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NBT基陶瓷的储能性能调控研究进展

现代化工 2024年第5期44卷 76-81页

作者：张子宣陈超陈刚高荣礼蔡苇符春林重庆科技大学化学化工学院重庆401331 重庆科技大学冶金与材料工程学院重庆401331 纳微复合材料与器件重庆市重点实验室重庆401331

综述了NBT基铁电陶瓷弛豫特性增强途径及结构设计调控储能性能方法。首先介绍了NBT的晶体结构及其相变,其次详细阐述了增强NBT陶瓷弛豫性和储能性能调控方法,最后对NBT基弛豫铁电材料未来的方向和发展提出了见解。

关键词： NBT基陶瓷弛豫储能无铅复合材料

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Symmetrical Independence Tests for Two Random Vectors with Arbitrary Dimensional Graphs

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Acta Mathematica Sinica,English Series 2022年第4期38卷 662-682页

作者： Jia Min liU gao rong li Jian Qiang ZHANG Wang li XU Center for Applied Statistics Renmin University of ChinaBeijing 100872P.R.China School of Statistics Beijing Normal UniversityBeijing 100875P.R.China

Test of independence between random vectors X and Y is an essential task in statistical *** type of testing methods is based on the minimal spanning tree of variables X and *** main idea is to generate the minimal spanning tree for one random vector X,and for each edges in minimal spanning tree,the corresponding rank number can be calculated based on another random vector *** resulting test statistics are constructed by these rank ***,the existed statistics are not symmetrical tests about the random vectors X and Y such that the power performance from minimal spanning tree of X is not the same as that from minimal spanning tree of *** addition,the conclusion from minimal spanning tree of X might conflict with that from minimal spanning tree of *** order to solve these problems,we propose several symmetrical independence tests for X and *** exact distributions of test statistics are investigated when the sample size is ***,we study the asymptotic properties of the statistics.A permutation method is introduced for getting critical values of the *** with the existing methods,our proposed methods are more efficient demonstrated by numerical analysis.

关键词： Exact distribution minimal spanning tree asymptotic distribution symmetrical independence test

Synergistic effect of Zr and Mo on precipitation and high-temperature properties of Al-Si-Cu-Mg alloys

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China Foundry 2024年第1期21卷 71-81页

作者： Chao gao Bing-rong Zhang Yin-ming li Zhi-ming Wang Xiang-bin Meng Faculty of Mechanical Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China Hebei Ounai Machinery Mould Co.Ltd. Xingtai 054500HebeiChina

This study focuses on finding a solution to the sharp decline in mechanical properties of Al-Si-Cu-Mg alloys due to rapid coarsening of traditional intermediate phases at high temperature.A new type of modified al oy,to be used in automobile engines at high temperatures,was prepared by adding Zr and Mo into Al-Si-Cu-Mg *** synergistic effects of Zr and Mo on the microstructure evolution and high-temperature mechanical properties were *** show that the addition of Zr and Mo generates a series of intermetallic phases dispersed in the *** can improve the strength of the alloy by hindering dislocation movement and crack *** addition,some nano-strengthened phases show coherent interfaces with the matrix and improve grain *** addition of Mo greatly improves the heat resistance of the *** extremely low diffusivity of Mo enables it to improve the thermal stability of the intermetallic phases,inhibit precipitation during aging,reduce the size of the precipitates,and improve the heat resistance of the alloy.

关键词： Al-Si-Cu-Mg alloy high-temperature properties Zr-Mo-rich intermetallics nano-strengthening phases

Formation mechanism of fault accommodation zones under combined stress in graben basin:Implications from geomechanical modeling

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Petroleum Science 2024年第1期21卷 54-76页

作者： Qi-Qiang Ren Jin-liang gao rong-Tao Jiang Jin Wang Meng-Ping li Jian-Wei Feng Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059SichuanChina PetroChina Research Institute of Petroleum Exploration and Development Beijing100083China Jianghan Oilfield Oil and Gas Production Capacity Construction Management Center Chongqing408000China Sinopec Chongqing Fuling Shale Gas Exploration and Development Company Chongqing408000China College of Energy Chengdu University of TechnologyChengdu 610059SichuanChina School of Geoscience China University of Petroleum(East China)Qingdao 266580ShandongChina

