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Mitigating Lattice Distortion of High‑Voltage LiCoO_(2)via Core‑Shell Structure Induced by Cationic Heterogeneous Co‑Doping for Lithium‑Ion Batteries
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作者 Zezhou Lin Ke Fan +9 位作者 Tiancheng Liu Zhihang Xu Gao Chen Honglei Zhang Hao Li Xuyun Guo Xi Zhang Ye Zhu Peiyu Hou Haitao Huang 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期169-182,共14页
Inactive elemental doping is commonly used to improve the structural stability of high-voltage layered transition-metal oxide cathodes.However,the one-step co-doping strategy usually results in small grain size since ... Inactive elemental doping is commonly used to improve the structural stability of high-voltage layered transition-metal oxide cathodes.However,the one-step co-doping strategy usually results in small grain size since the low diffusivity ions such as Ti^(4+)will be concentrated on grain boundaries,which hinders the grain growth.In order to synthesize large single-crystal layered oxide cathodes,considering the different diffusivities of different dopant ions,we propose a simple two-step multi-element co-doping strategy to fabricate core–shell structured LiCoO_(2)(CS-LCO).In the current work,the high-diffusivity Al^(3+)/Mg^(2+)ions occupy the core of single-crystal grain while the low diffusivity Ti^(4+)ions enrich the shell layer.The Ti^(4+)-enriched shell layer(~12 nm)with Co/Ti substitution and stronger Ti–O bond gives rise to less oxygen ligand holes.In-situ XRD demonstrates the constrained contraction of c-axis lattice parameter and mitigated structural distortion.Under a high upper cut-off voltage of 4.6 V,the single-crystal CS-LCO maintains a reversible capacity of 159.8 mAh g^(−1)with a good retention of~89%after 300 cycles,and reaches a high specific capacity of 163.8 mAh g^(−1)at 5C.The proposed strategy can be extended to other pairs of low-(Zr^(4+),Ta^(5+),and W6+,etc.)and high-diffusivity cations(Zn^(2+),Ni^(2+),and Fe^(3+),etc.)for rational design of advanced layered oxide core–shell structured cathodes for lithium-ion batteries. 展开更多
关键词 Lithium-ion battery LiCoO_(2) heterogeneous co-doping Core-shell structure High-voltage stability
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Research progress of heterogeneous structure magnesium alloys:A review
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作者 Xiang Chen Junlei Zhang +7 位作者 Min Wang Weizhang Wang Di Zhao Haiming Huang Qi Zhao Xiaofei Xu Hongxia Zhang Guangsheng Huang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第6期2147-2181,共35页
In recent years,a new class of metallic materials featuring heterogeneous structures has emerged.These materials consist of distinct soft and hard domains with significant differences in mechanical properties,allowing... In recent years,a new class of metallic materials featuring heterogeneous structures has emerged.These materials consist of distinct soft and hard domains with significant differences in mechanical properties,allowing them to maintain high strength while offering superior ductility.Magnesium(Mg)alloys,renowned for their low density,high specific strength,exceptional vibration damping,and electromagnetic shielding properties,exhibit tremendous potential as lightweight and functional materials.Despite their advantageous properties,high-strength Mg alloys often suffer from limited ductility.However,the emergence of heterogeneous materials provides a fresh perspective for the development of Mg alloys with both high strength and ductility.This article provided a fundamental overview of heterostructured materials and systematically reviewed the recent research progress in the design of Mg alloys with strength-ductility balance based on heterostructure principles.The review encompassed various aspects,including preparation methods,formation mechanisms of diverse heterostructures,and mechanical properties,both within domestic and international contexts.On this basis,the article discussed the challenges encountered in the design and fabrication of heterostructured Mg alloys,as well as the urgent issues that require attention and resolution in the future. 展开更多
关键词 Mg alloys heterogeneous structure Processing techniques Strength and ductility Hetero-deformation induced stress Strain gradient
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Optimal Insurance with Background Risk under the Ambiguity and Belief Heterogeneity Structure
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作者 Xiaohan Wang 《Journal of Applied Mathematics and Physics》 2024年第6期2160-2171,共12页
In this paper, we discuss the optimal insurance in the presence of background risk while the insured is ambiguity averse and there exists belief heterogeneity between the insured and the insurer. We give the optimal i... In this paper, we discuss the optimal insurance in the presence of background risk while the insured is ambiguity averse and there exists belief heterogeneity between the insured and the insurer. We give the optimal insurance contract when maxing the insured’s expected utility of his/her remaining wealth under the smooth ambiguity model and the heterogeneous belief form satisfying the MHR condition. We calculate the insurance premium by using generalized Wang’s premium and also introduce a series of stochastic orders proposed by [1] to describe the relationships among the insurable risk, background risk and ambiguity parameter. We obtain the deductible insurance is the optimal insurance while they meet specific dependence structures. 展开更多
