High-order quantum coherence reveals the statistical correlation of quantum particles. Manipulation of quantum coherence of light in the temporal domain enables the production of the single-photon source, which has be...High-order quantum coherence reveals the statistical correlation of quantum particles. Manipulation of quantum coherence of light in the temporal domain enables the production of the single-photon source, which has become one of the most important quantum resources. High-order quantum coherence in the spatial domain plays a crucial role in a variety of applications, such as quantum imaging, holography, and microscopy. However, the active control of second-order spatial quantum coherence remains a challenging task. Here we predict theoretically and demonstrate experimentally the first active manipulation of second-order spatial quantum coherence,which exhibits the capability of switching between bunching and anti-bunching, by mapping the entanglement of spatially structured photons. We also show that signal processing based on quantum coherence exhibits robust resistance to intensity disturbance. Our findings not only enhance existing applications but also pave the way for broader utilization of higher-order spatial quantum coherence.展开更多
Because of its advantages of light weight, high strength and convenient construction, steel structure has gradually become the first choice for large-span and high-rise structures. The use of high strength steel in bu...Because of its advantages of light weight, high strength and convenient construction, steel structure has gradually become the first choice for large-span and high-rise structures. The use of high strength steel in building engineering can reduce the section size of components and the weight of the structure, thus increasing the building area. But steel is not fire-resistant, when the temperature reaches 600<span style="white-space:nowrap;">°</span>C, steel loses most of the stiffness and strength. Therefore, it is of great significance to study the fire resistance of steel structures, and the mechanical properties of steel structures at high temperature are the foundation of the fire resistance research. The mechanical properties of steel after high temperature are the basis for the safety assessment of steel structure after fire. Therefore, this paper studies the mechanical properties of Q345 steel after high temperature cooling.展开更多
The microstructure–mechanical property relationship of a Cu-bearing low-carbon high-strength low-alloy steel,subjected to a novel multistage heat treatment including quenching(Q),lamellarization(L)and tempering(T),is...The microstructure–mechanical property relationship of a Cu-bearing low-carbon high-strength low-alloy steel,subjected to a novel multistage heat treatment including quenching(Q),lamellarization(L)and tempering(T),is presented.Yield strength of 989.5 MPa and average toughness at-80℃of 41 J were obtained in this steel after quenching and tempering(QT)heat treatments.Specimen QLT gained a little lower yield strength(982.5 MPa),but greatly enhanced average toughness at-80℃(137 J).To further clarify the strengthening and toughening mechanisms in specimen QLT,parameters of microstructural characteristic and crack propagation process were compared and analyzed for specimens Q,QL,QT and QLT.The microstructure of tempered martensite/bainite(M/B)in specimen QT changed to refined tempered M/B matrix mixed with minor IF(inter-critical ferrite)in specimen QLT.Cu-rich precipitates existed in tempered M/B for both specimens QT and QLT,as well as in IF.Compared with QT,adding a lamellarization step before tempering made the effective grains of specimen QLT refined and also led to coarser Cu-rich precipitates in tempered M/B matrix.The weaker strengthening effect of coarser Cu-rich precipitates should be a key reason for the slightly lower yield strength in specimen QLT than in specimen QT.No austenite was found in all specimens Q,QL,QT and QLT.Specimen QLT showed purely ductile fracture mode at-80℃due to the refined effective grains.The greatly improved toughness is mainly attributed to the enhanced energy of crack propagation.The combination of refined microstructure,softened matrix and deformation of minor'soft'IF during crack propagation led to the most superior toughness of specimen QLT among all specimens.展开更多
背景胃底腺型胃癌(gastric adenocarcinoma of the fundic gland type,GA-FG)是近年来新发现的一种胃癌类型,不同于传统的肠癌和弥漫性胃癌,是一种分化良好的肿瘤.预计GA-FG在所有胃癌中的比例将越来越高,但目前内镜医师及临床病理学家...背景胃底腺型胃癌(gastric adenocarcinoma of the fundic gland type,GA-FG)是近年来新发现的一种胃癌类型,不同于传统的肠癌和弥漫性胃癌,是一种分化良好的肿瘤.预计GA-FG在所有胃癌中的比例将越来越高,但目前内镜医师及临床病理学家对该病认识不足容易导致误诊.目的本文通过对该病的内镜、临床及病理特点进行系统回顾,旨在增加该疾病的诊断率并减少漏诊及误诊.方法在Pubmed及中国知网收集2007-01/2022-03期间公开发表的中英文文献中报道的胃底腺型胃癌患者临床、病理及内镜资料,并进行回顾分析.结果共收集67篇文献中320例胃底腺型胃癌患者共322处病变相关资料.病变多位于胃上1/3(81.6%),病变平均大小9.66 mm(1 mm-85 mm),约76.88%病变大体形态为隆起型.窄带成像观察病变表面可见微血管扩张及微腺体结构紊乱或增粗.所有病变中主细胞分化型约占74.84%,显著表达MUC6及胃蛋白酶原,预后良好.结论胃底腺型胃癌发病率低,内镜下完整切除及外科手术可到达治愈性切除的目的,预后较好,但易误诊,诊断时应结合其临床病理学特点,从而减少误诊及漏诊率.展开更多
