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Ab initio prediction and characterization of phosphorene-like SiS and SiSe as anode materials for sodium-ion batteries

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Science Bulletin 2017年第8期62卷 572-578页

作者： Haoran Jiang Tianshou Zhao Yuxun Ren Ruihan Zhang maochun wu Department of Mechanicol and Aerospace Engineering The Hong Kong University of Science and Technology Hong Kong. Chino

In this work, a density functional theory(DFT) based first-principles study is carried out to investigate the potential of phosphorene-like SiS and SiSe monolayers as anode materials for sodium-ion(Na-ion) batteries. Results show that both SiS and SiSe have large adsorption energies towards single Na atom of 0.94 and 0.43 eV, owing to the charge transfers from Na to SiS or SiSe. In addition, it is found that the highest Na concentration for both SiS and SiSe is x = 1 with the chemical formulas of Na SiS and Na SiSe, corresponding to the high theoretical specific capacities for Na storages of 445.6 and 250.4 m Ah g^(-1), respectively. Moreover, Na diffusions are very fast and show strong directional behaviors on SiS and SiSe monolayers, with the energy barriers of only 0.135 and 0.158 eV, lower than those of conventional anode materials for Na-ion batteries such as Na_2Ti_3O_7(0.19 eV) and Na_3Sb(0.21 eV). Finally,although SiS and SiSe show semiconducting behaviors, they transform to metallic states after adsorbing Na atoms, indicating enhanced electrical conductivity during battery cycling. Given these advantages, it is expected that both SiS and SiSe monolayers are promising anode materials for Na-ion batteries, and in principle, other Na-based batteries as well.

关键词：钠离子电池正极材料 SIS 从头预测 Na原子第一性原理表征密度泛函理论

A Li-S battery with ultrahigh cycling stability and enhanced rate capability based on novel ZnO yolk-shell sulfur host

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Journal of Energy Chemistry 2021年第4期30卷 136-144页

作者： Ruihan Zhang maochun wu Xinzhuang Fan Haoran Jiang Tianshou Zhao Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina

Currently,lithium-sulfur(Li-S)batteries still suffer from fast capacity decay,poor coulombic efficiency(CE)and short cycling lifespan,which result from the severe shuttle effect issue caused by high solubility and rapid diffusion of lithium polysulfides(Li PSs)in organic ***,yolk-shell zinc oxide(YSZn O)spheres are synthesized and for the first time,applied as a host for Li-S batteries to tackle this *** polar Zn O exhibits high chemical anchoring ability toward Li PSs while the unique yolk-shell structure not only provides an additional physical barrier to Li PSs but also enables much more uniform sulfur distribution,thus significantly suppressing Li PSs shuttling effect meanwhile promoting sulfur conversion *** a result,the YS-Zn O enables the Li-S battery to display an initial specific capacity of1355 m Ah g^(-1) and an outstanding capacity retention capability(~89.44%retention rate)even after 500 cycles with the average CE of~99.46%at the current of 0.5 *** contrast,the capacity of conventional-Zn O-nanoparticles based battery severely decays to 472 m Ah g^(-1) after cycling for 500 *** impressively,the S/YS-Zn O based Li-S battery can maintain a low decay rate of 0.040%every cycle and high average CE of 98.82%over 1000 cycles at 3 C.

关键词： Yolk-shell structure Lithium-sulfur batteries Zinc oxide Shuttle effect In-situ Raman test

Numerical simulation of hot accretion flows with thermal conduction

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Science China(Physics,Mechanics & Astronomy) 2010年第S1期53卷 168-172页

作者： wu maochun,YUAN Feng & BU DeFu Key Laboratory for Research in Galaxies and Cosmology,Shanghai Astronomical Observatory,Chinese Academy of Sciences,Shanghai 200030,China Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences

We report on the effects of isotropic thermal conduction in non-radiative collisionless accretion flows in two *** comparison to accretion flows without conduction,we find that the disk generally becomes cooler and ***,the magnitude of this effect depends on the kinetic viscosity *** it is proportional to density,the density profile of the accretion flow is flat,therefore the effect is not very ***,if it is proportional to r1/2,as is usual for the "α" disk description,the density profile is ***,the effect will be much more obvious,with the temperature profile of the accretion flow becoming much *** will have important observational consequences.

