the anisotropic band structure and its evolution under tensile strains along different crystallographic directions in bulk black phosphorus(BP)using angle-resolved photoemission spectroscopy and density...We investigate the anisotropic band structure and its evolution under tensile strains along different crystallographic directions in bulk black phosphorus(BP)using angle-resolved photoemission spectroscopy and density functional theory.The results show that there are band crossings in the Z-L(armchair)direction.展开更多
Forest productivity is closely linked to seasonal variations and vertical differentiation in leaf traits.However,leaf structural and chemical traits variation among co-existing species,and plant functional types withi...Forest productivity is closely linked to seasonal variations and vertical differentiation in leaf traits.However,leaf structural and chemical traits variation among co-existing species,and plant functional types within the canopy are poorly quantified.In this study,the seasonality of leaf chlorophyll,nitrogen(N),and phosphorus(P)were quantified vertically along the canopy of four major tree species and two types of herbs in a temperate deciduous forest.The role of shade tolerance in shaping the seasonal variation and vertical differentiation was examined.During the entire season,chlorophyll content showed a distinct asymmetric unimodal pattern for all species,with greater chlorophyll levels in autumn than in spring,and the timing of peak chlorophyll per leaf area gradually decreased as shade tolerance increased.Chlorophyll a:b ratios gradually decreased with increasing shade tolerance.Leaf N and P contents sharply declined during leaf expansion,remained steady in the mature stage and decreased again during leaf senescence.Over the seasons,the lower canopy layer had significantly higher chlorophyll per leaf mass but not chlorophyll per leaf area than the upper canopy layer regardless of degree of shade tolerance.However,N and P per leaf area of intermediate shade-tolerant and fully shade-tolerant tree species were significantly higher in the upper canopy than in the lower.Seasonal variations in N:P ratios suggest changes in N or P limitation.These findings indicate that shade tolerance is a key feature shaping inter-specific differences in leaf chlorophyll,N,and P contents as well as their seasonality in temperate deciduous forests,which have significant implications for modeling leaf photosynthesis and ecosystem production.展开更多
Carbon(C),nitrogen(N),and phosphorus(P)are of fundamental importance for growth and nutrient dynamics within plant organs and deserve more attention at regional to global scales.However,our knowledge of how these nutr...Carbon(C),nitrogen(N),and phosphorus(P)are of fundamental importance for growth and nutrient dynamics within plant organs and deserve more attention at regional to global scales.However,our knowledge of how these nutrients vary with tree size,organ age,or root order at the individual level remains limited.We determined C,N,and P contents and their stoichiometric ratios(i.e.,nutrient traits)in needles,branches,and fine roots at different organ ages(0-3-year-old needles and branches)and root orders(1st-4th order roots)from 64 Pinus koraiensis of varying size(Diameter at breast height ranged from 0.3 to 100 cm)in northeast China.Soil factors were also measured.The results show that nutrient traits were regulated by tree size,organ age,or root order rather than soil factors.At a whole-plant level,nutrient traits decreased in needles and fine roots but increased in branches with tree size.At the organ level,age or root order had a negative effect on C,N,and P and a positive effect on stoichiometric ratios.Our results demonstrate that nutrient variations are closely related to organ-specific functions and ecophysiological processes at an individual level.It is suggested that the nutrient acquisition strategy by younger trees and organ fractions with higher nutrient content is for survival.Conversely,nutrient storage strategy in older trees and organ fractions are mainly for steady growth.Our results clarified the nutrient utilization strategies during tree and organ ontogeny and suggest that tree size and organ age or root order should be simultaneously considered to understand the complexities of nutrient variations.展开更多
Conversions from rural to urban land uses have the potential to greatly modify soil phosphorus （P） levels. Soils in shrubs, Masson pine forest, conifer and broadleaf mixed forest, evergreen broadleaved forest and ba...Conversions from rural to urban land uses have the potential to greatly modify soil phosphorus （P） levels. Soils in shrubs, Masson pine forest, conifer and broadleaf mixed forest, evergreen broadleaved forest and bamboo forest in the mid-subtropical region along an urban-rural gradient in Nanchang City, southern China, were analyzed for total P and P fractions using the modified Hedley P sequential fractionation method. Results show that the topsoil total P and total exactable P concentrations were significantly higher in the urban area （0.71 g·kg^-1 and 378.50 mg·kg^-1, respectively） than in the suburban （0.30 g·kg^-1 and 150.74 mg·kg^-1, respectively） and rural areas （0.31 g·kg^-1 and 147.38 mg·kg^-1, respectively） （p〈0.05）. Among the five P fractions of resin-P, NaHCO3-P NaOH-P, Sonication-P and HCI-P, the relative abundance of HCl-P in urban forest soils （36%） was the highest and also significantly higher than in suburban （8%） and rural soils （6%）, while NaOH-P was the dominant form in suburban （41%） and rural soils （50%）. Phosphorus accumulation in the urban soils could affect the cycle of P in urban forest systems, particularly the HCl-P fraction that might rapidly enrich aquatic systems in urban areas.展开更多
A laboratory simulated freeze-thaw was conducted to determine the effects of freeze-thaw on soil nutrient availability in temperate semi-arid regions. Soil samples were collected from sandy soils （0-20 cm） of three ...A laboratory simulated freeze-thaw was conducted to determine the effects of freeze-thaw on soil nutrient availability in temperate semi-arid regions. Soil samples were collected from sandy soils （0-20 cm） of three typical ecosystems （grassland, Mongolian pine plantation and poplar plantation） in southeastern Keerqin Sandy Lands of China and subjected to freeze-thaw treatment （-12℃ for 10 days, then r 20℃ for 10 days） or incubated at constant temperature （20℃ for 20 days）. Concentrations of the soil NO3^--N, NH4^＋-N, NaHCO3 extractable inorganic P （LPi） and microbial biomass P （MBP） were determined on three occasions： at the start of the incubation, immediate post-thawing and at the 10th day post-thawing. The results showed that soil net nitrification and N mineralization rates at three sites were negatively affected by freeze-thaw treatment, and decreased by 50%-85% as compared to the control, of which the greatest decline occurred in the soil collected from poplar plantation. In contrast, the concentration of soil NH4^＋-N, NaHCO3 extractable inorganic P （LPi） and microbial biomass P were insignificantly influenced by freeze-thaw except that LPi and NH4^＋-N showed a slight increase immediate post-thawing. The effects of freeze-thaw on soil N transformation were related to soil biological processes and the relatively constant available P was ascribed to severe soil aridity.展开更多
