Although crystalline anode materials with long-range ordered lattice structure are in favor of facilitating the electron transfer,their structures are easily disrupted during long-term cycling due to the continuous em...Although crystalline anode materials with long-range ordered lattice structure are in favor of facilitating the electron transfer,their structures are easily disrupted during long-term cycling due to the continuous embedding/de-embedding of lithium ions.In contrast,the amorphous materials have abundant defects and lithium ion storage sites,refl ecting a superior reaction kinetics and long-term cycling stability.Here,we synthesize an integrated hybrid anode by in-situ loading amorphous NiMo_(3)S_(13)nanosheets on nickel foam substrate.Benefi ting from the introduction of Ni^(2+)that amorphizes the molybdenumsulfur clusters,the assembled lithium ion battery based on the integrated NiMo_(3)S_(13)/nickel foam anode delivers a specifi c capacity up to 1659 mA·h·g^(−1)at a current density of 0.6 A·g^(−1)and exhibits superior rate/cycling performance.展开更多
目的:建立科学的宽体金线蛭种蛭筛选原则,并对产茧后药材进行质量评价。方法:从微山湖地区采集野生宽体金线蛭1193条,对体质量和生殖环带发育等群体特征进行考察。将种蛭分为10、15、20 g 3个试验组,建立卵茧成熟度观察方法以判断适宜...目的:建立科学的宽体金线蛭种蛭筛选原则,并对产茧后药材进行质量评价。方法:从微山湖地区采集野生宽体金线蛭1193条,对体质量和生殖环带发育等群体特征进行考察。将种蛭分为10、15、20 g 3个试验组,建立卵茧成熟度观察方法以判断适宜的挖茧时机,通过产茧数、茧体积、出苗数等指标考察体质量对宽体金线蛭繁殖性能的影响。依照2015年版《中华人民共和国药典》对产茧后水蛭药材的性状和抗凝血酶活性进行质量评价。结果:微山湖地区宽体金线蛭野生种群的体质量普遍较小,15 g及以上的种蛭仅占样本群体的19.53%;宽体金线蛭的繁殖性能随种蛭体质量的增加而显著提高,20 g试验组的产茧数(5.9个)和出苗数(37.3条)分别是10 g试验组的1.59倍和1.45倍。产茧后种蛭的死亡率和体质量损失率可高达37%和59%,药材厚度仅为产茧前的49%~72%,腥味散失严重、脆度下降,但产茧前后抗凝血酶活性变化不大,均为3~5 U·g^-1。结论:微山湖地区野生宽体金线蛭的种群有退化趋势,建议使用15 g及以上的种蛭进行繁殖生产。产茧后药材的商品规格和等级较低,不适宜作为饮片直接用于临床。展开更多
Background:Until January 18,2021,coronavirus disease-2019(COVID-19)has infected more than 93 million individuals and has caused a certain degree of panic.Viral pneumonia caused by common viruses such as respiratory sy...Background:Until January 18,2021,coronavirus disease-2019(COVID-19)has infected more than 93 million individuals and has caused a certain degree of panic.Viral pneumonia caused by common viruses such as respiratory syncytial virus,rhinovirus,human metapneumovirus,human bocavirus,and parainfluenza viruses have been more common in children.However,the incidence of COVID-19 in children was significantly lower than that in adults.The purpose of this study was to describe the clinical manifestations,treatment and outcomes of COVID-19 in children compared with those of other sources of viral pneumonia diagnosed during the COVID-19 outbreak.Methods:Children with COVID-19 and viral pneumonia admitted to 20 hospitals were enrolled in this retrospective multi-center cohort study.A total of 64 children with COVID-19 were defined as the COVID-19 cohort,of which 40 children who developed pneumonia were defined as the COVID-19 pneumonia cohort.Another 284 children with pneumonia caused by other viruses were defined as the viral pneumonia cohort.The epidemiologic,clinical,and laboratory findings were compared by Kolmogorov-Smirnov test,t-test,Mann-Whitney U test and Contingency table method.Drug usage,immunotherapy,blood transfusion,and need for oxygen support were collected as the treatment indexes.Mortality,intensive care needs and symptomatic duration were collected as the outcome indicators.Results:Compared with the viral pneumonia cohort,children in the COVID-19 cohort were mostly exposed to family members confirmed to have COVID-19(53/64 vs.23/284),were of older median age(6.3 years vs.3.2 years),and had a higher proportion of ground-glass opacity(GGO)on computed tomography(18/40 vs.0/38,P<0.001).Children in the COVID-19 pneumonia cohort had a lower proportion of severe cases(1/40 vs.38/284,P=0.048),and lower cases with high fever(3/40 vs.167/284,P<0.001),requiring intensive care(1/40 vs.32/284,P<0.047)and with shorter symptomatic duration(median 5d vs.8d,P<0.001).The proportion of cases with evaluated inflammatory indica展开更多
The long-range interaction between Rydberg-excited atoms endows a medium with large optical nonlinearity.Here,we demonstrate an optical switch to operate on a single photon from an entangled photon pair under a Rydber...The long-range interaction between Rydberg-excited atoms endows a medium with large optical nonlinearity.Here,we demonstrate an optical switch to operate on a single photon from an entangled photon pair under a Rydberg electromagnetically induced transparency configuration.With the presence of the Rydberg blockade effect,we switch on a gate field to make the atomic medium nontransparent thereby absorbing the single photon emitted from another atomic ensemble via the spontaneous fourwave mixing process.In contrast to the case without a gate field,more than 50%of the photons sent to the switch are blocked,and finally achieve an effective single-photon switch.There are on average 1-2 gate photons per effective blockade sphere in one gate pulse.This switching effect on a single entangled photon depends on the principal quantum number and the photon number of the gate field.Our experimental progress is significant in the quantum information process especially in controlling the interaction between Rydberg atoms and entangled photon pairs.展开更多
