Boron-doped high-entropy oxide toward high-rate and long-cycle layered cathodes for wide-temperature sodium-ion batteries

03-type layered metal oxides hold great promise for sodium-ion batteries cathodes owing to their energy density advantage.However,the severe irreversible phase transition and sluggish Na^(+)diffusion kinetics pose significant challenges to achieve high-performance layered cathodes.Herein,a boron-doped03-type high entropy oxide Na(Fe_(0.2)Co_(0.15)Cu_(0.05)Ni_(0.2)Mn_(0.2)Ti_(0.2))B_(0.02)O_(2)(NFCCNMT-B_(0.02))is designed and the covalent B-O bonds with high entropy configuration ensure a robust layered structure.The obtained cathode NFCCNMT-B_(0.02)exhibits impressive cycling performance(capacity retention of 95%and 82%after100 cycles and 300 cycles at 1 and 10 C,respectively)and outstanding rate capability(capacity of 83 mAh g^(-1)at 10 C).Furthermore,the NFCCNMT-B_(0.02)demonstrates a superior wide-temperature performance,maintaining the same capacity level(113,4 mAh g^(-1)@-20℃,121 mAh g^(-1)@25℃,and 119 mAh g^(-1)@60℃)and superior cycle stability(90%capacity retention after 100 cycles at 1 C at-20℃).The high-entropy configuration design with boron doping strategy contributes to the excellent sodium-ion storage performance.The high-entropy configuration design effectively suppresses irreversible phase transitions accompanied by small volume changes(ΔV=0.65 A3).B ions doping expands the Na layer distance and enlarges the P3 phase region,thereby enhancing Na^(+)diffusion kinetics.This work offers valuable insights into design of high-performance layered cathodes for sodium-ion batteries operating across a wide temperature.

Some Notable Chinese in Dublin in the Mid-Twentieth Century

The careers of three Chinese physicists,Hu Ning,Ma Shijun,and Peng Huanwu at the Dublin Institute for Advance Studies in the 1940s,and later,are described.A brief history of the foundation and operations of the institute,as well as the roles in it of Erwin Schrodinger,Walter Heitler,Max Born,and others are included.Some details are given of the works carried out there.The three men's post-institute careers are described,Ma eventually in Australia,and Hu and Peng in the People's Republic of China where they became distinguished leaders of theoretical physics research.

障碍干扰下的压缩感知电磁成像算法

基于电磁成像模型,针对逆散射问题的病态性和非线性性质,引入压缩感知(CS)中的全变分(TV)算法,旨在减少所需天线数量,并提高电磁成像的图像质量.在玻恩(Born)迭代的基础上,引入全变分压缩感知算法(TV-CS).仿真结果显示:即使目标被障碍物遮挡,该算法也能够在配置较少探测天线的情况下,对目标位置和形状进行准确的重构.

A Legend Story about Zhuhai

My English name is Tina.I am a pupil from No.2 Experimental Primary School of Doumen,Zhuhai.I was born in Zhuhai,a beautiful city.The Riyue Opera House is a famous scenic spot in Zhuhai.It is composed of two huge shell-shaped buildings that look like pearls in the sea,shining with brilliant light.This is not only the best place to enjoy the sea view but also a cultural space full of art.

瞬变电磁虚拟波场层状Green函数Born近似成像方法

瞬变电磁虚拟波场Born近似成像是通过Born近似对瞬变电磁虚拟波场方程进行线性化处理,求取速度扰动量实现成像的方法.Born近似采用半空间Green函数,在背景速度变化较大时成像分辨率较低.因此,本文从虚拟波场出发,建立辐射场与散射场满足的Helmholtz方程,导出层状介质Green函数表达式,将其应用于Born近似中,得到了基于层状介质格林函数的Born近似电导率计算公式和散射场关于速度扰动量的关系式,最终利用速度扰动量实现成像.通过对理论模型的实验计算,验证了利用层状模型Green函数的Born近似成像算法,能够重建地层电阻率分布,改善Born近似虚拟波动方程逆散射反演的垂向分辨率,获得较好的成像效果.对甘肃地区的实际资料处理结果表明,层状介质Green函数的Born近似,是一个精确度较高、稳定性好、有实际应用价值的成像方法.