关键词 Optimal Insurance Monotone Hazard Ratio Order Smooth Ambiguity Model Background Risk Belief heterogeneity structure
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Yielding and fracture behaviors of coarse-grain/ultrafine-grain heterogeneous-structured copper with transitional interface 被引量:7
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作者 Yan-fei WANG Ming-sai WANG +3 位作者 Kun YIN Ai-hui HUANG Yu-sheng LI Chong-xiang HUANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第3期588-594,共7页
Heterogeneous-structured Cu samples composed of coarse-grained(CG) and ultrafine-grained(UFG) domains with a transitional interface were fabricated by friction stir processing, in order to investigate the effect of in... Heterogeneous-structured Cu samples composed of coarse-grained(CG) and ultrafine-grained(UFG) domains with a transitional interface were fabricated by friction stir processing, in order to investigate the effect of interface constraint on the yielding and fracture behaviors. Tensile test revealed that the synergetic strengthening induced by elastic/plastic interaction between incompatible domains increases with increasing the area of constraint interface. The strain distribution near interface and the fracture morphology were characterized using digital image correlation technique and scanning electron microscopy, respectively. Fracture dimples preferentially formed at the interface, possibly due to extremely high triaxial stress and strain accumulation near the interface. Surprisingly, the CG domain was fractured by pure shear instead of the expected voids growth caused by tensile stress. 展开更多
关键词 heterogeneous structure INTERFACE constraint synergetic strengthening fracture
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Simultaneous multi-material embedded printing for 3D heterogeneous structures 被引量:4
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作者 Ziqi Gao Jun Yin +4 位作者 Peng Liu Qi Li Runan Zhang Huayong Yang Hongzhao Zhou 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2023年第3期485-498,共14页
In order to mimic the natural heterogeneity of native tissue and provide a better microenvironment for cell culturing,multi-material bioprinting has become a common solution to construct tissue models in vitro.With th... In order to mimic the natural heterogeneity of native tissue and provide a better microenvironment for cell culturing,multi-material bioprinting has become a common solution to construct tissue models in vitro.With the embedded printing method,complex 3D structure can be printed using soft biomaterials with reasonable shape fidelity.However,the current sequential multi-material embedded printing method faces a major challenge,which is the inevitable trade-off between the printed structural integrity and printing precision.Here,we propose a simultaneous multi-material embedded printing method.With this method,we can easily print firmly attached and high-precision multilayer structures.With multiple individually controlled nozzles,different biomaterials can be precisely deposited into a single crevasse,minimizing uncontrolled squeezing and guarantees no contamination of embedding medium within the structure.We analyse the dynamics of the extruded bioink in the embedding medium both analytically and experimentally,and quantitatively evaluate the effects of printing parameters including printing speed and rheology of embedding medium,on the 3D morphology of the printed filament.We demonstrate the printing of double-layer thin-walled structures,each layer less than 200μm,as well as intestine and liver models with 5%gelatin methacryloyl that are crosslinked and extracted from the embedding medium without significant impairment or delamination.The peeling test further proves that the proposed method offers better structural integrity than conventional sequential printing methods.The proposed simultaneous multi-material embedded printing method can serve as a powerful tool to support the complex heterogeneous structure fabrication and open unique prospects for personalized medicine. 展开更多
关键词 embedded printing multi-material printing PRINTABILITY soft materials heterogeneous structures
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Revisiting anisotropy in the tensile and fracture behavior of cold-rolled316L stainless steel with heterogeneous nano-lamellar structures 被引量:2
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作者 Zesheng You Huangliu Fu +2 位作者 Shoudao Qu Weikang Bao Lei Lu 《Nano Materials Science》 CAS 2020年第1期72-79,共8页
