The equilibrium solubility of Rebaudioside A(Reb A)FormⅡin binary mixtures of methanol/ethanol and ethyl acetate was quantitatively determined within the temperature range of 283.15—328.15 K at ambient pressure.The ...The equilibrium solubility of Rebaudioside A(Reb A)FormⅡin binary mixtures of methanol/ethanol and ethyl acetate was quantitatively determined within the temperature range of 283.15—328.15 K at ambient pressure.The experimental findings indicate a positive correlation between the solubility of Reb A(FormⅡ)and both the temperature and the methanol/ethanol content in the solvent system.To describe the solubility data,six distinct models were employed:the modified Apelblat equation,theλh model,the combined nearly ideal binary solvent/Redlich—Kister(CNIBS/R—K)model,the van't HoffJouyban-Acree(VJA)model,the Apelblat-Jouyban-Acree(AJA)model,and the non-random two-liquid(NRTL)model.The combined nearly ideal binary solvent/Redlich—Kister model exhibited the most precise fit for solubility in methanol+ethyl acetate mixtures,reflected by an average relative deviation(ARD)of 0.0011 and a root mean square deviation(RMSD)of 12×10^(-7).Conversely,for ethanol+ethyl acetate mixtures,the modified Apelblat equation provided a superior correlation(ARD=0.0014,RMSD=4×10^(-7)).Furthermore,thermodynamic parameters associated with the dissolution of Reb A(FormⅡ),including enthalpy,entropy,and the Gibbs energy change,were inferred from the data.The findings underscore that the dissolution process is predominantly endothermic across the solvent systems examined.Notably,the entropy changes appear to have a significant influence on the Gibbs free energy associated with the dissolution of Reb A(FormⅡ),suggesting that entropic factors may play a pivotal role in the studied systems.展开更多
Plant anatomy is patterned early during leaf development which suggests studying the spatial–temporal transcriptomes of primordia will help identify critical regulative and functional genes.We successfully isolated t...Plant anatomy is patterned early during leaf development which suggests studying the spatial–temporal transcriptomes of primordia will help identify critical regulative and functional genes.We successfully isolated the leaf primordia tissues from the C3grass rice and the C4grass foxtail millet by laser capture microdissection(LCM)and studied the gene expression throughout leaf developmental stages.Our data analysis uncovered the conserved expression patterns of certain gene clusters both in rice and foxtail millet during leaf development.We revealed genes and transcription factors involved in vein formation,stomatal development,and suberin accumulation.We identified 79 candidate genes associated with functional regulation of C4anatomy formation.Screening phenotype of the candidate genes revealed that knock-out of a putative polar auxin transport related gene NAL1 resulted significantly reduced veinal space in rice leaf.Our present work provides a foundation for future analyses of genes with novel functions in grasses and their role in leaf development,in particular the role in leaves with a contrasting C3vs.C4biosynthetic pathway.展开更多
The development and maturation of the CRISPR/Cas genome editing system provides a valuable tool for plant functional genomics and genetic improvement.Currently available genome-editing tools have a limited number of t...The development and maturation of the CRISPR/Cas genome editing system provides a valuable tool for plant functional genomics and genetic improvement.Currently available genome-editing tools have a limited number of targets,restricting their application in genetic research.In this study,we developed a novel CRISPR/Cas9 plant ultra-multiplex genome editing system consisting of two template vectors,eight donor vectors,four destination vectors,and one primer-design software package.By combining the advantages of Golden Gate cloning to assemble multiple repetitive fragments and Gateway recombination to assemble large fragments and by changing the structure of the amplicons used to assemble sg RNA expression cassettes,the plant ultra-multiplex genome editing system can assemble a single binary vector targeting more than 40 genomic loci.A rice knockout vector containing 49 sg RNA expression cassettes was assembled and a high co-editing efficiency was observed.This plant ultra-multiplex genome editing system advances synthetic biology and plant genetic engineering.展开更多
OSAHS(Obstructive Sleep Apnea Hypopnea Syndrome)is a respiratory disease mainly characterized by limited and repeated pauses of breathing in sleep.Currently,the optimal treatment is to apply CPAP(Continuous Positive A...OSAHS(Obstructive Sleep Apnea Hypopnea Syndrome)is a respiratory disease mainly characterized by limited and repeated pauses of breathing in sleep.Currently,the optimal treatment is to apply CPAP(Continuous Positive Airway Pressure)ventilation on the upper airway of the patient through a household respiratory machine.However,if the ventilator mask is designed improperly,it might cause the residue and repeated inhalation of CO2,which will exert an adverse impact on the therapeutic effect.Present research numerically analyzed the CO2 transportation inside a commercial ventilator mask(Mirage SoftGel,ResMed,Australia)based on the reconstructed 3D numerical model of a volunteer's face and performed the improved design of the ventilator mask in terms of the CO2 residual concentration below the nostrils.The fluid dynamic analyses showed that at the end time of expiratory,the CO2 residual concentration below the nostrils is close to 4%.To improve the therapeutic effect,we changed the position of the exhaust holes and found that by moving the exhaust holes to the bottom of the ventilator mask,the CO2 residual concentration below the nostrils would be reduced to no more than 1%.This study established a near physiological computational model and provided a new method for the individualized design of the commercial ventilator mask.展开更多
Nonfullerene organic solar cells(OSCs)have achieved breakthrough with pushing the efficiency exceeding 17%.While this shed light on OSC commercialization,high-performance flexible OSCs should be pursued through soluti...Nonfullerene organic solar cells(OSCs)have achieved breakthrough with pushing the efficiency exceeding 17%.While this shed light on OSC commercialization,high-performance flexible OSCs should be pursued through solution manufacturing.Herein,we report a solution-processed flexible OSC based on a transparent conducting PEDOT:PSS anode doped with trifluoromethanesulfonic acid(CF3SO3H).Through a low-concentration and low-temperature CF3SO3H doping,the conducting polymer anodes exhibited a main sheet resistance of 35Ωsq−1(minimum value:32Ωsq−1),a raised work function(≈5.0 eV),a superior wettability,and a high electrical stability.The high work function minimized the energy level mismatch among the anodes,hole-transporting layers and electron-donors of the active layers,thereby leading to an enhanced carrier extraction.The solution-processed flexible OSCs yielded a record-high efficiency of 16.41%(maximum value:16.61%).Besides,the flexible OSCs afforded the 1000 cyclic bending tests at the radius of 1.5 mm and the long-time thermal treatments at 85°C,demonstrating a high flexibility and a good thermal stability.展开更多