A fault accommodation zone is a type of structure that is defined as regulating displacement and strain between faults *** numbers of fault accommodation zones are being identified in graben basins,indicating the potential exploration target and petroleum accumulation *** study aims to analyze the formation mechanism and development of fault accommodation zones under combined stress by a numerical simulation method considering geomechanical *** three-dimensional(3-D)seismic interpretation and fractal dimension method,exampled with the Dongxin fault zone,the fault activity and fault combination pattern were conducted to quantitatively characterize the activity difference in fault accommodation *** with mechanical experiment test,a geomehcanical model was established for fault accommodation zones in a graben *** the paleostress numerical simulations and structural physical simulation experiment,the developmental characteristics and genetic mechanism of fault accommodation zones were *** by multi movements and combined stresses,three significant tectonic evolution stages of the Dongxing Fault Zone(DXFZ)were distinguished:During the E_(s)^(3)sedimentary period,the large difference in the stress,strain,and rupture distribution in various faults were significant,and this stage was the key generation period for the prototype of the DXFZ,including the FAZ between large-scale *** the E_(s)^(2)sedimentary period,the EW-trending symmetric with opposite dipping normal faults and the NE-SW trending faults with large scale were furtherly *** junction area of two secondary normal faults were prone to be ruptured,performing significant period for inheriting and developing characteristics of fault accommodation *** the Es1 sedimentary period,the high-order faults in the DXFZ exhibited the obvious fault depressions and strike-slip activity,and the fault accommodation zones were

关键词： Fault accommodation zone Graben basin Fault activity Tectonic physical simulation experiment Finite element numerical simulation Dongxin fault zone

Energy saving analysis for CO_(2)–O_(2)mixed injection technology in converter steelmaking

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Journal of Iron and Steel Research(International) 2024年第5期31卷 1095-1103页

作者： Bao-chen Han Chun-liang gao Ya-qiang li Dan liu Guang-sheng Wei rong Zhu Hebei Key Laboratory of Material Near-Net Forming Technology School of Material Science and EngineeringHebei University of Science and TechnologyShijiazhuang050018HebeiChina Department of Automotive Engineering Hebei Vocational University of Technology and EngineeringXingtai054000HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

Energy-saving in China's iron and steel industry still relies on the development and improvement of short-term energy saving ***,a special converter smelting technology incorporating energy saving was *** evaluate the energy-saving potential of the CO_(2)–O_(2)mixed injection(COMI)technology,collected production data were used to develop an improved techno-economic *** reveal that the technology can save energy through auxiliary material consumption,sensible heat of solid by-product,iron loss reduction,and energy *** application of COMI technology in an enterprise is cost effective,involving the energy saving potential of 0.206 GJ/t,the cost of conserved energy of−48.83 yuan/GJ,and a simple payback period of 0.35 year for a 60-million-yuan *** analysis shows that the investment cost and discount rate primarily influence the cost of conserved energy of the *** the discount rate increased,the cost of conserved energy also gradually ***,the COMI technology is an energy-saving technology with good development prospects.

关键词： Converter steelmaking COMI technology Energy saving Techno-economic model Investment cost

Generalized Empirical likelihood Inference in Semiparametric Regression Model for Longitudinal Data

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Acta Mathematica Sinica,English Series 2008年第12期24卷 2029-2040页

作者： gao rong li Ping TIAN liu Gen XUE College of Applied Sciences Beijing University of Technology Beijing 100022 P. R. China School of Finance and Statistics East China Normal University Shanghai 200241 P. R. China Department of Mathematics Xuchang University Xuchang 461000 P. R. China

In this paper, we consider the semiparametric regression model for longitudinal data. Due to the correlation within groups, a generalized empirical log-likelihood ratio statistic for the unknown parameters in the model is suggested by introducing the working covariance matrix. It is proved that the proposed statistic is asymptotically standard chi-squared under some suitable conditions, and hence it can be used to construct the confidence regions of the parameters. A simulation study is conducted to compare the proposed method with the generalized least squares method in terms of coverage accuracy and average lengths of the confidence intervals.

关键词： longitudinal data semiparametric regression model empirical likelihood confidence region

Different El Niño Flavors and Associated Atmospheric Teleconnections as Simulated in a Hybrid Coupled Model

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Advances in Atmospheric Sciences 2024年第5期41卷 864-880页

作者： Junya HU Hongna WANG Chuan gao rong-Hua ZHANG Key Laboratory of Ocean Circulation and Waves Institute of Oceanologyand Center for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China School of Marine Sciences Nanjing University of Information Science and TechnologyNanjing 210044China Laoshan Laboratory Qingdao 266237China

A previously developed hybrid coupled model(HCM)is composed of an intermediate tropical Pacific Ocean model and a global atmospheric general circulation model(AGCM),denoted as *** this study,different El Niño flavors,namely the Eastern-Pacific(EP)and Central-Pacific(CP)types,and the associated global atmospheric teleconnections are examined in a 1000-yr control simulation of the *** HCMAGCM indicates profoundly different characteristics among EP and CP El Niño events in terms of related oceanic and atmospheric variables in the tropical Pacific,including the amplitude and spatial patterns of sea surface temperature(SST),zonal wind stress,and precipitation *** SST budget analysis indicates that the thermocline feedback and zonal advective feedback dominantly contribute to the growth of EP and CP El Niño events,*** to the shifts in the tropical rainfall and deep convection during EP and CP El Niño events,the model also reproduces the differences in the extratropical atmospheric responses during the boreal *** particular,the EP El Niño tends to be dominant in exciting a poleward wave train pattern to the Northern Hemisphere,while the CP El Niño tends to preferably produce a wave train similar to the Pacific North American(PNA)*** a result,different climatic impacts exist in North American regions,with a warm-north and cold-south pattern during an EP El Niño and a warm-northeast and cold-southwest pattern during a CP El Niño,*** modeling result highlights the importance of internal natural processes within the tropical Pacific as they relate to the genesis of ENSO diversity because the active ocean–atmosphere coupling is allowed only in the tropical Pacific within the framework of the HCMAGCM.

