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Neutron star mass-radius relation with gravitational field shielding by a scalar field

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Research in Astronomy and Astrophysics 2013年第5期13卷 571-578页

作者： Bo-Jun zhang tian-xi zhang Padmaja Guggilla Mostafa Dokhanian Department of Physics and Astronomy Vanderbilt University Department of Physics Alabama A & M University National Astronomical Observatories Chinese Academy of Sciences

The currently well-developed models for equations of state （EoSs） have been severely impacted by recent measurements of neutron stars with a small radius and/or large mass. To explain these measurements, the theory of gravitational field shielding by a scalar field is applied. This theory was recently developed in accor- dance with the five-dimensional （5D） fully covariant Kaluza-Klein （KK） theory that has successfully unified Einstein＇s general relativity and Maxwell＇s electromagnetic theory. It is shown that a massive, compact neutron star can generate a strong scalar field, which can significantly shield or reduce its gravitational field, thus making it more massive and more compact. The mass-radius relation developed under this type of modified gravity can be consistent with these recent measurements of neutron stars. In addition, the effect of gravitational field shielding helps explain why the supernova explosions of some very massive stars （e.g.9 40 MQ as measured recently） actually formed neutron stars rather than black holes as expected. The EoS models, ruled out by measurements of small radius and/or large mass neutron stars according to the the- ory of general relativity, can still work well in terms of the 5D fully covariant KK theory with a scalar field.

关键词： stars: neutron -- gravitation -- black hole physics -- equation of state

Towards full demonstration of high areal loading sulfur cathode in lithium–sulfur batteries

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Journal of Energy Chemistry 2019年第12期28卷 17-22页

作者： Long Kong Qi Jin xi-tian zhang Bo-Quan Li Jin-xiu Chen Wan-Cheng Zhu Jia-Qi Huang Qiang zhang Beijing Key Laboratory o f Green Chemical Reaction Engineering and Technology Department of Chemical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Physics and Electronic EngineeringHarbin Normal UniversityHarbin 150025HeilongjiangChina Department of Chemical Engineering Qufu Normal UniversityQufu 273165ShandongChina Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China

Lithium–sulfur(Li–S)batteries have been recognized as promising substitutes for current energy-storage technologies owing to their exceptional advantages in very high-energy density and excellent material *** cathode with high sulfur areal loading is vital for the practical applications of Li–S batteries with very high energy ***,the high sulfur loading in an electrode results in poor rate and cycling performances of batteries in most ***,we used diameters of 5.0(D5)and 13.0(D13)mm to probe the effect of electrodes with different sizes on the rate and cycling performances under a high sulfur loading(4.5 mg cm^-2).The cell with D5 sulfur cathode exhibits better rate and cycling performances comparing with a large(D13)*** the high concentration of lithium polysulfides and corrosion of lithium metal anode impede rapid kinetics of sulfur redox reactions,which results in inferior battery performance of the Li–S cell with large diameter *** work highlights the importance of rational matching of the large sulfur cathode with a high areal sulfur loading,carbon modified separators,organic electrolyte,and Li metal anode in a pouch cell,wherein the sulfur redox kinetics and lithium metal protection should be carefully considered under the flooded lithium polysulfide conditions in a working Li–S battery.

关键词： Lithium sulfur batteries High areal sulfur loading Lithium anode protection Sulfur redox reactions Polysulfide interm ediates

First-principles study of high performance lithium/sodium storage of Ti3C2T2 nanosheets as electrode materials

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Chinese Physics B 2020年第1期29卷 398-407页

作者： Li-Na Bai Ling-Ying Kong Jing Wen Ning Ma Hong Gao xi-tian zhang Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Physics and Electronic EngineeringHarbin Normal UniversityHarbin 150025China School of Computer Science and Information Engineering Harbin Normal UniversityHarbin 150025China Department of Physics Harbin Institute of TechnologyHarbin 150001China

Ti3C2Tx nanosheet,the first synthesized MXene with high capacity performance and charge/discharge rate,has attracted increasingly attention in renewable energy storage *** performing systematic density functional theory calculations,the theoretical capacity of the intrinsic structure of single-and multi-layered Ti3C2T2(T=F or O)corresponding to M(M=Li and Na)atoms are *** volumetric capacity and gravimetric capacity are obtained,which are related to the stacking *** optimal ratios of capacity to structure are determined under different stacking degrees for understanding the influence of surface functional groups on energy storage *** performance can be tuned by performing surface modification and increasing the interlayer *** addition,the reason for theoretical capacity differences of M atoms is analyzed,which is attributed to difference in interaction between the M-ions and substrate and the difference in electrostatic exclusion between adsorbed *** results provide an insight into the understanding of the method of efficiently increasing the energy storage performance,which will be useful for designing and using high performance electrode materials.

