The effect of Ti and Zr content on the structure,mechanics and energy-release characteristics of Ti—Zr—Ta alloys

Energetic structural materials(ESMs)are a new type of structural materials with bearing and damage characteristics.In this work the microstructure,mechanical properties and energy release characteristics of multi-element Ti-Zr-Ta alloys with good casting performance were studied.The microstructure of the Ti_(x)ZrTa alloys gradually change from BCC+HCP to single BCC structure with the increase of Ti.While the Ti_(2)Zr_(y)Ta alloys was still uniform and single BCC structure with the increase of Zr.The evolution of microstructure and composition then greatly affect the mechanical properties and energy-release characteristics of Ti-Zr-Ta alloys.The synergistic effect of dual phase structure increases the fracture strain of Ti_(x)ZrTa(x=0.2,0.5)with the Ti content decreases,while the fracture strain of Ti_(x)ZrTa(x=2.0,3.0,4.0)gradually increase with the Ti content increases caused by the annihilation of the obstacles for dislocation movement.And as Zr content increases,the fracture strain of Ti_(2)Zr_(y)Ta alloys decrease,then the oxidation reaction rate and fragmentation degree gradually increase.The higher oxidation rate and the lager exposed oxidation area jointly leads the higher releasing energy efficiency of Ti_(x)ZrTa alloys with low Ti content and Ti_(2)Zr_(y)Ta alloys with high Zr content.

Experimental study of the effects of a multistage pore-throat structure on the seepage characteristics of sandstones in the Beibuwan Basin:Insights into the flooding mode

To investigate the relationship between grain sizes, seepage capacity, and oil-displacement efficiency in the Liushagang Formation of the Beibuwan Basin, this study identifies the multistage pore-throat structure as a crucial factor through a comparison of oil displacement in microscopic pore-throat experiments. The two-phase flow evaluation method based on the Li-Horne model is utilized to effectively characterize and quantify the seepage characteristics of different reservoirs, closely relating them to the distribution of microscopic pores and throats. It is observed that conglomerate sandstones at different stages exhibit significant heterogeneity and noticeable differences in seepage capacity, highlighting the crucial role played by certain large pore throats in determining seepage capacity and oil displacement efficiency. Furthermore, it was found that the displacement effects of conglomeratic sandstones with strong heterogeneity were inferior to those of conventional homogeneous sandstone, as evidenced by multiple displacement experiments conducted on core samples with varying granularities and flooding systems. Subsequently, core-based experiments on associated gas flooding after water flooding were conducted to address the challenge of achieving satisfactory results in a single displacement mode for reservoirs with significant heterogeneity. The results indicate that the oil recovery rates for associated gas flooding after water flooding increased by 7.3%-16.4% compared with water flooding alone at a gas-oil ratio of approximately 7000 m^(3)/m^(3). Therefore, considering the advantages of gas flooding in terms of seepage capacity, oil exchange ratio, and the potential for two-phase production, gas flooding is recommended as an energy supplement mode for homogeneous reservoirs in the presence of sufficient gas source and appropriate tectonic angle. On the other hand, associated gas flooding after water flooding is suggested to achieve a more favorable development effect compared to a single mode of energy supplementation for strongly heterogeneous sandstone reservoirs.

Characteristics of geological structures in Shiling and Zhuanshanhu areas of Yehe Uplift,NE China