We produced a 316 L stainless steel with heterogeneous nanometer-thick lamellar structures by severe cold-rolling at room temperature,and conducted micro-scale tensile tests in different orientations to evaluate both ... We produced a 316 L stainless steel with heterogeneous nanometer-thick lamellar structures by severe cold-rolling at room temperature,and conducted micro-scale tensile tests in different orientations to evaluate both the inplane(parallel to the nano-lamellae)and out-of-plane(normal and 45inclined to the nano-lamellae)mechanical anisotropy.The parallel orientation demonstrates the greatest tensile strength while the inclined orientation exhibits the least strength.The tensile tests in normal and inclined directions also indicate significant transient elastic-plastic response due to the strain path change.Fractographic examination demonstrates that the specimen fails in the normal direction by premature micro-void nucleation and growth,which restricts its tensile strength;however,we identified zig-zag cracking associated with lamellar shear cracking in the inclined direction. 展开更多
关键词 heterogeneous NANO-LAMELLAR structure Mechanical ANISOTROPY Fracture behavior SPECIMEN size EFFECT Strain path EFFECT
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Effects of extrusion temperature on microstructure evolution and mechanical properties of heterogeneous Mg−Gd alloy laminates via accumulated extrusion bonding 被引量:1
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作者 Shuai-shuai LIU Han LIU +5 位作者 Bao-xuan ZHANG Guang-sheng HUANG Xiang CHEN Ai-tao TANG Bin JIANG Fu-sheng PAN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第7期2190-2204,共15页
The influence of extrusion temperature on microstructure and mechanical properties of heterogeneous Mg−1Gd/Mg−13Gd laminate prepared by accumulated extrusion bonding was investigated.The results reveal that the Mg−1Gd... The influence of extrusion temperature on microstructure and mechanical properties of heterogeneous Mg−1Gd/Mg−13Gd laminate prepared by accumulated extrusion bonding was investigated.The results reveal that the Mg−1Gd/Mg−13Gd laminate forms a significant difference in grain size between the successive layers when extruded at 330℃,and this difference gradually disappears as the extrusion temperature increases from 380 to 430℃.Besides,the growth rate of recrystallized grains in fine-grained layers is faster than that in coarse-grained layers.Moreover,the diffusion ability of Gd element increases with elevating extrusion temperatures,promoting the increase and coarsening of precipitates in fine-grained layers.Tensile tests indicate that the sample extruded at 380℃ has a superior combination of strength and ductility.This is mainly attributed to the synergy of the heterogeneous texture between coarse and fine-grained layers,hetero-deformation induced strengthening and hardening.The fine-grained layers facilitate the activation of prismaticáañslips,while coarse-grained layers make it easier to active basaláañand pyramidalác+añslips,especially for the sample extruded at 380℃.The activation of pyramidalác+añslips contributes to coordinating further plastic deformation. 展开更多
关键词 Mg−Gd alloys heterogeneous structure TEXTURE mechanical properties slip modes
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The heterodimeric structure of heterogeneous nuclear ribonucleoprotein C1/C2 dictates 1,25-dihydroxyvitamin D-directed transcriptional events in osteoblasts 被引量:2
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作者 Thomas S Lisse Kanagasabai Vadivel +4 位作者 S Paul Bajaj Rui Zhou Rene F Chun Martin Hewison John S Adams 《Bone Research》 SCIE CAS 2014年第2期110-120,共11页
Heterogeneous nuclear ribonucleoprotein (hnRNP) C plays a key role in RNA processing but also exerts a dominant negative effect on responses to 1,25-dihydroxyvitamin D (1,25(OH)2D) by functioning as a vitamin D ... Heterogeneous nuclear ribonucleoprotein (hnRNP) C plays a key role in RNA processing but also exerts a dominant negative effect on responses to 1,25-dihydroxyvitamin D (1,25(OH)2D) by functioning as a vitamin D response element-binding protein (VDRE-BP). hnRNPC acts a tetramer of hnRNPC1 (huC1) and hnRNPC2 (huC2), and organization of these subunits is critical to in vivo nucleic acid-binding. Overexpression of either huC1 or huC2 in human osteoblasts is sufficient to confer VDRE-BP suppression of 1,25(OH)2D-mediated transcription. However, huC1 or huC2 alone did not suppress 1,25(OH)2D-induced transcription in mouse osteoblastic cells. By contrast, overexpression of huC1 and huC2 in combination or transfection with a bone-specific polycistronic vector using a "self-cleaving" 2A peptide to co-express huC1/C2 suppressed 1,25D-mediated induction of osteoblast target gene expression. Structural diversity of hnRNPC between human/NWPs and mouse/rat/rabbit/dog was investigated by analysis of sequence variations within the hnRNP CLZ domain. The predicted loss of distal helical function in hnRNPC from lower species provides an explanation for the altered interaction between huC1/C2 and their mouse counterparts. These data provide new evidence of a role for hnRNPC1/C2 in 1,25(OH)2D-driven gene expression, and further suggest that species-specific tetramerization is a crucial determinant of its actions as a regulator of VDR-directed transactivation. 展开更多
