Schwertmannite, a common iron-derived mineral, is known for its high efficiency in adsorbing As from water and reducing the mobility and availability of As in soils. However,few studies have examined the critical peri...Schwertmannite, a common iron-derived mineral, is known for its high efficiency in adsorbing As from water and reducing the mobility and availability of As in soils. However,few studies have examined the critical period for the effectiveness of schwertmannite in hindering As uptake by rice plants, particularly its impact on the uptake and transport of As across different growth stages of rice. In this study, hydroponic experiments were performed to explore the absorption and translocation of As(500 μg/L As(Ⅲ) or As(Ⅴ)), when combined with schwertmannite, in rice during all growth stages. The results showed that As concentration in roots, stems and leaves increased with rice growth, while the addition of schwertmannite reduced the As concentration in all parts of rice, compared to the control without schwertmannite. Besides, schwertmannite application mitigated the harmful impact of As on rice yield, and reduced As levels in grains by 66 %-90 % compared to treatments with only As(Ⅲ) or As(Ⅴ). The heading stage is identified as a critical period for applying schwertmannite to reduce As uptake in rice. Specifically, during the heading stages,the plants uptake 85 %-91 % of the As contents in the absence of schwertmannite. However,adding schwertmannite retained about 84 %-90 % of As content, significantly reducing its absorption by rice plants at this stage. Therefore, maintaining As adsorption by schwertmannite up to the heading stage is beneficial to effectively reduce As uptake in rice and lower As concentration in rice grains.展开更多
Due to the features and wide range of potential applications,cellulose ionogels are the subject of extensive research.Green celluloses have been employed as a three-dimensional skeleton network to restrict the ionic l...Due to the features and wide range of potential applications,cellulose ionogels are the subject of extensive research.Green celluloses have been employed as a three-dimensional skeleton network to restrict the ionic liquids(ILs)toward advanced ion-conductive ionogels.Diversiform cellulose ionogels with desirable perfor-mances,via physical/chemical reactions between cellulose and ILs,have been harvested,which have the po-tential to emerge as a bright star in the field of flexible electronics,such as sensors,electrolyte materials as power sources,and thermoelectric devices.Herein,a review regarding cellulose ionogels in terms of fundamental types of cellulose,formation strategies and mechanism,and principal properties is presented.Next,the diverse application prospects of cellulose ionogels in flexible electronics have been summarized.More importantly,the future challenges and advancing directions to be explored for cellulose ionogels are discussed.展开更多
A plastic may degrade in response to a trigger.The kinetics of degradation have long been characterized by the loss of weight and strength over time.These methods of gross characterization,however,are misleading when ...A plastic may degrade in response to a trigger.The kinetics of degradation have long been characterized by the loss of weight and strength over time.These methods of gross characterization,however,are misleading when plastic degrades heterogeneously.Here,we study heterogeneous degradation in an extreme form:the growth of a crack under the combined action of chemistry and mechanics.An applied load opens the crack,exposes the crack front to chemical attack,and causes the crack to outrun gross degradation.We studied the crack growth in polylactic acid(PLA),a polyester in which ester bonds break by hydrolysis.We cut a crack in a PLA film using scissors,tore it using an apparatus,and recorded the crack growth using a camera through a microscope.In our testing range,the crack velocity was insensitive to load but was sensitive to humidity and pH.These findings will aid the development of degradable plastics for healthcare and sustainability.展开更多
Aiming at the low accuracy problem of power system short-term load forecasting by traditional methods, a back-propagation artificial neural network （BP-ANN） based method for short-term load forecasting is presented ...Aiming at the low accuracy problem of power system short-term load forecasting by traditional methods, a back-propagation artificial neural network （BP-ANN） based method for short-term load forecasting is presented in this paper. The forecast points are related to prophase adjacent data as well as the periodical long-term historical load data. Then the short-term load forecasting model of Shanxi Power Grid （China） based on BP-ANN method and correlation analysis is established. The simulation model matches well with practical power system load, indicating the BP-ANN method is simple and with higher precision and practicality.展开更多
