Disordered Structure and Reversible Phase Transformation from K-Birnessite to Zn-Buserite Enable High-Performance Aqueous Zinc-lon Batteries

The layeredδ-MnO_(2)(dMO)is an excellent cathode material for rechargeable aqueous zinc-ion batteries owing to its large interlayer distance(~0.7 nm),high capacity,and low cost;however,such cathodes suffer from structural degradation during the long-term cycling process,leading to capacity fading.In this study,a Co-doped dMO composite with reduced graphene oxide(GC-dMO)is developed using a simple cost-effective hydrothermal method.The degree of disorderness increases owing to the hetero-atom doping and graphene oxide composites.It is demonstrated that layered dMO and GC-dMO undergo a structural transition from K-birnessite to the Zn-buserite phase upon the first discharge,which enhances the intercalation of Zn^(2+)ions,H_(2)O molecules in the layered structure.The GC-dMO cathode exhibits an excellent capacity of 302 mAh g^(-1)at a current density of 100 mAg^(-1)after 100 cycles as compared with the dMO cathode(159 mAhg^(-1)).The excellent electrochemical performance of the GC-dMO cathode owing to Co-doping and graphene oxide sheets enhances the interlayer gap and disorderness,and maintains structural stability,which facilitates the easy reverse intercalation and de-intercalation of Zn^(2+)ions and H_(2)O molecules.Therefore,GC-dMO is a promising cathode material for large-scale aqueous ZIBs.

Microearthquake reveals the lithospheric structure at midocean ridges and oceanic transform faults

Mid-ocean ridge and oceanic transforms are among the most prominent features on the seafloor surface and are crucial for understanding seafloor spreading and plate tectonic dynamics,but the deep structure of the oceanic lithosphere remains poorly understood.The large number of microearthquakes occurring along ridges and transforms provide valuable information for gaining an indepth view of the underlying detailed seismic structures,contributing to understanding geodynamic processes within the oceanic lithosphere.Previous studies have indicated that the maximum depth of microseismicity is controlled by the 600-℃isotherm.However,this perspective is being challenged due to increasing observations of deep earthquakes that far exceed this suggested isotherm along mid-ocean ridges and oceanic transform faults.Several mechanisms have been proposed to explain these deep events,and we suggest that local geodynamic processes(e.g.,magma supply,mylonite shear zone,longlived faults,hydrothermal vents,etc.)likely play a more important role than previously thought.

Anomaly Detection Algorithm of Power System Based on Graph Structure and Anomaly Attention

In this paper, we propose a novel anomaly detection method for data centers based on a combination of graphstructure and abnormal attention mechanism. The method leverages the sensor monitoring data from targetpower substations to construct multidimensional time series. These time series are subsequently transformed intograph structures, and corresponding adjacency matrices are obtained. By incorporating the adjacency matricesand additional weights associated with the graph structure, an aggregation matrix is derived. The aggregationmatrix is then fed into a pre-trained graph convolutional neural network (GCN) to extract graph structure features.Moreover, both themultidimensional time series segments and the graph structure features are inputted into a pretrainedanomaly detectionmodel, resulting in corresponding anomaly detection results that help identify abnormaldata. The anomaly detection model consists of a multi-level encoder-decoder module, wherein each level includesa transformer encoder and decoder based on correlation differences. The attention module in the encoding layeradopts an abnormal attention module with a dual-branch structure. Experimental results demonstrate that ourproposed method significantly improves the accuracy and stability of anomaly detection.

Performance Evaluation of Low-Carbon and Clean Transformation of China’s Coal Economy

In China,the oversupply of coal occurred in 2009,and from that year onwards,China’s coal economy began a low-carbon and clean transformation.Evaluating transformation performance is the research goal of this paper.The data collection for this paper includes data on deep processing of Chinese coal products from 2009 to 2020,as well as data on asset structure evolution and financial performance of 34 listed companies in the Chinese coal mining.Entropy value method is used to calculate the entropy value of low-carbon transformation,and the regression analysis is used to study the performance of cleaner transformation,the conclusion is as follows:(1)From 2009 to 2020,in China’s total energy consumption,coal consumption accounted for 71.6%in 2009 and 56.8%in 2020,the goals set by the state have been achieved.(2)The national goal of reducing the proportion of coal consumption and reducing carbon emissions has forced the transformation of deep processing of coal products.The transformation of coal enterprises towards low-carbon and clean production has achieved remarkable results.(3)From 2009 to 2020,the non coal industry income of 34 listed companies in China’s coal mining industry increased by 8.21%annually.At the same time,the asset structure was adjusted,and nearly 80%of the asset structure evolution showed an orderly development trend.(4)The regression analysis results show that the entropy value of coal deep processing products and the entropy value of asset structure adjustment are significantly related to transformation performance.The paper proposes to summarize the successful experience of China’s coal energy economic transformation,lay a foundation for achieving the carbon peak and carbon neutral goals in the future,further increase the intensity of coal deep processing,increase the proportion of clean energy in total energy consumption,and strive to control asset operation towards the goal of increasing the proportion of non coal industry income.