基于逆散射成像条件的转换波弹性波动方程自动偏移速度分析

在地震偏移成像过程中,成像精度依赖于速度模型,因此偏移速度分析对高精度叠前偏移成像至关重要。基于高频近似下的逆散射成像条件,提出了基于剩余曲率分析的转换波弹性波动方程偏移速度分析方法。首先基于高频近似下的逆散射成像条件,采用逆时偏移近似估计转换S波散射位,然后结合入射P波和转换S波散射位,重构得到上行转换S波,最后利用伴随状态法导出剩余时差关于波速的梯度。基于逆散射成像条件,有效保证了弹性波动方程偏移速度分析中梯度的稳定求解。数值实验表明该方法导出了高质量的梯度。初步测试表明反演的速度模型有效地校平了共成像点道集,改善了成像质量。此外,剩余时差曲率智能识别等技术简化了中间处理流程,构建的智能化速度分析框架有望提升计算效率。

微分算子展开与耦合势三维有限体积法快速计算随钻超深前视电阻率测井响应非线性Born逼近

本文将非均质各向异性地层中电磁场耦合势Helmhotz方程分解为各向异性背景场方程与散射场方程,并应用算子展开技术推导出耦合势Born级数解,建立一套三维非均质各向异性地层中随钻超深前视电阻率测井响应各阶散射电磁场与非线性Born逼近的有效计算方法.首先,利用传输线法与二维插值技术确定背景电磁场空间分布,得到零阶Born逼近解,然后根据电磁场耦合势的Born级数解推导出各阶散射电磁场方程与递推关系,通过三维有限体积法实现各阶散射场耦合势方程的离散,在此基础上结合MKL PARDISO并行技术,通过递推方式逐步计算各阶散射电磁场,并根据Born级数部分和确定不同阶次的非线性Born逼近.最后利用数值模拟结果对正演算法加以检验,并深入研究分析各阶散射场的变化特征与Born级数的收敛性质.

An effective method to calculate the electron impact excitation cross sections of helium from ground state to a final channel in the whole energy region

The electron impact excitation(EIE) cross sections of an atom/ion in the whole energy region are needed in many research fields, such as astrophysics studies, inertial confinement fusion researches and so on. In the present work, an effective method to calculate the EIE cross sections of an atom/ion in the whole energy region is presented. We use the EIE cross sections of helium as an illustration example. The optical forbidden 1^(1)S–n^(1)S(n = 2–4) and optical allowed 1^(1)S–n^(1)P(n = 2–4) excitation cross sections are calculated in the whole energy region using the scheme that combines the partial wave R-matrix method and the first Born approximation. The calculated cross sections are in good agreement with the available experimental measurements. Based on these accurate cross sections of our calculation, we find that the ratios between the accurate cross sections and Born cross sections are nearly the same for different excitation final states in the same channel. According to this interesting property, a universal correction function is proposed and given to calculate the accurate EIE cross sections with the same computational efforts of the widely used Born cross sections,which should be very useful in the related application fields. The datasets presented in this paper are openly available at https://www.doi.org/10.57760/sciencedb.j00113.00142.

电性源瞬变电磁Born近似反演及其在煤田采空区探测中的应用

以电性源瞬变电磁装置为研究对象,在虚拟波场条件下基于Born近似反演实现煤田采空区探测,探测结果既能够获得地层的连续起伏与错断的形态、定位采空区的位置,又能够获得地下空间的电性分布特征,从而实现定性与定量解释。通过采空区理论模型计算,可以获得采空区的边界、煤层的埋深,与地层的电性分布;通过对实测数据的处理,结果表明可以有效地提供含水采空区的位置、地层的形态以及地下的电性分布特征,与煤层地质信息的对比可知,基于电性源瞬变电磁Born近似反演解释方法可以准确得到煤层开挖后含水采空区电性分布、边界信息以及几何特征。

Research progress and prospects of arenavirus

Arenaviruses belong to the family of RNA viruses that can infect humans in various ways and cause different degrees of mortality.Rodents is the mainly hosts.Human pathogenic arenaviruses include lymphocytic choroid meningitis,Lassa virus group and Takarib virus group,which cause human lymphocytic choriomeningitis and human hemorrhagic diseases.Rodents account for about 43%of mammalian species.At present,more than 30 highly pathogenic viruses have been found in rodents,including arenaviruses.The arenaviridae that infects rodents are mainly mammalian arenaviruses.This article reviews the etiology,clinicopathology,epidemiology,prevention and control of arenavirus,and provides references for the research and prevention of arenavirus.

Exploring unbinding mechanism of drugs from SERT via molecular dynamics simulation and its implication in antidepressants