关键词： density functional theory MXene electrode materials

DYNAMIC NMR STUDIES ON [Li(2D)][Nd(η~3-C_3H_5)_4]

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Chinese Chemical Letters 1993年第2期4卷 187-188页

作者： Feng Fu LI xi tian zhang Ying Tai JIN Feng Kui PEI Changchun Institute of Applied Chemistry Academia Sinica Changchun130022

The dynamic ~1H and ^(13)C-NMR studies on [Li(2D)][Nd(η~8-C_3H_5)_4] (D=dioxane)were reported The four allyls coordinated to Hd^(8+) ion are equivalent and hydrogens appear as three groups in ~1H-NMR spectra with their chemical shifts changing with temperature.C_1 and Ca are equivalent showing the characteristic of η~2=-*** paramagnetic shifts of carbons in allyls induced by Nd^(2+) ere separated sucessfully.C_1 and C_3 located on the zero-dipolar *** content of contact shift is greater than that of dipolar slift to Co.

关键词： NMR C3H5 DYNAMIC NMR STUDIES ON Li Nd

Modeling and Capacity Configuration Optimization of CRH5 EMU On-Board Energy Storage System

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Energy Engineering 2025年第1期122卷 307-329页

作者： Mingxing tian Weiyuan zhang Zhaoxu Su School of Automation and Electrical Engineering Lanzhou Jiaotong UniversityLanzhou730070China

In the context of the“dual carbon”goals,to address issues such as high energy consumption,high costs,and low power quality in the rapid development of electrified railways,this study focused on the China Railways High-Speed 5 Electric Multiple Unit and proposed a mathematical model and capacity optimization method for an onboard energy storage system using lithium batteries and supercapacitors as storage ***,considering the electrical characteristics,weight,and volume of the storage media,a mathematical model of the energy storage system was ***,to tackle problems related to energy consumption and power quality,an energy management strategy was proposed that comprehensively considers peak shaving and valley filling and power quality by controlling the charge/discharge thresholds of the storage *** optimization adopted a bilevel programming model,with the series/parallel number of storage modules as variables,considering constraints imposed by the Direct Current to Direct Current converter,train load,and *** improved Particle Swarm Optimization algorithm and linear programming solver were used to solve specific *** results show that the proposed onboard energy storage system can effectively achieve energy savings,reduce consumption,and improve power qualitywhile meeting the load and space limitations of the train.

关键词： Electrified railway regenerative braking bi-level programming on-board energy storage power quality capacity configuration

DYNAMIC NMR STUDIES ON [Li（3D）] [La（η3-C3H5）4]

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Chinese Chemical Letters 1994年第5期 393-394页

作者： Feng Fu LI Ying Tai JIN xi tian zhang Feng Kui PEI (Changchun Institute of Applied Chemistry, Chinese Academy of Sciences,Changchun, 130022)

ＹＮＡＭＩＣＮＭＲＳＴＵＤＩＥＳＯＮ［Ｌｉ（３Ｄ）］［Ｌａ（η３－Ｃ３Ｈ５）４］￥ＦｅｎｇＦｕＬＩ；ＹｉｎｇＴａｉＪＩＮ；ＸｉＴｉａｎＺＨＡＮＧ；ＦｅｎｇＫｕｉＰＥＩ(ＣｈａｎｇｃｈｕｎＩｎｓｔｉｔｕｔｅｏｆＡｐｐｌ... 详细信息

ＹＮＡＭＩＣＮＭＲＳＴＵＤＩＥＳＯＮ［Ｌｉ（３Ｄ）］［Ｌａ（η３－Ｃ３Ｈ５）４］￥ＦｅｎｇＦｕＬＩ；ＹｉｎｇＴａｉＪＩＮ；ＸｉＴｉａｎＺＨＡＮＧ；ＦｅｎｇＫｕｉＰＥＩ(ＣｈａｎｇｃｈｕｎＩｎｓｔｉｔｕｔｅｏｆＡｐｐｌｉｅｄＣｈｅｍｉｓｔｒｙ，Ｃｈ...