We investigated the patterns of phosphorus transport from purple-soil cropland of 5° and 10° slopes with bare and vegetated surfaces,respectively.Each type of land was tested under a simulated moderate rainf...We investigated the patterns of phosphorus transport from purple-soil cropland of 5° and 10° slopes with bare and vegetated surfaces,respectively.Each type of land was tested under a simulated moderate rainfall of 0.33 mm/min,a downfall of 0.90 mm/min,and a rainstorm of 1.86 mm/min.Runoff dynamics and changes in the export amount of phosphorus are influenced by the rainfall intensity,the slope and surface conditions of cropland.The vegetation diverts rain water from the surface into soil and helps the formation of a subsurface runoff,but has little influence on runoff process at the same sloping degree.Vegetated soil has a smaller phosphorous loss,particularly much less in the particulate form.A heavier rainfall flushes away more phosphorous.Rainwater percolating soil carries more dissolved phosphorous than particulate phosphorous.Understanding the patterns of phosphorous transport under various conditions from purple soil in the middle of Sichuan basin is helpful for developing countermeasures against non-point-source pollution resulting in the eutrophication of water bodies in this region that could,if not controlled properly,deteriorate the water quality of the Three Gorges Reservoir.展开更多
To assess phosphorus(P)status of forest soil under naturally restored vegetation,P fractions in the 10-cm soil layer were quantified at different successional stages on the clear-cut site of mixed broadleaved and Kore...To assess phosphorus(P)status of forest soil under naturally restored vegetation,P fractions in the 10-cm soil layer were quantified at different successional stages on the clear-cut site of mixed broadleaved and Korean pine forest.Four communities of shrub,softwood broad-leaved forest,softwood and hardwood broad-leaved forest,and hardwood broad-leaved forest represented different successional stages.A soil sample from a primary broad-leaved and Korean pine stand was the control.A sequential P fractionation scheme extracted empirically defined pools of P and path analysis used to partition the direct and indirect contribution of soil P fractions to available P.The results show that available P increased significantly with long-term succession,while both sodium bicarbonate-extractable P(NaHCO_(3)-P)and sodium hydroxide-extractable P(NaOHP)fractions were reduced in early successional stages and increased in late stages.Compared to the primary forest,concentrations of P fractions in the four stages significantly decreased except for HCl-P,indicating that soil P supplements over the long-term did not return to primary forest levels.The results of related analysis also showed that NaHCO_(3)-P_(i)levels were significantly related to available phosphorus.According to the path analysis coefficient,NaHCO_(3)-P_(i)exhibited the highest effect on available P among eight P fractions;the indirect effects of other P fractions via NaHCO_(3)-P_(i)were larger than those with other P fractions.Overall,this study suggests that soil P bioavailability gradually improved during natural vegetation restoration on clear-cut sites mainly through the increase of NaHCO_(3)-P,where phosphorous is immediately available,and subsequently available phosphorus Na OH-P.展开更多
From September 1999 to July 2000, N and P concentrations of fine roots were measured with the method of sequential soil core at bimonthly intervals in a mixed forest of Tsoong's tree (Tsoongiodendron odorum Chun) ...From September 1999 to July 2000, N and P concentrations of fine roots were measured with the method of sequential soil core at bimonthly intervals in a mixed forest of Tsoong's tree (Tsoongiodendron odorum Chun) and Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) in Sanming, Fujian. The results showed that N, P concentration of Chinese fir and Tsoong's tree in fine roots were negatively related to root diameter size. The concentrations of N and P in living roots and dead roots were compared. The order of N concentration in fine roots in different samples was Tsoong's tree>undergrowth>Chinese fir, while that of P was undergrowth>Tsoong's tree>Chinese fir. For Chinese fir, the seasonal change of N, P concentrations in fine roots with various diameter classes showed a single-apex curve with a maximum in September. For Tsoong's tree, maximized concentration of N in fine roots appeared in July or September and maximized P concentration in May.展开更多
Changes in phosphorus （P） fractions in a P deficient allophanic soil under P. radiata seedlings grown with broom （Cytisus scoparius L.） and ryegrass （Lolium multiflorum） in pots were studied 14 months after the ...Changes in phosphorus （P） fractions in a P deficient allophanic soil under P. radiata seedlings grown with broom （Cytisus scoparius L.） and ryegrass （Lolium multiflorum） in pots were studied 14 months after the application of triple superphosphate at the rates of 0, 50, and 100 pg.g^-1, to determine the fate of fertiliser-derived P in the rhizosphere soils. Application of P fertiliser increased NaOH-Pi, NaOH-Po, and H2SO4-Pi concentrations in the soil, but decreased the residual-P concentration. The resin-Pi concentration, which is ex- tremely low in this soil （1 to μgg^-1 ）, remained the same. The majority of the added fertiliser P was however recovered in the NaOH-Pi fraction （40%-49%）. This is due to the high P fixation in this soil （92%）. The second highest P recovery was in NaOH-Po fraction （7%-19%）. Under P deficient condition or addition at the rate of 0 μg.g^-6, the NaOH-Pi concentration in the radiata rhizosphere soil was lower than that in the bulk soil and broom and grass rhizosphere soils. This may be due to higher oxalate production by the roots and mycorrhiza under P deficient conditions which released some ＆the P fixed to the soils in the rhizosphere, which needs to be tested in future studies.展开更多
