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Strong electron correlation-induced Mott-insulating electrides of Ae_(5)X_(3)(Ae=Ca,Sr,and Ba;X=As and Sb)

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Matter and Radiation at Extremes 2024年第3期9卷 74-82页

作者： ya Xu Lu Zheng Yunkun zhang Zhuangfei zhang QianQian Wang Yuewen zhang Liangchao Chen chao Fang Biao Wan Huiyang Gou Key Laboratory of Material Physics of Ministry of Education School of Physics and Laboratory of Zhongyuan LightZhengzhou UniversityZhengzhou 450052China School of Mechanical and Equipment Engineering Hebei University of EngineeringHandan 056038China Center for High Pressure Science and Technology Advanced Research Beijing 100094China

The presence of interstitial electrons in electrides endows them with interesting attributes,such as low work function,high carrier concentration,and unique magnetic *** knowledge and understanding of electrides are thus of both scientific and technological ***,we employ first-principles calculations to investigate Mott-insulating Ae_(5)X_(3)(Ae=Ca,Sr,and Ba;X=As and Sb)electrides with Mn_(5)Si_(3)-type structure,in which half-filled interstitial electrons serve as ions and are *** Mott-insulating property is induced by strong electron correlation between the nearest interstitial electrons,resulting in spin splitting and a separation between occupied and unoccupied *** half-filled antiferromagnetic configuration and localization of the interstitial electrons are critical for the Mott-insulating properties of these *** with that in intermetallic electrides,the orbital hybridization between the half-filled interstitial electrons and the surrounding atoms is weak,leading to highly localized magnetic centers and pronounced correlation ***,the Mott-insulating electrides Ae_(5)X_(3)have very large indirect bandgaps(0.30 eV).In addition,high pressure is found to strengthen the strong correlation effects and enlarge the *** present results provide a deeper understanding of the formation mechanism of Mott-insulating electrides and provide guidance for the search for new strongly correlated electrides.

关键词： intermetallic filled occupied

Adverse effect of niobium and boron on hot deformation behavior of sulfur-containing steel

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Journal of Iron and Steel Research International 2024年第1期31卷 252-263页

作者： Guo-ning He Shi-qi Wan Bo Jiang chao-lei zhang ya-zheng Liu Chun-jing Wu School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing100083China

The hot deformation behaviors of sulfur-containing gear steel 20MnCr5 containing three different contents of Nb and B(0,0.021%Nb,and 0.024%Nb-0.0022%B)were *** compression and tenssion tests were carried out by Gleeble3800 at the austenite region from 850 to 1150℃and the adverse effects of Nb and B were analyzed by the fracture,microstructure and precipitate *** compression tests showed that the proportions of instable area in hot processing maps of 0.021%Nb and Nb-B steels were higher and the deformability of Nb free steel was *** tensile deformation experiments showed that the reduction areas of Nb free,0.021%Nb and Nb-B steels were 92%-99%,84%-98%and 67%-97%,*** addition of Nb or Nb and B inhibited the dynamic recrystallization during hot deformation,and consequently,more deformed grains were then formed in 0.021%Nb and Nb-B steels thus to obtain the microstructure with worse uniformity and then deteriorate the *** addition,the interaction between inclusions and microalloyed elements was also *** particles of 0.021%Nb and Nb-B steels dynamically precipitated during deformation and precipitated together with MnS thus to worsen the deformability,resulting in the decrease of reduction area.

关键词： Hot deformation Gear steel Processing map Dynamic recrystallization Microalloying

Simulation method of Wolter type Ⅰ grazing incidence telescope imaging of an X-ray region

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Research in Astronomy and Astrophysics 2019年第12期19卷 179-186页

作者： Peng Liu Bo Chen ya-chao zhang Ling-Ping He Xiao-Dong Wang Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesJilin 130033China University of Chinese Academy of Sciences Beijing 100049China

This paper presents a method for simulating Wolter type Ⅰ grazing incidence telescope imaging of an X-ray region. The imaging quality of a soft X-ray telescope is mainly affected by geometric aberrations,surface scatter and alignment errors. Using a Legendre-Fourier polynomial to fit the figure errors in the cylindrical coordinate system, the geometry of the mirror barrel with the figure errors can be modeled by the User Defined Object in ZEMAX. Based on the Harvey-Shack surface scatter theory, surface scatter is achieved by the Bidirectional Scatter Distribution Function(BSDF) scattering model. The alignment errors are calculated by a combination of experiment and simulation according to the shape of the spot resulting from the finite distance imaging experiment. By combining these factors that affect image quality,the telescope imaging of an infinity point is simulated by ZEMAX. According to the simulation results, the angular resolution of the telescope is calculated to be less than or equal to 1.86′ at a wavelength of 1.33 *** simulation method improves the ability of ZEMAX to simulate grazing incidence telescope *** is of great significance for the research and manufacture of X-ray grazing incidence telescopes.