Effectiveness of Land Use Structure Evolution to Industrial Structure Transformation

Scarcity of land resources and transformation of industrial structure is a pair of contradictory elements.We derive the characteristics of land use structure and industrial structure transformation in Xining City using Transformation Coefficient(TC):first,in the period 1999-2000,the land use structure coefficient(θ1) declined by 79.55%,but the overall evolution trend is gentle;second,the transformation coefficient of industrial structure(θ2) tended to decline ceaselessly on the whole,a decrease of 36.09%(overall,the transformation coefficient of industrial structure is slightly greater than the land use structure coefficient);third,the inter-annual variation of the two experienced ups and downs(in the period 1999-2007,the inter-annual variation was great and in the period 2008-2010,the inter-annual variation tended to be gentle).On the basis of autocorrelation and co-integration model,we draw the following conclusions through analysis:first,the land use structure in Xining City plays a role in promoting industrial structure transformation;second,there is a long-term equilibrium relationship between the two.Finally,relevant policy recommendations are put forward for the industrial development in Xining City.

Economic Structure Transformation and Land Use Change of the Changjiang River Basin

Land, as a key factor of production, is an appropriate indicator of national and regional economic structure transformation. Land use in the Changjiang （Yangtze） River Basin （CRB） since the 1950s has experienced these changes. Industrialization has been the most powerful force of the change in the regional development of the CRB. Virtually all regional resources were put into this effort to modernize the industrial production and urban construction systems of the CRB whose industrialization and urbanization has been a success story, with impressive structural change in both production and land use. These changes are evident ih modem urban areas, but even more in traditionally rural areas. The regression analysis of regional development in the CRB over an extended period shows that the dominant factor in regional land use change is widespread industrialization in rural areas rather than the expansion of urban area. Thus, urbanization has had a limited influence on land use change in the CRB. A major task in realizing more sustainable land use in the future development of CRB is to relocate industrial activities from rural to urban areas.

Synthesis and Structure Transformation of Orthorhombic LiMnO2 Cathode Materials by Sol-gel Method

Orthorhombic LiMnO2 cathode materials were synthesized successfully at lower temperature by sol-gel method. When LiMnO2 precursor prepared by sol-gel method was fired in air, the product was a mixture of spinel structure LiMn2O4 and rock-salt structure Li2MnO3, whereas in argon single-phase orthorhombic LiMnO2 could obtain at the range of 750℃ to 920℃. The substitution of Mn by Zn2+ or Co3+ in LiMnO2 led to the structure of LiMnO2 transiting to Qα-LiFeO2. The results of electrochemical cycles indicated that the discharged capacity of orthorhombic-LiMnO2 was smaller at the initial stages, then gradually increased with the increasing of cycle number, finally the capacity stabilized to certain value after about 10th cycles. This phenomenon reveals that there is an activation process for orthorhombic LiMnO2 cathode materials during electrochemical cycles, which is a phase transition process from orthorhombic LiMnO2 to tetragonal spinel Li2Mn2O4. The capacity of orthorhombic LiMnO2 synthesized at lower temperature is larger than that synthesized at high temperature.

Spatial-temporal Heterogeneity of Industrial Structure Transformation and Carbon Emission Effects in Xuzhou Metropolitan Area

Employing decoupling index and industrial structure characteristic bias index methods, this study analyzed the spatial-temporal characteristics of industrial structure transformations and their resulting carbon emissions in the Xuzhou Metropolitan Area from 2000 to 2014, with a focus on their relationships and driving factors. Our research indicates that carbon emission intensity from industrial structures in the Xuzhou Metropolitan Area at first showed an increasing trend, which then decreased. Furthermore, the relationship between emissions and industrial economic growth has been trending toward absolute decoupling. From the perspective of the center-periphery, the Xuzhou Metropolitan Area formed a concentric pattern, where both progress towards low emissions and the level of technological advancement gradually diminished from the center to the periphery. In terms of variation across provinces, the ISCB index in the eastern Henan has decreased the slowest, followed by the southern Shandong and the northern Anhui, with the northern Jiangsu ranking last. During this period, resource-and labor-intensive industries were the primary growth industries in the northern Anhui and the eastern Henan, while labor-intensive industries dominated the southern Shandong and capital-intensive industries dominated the northern Jiangsu. In terms of city types, the spatial pattern for industrial structure indicates that recession resource-based cities had higher carbon emission intensities than mature resource-based cities, followed by non-resource-based cities and regenerative resource-based cities. Generally, the industrial structure in the Xuzhou Metropolitan Area has transformed from being resource-intensive to capital-intensive, and has been trending toward technology-intensive as resource availability has been exploited to exhaustion and then been regenerated. Industrial structure has been the leading factor causing heterogeneity of carbon emission intensities between metropolitan cities. Therefore, the key to optimizing the industrial structure and layout of metropolitan areas is to promote industrial structure transformation and improve the system controlling collaborative industrial development between cities.