In reinforcement learning an agent may explore ineffectively when dealing with sparse reward tasks where finding a reward point is difficult.To solve the problem,we propose an algorithm called hierarchical deep reinfo...In reinforcement learning an agent may explore ineffectively when dealing with sparse reward tasks where finding a reward point is difficult.To solve the problem,we propose an algorithm called hierarchical deep reinforcement learning with automatic sub-goal identification via computer vision(HADS)which takes advantage of hierarchical reinforcement learning to alleviate the sparse reward problem and improve efficiency of exploration by utilizing a sub-goal mechanism.HADS uses a computer vision method to identify sub-goals automatically for hierarchical deep reinforcement learning.Due to the fact that not all sub-goal points are reachable,a mechanism is proposed to remove unreachable sub-goal points so as to further improve the performance of the algorithm.HADS involves contour recognition to identify sub-goals from the state image where some salient states in the state image may be recognized as sub-goals,while those that are not will be removed based on prior knowledge.Our experiments verified the effect of the algorithm.展开更多
Based on molecular phylogeny of the Chinese white cross-band krait, Bungarus multicinctus, several individuals from southwestern and southern China were found to be nested within putative species B. candidus(Linnaeus...Based on molecular phylogeny of the Chinese white cross-band krait, Bungarus multicinctus, several individuals from southwestern and southern China were found to be nested within putative species B. candidus(Linnaeus, 1758) with high support values. Morphological examination also indicated these specimens were identical to B. candidus. We concluded that the Chinese white cross-band krait, previously identified as B. multicinctus in southwest and south China, should be recognized as B. candidus, a new record in China, and B. m. wanghaoti should be invalid. B. multicinctus is recurrently limited to southern China within China.展开更多
The Finite-Difference Time-Domain (FDTD) method is a well-known technique for the analysis of quantum devices. It solves a discretized Schrodinger equation in an iterative process. However, the method provides only a ...The Finite-Difference Time-Domain (FDTD) method is a well-known technique for the analysis of quantum devices. It solves a discretized Schrodinger equation in an iterative process. However, the method provides only a second-order accurate numerical solution and requires that the spatial grid size and time step should satisfy a very restricted condition in order to prevent the numerical solution from diverging. In this article, we present a generalized FDTD method with absorbing boundary condition for solving the one-dimensional (1D) time-dependent Schr?dinger equation and obtain a more relaxed condition for stability. The generalized FDTD scheme is tested by simulating a particle moving in free space and then hitting an energy potential. Numerical results coincide with those obtained based on the theoretical analysis.展开更多
Organic–inorganic hybrid perovskite materials have been focusing more attention in the field of self-powered photodetectors due to their superb photoelectric properties.However,a universal growth approach is required...Organic–inorganic hybrid perovskite materials have been focusing more attention in the field of self-powered photodetectors due to their superb photoelectric properties.However,a universal growth approach is required and challenging to realize vertically oriented growth and grain boundary fusion of 2D and 3D perovskite grains to promote ordered carrier transport,which determines superior photoresponse and high stability.Herein,a general thermal-pressed(TP)strategy is designed to solve the above issues,achieving uniaxial orientation and single-grain penetration along the film thickness direction.It constructs the efficient channel for ordered carrier transport between two electrodes.Combining of the improved crystal quality and lower trap-state density,the quasi-2D and 3D perovskite-based self-powered photodetector devices(with/without hole transport layer)all exhibit giant and stable photoresponse in a wide spectrum range and specific wavelength laser.For the MAPbI_(3)-based self-powered photodetectors,the largest R_(λ) value is as high as 0.57 A W^(−1)at 760 nm,which is larger than most reported results.Meanwhile,under laser illumination(532 nm),the FPEA_(2)MA_(4)Pb_(5)I_(16)-based device exhibits a high responsivity(0.4 A W^(−1)) value,which is one of the best results in 2DRP self-powered photodetectors.In addition,fast response,ultralow detection limit,and markedly improved humidity,optical and heat stabilities are clearly demonstrated for these TP-based devices.展开更多
