CO_(2)capture costs of chemical looping combustion of biomass:A comparison of natural and synthetic oxygen carrier

Chemical looping combustion has the potential to be an efficient and low-cost technology capable of contributing to the reduction of the atmospheric concentration of CO_(2) in order to reach the 1.5/2°C goal and mitigate climate change.In this process,a metal oxide is used as oxygen carrier in a dual fluidized bed to generate clean CO_(2) via combustion of biomass.Most commonly,natural ores or synthetic materials are used as oxygen carrier whereas both must meet special requirements for the conversion of solid fuels.Synthetic oxygen carriers are characterized by higher reactivity at the expense of higher costs versus the lower-cost natural ores.To determine the viability of both possibilities,a techno-economic comparison of a synthetic material based on manganese,iron,and copper to the natural ore ilmenite was conducted.The synthetic oxygen carrier was characterized and tested in a pilot plant,where high combustion efficiencies up to 98.4%and carbon capture rates up to 98.5%were reached.The techno-economic assessment resulted in CO_(2) capture costs of 75 and 40€/tCO_(2) for the synthetic and natural ore route respectively,whereas a sensitivity analysis showed the high impact of production costs and attrition rates of the synthetic material.The synthetic oxygen carrier could break even with the natural ore in case of lower production costs and attrition rates,which could be reached by adapting the production process and recycling material.By comparison to state-of-the-art technologies,it is demonstrated that both routes are viable and the capture cost of CO_(2) could be reduced by implementing the chemical looping combustion technology.

Key technologies for wireless network digital twin towards smart railways

An emerging railway technology called smart railway promises to deliver higher transportation efficiency,enhanced comfort in services,and greater eco-friendliness.The smart railway is expected to integrate fifth-generation mobile communication(5G),Artificial Intelligence(AI),and other technologies,which poses new problems in the construction,operation and maintenance of railway wireless networks.Wireless Digital Twins(DTs),which have recently emerged as a new paradigm for the design of wireless networks,can address these problems and enable the whole lifecycle management of railway wireless networks.However,there are still many scientific issues and challenges for railway-oriented wireless DT.Relevant key technologies to solve these problems are introduced and described,including characterization of materials'physical-EM properties,autonomous reconstruction of Three-dimensional(3D)environment model,AI-empowered environmental cognition,Ray-Tracing(RT),model-based and AIbased RT acceleration,and generation of multi-spectra sensing data.Moreover,this paper presents our research results for each key technology and describes the wireless network planning and optimization system based on highperformance RT developed by our laboratory.This paper outlines the framework for realizing the wireless DT of smart railways,providing the direction for future research.

Visualization Working Group at TU Wien Visible Facimus Quod Ceteri Non Possunt

Building-up and running a university-based research group is a multi-faceted undertaking.The visualization working group at TU Wien(vis-group)has been internationally active over more than 25 years.The group has been acting in a competitive scientific setting where sometimes contradicting multiple objectives require trade-offs and optimizations.Research-wise the group has been performing basic and applied research in visualization and visual computing.Teaching-wise the group has been involved in undergraduate and graduate lecturing in(medical)visualization and computer graphics.To be scientifically competitive requires to constantly expose the group and its members to a strong international competition at the highest level.This necessitates to shield the members against the ensuing pressures and demands and provide(emotional)support and encouragement.Internally,the vis-group has developed a unique professional and social interaction culture:work and celebrate,hard and together.This has crystallized into a nested,recursive,and triangular organization model,which concretizes what it takes to make a research group successful.The key elements are the creative and competent vis-group members who collaboratively strive for(scientific)excellence in a socially enjoyable environment.

From Earth to Space:A First Deployment of 5G Core Network on Satellite

Recent developments in the aerospace industry have led to a dramatic reduction in the manufacturing and launch costs of low Earth orbit satellites.The new trend enables the paradigm shift of satelliteterrestrial integrated networks with global coverage.In particular,the integration of 5G communication systems and satellites has the potential to restructure nextgeneration mobile networks.By leveraging the network function virtualization and network slicing,the satellite 5G core networks will facilitate the coordination and management of network functions in satellite-terrestrial integrated networks.We are the first to deploy a 5G core network on a real-world satellite to investigate its feasibility.We conducted experiments to validate the satellite 5G core network functions.The validated procedures include registration and session setup procedures.The results show that the satellite 5G core network can function normally and generate correct signaling.

Structural, electronic and magnetic properties of Fe-doped strontium ruthenates

By employing a combined approach of density-functional theory(DFT) and dynamical mean-field theory(DMFT) calculations, we examine the structural, electronic, and magnetic characteristics of two distinct strontium ruthenates: Sr2RuO4,an unconventional superconductor, and the correlated metal SrRuO3, both at 50% Fe-doping level. In both Sr2Fe0.5Ru0.5O4and SrFe0.5Ru0.5O3, the original ruthenium(Ru) and the dopant iron(Fe) atoms adopt 3-dimensional and 2-dimensional G-type structures, respectively. The hybridization between Fe-3d and Ru-4d is comparatively weaker than in other double perovskite systems. The interplay between strong correlations and reduced itinerancy results in significant spin splitting at Fe and Ru sites. Consequently, a charge transfer process, along with the super-exchange effect, leads to antiferromagnetically coupled Fe3+and Ru5+ions and establishes a semiconducting ferrimagnetic order. Subsequent DMFT calculations demonstrate the persistence of the ferrimagnetic order even at room temperature(300 K). These findings align with prior reports on Sr Fe0.5Ru0.5O3, thus reinforcing the notion that 3d–4d transition metal oxides hold considerable promise as candidates for high-performance spintronic devices, such as spin-valve sensors and spintronic giant magnetoresistance devices.