MICROSTRUCTURE TRANSFORMATION IN THE WELDING HEAT AFFECTED ZONE OF 800MPa GRADE ULTRA FINE STRUCTURED STEEL

The transformation behavior and microstructure development in the heat affected zone(HAZ)of 800MPa grade ultra fine structured steel was investigated.It was found that the HAZ has intermediate temperature transformation characteristics in a wide range of cooling rates,with the bainite sheaves consisting of bainite ferrite plates without carbide precipitation and retained austenite in the fast cooling regime.At relatively high cooling rates,which corresponded to low heat inputs,the hardness of the simulated HAZ was above that of the base metal.When the cooling rate was below 9C/s,the welding HAZ would have an obvious softening.The analysis of transformation rates in continuous cooling processes was completed by numerical differential method.The result indicated that the microstructure transformation rate of the HAZ in 800MPa grade ultra fine structured steel changed sharply to slow speeds when the cooling time t8/5 is longer than 7s.

Novel mechanical behavior of periodic structure with the pattern transformation

Abstract In periodic cellular structures, novel pattern transformations are triggered by a reversible elastic instability under the axial compression. Based on the deformation-triggered new pattern, periodic cellular structures can achieve special mechanical properties. In this paper, the designed architecture materials which include elastomer matrixes containing empty holes or filled holes with hydrogel material are modeled and simulated to investigate the mechanical property of the periodic materials. By analyzing the relationship between nominal stress and nominal strain of periodic material, and the corresponding deformed patterns, the influence of geometry and shapes of the holes on the mechanical property of architecture material is studied in more details. We hope this study can provide future perspectives for the deformation-triggered periodic structures.

Characteristic Functional Structure of Infinitesimal Symmetry Transformations for Nonholonomic System

It was proved that velocity-dependent infinitesima l symmetry transformations of nonholonomic systems have a characteristic functio nal structure, which could be formulated by means of an auxiliary symmetry tra nsformation function and is manifestly dependent upon constants of motion of th e system. An example was given to illustrate the applicability of the results.

Bcklund Transformation and Localized Coherent Structure for the (2+1)-Dimensional Asymmetric Nizhnik-Novikov-Veselov Equation

This article is concerned with the extended homogeneous balance method for studying the abundant localized solution structure of the (2+1) dimensional asymmetric Nizhnik Novikov Veselov equation. A B a¨ cklund transformation was first obtained, and then the richness of the localized coherent structures was found, which was caused by the entrance of two variable separated arbitrary functions, in the model. For some special choices of the arbitrary functions, it is shown that the localized structures of the model may be dromions, lumps, and ring solitons.

MORPHOLOGY AND STRUCTURE OF TRANSFORMATION PRODUCTS FORMED AT INTERMEDIATE TEMPERATURE IN A Cu-Zn-Al ALLOY

A TTT diagram for th ie precipitation formed at some intermediate temperatures through cooling from high lemperalure parenl phase in a Cu-27 27Zn-3.73Al allay is established by means of dilatormetric measurement.The morphology and structure of transformation products formed at some intermediate tem peratures isothermally through cooling from high temperature parent phase and up-quenching from DO_(3) parent phase are studied by metallographic.X-ray and electron microscopy analyses.Three regions in the two separate C curves are obtained according to different morphology of precipitate:rod-like a,plate-like bainite and a rods,and bainite plates.Prolonged aging makes bainite plate change gradually into a whose lattice parameters are no different from that of a formed equilibriumly from parent phase.The structure is almost orthorhombic long period structure for bainites formed from B_(2) and DO_(3) parent phase,but monoclinic for martensite from DO_(3).They correspond to the overlapping and separating of(1210)and(2010)diffraction peaks respectively,showing the lower degree of ordering in bainite.

Recognition of vortex structures in turbulent refractive index field using wavelet transformation

When the light wave propagates through the hypersonic flow field, the aero-optic distortion happens. It is necessary to recognize the vortex structure for studying the light propagation model. A new vortex structure recognition method is proposed in this paper. Firstly, the refractive index field, which is transformed from the turbulent density field, is changed to gray scale images with a- bundant texture information equivalently. Then, wavelet transform is performed to decompose these images and the entropy values of the wavelet base coefficients are calculated. Comparing the entropy value to a given threshold, the modules with lower entropy are considered to be the large-scale vortex modules while those with higher entropy are small-scale vortex modules. The computer simulation results show that the proposed method is valid to recognize the vortex structures. This paper provides basis for investigation on the optics propagation model in terms of the turbulence vortex structures.

