Novel Perovskite Oxide Hybrid Nanofibers Embedded with Nanocatalysts for Highly Efficient and Durable Electrodes in Direct CO_(2) Electrolysis

The unique characteristics of nanofibers in rational electrode design enable effec-tive utilization and maximizing material properties for achieving highly efficient and sustainable CO_(2) reduction reactions( CO_(2)RRs)in solid oxide elec-trolysis cells(SOECs).However,practical appli-cation of nanofiber-based electrodes faces chal-lenges in establishing sufficient interfacial contact and adhesion with the dense electrolyte.To tackle this challenge,a novel hybrid nanofiber electrode,La_(0.6)Sr_(0.4)Co_(0.15)Fe_(0.8)Pd_(0.05)O_(3-δ)(H-LSCFP),is developed by strategically incorporating low aspect ratio crushed LSCFP nanofibers into the excess porous interspace of a high aspect ratio LSCFP nanofiber framework synthesized via electrospinning technique.After consecutive treatment in 100% H_(2) and CO_(2) at 700°C,LSCFP nanofibers form a perovskite phase with in situ exsolved Co metal nanocatalysts and a high concentration of oxygen species on the surface,enhancing CO_(2) adsorption.The SOEC with the H-LSCFP electrode yielded an outstanding current density of 2.2 A cm^(-2) in CO_(2) at 800°C and 1.5 V,setting a new benchmark among reported nanofiber-based electrodes.Digital twinning of the H-LSCFP reveals improved contact adhesion and increased reaction sites for CO_(2)RR.The present work demonstrates a highly catalytically active and robust nanofiber-based fuel electrode with a hybrid structure,paving the way for further advancements and nanofiber applications in CO_(2)-SOECs.

甘油三酯催化转化为柴油、喷气燃料和润滑油基础油

将生物质转化为可持续燃料和化学品对于解决环境问题、减少碳排放、增强能源安全以及促进经济和社会发展至关重要.在众多生物质原料中,来自不同来源的甘油三酯,如植物油、动物脂肪和微藻油,因其低氧含量和脂肪酸单元中的高度石蜡骨架,与石油衍生烃的结构相似,而特别适合生产可持续的烃燃料和化学品.这意味着通过相对简单的催化转化过程,就能有效地将甘油三酯转化为烃类产物.本文概述了甘油三酯通过加氢过程转化为无氧燃料(如柴油和喷气燃料)以及润滑油基础油等高附加值产品的过程.此外,还根据反应机理讨论了所需催化剂的重要结构性质,以及甘油三酯的不同脂肪酸组成对催化转化过程的影响.

Postmortem ^(7)Li NMR analysis for assessing the reversibility of lithium metal electrodes in lithium metal batteries

Despite the proficiency of lithium(Li)-7 NMR spectroscopy in delineating the physical and chemical states of Li metal electrodes,challenges in specimen preparation and interpretation impede its progress.In this study,we conducted a comprehensive postmortem analysis utilizing ^(7)Li NMR,employing a stan-dard magic angle spinning probe to examine protective-layer coated Li metal electrodes and LiAg alloy electrodes against bare Li metal electrodes within Li metal batteries(LMBs).Our investigation explores the effects of sample burrs,alignment with the magnetic field,the existence of liquid electrolytes,and precycling on the ^(7)Li NMR signals.Through contrasting NMR spectra before and after cycling,we identi-fied alterations in Li^(0) and Li^(+) signals attributable to the degradation of the Li metal electrode.Our NMR analyses decisively demonstrate the efficacy of the protective layer in mitigating dendrite and solid elec-trolyte interphase formation.Moreover,we noted that Li*ions near the Li metal surface exhibit magnetic susceptibility anisotropy,revealing a novel approach to studying diamagnetic species on Li metal elec-trodes in LMBs.This study provides valuable insights and practical guidelines for characterizing distinct lithium states within LMBs.

Decoding RoPax Ship Capsizes and Development of an ISO Ship Safety Standard

Marine accidents often result in significant losses of human life, environmental damage, and property destruction. Additionally, ships and offshore plants are large-scale and complex systems, making safety assessments challenging. However, the advent of onboard electronic systems has made it possible to monitor and respond more effectively. These new technologies can enhance safety levels while reducing the workload on crews. In this paper, authors analyze recent accidents involving ships with high structures above the water, such as car carriers or RoPax vessels, and propose preventive safety indicators to help prevent similar accidents from recurring.