关键词 gene The heterodimeric structure of heterogeneous nuclear ribonucleoprotein C1/C2 dictates 1 25-dihydroxyvitamin D-directed transcriptional events in osteoblasts Figure EcoRI
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NONLINEAR BUCKLING CHARACTERISTIC OF GRADED MULTIWEB STRUCTURE OF HETEROGENEOUS MATERIALS
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作者 李永 张志民 HUANG Xiao-qing 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第11期1442-1448,共7页
The graded multiweb structure of heterogeneous anisotropic materials, which makes full use of the continuous, gradual and changing physical mechanical performance of material properties, has a widespread application i... The graded multiweb structure of heterogeneous anisotropic materials, which makes full use of the continuous, gradual and changing physical mechanical performance of material properties, has a widespread application in aeroplane aerofoil structure and automobile lightweight structure. On the basis of laminate buckling theory, the equivalent rigidity method is adopted to establish the corresponding constitutive relation and the non-linear buckling governing equation for the graded multiweb structure. In finding the solution, the critical load of buckling under different complicated boundary conditions together with combined loads were obtained and testification of the experimental analysis shows that the calculation results can satisfy the requirements of engineering design in a satisfactory way. Results obtained from the research say that: graded materials can reduce the concentrated stress on the interface in an effective way and weaken the effect of initial defect in materials and thereby improve the strength and toughness of materials. 展开更多
关键词 graded materials multiweb structure BUCKLING heterogeneous
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Structure Sorting of Multiple Macromolecular States in Heterogeneous Cryo-EM Samples by 3D Multivariate Statistical Analysis
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作者 Bruno P. Klaholz 《Open Journal of Statistics》 2015年第7期820-836,共17页
Heterogeneity of biological samples is usually considered a major obstacle for three-dimensional (3D) structure determination of macromolecular complexes. Heterogeneity may occur at the level of composition or conform... Heterogeneity of biological samples is usually considered a major obstacle for three-dimensional (3D) structure determination of macromolecular complexes. Heterogeneity may occur at the level of composition or conformational variability of complexes and affects most 3D structure determination methods that rely on signal averaging. Here, an approach is described that allows sorting structural states based on a 3D statistical approach, the 3D sampling and classification (3D-SC) of 3D structures derived from single particles imaged by cryo electron microscopy (cryo-EM). The method is based on jackknifing & bootstrapping of 3D sub-ensembles and 3D multivariate statistical analysis followed by 3D classification. The robustness of the statistical sorting procedure is corroborated using model data from an RNA polymerase structure and experimental data from a ribosome complex. It allows resolving multiple states within heterogeneous complexes that thus become amendable for a structural analysis despite of their highly flexible nature. The method has important implications for high-resolution structural studies and allows describing structure ensembles to provide insights into the dynamics of multi-component macromolecular assemblies. 展开更多
关键词 heterogeneity structural Biology Cryo Electron Microscopy Particle SORTING MULTIPLE States Macromolecular Complexes RESAMPLING Jackknifing BOOTSTRAPPING Multivariate Statistical Analysis 3D MSA 3D-SC RIBOSOME RNA Polymerase
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Pore Structure Heterogeneity of the Xiamaling Formation Shale Gas Reservoir in the Yanshan Area of China: Evaluation of Geological Controlling Factors 被引量:6
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作者 LI Xueyuan CHEN Shangbin +3 位作者 WANG Xiaoqi ZHU Yanming CHANG Minghua Clementine UWAMAHORO 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第3期588-603,共16页
Micro-heterogeneity is an integral parameter of the pore structure of shale gas reservoir and it forms an essential basis for setting and adjusting development parameters.In this study,scanning electron microscopy,hig... Micro-heterogeneity is an integral parameter of the pore structure of shale gas reservoir and it forms an essential basis for setting and adjusting development parameters.In this study,scanning electron microscopy,high-pressure mercury intrusion and low-temperature nitrogen adsorption experiments were used to qualitatively and quantitatively characterize the pore structure of black shale from the third member of the Xiamaling Formation in the Yanshan area.The pore heterogeneity was studied using fractal theory,and the controlling factors of pore development and heterogeneity were evaluated in combination with geochemical parameters,mineral composition,and geological