From VIB‑to VB‑Group Transition Metal Disulfides:Structure Engineering Modulation for Superior Electromagnetic Wave Absorption

The laminated transition metal disulfides(TMDs),which are well known as typical two-dimensional(2D)semiconductive materials,possess a unique layered structure,leading to their wide-spread applications in various fields,such as catalysis,energy storage,sensing,etc.In recent years,a lot of research work on TMDs based functional materials in the fields of electromagnetic wave absorption(EMA)has been carried out.Therefore,it is of great significance to elaborate the influence of TMDs on EMA in time to speed up the application.In this review,recent advances in the development of electromagnetic wave(EMW)absorbers based on TMDs,ranging from the VIB group to the VB group are summarized.Their compositions,microstructures,electronic properties,and synthesis methods are presented in detail.Particularly,the modulation of structure engineering from the aspects of heterostructures,defects,morphologies and phases are systematically summarized,focusing on optimizing impedance matching and increasing dielectric and magnetic losses in the EMA materials with tunable EMW absorption performance.Milestones as well as the challenges are also identified to guide the design of new TMDs based dielectric EMA materials with high performance.

The design and engineering strategies of metal tellurides for advanced metal-ion batteries

Owning various crystal structures and high theoretical capacity,metal tellurides are emerging as promising electrode materials for high-performance metal-ion batteries(MBs).Since metal telluride-based MBs are quite new,fundamental issues raise regarding the energy storage mechanism and other aspects affecting electrochemical performance.Severe volume expansion,low intrinsic conductivity and slow ion diffusion kinetics jeopardize the performance of metal tellurides,so that rational design and engineering are crucial to circumvent these disadvantages.Herein,this review provides an in-depth discussion of recent investigations and progresses of metal tellurides,beginning with a critical discussion on the energy storage mechanisms of metal tellurides in various MBs.In the following,recent design and engineering strategies of metal tellurides,including morphology engineering,compositing,defect engineering and heterostructure construction,for high-performance MBs are summarized.The primary focus is to present a comprehensive understanding of the structural evolution based on the mechanism and corresponding effects of dimension control,composition,electron configuration and structural complexity on the electrochemical performance.In closing,outlooks and prospects for future development of metal tellurides are proposed.This work also highlights the promising directions of design and engineering strategies of metal tellurides with high performance and low cost.

Surface engineering of P2-type cathode material targeting long-cycling and high-rate sodium-ion batteries

The widespread interest in layered P2-type Mn-based cathode materials for sodium-ion batteries(SIBs)stems from their cost-effectiveness and abundant resources.However,the inferior cycle stability and mediocre rate performance impede their further development in practical applications.Herein,we devised a wet chemical precipitation method to deposit an amorphous aluminum phosphate(AlPO_(4),denoted as AP)protective layer onto the surface of P2-type Na_(0.55)Ni_(0.1)Co_(0.7)Mn_(0.8)O_(2)(NCM@AP).The resulting NCM@5AP electrode,with a 5 wt%coating,exhibits extended cycle life(capacity retention of78.4%after 200 cycles at 100 mA g^(-1))and superior rate performance(98 mA h g^(-1)at 500 mA g^(-1))compared to pristine NCM.Moreover,our investigation provides comprehensive insights into the phase stability and active Na^(+)ion kinetics in the NCM@5AP composite electrode,shedding light on the underlying mechanisms responsible for the enhanced performance observed in the coated electrode.

An intelligent system for calculating the scale of rational,enlarged production of an underground non-ferrous metal mine

The enlarged production scale of underground non-ferrous metal mines is affected by many uncertain factors difficult to describe mathematically with any level of accuracy.The problem can be solved by a synthesis of artificial intelligence.Based on the analysis of the major factors affecting the scale of enlarged production,we first interpreted in detail the design principles and structure of the intelligent system.Secondly,we introduced an ANN subsystem.In order to ensure technological and scale efficien- cies of the training samples for ANN,we filtrated the samples with a DEA method.Finally,we trained the intelligent system,which was proved to be very efficient.