Panel Discussion on“Development Trends of Computer Science in the New Era”

At the panel session of the 3rd Global Forum on the Development of Computer Science,attendees had an opportunity to deliberate recent issues affecting computer science departments as a result of the recent growth in the field.6 heads of university computer science departments participated in the discussions,including the moderator,Professor Andrew Yao.The first issue was how universities are managing the growing number of applicants in addition to swelling class sizes.Several approaches were suggested,including increasing faculty hiring,implementing scalable teaching tools,and working closer with other departments through degree programs that integrate computer science with other fields.The second issue was about the position and role of computer science within broader science.Participants generally agreed that all fields are increasingly relying on computer science techniques,and that effectively disseminating these techniques to others is a key to unlocking broader scientific progress.

Light-Material Interactions Using Laser and Flash Sources for Energy Conversion and Storage Applications

This review provides a comprehensive overview of the progress in light-material interactions(LMIs),focusing on lasers and flash lights for energy conversion and storage applications.We discuss intricate LMI parameters such as light sources,interaction time,and fluence to elucidate their importance in material processing.In addition,this study covers various light-induced photothermal and photochemical processes ranging from melting,crystallization,and ablation to doping and synthesis,which are essential for developing energy materials and devices.Finally,we present extensive energy conversion and storage applications demonstrated by LMI technologies,including energy harvesters,sensors,capacitors,and batteries.Despite the several challenges associated with LMIs,such as complex mechanisms,and high-degrees of freedom,we believe that substantial contributions and potential for the commercialization of future energy systems can be achieved by advancing optical technologies through comprehensive academic research and multidisciplinary collaborations.

Unassisted overall water splitting with a solar-to-hydrogen efficiency of over 10% by coupled lead halide perovskite photoelectrodes

Hydrogen is a promising future sustainable fuel candidate with boundless opportunities.Research into photoelectrochemical(PEC)water splitting based on a lead halide perovskite(LHP)has progressed significantly with the aim of more efficient solar hydrogen production.Herein,we unite a well-known photo-absorbing LHP with cost-effective water-splitting catalysts,and we introduce two types of monolithic LHP-based PEC devices that act as a photocathode and a photoanode for the hydrogen evolution reaction and oxygen evolution reaction,leading to efficient unbiased overall water splitting.Through the integration of these two monolithic LHP-based photoelectrodes,an unbiased solar-to-hydrogen conversion efficiency of 10.64%and a photocurrent density of 8.65 mA cm^(−2) are achieved.

Flash‑Induced High‑Throughput Porous Graphene via Synergistic Photo‑Effects for Electromagnetic Interference Shielding

Porous 2D materials with high conductivity and large surface area have been proposed for potential electromagnetic interference(EMI)shielding materials in future mobility and wearable applications to prevent signal noise,transmission inaccuracy,system malfunction,and health hazards.Here,we report on the synthesis of lightweight and flexible flash-induced porous graphene(FPG)with excellent EMI shielding performance.The broad spectrum of pulsed flashlight induces photo-chemical and photo-thermal reactions in polyimide films,forming 5×10 cm^(2)-size porous graphene with a hollow pillar structure in a few milliseconds.The resulting material demonstrated low density(0.0354 g cm^(−3))and outstanding absolute EMI shielding effectiveness of 1.12×10^(5) dB cm^(2) g^(−1).The FPG was characterized via thorough material analyses,and its mechanical durability and flexibility were confirmed by a bending cycle test.Finally,the FPG was utilized in drone and wearable applications,showing effective EMI shielding performance for internal/external EMI in a drone radar system and reducing the specific absorption rate in the human body.

Electrochemical Water Splitting:Bridging the Gaps Between Fundamental Research and Industrial Applications

Electrochemical water splitting represents one of the most promising technologies to produce green hydrogen,which can help to realize the goal of achieving carbon neutrality.While substantial efforts on a laboratory scale have been made for understanding fundamental catalysis and developing high-performance electrocatalysts for the two half-reactions involved in water electrocatalysis,much less attention has been paid to doing relevant research on a larger scale.For example,few such researches have been done on an industrial scale.Herein,we review the very recent endeavors to bridge the gaps between fundamental research and industrial applications for water electrolysis.We begin by introducing the fundamentals of electrochemical water splitting and then present comparisons of testing protocol,figure of merit,catalyst of interest,and manufacturing cost for laboratory and industry-based water-electrolysis research.Special attention is paid to tracking the surface reconstruction process and identifying real catalytic species under different testing conditions,which highlight the significant distinctions of corresponding electrochemical reconstruction mechanisms.Advances in catalyst designs for industry-relevant water electrolysis are also summarized,which reveal the progress of moving the practical applications forward and accelerating synergies between material science and engineering.Perspectives and challenges of electrocatalyst design strategies are proposed finally to further bridge the gaps between lab-scale research and large-scale electrocatalysis applications.

