Electrochemistry and DFT study of galvanic interaction on the surface of monoclinic pyrrhotite(001)and galena(100)

The electrochemical interaction between galena and monoclinic pyrrhotite was investigated to examine its impact on the physical and chemical properties of the mineral micro-surface.This investigation employed techniques such as electrochemistry,metal ion stripping,X-ray photoelectron spectroscopy,and quantum chemistry.The electrochemical test results demonstrate that the galena surface in the electro-couple system exhibits a lower electrostatic potential and higher electrochemical activity compared to the monoclinic pyrrhotite surface,rendering it more susceptible to oxidation dissolution.Monoclinic pyrrhotite significantly amplifies the corrosion rate of the galena surface.Mulliken charge population calculations indicate that electrons are consistently transferred from galena to monoclinic pyrrhotite,with the number of electron transfers on the mineral surface increasing as the interaction distance decreases.The analysis of state density revealed a shift in the surface state density of galena towards lower energy levels,resulting in decreased reactivity and increased difficulty for the reagent to adsorb onto the mineral surface.Conversely,monoclinic pyrrhotite exhibited an opposite trend.The X-ray photoelectron spectroscopy(XPS)test results indicate that galvanic interaction leads to the formation of hydrophilic substances,PbS_(x)O_(y) and Pb(OH)_(2),on the surface of galena.Additionally,the surface of monoclinic pyrrhotite not only adsorbs Pb^(2+)but also undergoes S^(0) formation,thereby augmenting its hydrophobic nature.

汽车及零部件电磁兼容测试方法基于ECE R10的变化解析

汽车电子电磁兼容性不仅是评价汽车及零部件的重要性能指标之一,也是汽车及零部件出口国外市场必要的测试之一,车企出口欧盟需要满足《关于车辆电磁兼容性能认证的统一规定》(ECE R10)要求并遵照法规要求进行电磁兼容测试。本文对比了新旧版本ECE R10对于测试方法与要求的变化,为开展汽车电子产品的电磁兼容检测和认证提供参考。

基于频率匹配的EC模式定量降水偏差订正

为了提升模式预报效果,文章利用四川盆地南部20182020年59月的EC模式降水预报资料和实况降水资料,采用频率匹配的方法对EC模式的24 h累计降水进行订正、分析和检验。结果表明当降水阈值小于25.0 mm时,EC模式定量降水预报存在明显湿偏差,反之存在弱干偏差。研究结果为提升相关区域的降水预报能力提供支持。

基于频率匹配的EC模式定量降水偏差订正

为了提升模式预报效果,文章利用四川盆地南部2018-2020年5-9月的EC模式降水预报资料和实况降水资料,采用频率匹配的方法对EC模式的24 h累计降水进行订正分析和检验,给出了预报偏差订正系数。研究结果能够提升相关区域的降水预报能力。

Unveiling the redox electrochemistry of 1D,urchin-like vanadium sulfide electrodes for high-performance hybrid supercapacitors

Exploring novel versatile electrode materials with outstanding electrochemical performance is the key to the development of advanced energy conversion and storage devices.In this work,we aim to construct new-fangled one-dimensional(1D)quasi-layered patronite vanadium tetrasulfide(VS_(4))nanostructures by using different sulfur sources,namely thiourea,thioacetamide,and L-cysteine through an ethyleneaminetetraacetic-acid(EDTA)-mediated solvothermal process.The as-prepared VS4exhibits several unique morphologies such as urchin,fluffy nanoflower,and polyhedron with appropriate surface areas.Among the prepared nanostructures,the VS_(4)-1@NF nanostructure exhibited excellent electrochemical properties in 6 M KOH solution,and we explored its redox electrochemistry in detail.The asprepared VS_(4)-1@NF electrode exhibited battery-type redox characteristics with the highest capacity of280 C g^(-1)in a three-electrode assembly.Moreover,it offered a capacity of 123 F g^(-1)in a hybrid twoelectrode set-up at 1 A g^(-1)with the highest specific energy and specific power of 38.5 W h kg^(-1)and750 W kg^(-1),respectively.Furthermore,to ensure the practical applicability and real-world performance of the prepared hybrid AC@NF//VS_(4)-1@NF cell,we performed a cycling stability test with more than 5,000galvanostatic charge–discharge cycles at 2 A g^(-1),and the cell retained around 84.7%of its capacitance even after 5,000 cycles with a CE of 96.1%.