Safety evaluation system for hydraulic metal structures based on knowledge engineering

A comprehensive safety evaluation system taking the most influential factors into account has been developed to evaluate the reliability of hydraulic metal structures. Applying the techniques of AI and DB, the idea of a one-machine and three-base system is proposed. The framework of the three-base system has been designed and the structural framework constructed in turn. A practical example is given to illustrate the process of using this system and it can be used for comparison and analysis purposes. The key technology of the system is its ability to reorganize and improve the expert system＇s knowledge base by establishing the expert system. This system utilizes the computer technology inference process, making safety evaluation conclusions more reasonable and applicable to the actual situation. The system is not only advanced, but also feasible, reliable, artificially intelligent, and has the capacity to constantly grow.

Research progress in electrospinning engineering for all-solid-state electrolytes of lithium metal batteries

Owing to safety issue and low energy density of liquid lithium-ion batteries(LIBs),all-solid-state lithium metal batteries(ASLMBs)with unique all-solid-state electrolytes(SEs)have attracted wide attentions.This arises mainly from the advantages of the SEs in the suppression of lithium dendrite growth,long cycle life,and broad working temperature range,showing huge potential applications in electronic devices,electric vehicles,smart grids,and biomedical devices.However,SEs suffer from low lithiumion conductivity and low mechanical integrity,slowing down the development of practical ASLMBs.Nanostructure engineering is of great efficiency in tuning the structure and composition of the SEs with improved lithium-ion conductivity and mechanical integrity.Among various available technologies for nanostructure engineering,electrospinning is a promising technique because of its simple operation,cost-effectiveness,and efficient integration with different components.In this review,we will first give a simple description of the electrospinning process.Then,the use of electrospinning technique in the synthesis of various SEs is summarized,for example,organic nanofibrous matrix,organic/inorganic nanofibrous matrix,and inorganic nanofibrous matrix combined with other components.The current development of the advanced architectures of SEs through electrospinning technology is also presented to provide references and ideas for designing high-performance ASLMBs.Finally,an outlook and further challenges in the preparation of advanced SEs for ASLMBs through electrospinning engineering are given.

Cross-Lingual Non-Ferrous Metals Related News Recognition Method Based on CNN with A Limited Bi-Lingual Dictionary

To acquire non-ferrous metals related news from different countries’internet,we proposed a cross-lingual non-ferrous metals related news recognition method based on CNN with a limited bilingual dictionary.Firstly,considering the lack of related language resources of non-ferrous metals,we use a limited bilingual dictionary and CCA to learn cross-lingual word vector and to represent news in different languages uniformly.Then,to improve the effect of recognition,we use a variant of the CNN to learn recognition features and construct the recognition model.The experimental results show that our proposed method acquires better results.

Optimizing Non-Ferrous Metal Value from MSWI Bottom Ashes

The bottom ashes resulted annually from the incineration of municipal solid waste in Europe contain about 400,000 tonnes of metallic aluminium and 200,000 tonnes of heavy non-ferrous metals, such as copper and zinc. Efficient recovery of this non-ferrous metal resource requires state-of-the-art separation technologies and a continuous feedback of laboratory analyses of the metal products and the depleted bottom ash to the operators of the bottom ash treatment plants. A methodology is presented for the optimization of the production of non-ferrous metal value from Municipal Solid Waste Incinerator bottom ash. Results for an incineration plant in the Netherlands show that efficient recycling can have a significant impact on value recovery as well as on non-ferrous metal recycling rates, producing up to 8% more revenue and 25% more metals from the ash.

d-d Orbital coupling induced by crystal-phase engineering assists acetonitrile electroreduction to ethylamine