Chirality is a fascinating and essential feature of life and highly associated with many significant pharmaceutical,chemical,and biological processes.The construction of chiral recognition platform is a hot research t...Chirality is a fascinating and essential feature of life and highly associated with many significant pharmaceutical,chemical,and biological processes.The construction of chiral recognition platform is a hot research topic and challenging assignment.Herein,we report an electrochemical method by diffe rential pulse voltammetry(DPV) for the enantioselective recognition of chiral drug propranolol(R/SPPL) through a nanochannel platform based on the N-acetyl-L-cysteine functionalized pillar[5]arenes derivative NALC-P5 and the porous polycarbonate membrane.The chiral discrimination depends on the diffe rence in the supramolecular host-vip interaction between the chiral NALC-P5 and the R/S-PPL.The transmission rate of the R/S-PPL can be regulated in the nanochannel and we can achieve the selective transport of the chiral drugs.This simple electrochemical technique has potential applications as a general platform for the recognition of chiral molecules.展开更多
A superior combination of yield strength(1001 MPa)and-20℃ impact toughness(166 J)was obtained in Nb-V-Timicroalloyed Ni-Cr-Mo-Cu steel treated by direct quenching and tempering route(DQT).The tested steels treated by...A superior combination of yield strength(1001 MPa)and-20℃ impact toughness(166 J)was obtained in Nb-V-Timicroalloyed Ni-Cr-Mo-Cu steel treated by direct quenching and tempering route(DQT).The tested steels treated by DQT route and re-austenitization and tempering route(QT)were compared with each other in terms of mechanical properties and microstructures characterized by optical microscopy,transmission electron microscopy,X-ray diffraction,electron back-scattered diffraction method and so on.Strength and Vickers hardness of the tested steel treated by the above two routes vary with isothermal aging temperature(400-600℃),shown as under-aged state,peak-aged state and overaged state.All DQT specimens show higher strength and Vickers hardness than QT specimens with the same aging condition.Furthermore,the largest difference of yield strength between DQT and QT specimens was shown in DQT600 and QT600 specimens.DQT600 or QT600 specimens refers to direct quenched(DQ)or quenched(Q)specimens isothermally aged at 600℃.The main disparities in quenched microstructure between DQ and Q specimens are mainly in morphology of prior austenite grains,dislocation density of martensite matrix and solution amount of Nb and Mo elements dissolving in martensite matrix,which play key roles in affecting microstructure and mechanical properties of DQT and QT specimens.Higher dislocation density of matrix and finer average diameter of both MC(M is any combination of Nb,Mo and V)and Cu-rich particles were shown in DQT600 specimens than in QT600 specimens.Strengthening from dislocations and nanosized MC and Cu-rich particles mainly leads to the largest difference of yield strength between DQT600 and QT600 specimens.In addition,strong dislocation strengthening and precipitation strengthening in DQT600 specimen also elevated its ductile-to-brittle-transition-temperature,compared with QT600 specimen.展开更多
Policy iteration,which evaluates and improves the control policy iteratively,is a reinforcement learning method.Policy evaluation with the least-squares method can draw more useful information from the empirical data ...Policy iteration,which evaluates and improves the control policy iteratively,is a reinforcement learning method.Policy evaluation with the least-squares method can draw more useful information from the empirical data and therefore improve the data validity.However,most existing online least-squares policy iteration methods only use each sample just once,resulting in the low utilization rate.With the goal of improving the utilization efficiency,we propose an experience replay for least-squares policy iteration(ERLSPI)and prove its convergence.ERLSPI method combines online least-squares policy iteration method with experience replay,stores the samples which are generated online,and reuses these samples with least-squares method to update the control policy.We apply the ERLSPI method for the inverted pendulum system,a typical benchmark testing.The experimental results show that the method can effectively take advantage of the previous experience and knowledge,improve the empirical utilization efficiency,and accelerate the convergence speed.展开更多