The presence of a thatch layer in established pastures could reduce the contact between broiler litter and soil, thus increasing the potential for surface runoff contamination with litter P. We conducted a laboratory ...The presence of a thatch layer in established pastures could reduce the contact between broiler litter and soil, thus increasing the potential for surface runoff contamination with litter P. We conducted a laboratory study to evaluate the effect of a thatch layer on the dynamics of water-soluble P in undisturbed cores taken from a pasture. Cores with and without a thatch layer received a surface application of broiler litter (5 thm-2) and were incubated at 25 oC for 56 d. The result showed that on the soil surface the contents of water soluble-P (39 kghm-2) of the cores with the thatch layer was higher than that (20 kghm-2) of the cores without the thatch layer. Therefore on well-established pastures fertilized with broiler litter, the presence of a thatch layer might lead to high concentrations of water-soluble P on the soil surface.展开更多
Changes in phosphorus (P) fractions in a P deficient allophanic soil under P. radiata seedlings grown with broom (Cytisus scoparius L.) and ryegrass (Lolium multiflorum) in pots were studied 14 months after the applic...Changes in phosphorus (P) fractions in a P deficient allophanic soil under P. radiata seedlings grown with broom (Cytisus scoparius L.) and ryegrass (Lolium multiflorum) in pots were studied 14 months after the application of triple superphosphate at the rates of 0, 50, and 100 μg·g-1, to determine the fate of fertiliser-derived P in the rhizosphere soils. Application of P fertiliser increased NaOH-Pi, NaOH-Po, and H2SO4-Pi concentrations in the soil, but decreased the residual-P concentration. The resin-Pi concentration, which is extremely low in this soil (1 to 3 μg·g-1 ), remained the same. The majority of the added fertiliser P was however recovered in the NaOH-Pi fraction (40%?49%). This is due to the high P fixation in this soil (92%). The second highest P recovery was in NaOH-Po fraction (7%?19%). Under P deficient condition or addition at the rate of 0 μg·g-1, the NaOH-Pi concentration in the radiata rhizosphere soil was lower than that in the bulk soil and broom and grass rhizosphere soils. This may be due to higher oxalate production by the roots and mycorrhiza under P deficient conditions which released some of the P fixed to the soils in the rhizosphere, which needs to be tested in future studies.展开更多
The application of phosphorus(P)to soil can increase its availability to plants and alter P fractions in annual and perennial organs of Cordia trichotoma.If a portion of P accumulates in perennial organs in organic fr...The application of phosphorus(P)to soil can increase its availability to plants and alter P fractions in annual and perennial organs of Cordia trichotoma.If a portion of P accumulates in perennial organs in organic fractions it can be used in the next growth season,possibly decreasing plant dependence on P derived from soil fertilization.However,if P is preferentially accumulated in inorganic fractions in annual organs,plants will be more dependent on phosphate fertilization.This study aimed to evaluate the distribution of P fractions in organs of C.trichotoma grown on sandy soil treated with 120 and 360 kg P2O5 ha^(−1).The control was a zero application.After 24 months following fertilization,C.trichotoma seedlings were cut and separated into leaves,branches,stems and roots,dried,ground and subjected to chemical fractionation of P,which estimates fractions of total soluble P,soluble inorganic and organic P,lipid P,P associated ribonucleic acid and deoxyribonucleic acid,and residual P.P in annual organs,as leaves,accumulated preferentially in the soluble inorganic fraction in both treatments.In perennial organs such as stems and branches,P accumulated preferentially in the soluble organic fraction.The application of 300%of the recommended dosage(360 kg P2O5 ha^(−1))promoted the accumulation of P in soluble organic fractions which may contribute to annual growth the following season and be a strategy to reduce the dependence of 2-year-old stands on soil-derived P and on fertilizers.展开更多
A series of phosphorus-modified PITQ-13 catalysts was prepared by wet impregnation of NH4H2PO4 solution into an HITQ-13 parent. The catalysts were characterized using XRD, N2 adsorption, MAS NMR and NH3-TPD. Their cat...A series of phosphorus-modified PITQ-13 catalysts was prepared by wet impregnation of NH4H2PO4 solution into an HITQ-13 parent. The catalysts were characterized using XRD, N2 adsorption, MAS NMR and NH3-TPD. Their catalytic performance in 1-butene catalytic cracking was evaluated in a fixed fluidized bed reactor. The results showed that the crystallinity, surface area and pore volume of P-modified PITQ-13 catalysts decreased with the increasing amounts of P. The number of weak acid sites increased, whereas that of strong acidity decreased. The selectivity to propylene in 1-butene cracking reactions increased because of the decrease in strong acidity. The yield of propylene achieved 41.6% over PITQ-13-2 catalyst with a P content of 1.0 wt%, which was 5.1% greater than that achieved over HITQ-13 catalyst.展开更多
Plantations of eucalypts as short-rotation tree crops are rapidly expanding in tropical and sub-tropical regions, including southern China, where the soils are acidic and available phosphorus （P） is limited. We inve...Plantations of eucalypts as short-rotation tree crops are rapidly expanding in tropical and sub-tropical regions, including southern China, where the soils are acidic and available phosphorus （P） is limited. We investigated seedling growth, dry matter accumulation, and the dynamics of photosynthetic rate and chlorophyll content of seven Eucalyptus spe- cies/hybrids （E. dunnii, E. grandis, E. grandis x E. camaldulensis, E. urophylla x E. camaldulensis, E. urophylla x E. tereticornis, E. grandis x E. tereticornis, E. urophylla x E. grandis） in response to different levels of P supply （0, 6, 12 and 18 mg-kg-l KH2PO4）. The photosynthetic rate and the chlorophyll content significantly declined as the P supply declined in almost a linear fashion for all species as the P stress period extended. In the absence of P supply, height growth of seedlings of all species was significantly impaired, while root collar diameter growth and whole plant dry matter accumulation was not affected by the level of P supply in most of the species. Significant inter-species variations in growth, dry matter accumulation and photosynthetic rate in response to P supply were detected. Eucalyptus dunnii had the lowest growth perform- ance across all levels of P supply while E. urophylla x E. tereticornis showed superior growth performance. From a practical point of view, E. urophylla x E. tereticornis is suggested as a candidate hybrid for planting on slightly P-deficient sites in southern China while E. dunnii, being a slow-growing species, is not suitable for short-rotation plantation. On plantation sites where severe P deficiency exists, P fertilization needs to be considered to boost rapid growth of seedlings so as to meet the man- agement objectives of short-rotation plantation.展开更多