evolution history.The results show that the pore structure of the reservoir was intricate and complicated.Moreover,various types of micro-nano scale pores such as dissolution pores,intergranular pores,interlayer pores,and micro-cracks are well developed in member 3 of the Xiamaling Formation.The average porosity was found to be 6.30%,and the mean value of the average pore size was 4.78 nm.Micropores and transition pores provided most of the storage space.Pore development was significantly affected by the region and was mainly related to the total organic carbon content,vitrinite reflectance and mineral composition.The fractal dimension,which characterizes the heterogeneity,is 2.66 on average,indicating that the pore structure is highly heterogeneous.Fractal dimension is positively correlated with maturity and clay mineral content,while it is negatively correlated with brittle mineral content and average pore size.These results indicate that pore heterogeneity is closely related to thermal history and material composition.Combined with the geological background of this area,it was found that the pore heterogeneity was mainly controlled by the Jurassic magmatism.The more intense the magma intrusion,the stronger the pore heterogeneity.The pore structure and its heterogeneity characteristics present today are a general reflection of the superimposed geological processes of sedimentary-diagenetic-late transformation.The influence of magmatic intrusion on the reservoir is the main geological factor that should be considered for detailed evaluation of the Xiamaling Formation shale gas reservoir in the Yanshan area. 展开更多
关键词 SHALE gas PORE structure heterogenEITY MAGMA INTRUSION Xiamaling Formation(Fm.) Yanshan area of China
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Pore structure and heterogeneity of shale gas reservoirs and its effect on gas storage capacity in the Qiongzhusi Formation 被引量:8
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作者 Shangbin Chen Zhuo Gong +3 位作者 Xueyuan Li Huijun Wang Yang Wang Yingkun Zhang 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第6期192-208,共17页
Fine characterization of pore systems and heterogeneity of shale reservoirs are significant contents of shale gas reservoir physical property research. The research on micro-control factors of low productivity in the ... Fine characterization of pore systems and heterogeneity of shale reservoirs are significant contents of shale gas reservoir physical property research. The research on micro-control factors of low productivity in the Qiongzhusi Formation(Fm.) is still controversial. The lower Cambrian Qiongzhusi Fm. in the Qujing, Yunnan was taken as the object to investigate the influence of mineral compositions on the physical properties of the reservoir and the heterogeneity of shale, using the algorithm to improve the characterization ability of Atomic Force Microscopy(AFM). The results showed that:(1) The pores are mainly wedge-shaped pores and V-shaped pores. The pore diameter of the main pore segment ranges from 5 to 10 nm. Mesopores are mainly developed in the Qiongzhusi Fm. shale in Well QD1, with the average pore diameter of 6.08 nm.(2) Microscopic pore structure and shale surface properties show strong heterogeneity, which complicates the micro-migration of shale gas and increases the difficulty of identifying high-quality reservoirs.(3) The increase of clay mineral content intensifies the compaction and then destroys the pores. Conversely, brittle minerals can protect pores. The support and protection of brittle minerals to pores space depend on their content, mechanical properties and diagenesis.(4)Compression damage to pores, large microscopic roughness and surface fluctuations and strong pore structure heterogeneity are the reasons for the poor gas storage capacity of the Qiongzhusi Fm., which will lead to poor productivity in the Qiongzhusi Fm. 展开更多
关键词 Shale gas Pore structure heterogenEITY AFM Qiongzhusi Formation
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Factor input structure,environmental policies,and the export quality upgrade:a perspective of heterogeneity 被引量:3
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作者 Jiayue Liu Jing Xie 《Chinese Journal of Population,Resources and Environment》 2018年第1期67-76,共10页
In the analysis of how environmental regulation affects the comparative advantage of trade,existing literature ignores industry's inherent heterogeneity, which draws remarkably different conclusions. In view of th... In the analysis of how environmental regulation affects the comparative advantage of trade,existing literature ignores industry's inherent heterogeneity, which draws remarkably different conclusions. In view of this, the paper analyzed the mechanism of environmental regulation on the export quality of different industries from the perspective of factor input structure heterogeneity. Based on the panel data of China's manufacturing industry, the paper used the system generalized method of moments method to examine the heterogeneity influence of environmental regulation on manufacturing export quality. The study found that, first, environmental