The d-d orbital coupling induced by crystal-phase engineering can effectively adjust the electronic structure of electrocatalysts,thus showing significant catalytic performance,while it has been rarely explored in electrochemical acetonitrile reduction reaction(ARR)to date.Herein,we successfully realize the structural transformation of Pd Cu metallic aerogels(MAs)from face-centered cubic(FCC)to body-centered cubic(BCC)through annealing treatment.Specifically,the BCC Pd Cu MAs exhibit excellent ARR performance with high ethylamine selectivity of 90.91%,Faradaic efficiency of 88.60%,yield rate of 316.0 mmol h^(-1)g^(-1)_(Pd+Cu)and long-term stability for consecutive electrolysis within 20 h at-0.55 V vs.reversible hydrogen electrode,outperforming than those of FCC Pd Cu MAs.Under the membrane electrode assembly system,BCC Pd Cu MAs also demonstrate excellent ethylamine yield rate of 389.5 mmol h^(-1)g^(-1)_(Pd+Cu).Density functional theory calculation reveals that the d-d orbital coupling in BCC Pd Cu MAs results in an evident correlation effect for the interaction of Pd and Cu sites,which boosts up the Cu sites electronic activities to enhance ARR performance.Our work opens a new route to develop efficient ARR electrocatalysts from the perspective of crystalline structure transformation.

Scaling law of hydrogen evolution reaction for InSe monolayer with 3d transition metals doping and strain engineering

Recently, two dimensional In Se attracts great attentions as potential hydrogen production photocatalysts.Here, comprehensive investigations on the hydrogen evolution reaction activity of In Se monolayer with3 d transition metal doping and biaxial strain were performed based on the density functional theory.Transition metal dopants significantly increase the bonding strength between H and Se, and then adjust the hydrogen adsorption free energy to 0.02 e V by Zn doping. The enhanced hydrogen evolution reaction activity results from less electron occupying H 1 s-Se 4 pzanti-bonding states, which is well correlated with the pzband center level. Importantly, the universal scalling law was proposed to descript the evolution of hydrogen adsorption free energy including both doping and strain effects. Moreover, with appropriate band alignment, optical absorption, and carriers separation ability, Zn doped In Se monolayer is considered as a promising candidate of visible-light photocatalyst for hydrogen production.

Doping-induced metal–N active sites and bandgap engineering in graphitic carbon nitride for enhancing photocatalytic H_(2 )evolution performance

Durable and inexpensive graphitic carbon nitride(g-C_(3)N_(4))demonstrates great potential for achieving efficient photocatalytic hydrogen evolution reduction(HER).To further improve its activity,g-C_(3)N_(4)was subjected to atomic-level structural engineering by doping with transition metals(M=Fe,Co,or Ni),which simultaneously induced the formation of metal-N active sites in the g-C_(3)N_(4)framework and modulated the bandgap of g-C_(3)N_(4).Experiments and density functional theory calculations further verified that the as-formed metal-N bonds in M-doped g-C_(3)N_(4)acted as an"electron transfer bridge",where the migration of photo-generated electrons along the bridge enhanced the efficiency of separation of the photogenerated charges,and the optimized bandgap of g-C_(3)N_(4)afforded stronger reduction ability and wider light absorption.As a result,doping with either Fe,Co,or Ni had a positive effect on the HER activity,where Co-doped g-C_(3)N_(4)exhibited the highest performance.The findings illustrate that this atomic-level structural engineering could efficiently improve the HER activity and inspire the design of powerful photocatalysts.

Microstructure and grain boundary engineering of a novel Fe-Cr-Ni alloy weldment made with self-developed composition-matched weld filler metal

The microstructure,texture,and yield strength of an advanced heat-resistant alloy weldment made with composition-matched weld filler were investigated.Scanning electron microscopy,energy dispersive spectroscopy,and electron backscatter diffraction were used to characterize the microstructural and textural changes.Various grain boundary engineering(GBE)processes were performed on the weldment.The yield strengths of the weldment at 973 K were obtained before and after GBE processing,and were mostly consistent with the theoretically predicted values.The coincident-site lattices,misorientation,and recrystallization of the weld metal after GBE were analyzed,and the results indicate that the increase in dislocation density and the improvement in special grain boundaries in the weld metal are the main reasons for the yield strength elevation of the weldment after GBE.The variation in elongation after high-temperature tests has the same tendency as that in the impact toughness with different GBE parameters,which is related to the coarsening behavior of carbides.