Although carbon(C), nitrogen(N), and phosphorous(P) stoichiometric ratios are considered good indicators of nutrient excess/limitation and thus of ecosystem health, few reports have discussed the trends and the recipr...Although carbon(C), nitrogen(N), and phosphorous(P) stoichiometric ratios are considered good indicators of nutrient excess/limitation and thus of ecosystem health, few reports have discussed the trends and the reciprocal effects of C:N:P stoichiometry in plant–litter–soil systems. The present study analyzed C:N:P ratios in four age groups of Chinese pine, Pinus tabulaeformis Carr., forests in Shanxi Province, China: plantation young forests(AY,<20 year-old); plantation middle-aged forests(AM, 21–30 year-old); natural young forests(NY,<30 year-old); and natural middle-aged forests(NM,31–50 year-old). The average C:N:P ratios calculated for tree, shrub, and herbaceous leaves, litter, and soil(0–100 cm) were generally higher in NY followed by NM,AM, and AY. C:N and C:P ratios were higher in litter than in leaves and soils, and reached higher values in the litter and leaves of young forests than in middle-aged forests;however, C:N and C:P ratios were higher in soils of middle-aged forests than in young forests. N:P ratios were higher in leaves than in litter and soils regardless of stand age; the consistent N:P<14 values found in all forests indicated N limitations. With plant leaves, C:P ratios were highest in trees, followed by herbs and shrubs, indicating a higher efficiency in tree leaf formation. C:N ratios decreased with increasing soil depth, whereas there was no trend for C:P and N:P ratios. C:N:P stoichiometry of forest foliage did not exhibit a consistent variation according to stand age. Research on the relationships between N:P, and P, N nutrient limits and the characteristics of vegetation nutrient adaptation need to be continued.展开更多
Two-dimensional black phosphorus(2D BP),an emerging material,has aroused tremendous interest once discovered.This is due to the fact that it integrates unprecedented properties of other 2D materials,such as tunable ba...Two-dimensional black phosphorus(2D BP),an emerging material,has aroused tremendous interest once discovered.This is due to the fact that it integrates unprecedented properties of other 2D materials,such as tunable bandgap structures,outstanding electrochemical properties,anisotropic mechanical,thermodynamic,and photoelectric properties,making it of great research value in many fields.The emergence of 2D BP has greatly promoted the development of electrochemical energy storage devices,especially lithium-ion batteries.However,in the application of 2D BP,there are still some problems to be solved urgently,such as the difficulty in the synthesis of large-scale high-quality phosphorene,poor environmental stability,and the volume expansion as electrode materials.Herein,according to the latest research progress of 2D BP in the field of energy storage,we systematically summarize and compare the preparation methods of phosphorene and discuss the basic structure and properties of BP,especially the environmental instability and passivation techniques.In particular,the practical application and challenges of 2D BP as anode material for lithium-ion batteries are analyzed in detail.Finally,some personal perspectives on the future development and challenges of BP are presented.展开更多
Myeloblastosis(MYB) proteins constitute one of the largest transcription factor(TF) families in plants and play crucial roles in regulating plant physiological and biochemical processes, including adaptation to divers...Myeloblastosis(MYB) proteins constitute one of the largest transcription factor(TF) families in plants and play crucial roles in regulating plant physiological and biochemical processes, including adaptation to diverse abiotic stresses. These TF families contain highly conserved MYB repeats(1 R, R2 R3, 3 R and 4 R) at the N-terminus. Roles for MYB TFs have been reported in response to such stresses as dehydration, salt, cold, and drought. The characterization of Masson pine(Pinus massoniana) MYB TFs are reported, including the analysis of MYB TFs expression in seedlings under controlled conditions and two different phosphate(Pi) deficient treatments. By searching for conserved MYB motifs in full transcriptomic RNA sequencing data for P. massoniana, 59 sequences were identified as MYB TFs. Conserved domainstructures and comparative functional and phylogenetic relationships of these MYB TFs with those in Arabidopsis were assessed using various bioinformatics tools. Based on microarray analysis, P. massoniana MYB genes exhibited different expression patterns under the two Pi deficiency conditions. Genes encoding MYB TFs that showed increased expression under critical Pi deficiency were identified, and some MYBs were differentially expressed only under conditions of severe Pi starvation. These results are useful for the functional characterization of MYB TFs that may be involved in the response to Pi deficiency and play divergent roles in plants.展开更多
基金supported by the Fundamental Research Funds for the Central Non-profit Research Institution(CAFYBB2021QD002-2 and CAFYBB2020ZE001)the National Key Research and Development Program of China(2023YFD2200404-02)the Qianjiangyuan National Forest Ecological Research Station.
文摘Phosphorus(P)is an important nutrient element in the photosynthesis process of plants.The effect of stand age on P nutrient dynamics in subtropical plantations is unclear.In this study,the mechanisms of above-and belowground P cycling in subtropical P.massoniana plantations of different stand ages(5,9,19,29 and 35 years)were investigated.The percentage of metabolic P in leaves exhibited an initial rise and subsequent decline with stand age of P.massoniana throughout the growing season,culminating in a metabolic P proportion of 34%–68% in litter.During the non-growing season,the main change in the P components of P.massoniana fine roots was a transition from metabolic P to residual P.Relative to during the growing season,soil ligand P fractions decreased by 7%–22% and exchangeable P fractions increased by 0–16%in the non-growing season.Organ P components tended to decrease with increasing stand age,mainly due to the gradual decrease in soil-bioavailable P,a trend alleviated by litter input.The generation of dissolved P by soil phosphatases would limit the reduction in soilbioavailable P caused by leaf P resorption to some extent.The differences in leaf organ P components between the growing and non-growing seasons are attributed to the allocation of P by the P.massoniana.Overall,the results of this study provide a basis for exploring the mechanisms of soil bioavailable P and soil P enzymemediated organ P component allocation in P.massoniana forests.These findings will help improve the management of P-limited P.massoniana plantations to enhance their productivity.