Yujingyou 50 is a new high-quality late indica hybrid rice combination selected by Institute of Grain and Oil Crops,Nanchang Academy of Agricultural Sciences and Hunan Zhonglang seed Industry Co.,Ltd.The combination m...Yujingyou 50 is a new high-quality late indica hybrid rice combination selected by Institute of Grain and Oil Crops,Nanchang Academy of Agricultural Sciences and Hunan Zhonglang seed Industry Co.,Ltd.The combination matured 3 d earlier than Tianyouzhan.It has the characteristics of moderate plant type,broad and long flag leaves,general tillering ability,colorless palea tips,large panicles with many grains,high seed setting rate,average 1000-grain weight,good color change at maturity,and rice quality reaching grade 2 of ministry standard.It was approved by the Jiangxi Provincial Crop Variety Approval Committee on March 18,2021.This paper introduced the breeding process,characteristics,cultivation techniques and key points of seed production of this variety.展开更多
[Objectives]This study was conducted to screen rice varieties suitable for planting in Nanchang City with high quality,high yield,good yield,and strong disease and stress resistance.[Methods]Seven new late indica hybr...[Objectives]This study was conducted to screen rice varieties suitable for planting in Nanchang City with high quality,high yield,good yield,and strong disease and stress resistance.[Methods]Seven new late indica hybrid rice combinations with good quality bred in Jiangxi Province in recent years and seven new late indica hybrid rice combinations with good quality bred by Nanchang Academy of Agricultural Sciences were introduced,and compared with Tianyouhuazhan as a control.[Results]The rice quality and taste of the tested combinations were better than those of the control.Among the tested combinations,Yuliangyoufuxiangzhan,Xintaiyousizhan,Yuxiangliangyou No.8 and Guangheyou 33 had good stress resistance,high yield and good rice quality.[Conclusions]This study provides a theoretical basis for the selection and breeding of new rice varieties in Nanchang City.展开更多
Yuanliangyou 1000 is new combination of semilate rice bred by Yuan S and R900 by Institute of Grain and Oil Crops of Nanchang Academy of Agricultural Science,Yuanshi Seed Industry High Tech Co.,Ltd.and Jiangxi Pusheng...Yuanliangyou 1000 is new combination of semilate rice bred by Yuan S and R900 by Institute of Grain and Oil Crops of Nanchang Academy of Agricultural Science,Yuanshi Seed Industry High Tech Co.,Ltd.and Jiangxi Pusheng Agricultural Development Co.,Ltd.It passed through new variety certification of Jiangxi Province in 2017,and approval number was Ganshendao 20170020,which was suitable for plantation of semilate rice in Jiangxi.In this paper,breeding process,combination characteristic,main cultivation technique and seed production technology of Yuanliangyou 1000 were introduced.展开更多
Age of knowledge explosion requires us not only to have the ability to get useful information which represented by data but also to find knowledge in information. Human Genome Project achieved large amount of such bio...Age of knowledge explosion requires us not only to have the ability to get useful information which represented by data but also to find knowledge in information. Human Genome Project achieved large amount of such biological data, and people found clustering is a promising approach to analyze those biological data for knowledge hidden. The researches on biological data go to in-depth gradually and so are the clustering algorithms. This article mainly introduces current broad-used clustering algorithms, including the main idea, improvements, key technology, advantage and disadvantage, and the applications in biological field as well as the problems they solve. What’s more, this article roughly introduces some database used in biological field.展开更多
In this paper, we conduct research on the lexical chunks and the interactive education mode and the corresponding applications on the teaching of English linguistics. The ultimate goal of the teaching is to improve th...In this paper, we conduct research on the lexical chunks and the interactive education mode and the corresponding applications on the teaching of English linguistics. The ultimate goal of the teaching is to improve the level of the students, exert students' initiative and creativity, in order to achieve this goal, teachers need to according to the teaching object, choose the appropriate teaching methods., diversified teaching method is multivariate, teaching method of the multivariate interactive for teachers to provide a liberal idea, on the teaching method all rivers run into sea, not stick to one method, in order to further play the advantages of various teaching methods, optimizing classroom teaching, improve teaching efficiency and ensure the quality of teaching. Each teaching method has its advantages and disadvantages, comprehensive methods while the teachers can foster strengths and circumvent weaknesses, fully mobilize students' enthusiasm, exert students' initiative and creativity, and improve the level of students. Under this background, we integrate the lexical chunks and the interactive education mode to construct the novel education paradigm that is innovative.