regulation affected the export quality upgrade of the manufacturing sector through offset effect and compensation effect, and the direction of the impact would mainly depend on the industry's factor input structure. Second, for industries with larger fixed-asset investment(FAI) ratio in the factor input structure, the current environmental regulation policy was not conducive to the export quality upgrading of the industries. However, there was a significant U-shaped dynamic relationship between them. As environmental regulations became stricter, when regulatory stringency went beyond the inflection point, the policy would promote the upgrading of export quality. But for industries with smaller proportion of FAI, environmental regulation exerted a favorable impact on the export quality upgrade, following a J-shaped marginal growth curve.Third, for industries with different factor input structure, their export quality had been effectively upgraded as expected by factors like human capital investment, independent R&D, technology introduction, and foreign direct investment; but raising per capita capital stock and expanding enterprise size did not produce significant direct impact on export quality upgrade. These conclusions remained robust after using different measurement methods and replacing with other variables. Therefore, this paper suggests that governments should take industry heterogeneity into consideration and formulate differentiated hierarchical environmental policies.Besides, they should strengthen the enforcement of the current environmental regulation policies. By doing so, enterprises are forced to improve their technology and product quality so that they can better cope with rising compliance costs, eliminate backward industries, and resolve excess capacity. In this way, the economic structure would be transformed and upgraded from the supply side. 展开更多
关键词 Environmental regulation export quality factor input structure industry heterogeneity
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Effects of microscopic pore structure heterogeneity on the distribution and morphology of remaining oil 被引量:5
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作者 LI Junjian LIU Yang +3 位作者 GAO Yajun CHENG Baoyang MENG Fanle XU Huaimin 《Petroleum Exploration and Development》 2018年第6期1112-1122,共11页
Waterflooding experiments were performed using Micro-CT on four cores of different pore structures from Donghe sandstone reservoirs in the Tarim Basin. The water, oil and grains were accurately separated by the advanc... Waterflooding experiments were performed using Micro-CT on four cores of different pore structures from Donghe sandstone reservoirs in the Tarim Basin. The water, oil and grains were accurately separated by the advanced image processing technology, the pore network model was established, and parameters such as the number of throats and the throat size distribution were calculated to characterize the microscopic heterogeneity of pore structure, the flow of oil phase during displacement, and the morphology and distribution of remaining oil after displacement. The cores with the same macroscopic porosity-permeability have great differences in microscopic heterogeneity of pore structure. Both macro porosity-permeability and micro heterogeneity of pore structure have an influence on the migration of oil phase and the morphology and distribution of remaining oil. When the heterogeneity is strong, the water phase will preferentially flow through the dominant paths and the remaining oil clusters will be formed in the small pores. The more the number of oil clusters(droplets) formed during displacement process, the smaller the average volume of cluster is, and the remaining oil is dominated by the cluster continuous phase with high saturation. The weaker the heterogeneity, the higher the pore sweep efficiency is, and the remaining oil clusters are mainly trapped in the form of non-continuous phase. The distribution and morphology of micro remaining oil are related to the absolute permeability, capillary number and micro-heterogeneity. So, the identification plate of microscopic residual oil continuity distribution established on this basis can describe the relationship between these three factors and distribution of remaining oil and identify the continuity of the remaining oil distribution accurately. 展开更多
关键词 SANDSTONE WATERFLOODING CT scan image processing MICROSCOPIC pore structure reservoir heterogenEITY REMAINING oil DISTRIBUTION
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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
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作者 Lei Wang Xiao Lei +7 位作者 Qiao-Liang Zhang Guang-Qing Yao Bo Sui Xiao-Jun Chen Ming-Wei Wang Zhen-Yu Zhou Pan-Rong Wang Xiao-Dong Peng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1044-1061,共18页
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... 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. 展开更多
关键词 Beibuwan Basin Multistage pore-throat structure Multistage seepage characteristics Microscopic visualization heterogenEITY Gas/water flooding Flooding mode