The basin marginal fault system is the key to understand the formation and evolution of Songliao Basin.In order to investigate the influence of marginal fault system on the structural evolution of Songliao Basin,a comprehensive study was conducted on Shiling Town and Zhuanshanhu area of Yehe Town in Siping City of Jilin Province,where is the southeastern margin of the Songliao Basin and there are a series of well-exposed fault,fold and intrusive bodies belonging to the main marginal fault system of the Songliao Basin known as the Jiamusi-Yitong(Jia-Yi)fault zone.Through profile measurement and field investigation,samples with various lithologies and distinctive features were collected.Detailed field and laboratory works include component and microstructure analysis of these samples,rock-rock contact analysis,main strike measurement and statistics analysis.These data reveal the structural characteristics of the fold,fault and intrusive bodies in the study area.The research results show that the folds are distributed in the Mesozoic strata near the main fault of the eastern branch of the Jia-Yi fault zone,and the folded strata involve the Cretaceous Denglouku and Quantou formations.In addition,the section is dominated by high-angle strikeslip thrust faults.Light-colored veins and dark-colored veins are extensively distributed in the exposed granites.Statistical analysis of joint and fault attitudes in the study area reveals a right-lateral strike-sliping along the main fault.The large-scale right-lateral strike-slip and thrust fault system in Shiling Town occurred in right-lateral transpressive stage in Late Cretaceous.Based on the results above,tectonic evolution sequence in Shiling section of the Jia-Yi fault zone during the Mesozoic can be divided into five stages:Middle Jurassic left-lateral ductile strike-slip stage,Late Jurassic compression stage,Early Cretaceous tension stage,Early Cretaceous extension stage and Late Cretaceous right-lateral transpressive stage.These may have important constraint on understanding the Mesozoic evolution of the Songliao Basin.

Structural Characteristics and Evolution of a Weighted Sino-US Container Shipping Network

This study selected the Sino-US route data from the top 30 global container liner companies between December 1,2019,and December 29,2019,as the data source utilizing the complex network research methodology.It constructs a Sino-US container shipping network through voyage weighting and analyzes the essential structural characteristics to explore the network’s complex structural fea-tures.The network’s evolution is examined from three perspectives,namely,time,space,and event influence,aiming to comprehens-ively explore the network’s evolution mechanism.The results revealed that:1)the weighted Sino-US container shipping network exhib-its small-world and scale-free properties.Key hub ports in the United States include NEW YORK NY,SAVANNAH GA,LOS ANGELES CA,and OAKLAND CA,whereas SHANGHAI serving as the hub port in China.The geographical distribution of these hub ports is uneven.2)Concerning the evolution of the weighted Sino-US container shipping network,from a temporal perspective,the evolution of the regional structure of the entire Sino-US region and the Inland United States is in a stage of radiative expansion and de-velopment,with a need for further enhancement in competitiveness and development speed.The evolution of the regional structure of southern China and Europe is transitioning from the stage of radiative expansion and development to an advanced equilibrium stage.The shipping development in Northern China,the Western and Eastern United States,and Asia is undergoing significant changes but faces challenges of fierce competition and imbalances.From a spatial perspective,the rationality and effectiveness of the improved weighted Barrat-Barthelemy-Vespignani(BBV)model are confirmed through theoretical derivation.The applicability of the improved evolution model is verified by simulating the evolution of the weighted Sino-US container shipping network.From an event impact per-spective,the Corona Virus Disease 2019(COVID-19)pandemic has not fundamentally affected the spatial pattern of the weighted Sino-US container shipping network but has significantly impacted the network’s connectivity.The network lacks sufficient resilience and stability in emergency situations.3)Based on the analysis of the structural characteristics and evolution of the weighted Sino-US con-tainer shipping network,recommendations for network development are proposed from three aspects:emphasizing the development of hub ports,focusing on the balanced development of the network,and optimizing the layout of Chinese ports.

Structure Refinement of Cs-rich Na-Li Beryl and Analysis of Its Typomorphic Characteristics of Configurations