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos.12234009,12275048,12304359,and 12274215)the National Key R&D Program of China (Grant No.2020YFA0309500)+4 种基金the Innovation Program for Quantum Science and Technology (Grant No.2021ZD0301400)the Program for Innovative Talents and Entrepreneurs in Jiangsu,the Natural Science Foundation of Jiangsu Province (Grant No.BK20220759)the Key R&D Program of Guangdong Province,China (Grant No.2020B0303010001)the China Postdoctoral Science Foundation (Grant No.2023M731611)the Jiangsu Funding Program for Excellent Postdoctoral Talent (Grant No.2023ZB717)。
文摘High-order quantum coherence reveals the statistical correlation of quantum particles. Manipulation of quantum coherence of light in the temporal domain enables the production of the single-photon source, which has become one of the most important quantum resources. High-order quantum coherence in the spatial domain plays a crucial role in a variety of applications, such as quantum imaging, holography, and microscopy. However, the active control of second-order spatial quantum coherence remains a challenging task. Here we predict theoretically and demonstrate experimentally the first active manipulation of second-order spatial quantum coherence,which exhibits the capability of switching between bunching and anti-bunching, by mapping the entanglement of spatially structured photons. We also show that signal processing based on quantum coherence exhibits robust resistance to intensity disturbance. Our findings not only enhance existing applications but also pave the way for broader utilization of higher-order spatial quantum coherence.
文摘Because of its advantages of light weight, high strength and convenient construction, steel structure has gradually become the first choice for large-span and high-rise structures. The use of high strength steel in building engineering can reduce the section size of components and the weight of the structure, thus increasing the building area. But steel is not fire-resistant, when the temperature reaches 600<span style="white-space:nowrap;">°</span>C, steel loses most of the stiffness and strength. Therefore, it is of great significance to study the fire resistance of steel structures, and the mechanical properties of steel structures at high temperature are the foundation of the fire resistance research. The mechanical properties of steel after high temperature are the basis for the safety assessment of steel structure after fire. Therefore, this paper studies the mechanical properties of Q345 steel after high temperature cooling.
基金National Key Research and Development Program of China(No.2017YFB0304501).
文摘The microstructure–mechanical property relationship of a Cu-bearing low-carbon high-strength low-alloy steel,subjected to a novel multistage heat treatment including quenching(Q),lamellarization(L)and tempering(T),is presented.Yield strength of 989.5 MPa and average toughness at-80℃of 41 J were obtained in this steel after quenching and tempering(QT)heat treatments.Specimen QLT gained a little lower yield strength(982.5 MPa),but greatly enhanced average toughness at-80℃(137 J).To further clarify the strengthening and toughening mechanisms in specimen QLT,parameters of microstructural characteristic and crack propagation process were compared and analyzed for specimens Q,QL,QT and QLT.The microstructure of tempered martensite/bainite(M/B)in specimen QT changed to refined tempered M/B matrix mixed with minor IF(inter-critical ferrite)in specimen QLT.Cu-rich precipitates existed in tempered M/B for both specimens QT and QLT,as well as in IF.Compared with QT,adding a lamellarization step before tempering made the effective grains of specimen QLT refined and also led to coarser Cu-rich precipitates in tempered M/B matrix.The weaker strengthening effect of coarser Cu-rich precipitates should be a key reason for the slightly lower yield strength in specimen QLT than in specimen QT.No austenite was found in all specimens Q,QL,QT and QLT.Specimen QLT showed purely ductile fracture mode at-80℃due to the refined effective grains.The greatly improved toughness is mainly attributed to the enhanced energy of crack propagation.The combination of refined microstructure,softened matrix and deformation of minor'soft'IF during crack propagation led to the most superior toughness of specimen QLT among all specimens.