Reverse-transformation austenite structure control with micro/nanometer size

To control the reverse-transformation austenite structure through manipulation of the micro/nanometer grain structure, the influences of cold deformation and annealing parameters on the microstructure evolution and mechanical properties of 316L austenitic stainless steel were investigated. The samples were first cold-rolled, and then samples deformed to different extents were annealed at different temperatures. The microstructure evolutions were analyzed by optical microscopy, scanning electron microscopy (SEM), magnetic measurements, and X-ray diffraction (XRD); the mechanical properties are also determined by tensile tests. The results showed that the fraction of stain-induced martensite was approximately 72% in the 90% cold-rolled steel. The micro/nanometric microstructure was obtained after reversion annealing at 820-870A degrees C for 60 s. Nearly 100% reversed austenite was obtained in samples annealed at 850A degrees C, where grains with a diameter ae<currency> 500 nm accounted for 30% and those with a diameter > 0.5 mu m accounted for 70%. The micro/nanometer-grain steel exhibited not only a high strength level (approximately 959 MPa) but also a desirable elongation of approximately 45%.

Hamiltonian structure, Darboux transformation for a soliton hierarchy associated with Lie algebra so(4, C)

In this paper, we first introduce a Lie algebra of the special orthogonal group, g = so(4, C), whose elements are 4 × 4trace-free, skew-symmetric complex matrices. As its application, we obtain a new soliton hierarchy which is reduced to AKNS hierarchy and present its bi-Hamiltonian structure and Liouville integrability. Furthermore, for one of the equations in the resulting hierarchy, we construct a Darboux matrix T depending on the spectral parameter λ.

Urban structure transformation of Lhasa City after the peaceful liberation and democratic reform of Tibet

In Tibet, Buddhism coupled with its theocratic history has given its cities and urban areas unique forms and structures. As the political, religious, and economic center of Tibet, Lhasa City has a special urban form and has experienced typical urban transformation processes for a thousand years. The city has been experiencing significant urban structure transformation that has accompanied the socio-economic development in recent decades since the peaceful liberation and democratic reform of Tibet during the 1950 s. Hence, this study presents the time-series of urban structure changes in Lhasa City for the purpose of understanding the characteristics and mechanisms of transformation under the republican political system. First, the study illustrates the urban socio-economic changes of Lhasa City beginning in the 1950 s via statistical data analysis. We then divide the urban development into several stages. Subsequently, we identify the transformation characteristics of urban structure by investigating urban growth, street structure, land-use, and religious facilities via maps of the city from every development stage. This paper ultimately discusses the regulation of city transformation. This study clarifies several probable issues facing Tibetan cities and proposes suggestions for future urban development of Tibetan cities.

PHASE TRANSFORMATION BEHAVIOR AND MICROSTRUCTURE OBSERVATION OF Nb-Ru HIGH TEMPERATURE SHAPE MEMORY ALLOY

The phase transformation behavior and micro structure of Nb-Ru alloys have been studied by DSC, X-ray diffraction, optical microscopy, transmission electron microscopy (TEM) and high-resolution electron microscopy (HREM). Two-step phase transformation of CsCl (β) →face-centered tetragonal (β)→ monoclinic (β') occurs during cooling from high temperature to room temperature. The lattice parameters of marten-sites of Nb-Ru alloys were found to increase with the increase of Nb content. The martensite variants exhibit triangular self-accommodating morphology, with alternating regular bands inside. The twinning relationship between the sub structural bands was found to be (101) type I mode, and this kind of twinning interface was straight, well-defined and coherent.

Finite symmetry transformation group and localized structures of the (2+1)-dimensional coupled Burgers equation

In this paper, the finite symmetry transformation group of the （2＋1）-dimensional coupled Burgers equation is studied by the modified direct method, and with the help of the truncated Painleve′ expansion approach, some special localized structures for the （2＋1）-dimensional coupled Burgers equation are obtained, in particular, the dromion-like and solitoff-like structures.

Phase Transformation in the Infinite Layer Structure Compound (Sr, Nd) CuO_(2) and its Effect on Superconductivity

Superconducting compound (Sr_(0.86)Nd_(0.14))CuO_(2 )with the infinite layer structure was synthesized under high pressure.This tetragonal structure a×a transforms into a superstructure 2√2a ×2√2a when the sample was in situ heated in transmission electron microscope to about 600K.An anormalous resistance change of the sample during heating in vacuum to 400℃ confinned the phase transformation.Aftrer the superlattice formationf the sample lost its superconductivity and became semiconducting.