关键词： telescopes scattering methods:miscellaneous

Dependence of the propagation characteristics of buried channel glass waveguides on the fabrication parameters

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Optoelectronics Letters 2008年第1期4卷 9-11页

作者： zhang ya-li, LIU chao, zhang yan, LI Wei, zhang Bang-hong, and ZHU Ning-hua State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Science, Beijing 10083, China State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Science Beijing China

Based on the variational analysis of the Er+-Yb+ co-doped glass optical waveguide,the dependence of the mode profiles and propagation characteristics on the fabrication parameters, mainly on the channel waveguide width and the annealing time, are investigated. Different influences of these parameters on the mode dimensions, the center position of the depth field profile, the effective refractive index, and overlap factor are shown in this letter, according to which the appropriate prepa- ration conditions can be chosen.

关键词：掩埋信道玻璃波导制作参数传播特征光波导

Association between heat and upper urinary tract stones morbidity and medical costs: A study in the subtropical humid climate zone

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Advances in Climate Change Research 2024年第4期15卷 717-724页

作者： Chen-Lu yaNG Jun-Zhe BAO Peng BI ya-Dong zhang chao-Ming TAN Kai CHEN College of Public Health Zhengzhou UniversityZhengzhou 450001China School of Public Health The University of AdelaideAdelaide 5000Australia Department of Andrology The First Affliated Hospital of Sun Yat-sen UniversityGuangzhou 510080China Nanjing Social Insurance Management Center Nanjing 210008China Department of Environmental Health Sciences Yale UniversityNew Haven 06520USA yale Center on Climate Change and Health Yale UniversityNew Haven 06520USA

Urolithiasis is a heat-specific *** heat-related urolithiasis susceptibility subtypes,economic burden,and modifying factors could assist governments in targeting interventions to reduce the heat-related health risks of urolithiasis *** collected data on 23,492 patients with upper urinary tract stones(main subtypes of urolithiasis)from 2013 to 2017 in Nanjing,*** adopted generalized additive quasi-Poisson models to examine the associations between daily mean temperatures and morbidity of upper urinary tract stones,while generalized additive Gaussian models were used to explore the relationships between temperatures and log-transformed medical *** examined the modification effects of disease subtypes(kidney and ureteral calculus),sex,and age through stratified analyses and the modif-cation effects of other meteorological factors by introducing interaction terms in the *** found that short-term summer heat exposure has a statistically significant effect on ureteral calculus morbidity but not on kidney calculus *** ureter calculus,a 1℃ temperature increase was associated with a 4.36%(95%confidence interval[CI]:1.94%,6.83%)increase in daily hospitalization and a 5.44%(95%CI:2.71%,8.25%)increase in daily medical *** attributable fraction associated with heat(greater than the median value of daily mean temperature,26.8℃)was 7.85%(95%empirical confidence interval[eCI]:3.64%,11.44%)for hospitalization and 9.36%(95%eCI:4.91%,13.14%)for medical *** effects of heat on ureter calculus morbidity were significantly higher among the males and those with high sunshine duration than females and those with low sunshine ***-term summer heat exposure was associated with increased morbidity and medical costs of ureteral *** government organizations should take effective intervention measures,including community health education,to reduce the health hazards and economic losses caused by heat.

关键词： Heat Upper urinary tract stones Economic burden Modification effects

Enhancing the vertical resolution of lunar penetrating radar data using predictive deconvolution

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Earth and Planetary Physics 2024年第4期8卷 570-578页

作者： chao Li JinHai zhang CAS Engineering Laboratory for Deep Resources Equipment and Technology Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

The Yutu-2 rover onboard the Chang’E-4 mission performed the first lunar penetrating radar detection on the farside of the *** high-frequency channel presented us with many unprecedented details of the subsurface structures within a depth of approximately 50 ***,it was still difficult to identify finer layers from the cluttered reflections and scattering *** applied deconvolution to improve the vertical resolution of the radar profile by extending the limited bandwidth associated with the emissive radar *** overcome the challenges arising from the mixed-phase wavelets and the problematic amplification of noise,we performed predictive deconvolution to remove the minimum-phase components from the Chang’E-4 dataset,followed by a comprehensive phase rotation to rectify phase anomalies in the radar ***,we implemented irreversible migration filtering to mitigate the noise and diminutive clutter echoes amplified by *** processed data showed evident enhancement of the vertical resolution with a widened bandwidth in the frequency domain and better signal clarity in the time domain,providing us with more undisputed details of subsurface structures near the Chang’E-4 landing site.