Wet wood is an abnormal phenomenon in growing trees,which adversely affects growth,subsequent wood processing and economic values of wood products.In this study,the influences of factors such as clones,afforestation m...Wet wood is an abnormal phenomenon in growing trees,which adversely affects growth,subsequent wood processing and economic values of wood products.In this study,the influences of factors such as clones,afforestation methods,site conditions and climate conditions on the characteristics of poplar wetwood were studied through field investigations in 27 clones from 48 sample plots in 28 counties.Results showed that the incidences of wetwood were almost 100%in all plots.Ratios of wetwood area among the48 plots differed from 15.1 to 90.2%.Wetwood area ratios,moisture contents and pH differed significantly between the 27 clones.Wetwood area ratios of the clones ranged from18.7 to 62.3%.Ratios of wetwood areas were positively correlated with wet wood moisture content and pH,tree age,and negatively correlated with pH of sap wood.The repeatability of wet wood area ratios was 0.52,moderately controlled by genetics.Wetwood moisture content and pH were highly controlled by genetics,indicated by the repeatability of 0.91 and 0.89,respectively.There were significant differences in wetwood area ratios,moisture content and pH between different site conditions,afforestation methods,and geographical regions.Sloping land had the lowest wetwood area ratios and moisture content among four types of sites.Afforestation by direct seeding and rooted cuttings had the lowest wetwood area ratios and moisture content,respectively.In the three geographical regions,the Yellow River Basin had the lowest wetwood values of all three factors.展开更多
Dental resin composites(DRCs)are popular materials for repairing caries or dental defect,requiring excellent properties to cope with the complex oral environment.Filler/resin interface interaction has a significant im...Dental resin composites(DRCs)are popular materials for repairing caries or dental defect,requiring excellent properties to cope with the complex oral environment.Filler/resin interface interaction has a significant impact on the physicochemical/biological properties and service life of DRCs.展开更多
In this study,natural bamboo fiber was prepared combining chemical pretreatment with mechanical disc refining,opening,and carding.An orthogonal experiment was designed based on four factors and three levels;thereafter...In this study,natural bamboo fiber was prepared combining chemical pretreatment with mechanical disc refining,opening,and carding.An orthogonal experiment was designed based on four factors and three levels;thereafter,the manufacturing process was optimized.The length,diameter,tensile strength,and elastic modulus of the bamboo fiber were determined,and the crystallinity and morphology of the fiber were analyzed using X-ray diffraction(XRD)and scanning electron microscopy(SEM).The results showed that the optimum parameters for the chemical pretreatment were a cooking temperature of 130℃,heating time of 2 h,NaOH dosage of 2%,and Na2SO3 dosage of 10%.The cooking yield of bamboo chips was 89.5%,and the carding yield of natural bamboo fiber was 43.0% under the optimum conditions.The length,diameter,tensile strength,and elastic modulus of the obtained fiber were 36.71 mm,0.285 mm,407 MPa,and 27.7 GPa,respectively.XRD analysis and SEM observations showed that the technology used in this study can produce bright and compact natural bamboo fibers with high crystallinity.展开更多
Quantum light sources serve as one of the key elements in quantum photonic technologies. Such sources made from semiconductor material, e.g., quantum dots (QDs), are particularly appealing because of their great poten...Quantum light sources serve as one of the key elements in quantum photonic technologies. Such sources made from semiconductor material, e.g., quantum dots (QDs), are particularly appealing because of their great potential of scalability enabled by the modern planar nanofabrication technologies. So far, non-classic light sources based on semiconductor QDs are currently outperforming their counterparts using nonlinear optical process, for instance, parametric down conversion and four-wave mixing. To fully exploring the potential of semiconductor QDs, it is highly desirable to integrate QDs with a variety of photonic nanostructures for better device performance due to the improved light-matter interaction. Among different designs, the photonic nanostructures exhibiting broad operation spectral range is particularly interesting to overcome the QD spectral inhomogeneity and exciton fine structure splitting for the generations of single-photon and entangled photon pair respectively. In this review, we focus on recent progress on high-performance semiconductor quantum light sources that is achieved by integrating single QDs with a variety of broadband photonic nanostructures i.e. waveguide, lens and low-Q cavity.展开更多