关键词： NMR Li C3H5 DYNAMIC NMR STUDIES ON La

Optimizing battery deployment: Aging trajectory prediction enabling homogenous performance grouping

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Journal of Energy Chemistry 2025年第1期100卷 565-577页

作者： Shuquan Wang Feng Gao Zhan Ma Hao tian Yusen zhang School of Control Science and Engineering Shandong University Key Lab of Power System Intelligent Dispatch and Control of Ministry of Education Shandong University

As battery deployments in electric vehicles and energy storage systems grow, ensuring homogeneous performance across units is crucial. We propose a multi-derivative imaging fusion(MDIF) model, employing advanced imaging and machine learning to predict battery aging trajectories from minimal initial data, thus facilitating effective performance grouping before deployment. Utilizing a derivative strategy and Gramian Angular Difference Field for dimensional enhancement, the MDIF model uncovers subtle predictive features from discharge curve data after only ten cycles. The architecture includes a parallel convolutional neural network with lateral connections to enhance feature integration and *** on a self-developed dataset, the model achieves an average root-mean-square error of 0.047 Ah and an average mean absolute percentage error of 1.60%, demonstrating high precision and *** robustness is further validated through transfer learning on two publicly available datasets, adapting with minimal retraining. This approach significantly reduces the testing cycles required, lowering both time and costs associated with battery testing. By enabling precise battery behavior predictions with limited data, the MDIF model optimizes battery utilization and deployment strategies, enhancing system efficiency and sustainability.

关键词： Lithium-ion battery Battery prognostics Fusion model Convolutional neural network Transfer learning

Interventional treatment experience in multiple injury with major abdominal or pelvic injuries： 160 cases analysis

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Chinese Journal of Traumatology 2018年第1期21卷 27-29页

作者： tian-xi zhang Mei Han Peng Ye Quan Hu Jia-Lin Li Ling Yin An-Yong Yu Department of Emergency The First Affiliated Hospital of Zunyi Medical College Zunyi 563003 Guizhou Province China

Purpose： To observe the therapeutic effect of interventional embolization and haemorrhage control in multiple trauma patients with a major abdominal or pelvic injury. Methods： Data of 160 multiple trauma patients with a major abdominal or pelvic injury were retro- spectively analyzed. They were admitted into the Department of Emergency of the First Affiliated Hospital of Zunyi Medical College from October 2013 to April 2016. Eighty-seven patients who received emergent intervention for embolization and haemorrhage control were set as group A, including 72 males and 15 females, with an average age of （39.32 ±14.0） years. Patients underwent emergent intervention for embolization and hemostasis. The other 73 patients who received traditional surgeries were set as group B, including 62 males and 11 females, with an average age of （38.48 ± 13.12） years. The time from admission to emergency intervention, the time of interventional embolization, transfusion during hospitalization, length of stay and prognosis were observed. The whole treatment and prognosis were compared between group A and group B. Results： In group A, the average time from admission to intervention exploration was （132.05 ± 86.80） min, the average operation time was （149 ± 49.69） min, the average hospitalization time was （18.37±4.71 ） days, the average amount of RBC transfusion during hospitalization was （Z2 ± 4.33） units, and the mortality was 4.60% （4 patients died）. The corresponding data in group B were respectively （138.95± 82.49） min, （183 ± 52.39） min, （22.72 ± 6.63） days, （12.23 ± 5.43） units, and 9.59% （7 cases died）. There was no statistical difference in the time from admission to operation between the two groups （p 〉 0.05）, but there was statistical difference in operation time, RBC transfusion, hospitalization time, prognosis, and mortality between the two groups （all p 〈 0.05）. Conclusion： The emergent intervention for embolization and haemorrhage control of multiple trauma patients with a m

关键词： Abdominal injury Multiple trauma Embolization Haemorrhage Prognosis

Structural Modal Parameter Recognition and Related Damage Identification Methods under Environmental Excitations: A Review

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Structural Durability & Health Monitoring 2025年第1期19卷 25-54页

作者： Chao zhang Shang-xi Lai Hua-Ping Wang School of Civil Engineering and Mechanics Lanzhou UniversityLanzhou730000China Key Laboratory of Special Functional Materials and Structural Design Ministry of EducationLanzhou UniversityLanzhou730000China

Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the ***,it is particularly signiﬁcant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientiﬁc basis for structural damage identiﬁcation and dynamic model modiﬁ*** view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and brieﬂy describes how to identify structural damages based on the derived modal *** paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),brieﬂy describes damage identiﬁcation methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artiﬁcial intelligence(AI)methods in the direction of modal parameter recognition and damage identiﬁcation is further *** on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identiﬁcation methods are given to provide scientiﬁc references for the optimized design and functional upgrading of SHM systems.

关键词： Structural health monitoring data information modal parameters damage identiﬁcation AI method