Metal–organic frameworks(MOFs) packed in the column have been a promising candidate as the stationary phase for high performance liquid chromatography(HPLC). However, the direct packing of irregular MOF powder could ...Metal–organic frameworks(MOFs) packed in the column have been a promising candidate as the stationary phase for high performance liquid chromatography(HPLC). However, the direct packing of irregular MOF powder could raise some problems like high back pressure and low column efficiency in the HPLC separation. In this work, UiO-66 capable of separating xylenes was supported effectively on the surface of the monodisperse spherical silica microspheres by one-pot method. The hybridization of Ui O-66 and silica microspheres(termed UiO-66@SiO2 shell–core composite) was prepared by stirring the suspension of the precursors of Ui O-66 and\\COOH terminated silica in the N,N-dimethylformamide with heating. The shell–core composite material UiO66@SiO2 was characterized by SEM, TEM, PXRD and FTIR. Then, it was used as a packing material for the chromatographic separation of xylene isomers. Xylene isomers including o-xylene, m-xylene and p-xylene were efficiently separated on the column with high resolution and good reproducibility. Moreover, the Ui O-66@SiO2 shell–core composites packed column still remained reverse shape selectivity as Ui O-66 possessed, and the retention of xylenes was probably ascribed to the hydrophobic effect between analytes and the aromatic rings of the Ui O-66 shell. The Ui O-66@SiO2 shell–core composites obtained in this study have some potential for the separation of structural isomers in HPLC.展开更多
Lithium-sulfur(Li-S) batteries are one of the most promising rechargeable storage devices due to the high theoretical energy density.However,the low areal sulfur loading impedes their commercial development.Herein,a 3...Lithium-sulfur(Li-S) batteries are one of the most promising rechargeable storage devices due to the high theoretical energy density.However,the low areal sulfur loading impedes their commercial development.Herein,a 3 D free-standing sulfur cathode scaffold is rationally designed and fabricated by coaxially coating polar Ti_3 C_2 T_x flakes on sulfur-impregnated carbon cloth(Ti_3 C_2 T_x@S/CC) to achieve high loading and high energy density Li-S batteries,in which,the flexible CC substrate with highly porous structure can accommodate large amounts of sulfur and ensure fast electron transfer,while the outer-coated Ti_3 C_2 T_x can serve as a polar and conductive protective layer to further promote the conductivity of the whole electrode,achieve physical blocking and chemical anchoring of lithium-polysulfides as well as catalyze their conversion.Due to these advantages,at a sulfur loading of 4 mg cm^(-2),Li-S cells with Ti_3 C_2 T_x@S/CC cathodes can deliver outstanding cycling stability(746.1 mAh g^(-1) after 200 cycles at1 C),superb rate performance(866.8 mAh g^(-1) up to 2 C) and a high specific energy density(564.2 Wh kg^(-1) after 100 cycles at 0.5 C).More significantly,they also show the commercial potential that can compete with current lithium-ion batteries due to the high areal capacity of 6.7 mAh cm^(-2) at the increased loading of 8 mg cm^(-2).展开更多
Rosa rugosa Thunb.is recognized as both medicine and edible in China.The article investigated the antitumor activity of rose flavonoids.Water-extracted rose flavonoids(RFW)and ethanol-extracted rose flavonoids(RFE)wer...Rosa rugosa Thunb.is recognized as both medicine and edible in China.The article investigated the antitumor activity of rose flavonoids.Water-extracted rose flavonoids(RFW)and ethanol-extracted rose flavonoids(RFE)were achieved by extracting with distilled water and 70%ethanol,respectively.The effects of the two extracts on proliferation inhibition,apoptosis inducement and metastasis prevention of human HepG2 hepatocellular carcinoma cell lines were tested,via optical/fluorescence microscopy,MTT detection,Transwell assay,flow cytometry and Western blot,etc.The results indicated that rose flavonoids at low concentration(10-40μg/mL)had a better inhibitory effect on migration and invasion of HepG2 cells in a dose-dependent manner,while rose flavonoids at high concentration(80-160μg/mL)could induce apoptosis of HepG2 cells by up-regulating the expression of pro-apoptotic proteins p53 and Bax,and down-regulating the expression of anti-apoptotic proteins Bcl-2,leading to the functioning of caspase-3 and caspase-9.The effect of RFE at the same concentration was significantly better than that of RFW.Conclusion,this study found that rose flavonoids had a certain inhibitory effect on proliferation and metastasis of human liver cancer cells HepG2,indicating the application of rose flavonoids in preventing and treating of liver cancer.展开更多
Chloroplasts are the center of plant life activities including photosynthesis,growth and development,and abiotic stress response.Chloroplast development and biogenesis in rice have been studied in detail,but how does ...Chloroplasts are the center of plant life activities including photosynthesis,growth and development,and abiotic stress response.Chloroplast development and biogenesis in rice have been studied in detail,but how does abiotic stress affect chloroplasts is less studied.We obtained an albino mutant,alm1,whose chlorophyll content was greatly decreased.Transmission electron microscopy showed that chloroplast development in alm1 was blocked,especially in thylakoid-like structures,which could not form normally.The ALM1 gene encodes a chloroplast-localized superoxide dismutase.Full-length ALM1 successfully restored the non-albino phenotype,and in knockout lines,the albino phenotype reappeared.The ALM1gene is expressed mainly in young leaves.alm1 plants died as a consequence of excessive reactive oxygen accumulation after the third-leaf stage.A series of biochemical assays verified that ALM1 interacted with the OsTrxz protein,which is one of the components of plastid-encoded RNA polymerase (PEP) complexes.A western blot experiment indicated that ALM1 played an important role in stabilizing OsTrxz in rice.An overexpression test of ALM1 revealed that ALM1 can increase drought resistance by removing excess reactive oxygen in rice seedlings.This study suggests that ALM1 not only participates in rice chloroplast biogenesis,but also increases rice stress resistance by scavenging excess reactive oxygen.展开更多