关键词： Chang’E-4 lunar penetrating radar data processing predictive deconvolution irreversible migration filtering

Surface-targeted functionalization of nickel-rich cathodes through synergistic slurry additive approach with multi-level impact using minimal quantity

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Nano Research 2024年第1期17卷 333-343页

作者： Jing zhang Jiapei Li Longhao Cao Wenhua Cheng Ziyin Guo Xiuxia Zuo chao Wang ya-Jun Cheng Yonggao Xia Yudai Huang State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of ChemistryXinjiang UniversityUrumqi 830017China Ningbo Institute of Materials Technology&Engineering Chinese Academy of SciencesNingbo 315201China School of Materials Science and Engineering Tongji UniversityShanghai 200240China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

LiNi0.8Co0.1Mn0.1O_(2)(NCM811),a Ni-rich layered oxide,is a promising cathode material for high-energy density lithium-ion batteries(LIBs).However,its structural instability,caused by adverse phase transitions and continuous oxygen release,as well as deteriorated interfacial stability due to excessive electrolyte oxidative decomposition,limits its widespread *** address these issues,a new concept is proposed that surface targeted precise functionalization(STPF)of the NCM811 cathode using a synergistic slurry additive(SSA)*** approach involves coating the NCM811 particle surface with 3-aminopropyl dimethoxy methyl silane(3-ADMS),followed by the precise deposition of ascorbic acid via an acid-base *** slurry additives induce the formation of an ultra-thin spinel surface layer and a stable cathode–electrolyte interface(CEI),which enhances the electrochemical kinetics and inhibits crack *** STPF strategy implemented by the SSA approach significantly improves the cyclic stability and rate performance of the NCM811 cathode in both half-cell and full-cell *** work establishes a promising strategy to enhance the structural stability and electrochemical performance of nickel-rich cathodes and provides a feasible route to promote practical applications of high-energy density lithium-ion battery technology.

关键词： nickel-rich cathode slurry additive lithium-ion battery cathode–electrolyte interface ascorbic acid phase transition

A Review on Flow Boiling of the Fluid with Lower Boiling Point in Micro-Channels

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Journal of Thermal Science 2024年第1期33卷 1-17页

作者： zhang Zhiqiang JIA Li DANG chao Beijing Key Laboratory of Flow and Heat Transfer of Phase Changing in Micro and Small Scale School of MechanicalElectronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China

With the advancement of micro machining technology,the high-heat-flux removal from miniature electronic devices and components has become an attractive *** boiling in micro-channels is an optimal form of heat transfer and has been widely employed in high-heat-flux cooling *** comprehensively-reviewed article focused on the available recent literatures of experimental investigation regarding the flow boiling heat transfer and unstable behaviors of the fluid with lower boiling point in *** thermal-fluid characteristics and potential heat transfer mechanisms of low-boiling-point fluids flow boiling in different narrow passages were summarized and *** literatures regarding the pressure drop and occurrence of the unstable phenomena existing in two-phase flow boiling process were also *** emphasis was given to the heat transfer enhancement methods as well as instability elimination,and various methods such as modification of surface and channel flow geometries were *** future researches in the field of micro-scale flow boiling were suggested.

关键词： flow boiling lower boiling point fluids mini/micro-channels instabilities enhancement suppression

Convolution Neural Network-based Load Model Parameter Selection Considering Short-term Voltage Stability

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1064-1074页

作者： Ying Wang chao Lu Xinran zhang School of Technology Beijing Forestry UniversityBeijing 100083China State Key Laboratory of Control and Simulation of Power System and Generation Equipment Tsinghua UniversityBeijing 100084China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100083China IEEE

The recently proposed ambient signal-based load modeling approach offers an important and effective idea to study the time-varying and distributed characteristics of power ***,it also brings new *** the load model parameters of power loads can be obtained in real-time for each load bus,the numerous identified parameters make parameter application *** order to obtain the parameters suitable for off-line applications,load model parameter selection(LMPS)is first introduced in this ***,the convolution neural network(CNN)is adopted to achieve the selection purpose from the perspective of short-term voltage *** begin with,the field phasor measurement unit(PMU)data from China Southern Power Grid are obtained for load model parameter identification,and the identification results of different substations during different times indicate the necessity of ***,the simulation case of Guangdong Power Grid shows the process of LMPS,and the results from the CNNbased LMPS confirm its effectiveness.

关键词： Ambient signal CNN field PMU data load model parameter selection short-term voltage stability