The tabular beryl found in Huya Country, Sichuan Province is a rare and special member among beryls. Chemical analysis reveals that the beryl is a new type of Cs-rich Na-Li beryl, and the content of alkalis （Li20, Na2O, K2O, Rb2O, Cs2O） is up to 2.41%. The CCD system on the SMART APEX four circle single crystal diffractometer was used in this experiment to determine the structure of the sample accurately. The beryl belongs to the hexagonal system; its space group is P6/mcc. The dimensions of the unit cell are as follows： a = 0.91961（3） nm, c = 0.91969（7） nm, c/a = 1.0000, V= 0.67357 nm3, 7 = 120°, α= 90°, β = 90°. The accurate atomic coordinates of alkali metal ions and other crystallographic parameters are also obtained： Z = 2, the calculated density D = 2.754 g/cm^3 and final R （ I 〉 2 σ （/3）= 0.046 for 5597 reflections. The crystal structure was described by coordination polyhedron. Based on the data gained, a three-dimensional graph of the crystal structure of tabular beryl was made with the ATOMS 6.0 software. The refinement of crystal structure indicates that there are two main reasons for the cause of the tabular configuration： （1） The substitution of Be by Li into the tetrahedral framework weakened the stacked six-sided rings [Si6O18]^12- of the tetrahedral Si; （2） Alkalis （mainly Na and Cs） are too large to substitute in four-fold or six-fold coordination within the structure and are accommodated in the vacant channel. The accommodation of these alkalis strengthened the structure of six-sided rings of the tetrahedral Si. And other alkali metal ions and free volatile molecules such as H2O and CO2 occupy variable positions in the channel. The equation of the electrovalence is Li＋＋Na＋→Be^2＋. According to structural and compositional differences, the monoclinic crystal of tabular beryl is considered to be a new member of the beryl group. Chemical constraints of the environment, namely, the bulk-rock chemistry and the fluid-phase composition and physical-chemical conditions during the growth of the mineral may account for these occurrences of rare elements. In addition, that Li and Be have appro^mate physical parameters is also the key factor for the substitution. The direction of the mineralized hydrothermal liquid and the special occurrence conditions of the beryl such as the pH, temperature and pressure are also considered to be the main causes of the configuration of the tabular beryl.

Sintering characteristics of fluxes and their structure optimization

Sintering characteristics of common fluxes and sintering blending ores, such as mineralization capacity, liquid generation capacity, consolidation strength, were examined to master the behavior and effect of fluxes in sintering. Based on fundamental studies, sinter pot tests were carried out to obtain the principles of optimizing the sinter flux structure. The results showed that strong mineralization capacity, liquid phase generation capacity, and consolidation strength were obtained as sintering blending ores combined with the calcareous flux, while rela-tively poor sintering characteristics were obtained as sintering blending ores combined with the magnesian flux. High reactive quicklime should be used as much as possible in the sintering mixture. It reached better sintering results while quicklime was used instead of limestone and its appropriate proportion in the sintering mixture was around 4wt%. On the premise of ensuring the MgO content, the dolomite amount should be decreased, and the substitution of quicklime for dolomite caused better sintering results. The granularity of serpentine should be re-fined with a proper size smaller than 2 mm. The application of the divided addition method brought the best sintering performance with 30wt% of quicklime and 70wt% of fuel.

Seasonal characteristics and formation mechanism of the thermohaline structure of mesoscale eddy in the South China Sea

The seasonal characteristics and formation mechanism of the thermohaline structure of mesoscale eddy in the South China Sea are investigated using the latest eddy dataset and ARMOR3D data. Eddy-centric composites reveal that the horizontal distribution of temperature anomaly associated with eddy in winter is more of a dipole pattern in upper 50 m and tends to be centrosymmetric below 50 m, while in summer the distribution pattern is centrosymmetric in the entire water column. The horizontal distribution of eddy-induced salinity anomaly exhibits similar seasonal characteristics, except that the asymmetry of the salinity anomaly is weaker. The vertical distribution of temperature anomaly associated with eddy shows a monolayer structure, while the salinity anomaly demonstrates a triple-layer structure. Further analysis indicates that the vertical distribution of the anomalies is related to the vertical structure of background temperature and salinity fields, and the asymmetry of the anomalies in upper 50 m is mainly caused by the horizontal advection of background temperature and salinity.