EC130温拌剂对SBS改性沥青高温性能及抗疲劳性能的影响

作为制备沸石发泡沥青的发泡剂,EC130温拌剂释放的发泡水和残留的沸石矿物对沥青的性能有着不同的影响.为研究EC130温拌剂对SBS改性沥青高温性能和抗疲劳性能的影响,采用石灰岩矿粉、EC130沸石矿物和EC130温拌剂等3种添加物,设计了以添加物掺量为变量的单因素试验.以石灰岩矿粉为参照对象,通过温度扫描试验、多重应力蠕变恢复试验和线性振幅扫描试验,分析了EC130沸石矿物和EC130温拌剂释放的发泡水对SBS改性沥青高温性能和抗疲劳性能的影响.结果表明:同石灰岩矿粉一样,沸石发泡沥青中的EC130沸石矿物使沥青弹性增大、黏性减小,有利于抗车辙性能的提升,但不利于抗疲劳性能;沸石发泡沥青中的发泡水使其黏性增大、弹性减小,有利于抗疲劳性能的提升,但不利于抗车辙性能.

Conversion electrochemistry of copper selenides for robust and energetic aqueous batteries

The development of highly safe and low-cost aqueous batteries is of great significance in the background of carbon neutrality.However,the practical deployment of aqueous batteries has been plagued due to their relatively low capacity and poor cycling stability.Herein,we propose unique conversion electrochemistry of copper selenides for robust and energetic aqueous charge storage.In situ X-ray diffraction and operando Raman techniques reveal a reversible transformation from CuSe to Cu_(2)Se through the intermediates of Cu_(3)Se_(2) and Cu_(1.8)Se.Such a conversion process activates the redox carrier of Cu^(2+)ion and delivers a remarkable rate capability of 285 mAh g^(-1) at 20 A g^(-1) and electrochemical durability up to 30,000 cycles.Furthermore,Cu^(2+)and H+coinsertion chemistry is proposed to facilitate the conversion process.As a proof-of-concept,a hybrid aqueous pouch cell coupling CuSe//Zn is capable of affording maximum energy and power densities of 190 Wh kg^(-1) and 1366W kg^(-1),respectively.

Active MoS_(2)-based electrode for green ammonia synthesis

Nitrogen electro-reduction under mild conditions is one promising alternative approach of the energyconsuming Haber-Bosch process for the artificial ammonia synthesis.One critical aspect to unlocking this technology is to discover the catalysts with high selectivity and efficiency.In this work,the N_(2)-to-NH_(3)conversion on the functional MoS_(2)is fully investigated by density functional theory calculations since the layered MoS_(2)provides the ideal platform for the elaborating copies of the nitrogenase found in nature,wherein the functionalization is achieved via basal-adsorption,basal-substitution or edge-substitution of transition metal elements.Our results reveal that the edge-functionalization is a feasible strategy for the activity promotion;however,the basal-adsorption and basal-substitution separately suffer from the electrochemical instability and the NRR inefficiency.Specifically,MoS_(2)functionalized via edge W-substitution exhibits an exceptional activity.The energetically favored reaction pathway is through the distal pathway and a limiting potential is less than 0.20 V.Overall,this work escalates the rational design of the high-effective catalysts for nitrogen fixation and provides the explanation why the predicated catalyst have a good performance,paving the guidance for the experiments.

Current and further trajectories in designing functional materials for solid oxide electrochemical cells:A review of other reviews

Complex oxides are an important class of materials with enormous potential for electrochemical appli-cations.Depending on their composition and structure,such complex oxides can exhibit either a single conductivity(oxygen-ionic or protonic,or n-type,or p-type electronic)or a combination thereof gener-ating distinct dual-conducting or even triple-conducting materials.These properties enable their use as diverse functional materials for solid oxide fuel cells,solid oxide electrolysis cells,permeable membranes,and gas sensors.The literature review shows that the field of solid oxide materials and related electro-chemical cells has a significant level of research engagement,with over 8,000 publications published since 2020.The manual analysis of such a large volume of material is challenging.However,by examining the review articles,it is possible to identify key patterns,recent achievements,prospects,and remaining obstacles.To perform such an analysis,the present article provides,for the first time,a comprehensive summary of previous review publications that have been published since 2020,with a special focus on solid oxide materials and electrochemical systems.Thus,this study provides an important reference for researchers specializing in the fields of solid state ionics,high-temperature electrochemistry,and energyconversiontechnologies.

Sustainable Generation of Sulfate Radicals and Decontamination of Micropollutants via Sequential Electrochemistry

The removal of emerging micropollutants in the aquatic environment remains a global challenge.Conventional routes are often chemically,energetically,and operationally intensive,which decreases their sustainability during applications.Herein,we develop an advanced chemical-free strategy for micropollutants decontamination that is solely based on sequential electrochemistry involving ubiquitous sulfate anions in natural and engineered waters.This can be achieved via a chain reaction initiated by electrocatalytic anodic sulfate(SO_(4)^(2-))oxidation to produce persulfate(S_(2)O_(8)^(2-))and followed by a cathodic persulfate reduction to produce sulfate radicals(SO_(4)^(·-)).These SO_(4)^(·-)are powerful reactive species that enable the unselective degradation of micropollutants and yield SO_(4)^(2-)again in the treated water.The proposed flow-through electrochemical system achieves the efficient degradation(100.0%)and total organic carbon removal(65.0%)of aniline under optimized conditions with a single-pass mode.We also reveal the effectiveness of the proposed system for the degradation of a wide array of emerging micropollutants over a broad pH range and in complex matrices.This work provides the first proof-ofconcept demonstration using ubiquitous sulfate for micropollutants decontamination,making water purification more sustainable and more economical.