The operational cloud-motion tracking technique fails to retrieve atmospheric motion vectors (AMVs) in areas lacking cloud; and while water vapor shown in water vapor imagery can be used, the heights assigned to the...The operational cloud-motion tracking technique fails to retrieve atmospheric motion vectors (AMVs) in areas lacking cloud; and while water vapor shown in water vapor imagery can be used, the heights assigned to the retrieved AMVs are mostly in the upper troposphere. As the noise-equivalent temperature difference (NEdT) performance of FY-2E split win- dow (10.3-11.5 μm, 11.6-12.8 μm) channels has been improved, the weak signals representing the spatial texture of water vapor and aerosols in cloud-free areas can be strengthened with algorithms based on the difference principle, and applied in calculating AMVs in the lower troposphere. This paper is a preliminary summary for this purpose, in which the principles and algorithm schemes for the temporal difference, split window difference and second-order difference (SD) methods are introduced. Results from simulation and cases experiments are reported in order to verify and evaluate the methods, based on comparison among retrievals and the "truth". The results show that all three algorithms, though not perfect in some cases, generally work well. Moreover, the SD method appears to be the best in suppressing the surface temperature influence and clarifying the spatial texture of water vapor and aerosols. The accuracy with respect to NCEP 800 hPa reanalysis data was found to be acceptable, as compared with the accuracy of the cloud motion vectors.展开更多
Electrode material based on a novel core–shell structure consisting of NiCoS(NCS) solid fiber core and Mn S(MS) sheet shell(NCS@MS) in situ grown on carbon cloth(CC) has been successfully prepared by a simple...Electrode material based on a novel core–shell structure consisting of NiCoS(NCS) solid fiber core and Mn S(MS) sheet shell(NCS@MS) in situ grown on carbon cloth(CC) has been successfully prepared by a simple sulfurization-assisted hydrothermal method for high performance supercapacitor. The synthesized NiCoS@Mn S/CC electrode shows high capacitance of 1908.3 F gat a current density of 0.5 A gwhich is higher than those of NiCoSand Mn S at the same current density. A flexible all-solid-state asymmetric supercapacitor(ASC) is constructed by using NiCoS@Mn S/CC as positive electrode, active carbon/CC as negative electrode and KOH/poly(vinyl alcohol)(PVA) as electrolyte. The optimized ASC shows a maximum energy density of 23.3 Wh kgat 1 A g, a maximum power density of about7.5 kw kgat 10 A gand remarkable cycling stability. After 9000 cycles, the ASC still exhibited67.8% retention rate and largely unchanged charge/discharge curves. The excellent electrochemical properties are resulted from the novel core–shell structure of the NiCoS@Mn S/CC electrode, which possesses both high surface area for Faraday redox reaction and superior kinetics of charge transport. The NiCoS@Mn S/CC electrode shows a promising potential for energy storage applications in the future.展开更多
MXenes are well known for their potential application in supercapacitors due to their high-rate intercalation pseudocapacitance and long cyclability.However,the reported low capacity of pristine MXenes hinders their p...MXenes are well known for their potential application in supercapacitors due to their high-rate intercalation pseudocapacitance and long cyclability.However,the reported low capacity of pristine MXenes hinders their practical application in lithium-ion batteries.In this work,a robust strategy is developed to control the functional groups of Nb_2 CT_x MXene.The capacity of pristine Nb_2 CT_x MXene can be significantly increased by Li~+ intercalation and surface modification.The specific capacity of the treated Nb_2 CT_x is up to 448 mAh g^(-1) at 0.05 A g^(-1),and at a large current density of 2 A g^(-1) remains a high reversible capacity retention rate of 75% after an ultra-long cycle of 2000 cycles.These values exceed most of the reported pristine MXenes(including the most studied Ti_3 C_2 T_x) and carbon-based materials.It demonstrates that this strategy has great help to improve the electrochemical performance of pristine MXene,and the results enhance the promise of MXenes in the application of lithium-ion batteries.展开更多
Metal sulfides are promising anode materials for sodium ion batteries(SIBs)due to their high theoretical specific capacity and abundant source.Nevertheless,significant challenges,including large volume change,sluggish...Metal sulfides are promising anode materials for sodium ion batteries(SIBs)due to their high theoretical specific capacity and abundant source.Nevertheless,significant challenges,including large volume change,sluggish Na^(+)transport kinetics and polysulfides intermediates,have greatly affect their long cycle stability.Unfortunately,the majority of current studies only focus on the first two aspects,but lack of sufficient attention and insights into the effect of polysulfides intermediates.Here,a porous of CoS_(x)(P-CoS_(x))electrode material is fabricated as an example to investigate the influence of polysulfides on its cycling performance.The results show that polysulfides cause a slight loss of reversible capacity during the battery cycling,while the failure of the battery is due to its significant fluctuations in reversible capacity after extensive cycles.Detailed analyses demonstrate that the intense fluctuation in capacity originates from the faster growth of dendrites caused by the reaction of sodium polysulfides with sodium foil and/or the reaction of elemental sulfur with sodium foil to penetrate the separator,resulting in a local short circuit.To suppress these undesirable side reaction,N,S co-doped porous carbon tubes(N,S-PC)rich in C–S and C–N bonds have been added to adsorb polysulfides and alleviate their reaction with sodium foil.As a result,the capacity of the P-CoS_(x) electrode with N,S-PC(P-CoS_(x)/N,S-PC)remains stable without significant fluctuations for 1000 cycles,which is much better than that of the pure P-CoS_(x) electrode(intense fluctuation in capacity after 320 cycles).Our work offers insights into the crucial influence of polysulfides on the cycle performance of the P-CoS_(x) anode and provides a feasible strategy to prolong the cycle life of metal sulfide anode for SIBs.展开更多
Mn doping is deemed as a promising strategy to improve the electrochemical performance of the a-Ni(OH)_(2)battery-type supercapacitor electrode.However,the internal structure evolution,the pathways and the dynamics of...Mn doping is deemed as a promising strategy to improve the electrochemical performance of the a-Ni(OH)_(2)battery-type supercapacitor electrode.However,the internal structure evolution,the pathways and the dynamics of the proton/intercalated anion migration,as well as the functioning mechanism of Mn dopant to stabilize the layered structure during cycles remain unclear.Here,we unveil that irreversible oxidization of Mn^(3+)at the initial CV cycles,which will remain as Mn^(4+)in the NiO_(2)slabs after the first oxidization to effectively suppress the phase transformation fromα-Ni(OH)_(2)/γ-NiOOH toβ-Ni(OH)_(2)/β-NiOOH and further maintain the structural integrity of electrode.With a synergistic combination of theoretical calculations and various structural probes including XRD and^(2)H MAS solid state NMR,we decode the structure evolution and dynamics in the initial CV(cyclic voltammetry)cycles,including the absorption/desorption of hydrogen containing species,migration of intercalated anions/water molecules and the change of interlayer space.This present work elucidates a close relationship between doping chemistry and structural reliability,paving a novel way of reengineering supercapacitor electrode materials.展开更多