基金partially supported by the US National Science Foundation(1903722,1243232)。
文摘Tropical forests store more than half of the world's terrestrial carbon(C)pool and account for one-third of global net primary productivity(NPP).Many terrestrial biosphere models(TBMs)estimate increased productivity in tropical forests throughout the 21st century due to CO_(2)fertilization.However,phosphorus(P)liaitations on vegetation photosynthesis and productivity could significantly reduce the CO_(2)fertilization effect.Here,we used a carbon-nitrogen-phosphorus coupled model(Dynamic Land Ecosystem Model;DLEM-CNP)with heterogeneous maximum carboxylation rates to examine how P limitation has affected C fluxes in tropical forests during1860-2018.Our model results showed that the inclusion of the P processes enhanced model performance in simulating ecosystem productivity.We further compared the simulations from DLEM-CNP,DLEM-CN,and DLEMC and the results showed that the inclusion of P processes reduced the CO_(2)fertilization effect on gross primary production(GPP)by 25%and 45%,and net ecosystem production(NEP)by 28%and 41%,respectively,relative to CN-only and C-on ly models.From the 1860s to the 2010s,the DLEM-CNP estimated that in tropical forests GPP increased by 17%,plant respiration(Ra)increased by 18%,ecosystem respiration(Rh)increased by 13%,NEP increased by 121%per unit area,respectively.Additionally,factorial experiments with DLEM-CNP showed that the enhanced NPP benefiting from the CO_(2) fertilization effect had been offset by 135%due to deforestation from the 1860s to the 2010s.Our study highlights the importance of P limitation on the C cycle and the weakened CO_(2)fertilization effect resulting from P limitation in tropical forests.
基金supported by National Natural Science Foundation of China(No.51902250).
文摘The crossmodal interaction of different senses,which is an important basis for learning and memory in the human brain,is highly desired to be mimicked at the device level for developing neuromorphic crossmodal perception,but related researches are scarce.Here,we demonstrate an optoelectronic synapse for vision-olfactory crossmodal perception based on MXene/violet phosphorus(VP)van der Waals heterojunctions.Benefiting from the efficient separation and transport of photogenerated carriers facilitated by conductive MXene,the photoelectric responsivity of VP is dramatically enhanced by 7 orders of magnitude,reaching up to 7.7 A W^(−1).Excited by ultraviolet light,multiple synaptic functions,including excitatory postsynaptic currents,pairedpulse facilitation,short/long-term plasticity and“learning-experience”behavior,were demonstrated with a low power consumption.Furthermore,the proposed optoelectronic synapse exhibits distinct synaptic behaviors in different gas environments,enabling it to simulate the interaction of visual and olfactory information for crossmodal perception.This work demonstrates the great potential of VP in optoelectronics and provides a promising platform for applications such as virtual reality and neurorobotics.
基金supported by the National Natural Science Foundation of China(Grant Nos.12104216,12241403,and 61974061)the National Key R&D Program of China(Grant No.2021YFB3601600)the Natural Science Foundation of Jiangsu Province of China(Grant No.BK20140054)。
文摘We investigate the anisotropic band structure and its evolution under tensile strains along different crystallographic directions in bulk black phosphorus(BP)using angle-resolved photoemission spectroscopy and density functional theory.The results show that there are band crossings in the Z-L(armchair)direction.
基金This work was supported by the National Natural Science Foundation of China(32171765).
文摘Forest productivity is closely linked to seasonal variations and vertical differentiation in leaf traits.However,leaf structural and chemical traits variation among co-existing species,and plant functional types within the canopy are poorly quantified.In this study,the seasonality of leaf chlorophyll,nitrogen(N),and phosphorus(P)were quantified vertically along the canopy of four major tree species and two types of herbs in a temperate deciduous forest.The role of shade tolerance in shaping the seasonal variation and vertical differentiation was examined.During the entire season,chlorophyll content showed a distinct asymmetric unimodal pattern for all species,with greater chlorophyll levels in autumn than in spring,and the timing of peak chlorophyll per leaf area gradually decreased as shade tolerance increased.Chlorophyll a:b ratios gradually decreased with increasing shade tolerance.Leaf N and P contents sharply declined during leaf expansion,remained steady in the mature stage and decreased again during leaf senescence.Over the seasons,the lower canopy layer had significantly higher chlorophyll per leaf mass but not chlorophyll per leaf area than the upper canopy layer regardless of degree of shade tolerance.However,N and P per leaf area of intermediate shade-tolerant and fully shade-tolerant tree species were significantly higher in the upper canopy than in the lower.Seasonal variations in N:P ratios suggest changes in N or P limitation.These findings indicate that shade tolerance is a key feature shaping inter-specific differences in leaf chlorophyll,N,and P contents as well as their seasonality in temperate deciduous forests,which have significant implications for modeling leaf photosynthesis and ecosystem production.
基金supported by the National Key R&D Program of China (2022YFD2201100)Natural Science Foundation of Heilongjiang Province of China (TD2023C006)the Fundamental Research Funds for the Central Universities (2572022DS13).
文摘Carbon(C),nitrogen(N),and phosphorus(P)are of fundamental importance for growth and nutrient dynamics within plant organs and deserve more attention at regional to global scales.However,our knowledge of how these nutrients vary with tree size,organ age,or root order at the individual level remains limited.We determined C,N,and P contents and their stoichiometric ratios(i.e.,nutrient traits)in needles,branches,and fine roots at different organ ages(0-3-year-old needles and branches)and root orders(1st-4th order roots)from 64 Pinus koraiensis of varying size(Diameter at breast height ranged from 0.3 to 100 cm)in northeast China.Soil factors were also measured.The results show that nutrient traits were regulated by tree size,organ age,or root order rather than soil factors.At a whole-plant level,nutrient traits decreased in needles and fine roots but increased in branches with tree size.At the organ level,age or root order had a negative effect on C,N,and P and a positive effect on stoichiometric ratios.Our results demonstrate that nutrient variations are closely related to organ-specific functions and ecophysiological processes at an individual level.It is suggested that the nutrient acquisition strategy by younger trees and organ fractions with higher nutrient content is for survival.Conversely,nutrient storage strategy in older trees and organ fractions are mainly for steady growth.Our results clarified the nutrient utilization strategies during tree and organ ontogeny and suggest that tree size and organ age or root order should be simultaneously considered to understand the complexities of nutrient variations.