文摘背景胃底腺型胃癌(gastric adenocarcinoma of the fundic gland type,GA-FG)是近年来新发现的一种胃癌类型,不同于传统的肠癌和弥漫性胃癌,是一种分化良好的肿瘤.预计GA-FG在所有胃癌中的比例将越来越高,但目前内镜医师及临床病理学家对该病认识不足容易导致误诊.目的本文通过对该病的内镜、临床及病理特点进行系统回顾,旨在增加该疾病的诊断率并减少漏诊及误诊.方法在Pubmed及中国知网收集2007-01/2022-03期间公开发表的中英文文献中报道的胃底腺型胃癌患者临床、病理及内镜资料,并进行回顾分析.结果共收集67篇文献中320例胃底腺型胃癌患者共322处病变相关资料.病变多位于胃上1/3(81.6%),病变平均大小9.66 mm(1 mm-85 mm),约76.88%病变大体形态为隆起型.窄带成像观察病变表面可见微血管扩张及微腺体结构紊乱或增粗.所有病变中主细胞分化型约占74.84%,显著表达MUC6及胃蛋白酶原,预后良好.结论胃底腺型胃癌发病率低,内镜下完整切除及外科手术可到达治愈性切除的目的,预后较好,但易误诊,诊断时应结合其临床病理学特点,从而减少误诊及漏诊率.
基金supported by the National Natural Science Foundation of China(61303108)Suzhou Key Industries Technological Innovation-Prospective Applied Research Project(SYG201804)+2 种基金A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the Fundamental Research Funds for the Gentral UniversitiesJLU(93K172020K25)。
文摘In reinforcement learning an agent may explore ineffectively when dealing with sparse reward tasks where finding a reward point is difficult.To solve the problem,we propose an algorithm called hierarchical deep reinforcement learning with automatic sub-goal identification via computer vision(HADS)which takes advantage of hierarchical reinforcement learning to alleviate the sparse reward problem and improve efficiency of exploration by utilizing a sub-goal mechanism.HADS uses a computer vision method to identify sub-goals automatically for hierarchical deep reinforcement learning.Due to the fact that not all sub-goal points are reachable,a mechanism is proposed to remove unreachable sub-goal points so as to further improve the performance of the algorithm.HADS involves contour recognition to identify sub-goals from the state image where some salient states in the state image may be recognized as sub-goals,while those that are not will be removed based on prior knowledge.Our experiments verified the effect of the algorithm.
基金supported by the National Natural Science Foundation of China(31071892,31372152)Department of Education of Sichuan Province(13TD0027)to PGSoutheast Asia Biodiversity Research Institute,Chinese Academy of Sciences(Y4ZK111B01)to JC
文摘Based on molecular phylogeny of the Chinese white cross-band krait, Bungarus multicinctus, several individuals from southwestern and southern China were found to be nested within putative species B. candidus(Linnaeus, 1758) with high support values. Morphological examination also indicated these specimens were identical to B. candidus. We concluded that the Chinese white cross-band krait, previously identified as B. multicinctus in southwest and south China, should be recognized as B. candidus, a new record in China, and B. m. wanghaoti should be invalid. B. multicinctus is recurrently limited to southern China within China.
文摘The Finite-Difference Time-Domain (FDTD) method is a well-known technique for the analysis of quantum devices. It solves a discretized Schrodinger equation in an iterative process. However, the method provides only a second-order accurate numerical solution and requires that the spatial grid size and time step should satisfy a very restricted condition in order to prevent the numerical solution from diverging. In this article, we present a generalized FDTD method with absorbing boundary condition for solving the one-dimensional (1D) time-dependent Schr?dinger equation and obtain a more relaxed condition for stability. The generalized FDTD scheme is tested by simulating a particle moving in free space and then hitting an energy potential. Numerical results coincide with those obtained based on the theoretical analysis.
基金the National Natural Science Foundation of China(NSFC,No.51872172,51972197)Natural Science Foundation of Shandong Province(ZR2019MEM021)Young Scholars Program of Shandong University.