Inhomogeneous Pb/Sn elemental distribution and the resulted phase segregation in mixed Pb-Sn halide perovskites would result in energy disorder(band structure and phase distribution disorder),which greatly limits thei...Inhomogeneous Pb/Sn elemental distribution and the resulted phase segregation in mixed Pb-Sn halide perovskites would result in energy disorder(band structure and phase distribution disorder),which greatly limits their photovoltaic performance.Here,Pb S quantum dot has been synthesized and demonstrated as seeds for modulation crystallization dynamics of the mixed Pb-Sn inorganic perovskites,allowing an enhanced film quality and significantly suppressing phase segregation.With this additive power conversion efficiency of 8%and 6%is obtained under irradiation of full sunlight in planar and mesoporous structured solar cells in combination with CsPb_(0.5) Sn_(0.5)I_(2)Br inorganic perovskite,respectively.Our finding reveals exploring the actual Pb/Sn atoms location in perovskite structure and its influence on developing efficient and stable low-bandgap perovskite solar cells.展开更多
For the first time,WO_(2.72) nanowires were in-situ grown on carbon cloth by a simple solvothermal reaction.The nanowire WO_(2.72)/carbon cloth(NW WO_(2.72)/CC) electrode showed good electrochemical performance with s...For the first time,WO_(2.72) nanowires were in-situ grown on carbon cloth by a simple solvothermal reaction.The nanowire WO_(2.72)/carbon cloth(NW WO_(2.72)/CC) electrode showed good electrochemical performance with specific capacitance(C_s) reaching up to 398 F g^(-1) at a current density of 2 A g^(-1).The capacitance of 240 F g^(-1) was retained at a high current density of 16 A g^(-1).To further evaluate the energy storage performance,flexible asymmetric supercapacitors(FASC_s) were fabricated using the activated carbon/carbon cloth(AC/CC) as negative electrode and NW WO_(2.72)/CC as positive electrode,respectively.The FASC_s delivered a high energy density of 28 Wh kg^(-1) at a power density of 745 W kg^(-1) and 13 Wh kg^(-1) even at a high power density of 22.5 k W kg^(-1).More impressively,81% of the specific capacitance of the FASC_s was retained after 10,000 cycles,indicating excellent cycle stability.This work indicates the NW WO_(2.72)/CC holds a great potential for application in energy storage devices.展开更多
Exogenous humus can change the content and migration activity of cadmium(Cd)in soil.Humic acid(HA)is an important soluble humus component in soil.In order to explore the relationship between cadmium pollution mechanis...Exogenous humus can change the content and migration activity of cadmium(Cd)in soil.Humic acid(HA)is an important soluble humus component in soil.In order to explore the relationship between cadmium pollution mechanism and ecological environment of humic acid in reclaimed soil,the characteristics of humic acid adsorbing cadmium in alkaline conditions were studied.This study employed reclaimed soil from the Huainan mining area,China.The adsorption and desorption characteristics as well as influence mechanisms on the heavy metal cadmium(Cd)were explored under the influence of HA.The results show that:(1)When Cd concentration was low(0.2–10 mg/L),HA had little effect on Cd adsorption and desorption in reclaimed soil.When the Cd concentration was high(15–80 mg/L),HA had a great influence on the adsorption and desorption of Cd in reclaimed soil.The addition of HA can inhibit the adsorption of Cd by reclaimed soil and effectively improve the desorption capacity of Cd by reclaimed soil.(2)The kinetic curves of Cd adsorption and desorption of reclaimed soil with added HA show that both processes(adsorption and desorption)include two stages:rapid reaction and slow reaction.The adsorption of Cd by reclaimed soil under the influence of HA was 18.18%lower than that of normal reclaimed soil,and the increase of Cd desorption was 50.29%.(3)The factors affecting the adsorption and desorption of Cd in the soil were analyzed with gray theory,and their importance can be ordered as follows:Cd concentration>HA concentration>pH>temperature.Considering the influence of HA,a multi-factor coupling function model of adsorption and desorption of Cd in soil is established.This model provides theoretical guidance for the scientific prediction and evaluation of Cd environmental pollution risks in soil and will be useful for developing a new solution for engineering remediation of high concentration Cd contaminated soil.展开更多
Hierarchical porous TiOnanopills were synthesized using a titanium metal-organic framework MIL-125(Ti) as precursor. The as-synthesized TiOnanopills owned a large specific surface area of 102 m/g and unique porous s...Hierarchical porous TiOnanopills were synthesized using a titanium metal-organic framework MIL-125(Ti) as precursor. The as-synthesized TiOnanopills owned a large specific surface area of 102 m/g and unique porous structure. Furthermore, the obtained TiOnanopills were applied as anode materials for Na-ion batteries for the first time. The as-synthesized TiOnanopills achieved a high discharge capacity of 196.4 m Ah/g at a current density of 0.1 A/g. A discharge capacity of 115.9 m Ah/g was obtained at a high current density of 0.5 A/g and the capacity retention was remained as high as 90% even after 3000 cycles. The excellent electrochemical performance can be attributed to its unique hierarchical porous feature.展开更多
基金supported by the National Key Research and Development Program of China(2021YFC2103800)the National Natural Science Foundation of China(U21A20301)the Research Funds of Institute of Zhejiang University-Quzhou(IZQ2022RCZX004 and IZQ2021RCZX015)。
文摘The equilibrium solubility of Rebaudioside A(Reb A)FormⅡin binary mixtures of methanol/ethanol and ethyl acetate was quantitatively determined within the temperature range of 283.15—328.15 K at ambient pressure.The experimental findings indicate a positive correlation between the solubility of Reb A(FormⅡ)and both the temperature and the methanol/ethanol content in the solvent system.To describe the solubility data,six distinct models were employed:the modified Apelblat equation,theλh model,the combined nearly ideal binary solvent/Redlich—Kister(CNIBS/R—K)model,the van't HoffJouyban-Acree(VJA)model,the Apelblat-Jouyban-Acree(AJA)model,and the non-random two-liquid(NRTL)model.The combined nearly ideal binary solvent/Redlich—Kister model exhibited the most precise fit for solubility in methanol+ethyl acetate mixtures,reflected by an average relative deviation(ARD)of 0.0011 and a root mean square deviation(RMSD)of 12×10^(-7).Conversely,for ethanol+ethyl acetate mixtures,the modified Apelblat equation provided a superior correlation(ARD=0.0014,RMSD=4×10^(-7)).Furthermore,thermodynamic parameters associated with the dissolution of Reb A(FormⅡ),including enthalpy,entropy,and the Gibbs energy change,were inferred from the data.The findings underscore that the dissolution process is predominantly endothermic across the solvent systems examined.Notably,the entropy changes appear to have a significant influence on the Gibbs free energy associated with the dissolution of Reb A(FormⅡ),suggesting that entropic factors may play a pivotal role in the studied systems.