Estimation of plasma parameters of X-pinch with time-resolved x-ray spectroscopy

We estimate the parameters of a Cu plasma generated by an X-pinch by comparing experimentally measured x-rays with synthetic data.A filtered absolute extreme ultraviolet diode array is used to measure time-resolved x-ray spectra with a spectral resolution of∼1 keV in the energy range of 1–10 keV.The synthetic spectra of Cu plasmas with different electron temperatures,electron densities,and fast electron fractions are calculated using the FLYCHK code.For quantitative comparison with the measured spectrum,two x-ray power ratios with three different spectral ranges are calculated.We observe three x-ray bursts in X-pinch experiments with two Cu wires conducted on the SNU X-pinch at a current rise rate of∼0.2 kA/ns.Analysis of the spectra reveals that the first burst comprises x-rays emitted by hot spots and electron beams,with characteristics similar to those observed in other X-pinches.The second and third bursts are both generated by longlived electron beams formed after the neck structure has been completely depleted.In the second burst,the formation of the electron beam is accompanied by an increase in the electron density of the background plasma.Therefore,the long-lived electron beams generate the additional strong x-ray bursts while maintaining a plasma channel in the central region of the X-pinch.Moreover,they emit many hard x-rays(HXRs),enabling the SNU X-pinch to be used as an HXR source.This study confirms that the generation of long-lived electron beams is crucial to the dynamics of X-pinches and the generation of strong HXRs.

(EDTA)^(4-) supplements as superior modifier of the in-vitro-degradation properties of the magnesium alloy coated through discharge-assisted process

The(EDTA)^(4-)organic substituents were supplemented with alkaline silicates electrolyte,however in varying concentration to explore the microstructure,chemical composition and subsequent effects on the biodegradation of the PEO coated Mg AZ91 alloy.From surface analysis-,carried out through SEM,samples with zero-(EDTA)^(4-)were found-,lacking pancake structural features;however,supplementing electrolyte with(EDTA)^(4-),bulky and layered pancakes were obtained with minimum cracks and minimum porosity for EDT-1.From the phase and inner layer analysis,it was found that EDTA can significantly alter the surface layers composition and could act as a passivation agent-;however,individual polycrystalline phases were not found to form.The hardness value obtained for EDT-1 was~909.69 HV,the highest value found here which occurs with the shallowest indents found in this study.In-vitro degradation analysis was carried out using potentiodynamic polarization at room temperature,cyclic polarization at RT and high fever conditions(HFT~40°C).The corrosion potential for coated AZ91 was obtained as a positive value of~0.1 V,for the first time in the PEO research;however,the results were not supported by the cyclic polarization tests at room temperature and at HFT.The post corrosion microstructural analysis confirmed the effective role of EDTA up to 1.0 g·L^(-1)and revealed the formation of thin films during the forward polarization at HFT.

Elucidating the evolution of long-period stacking ordered phase and its effect on deformation behavior in the as-cast Mg-6Gd-1Zn-0.6Zr alloy

Herein,the evolution of long-period stacking ordered(LPSO)phases in the as-cast Mg-6Gd-1Zn-0.6Zr(wt.%)alloy are investigated via transmission electron microscopy(TEM)and atom probe tomography(APT).The TEM results reveal that two types of LPSO phase(a bulky interdendritic phase and a plate-like matrix LPSO phase)are formed in the as-cast sample.Most of the LPSO phases are confirmed to be of the 14H type,with a smaller proportion being of the 18R LPSO.Further,the APT results reveal that the composition of the interdendritic LPSO phase is closer to that of the ideal 14H phase compared to the matrix LPSO phase,and both the interdendritic and matrix LPSO phases exhibit a Gd/Zn ratio of 2.5,thereby indicating a deficient Zn content compared to the ideal 14H phase(i.e.,1.3).In addition,the influence of the LPSO phases on the deformation behavior is investigated at different compressive plastic strains using electron backscatter diffraction(EBSD)analysis to reveal twinning and slip behavior during deformation.The results indicate that the LPSO phase induces additional work hardening in the late stage of deformation via the suppression of{1011}compressive twinning and the activation of non-basal slip systems.