Preparation and Microstructural Analysis of Smelting Waste Non-ferrous Metal Slag Geopolymer

The geopolymer samples were prepared with smelting waste slag of non-ferrous metal as the raw material and water glass as the activator. The effect of modulus of water glass and water binder ratio on the compressive strength was studied. The results show that the strength of the geopolymer activated by water glass with modulus of 1.1 and water binder ratio of 0.28 can maintain an increasing trend in the 90 curing days. Through the analyses with XRD, SEM（EDS）, and FTIR, the main reaction products are found to be geopolymer gels, which bond the crystalline minerals to provide strength. The molecular chains of amorphous phase in slag become shorter after depolymerization-polycondensation.

Recent Progress and Prospects on Dendrite-free Engineerings for Aqueous Zinc Metal Anodes

Rechargeable zinc-ion batteries with mild aqueous electrolytes are one of the most promising systems for large-scale energy storage as a result of their inherent safety,low cost,environmental-friendliness,and acceptable energy density.However,zinc metal anodes always suffer from unwanted dendrite growth,leading to low Coulombic efficiency and poor cycle stability and during the repeated plating/stripping processes,which substantially restrict their further development and application.To solve these critical issues,a lot of research works have been dedicated to overcoming the drawbacks associated with zinc metal anodes.In this overview,the working mechanisms and existing issues of the zinc metal anodes are first briefly outlined.Moreover,we look into the ongoing processes of the different strategies for achieving highly stable and dendrite-free zinc metal anodes,including crystal engineering,structural engineering,coating engineering,electrolyte engineering,and separator engineering.Finally,some challenges being faced and prospects in this field are provided,together with guiding significant research directions in the future.

Ecological environment response of benthic foraminifera to heavy metals and human engineering: A case study from Jiaozhou Bay, China

The estuary and coastal zone are the key areas for socio-economic development,and they are also the important channels for pollutants transported to the sea.The construction of the Jiaozhou Bay Bridge changed the hydrodynamic condition of the bay,which made the self-purification capacity of the bay weakened and the pollution in the estuary and adjacent coastal zone become more serious.In this study,55 surface sediment samples were collected from the three seriously polluted estuaries and the adjacent coastal zone of Jiaozhou Bay to comprehensively study how the benthic foraminifera response to heavy metal pollution and human engineering,and to assess the ecological risks of the bay.A total of 80 species,belonging to 42 genera,were identified in this study.The results showed that Cu,Pb,Cr,Hg,Zn,and As had low to median ecological risks in the study area which would definitely affect the ecological system.The construction of the Jiaozhou Bay Bridge has resulted in pollutants accumulated at the river mouth of Loushan River,which has adverse effects on the survival and growth of benthic foraminifera.The lowest population density and diversity as well as the highest FAI(Foraminiferal Abnormality Index)and FMI(Foraminiferal Monitoring Index)occurred at Loushan River Estuary which indicated that the ecological environment of the northeastern part of Jiaozhou Bay(Loushan River Estuary)had been seriously damaged.Licun River and Haipo River estuaries and the adjacent coastal zone were slightly polluted and had low ecological risk.As a consequence,it suggested that the supervision of industrial and domestic waste discharge and the protection of the ecological environment in northeast Jiaozhou Bay should be paid more attention.