关键词： black hole accretion disk thermal conduction

On the effect of injection of gas in the numerical simulation of accretion flows

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Science China(Physics,Mechanics & Astronomy) 2010年第S1期53卷 139-142页

作者： BU DeFu,YUAN Feng,wu maochun & YANG XiaoHong Key Laboratory for Research in Galaxies and Cosmology,Shanghai Astronomical Observatory,Chinese Academy of Sciences,Shanghai 200030,China Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences

We investigate the effects of various ways of injection of gas at the outer boundary in the numerical simulations of non-viscous accretion *** study three *** Model A,we inject material around the equatorial *** Models B and C,fullrange θ injection is used(we employ spherical coordinates).In all three models,the injected material has the same density distribution with polar angle θ.From the equatorial region to the polar regions,angular momentum of the injected material of Model B decreases faster than that in Model *** all of the models,after a transient episode of infall at the beginning of the simulations,the gas piles up in the equatorial regions outside the black hole and forms a thick torus bounded by a centrifugal *** find that the accretion rates of Models B and C are more than ten times higher than that in Model *** Model A,there is weak accretion only in the torus and outflows are found on the surface of the *** Model B,we find strong inflows on the surface of its torus,and the accretion in the torus is *** Model C,strong inflows also occur on the surface of its torus,but the accretion regions are narrower and there are strong outflows in its *** all of our models,the time-averaged density,pressure and angular momentum in the equatorial region can be described by a radial power law,with P ∝r-3/2,P ∝r-2 and l∝r0.

关键词： accretion accretion discs-black hole physics-hydrodynamics numerical

甲状腺肿瘤患者生化免疫检验中应用化学发光免疫检验法技术的诊断价值

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中国医药指南 2023年第28期21卷 47-50页

作者：吴茂春刘敏赣州市会昌县人民医院江西会昌342600

目的观察甲状腺肿瘤患者生化免疫检验中应用化学发光免疫检验法技术的临床诊断价值。方法以我院就诊的甲状腺肿瘤患者94例为研究对象,研究起止时间2021年11月至2022年12月,所有患者均采用放射性免疫检验法技术检验、化学发光免疫检验... 详细信息

目的观察甲状腺肿瘤患者生化免疫检验中应用化学发光免疫检验法技术的临床诊断价值。方法以我院就诊的甲状腺肿瘤患者94例为研究对象,研究起止时间2021年11月至2022年12月,所有患者均采用放射性免疫检验法技术检验、化学发光免疫检验法技术检验,观察两种方式甲状腺功能检查结果的差异。结果放射性免疫检验法、化学发光免疫检验法抗甲状腺过氧化物酶抗体(TPOAB)、抗甲状腺球蛋白抗体(TGAB)水平比较差异无统计学意义(P>0.05);化学发光免疫检验法甲状腺激素(TSH)、游离三碘甲状腺原氨酸(FT_3)、游离四碘甲状腺原氨酸(FT_4)水平高于放射性免疫检验法检验水平,差异有统计学意义(P<0.05)。化学发光免疫检验法甲状腺功能异常检出率高于放射性免疫检验法,差异有统计学意义(P<0.05)。化学发光免疫检验法对于甲状腺肿瘤的诊断准确度、灵敏度及特异度均较放射性免疫检验法高(P<0.05)。结论在甲状腺肿瘤生化检验中可以采用化学发光免疫检验法技术,分析患者甲状腺功能相关指标水平,甲状腺功能异常检出率、诊断准确度、灵敏度及特异度较高。

关键词：甲状腺功能化学发光免疫检验法甲状腺肿瘤生化免疫检验诊断价值

V2O5-NiO composite nanowires:a novel and highly efficient carbon-free electrode for non-aqueous Li-air batteries operated in ambient air

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V2O5-NiO composite nanowires:a novel and highly efficient ca...