基金funded by the National Natural Science Foundation of China(No.3060047&30960311)Natural Science Foundation of Jiangxi Provinces(No.2007GQN1935)
文摘Conversions from rural to urban land uses have the potential to greatly modify soil phosphorus （P） levels. Soils in shrubs, Masson pine forest, conifer and broadleaf mixed forest, evergreen broadleaved forest and bamboo forest in the mid-subtropical region along an urban-rural gradient in Nanchang City, southern China, were analyzed for total P and P fractions using the modified Hedley P sequential fractionation method. Results show that the topsoil total P and total exactable P concentrations were significantly higher in the urban area （0.71 g·kg^-1 and 378.50 mg·kg^-1, respectively） than in the suburban （0.30 g·kg^-1 and 150.74 mg·kg^-1, respectively） and rural areas （0.31 g·kg^-1 and 147.38 mg·kg^-1, respectively） （p〈0.05）. Among the five P fractions of resin-P, NaHCO3-P NaOH-P, Sonication-P and HCI-P, the relative abundance of HCl-P in urban forest soils （36%） was the highest and also significantly higher than in suburban （8%） and rural soils （6%）, while NaOH-P was the dominant form in suburban （41%） and rural soils （50%）. Phosphorus accumulation in the urban soils could affect the cycle of P in urban forest systems, particularly the HCl-P fraction that might rapidly enrich aquatic systems in urban areas.
基金the grants from the National Natural Science Foundation of China (No. 30471377)the National Key Basic Research Program of China (No. 2007CB106803)the National Key Technologies R & D Program of China (No. 2006BAD26B0201-1)
文摘A laboratory simulated freeze-thaw was conducted to determine the effects of freeze-thaw on soil nutrient availability in temperate semi-arid regions. Soil samples were collected from sandy soils （0-20 cm） of three typical ecosystems （grassland, Mongolian pine plantation and poplar plantation） in southeastern Keerqin Sandy Lands of China and subjected to freeze-thaw treatment （-12℃ for 10 days, then r 20℃ for 10 days） or incubated at constant temperature （20℃ for 20 days）. Concentrations of the soil NO3^--N, NH4^＋-N, NaHCO3 extractable inorganic P （LPi） and microbial biomass P （MBP） were determined on three occasions： at the start of the incubation, immediate post-thawing and at the 10th day post-thawing. The results showed that soil net nitrification and N mineralization rates at three sites were negatively affected by freeze-thaw treatment, and decreased by 50%-85% as compared to the control, of which the greatest decline occurred in the soil collected from poplar plantation. In contrast, the concentration of soil NH4^＋-N, NaHCO3 extractable inorganic P （LPi） and microbial biomass P were insignificantly influenced by freeze-thaw except that LPi and NH4^＋-N showed a slight increase immediate post-thawing. The effects of freeze-thaw on soil N transformation were related to soil biological processes and the relatively constant available P was ascribed to severe soil aridity.
基金the Natural Science Foundation of China (No. 40571093)the National Field Station Fund
文摘We investigated the patterns of phosphorus transport from purple-soil cropland of 5° and 10° slopes with bare and vegetated surfaces,respectively.Each type of land was tested under a simulated moderate rainfall of 0.33 mm/min,a downfall of 0.90 mm/min,and a rainstorm of 1.86 mm/min.Runoff dynamics and changes in the export amount of phosphorus are influenced by the rainfall intensity,the slope and surface conditions of cropland.The vegetation diverts rain water from the surface into soil and helps the formation of a subsurface runoff,but has little influence on runoff process at the same sloping degree.Vegetated soil has a smaller phosphorous loss,particularly much less in the particulate form.A heavier rainfall flushes away more phosphorous.Rainwater percolating soil carries more dissolved phosphorous than particulate phosphorous.Understanding the patterns of phosphorous transport under various conditions from purple soil in the middle of Sichuan basin is helpful for developing countermeasures against non-point-source pollution resulting in the eutrophication of water bodies in this region that could,if not controlled properly,deteriorate the water quality of the Three Gorges Reservoir.
基金supported by the National Forestry Industry Public Welfare Projects(grant number 201404202)。
文摘To assess phosphorus(P)status of forest soil under naturally restored vegetation,P fractions in the 10-cm soil layer were quantified at different successional stages on the clear-cut site of mixed broadleaved and Korean pine forest.Four communities of shrub,softwood broad-leaved forest,softwood and hardwood broad-leaved forest,and hardwood broad-leaved forest represented different successional stages.A soil sample from a primary broad-leaved and Korean pine stand was the control.A sequential P fractionation scheme extracted empirically defined pools of P and path analysis used to partition the direct and indirect contribution of soil P fractions to available P.The results show that available P increased significantly with long-term succession,while both sodium bicarbonate-extractable P(NaHCO_(3)-P)and sodium hydroxide-extractable P(NaOHP)fractions were reduced in early successional stages and increased in late stages.Compared to the primary forest,concentrations of P fractions in the four stages significantly decreased except for HCl-P,indicating that soil P supplements over the long-term did not return to primary forest levels.The results of related analysis also showed that NaHCO_(3)-P_(i)levels were significantly related to available phosphorus.According to the path analysis coefficient,NaHCO_(3)-P_(i)exhibited the highest effect on available P among eight P fractions;the indirect effects of other P fractions via NaHCO_(3)-P_(i)were larger than those with other P fractions.Overall,this study suggests that soil P bioavailability gradually improved during natural vegetation restoration on clear-cut sites mainly through the increase of NaHCO_(3)-P,where phosphorous is immediately available,and subsequently available phosphorus Na OH-P.