Xanthomonas spp. cause severe bacterial diseases. However, effective strategies for prevention and management of these diseases are scarce. Thus, it is necessary to improve the efficiency of control of diseases caused...Xanthomonas spp. cause severe bacterial diseases. However, effective strategies for prevention and management of these diseases are scarce. Thus, it is necessary to improve the efficiency of control of diseases caused by Xanthomonas. In this study, Xanthomonas oryzae pv. oryzae(Xoo), which causes rice bacterial leaf blight, has been studied as a representative. A transposon insertion library of Xoo, comprising approximately 200,000 individual insertion mutants, was generated. Transposon sequencing data indicated that the mariner C9 transposase mapped at 35.7–36.4% of all potential insertion sites, revealing 491 essential genes required for the growth of Xoo in rich media. The results show that, compared to the functions of essential genes of other bacteria, the functions of some essential genes of Xoo are unknown, 25 genes might be dangerous for the Xanthomonas group, and 3 are specific to Xanthomonas. High-priority candidates for developing broad-spectrum, Xanthomonas-specific, and environment-friendly bactericides were identified in this study. In addition, this study revealed the possible targets of dioctyldiethylenetriamine using surface plasmon resonance(SPR) in combination with high performance liquid chromatography–mass spectrometry(HPLC–MS). The study also provided references for the research of some certain bactericides with unknown anti-bacterial mode of action. In conclusion, this study urged a better understanding of Xanthomonas,provided meaningful data for the management of bacterial leaf blight, and disclosed selected targets of a novel bactericide.展开更多
The response patterns of microbial functional genes involved in biogeochemical cycles to cadaver decay is a central topic of recent environmental sciences.However,the response mechanisms and pathways of the functional...The response patterns of microbial functional genes involved in biogeochemical cycles to cadaver decay is a central topic of recent environmental sciences.However,the response mechanisms and pathways of the functional genes associated with the carbon(C)and nitrogen(N)cycling to cadaveric substances such as cadaverine and putrescine remain unclear.This study explored the variation of functional genes associated with C fixation,C degradation and N cycling and their influencing factors under cadaverine,putrescine and mixed treatments.Our results showed only putrescine significantly increased the alpha diversity of C fixation genes,while reducing the alpha diversity of N cycling genes in sediment.For the C cycling,the mixed treatment significantly decreased the total abundance of reductive acetyl-CoA pathway genes(i.e.,acsB and acsE)and lig gene linked to lignin degradation in water,while only significantly increasing the hydroxypropionate-hydroxybutylate cycle(i.e.,accA)gene abundance in sediment.For the N cycling,mixed treatment significantly decreased the abundance of the nitrification(i.e.,amoB),denitrification(i.e.,nirS3)genes in water and the assimilation pathway gene(i.e.,gdhA)in sediment.Environmental factors(i.e.,total carbon and total nitrogen)were all negatively associated with the genes of C and N cycling.Therefore,cadaverine and putrescine exposure may inhibit the pathway in C fixation and N cycling,while promoting C degradation.These findings can offer some new insight for the management of amine pollution caused by animal cadavers.展开更多
Alloying with Se is proved to be feasible to suppress the lattice thermal conductivity(κL)of tellurium by introducing multidimensional lattice defects.However,extra ionization impurity centers induced by Se alloying ...Alloying with Se is proved to be feasible to suppress the lattice thermal conductivity(κL)of tellurium by introducing multidimensional lattice defects.However,extra ionization impurity centers induced by Se alloying are harmful to the electric transport properties of the matrix.In this paper,we propose that the incorporation of Ag could successfully compensate the lost carrier mobility(μH)due to Se alloying through the regulation of microstructure,resulting in the higher power factor(PF)than that of samples without Ag.After composition optimization,theκLdecreased from 1.29 W m^(-1)K^(-1) of Te_(0.99)Sb_(0.01) to 1.05 W m^(-1)K^(-1) of Te_(0.94)Ag_(0.02)Se_(0.03)Sb_(0.01) at 350 K,while the PF remained unchanged or even slightly increased.Benefit from the synergistic effect of carrier mobility compensation and phonon scattering,a maximum z T of 0.91 at 573 K and an average z T of 0.57(between 298 and 573 K)are achieved in Te_(0.94)Ag_(0.02)Se_(0.03)Sb_(0.01).This work presents a new strategy for decoupling the thermal and electric parameters of Te-based thermoelectric materials.展开更多
Polycrystalline BAsx(x=0.80-1.10)compounds with different boron-to-arsenic elemental molar ratios were synthesized by a high-pressure and high-temperature sintering method.Compared with other ambient-pressure synthesi...Polycrystalline BAsx(x=0.80-1.10)compounds with different boron-to-arsenic elemental molar ratios were synthesized by a high-pressure and high-temperature sintering method.Compared with other ambient-pressure synthesis methods,high pressure can significantly promote the reaction speed as well as the reaction yield.As the content of arsenic increases from x=0.91 to 1.10,the thermal conductivity of BAsx gradually increases from 53 to 65 W·m-1·K-1.Furthermore,the temperature dependence of thermal conductivities of these samples reveals an Umklapp scattering due to the increasing phonon population.This work provides a highly efficient method for polycrystalline BAs synthesis.展开更多