基金supported by the National Key Research and Development Program of China(NKRDP)(2022YFF1001700)the Agricultural Science and Technology Innovation Program(2020YFE0202300)the National Natural Science Foundation of China(31871313)。
文摘Plant anatomy is patterned early during leaf development which suggests studying the spatial–temporal transcriptomes of primordia will help identify critical regulative and functional genes.We successfully isolated the leaf primordia tissues from the C3grass rice and the C4grass foxtail millet by laser capture microdissection(LCM)and studied the gene expression throughout leaf developmental stages.Our data analysis uncovered the conserved expression patterns of certain gene clusters both in rice and foxtail millet during leaf development.We revealed genes and transcription factors involved in vein formation,stomatal development,and suberin accumulation.We identified 79 candidate genes associated with functional regulation of C4anatomy formation.Screening phenotype of the candidate genes revealed that knock-out of a putative polar auxin transport related gene NAL1 resulted significantly reduced veinal space in rice leaf.Our present work provides a foundation for future analyses of genes with novel functions in grasses and their role in leaf development,in particular the role in leaves with a contrasting C3vs.C4biosynthetic pathway.
基金supported by the National Natural Science Foundation of China(32001532 and 31860411)the National Key Research and Development Program of China,(2022YFF1000020)+1 种基金Hunan Seed Industry Innovation Project(2021NK1012)the Yunnan Tobacco Company Project(2020530000241009)。
文摘The development and maturation of the CRISPR/Cas genome editing system provides a valuable tool for plant functional genomics and genetic improvement.Currently available genome-editing tools have a limited number of targets,restricting their application in genetic research.In this study,we developed a novel CRISPR/Cas9 plant ultra-multiplex genome editing system consisting of two template vectors,eight donor vectors,four destination vectors,and one primer-design software package.By combining the advantages of Golden Gate cloning to assemble multiple repetitive fragments and Gateway recombination to assemble large fragments and by changing the structure of the amplicons used to assemble sg RNA expression cassettes,the plant ultra-multiplex genome editing system can assemble a single binary vector targeting more than 40 genomic loci.A rice knockout vector containing 49 sg RNA expression cassettes was assembled and a high co-editing efficiency was observed.This plant ultra-multiplex genome editing system advances synthetic biology and plant genetic engineering.
基金financially supported by the National Natural Science Foundation of China(21722609 and 21878260)the Zhejiang Provincial Natural Science Foundation of China(LR170B060001).
基金We acknowledge the National Natural Science Foundation of China for supporting the project via the grant number 11472062 and 11002034.
文摘OSAHS(Obstructive Sleep Apnea Hypopnea Syndrome)is a respiratory disease mainly characterized by limited and repeated pauses of breathing in sleep.Currently,the optimal treatment is to apply CPAP(Continuous Positive Airway Pressure)ventilation on the upper airway of the patient through a household respiratory machine.However,if the ventilator mask is designed improperly,it might cause the residue and repeated inhalation of CO2,which will exert an adverse impact on the therapeutic effect.Present research numerically analyzed the CO2 transportation inside a commercial ventilator mask(Mirage SoftGel,ResMed,Australia)based on the reconstructed 3D numerical model of a volunteer's face and performed the improved design of the ventilator mask in terms of the CO2 residual concentration below the nostrils.The fluid dynamic analyses showed that at the end time of expiratory,the CO2 residual concentration below the nostrils is close to 4%.To improve the therapeutic effect,we changed the position of the exhaust holes and found that by moving the exhaust holes to the bottom of the ventilator mask,the CO2 residual concentration below the nostrils would be reduced to no more than 1%.This study established a near physiological computational model and provided a new method for the individualized design of the commercial ventilator mask.
基金The authors acknowledge funding from the National Natural Science Foundation of China(61974150 and 51773213)Key Research Program of Frontier Sciences,CAS(QYZDB-SSW-JSC047)+1 种基金the Fundamental Research Funds for the Central Universities,the CAS-EU S&T cooperation partner program(174433KYSB20150013)the Natural Science Foundation of Ningbo(2018A610135).