Molecular characteristics and structure–activity relationships of food-derived bioactive peptides

Peptides are functional active fragments of proteins which can provide nutrients needed for human growth and development,and they also have unique physiological activity characteristics relative to proteins.Bioactive peptides contain a great deal of development potential.More specifically,food-derived bioactive peptides have the advantages of a wide variety of sources,unique structures,high efficiency and safety,so they have broad development prospects.This review provides an overview of the current advances regarding the preparation,functional characteristics,and structure–activity relationships of food-derived bioactive peptides.Moreover,the prospects for the future development and application of food-derived bioactive peptides are discussed.This review may provide a better understanding of foodderived bioactive peptides,and some constructive inspirations for further research and applications in the food industry.

Denoising of Chinese calligraphy tablet images based on run-length statistics and structure characteristic of character strokes

In this paper, a novel approach is proposed for denoising of Chinese calligraphy tablet documents. The method includes two phases: First, a partial differential equations (PDE) based the total variation model and Otsu thresholding method are used to preprocess the calligraphy document image. Second, a new method based on run-length statistics and structure charac- teristics of Chinese characters is proposed to remove some random and ant-like noises. This includes the optimal threshold se- lection from histogram of run-length probability density, and improved Hough transform algorithm for line shape noise detection and removal. Examples are given in the paper to demonstrate the proposed method.

Different characteristics of the structure of atmospheric boundary layer between dry and rainy periods over the northern Tibetan Plateau

In this paper, based on in-situ observational data of the Coordinated Enhanced Observing Period （CEOP） Asia-Australia Monsoon Project （CAMP） on the Tibetan＇Plateau （CAMP-Tibet）, structure of the Atmospheric Boundary Layer （ABL） was preliminarily studied during the dry and rainy seasons. The main results show： （a） Diurnal variation of the ABL is obvious over the northern Tibetan Plateau area. The height of the ABL is different with the season change, which ranges from 2,211 m to 4,430 m during the pre-monsoon season and from 1,006 m to 2,212 m during the monsoon season. The ABL height is higher during the dry period than during the rainyigeriod. （b） The humidity is lower during the dry period than during the rainy period, and there are reverse humidity during both periods. （c） Horizontal wind direction is mostly west during the dry period, east under the height of 2,500 m and west above the height of 2,500 m during the rainy period. The wind speed is low during both the rainy and dry periods in the lower ABL layer. The wind speed is stronger within the upper ABL during the dry period than dtn-ing the rainy period.

Near-surface structure and energy characteristics of the Antarctic Circumpolar Current

Historical surface drifter observations collected from the Southern Ocean are used to study the near-surface structure, variability, and energy characteristics of the Antarctic Circumpolar Current （ACC）. A strong, nearly zonal ACC combined with complex fronts dominates the circulation system in the Southern Ocean. Standard variance ellipses indicate that both the Agulhas Return Current and the East Australian Warm Current are stable supplements of the near-surface ACC, and that the anticyclonic gyre formed by the Brazil warm current and the Malvinas cold current is stable throughout the year. During austral winter, the current velocity increases because of the enhanced westerly wind. Aroused by the meridional motion of the ACC, the meridional velocity shows greater instability characteristics than the zonal velocity does over the core current. Additionally, the ACC exhibits an eastward declining trend in the core current velocity from southern Africa. The characteristics of the ACC are also argued from the perspective of energy. The energy distribution suggests that the mean kinetic energy （MKE）, eddy kinetic energy （EKE）, and are strong over the core currents of the ACC. However, in contrast, EKE/MKE suggests there is much less （more） eddy dissipation in regions with strong （weak） energy distribution. Both meridional and zonal energy variations are studied to illustrate additional details of the ACC energy characteristics. Generally, all the energy forms except EKE/MKE present west-east reducing trends, which coincide with the velocity statistics. Eddy dissipation has a much greater effect on MKE in the northern part of the Southern Ocean.