COVID-19:Masks do not influence neurocognitive performance during a shift at the emergency department

The COVID-19 pandemic has led to the widespread mandatory use of personal protective equipment(PPE),including filtering face pieces(FFP).Emergency medical care providers now commonly use this equipment.

Electronic structure of cuprate-nickelate infinite-layer heterostructure

The discovery of superconductivity in Sr/Ca-doped infinite-layer nickelates Nd(La)NiO_(2)thin films inspired extensive experimental and theoretical research.However,research on the possibilities of enhanced critical temperature by interface heterostructure is still lacking.Due to the similarities of the crystal structure and band structure of infinite-layer nickelate La NiO_(2)and cuprate CaCuO_(2),we investigate the crystal,electronic and magnetic properties of La NiO_(2):CaCuO_(2)heterostructure using density functional theory and dynamical mean-field theory.Our theoretical results demonstrate that,even a very weak inter-layer z-direction bond is formed,an intrinsic charge transfer between Cu-3d_(x^(2)-y^(2))and Ni-3d_((x^(2)-y^(2)))orbitals is obtained.The weak interlayer hopping between Cu and Ni leaves a parallel band contributed by Ni/Cu-3d_((x^(2)-y^(2)))orbitals near the Fermi energy.Such an infinite-layer heterostructure with negligible interlayer interaction and robust charge transfer opens a new way for interface engineering and nickelate superconductors.

Research on Traffic Sign Detection Based on Improved YOLOv8

Aiming at solving the problem of missed detection and low accuracy in detecting traffic signs in the wild, an improved method of YOLOv8 is proposed. Firstly, combined with the characteristics of small target objects in the actual scene, this paper further adds blur and noise operation. Then, the asymptotic feature pyramid network (AFPN) is introduced to highlight the influence of key layer features after feature fusion, and simultaneously solve the direct interaction of non-adjacent layers. Experimental results on the TT100K dataset show that compared with the YOLOv8, the detection accuracy and recall are higher. .

Design and Development of Low-cost Wearable Electroencephalograms (EEG) Headset

Electroencephalogram(EEG)is a method of capturing the electrophy-siological signal of the brain.An EEG headset is a wearable device that records electrophysiological data from the brain.This paper presents the design and fab-rication of a customized low-cost Electroencephalogram(EEG)headset based on the open-source OpenBCI Ultracortex Mark IV system.The electrode placement locations are modified under a 10–20 standard system.The fabricated headset is then compared to commercially available headsets based on the following para-meters:affordability,accessibility,noise,signal quality,and cost.First,the data is recorded from 20 subjects who used the EEG Headset,and signals were recorded.Secondly,the participants marked the accuracy,set up time,participant comfort,and participant perceived ease of set-up on a scale of 1 to 7(7 being excellent).Thirdly,the self-designed EEG headband is used by 5 participants for slide changing.The raw EEG signal is decomposed into a series of band sig-nals using discrete wavelet transform(DWT).Lastly,thesefindings have been compared to previously reported studies.We concluded that when used for slide-changing control,our self-designed EEG headband had an accuracy of 82.0 percent.We also concluded from the results that our headset performed well on the cost-effectiveness scale,had a reduced setup time of 2±0.5 min(the short-est among all being compared),and demonstrated greater ease of use.

纯γ-Mn的电子、基态属性和磁有序结构

采用第一原理方法,基于ultrasoft赝势、密度函数理论,从原子层面对纯γ-Mn的顺磁、铁磁和反铁磁性状态下的电子、基态属性、相稳定和磁有序结构进行了研究.通过自旋极化分析讨论了纯γ-Mn这3种磁性状态的结构稳定性,发现在基态时,反铁磁性状态的γ-Mn结构最稳定,且Mn原子处于高自旋状态,其理论磁通量为2.41μB/atom,这与实验结果吻合通过局部状态密度（DOS）,分析了它们的键和磁有序特性,发现主要是位于Fermi态附近的3d轨道电子对磁性起决定性的作用,其向上自旋和向下自旋的主峰分别处于Fermi能下面的键区和Fermi能上面的反键区.通过比较这3种磁性状态可知,反铁磁的γ-Mn存在显著的磁体积效果.