Investigation into precision engineering design and development of the next-generation brake discs using Al/SiC metal matrix composites

Substantially lightweight brake discs with high wear resistance are highly desirable in the automotive industry.This paper presents an investigation of the precision-engineering design and development of automotive brake discs using nonhomogeneous Al/SiC metal-matrixcomposite materials.The design and development are based on modeling and analysis following stringent precision-engineering principles,i.e.,brake-disc systems that operate repeatably and stably over time as enabled by precision-engineering design.The design and development are further supported by tribological experimental testing and finite-element simulations.The results show the industrial feasibility of the innovative design approach and the application merits of using advanced metal-matrix-composite materials for next-generation automotive and electric vehicles.

Engineering transition metal-based nanomaterials for high-performance electrocatalysis

Transition metal(TM)based electrocatalysts attract increasing attention in energy conversion reactions,and current effects focus on material engineering strategies to tailor physicochemical properties of TM based electrocatalysts for improved performance.This review provides a summary about the recent advances of engineering TM based nanomaterials for electrocatalytic reactions,which include hydrogen evolution reaction(HER),oxygen evolution reaction(OER),CO2 reduction reaction(CO2RR),and nitrate reduction reaction(NO3RR).We highlight four engineering strategies,namely,size engineering,facet engineering,composition engineering,and crystal structure engineering for TM based electrocatalysts,and pay a special emphasis on exploring the relationship between their physicochemical properties and catalytic activities.We outline the opportunities in this research field,in particular,the strategy of rationally combining in-situ and operando techniques and theoretical predication to design efficient electrocatalysts.Finally,issues that deserve attention and consideration for practical applications are discussed.

The interfacial engineering of metal electrodes for high-specific-energy and long-lifespan batteries

High-specific-energy batteries with long-lifespan are the development aspiration for energy storage applications.Metal electrodes with high specific capacity and low reduction potential are potential candidates for next-generation high-specific-energy batteries.Nevertheless,the stability of the metal electrode batteries is constantly suffered from the unstable interface issue during the plat-ing/stripping process,such as dendrite formation,dynamic evolution of solid electrolyte interphase,and other accompanied side reactions.To solve these challenges,numerous researches have been intensively studied based on the interfacial engineering of metal electrodes,including electrode configuration optimization,interfacial chemistry regulation and solid-solid interface construc-tion,and the recent progress is elaborately introduced in this paper.Nevertheless,the dendrite issues cannot be entirely prohibited in solid metal electrodes,which motivate the search for potential alternatives.Liquid-metal electrodes with completely reversible structural changes and high mass transfer rate are rendered as an effective approach to solve the dendrite problem.Therefore,the development of liquid metal electrode batteries is reviewed in this paper,in which the interfacial issues are explicated and some commendable achievements are summarized.In the end,the implementation of interfacial engineering and the development roadmap of the metal electrode batteries are prospected.

FORMING FREEFORM SURFACE SHEET METAL USING INTEGRATED REVERSE ENGINEERING TECHNOLOGY

This paper presented a model of integrated reverse engineering system and set up its various data output flowchart, which is easy to be associated with other systems. The idea of integrated reverse engineer is introduced to the system of forming sheet metal with complex surface and using IDEF0 method sets up the function model of the system. The freeform surface reconstruction and CAD modeling of the system are described and decomposed. This paper discussed some problems, such as the feature expression, feature modeling and feature translation of the sheet parts and dies.

Non-ferrous Metal Industry in Hunan Province

In the last ten years (1982～1991) 2.26 Mt of 10 kinds of nonferrous metals had been pro-duced in Hunan Province. Up to date the mining capacity achieves 6.52 Mt, ore-dressing capacity--7.25 Mt, smelt capacity--334 kt and the processing capacity--113 kt. In 1991 the output of10 kinds of nonferrous metals amounted to 292.8 kt. At present Hunan Province produces alloys,oxides and other compounds for copper, aluminium, lead, zinc, antimony and mercury. Species ofrare-earth metals and its alloys produced in Hunan Province amount to 160 and more. In this