Elucidating the promotion mechanism of the ternary cooperative heterostructure toward industrial-level urea oxidation catalysis

From the perspective of electronic structure modulation,it is highly desirable to rationally design the active urea oxidation reaction(UOR)catalysts through interface engineering.The binary cooperative heterostructure systems have been shown significant enhancement for catalyzing UOR,but their performance still remains unsatisfactory for industrialization because of the unfavorable intermediate adsorption/desorption and deficient electron transfer channels.In response,taking the ternary cooperative Ni_5P_(4)/NiSe_(2)/Ni_(3)Se_(4) heterostructure as the proof-of-concept paradigm,a catalytic model is rationally put forward to elucidate the UOR promotion mechanism at the molecular level.The rod-like Ni_5P_(4)/NiSe_(2)/Ni_(3)Se_(4) nanoarrays with three-phase heterojunction are experimentally fabricated on Ni foam(named as Ni_5P_(4)/NiSe_(2)/Ni_(3)Se_(4)/NF)via simple two-step processes.The density functional theory calculations disclose that construction of Ni_5P_(4)/NiSe_(2)/Ni_(3)Se_(4) heterostructure model not only induce charge redistribution at the interfacial region for creating innumerable electron transfer channels,but also endow it with a moderate d-band center that could help to build a balance between adsorption and desorption of diverse UOR intermediates.Benefiting from the unique rod-like nanoarrays with large specific surface area and the optimized electronic structure,the well-designed Ni_5P_(4)/NiSe_(2)/Ni_(3)Se_(4)/NF could act as a robust catalyst for driving UOR at industrial-level current densities under tough environments,offering great potential for commercial applications.

An amorphous manganese iron oxide hollow nanocube cathode for aqueous zinc ion batteries

Aqueous zinc ion batteries(ZIBs) are attracting considerable attentions for practical energy storage because of their low cost and high safety.Nevertheless,the traditional manganese oxide cathode materials suffer from the low intrinsic electronic conductivity,sluggish ions diffusion kinetics,and structural collapse,hindering their large-scale application.Herein,we successfully developed a latent amorphous Mn_(1.8)Fe_(1.2)O_(4) hollow nanocube(a-H-MnFeO) cathode material derived from Prussian blue analogue precursor.The amorphous nature endows the cathode with lower diffusion barrier and narrower band gap compared with crystalline counterpart,resulting in the superior Zn^(2+) ions and electrons transport kinetics.Hollow structure can furnish abundant surface sites and suppress the structural collapse during the repeated charge/discharge processes.By virtue of the multiple advantageous features,the a-H-MnFeO cathode exhibits exceptional electrochemical performance,in terms of high capacity,excellent rate capability,and prolonged cycle life.This strategy will pave the way for the structural design of emerging cathode materials.

Spatial Control of Lithium Deposition by Controlling the Lithiophilicity with Copper(Ⅰ)Oxide Boundaries

Spatial control of lithium deposition is the most important issue in lithium-metal batteries because of the considerable control of lithium dendrite suppression via the uniform distribution of Li^(+)flux.Although seed materials are crucial for the behavior of lithium deposition,in-depth studies on their physical and chemical control have not been conducted.Here,we describe a new design of seed structure comprising a wrinkled Cu/graphene substrate surrounded by copper(Ⅰ)oxide(Cu_(2)O)on a graphene grain boundary over a large area,which is fabricated by the oxidation of the Cu surface via graphene boundary defects by using chemical vapor deposition(CVD).Scanning and transmission electron microscopy results reveal that Cu_(2)O on the graphene boundary can render a preferential reaction with lithium during the first deposition and assist in the uniform deposition of lithium by preventing the agglomeration of lithium clusters during the second deposition.This two-step process is attributed to the degree of selectivity due to the difference in lithium affinity,which allows long-term electrochemical stability and a high rate capability via boundary effects.This study highlights the significance of the boundary effect,which can open new avenues for the formation of a large family of seed structures in lithium-metal batteries.

发动机混合支承系统的LQG控制

研究了一种用于发动机混合支承的智能控制的在频域内设计一线性多变量控制的方法。该设计使用了优化控制理论。对典型的四缸四冲程发动机的干扰力和力矩进行了分析并将其用于优化控制系统。对未使用和使用控制器的结果进行比较后表明 。