Effect of cermet substrate characteristics on the microstructure and properties of TiAlN coatings

The composition and structure of substrate materials have important influences on coating performance,especially in terms of bond-ing strength and coating hardness,which determine whether the coating can be used for a given application.In this study,a TiAlN coating is deposited on Ti(C,N)-based cermet(TC)substrates with 0wt%-20wt%WC by arc ion plating.The influence of cermet substrate characterist-ics on the structure and properties of the TiAlN coating is then researched.Results show that the TiAlN coating deposited on the TC substrate has a columnar grain structure.As WC increases,the strength ratio of I(111)/I(200)and adhesive strength of TiAlN gradually increases.In the ab-sence of WC in the substrate,the preferred orientation of the TiAlN coating is(200).As WC increases,the preferred orientation of the TiAlN coating becomes(111)and(200).Notable differences in adhesive strength between the coating and substrate could be attributed to the micro-structure and composition of the latter.Scratching results show that the adhesive strengths of the TiAlN coating on the 0wt%-20wt%WC cer-met substrate are 52-65 N.Among the coatings obtained that on the TC substrate with 15wt%WC presents the highest H/E and H3/E2,which indicates that this coating also features the best wear resistance.The failure mechanisms of the coated tools include coating peeling,adhesive wear,and abrasive wear.As the cutting speed increases,the degree of flank wear increases and the durability of the coating decreases accord-ingly.Increases in WC result in an initial decrease followed by a gradual increase in the flank wear of the coated cermet inserts.

Hydration Characteristics and Microstructure of Alkali-Activated Slag Concrete: A Review

Alkali-activated slag concrete (AASC) is a new green building material. The amount of CO_(2) produced by AASC is 1/5th of that produced by ordinary Portland cement concrete (OPCC). In addition, AASC promotes the reuse of slag and other wastes and saves resources. Furthermore, the scope of use of slag has been expanded. The progress of the research on the hydration characteristics, microstructure, interfacial transition zone, and pore structure of AASC based on the relevant literatures was analyzed and summarized in this study. The influences of the slag composition, the type and dosage of the alkali activator, and the curing conditions on the hydration characteristics and the microstructure of the AASC were discussed. Relatively few research results on the microstructure of AASC are available, and the relevant conclusions are not completely consistent. Moreover, there are many constraints on the development of AASC (e.g., complex composition of raw materials of slag, large shrinkage deformation, and low fluidity). Therefore, further research is required.

Degradation Characteristics and Community Structure of a Hydrocarbon Degrading Bacterial Consortium

A hydrocarbon degrading bacterial consortium KO5-2 was isolated from oil-contaminated soil of Karamay in Xinjiang, China, which could remove 56.9% of 10 g/L total petroleum hydrocarbons(TPH) at 30 ℃ after 7 days of incubation, and could also remove 100% of fluorene, 98.93% of phenanthrene and 65.73% of pyrene within 3, 7 and 9 days, respectively. Twelve strains from six different genera were isolated from KO5-2 and only eight ones were able to utilize the TPH. The denaturing gradient gel electrophoresis(DGGE) was used to investigate the microbial community shifts in five different carbon sources(including TPH, saturated hydrocarbons, fluorene, phenanthrene and pyrene). The test results indicated that the community compositions of KO5-2 in carbon sources of TPH and saturated hydrocarbons, respectively, were roughly the same, while they were distinctive in the three different carbon sources of PAHs. Rhodococcus sp. and Pseudomonas sp. could survive in the five kinds of carbon sources. Bacillus sp., Sphingomonas sp. and Ochrobactrum sp. likely played key roles in the degradation of saturated hydrocarbons, PAHs and phenanthrene, respectively. This study showed that specific bacterial phylotypes were associated with different contaminants and complex interactions between bacterial species, and the medium conditions influenced the biodegradation capacity of the microbial communities involved in bioremediation processes.