基金The Foundation of Post-doctoral Research of China (1999, No 10), the Foundation for University Key Teacher by the Ministry of Ed
文摘From September 1999 to July 2000, N and P concentrations of fine roots were measured with the method of sequential soil core at bimonthly intervals in a mixed forest of Tsoong's tree (Tsoongiodendron odorum Chun) and Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) in Sanming, Fujian. The results showed that N, P concentration of Chinese fir and Tsoong's tree in fine roots were negatively related to root diameter size. The concentrations of N and P in living roots and dead roots were compared. The order of N concentration in fine roots in different samples was Tsoong's tree>undergrowth>Chinese fir, while that of P was undergrowth>Tsoong's tree>Chinese fir. For Chinese fir, the seasonal change of N, P concentrations in fine roots with various diameter classes showed a single-apex curve with a maximum in September. For Tsoong's tree, maximized concentration of N in fine roots appeared in July or September and maximized P concentration in May.
文摘Changes in phosphorus （P） fractions in a P deficient allophanic soil under P. radiata seedlings grown with broom （Cytisus scoparius L.） and ryegrass （Lolium multiflorum） in pots were studied 14 months after the application of triple superphosphate at the rates of 0, 50, and 100 pg.g^-1, to determine the fate of fertiliser-derived P in the rhizosphere soils. Application of P fertiliser increased NaOH-Pi, NaOH-Po, and H2SO4-Pi concentrations in the soil, but decreased the residual-P concentration. The resin-Pi concentration, which is ex- tremely low in this soil （1 to μgg^-1 ）, remained the same. The majority of the added fertiliser P was however recovered in the NaOH-Pi fraction （40%-49%）. This is due to the high P fixation in this soil （92%）. The second highest P recovery was in NaOH-Po fraction （7%-19%）. Under P deficient condition or addition at the rate of 0 μg.g^-6, the NaOH-Pi concentration in the radiata rhizosphere soil was lower than that in the bulk soil and broom and grass rhizosphere soils. This may be due to higher oxalate production by the roots and mycorrhiza under P deficient conditions which released some ＆the P fixed to the soils in the rhizosphere, which needs to be tested in future studies.
文摘The presence of a thatch layer in established pastures could reduce the contact between broiler litter and soil, thus increasing the potential for surface runoff contamination with litter P. We conducted a laboratory study to evaluate the effect of a thatch layer on the dynamics of water-soluble P in undisturbed cores taken from a pasture. Cores with and without a thatch layer received a surface application of broiler litter (5 thm-2) and were incubated at 25 oC for 56 d. The result showed that on the soil surface the contents of water soluble-P (39 kghm-2) of the cores with the thatch layer was higher than that (20 kghm-2) of the cores without the thatch layer. Therefore on well-established pastures fertilized with broiler litter, the presence of a thatch layer might lead to high concentrations of water-soluble P on the soil surface.
基金supported by Centre for Sustainable Forest Management at Forest Research Institute, New Zealand
文摘Changes in phosphorus (P) fractions in a P deficient allophanic soil under P. radiata seedlings grown with broom (Cytisus scoparius L.) and ryegrass (Lolium multiflorum) in pots were studied 14 months after the application of triple superphosphate at the rates of 0, 50, and 100 μg·g-1, to determine the fate of fertiliser-derived P in the rhizosphere soils. Application of P fertiliser increased NaOH-Pi, NaOH-Po, and H2SO4-Pi concentrations in the soil, but decreased the residual-P concentration. The resin-Pi concentration, which is extremely low in this soil (1 to 3 μg·g-1 ), remained the same. The majority of the added fertiliser P was however recovered in the NaOH-Pi fraction (40%?49%). This is due to the high P fixation in this soil (92%). The second highest P recovery was in NaOH-Po fraction (7%?19%). Under P deficient condition or addition at the rate of 0 μg·g-1, the NaOH-Pi concentration in the radiata rhizosphere soil was lower than that in the bulk soil and broom and grass rhizosphere soils. This may be due to higher oxalate production by the roots and mycorrhiza under P deficient conditions which released some of the P fixed to the soils in the rhizosphere, which needs to be tested in future studies.
基金financed in part by the Conselho Nacional de Desenvolvimento Cientifico e Tecnologico(CNPq)the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior-Brasil(CAPES)。
文摘The application of phosphorus(P)to soil can increase its availability to plants and alter P fractions in annual and perennial organs of Cordia trichotoma.If a portion of P accumulates in perennial organs in organic fractions it can be used in the next growth season,possibly decreasing plant dependence on P derived from soil fertilization.However,if P is preferentially accumulated in inorganic fractions in annual organs,plants will be more dependent on phosphate fertilization.This study aimed to evaluate the distribution of P fractions in organs of C.trichotoma grown on sandy soil treated with 120 and 360 kg P2O5 ha^(−1).The control was a zero application.After 24 months following fertilization,C.trichotoma seedlings were cut and separated into leaves,branches,stems and roots,dried,ground and subjected to chemical fractionation of P,which estimates fractions of total soluble P,soluble inorganic and organic P,lipid P,P associated ribonucleic acid and deoxyribonucleic acid,and residual P.P in annual organs,as leaves,accumulated preferentially in the soluble inorganic fraction in both treatments.In perennial organs such as stems and branches,P accumulated preferentially in the soluble organic fraction.The application of 300%of the recommended dosage(360 kg P2O5 ha^(−1))promoted the accumulation of P in soluble organic fractions which may contribute to annual growth the following season and be a strategy to reduce the dependence of 2-year-old stands on soil-derived P and on fertilizers.
基金supported by PetroChina Company Limited(12-09-01-01)the National Basic Research Program of China(973 Program,2012CB215001)
文摘A series of phosphorus-modified PITQ-13 catalysts was prepared by wet impregnation of NH4H2PO4 solution into an HITQ-13 parent. The catalysts were characterized using XRD, N2 adsorption, MAS NMR and NH3-TPD. Their catalytic performance in 1-butene catalytic cracking was evaluated in a fixed fluidized bed reactor. The results showed that the crystallinity, surface area and pore volume of P-modified PITQ-13 catalysts decreased with the increasing amounts of P. The number of weak acid sites increased, whereas that of strong acidity decreased. The selectivity to propylene in 1-butene cracking reactions increased because of the decrease in strong acidity. The yield of propylene achieved 41.6% over PITQ-13-2 catalyst with a P content of 1.0 wt%, which was 5.1% greater than that achieved over HITQ-13 catalyst.