In response to the requirements for large-scale device access and ultra-reliable and low-latency communication in the power internet of things,unmanned aerial vehicle-assisted multi-access edge computing can be used t...In response to the requirements for large-scale device access and ultra-reliable and low-latency communication in the power internet of things,unmanned aerial vehicle-assisted multi-access edge computing can be used to realize flexible access to power services and update large amounts of information in a timely manner.By considering factors such as machine communication traffic,MAC competition access,and information freshness,this paper develops a cross-layer computing framework in which the peak Age of Information(Ao I)provides a statistical delay boundary in the finite blocklength regime.We also propose a deep machine learning-based multi-access edge computing offloading algorithm.First,a traffic arrival model is established in which the time interval follows the Beta distribution,and then a business service model is proposed based on the carrier sense multiple access with collision avoidance algorithm.The peak Ao I boundary performance of multiple access is evaluated according to stochastic network calculus theory.Finally,an unmanned aerial vehicle-assisted multilevel offloading model with cache is designed,in which the peak Ao I violation probability and energy consumption provide the optimization goals.The optimal offloading strategy is obtained using deep reinforcement learning.Compared with baseline schemes based on non-cooperative game theory with stochastic learning automata and random edge unloading,the proposed algorithm improves the overall performance by approximately 3.52%and 20.73%,respectively,and provides superior deterministic offloading performance by using the peak Ao I boundary.展开更多
Hydrogels emerge as a promising electrode material for scalp electroencephalogram monitoring,which stands as a pivotal technique in neuroscience,enabling real-time monitoring of brain activity.However,conventional hyd...Hydrogels emerge as a promising electrode material for scalp electroencephalogram monitoring,which stands as a pivotal technique in neuroscience,enabling real-time monitoring of brain activity.However,conventional hydrogel-enabled electrodes suffer from low scalp compliance,high scalpelectrode impedance,and inferior interfacial stability.Here,we propose an injectable eutectogelenabled electrode for high-quality,long-term scalp electroencephalogram monitoring.This gelatinbased eutectogel exhibits temperature-controlled reversible phase transitions,enabling rapid in-situ gelation on the scalp and forming a robust self-adhesive interface.It demonstrates exceptional mechanical durability(1000 cycles at 100%strain),robust adhesion(0.7 N cm^(-1)on human epidermis and 1.7 N cm^(-1)on Ag/AgCl electrode),and outstanding anti-drying properties(negligible water loss after 7 days).Additionally,the eutectogel shows superior healing properties,antibacterial properties,and recyclability.Furthermore,it exhibits remarkably low scalp-electrode contact impedance(<20 kΩat 16 Hz).The eutectogel is injected on the human scalp with dense hair for high-fidelity electroencephalogram recording,enabling long-term monitoring.Its practical applications include monitoring visual evoked potentials,steady-state visual evoked potentials,somatosensory evoked potentials,slow vertex response,auditory brainstem response,multi-channel cognitive electroencephalogram during various daily activities,and event-related potentials P300 signals.The eutectogel-enabled electrode provides a versatile and reliable solution for long-term electroencephalogram monitoring in diverse clinical and research settings.展开更多
Soft electronics have seen extensive development due to their lightness,outstanding mechanical flexibility,and biocompatibility,which make them ideal for a variety of applications,including health monitoring,human-mac...Soft electronics have seen extensive development due to their lightness,outstanding mechanical flexibility,and biocompatibility,which make them ideal for a variety of applications,including health monitoring,human-machine interfaces,and advanced augmented reality/virtual reality communications[1,2].Ionic liquid(IL)-based conductive hydrogels are typically made up of a polymer network swollen with IL,which are organic salts in a liquid state at or near room temperature,rather than traditional inorganic/organic salt electrolyte solutions[3-5].These hydrogels leverage the unique properties of IL,such as high ionic conductivity,nonvolatility,and thermal stability,to create a flexible conductive material suitable for various applications in soft electronics,such as actuators,wearable sensors,and stretchable energy generation/storage devices[6-8].展开更多
基金supported by the National Natural Science Foundation of China(Nos.22336003 and 42177222)the National Key Research and Development Program of China(No.2023YFC3707600).