文摘Nonfullerene organic solar cells(OSCs)have achieved breakthrough with pushing the efficiency exceeding 17%.While this shed light on OSC commercialization,high-performance flexible OSCs should be pursued through solution manufacturing.Herein,we report a solution-processed flexible OSC based on a transparent conducting PEDOT:PSS anode doped with trifluoromethanesulfonic acid(CF3SO3H).Through a low-concentration and low-temperature CF3SO3H doping,the conducting polymer anodes exhibited a main sheet resistance of 35Ωsq−1(minimum value:32Ωsq−1),a raised work function(≈5.0 eV),a superior wettability,and a high electrical stability.The high work function minimized the energy level mismatch among the anodes,hole-transporting layers and electron-donors of the active layers,thereby leading to an enhanced carrier extraction.The solution-processed flexible OSCs yielded a record-high efficiency of 16.41%(maximum value:16.61%).Besides,the flexible OSCs afforded the 1000 cyclic bending tests at the radius of 1.5 mm and the long-time thermal treatments at 85°C,demonstrating a high flexibility and a good thermal stability.
基金Supported by the National Natural Science Foundation of China(21722609,21776240)Zhejiang Provincial Natural Science Foundation of China(LR17B060001)
文摘Metal–organic frameworks(MOFs) packed in the column have been a promising candidate as the stationary phase for high performance liquid chromatography(HPLC). However, the direct packing of irregular MOF powder could raise some problems like high back pressure and low column efficiency in the HPLC separation. In this work, UiO-66 capable of separating xylenes was supported effectively on the surface of the monodisperse spherical silica microspheres by one-pot method. The hybridization of Ui O-66 and silica microspheres(termed UiO-66@SiO2 shell–core composite) was prepared by stirring the suspension of the precursors of Ui O-66 and\\COOH terminated silica in the N,N-dimethylformamide with heating. The shell–core composite material UiO66@SiO2 was characterized by SEM, TEM, PXRD and FTIR. Then, it was used as a packing material for the chromatographic separation of xylene isomers. Xylene isomers including o-xylene, m-xylene and p-xylene were efficiently separated on the column with high resolution and good reproducibility. Moreover, the Ui O-66@SiO2 shell–core composites packed column still remained reverse shape selectivity as Ui O-66 possessed, and the retention of xylenes was probably ascribed to the hydrophobic effect between analytes and the aromatic rings of the Ui O-66 shell. The Ui O-66@SiO2 shell–core composites obtained in this study have some potential for the separation of structural isomers in HPLC.
基金supported by the National Natural Science Foundation of China (51772069)。
文摘Lithium-sulfur(Li-S) batteries are one of the most promising rechargeable storage devices due to the high theoretical energy density.However,the low areal sulfur loading impedes their commercial development.Herein,a 3 D free-standing sulfur cathode scaffold is rationally designed and fabricated by coaxially coating polar Ti_3 C_2 T_x flakes on sulfur-impregnated carbon cloth(Ti_3 C_2 T_x@S/CC) to achieve high loading and high energy density Li-S batteries,in which,the flexible CC substrate with highly porous structure can accommodate large amounts of sulfur and ensure fast electron transfer,while the outer-coated Ti_3 C_2 T_x can serve as a polar and conductive protective layer to further promote the conductivity of the whole electrode,achieve physical blocking and chemical anchoring of lithium-polysulfides as well as catalyze their conversion.Due to these advantages,at a sulfur loading of 4 mg cm^(-2),Li-S cells with Ti_3 C_2 T_x@S/CC cathodes can deliver outstanding cycling stability(746.1 mAh g^(-1) after 200 cycles at1 C),superb rate performance(866.8 mAh g^(-1) up to 2 C) and a high specific energy density(564.2 Wh kg^(-1) after 100 cycles at 0.5 C).More significantly,they also show the commercial potential that can compete with current lithium-ion batteries due to the high areal capacity of 6.7 mAh cm^(-2) at the increased loading of 8 mg cm^(-2).
基金supported by the natural science foundation of Shandong province ZR2017BH053the youth doctor cooperation foundation of Qilu University of Technology(Shandong Academy of Sciences)2017BSH2017。
文摘Rosa rugosa Thunb.is recognized as both medicine and edible in China.The article investigated the antitumor activity of rose flavonoids.Water-extracted rose flavonoids(RFW)and ethanol-extracted rose flavonoids(RFE)were achieved by extracting with distilled water and 70%ethanol,respectively.The effects of the two extracts on proliferation inhibition,apoptosis inducement and metastasis prevention of human HepG2 hepatocellular carcinoma cell lines were tested,via optical/fluorescence microscopy,MTT detection,Transwell assay,flow cytometry and Western blot,etc.The results indicated that rose flavonoids at low concentration(10-40μg/mL)had a better inhibitory effect on migration and invasion of HepG2 cells in a dose-dependent manner,while rose flavonoids at high concentration(80-160μg/mL)could induce apoptosis of HepG2 cells by up-regulating the expression of pro-apoptotic proteins p53 and Bax,and down-regulating the expression of anti-apoptotic proteins Bcl-2,leading to the functioning of caspase-3 and caspase-9.The effect of RFE at the same concentration was significantly better than that of RFW.Conclusion,this study found that rose flavonoids had a certain inhibitory effect on proliferation and metastasis of human liver cancer cells HepG2,indicating the application of rose flavonoids in preventing and treating of liver cancer.
基金supported by Key Laboratory of Joint CAAS/ IRRI Laboratory for Photosynthetic Enhancement, Biotechnology Research Institute/National Key Facility for Genetic Resources and Gene Improvementsupported by the National Key Research and Development Program of China (2020YFA0907600)+1 种基金the Agricultural Science and Technology Innovation Program (CAAS-ZDXT2019003)Fundamental Research Funds for Central Non-profit Scientific Institution。
文摘Chloroplasts are the center of plant life activities including photosynthesis,growth and development,and abiotic stress response.Chloroplast development and biogenesis in rice have been studied in detail,but how does abiotic stress affect chloroplasts is less studied.We obtained an albino mutant,alm1,whose chlorophyll content was greatly decreased.Transmission electron microscopy showed that chloroplast development in alm1 was blocked,especially in thylakoid-like structures,which could not form normally.The ALM1 gene encodes a chloroplast-localized superoxide dismutase.Full-length ALM1 successfully restored the non-albino phenotype,and in knockout lines,the albino phenotype reappeared.The ALM1gene is expressed mainly in young leaves.alm1 plants died as a consequence of excessive reactive oxygen accumulation after the third-leaf stage.A series of biochemical assays verified that ALM1 interacted with the OsTrxz protein,which is one of the components of plastid-encoded RNA polymerase (PEP) complexes.A western blot experiment indicated that ALM1 played an important role in stabilizing OsTrxz in rice.An overexpression test of ALM1 revealed that ALM1 can increase drought resistance by removing excess reactive oxygen in rice seedlings.This study suggests that ALM1 not only participates in rice chloroplast biogenesis,but also increases rice stress resistance by scavenging excess reactive oxygen.