文摘Organic–inorganic hybrid perovskite materials have been focusing more attention in the field of self-powered photodetectors due to their superb photoelectric properties.However,a universal growth approach is required and challenging to realize vertically oriented growth and grain boundary fusion of 2D and 3D perovskite grains to promote ordered carrier transport,which determines superior photoresponse and high stability.Herein,a general thermal-pressed(TP)strategy is designed to solve the above issues,achieving uniaxial orientation and single-grain penetration along the film thickness direction.It constructs the efficient channel for ordered carrier transport between two electrodes.Combining of the improved crystal quality and lower trap-state density,the quasi-2D and 3D perovskite-based self-powered photodetector devices(with/without hole transport layer)all exhibit giant and stable photoresponse in a wide spectrum range and specific wavelength laser.For the MAPbI_(3)-based self-powered photodetectors,the largest R_(λ) value is as high as 0.57 A W^(−1)at 760 nm,which is larger than most reported results.Meanwhile,under laser illumination(532 nm),the FPEA_(2)MA_(4)Pb_(5)I_(16)-based device exhibits a high responsivity(0.4 A W^(−1)) value,which is one of the best results in 2DRP self-powered photodetectors.In addition,fast response,ultralow detection limit,and markedly improved humidity,optical and heat stabilities are clearly demonstrated for these TP-based devices.
基金financially supported by the National Key Research and Development Program of China(No.2018YFD0200102)the National Natural Science Foundation of China(Nos.21772055,21572076,21807083,21911530178)+1 种基金the Program for Innovative Teams of Outstanding Young and Middleaged Researchers in the Higher Education Institutions of Hubei Province(No.T201702)the 111 Project(No.B17019E)。
文摘Chirality is a fascinating and essential feature of life and highly associated with many significant pharmaceutical,chemical,and biological processes.The construction of chiral recognition platform is a hot research topic and challenging assignment.Herein,we report an electrochemical method by diffe rential pulse voltammetry(DPV) for the enantioselective recognition of chiral drug propranolol(R/SPPL) through a nanochannel platform based on the N-acetyl-L-cysteine functionalized pillar[5]arenes derivative NALC-P5 and the porous polycarbonate membrane.The chiral discrimination depends on the diffe rence in the supramolecular host-vip interaction between the chiral NALC-P5 and the R/S-PPL.The transmission rate of the R/S-PPL can be regulated in the nanochannel and we can achieve the selective transport of the chiral drugs.This simple electrochemical technique has potential applications as a general platform for the recognition of chiral molecules.
基金supported by the National Key R&D Program of China(Nos.2017YFB0701802.2017YFB0703002 and 2017YFB0304501)the National Natural Science Foundation of China(No.51701044).
文摘A superior combination of yield strength(1001 MPa)and-20℃ impact toughness(166 J)was obtained in Nb-V-Timicroalloyed Ni-Cr-Mo-Cu steel treated by direct quenching and tempering route(DQT).The tested steels treated by DQT route and re-austenitization and tempering route(QT)were compared with each other in terms of mechanical properties and microstructures characterized by optical microscopy,transmission electron microscopy,X-ray diffraction,electron back-scattered diffraction method and so on.Strength and Vickers hardness of the tested steel treated by the above two routes vary with isothermal aging temperature(400-600℃),shown as under-aged state,peak-aged state and overaged state.All DQT specimens show higher strength and Vickers hardness than QT specimens with the same aging condition.Furthermore,the largest difference of yield strength between DQT and QT specimens was shown in DQT600 and QT600 specimens.DQT600 or QT600 specimens refers to direct quenched(DQ)or quenched(Q)specimens isothermally aged at 600℃.The main disparities in quenched microstructure between DQ and Q specimens are mainly in morphology of prior austenite grains,dislocation density of martensite matrix and solution amount of Nb and Mo elements dissolving in martensite matrix,which play key roles in affecting microstructure and mechanical properties of DQT and QT specimens.Higher dislocation density of matrix and finer average diameter of both MC(M is any combination of Nb,Mo and V)and Cu-rich particles were shown in DQT600 specimens than in QT600 specimens.Strengthening from dislocations and nanosized MC and Cu-rich particles mainly leads to the largest difference of yield strength between DQT600 and QT600 specimens.In addition,strong dislocation strengthening and precipitation strengthening in DQT600 specimen also elevated its ductile-to-brittle-transition-temperature,compared with QT600 specimen.