基于图交互与场景感知融合的轨迹预测方法

在自动驾驶中,精确的环境感知和对周围交通参与者的轨迹预测对道路安全至关重要。基于此,提出了基于鸟瞰图(Bird Eye View, BEV)的实时端到端轨迹预测框架来同时学习交互和场景信息。该框架主要由图交互网络和金字塔感知网络两个模块组成,前者通过时空图卷积网络对交通参与者之间的交互模式进行编码,后者采用时空金字塔网络对周围信息进行场景建模以获取场景特征。然后,对交互特征和场景特征进行单一尺度融合,从而进行分类和轨迹预测任务。在大规模开源数据集NuScenes上的实验和分析表明,与当前先进算法(MotionNet)相比,所提框架平均类别准确度提高了3.1%,轨迹预测平均误差在行驶速度>5m/s时降低了1.43%。此实验结果表明,所提模型具有更好的泛化性和鲁棒性,更符合实际自动驾驶环境中的轨迹预测需求。

汞胁迫对4个草坪草品种幼苗生理特性及养分积累的影响

[目的]为汞污染地区土壤生物修复提供合适的草坪草品种。[方法]通过土培盆栽试验模拟汞胁迫环境,选取4个不同草坪草品种(黑麦草马达,一年生黑麦草盛宴,紫羊茅派尼和传奇),测定不同浓度Hg^2+胁迫下草坪草幼苗叶绿素含量、叶片原初光能转化效率(Fv/Fm)、可溶性糖(SS)含量、超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量、叶片相对电导率及植株的N、P、K积累特性。[结果]随着Hg2+浓度升高,4个草坪草叶片叶绿素含量、Fv/Fm以及N、P、K积累持续下降,SS含量和SOD活性先升后降,MDA含量和叶片相对电导率持续上升。75~100 mg/kg Hg^2+胁迫下,4个草坪草叶绿素含量、Fv/Fm值、SS含量、SOD活性和N、P、K积累量较对照(空白)均显著下降(P<0.05),MDA含量和相对电导率则显著上升(P<0.05),高浓度Hg2+胁迫明显影响4个草坪草幼苗叶片细胞膜透性及N、P、K积累量,从而使植株生长受到严重抑制甚至死亡。[结论]对比4个草坪草品种在不同浓度Hg^2+胁迫下各项指标的变化情况,Hg2+胁迫下一年生黑麦草盛宴比黑麦草马达、紫羊茅派尼和传奇受到的伤害程度低,显示出较强的耐汞胁迫能力,可作为汞污染土壤生物修复中优选的草坪草品种。

Injection Strategy in Natural Gas–Diesel Dual-Fuel Premixed Charge Compression Ignition Combustion under Low Load Conditions

Dual-fuel premixed charge compression ignition (DF-PCCI) combustion has been proven to be a viable alternative to conventional diesel combustion in heavy-duty compression ignition engines due to its low nitrogen oxides (NOx) and particulate matter (PM) emissions. When natural gas (NG) is applied to a DF-PCCI engine, its low reactivity reduces the maximum pressure rise rate under high loads. However, the NG–diesel DF-PCCI engine suffers from low combustion efficiency under low loads. In this study, an injection strategy of fuel supply (NG and diesel) in a DF-PCCI engine was investigated in order to reduce both the fuel consumption and hydrocarbon (HC) and carbon monoxide (CO) emissions under low load conditions. A variation in the NG substitution and diesel start of energizing (SOE) was found to effectively control the formation of the fuel–air mixture. A double injection strategy of diesel was implemented to adjust the local reactivity of the mixture. Retardation of the diesel pilot SOE and a low fraction of the diesel pilot injection quantity were favorable for reducing the combustion loss. The introduction of exhaust gas recirculation (EGR) improved the fuel economy and reduced the NOx and PM emissions below Euro VI regulations by retarding the combustion phasing. The combination of an NG substitution of 40%, the double injection strategy of diesel, and a moderate EGR rate effectively improved the combustion efficiency and indicated efficiency, and reduced the HC and CO emissions under low load conditions.

Recent advances in lithographic fabrication of micro-/nanostructured polydimethylsiloxanes and their soft electronic applications

The intensive development of micro-/nanotechnologies offers a new route to construct sophisticated architectures of emerging soft electronics.Among the many classes of stretchable materials,micro-/nanostructured poly(dimethylsiloxane)(PDMS)has emerged as a vital building block based on its merits of flexibility,stretchability,simple processing,and,more importantly,high degrees of freedom of incorporation with other functional materials,including metals and semiconductors.The artificially designed geometries play important roles in achieving the desired mechanical and electrical performances of devices and thus show great potential for applications in the fields of stretchable displays,sensors and actuators as well as in health-monitoring device platforms.Meanwhile,novel lithographic methods to produce stretchable platforms with superb reliability have recently attracted research interest.The aim of this review is to comprehensively summarize the progress regarding micro-/nanostructured PDMS and their promising soft electronic applications.This review is concluded with a brief outlook and further research directions.