Mechanical characteristics of soil-rock mixtures containing macropore structure based on 3D modeling technology

Soil-rock mixtures containing macropore(SRMCM)is a kind of geological material with special mechanical properties.Located in the project area of Lenggu hydropower station on the Yalong River,Sichuan Province,China,there is an extremely unstable Mahe talus slide with a total volume of nearly160 million cubic meters,which is mainly composed of SRMCM.The study on the mechanical properties of SRMCM is of great significance for the engineering construction and safe operation.In this paper,laboratory tests and discrete element numerical tests based on three-dimensional scanning technology were conducted to study the influence of stone content,stone size,and the angle of the macropore structure on shear characteristics of SRMCM.The failure mechanism of SRMCM was discussed from a microscopic perspective.This work explains the internal mechanism of the influence of stone content,stone size,and the angle of the macropore structure on the strength of SRMCM through the microscopic level of stone rotation,force chain distribution,and crack propagation.As the macropore structure that intersects with the preset shear plane at a large angle could act as a skeleton-like support to resist the shear force,the fracture of the weak cemented surface of soil and stone in the macropore structure is an important cause of SRMCM destruction.

Effect of Al content on the phase structure and the hydrogenation characteristic of La(Mg_(1-x)Al_x) alloys

La（Mg1-xAlx） （x=0.2, 0.4, 0.6, 0.8） alloys have been prepared using induction melting followed by annealing. It is found that partial substitution of Mg by Al does not lead to a change in crystal structure, and the alloys have a single LaMg phase when x 〈 0.4. The lattice parameter of the LaMg phase decreases obviously after the partial substitution of Mg by Al. However, further substitution of Mg by Al leads to the coexistence of multiple phases when x ≥ 0.6. The alloys consist of the LaMg, LaAl, LaAl2, and La5Al4 phases. The LaMg phase decreases, whereas the La5Al4 phase increases with the increase in x. The Al-substituted La（Mgo.6Al0.4） alloy can be hydrogenated into the tetragonal LaH3, cubic LaH3, MgH2, and LaPd under 5 MPa at 473 K for 5 d.

Analysis of Reflection Characteristics for Foam Filled Grid Structure

The reflection characteristics of gird structures are calculated by the spatial network method in the case of normal incidence plane electromagnetic wave. The numerical result shows that the grid panels without electromagnetic wave absorbing foams are not ideal. However, the absorbing ability can be achieved as low as -25 dBsm from 8 GHz to 12 GHz when the grid cells are filled with foam absorbers. Also it is noted from computation that the foam filled grid structures with larger cell size, higher and thinner ribs will improve the absorbing abilities, which illustrates that they can be used as the effective light-weight stealth structures for aeronautical application.

Prototype test study on mechanical characteristics of segmental lining structure of underwater railway shield tunnel

Based on the first unde rwater railway shield tunnel, the Shiziyang shield tunnel of Guangzhou Zhu- jiang River, the prototype test was carried out against its segmental lining structure by using ＂multi-function shield tunnel structure test system＂. And the mechanical characteristics of segmental lining structure using straight assembling and staggered assembling were studied deeply. The results showed that, the mechanical characteristics of segmental lining structure varied with the water pressures; especially after cracking, the high water pressure played a significant role in slowing down the growing inner force and deformation. It also testi- fied that the failure characteristics varied with straight assembling structure and staggered assembling structure. Shear thilurc often occurred near longitudinal seam when using straight assembling.

Growth,structure and spectral characteristics of KEr_(0.1)Yb_(0.9)(WO_4)_2 laser crystal

The 10 at.% Er3+-doped KYb(WO4)2(KEr0.1Yb0.9(WO4)2) laser crystal with dimensions up to 25 mm×15 mm×10 mm was grown by the Kyropoulos method.The crystal structure was identified as β-KEr0.1Yb0.9(WO4)2 by XRD analysis.Through TG-DTA curves,the melting point and transition point of the crystal were determined to be 1058 and 1031 °C,respectively.Infrared spectrum and Raman spectrum were measured,and the vibration frequencies of infrared and Raman active modes for the crystal were assigned.The absorption cross ...

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.