文摘Policy iteration,which evaluates and improves the control policy iteratively,is a reinforcement learning method.Policy evaluation with the least-squares method can draw more useful information from the empirical data and therefore improve the data validity.However,most existing online least-squares policy iteration methods only use each sample just once,resulting in the low utilization rate.With the goal of improving the utilization efficiency,we propose an experience replay for least-squares policy iteration(ERLSPI)and prove its convergence.ERLSPI method combines online least-squares policy iteration method with experience replay,stores the samples which are generated online,and reuses these samples with least-squares method to update the control policy.We apply the ERLSPI method for the inverted pendulum system,a typical benchmark testing.The experimental results show that the method can effectively take advantage of the previous experience and knowledge,improve the empirical utilization efficiency,and accelerate the convergence speed.
基金Supported by Jiangxi Provincial R&D Program(20181BBF60007)。
文摘Yujingyou 50 is a new high-quality late indica hybrid rice combination selected by Institute of Grain and Oil Crops,Nanchang Academy of Agricultural Sciences and Hunan Zhonglang seed Industry Co.,Ltd.The combination matured 3 d earlier than Tianyouzhan.It has the characteristics of moderate plant type,broad and long flag leaves,general tillering ability,colorless palea tips,large panicles with many grains,high seed setting rate,average 1000-grain weight,good color change at maturity,and rice quality reaching grade 2 of ministry standard.It was approved by the Jiangxi Provincial Crop Variety Approval Committee on March 18,2021.This paper introduced the breeding process,characteristics,cultivation techniques and key points of seed production of this variety.
基金Supported by Demonstration of Green and High-efficiency Cultivation Techniques for High-quality Rice(GCJ[2011]250)。
文摘[Objectives]This study was conducted to screen rice varieties suitable for planting in Nanchang City with high quality,high yield,good yield,and strong disease and stress resistance.[Methods]Seven new late indica hybrid rice combinations with good quality bred in Jiangxi Province in recent years and seven new late indica hybrid rice combinations with good quality bred by Nanchang Academy of Agricultural Sciences were introduced,and compared with Tianyouhuazhan as a control.[Results]The rice quality and taste of the tested combinations were better than those of the control.Among the tested combinations,Yuliangyoufuxiangzhan,Xintaiyousizhan,Yuxiangliangyou No.8 and Guangheyou 33 had good stress resistance,high yield and good rice quality.[Conclusions]This study provides a theoretical basis for the selection and breeding of new rice varieties in Nanchang City.
基金Supported by Collaborative Innovation Project of Jiangxi Modern Agriculture Science Research(JXXTCX2015001-002-05)Extension Projects of New Varieties and Technology in Nanchang
文摘Yuanliangyou 1000 is new combination of semilate rice bred by Yuan S and R900 by Institute of Grain and Oil Crops of Nanchang Academy of Agricultural Science,Yuanshi Seed Industry High Tech Co.,Ltd.and Jiangxi Pusheng Agricultural Development Co.,Ltd.It passed through new variety certification of Jiangxi Province in 2017,and approval number was Ganshendao 20170020,which was suitable for plantation of semilate rice in Jiangxi.In this paper,breeding process,combination characteristic,main cultivation technique and seed production technology of Yuanliangyou 1000 were introduced.
文摘Age of knowledge explosion requires us not only to have the ability to get useful information which represented by data but also to find knowledge in information. Human Genome Project achieved large amount of such biological data, and people found clustering is a promising approach to analyze those biological data for knowledge hidden. The researches on biological data go to in-depth gradually and so are the clustering algorithms. This article mainly introduces current broad-used clustering algorithms, including the main idea, improvements, key technology, advantage and disadvantage, and the applications in biological field as well as the problems they solve. What’s more, this article roughly introduces some database used in biological field.
文摘In this paper, we conduct research on the lexical chunks and the interactive education mode and the corresponding applications on the teaching of English linguistics. The ultimate goal of the teaching is to improve the level of the students, exert students' initiative and creativity, in order to achieve this goal, teachers need to according to the teaching object, choose the appropriate teaching methods., diversified teaching method is multivariate, teaching method of the multivariate interactive for teachers to provide a liberal idea, on the teaching method all rivers run into sea, not stick to one method, in order to further play the advantages of various teaching methods, optimizing classroom teaching, improve teaching efficiency and ensure the quality of teaching. Each teaching method has its advantages and disadvantages, comprehensive methods while the teachers can foster strengths and circumvent weaknesses, fully mobilize students' enthusiasm, exert students' initiative and creativity, and improve the level of students. Under this background, we integrate the lexical chunks and the interactive education mode to construct the novel education paradigm that is innovative.