Hot electron electrochemistry at silver activated by femtosecond laser pulses

A silver microelectrode with a diameter of 30μm in an aqueous K_(2)SO_(4) electrolyte was irradiated with 55 fs and 213 fs laser pulses.This caused the emission of electrons which transiently charged the electrochemical double layer.The two applied pulse durations were significantly shorter than the electron-phonon relaxation time.The laser pulse durations had negligible impact on the emitted charge,which is incompatible with multiphoton emission.On the other hand,the ob-served dependence of emitted charge on laser fluence and electrode potential supports the thermionic emission mechanism.

Microstructure and water-swelling mechanism of red-bed mudstone in the Xining region,Northeastern Tibetan Plateau

This paper examines the effect of the microstructure and electrical conductivity(EC)on the swelling ratio and pressure in red-bed mudstone sampled from arid areas in the Xining region in the northeastern Tibetan Plateau.A series of laboratory tests,including swelling experiments,X-ray diffraction(XRD),and scanning electron microscope(SEM),was carried out for mechanical and microstructural analysis.The coupled influence of the EC and microstructural parameters on the expansion ratio and pressure was investigated,and the weight coefficients were discussed by the entropy weight method.The results revealed an increasing exponential trend in EC,and the maximum swelling speed occurred at an EC of approximately 10 μS/cm.In addition,a method for predicting the expansion potential is proposed based on the microstructure,and its reliability is verified by comparing with swelling experimental results.In addition,according to the image analysis results,the ranges of the change in the clay minerals content(CMC),the fractal dimension(FD),the average diameter(AD)of pores,and the plane porosity(PP)are 23.75%-53%,1.08-1.17,7.53-22.45 mm,and 0.62%-1.25%,respectively.Moreover,mudstone swelling is negatively correlated with the plane porosity,fractal dimension and average diameter and is linearly correlated with the clay mineral content.Furthermore,the weight values prove that the microstructural characteristics,including FD,AD,and PP,are the main factors influencing the expansion properties of red-bed mudstones in the Xining region.Based on the combination of macro and micro-analyses,a quantitative analysis of the swelling process of mudstones can provide a better reference for understanding the mechanism of expansion behavior.

气溶胶中OC和EC分离方法研究

碳质气溶胶的来源解析及其环境行为研究可以为我国的“减碳”及相关法规的制定提供必要的科学依据,是目前全球气候变化和大气环境科学研究的前沿和热点之一。本文通过氚碳氧化燃烧炉实现气溶胶样品中OC和EC的分离,建立最佳的升温程序,研究基于氚碳氧化燃烧炉的气溶胶中OC和EC分离方法。

不同营养液EC值对叶用莴苣生长及营养品质的影响

为明确营养液EC值对不同叶用莴苣品种生长和营养品质的影响,本研究采用单因素试验设计,设置3个不同营养液EC值(1.6、2.0、2.4 mS/cm),培养2种叶用莴苣,并测定其植株的农艺性状、光合指标及营养品质。结果表明:不同叶用莴苣品种对营养液EC值相应不同,当营养液EC值为1.6 mS/cm时,有利于紫霞品种的生长,表现为冠幅较大、最大叶宽较宽、光合指标较高、干物质及维生素C含量较高;当营养液EC值为2.0 mS/cm时,则有利于玛丽娜品种的生长,但营养指标较低。说明,不同叶用莴苣品种的农艺性状、光合指标及营养品质对营养液EC值反应差异较大。在叶用莴苣种植过程中,应根据叶用莴苣品种、生育期等适当调节营养液EC值,避免盲目提高营养液EC值,造成不必要的浪费。