文摘Schwertmannite, a common iron-derived mineral, is known for its high efficiency in adsorbing As from water and reducing the mobility and availability of As in soils. However,few studies have examined the critical period for the effectiveness of schwertmannite in hindering As uptake by rice plants, particularly its impact on the uptake and transport of As across different growth stages of rice. In this study, hydroponic experiments were performed to explore the absorption and translocation of As(500 μg/L As(Ⅲ) or As(Ⅴ)), when combined with schwertmannite, in rice during all growth stages. The results showed that As concentration in roots, stems and leaves increased with rice growth, while the addition of schwertmannite reduced the As concentration in all parts of rice, compared to the control without schwertmannite. Besides, schwertmannite application mitigated the harmful impact of As on rice yield, and reduced As levels in grains by 66 %-90 % compared to treatments with only As(Ⅲ) or As(Ⅴ). The heading stage is identified as a critical period for applying schwertmannite to reduce As uptake in rice. Specifically, during the heading stages,the plants uptake 85 %-91 % of the As contents in the absence of schwertmannite. However,adding schwertmannite retained about 84 %-90 % of As content, significantly reducing its absorption by rice plants at this stage. Therefore, maintaining As adsorption by schwertmannite up to the heading stage is beneficial to effectively reduce As uptake in rice and lower As concentration in rice grains.
基金supported by the National Natural Science Foundation of China(No.32271976,32371978)scientific and technological innovation funding of Fujian Agriculture and Forestry University(KFb22087,KFB23145).
文摘Due to the features and wide range of potential applications,cellulose ionogels are the subject of extensive research.Green celluloses have been employed as a three-dimensional skeleton network to restrict the ionic liquids(ILs)toward advanced ion-conductive ionogels.Diversiform cellulose ionogels with desirable perfor-mances,via physical/chemical reactions between cellulose and ILs,have been harvested,which have the po-tential to emerge as a bright star in the field of flexible electronics,such as sensors,electrolyte materials as power sources,and thermoelectric devices.Herein,a review regarding cellulose ionogels in terms of fundamental types of cellulose,formation strategies and mechanism,and principal properties is presented.Next,the diverse application prospects of cellulose ionogels in flexible electronics have been summarized.More importantly,the future challenges and advancing directions to be explored for cellulose ionogels are discussed.
基金The work at Harvard University,USA was supported by National Science Foundation(NSF)Materials Research Science and Engineering Centers(MRSEC)(DMR-2011754)X.Yang was a visiting student at Harvard University supported by the China Scholarship Council.J.Steck acknowledges support from the NSF Graduate Research Fellowship(DGE1745303).
文摘A plastic may degrade in response to a trigger.The kinetics of degradation have long been characterized by the loss of weight and strength over time.These methods of gross characterization,however,are misleading when plastic degrades heterogeneously.Here,we study heterogeneous degradation in an extreme form:the growth of a crack under the combined action of chemistry and mechanics.An applied load opens the crack,exposes the crack front to chemical attack,and causes the crack to outrun gross degradation.We studied the crack growth in polylactic acid(PLA),a polyester in which ester bonds break by hydrolysis.We cut a crack in a PLA film using scissors,tore it using an apparatus,and recorded the crack growth using a camera through a microscope.In our testing range,the crack velocity was insensitive to load but was sensitive to humidity and pH.These findings will aid the development of degradable plastics for healthcare and sustainability.
文摘Aiming at the low accuracy problem of power system short-term load forecasting by traditional methods, a back-propagation artificial neural network （BP-ANN） based method for short-term load forecasting is presented in this paper. The forecast points are related to prophase adjacent data as well as the periodical long-term historical load data. Then the short-term load forecasting model of Shanxi Power Grid （China） based on BP-ANN method and correlation analysis is established. The simulation model matches well with practical power system load, indicating the BP-ANN method is simple and with higher precision and practicality.
基金funded by the Hubei Provincial Natural Science Foundation of China (2021CFB446)the National Natural Science Foundation of China (31570665)+1 种基金the National Key Research and Development Program of China (2021YFD2201202)the Fundamental Research Funds for the Central Universities (2662020YLPY017)。
文摘Wet wood is an abnormal phenomenon in growing trees,which adversely affects growth,subsequent wood processing and economic values of wood products.In this study,the influences of factors such as clones,afforestation methods,site conditions and climate conditions on the characteristics of poplar wetwood were studied through field investigations in 27 clones from 48 sample plots in 28 counties.Results showed that the incidences of wetwood were almost 100%in all plots.Ratios of wetwood area among the48 plots differed from 15.1 to 90.2%.Wetwood area ratios,moisture contents and pH differed significantly between the 27 clones.Wetwood area ratios of the clones ranged from18.7 to 62.3%.Ratios of wetwood areas were positively correlated with wet wood moisture content and pH,tree age,and negatively correlated with pH of sap wood.The repeatability of wet wood area ratios was 0.52,moderately controlled by genetics.Wetwood moisture content and pH were highly controlled by genetics,indicated by the repeatability of 0.91 and 0.89,respectively.There were significant differences in wetwood area ratios,moisture content and pH between different site conditions,afforestation methods,and geographical regions.Sloping land had the lowest wetwood area ratios and moisture content among four types of sites.Afforestation by direct seeding and rooted cuttings had the lowest wetwood area ratios and moisture content,respectively.In the three geographical regions,the Yellow River Basin had the lowest wetwood values of all three factors.