中国化学会第三届中国能源材料化学研讨会

作者： Ruihan Zhang Haoran Jiang maochun wu Lin Zeng Tianshou Zhao HKUST Energy Institute Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and Technology

Due to the ultra-high theoretical specific capacity and energy density,the non-aqueous Li-air battery has attracted a lot of attention over the past ***,the decomposition of electrode during discharge and charge processes has seriously limited the further development of this ***,we fabricate a novel carbonand binder-free electrode,VO-NiO composite nanowires,via a hydrothermal method associated with a sintering *** this novel electrode,the battery displays an over-potential of as low as 0.56 V and is operated stably for 250 cycles(1000 h) with an energy efficiency of as high as 70% at the current of 250 mA g with a fixed capacity of 500 mAh g in pure *** the current density further increases from 250 to 500 and 750 mA g,the electrode enables the battery to operate stably for 220 and 200 cycles,indicating the excellent cycling stability and rate capability of the VO-NiO composite nanowire in pure ***,in ambient air,the battery with this electrode can still be steadily cycled for as high as 200 times(800 h) at the current density of 250 mA g with a coulombic efficiency of 100% and an energy efficiency of as high as ～68%.Therefore,the VO-NiO composite nanowire offers great promise to replace the carbon electrode and further realize the operation of the truly nonaqueous Li-air battery in ambient air.

关键词：

来源： cnki会议评论

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Ⅳ型分泌系统及其对细菌重金属抗性的影响

微生物学通报 2024年第5期51卷 1460-1470页

作者：伍燕梅岳彦博罗茂春鲁小璐中国地质大学(武汉)环境学院湖北武汉430074

Ⅳ型分泌系统(typeⅣsecretion system,T4SS)是广泛存在于细菌中的特殊蛋白分泌系统,不同于其他分泌系统,该系统不仅能够转运蛋白质,还能转移DNA、DNA-蛋白质复合物。因此,T4SS具有多种生物学特性。T4SS能介导细菌的接合作用,而接合是... 详细信息

Ⅳ型分泌系统(typeⅣsecretion system,T4SS)是广泛存在于细菌中的特殊蛋白分泌系统,不同于其他分泌系统,该系统不仅能够转运蛋白质,还能转移DNA、DNA-蛋白质复合物。因此,T4SS具有多种生物学特性。T4SS能介导细菌的接合作用,而接合是水平基因转移(horizontal gene transfer,HGT)的重要机制之一,细菌能够利用T4SS介导的接合作用转移大部分可移动基因元件(mobile genetic element,MGE),如接合型质粒和整合性元件,从而使细菌获得新的基因,这些辅助基因在特定环境条件下有益于帮助细菌获得新功能,有助于细菌在新环境中占据生态位,极大地促进了细菌对环境条件变化的适应性。本文主要对细菌T4SS的生物学作用研究进展进行综述,并探讨了T4SS在细菌适应重金属环境中的作用。

关键词：细菌 Ⅳ型分泌系统水平基因转移重金属抗性

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城市再生水系统优化研究

环境与发展 2018年第2期30卷 233-234页

作者：伍茂春四川城市职业学院四川成都610101

面临城市水资源危机、水体污染的现实情况,当前缓解的有效途径之一便是污水再生利用。我国城市再生水开发利用发展较快,但有关再生水系统的优化配置、规划布局都存在很大不足,造成再生水利用率较低,产生更加恶劣的影响。本文通过分析城... 详细信息

面临城市水资源危机、水体污染的现实情况,当前缓解的有效途径之一便是污水再生利用。我国城市再生水开发利用发展较快,但有关再生水系统的优化配置、规划布局都存在很大不足,造成再生水利用率较低,产生更加恶劣的影响。本文通过分析城市再生水系统的作用,探讨其影响因素;之后从集中式和分散式探讨城市再生水供水模式,通过对某城市居住小区再生水系统的优化研究,以该城市再生水系统的优化成果进行分析,探讨该优化系统的可行性。

关键词：再生水系统管网供水效率优化配置

A Cage-based Porous Metal-Organic Framework for Efficient C_(2)H_(2) Storage and Separation

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Chemical Research in Chinese Universities 2022年第1期38卷 82-86页

作者： LI Hengbo WANG Kuikui wu Mingyan HONG maochun College of Chemistry Fuzhou UniversityFuzhou 350108P.R.China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002P.R.China

Exploring the application potentials of metal-organic frameworks(MOFs) in the field of light hydrocarbons storage and separation is of great significance for solving the critical energy problem. However, designing porous materials with efficient separation capacity is still a challenging task. In this work, we synthesized a cage-based porous materiel(FJI-H32) with a large surface area. After activation, FJI-H32 exhibits the feature of high C2H2 storage capacity(113 cm3/g) and promising C2H2/CO_(2) separation ability at 298 K and under 100 kPa. More importantly, the CO_(2) separation was verified by actual breakthrough experiments.

关键词： Metal-organic framework Light hydrocarbon Storage and separation Molecular cage Breakthrough experiment