颈髓段下行传导束诱发电位动物模型研究

目的 :建立 SD鼠脊髓下行传导束诱发电位 ( MEP)模型。 方法 :刺激颈髓段下行传导束 ,于双侧坐骨神经记录电位变化。采用 8个不同刺激强度区间 ,并结合脊髓部分损伤状态 ,评价其潜伏期和波幅的变化。结果 :诱发电位主要由 3个正负波峰组成。 N1的潜伏期 :右侧 ( 2 .89± 0 .2 2 ) ms,左侧 ( 2 .89± 0 .2 4) ms。传导速度 47.9m/s。 N1的波幅 :右侧 ( 3 .61± 2 .10 )μV,左侧 ( 3 .83± 2 .3 2 )μV。不同刺激强度组间潜伏期相差不显著 ,但组间波幅有显著性差异 (右侧 F =2 .2 2 ,df =72 0 1,P=0 .0 3 ;左侧 F =2 .11,df=72 0 6,P=0 .0 4)。 T9平面脊髓部分损伤后 ,潜伏期延长 ,右侧 14 % ,左侧 12 % ;波幅下降 ,右侧5 9 % ,左侧 3 1%。结论 :建立的颈髓段下行传导束诱发电位动物模型有效、可靠 ,重复性好。

半导体与超晶格的数学模型及其分析Ⅱ:分析<英>

本文先介绍等熵可压缩Euler方程的相关补偿列紧框架.然后,我们综述基于补偿列紧方法的关于半导体流体动力模型的诸如整体弱解,松弛极限和拟中性.松弛极限的一些新近数学结果.

半导体与超晶格的数学模型及其分析Ⅰ:模型(英文)

本文论及半导体与超晶格的数学模型方法的一些新近发展动态.介绍了半导体与超 晶格的一些背景材料并给出了半导体宏观模型间的层次框架.超晶格中载流子传输的SHE扩散 模型也被观察.

Ni_3Ga中间相结构缺陷的热力学和统计热力学分析

使用以稳定的ZrO2为电解质的高温固体电解质电池电动势方法测量了Ni3Ga非整比金属间化合物1073至1273K均相范围内Ga的活度，计算了偏摩尔焓和偏摩尔摘等热力学性质．考虑4种点缺陷，即分别在2个亚晶格上的反结构原子和空位共存于该Ll2型化合物中，各缺陷生成自由能为可调参数：Ef（Aβ）＝0．60eV，Ef（Bα）＝0．60eV，EfV（α）＝1．5eV，EfV（β）＝2．0eV，用统计热力学方法推导了Ni3Ga非整比化合物均相范围内缺陷浓度及其与温度和成分的关系，得到1123K时整比处的无序参数a’＝0．0009．

奥地利古典音乐与音乐厅的发展沿革

分析、总结奥地利古典音乐的历史渊源、发展过程以及奥地利音乐厅的形成、演变,介绍奥地利首都维也纳经典音乐厅,并从建筑声学角度分析其音质特点,以使国内建筑师对欧洲音乐厅建筑有较全面的了解。

Ni-Ga二元系的热力学计算

采用 ＣＡＬＰＨＡＤ技术评估了Ｎｉ－Ｇａ二元系的相图和热力学性质．用双亚晶格模型描 述２个有序相（Ｌ１２－Ｎｉ３Ｇａ和Ｂ２－ＮｉＧａ）的热力学行为，并在优化过程中考虑了ｆｃｃ－（Ｎｉ）和Ｌ１２Ｎｉ３Ｇａ 相的有序－无序转变．溶液相（液相、ｆｃｃ－（Ｎｉ）固溶体）的热力学模型采用Ｒｅｄｌｉｃｈ－Ｋｉｓｔｅｒ方程，其 余５个中间化合物被视为整比化合物．

几种含羟基化合物对红细胞膜流动性的影响

利用氮氧自由基自旋标记物CAT-16和5-DSA较为详尽地探讨了两类含羟基化合物-羟胺衍生物与苯酚取代物对红细胞膜流动性变化的影响.实验结果表明:当非双亲性的小分子苯酚取代物插入红细胞膜内,膜的整体有序性降低和流动性增加;羟胺衍生物可作为促氧化剂诱导产生过氧化自由基,促使膜内磷脂间发生化学偶联,从而降低生物膜的内部流动性.在红细胞膜的表面,标记物分子运动基本不受偶联影响,综合效应来自小分子插入导致的膜流动性增加.

下颌骨透亮灶

借助X线平片和鉴别诊断标准,一般来说对下颌骨透亮灶不难作出诊断,可以按其来源进行分类.本文不涉及CT和MRT诊断,这两种方法可用于进一步确诊.

脂肪栓塞的病理生理

近100年来,脂肪栓塞是创伤外科重要并发症,Gurd 将其临床表现统称为脂肪栓塞综合征(FES)。1970年以来,已报道了大量关节置换术发生 FES死亡的病例,并发现长管骨骨折、骨折髓内针内固定的手术创伤均可导致 FES。骨科和创伤外科 FES 病理生理变化可分为三个阶段:骨髓溢出、肺部骨髓栓塞、呼吸功能障碍。

骨肿瘤诊断中的“陷阱”和典型误诊

骨肿瘤和肿瘤样骨病变的判断对于未曾经过专门培训的病理学工作者来说常是困难的.