The human serotonin transporter(SERT)terminates neurotransmission by removing serotonin from the synaptic cleft,which is an essential process that plays an important role in depression.In addition to natural substrate serotonin,SERT is also the target of the abused drug cocaine and,clinically used antidepressants,escitalopram,and paroxetine.To date,few studies have attempted to investigate the unbinding mechanism underlying the orthosteric and allosteric modulation of SERT.In this article,the conserved property of the orthosteric and allosteric sites(S1 and S2)of SERT was revealed by combining the high resolutions of x-ray crystal structures and molecular dynamics(MD)simulations.The residues Tyr95 and Ser438 located within the S1 site,and Arg104 located within the S2 site in SERT illustrate conserved interactions(hydrogen bonds and hydrophobic interactions),as responses to selective serotonin reuptake inhibitors.Van der Waals interactions were keys to designing effective drugs inhibiting SERT and further,electrostatic interactions highlighted escitalopram as a potent antidepressant.We found that cocaine,escitalopram,and paroxetine,whether the S1 site or the S2 site,were more competitive.According to this potential of mean force(PMF)simulations,the new insights reveal the principles of competitive inhibitors that lengths of trails from central SERT to an opening were~18A for serotonin and~22 A for the above-mentioned three drugs.Furthermore,the distance between the natural substrate serotonin and cocaine(or escitalopram)at the allosteric site was~3A.Thus,it can be inferred that the potent antidepressants tended to bind at deeper positions of the S1 or the S2 site of SERT in comparison to the substrate.Continuing exploring the processes of unbinding four ligands against the two target pockets of SERT,this study observed a broad pathway in which serotonin,cocaine,escitalopram(at the S1 site),and paroxetine all were pulled out to an opening between MT1b and MT6a,which may be helpful to understand the dissociation mechanism of antidepressants.

Detection, Biochemical and Molecular Characterization of Clostridium sporogens in Nono: A Nigerian Traditionally Fermented Yoghurt Drink

Nono is a traditionally fermented milk drink commonly consumed in the Northern parts of Nigeria. It is produced through the spontaneous fermentation of raw cow milk by Lactic Acid Bacteria (LAB), a process that could result to the contamination of the product with such pathogenic organisms as Clostridia spp. The aim of this research was therefore to determine the incidence of Clostridia species in thirty-two (32) ready-to-drink nono samples collected directly from a number of Fulani vendors in randomly selected locations within the Federal Capital Territory (FCT), Abuja, Nigeria. Isolated organisms were further subjected to some morphological and biochemical characterizations using standard microbiological procedures. The results obtained indicate that fourteen (14) isolates were putatively identified to be Clostridium sp., out of which five (5) isolates were confirmed to be Clostridium sporogens by a BLAST analysis of their respective 16SrRNA nucleotide sequence. It was concluded that, the detection of these pathogenic strains in frequently consumed product like nono could pose a public health risk and proactive measures to prevent an outbreak of food borne illness from nono consumption, were recommended.

Assessing the Role of Environmental Factors in the Transmission of Infectious Diseases in Communal Spaces

Communal spaces provide different facilities for users while they are the primary place for the spread of diseases,especially respiratory.Transmission is possible through human behaviors,the way they communicate with each other and breathe in an environment by airborne pathogenic particles.Experts from various fields have gained valuable experience and achievements regarding how to prevent these diseases by means of environmental factors.Due to the spread of the corona virus in the past years,environmental planners and designers seriously considered the need to review the design and use of spatial components.This study provides a framework for decision making and design of communal spaces based on how environmental components can be effective in preventing the spread of respiratory diseases such as coronavirus and influenza.The research method used in this article is logical reasoning combined with ANP method and focus group discussion.According to the results of this research,indoor air quality plays the most crucial role in preventing the transmission of viruses(contagious respiratory diseases)based on expert groups.

Investigation of Electronic, Elastic and Dynamic Properties of AgNbO3 and AgTaO3 under Pressure: Ab Initio Calculation

Based on the density functional theory within the local density approximation (LDA), we studied the electronic, elastic, and dynamic properties of AgNbO3 and AgTaO3 compounds under pressure. The elastic constants, optic and static dielectric constants, born effective charges, and dynamic properties of AgNbO3 and AgTaO3 in cubic phase were studied as pressure dependences with the ab initio method. For these compounds, we have also calculated the bulk modulus, Young’s modulus, shear modulus, Vickers hardness, Poisson’s ratio, anisotropy factor, sound velocities, and Debye temperature from the obtained elastic constants. In addition, the brittleness and ductility properties of these compounds were estimated from Poisson’s ratio and Pugh’s rule (G/B). Our calculated values also show that AgNbO3 (0.37) and AgTaO3 (0.39) behave as ductile materials and steer away from brittleness by increasing pressure. The calculated values of Vicker hardness for both compounds indicate that they are soft materials. The results show that band gaps, elastic constants, elastic modules, and dynamic properties for both compounds are sensitive to pressure changes. We have also made some comparisons with related experimental and theoretical data that is available in the literature.