EC细网格10 m风场产品在青岛港区的预报检验和随机森林订正

利用2021年3月—2022年2月EC细网格10 m风场预报产品,对其在青岛港区的风场预报能力进行检验和订正。结果表明:对于大港码头、董家口港自动站和董家口港浮标站,EC细网格前48 h的10 m风速预报偏差离散程度相对较小,预报偏差中位数均大于0,表明模式风速预报较实况有系统性偏强的特征。EC细网格24 h预报的10 m风速与实况风速相关性较好,3个站点的相关系数分别为0.76、0.73、0.82。EC细网格对大港码头各风向的风速预报均偏大,在实况风向为东北风和偏东风时,EC细网格风速预报的均方根误差和平均误差最大;对于董家口港自动站和董家口港浮标站,不同风向下EC细网格的风速预报均方根误差差别不大。EC细网格对3个站点的风向预报偏差主要集中在-45°~45°,实况风速越小,风向的预报偏差离散程度越大。利用随机森林算法对青岛港区EC细网格预报风速进行订正,预报精度均得到提高。

Multiple factors influencing high-purity indium electrolytic refining

The effects of various contaminants in the electrolytic refinement of indium were investigated using a glow discharge mass spectrometer(GDMS).The effects of several factors such as the indium ion(In3+)concentration,the sodium chloride(NaCl)concentration,the current density,the gelatin concentration,the pH,and the electrode distance,were examined.Significant variations in impurity levels concerning gelatin concentration were observed.Both the gelatin and In3+concentration were moderately positively correlated with the Pb content.The Sb concentration was associated positively with the NaCl concentration,while the Ti concentration had an adverse correlation with the NaCl concentration.The Bi element content was positively linked to the electrode distance.As the current density increased,Cu,Pb,and Bi impurities initially rose and then eventually declined.Notably,a critical current density of 45 A·m^(-2) was identified in this behavior.

Uncovering the electrooxidation behavior of 5-hydroxymethylfurfural on Ni/Co electrodes

Biomass,derived from plant photosynthesis that captures carbon dioxide to form carbohydrates,offers vast renewable reserves.The electrooxidation of biomass,coupled with the hydrogen evolution reaction,enables the simultaneous production of biomass-based plastic monomers and green hydrogen,attracting significant scholarly interest.However,ambiguity remains regarding the adsorption mechanism at the catalyst surface(Langmuir-Hinshelwood or Eley-Rideal)and the adsorbed substrate groups.To address this,we prepared a Ni/Co electrode for the electrooxidation of 5-hydroxymethylfurfural(HMF)into 2,5-furandicarboxylic acid(FDCA)through a corrosion reaction and electro-reduction pathway.HMF conversion reached 100.00%,FDCA yield reached 96.82%,and Faradic efficiency(FE)reached 92.14%.Meaningfully,utilizing in-situ spectroscopy and electrochemical methods,this work provided valuable insights into active sites and catalyst surface adsorption.

Advances of Electrochemical and Electrochemiluminescent Sensors Based on Covalent Organic Frameworks

Covalent organic frameworks(COFs),a rapidly developing category of crystalline conjugated organic polymers,possess highly ordered structures,large specific surface areas,stable chemical properties,and tunable pore microenvironments.Since the first report of boroxine/boronate ester-linked COFs in 2005,COFs have rapidly gained popularity,showing important application prospects in various fields,such as sensing,catalysis,separation,and energy storage.Among them,COFs-based electrochemical(EC)sensors with upgraded analytical performance are arousing extensive interest.In this review,therefore,we summarize the basic properties and the general synthesis methods of COFs used in the field of electroanalytical chemistry,with special emphasis on their usages in the fabrication of chemical sensors,ions sensors,immunosensors,and aptasensors.Notably,the emerged COFs in the electrochemiluminescence(ECL)realm are thoroughly covered along with their preliminary applications.Additionally,final conclusions on state-of-the-art COFs are provided in terms of EC and ECL sensors,as well as challenges and prospects for extending and improving the research and applications of COFs in electroanalytical chemistry.

基于儿童安全座椅的德国ADAC测试与ECE R129法规差异性研究

本文解析了德国ADAC测试与ECER129法规的主要差异,梳理了德国ADAC测试方法及评分规则,结合ECER129法规内容介绍了德国ADAC测试的主要项目,并进行了德国ADAC碰撞测试比对,期望帮助我国儿童安全座椅企业在产品设计时结合法规差异性,以在满足ECE R129法规的基础上取得更好的ADAC测试评分。

Classification and technical target of water electrolysis for hydrogen production

Continuous efforts are underway to reduce carbon emissions worldwide in response to global climate change.Water electrolysis technology,in conjunction with renewable energy,is considered the most feasible hydrogen production technology based on the viable possibility of large-scale hydrogen production and the zero-carbon-emission nature of the process.However,for hydrogen produced via water electrolysis systems to be utilized in various fields in practice,the unit cost of hydrogen production must be reduced to$1/kg H_(2).To achieve this unit cost,technical targets for water electrolysis have been suggested regarding components in the system.In this paper,the types of water electrolysis systems and the limitations of water electrolysis system components are explained.We suggest guideline with recent trend for achieving this technical target and insights for the potential utilization of water electrolysis technology.