关键词： hybrid coupled model tropical Pacific Ocean global atmosphere Eastern/Central-Pacific El Niño atmospheric teleconnections

Impact of volcanism on the formation and hydrocarbon generation of organic-rich shale in the Jiyang Depression, Bohai Bay Basin, China

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Petroleum Science 2024年第3期21卷 1539-1551页

作者： Jia-Hong gao Xin-Ping liang Zhi-Jun Jin Quan-You liu Chang-rong li Xiao-Wei Huang Ju-Ye Shi Peng li State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Efficient Development Institute of Energy Peking University Petroleum Exploration and Production Research Institute SINOPEC School of Energy Resources China University of Geosciences

Globally, most organic-rich shales are deposited with volcanic ash layers. Volcanic ash, a source for many sedimentary basins, can affect the sedimentary water environment, alter the primary productivity, and preserve the organic matter（OM） through physical, chemical, and biological reactions. With an increasing number of breakthroughs in shale oil exploration in the Bohai Bay Basin in recent years, less attention has been paid to the crucial role of volcanic impact especially its influence on the OM enrichment and hydrocarbon formation. Here, we studied the petrology, mineralogy, and geochemical characteristics of the organic-rich shale in the upper submember of the fourth member（Es4～1） and the lower submember of the third member（Es3～3） of the Shahejie Formation, aiming to better understand the volcanic impact on organic-rich shale formation. Our results show that total organic carbon is higher in the upper shale intervals rich in volcanic ash with enriched light rare earth elements and moderate Eu anomalies. This indicates that volcanism promoted OM formation before or after the eruption. The positive correlation between Eu/Eu* and Post-Archean Australian Shale indicates hydrothermal activity before the volcanic eruption. The plane graph of the hydrocarbon-generating intensity（S1+S2） suggests that the heat released by volcanism promoted hydrocarbon generation. Meanwhile, the nutrients carried by volcanic ash promoted biological blooms during Es4～1 and Es3～3 deposition, yielding a high primary productivity. Biological blooms consume large amounts of oxygen and form anoxic environments conducive to the burial and preservation of OM. Therefore, this study helps to further understand the organic-inorganic interactions caused by typical geological events and provides a guide for the next step of shale oil exploration and development in other lacustrine basins in China.

关键词： Volcanic ash Hydrocarbon generation Organic-rich shale Shahejie Formation Jiyang Depression

Segmental nature of the Red River fault revealed by seismic anisotropy and geological structures

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Science China Earth Sciences 2024年第8期67卷 2423-2443页

作者： Ying li Yuan gao School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Key Laboratory of Earthquake Prediction Institute of Earthquake ForecastingChina Earthquake AdministrationBeijing 100036China

As the western boundary of the Sichuan-Yunnan block(SYB),the Red River fault(RRF)is a major fault that controls deep crustal movement and deformation in the southeast margin of the Tibetan Plateau and regulates middle-lower crustal *** data suggest that the RRF is segmented and exhibits distinct variations in seismicity,velocity structure and crustal deformation from north to *** anisotropy reveals a complex pattern of lateral spatial and vertical stratified distributions.(1)From the perspective of crustal stratification,in the upper crust,the fast wave polarization in the north segment of the RRF is complex and possibly influenced by the Sanjiang lateral collision zone and adjacent faults with varying *** fast wave polarization in the middle segment is in the NW-SE direction,indicating a localized area of closed down or locked up with consistent *** in the south segment,it presents a disordered pattern,signifying complex deep tectonics and stress conditions at the wedged intersection *** the middle-lower crust in the north and south segments of the RRF,the azimuthal anisotropy is strong and consistent with the spatial strike of the weak zone characterized by low-velocity and *** suggests a connection between the anisotropy and the material migration.(2)In the whole crustal scale,the fast wave directions in two sides of the RRF are consistent with the NW-SE tectonic *** indicates that the RRF,as a large fault potentially cutting through the whole crust,strongly controls the surrounding media.(3)In the lithospheric scale,the fast wave polarizations are oriented nearly E-W and independent of the fault strike,consistent with the low P-and S-wave velocity structures and positive radial anisotropy in the upper *** fast wave directions could be related to lithospheric olivine deformation and asthenospheric *** paper suggests a decoupling of deformation between the crust and the lithospheri

关键词： Red River fault Seismic anisotropy Geological structures lithosphere Fault segmentation