初至波菲涅尔体地震层析成像

根据地震波传播的有限频理论,对于某个特定震相的观测信息,不仅射线路径上的点对该信息具有影响,射线领域上的其他点对接收信息也具有影响,这种影响可以用核函数来表达.本文基于波动方程的Born近似与Rytov近似,给出了非均匀介质情况下初至地震波振幅与走时菲涅尔体层析成像单频、带限层析核函数的计算方法.通过对均匀介质情况下初至地震波菲涅尔体层析成像核函数解析表达式的理论模型实验与分析,给出了不同维度振幅、走时单频菲涅尔体的空间分布范围,进而给出了带限菲涅尔体边界的确定方法.将本文的走时非涅尔体层析成像理论应用于表层速度结构反演中,理论模型试验与实际资料处理结果表明,初至波菲涅尔体地震层析成像方法比传统的初至波射线层析成像理沦具有更高的反演精度.

地震波反演成像方法与技术核心问题分析

常规的地震反演成像分为偏移速度分析与层析成像、叠前深度偏移(角度道集产生)和AVA分析/反演3个重要环节,其中的关键技术是当前勘探地震学中的核心技术。全波形反演(FWI)是理论意义下十分完善的地震波反演成像理论框架。原则上,FWI可以把上述3项常规的反演方法技术合为一体,给出比较理想的反演成像结果。但是,由于叠前地震数据的不完备、地震波正演模拟方法不能很好地模拟实测地震波场、初始模型不够精确、地震子波的未知和空变,使得严格意义下的FWI方法尚不能很好地解决实际问题。通过叠前地震数据和地下介质模型的特征表达,提出把经典的FWI分成透射波层析成像、最小二乘叠前深度偏移成像和反射波层析成像3个线性化反演方法的串联,构成FWI反演成像的实用化流程。针对我国陆上地震数据的特点,指出做好浅层速度模型建立、背景速度模型建立、成像道集层析速度模型建立、最小二乘叠前深度偏移成像、张角及界面倾角道集的产生以及小角度成像道集波阻抗反演,是当前推进FWI反演成像方法技术应用与发展的关键所在。

基于Born波路径的高斯束初至波波形反演

为了提高表层速度反演精度,本文提出了一种新的波形反演方法.该方法只利用初至波波形信息以减少波形反演对初始模型的依赖性,降低反演多解性与稳定性.由于只利用初至波波形信息,所以该方法利用高斯束计算格林函数和正演波场,以减少正演计算量.为了避免庞大核函数的存储,该方法基于Born波路径,利用矩阵分解算法实现方向与步长的累加计算.将此基于Born波路径的初至波波形反演方法应用于理论模型实验,并与声波方程全波形反演和初至波射线走时层析方法相对比,发现该方法的反演效果略低于全波形反演方法,但明显优于传统初至波射线走时层析方法,而计算效率却与射线走时层析相当.同时,相对于全波形反演,本文方法对初始模型的依赖性也有所降低.

稳定的Born近似叠前深度偏移方法

本文针对 Huang L J等 (1999)在“扩展的局部 Born Fourier偏移方法”一文中提出的散射波场计算公式对于强横向变速介质的不稳定性 ,提出了一种新的 Born近似散射场计算公式 ,并把该公式应用于波场递归外推过程中 ,进而得到一种稳定的 Born近似叠前深度偏移方法。与 Split- StepFourier方法和 Phase- Screen方法相比 ,本方法对 Marmousi模型炮集数据的偏移处理取得了良好的结果。本文提出的 Born近似散射场计算公式可扩大 Born近似的应用范围 ,对散射波场的计算有一定的理论意义和应用价值。

井间电磁成像的迭代反演算法

提出一种基于逐次逼近解法的选代反演算法，对并间地层电导率的构造进行成像．该方法用一阶Ｂｏｒｎ近似将积分方程线性化，得到对电导率分布的初始估计，在选代反演中用高阶Ｂｏｒｎ近似对井间地层电导率构造进行更精确的估计．应用该方法还可以对井间电子率分布进行二次成像，从而使成像分辨率更为准确．数值计算结果表明，这种迭代反演算法与基于Ｂｏｒｎ近似、二阶Ｂｏｒｎ近似和扩展Ｂｏｒｎ近似的反演算法相比提高了成像分辨率，且计算效率相当．

波阻抗反演在琼东南海域水合物检测中的应用

为了更好地研究天然气水合物的展布形态和赋存情况,对琼东南海域天然气水合物勘探区的地震资料进行波阻抗反演。首先利用基于精细速度分析的高分辨率层速度反演方法来建立低频阻抗模型,然后采用了基于波动方程Born近似的直接反演和基于模型优化的间接反演两种方法进行反演研究。结果表明,研究区数据体波阻抗高低分异明显,地质现象比较清楚,能够比较准确地反映地下水合物矿体的展布情况,且可靠性较高,可用于后续的水合物储层分析及综合研究。本文在无井约束的条件下,采用波阻抗反演技术开展适用于天然气水合物的识别研究,对未来的水合物勘探具有重要的现实意义。