基金the support from the National Natural Science Foundation of China(Grant nos.81921002,82201115)China Postdoctoral Science Foundation(no.2021M702166)the Innovative Research Team of High-level Local Universities in Shanghai,Oral and Maxillofacial Regeneration and Functional Restoration。
文摘Dental resin composites(DRCs)are popular materials for repairing caries or dental defect,requiring excellent properties to cope with the complex oral environment.Filler/resin interface interaction has a significant impact on the physicochemical/biological properties and service life of DRCs.
基金financially supported by the National Key R&D Program of China(2017YFD0600802).
文摘In this study,natural bamboo fiber was prepared combining chemical pretreatment with mechanical disc refining,opening,and carding.An orthogonal experiment was designed based on four factors and three levels;thereafter,the manufacturing process was optimized.The length,diameter,tensile strength,and elastic modulus of the bamboo fiber were determined,and the crystallinity and morphology of the fiber were analyzed using X-ray diffraction(XRD)and scanning electron microscopy(SEM).The results showed that the optimum parameters for the chemical pretreatment were a cooking temperature of 130℃,heating time of 2 h,NaOH dosage of 2%,and Na2SO3 dosage of 10%.The cooking yield of bamboo chips was 89.5%,and the carding yield of natural bamboo fiber was 43.0% under the optimum conditions.The length,diameter,tensile strength,and elastic modulus of the obtained fiber were 36.71 mm,0.285 mm,407 MPa,and 27.7 GPa,respectively.XRD analysis and SEM observations showed that the technology used in this study can produce bright and compact natural bamboo fibers with high crystallinity.
基金supported by National Key R&D Program of China(No.2018YFA0306100)the National Natural Science Foundations of China(Nos.11874437,11704424)+2 种基金the Natural Science Foundation of Guangdong Province(Nos.2018B030311027,2017A030310004,2016A030310216)Guangzhou Science and Technology Project(No.201805010004)the National Natural Science Foundation of China(No.60123456)
文摘Quantum light sources serve as one of the key elements in quantum photonic technologies. Such sources made from semiconductor material, e.g., quantum dots (QDs), are particularly appealing because of their great potential of scalability enabled by the modern planar nanofabrication technologies. So far, non-classic light sources based on semiconductor QDs are currently outperforming their counterparts using nonlinear optical process, for instance, parametric down conversion and four-wave mixing. To fully exploring the potential of semiconductor QDs, it is highly desirable to integrate QDs with a variety of photonic nanostructures for better device performance due to the improved light-matter interaction. Among different designs, the photonic nanostructures exhibiting broad operation spectral range is particularly interesting to overcome the QD spectral inhomogeneity and exciton fine structure splitting for the generations of single-photon and entangled photon pair respectively. In this review, we focus on recent progress on high-performance semiconductor quantum light sources that is achieved by integrating single QDs with a variety of broadband photonic nanostructures i.e. waveguide, lens and low-Q cavity.
基金This study was supported by the National Natural Science Foundation of China(32272587 and 32202342)the Programs for the Scientific Research Activities of Academic and Technical Leaders of Anhui Province,China(2020D251)+3 种基金the Development Fund for Talent Personnel of Anhui Agricultural University,China(rc342006)the University Synergy Innovation Program of Anhui Province,China(GXXT-2021-059)the Key Project of the Natural Science Foundation of Anhui Provincial Department of Education,China(2023AH040129)Anhui Province Agricultural Eco-Environmental Protection and Quality Safety Industry Technology System,China。
文摘Xanthomonas spp. cause severe bacterial diseases. However, effective strategies for prevention and management of these diseases are scarce. Thus, it is necessary to improve the efficiency of control of diseases caused by Xanthomonas. In this study, Xanthomonas oryzae pv. oryzae(Xoo), which causes rice bacterial leaf blight, has been studied as a representative. A transposon insertion library of Xoo, comprising approximately 200,000 individual insertion mutants, was generated. Transposon sequencing data indicated that the mariner C9 transposase mapped at 35.7–36.4% of all potential insertion sites, revealing 491 essential genes required for the growth of Xoo in rich media. The results show that, compared to the functions of essential genes of other bacteria, the functions of some essential genes of Xoo are unknown, 25 genes might be dangerous for the Xanthomonas group, and 3 are specific to Xanthomonas. High-priority candidates for developing broad-spectrum, Xanthomonas-specific, and environment-friendly bactericides were identified in this study. In addition, this study revealed the possible targets of dioctyldiethylenetriamine using surface plasmon resonance(SPR) in combination with high performance liquid chromatography–mass spectrometry(HPLC–MS). The study also provided references for the research of some certain bactericides with unknown anti-bacterial mode of action. In conclusion, this study urged a better understanding of Xanthomonas,provided meaningful data for the management of bacterial leaf blight, and disclosed selected targets of a novel bactericide.