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Heterogeneity and Secondary Structure Analysis of 3' Untranslated Region in Classical Swine Fever Viruses 被引量:1
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作者 FAN Yun-feng ZHAO Qi-zu +4 位作者 ZHAO Yun ZOU Xing-qi ZHANG Zhong-qiu WANG Qin NING Yi-bao 《Agricultural Sciences in China》 CAS CSCD 2011年第1期142-148,共7页
The attenuated vaccine strains of CSFV have a 12-nucleotides (nt) insertion in the 3'-UTR of genome as compared to that of CSFV virulent strains. In this study, we found a distinct heterogeneity in the 3'-UTR of a... The attenuated vaccine strains of CSFV have a 12-nucleotides (nt) insertion in the 3'-UTR of genome as compared to that of CSFV virulent strains. In this study, we found a distinct heterogeneity in the 3'-UTR of attenuated Thiverval and HCLV strains. The longest 3'-UTR of Thiverval strain was 259 base pairs (bp) with a 32-nt insertion, the shortest 3'-UTR had only 233 bp with a 6-nt insertion. The longest 3'-UTR of HCLV strain was 244 bp with a 17-nt insertion and the shortest 3' UTR was 235 bp with a 8-nt insertion. Compared with the published sequences of 3'-UTR of vaccine and virulent strains, the 3'-UTR of CSFV vaccine strains have two variable regions where insertion among the different vaccine strains were frequently found. The first is located between the second conservative TALk codon and the start of T-rich region where we found the variable length insertion in the same vaccine strain Thiveral or HCLV and the second is located between the end of T-rich region and the front of GAA eodon, however, a 4-nt deletion was found in this region in the virulent Shimen strain. These two regions may represent the "hot spot" for mutation. Modeling the secondary structures of the 3'-UTR suggests that the T-rich insertion could result in the change of structure and free energy, thus affecting the stability of the 3'-UTR structure. These findings will help to understand the mechanism of attenuated vaccines and improve vaccine safety, stability, and efficacy. 展开更多
关键词 classical swine fever virus 3'-UTR heterogenEITY RNA secondary structure
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Improving the ductility and toughness of nano-TiC/AZ61 composite by optimizing bimodal grain microstructure via extrusion speed
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作者 Lingling Fan Mingyang Zhou +5 位作者 Wulve Lao Yuwenxi Zhang Hajo Dieringa Ying Zeng Yuanding Huang Gaofeng Quan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第8期3264-3280,共17页
In this study,the nano-TiC/AZ61 composites with different heterogeneous bimodal grain(HBG)structures and uniform structure are obtained by regulating the extrusion speed.The effect of HBG structure on the mechanical p... In this study,the nano-TiC/AZ61 composites with different heterogeneous bimodal grain(HBG)structures and uniform structure are obtained by regulating the extrusion speed.The effect of HBG structure on the mechanical properties of the composites is investigated.The increasing ductility and toughening mechanism of HBG magnesium matrix composites are carefully discussed.When the extrusion speed increases from 0.75 mm/s to 2.5 mm/s or 3.5 mm/s,the microstructure transforms from uniform to HBG structure.Compared with Uniform-0.75 mm/s composite,Heterogeneous-3.5 mm/s composite achieves a 116.7%increase in ductility in the plastic deformation stage and almost no reduction in ultimate tensile strength.This is mainly because the lower plastic deformation inhomogeneity and higher strain hardening due to hetero-deformation induced(HDI)hardening.Moreover,Heterogeneous-3.5 mm/s composite achieves a 108.3%increase in toughness compared with the Uniform-0.75 mm/s composite.It is mainly because coarse grain(CG)bands can capture and blunt cracks,thereby increasing the energy dissipation for crack propagation and improving toughness.In addition,the CG band of the Heterogeneous-3.5 mm/s composite with larger grain size and lower dislocation density is more conducive to obtaining higher strain hardening and superior blunting crack capability.Thus,the increased ductility and toughness of the Heterogeneous-3.5 mm/s composite is more significant than that Heterogeneous-2.5 mm/s composite. 展开更多
关键词 Nano-TiC/AZ61 composite Extrusion speed heterogeneous bimodal grain structure Increasing ductility mechanism Toughening mechanism
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Synchrotron radiation facility-based quantitative evaluation of pore structure heterogeneity and anisotropy in coal 被引量:1
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作者 SUN Yingfeng ZHAO Yixin +2 位作者 WANG Xin PENG Lei SUN Qiang 《Petroleum Exploration and Development》 2019年第6期1195-1205,共11页