基金supported by Forestry Bureau of China(Grant No.2011-4-59,No.201304303)National Natural Science Foundation of China(Grant No.31100472)the Training Program Foundation for University Distinguished Young Talents of Fujian Province,China(Grant No.JA12091)
文摘Plantations of eucalypts as short-rotation tree crops are rapidly expanding in tropical and sub-tropical regions, including southern China, where the soils are acidic and available phosphorus （P） is limited. We investigated seedling growth, dry matter accumulation, and the dynamics of photosynthetic rate and chlorophyll content of seven Eucalyptus spe- cies/hybrids （E. dunnii, E. grandis, E. grandis x E. camaldulensis, E. urophylla x E. camaldulensis, E. urophylla x E. tereticornis, E. grandis x E. tereticornis, E. urophylla x E. grandis） in response to different levels of P supply （0, 6, 12 and 18 mg-kg-l KH2PO4）. The photosynthetic rate and the chlorophyll content significantly declined as the P supply declined in almost a linear fashion for all species as the P stress period extended. In the absence of P supply, height growth of seedlings of all species was significantly impaired, while root collar diameter growth and whole plant dry matter accumulation was not affected by the level of P supply in most of the species. Significant inter-species variations in growth, dry matter accumulation and photosynthetic rate in response to P supply were detected. Eucalyptus dunnii had the lowest growth perform- ance across all levels of P supply while E. urophylla x E. tereticornis showed superior growth performance. From a practical point of view, E. urophylla x E. tereticornis is suggested as a candidate hybrid for planting on slightly P-deficient sites in southern China while E. dunnii, being a slow-growing species, is not suitable for short-rotation plantation. On plantation sites where severe P deficiency exists, P fertilization needs to be considered to boost rapid growth of seedlings so as to meet the man- agement objectives of short-rotation plantation.
基金supported by the ‘‘Doctoral Scientific Research Foundation’’ of Heilongjiang Bayi Agricultural University,Grant No.XDB2015-02 and the ‘‘Strategic Priority Research Program’’ of the Chinese Academy of Sciences,Grant No.XDA05050203-04-01
文摘Although carbon(C), nitrogen(N), and phosphorous(P) stoichiometric ratios are considered good indicators of nutrient excess/limitation and thus of ecosystem health, few reports have discussed the trends and the reciprocal effects of C:N:P stoichiometry in plant–litter–soil systems. The present study analyzed C:N:P ratios in four age groups of Chinese pine, Pinus tabulaeformis Carr., forests in Shanxi Province, China: plantation young forests(AY,<20 year-old); plantation middle-aged forests(AM, 21–30 year-old); natural young forests(NY,<30 year-old); and natural middle-aged forests(NM,31–50 year-old). The average C:N:P ratios calculated for tree, shrub, and herbaceous leaves, litter, and soil(0–100 cm) were generally higher in NY followed by NM,AM, and AY. C:N and C:P ratios were higher in litter than in leaves and soils, and reached higher values in the litter and leaves of young forests than in middle-aged forests;however, C:N and C:P ratios were higher in soils of middle-aged forests than in young forests. N:P ratios were higher in leaves than in litter and soils regardless of stand age; the consistent N:P<14 values found in all forests indicated N limitations. With plant leaves, C:P ratios were highest in trees, followed by herbs and shrubs, indicating a higher efficiency in tree leaf formation. C:N ratios decreased with increasing soil depth, whereas there was no trend for C:P and N:P ratios. C:N:P stoichiometry of forest foliage did not exhibit a consistent variation according to stand age. Research on the relationships between N:P, and P, N nutrient limits and the characteristics of vegetation nutrient adaptation need to be continued.
基金the national science foundation of China(Nos.21373074 and 61675061)。
文摘Two-dimensional black phosphorus(2D BP),an emerging material,has aroused tremendous interest once discovered.This is due to the fact that it integrates unprecedented properties of other 2D materials,such as tunable bandgap structures,outstanding electrochemical properties,anisotropic mechanical,thermodynamic,and photoelectric properties,making it of great research value in many fields.The emergence of 2D BP has greatly promoted the development of electrochemical energy storage devices,especially lithium-ion batteries.However,in the application of 2D BP,there are still some problems to be solved urgently,such as the difficulty in the synthesis of large-scale high-quality phosphorene,poor environmental stability,and the volume expansion as electrode materials.Herein,according to the latest research progress of 2D BP in the field of energy storage,we systematically summarize and compare the preparation methods of phosphorene and discuss the basic structure and properties of BP,especially the environmental instability and passivation techniques.In particular,the practical application and challenges of 2D BP as anode material for lithium-ion batteries are analyzed in detail.Finally,some personal perspectives on the future development and challenges of BP are presented.
基金funded by the Natural Science Foundation of Guizhou Province,P.R.China(20161051)the National Natural Science Foundation of China(31660185)the Doctoral Fund Project of Guizhou University,P.R.China(201464)。
文摘Myeloblastosis(MYB) proteins constitute one of the largest transcription factor(TF) families in plants and play crucial roles in regulating plant physiological and biochemical processes, including adaptation to diverse abiotic stresses. These TF families contain highly conserved MYB repeats(1 R, R2 R3, 3 R and 4 R) at the N-terminus. Roles for MYB TFs have been reported in response to such stresses as dehydration, salt, cold, and drought. The characterization of Masson pine(Pinus massoniana) MYB TFs are reported, including the analysis of MYB TFs expression in seedlings under controlled conditions and two different phosphate(Pi) deficient treatments. By searching for conserved MYB motifs in full transcriptomic RNA sequencing data for P. massoniana, 59 sequences were identified as MYB TFs. Conserved domainstructures and comparative functional and phylogenetic relationships of these MYB TFs with those in Arabidopsis were assessed using various bioinformatics tools. Based on microarray analysis, P. massoniana MYB genes exhibited different expression patterns under the two Pi deficiency conditions. Genes encoding MYB TFs that showed increased expression under critical Pi deficiency were identified, and some MYBs were differentially expressed only under conditions of severe Pi starvation. These results are useful for the functional characterization of MYB TFs that may be involved in the response to Pi deficiency and play divergent roles in plants.