基金supported by the National Natural Science Foundation of China(Grant Nos.41175035 and 40475018)the National Basic Research Program of China(Grant No.2009CB421502)a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘The operational cloud-motion tracking technique fails to retrieve atmospheric motion vectors (AMVs) in areas lacking cloud; and while water vapor shown in water vapor imagery can be used, the heights assigned to the retrieved AMVs are mostly in the upper troposphere. As the noise-equivalent temperature difference (NEdT) performance of FY-2E split win- dow (10.3-11.5 μm, 11.6-12.8 μm) channels has been improved, the weak signals representing the spatial texture of water vapor and aerosols in cloud-free areas can be strengthened with algorithms based on the difference principle, and applied in calculating AMVs in the lower troposphere. This paper is a preliminary summary for this purpose, in which the principles and algorithm schemes for the temporal difference, split window difference and second-order difference (SD) methods are introduced. Results from simulation and cases experiments are reported in order to verify and evaluate the methods, based on comparison among retrievals and the "truth". The results show that all three algorithms, though not perfect in some cases, generally work well. Moreover, the SD method appears to be the best in suppressing the surface temperature influence and clarifying the spatial texture of water vapor and aerosols. The accuracy with respect to NCEP 800 hPa reanalysis data was found to be acceptable, as compared with the accuracy of the cloud motion vectors.
基金supported by the Grant-in-Aid for Scientific Research (KAKENHI) program, Japan (C, Grant Number 15K05597)Takahashi Industrial and Economic Research Foundation (Takahashi Grant Number 06-003-154)
文摘Electrode material based on a novel core–shell structure consisting of NiCoS(NCS) solid fiber core and Mn S(MS) sheet shell(NCS@MS) in situ grown on carbon cloth(CC) has been successfully prepared by a simple sulfurization-assisted hydrothermal method for high performance supercapacitor. The synthesized NiCoS@Mn S/CC electrode shows high capacitance of 1908.3 F gat a current density of 0.5 A gwhich is higher than those of NiCoSand Mn S at the same current density. A flexible all-solid-state asymmetric supercapacitor(ASC) is constructed by using NiCoS@Mn S/CC as positive electrode, active carbon/CC as negative electrode and KOH/poly(vinyl alcohol)(PVA) as electrolyte. The optimized ASC shows a maximum energy density of 23.3 Wh kgat 1 A g, a maximum power density of about7.5 kw kgat 10 A gand remarkable cycling stability. After 9000 cycles, the ASC still exhibited67.8% retention rate and largely unchanged charge/discharge curves. The excellent electrochemical properties are resulted from the novel core–shell structure of the NiCoS@Mn S/CC electrode, which possesses both high surface area for Faraday redox reaction and superior kinetics of charge transport. The NiCoS@Mn S/CC electrode shows a promising potential for energy storage applications in the future.
基金Project supported by the National Science Foundation of China (No.51772070 and 51772069)。
文摘MXenes are well known for their potential application in supercapacitors due to their high-rate intercalation pseudocapacitance and long cyclability.However,the reported low capacity of pristine MXenes hinders their practical application in lithium-ion batteries.In this work,a robust strategy is developed to control the functional groups of Nb_2 CT_x MXene.The capacity of pristine Nb_2 CT_x MXene can be significantly increased by Li~+ intercalation and surface modification.The specific capacity of the treated Nb_2 CT_x is up to 448 mAh g^(-1) at 0.05 A g^(-1),and at a large current density of 2 A g^(-1) remains a high reversible capacity retention rate of 75% after an ultra-long cycle of 2000 cycles.These values exceed most of the reported pristine MXenes(including the most studied Ti_3 C_2 T_x) and carbon-based materials.It demonstrates that this strategy has great help to improve the electrochemical performance of pristine MXene,and the results enhance the promise of MXenes in the application of lithium-ion batteries.
基金supported by the National Natural Science Foundation of China(Grant Nos.22075064,21673065)。
文摘Metal sulfides are promising anode materials for sodium ion batteries(SIBs)due to their high theoretical specific capacity and abundant source.Nevertheless,significant challenges,including large volume change,sluggish Na^(+)transport kinetics and polysulfides intermediates,have greatly affect their long cycle stability.Unfortunately,the majority of current studies only focus on the first two aspects,but lack of sufficient attention and insights into the effect of polysulfides intermediates.Here,a porous of CoS_(x)(P-CoS_(x))electrode material is fabricated as an example to investigate the influence of polysulfides on its cycling performance.The results show that polysulfides cause a slight loss of reversible capacity during the battery cycling,while the failure of the battery is due to its significant fluctuations in reversible capacity after extensive cycles.Detailed analyses demonstrate that the intense fluctuation in capacity originates from the faster growth of dendrites caused by the reaction of sodium polysulfides with sodium foil and/or the reaction of elemental sulfur with sodium foil to penetrate the separator,resulting in a local short circuit.To suppress these undesirable side reaction,N,S co-doped porous carbon tubes(N,S-PC)rich in C–S and C–N bonds have been added to adsorb polysulfides and alleviate their reaction with sodium foil.As a result,the capacity of the P-CoS_(x) electrode with N,S-PC(P-CoS_(x)/N,S-PC)remains stable without significant fluctuations for 1000 cycles,which is much better than that of the pure P-CoS_(x) electrode(intense fluctuation in capacity after 320 cycles).Our work offers insights into the crucial influence of polysulfides on the cycle performance of the P-CoS_(x) anode and provides a feasible strategy to prolong the cycle life of metal sulfide anode for SIBs.