In order to quantify coal pore structure heterogeneity and anisotropy,synchrotron radiation SAXS(Small Angle X-ray Scattering)was applied to obtain the SAXS images of two different rank coal samples.The surface fracta... In order to quantify coal pore structure heterogeneity and anisotropy,synchrotron radiation SAXS(Small Angle X-ray Scattering)was applied to obtain the SAXS images of two different rank coal samples.The surface fractal dimension(D1)and pore fractal dimension(D2)were obtained by processing the image data.The pore structure heterogeneity of two coal samples was quantified by pore fractal dimension(D2).Pore fractal dimension of Xinzhouyao coal is 2.74 and pore fractal dimension of Tangshan coal is 1.69.As a result,the pore structure heterogeneity of Xinzhouyao coal is stronger than that of Tangshan coal.3D pore structure imaging was achieved by synchrotron radiation nano-CT.The selected Region of Interest(ROI)of coal sample was divided into a certain number of subvolumes.Pore structure heterogeneity was quantified by calculating the limit of the relative standard deviation of each subvolume’s porosity.The heterogeneity value of Xinzhouyao coal pore structure is 3.21 and the heterogeneity value of Tangshan coal pore structure is 2.71.As a result,the pore structure heterogeneity of Xinzhouyao coal is also stronger than that of Tangshan coal,namely,pore structure heterogeneity from synchrotron radiation SAXS and synchrotron radiation nano-CT is consistent.Considering the corresponding relationship between the pore structure anisotropy and the permeability anisotropy,the quantification of pore structure anisotropy was realized by computing the permeability tensor of pore structure using the Lattice Boltzmann method(LBM),and the pore structure anisotropy was characterized by the eigenvalues and eigenvectors of the permeability tensor.The pore structure anisotropy obtained by the method proposed in this paper was validated by the pore structure geometrical morphology. 展开更多
关键词 SYNCHROTRON RADIATION SAXS SYNCHROTRON RADIATION nano-CT COAL pore structure heterogenEITY ANISOTROPY
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Vertical Heterogeneity of Genotypic Structure and Toxic Potential within Populations of the Harmful Cyanobacterium Microcystis aeruginosa
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作者 Benjamin Misson Delphine Latour 《Advances in Microbiology》 2013年第6期27-37,共11页
We investigated the vertical variability of toxic potential (i.e. proportions of cells containing microcystin genes) and genotypic structure within different populations of Microcystis aeruginosa that developed in dee... We investigated the vertical variability of toxic potential (i.e. proportions of cells containing microcystin genes) and genotypic structure within different populations of Microcystis aeruginosa that developed in deep artificial reservoirs on the Loire River (France). We demonstrated that a great qualitative vertical heterogeneity could exist within a single bloom of this cyanobacterium in deep lakes. Indeed, we observed important vertical shifts of both toxic potential and genotypic structure, whatever the bloom magnitude. These variations occurred mainly within the euphotic zone and proved to occur independently from abundance vertical shifts. One of the most striking results of this study is that the genotypic structure of a population of M. aeruginosa was more variable between different depths sampled at a single site than between different sites of the same reservoir sampled on top of the water column. In the same way the proportion of potentially toxic cells was sometimes more variable vertically than horizontally. The occurrence of such vertical heterogeneity in three different blooms suggests that this could be a frequent pattern within populations of M. aeruginosa. 展开更多
关键词 Cyanobacteria MICROCYSTIS AERUGINOSA Genetic structure Toxic POTENTIAL Vertical heterogeneity
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Dengue virus non-structural 1 protein interacts with heterogeneous nuclear ribonucleoprotein H in human monocytic cells
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作者 Drishya Diwaker Mishra K P +1 位作者 Ganju L Singh S B 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2016年第2期109-114,共6页
Objective: To study protein-protein interaction between heterogeneous nuclear ribonucleoprotein H(hn RNP H) and Dengue virus(DENV) proteins. Methods: DENV proteins were screened against the host hn RNP H protein, in o... Objective: To study protein-protein interaction between heterogeneous nuclear ribonucleoprotein H(hn RNP H) and Dengue virus(DENV) proteins. Methods: DENV proteins were screened against the host hn RNP H protein, in order to identify the host-viral protein-protein interactions in DENV infected THP-1 cells by co-immunoprecipitation. The co-localization of the interacting proteins was further confirmed by immunofluorescence microscopy. Results: The host protein hn RNP H was found to interact with DENV nonstructural 1 protein and help the virus to multiply in the cell. Conclusions: The non-structural 1 glycoprotein is a key modulator of host immune response and is also involved in viral replication. Therefore, disruption of this key interaction between hn RNP H and DENV nonstructural 1 could be an important therapeutic strategy for management of DENV infection. 展开更多
关键词 DENGUE virus NON-structurAL 1 PROTEIN heterogeneous nuclear RIBONUCLEOPROTEIN H PROTEIN interactions
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