基金supported by the National Natural Science Foundation of China(No.42007026)the Medical Innovation and Development Project of Lanzhou University(No.lzuyxcx-2022-172)。
文摘The response patterns of microbial functional genes involved in biogeochemical cycles to cadaver decay is a central topic of recent environmental sciences.However,the response mechanisms and pathways of the functional genes associated with the carbon(C)and nitrogen(N)cycling to cadaveric substances such as cadaverine and putrescine remain unclear.This study explored the variation of functional genes associated with C fixation,C degradation and N cycling and their influencing factors under cadaverine,putrescine and mixed treatments.Our results showed only putrescine significantly increased the alpha diversity of C fixation genes,while reducing the alpha diversity of N cycling genes in sediment.For the C cycling,the mixed treatment significantly decreased the total abundance of reductive acetyl-CoA pathway genes(i.e.,acsB and acsE)and lig gene linked to lignin degradation in water,while only significantly increasing the hydroxypropionate-hydroxybutylate cycle(i.e.,accA)gene abundance in sediment.For the N cycling,mixed treatment significantly decreased the abundance of the nitrification(i.e.,amoB),denitrification(i.e.,nirS3)genes in water and the assimilation pathway gene(i.e.,gdhA)in sediment.Environmental factors(i.e.,total carbon and total nitrogen)were all negatively associated with the genes of C and N cycling.Therefore,cadaverine and putrescine exposure may inhibit the pathway in C fixation and N cycling,while promoting C degradation.These findings can offer some new insight for the management of amine pollution caused by animal cadavers.
基金financially supported by the National Natural Science Foundation of China (No. 51871240)。
文摘Alloying with Se is proved to be feasible to suppress the lattice thermal conductivity(κL)of tellurium by introducing multidimensional lattice defects.However,extra ionization impurity centers induced by Se alloying are harmful to the electric transport properties of the matrix.In this paper,we propose that the incorporation of Ag could successfully compensate the lost carrier mobility(μH)due to Se alloying through the regulation of microstructure,resulting in the higher power factor(PF)than that of samples without Ag.After composition optimization,theκLdecreased from 1.29 W m^(-1)K^(-1) of Te_(0.99)Sb_(0.01) to 1.05 W m^(-1)K^(-1) of Te_(0.94)Ag_(0.02)Se_(0.03)Sb_(0.01) at 350 K,while the PF remained unchanged or even slightly increased.Benefit from the synergistic effect of carrier mobility compensation and phonon scattering,a maximum z T of 0.91 at 573 K and an average z T of 0.57(between 298 and 573 K)are achieved in Te_(0.94)Ag_(0.02)Se_(0.03)Sb_(0.01).This work presents a new strategy for decoupling the thermal and electric parameters of Te-based thermoelectric materials.
基金Supported by the National Key R&D Program of China(Grant Nos.2018YFE0103200 and 2018YFA0305700)the National Natural Science Foundation of China(Grant Nos.51772324,11934017,11921004,and 11574378)the Chinese Academy of Sciences(Grant Nos.QYZDB–SSW–SLH013 and GJHZ1773)。
文摘Polycrystalline BAsx(x=0.80-1.10)compounds with different boron-to-arsenic elemental molar ratios were synthesized by a high-pressure and high-temperature sintering method.Compared with other ambient-pressure synthesis methods,high pressure can significantly promote the reaction speed as well as the reaction yield.As the content of arsenic increases from x=0.91 to 1.10,the thermal conductivity of BAsx gradually increases from 53 to 65 W·m-1·K-1.Furthermore,the temperature dependence of thermal conductivities of these samples reveals an Umklapp scattering due to the increasing phonon population.This work provides a highly efficient method for polycrystalline BAs synthesis.