Nodal-line semimetals have become a research hot-spot due to their novel properties and great potential application in spin electronics. It is more challenging to find 2D nodal-line semimetals that can resist the spin...Nodal-line semimetals have become a research hot-spot due to their novel properties and great potential application in spin electronics. It is more challenging to find 2D nodal-line semimetals that can resist the spin–orbit coupling(SOC)effect. Here, we predict that 2D tetragonal Zn B is a nodal-line semimetal with great transport properties. There are two crossing bands centered on the S point at the Fermi surface without SOC, which are mainly composed of the pxy orbitals of Zn and B atoms and the pz orbitals of the B atom. Therefore, the system presents a nodal line centered on the S point in its Brillouin zone(BZ). And the nodal line is protected by the horizontal mirror symmetry M_(z). We further examine the robustness of a nodal line under biaxial strain by applying up to-4% in-plane compressive strain and 5% tensile strain on the Zn B monolayer, respectively. The transmission along the a direction is significantly stronger than that along the b direction in the conductive channel. The current in the a direction is as high as 26.63 μA at 0.8 V, and that in the b direction reaches 8.68 μA at 0.8 V. It is interesting that the transport characteristics of Zn B show the negative differential resistance(NDR) effect after 0.8 V along the a(b) direction. The results provide an ideal platform for research of fundamental physics of 2D nodal-line fermions and nanoscale spintronics, as well as the design of new quantum devices.展开更多
The quantum anomalous Hall(QAH) effect has attracted enormous attention since it can induce topologically protected conducting edge states in an intrinsic insulating material. For practical quantum applications, the m...The quantum anomalous Hall(QAH) effect has attracted enormous attention since it can induce topologically protected conducting edge states in an intrinsic insulating material. For practical quantum applications, the main obstacle is the non-existent room temperature QAH systems, especially with both large topological band gap and robust ferromagnetic order. Here, according to first-principles calculations, we predict the realization of the room temperature QAH effect in a two-dimensional(2D) honeycomb lattice, RuCS_(3) with a non-zero Chern number of C = 1. Especially, the nontrivial topology band gap reaches up to 336 me V for RuCS_(3). Moreover, we find that RuCS_(3) has a large magnetic anisotropy energy(2.065 me V) and high Curie temperature(696 K). We further find that the non-trivial topological properties are robust against the biaxial strain. The robust topological and magnetic properties make RuCS_(3) have great applications in room temperature spintronics and nanoelectronics.展开更多
基金financially supported by National Natural Science Foundation of China(grant Nos.22071020,22171041,22271043,22205034)Natural Science Foundation of Jilin Province Science and Technology Department(grant No.20220101045JC)the Fundamental Research Funds for the Central Universities(grant Nos.2412021QD008,2412022QD012).
文摘Although crystalline anode materials with long-range ordered lattice structure are in favor of facilitating the electron transfer,their structures are easily disrupted during long-term cycling due to the continuous embedding/de-embedding of lithium ions.In contrast,the amorphous materials have abundant defects and lithium ion storage sites,refl ecting a superior reaction kinetics and long-term cycling stability.Here,we synthesize an integrated hybrid anode by in-situ loading amorphous NiMo_(3)S_(13)nanosheets on nickel foam substrate.Benefi ting from the introduction of Ni^(2+)that amorphizes the molybdenumsulfur clusters,the assembled lithium ion battery based on the integrated NiMo_(3)S_(13)/nickel foam anode delivers a specifi c capacity up to 1659 mA·h·g^(−1)at a current density of 0.6 A·g^(−1)and exhibits superior rate/cycling performance.