基金supported by the National Natural Science Foundation of China(Grant No.21673065,No.21403045,No.21611130177)。
文摘Mn doping is deemed as a promising strategy to improve the electrochemical performance of the a-Ni(OH)_(2)battery-type supercapacitor electrode.However,the internal structure evolution,the pathways and the dynamics of the proton/intercalated anion migration,as well as the functioning mechanism of Mn dopant to stabilize the layered structure during cycles remain unclear.Here,we unveil that irreversible oxidization of Mn^(3+)at the initial CV cycles,which will remain as Mn^(4+)in the NiO_(2)slabs after the first oxidization to effectively suppress the phase transformation fromα-Ni(OH)_(2)/γ-NiOOH toβ-Ni(OH)_(2)/β-NiOOH and further maintain the structural integrity of electrode.With a synergistic combination of theoretical calculations and various structural probes including XRD and^(2)H MAS solid state NMR,we decode the structure evolution and dynamics in the initial CV(cyclic voltammetry)cycles,including the absorption/desorption of hydrogen containing species,migration of intercalated anions/water molecules and the change of interlayer space.This present work elucidates a close relationship between doping chemistry and structural reliability,paving a novel way of reengineering supercapacitor electrode materials.
基金Financial support from the National Key Research and Development Program of China (2019YFE0101300, 2018YFB1502900)the National Natural Science Foundation of China (No. 21975088)+1 种基金the National Natural Science Foundation of China Major International (Regional) Joint Research Project (No. 51961165106)the double first-class research funding of China-EU Institute for Clean and Renewable Energy (3011187029)。
文摘Inhomogeneous Pb/Sn elemental distribution and the resulted phase segregation in mixed Pb-Sn halide perovskites would result in energy disorder(band structure and phase distribution disorder),which greatly limits their photovoltaic performance.Here,Pb S quantum dot has been synthesized and demonstrated as seeds for modulation crystallization dynamics of the mixed Pb-Sn inorganic perovskites,allowing an enhanced film quality and significantly suppressing phase segregation.With this additive power conversion efficiency of 8%and 6%is obtained under irradiation of full sunlight in planar and mesoporous structured solar cells in combination with CsPb_(0.5) Sn_(0.5)I_(2)Br inorganic perovskite,respectively.Our finding reveals exploring the actual Pb/Sn atoms location in perovskite structure and its influence on developing efficient and stable low-bandgap perovskite solar cells.
基金supported by the Grant-in-Aid for Scientific Research (KAKENHI) Program,Japan (C,Grant Number 15K05597)Takahashi Industrial and Research Center for Solar Light Energy Conversion,Kyushu Institute of Technology
文摘For the first time,WO_(2.72) nanowires were in-situ grown on carbon cloth by a simple solvothermal reaction.The nanowire WO_(2.72)/carbon cloth(NW WO_(2.72)/CC) electrode showed good electrochemical performance with specific capacitance(C_s) reaching up to 398 F g^(-1) at a current density of 2 A g^(-1).The capacitance of 240 F g^(-1) was retained at a high current density of 16 A g^(-1).To further evaluate the energy storage performance,flexible asymmetric supercapacitors(FASC_s) were fabricated using the activated carbon/carbon cloth(AC/CC) as negative electrode and NW WO_(2.72)/CC as positive electrode,respectively.The FASC_s delivered a high energy density of 28 Wh kg^(-1) at a power density of 745 W kg^(-1) and 13 Wh kg^(-1) even at a high power density of 22.5 k W kg^(-1).More impressively,81% of the specific capacitance of the FASC_s was retained after 10,000 cycles,indicating excellent cycle stability.This work indicates the NW WO_(2.72)/CC holds a great potential for application in energy storage devices.
基金This research was supported by the National Natural Science Foundation of China(No.51904014)the Natural Science Research Project of University in Anhui Province(No.KJ2018A0072)the Postdoctoral Foundation of Anhui Province(No.2019B337).
文摘Exogenous humus can change the content and migration activity of cadmium(Cd)in soil.Humic acid(HA)is an important soluble humus component in soil.In order to explore the relationship between cadmium pollution mechanism and ecological environment of humic acid in reclaimed soil,the characteristics of humic acid adsorbing cadmium in alkaline conditions were studied.This study employed reclaimed soil from the Huainan mining area,China.The adsorption and desorption characteristics as well as influence mechanisms on the heavy metal cadmium(Cd)were explored under the influence of HA.The results show that:(1)When Cd concentration was low(0.2–10 mg/L),HA had little effect on Cd adsorption and desorption in reclaimed soil.When the Cd concentration was high(15–80 mg/L),HA had a great influence on the adsorption and desorption of Cd in reclaimed soil.The addition of HA can inhibit the adsorption of Cd by reclaimed soil and effectively improve the desorption capacity of Cd by reclaimed soil.(2)The kinetic curves of Cd adsorption and desorption of reclaimed soil with added HA show that both processes(adsorption and desorption)include two stages:rapid reaction and slow reaction.The adsorption of Cd by reclaimed soil under the influence of HA was 18.18%lower than that of normal reclaimed soil,and the increase of Cd desorption was 50.29%.(3)The factors affecting the adsorption and desorption of Cd in the soil were analyzed with gray theory,and their importance can be ordered as follows:Cd concentration>HA concentration>pH>temperature.Considering the influence of HA,a multi-factor coupling function model of adsorption and desorption of Cd in soil is established.This model provides theoretical guidance for the scientific prediction and evaluation of Cd environmental pollution risks in soil and will be useful for developing a new solution for engineering remediation of high concentration Cd contaminated soil.
基金supported by JSPS KAKENHI Grant Number15K00597Takahashi Industrial and Economic Research Foundation Japan Grant Number 06-003-154
文摘Hierarchical porous TiOnanopills were synthesized using a titanium metal-organic framework MIL-125(Ti) as precursor. The as-synthesized TiOnanopills owned a large specific surface area of 102 m/g and unique porous structure. Furthermore, the obtained TiOnanopills were applied as anode materials for Na-ion batteries for the first time. The as-synthesized TiOnanopills achieved a high discharge capacity of 196.4 m Ah/g at a current density of 0.1 A/g. A discharge capacity of 115.9 m Ah/g was obtained at a high current density of 0.5 A/g and the capacity retention was remained as high as 90% even after 3000 cycles. The excellent electrochemical performance can be attributed to its unique hierarchical porous feature.