基金supported in part by the National Natural Science Foundation of China(Nos.61601182)in part by the Fundamental Research Funds for the Central Universities under Grant 2023MS113。
文摘In response to the requirements for large-scale device access and ultra-reliable and low-latency communication in the power internet of things,unmanned aerial vehicle-assisted multi-access edge computing can be used to realize flexible access to power services and update large amounts of information in a timely manner.By considering factors such as machine communication traffic,MAC competition access,and information freshness,this paper develops a cross-layer computing framework in which the peak Age of Information(Ao I)provides a statistical delay boundary in the finite blocklength regime.We also propose a deep machine learning-based multi-access edge computing offloading algorithm.First,a traffic arrival model is established in which the time interval follows the Beta distribution,and then a business service model is proposed based on the carrier sense multiple access with collision avoidance algorithm.The peak Ao I boundary performance of multiple access is evaluated according to stochastic network calculus theory.Finally,an unmanned aerial vehicle-assisted multilevel offloading model with cache is designed,in which the peak Ao I violation probability and energy consumption provide the optimization goals.The optimal offloading strategy is obtained using deep reinforcement learning.Compared with baseline schemes based on non-cooperative game theory with stochastic learning automata and random edge unloading,the proposed algorithm improves the overall performance by approximately 3.52%and 20.73%,respectively,and provides superior deterministic offloading performance by using the peak Ao I boundary.
基金support from the National Natural Science Foundation of China(grant Nos.:52303371,W2521021)Guangdong Science and Technology Department(grant Nos.:STKJ2023075,2022A1515110209,2021B0301030005)Education foundation of Guangdong Technion-Israel institute of Technology,and the Key Discipline(KD)Fund,the Technion,and the Start-Up Fund from Guangdong Technion.
文摘Hydrogels emerge as a promising electrode material for scalp electroencephalogram monitoring,which stands as a pivotal technique in neuroscience,enabling real-time monitoring of brain activity.However,conventional hydrogel-enabled electrodes suffer from low scalp compliance,high scalpelectrode impedance,and inferior interfacial stability.Here,we propose an injectable eutectogelenabled electrode for high-quality,long-term scalp electroencephalogram monitoring.This gelatinbased eutectogel exhibits temperature-controlled reversible phase transitions,enabling rapid in-situ gelation on the scalp and forming a robust self-adhesive interface.It demonstrates exceptional mechanical durability(1000 cycles at 100%strain),robust adhesion(0.7 N cm^(-1)on human epidermis and 1.7 N cm^(-1)on Ag/AgCl electrode),and outstanding anti-drying properties(negligible water loss after 7 days).Additionally,the eutectogel shows superior healing properties,antibacterial properties,and recyclability.Furthermore,it exhibits remarkably low scalp-electrode contact impedance(<20 kΩat 16 Hz).The eutectogel is injected on the human scalp with dense hair for high-fidelity electroencephalogram recording,enabling long-term monitoring.Its practical applications include monitoring visual evoked potentials,steady-state visual evoked potentials,somatosensory evoked potentials,slow vertex response,auditory brainstem response,multi-channel cognitive electroencephalogram during various daily activities,and event-related potentials P300 signals.The eutectogel-enabled electrode provides a versatile and reliable solution for long-term electroencephalogram monitoring in diverse clinical and research settings.
基金supported by the National Natural Science Foundation of China (52303371)Guangdong Science and Technology Department (STKJ2023075, 2022A1515110209, and 2021B0301030005)+2 种基金Guangdong Education Department (2022KQNCX112)seed fund (GCII-Seed-202406) from GTIIT Changzhou Innovation Institutethe Key Discipline (KD) Fund, the Technion, and the Start-Up Fund from Guangdong Technion。
文摘Soft electronics have seen extensive development due to their lightness,outstanding mechanical flexibility,and biocompatibility,which make them ideal for a variety of applications,including health monitoring,human-machine interfaces,and advanced augmented reality/virtual reality communications[1,2].Ionic liquid(IL)-based conductive hydrogels are typically made up of a polymer network swollen with IL,which are organic salts in a liquid state at or near room temperature,rather than traditional inorganic/organic salt electrolyte solutions[3-5].These hydrogels leverage the unique properties of IL,such as high ionic conductivity,nonvolatility,and thermal stability,to create a flexible conductive material suitable for various applications in soft electronics,such as actuators,wearable sensors,and stretchable energy generation/storage devices[6-8].