基金Scientific Research Project of Military Logistics Department,Grant Award Number:CLB20J032。
文摘Background:Until January 18,2021,coronavirus disease-2019(COVID-19)has infected more than 93 million individuals and has caused a certain degree of panic.Viral pneumonia caused by common viruses such as respiratory syncytial virus,rhinovirus,human metapneumovirus,human bocavirus,and parainfluenza viruses have been more common in children.However,the incidence of COVID-19 in children was significantly lower than that in adults.The purpose of this study was to describe the clinical manifestations,treatment and outcomes of COVID-19 in children compared with those of other sources of viral pneumonia diagnosed during the COVID-19 outbreak.Methods:Children with COVID-19 and viral pneumonia admitted to 20 hospitals were enrolled in this retrospective multi-center cohort study.A total of 64 children with COVID-19 were defined as the COVID-19 cohort,of which 40 children who developed pneumonia were defined as the COVID-19 pneumonia cohort.Another 284 children with pneumonia caused by other viruses were defined as the viral pneumonia cohort.The epidemiologic,clinical,and laboratory findings were compared by Kolmogorov-Smirnov test,t-test,Mann-Whitney U test and Contingency table method.Drug usage,immunotherapy,blood transfusion,and need for oxygen support were collected as the treatment indexes.Mortality,intensive care needs and symptomatic duration were collected as the outcome indicators.Results:Compared with the viral pneumonia cohort,children in the COVID-19 cohort were mostly exposed to family members confirmed to have COVID-19(53/64 vs.23/284),were of older median age(6.3 years vs.3.2 years),and had a higher proportion of ground-glass opacity(GGO)on computed tomography(18/40 vs.0/38,P<0.001).Children in the COVID-19 pneumonia cohort had a lower proportion of severe cases(1/40 vs.38/284,P=0.048),and lower cases with high fever(3/40 vs.167/284,P<0.001),requiring intensive care(1/40 vs.32/284,P<0.047)and with shorter symptomatic duration(median 5d vs.8d,P<0.001).The proportion of cases with evaluated inflammatory indica
基金supported by the National Key Research and Development Program of China(Grant No.2017YFA0304800)the National Natural Science Foundation of China(Grant Nos.61525504,61722510,61435011,11174271,61275115,and 11604322)+1 种基金the Anhui Initiative in Quantum Information Technologies(Grant No.AHY020200)the Youth Innovation Pro motion Association of Chinese Academy of Sciences(Grant No.2018490)。
文摘The long-range interaction between Rydberg-excited atoms endows a medium with large optical nonlinearity.Here,we demonstrate an optical switch to operate on a single photon from an entangled photon pair under a Rydberg electromagnetically induced transparency configuration.With the presence of the Rydberg blockade effect,we switch on a gate field to make the atomic medium nontransparent thereby absorbing the single photon emitted from another atomic ensemble via the spontaneous fourwave mixing process.In contrast to the case without a gate field,more than 50%of the photons sent to the switch are blocked,and finally achieve an effective single-photon switch.There are on average 1-2 gate photons per effective blockade sphere in one gate pulse.This switching effect on a single entangled photon depends on the principal quantum number and the photon number of the gate field.Our experimental progress is significant in the quantum information process especially in controlling the interaction between Rydberg atoms and entangled photon pairs.
基金Project supported by the Natural Science Foundation of Shandong Province, China (Grant No. ZR2019MA041)Taishan Scholar Project of Shandong Province, China (Grant No. ts20190939)the National Natural Science Foundation of China (Grant No. 62071200)。
文摘Nodal-line semimetals have become a research hot-spot due to their novel properties and great potential application in spin electronics. It is more challenging to find 2D nodal-line semimetals that can resist the spin–orbit coupling(SOC)effect. Here, we predict that 2D tetragonal Zn B is a nodal-line semimetal with great transport properties. There are two crossing bands centered on the S point at the Fermi surface without SOC, which are mainly composed of the pxy orbitals of Zn and B atoms and the pz orbitals of the B atom. Therefore, the system presents a nodal line centered on the S point in its Brillouin zone(BZ). And the nodal line is protected by the horizontal mirror symmetry M_(z). We further examine the robustness of a nodal line under biaxial strain by applying up to-4% in-plane compressive strain and 5% tensile strain on the Zn B monolayer, respectively. The transmission along the a direction is significantly stronger than that along the b direction in the conductive channel. The current in the a direction is as high as 26.63 μA at 0.8 V, and that in the b direction reaches 8.68 μA at 0.8 V. It is interesting that the transport characteristics of Zn B show the negative differential resistance(NDR) effect after 0.8 V along the a(b) direction. The results provide an ideal platform for research of fundamental physics of 2D nodal-line fermions and nanoscale spintronics, as well as the design of new quantum devices.
基金the Natural Science Foundation of Shandong Province, China (Grant No. ZR2019MA041)the Taishan Scholar Project of Shandong Province, China (Grant No. ts20190939)+1 种基金the National Natural Science Foundation of China (Grant No. 62071200)the Shandong Provincial Natural Science Foundation, China (Grant No. ZR2020QA052)。
文摘The quantum anomalous Hall(QAH) effect has attracted enormous attention since it can induce topologically protected conducting edge states in an intrinsic insulating material. For practical quantum applications, the main obstacle is the non-existent room temperature QAH systems, especially with both large topological band gap and robust ferromagnetic order. Here, according to first-principles calculations, we predict the realization of the room temperature QAH effect in a two-dimensional(2D) honeycomb lattice, RuCS_(3) with a non-zero Chern number of C = 1. Especially, the nontrivial topology band gap reaches up to 336 me V for RuCS_(3). Moreover, we find that RuCS_(3) has a large magnetic anisotropy energy(2.065 me V) and high Curie temperature(696 K). We further find that the non-trivial topological properties are robust against the biaxial strain. The robust topological and magnetic properties make RuCS_(3) have great applications in room temperature spintronics and nanoelectronics.
