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Reliable calculations of nuclear binding energies by the Gaussian process of machine learning

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Nuclear Science and Techniques 2024年第6期35卷 130-144页

作者： Zi-Yi Yuan dong Bai Zhen Wang Zhong-zhou Ren School of Physics Science and Engineering Tongji UniversityShanghai 200092China College of Science Hohai UniversityNanjing 211100China Key Laboratory of Advanced Micro-Structure Materials Ministry of EducationShanghai 200092China

Reliable calculations of nuclear binding energies are crucial for advancing the research of nuclear physics. Machine learning provides an innovative approach to exploring complex physical problems. In this study, the nuclear binding energies are modeled directly using a machine-learning method called the Gaussian process. First, the binding energies for 2238 nuclei with Z > 20 and N > 20 are calculated using the Gaussian process in a physically motivated feature space, yielding an average deviation of 0.046 MeV and a standard deviation of 0.066 MeV. The results show the good learning ability of the Gaussian process in the studies of binding energies. Then, the predictive power of the Gaussian process is studied by calculating the binding energies for 108 nuclei newly included in AME2020. The theoretical results are in good agreement with the experimental data, reflecting the good predictive power of the Gaussian process. Moreover, the α-decay energies for 1169 nuclei with 50 ≤ Z ≤ 110 are derived from the theoretical binding energies calculated using the Gaussian process. The average deviation and the standard deviation are, respectively, 0.047 MeV and 0.070 MeV. Noticeably, the calculated α-decay energies for the two new isotopes ^ (204 )Ac(Huang et al. Phys Lett B 834, 137484(2022)) and ^ (207) Th(Yang et al. Phys Rev C 105, L051302(2022)) agree well with the latest experimental data. These results demonstrate that the Gaussian process is reliable for the calculations of nuclear binding energies. Finally, the α-decay properties of some unknown actinide nuclei are predicted using the Gaussian process. The predicted results can be useful guides for future research on binding energies and α-decay properties.

关键词： Nuclear binding energies decay Machine learning Gaussian process

Tomographic particle image velocimetry measurement on three-dimensional swirling flow in dual-stage counter-rotating swirler

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Chinese Journal of Aeronautics 2024年第3期37卷 7-20页

作者： Yuyang zhou Ling dong Mingtao SHANG Jibao LI Akira RINOSHIKA Key Laboratory of Fluid Mechanics of Ministry of Education Beihang UniversityBeijing 100191China School of Mechanical and Automotive Engineering Shanghai University of Engineering ScienceShanghai 201620China AECC Commercial Aircraft Engine Co. Ltd.Shanghai 200241China Department of Mechanical Systems Engineering Yamagata UniversityYamagata 992-8510Japan

Three-Dimensional(3D)swirling flow structures,generated by a counter-rotating dualstage swirler in a confined chamber with a confinement ratio of 1.53,were experimentally investigated at Re=2.3×10^(5)using Tomographic Particle Image Velocimetry(Tomo-PIV)and planar Particle Image Velocimetry(PIV).Based on the analysis of the 3D time-averaged swirling flow structures and 3D Proper Orthogonal Decomposition(POD)of the Tomo-PIV data,typical coherent flow structures,including the Corner Recirculation Zone(CRZ),Central Recirculation Zone(CTRZ),and Lip Recirculation Zone(LRZ),were *** counter-rotating dual-stage swirler with a Venturi flare generates the independence process of vortex breakdown from the main stage and pilot stage,leading to the formation of an LRZ and a smaller CTRZ near the nozzle *** confinement squeezes the CRZ to the corner and causes a reverse rotation flow to limit the shape of the CTRZ.A large-scale flow structure caused by the main stage features an explosive breakup,flapping,and Precessing Vortex Core(PVC).The explosive breakup mode dominates the swirling flow structures owing to the expansion and construction of the main jet,whereas the flapping mode is related to the wake *** limits the expansion of PVC and causes it to contract after the impacting area.

关键词： Coherent structures Dual-stage counter-rotating swirler cup Precessing vortex core Proper orthogonal decomposition Swirling flow Tomographic particle image velocimetry

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蓄电池SOC平衡值对汽车能量流的影响研究

上海汽车 2024年第5期 23-30页

作者：徐红林方卢耀张振栋周栋孙晨上汽大众汽车有限公司上海201805

蓄电池SOC平衡值是为了维持整车电平衡,而用软件设定蓄电池SOC阈值,蓄电池SOC平衡值是控制发电机对蓄电池充电以及蓄电池放电的重要条件。对于SOC小于平衡值、SOC等于平衡值和SOC大于平衡值3种不同蓄电池状态的车辆进行WLTC试验,研究蓄... 详细信息

蓄电池SOC平衡值是为了维持整车电平衡,而用软件设定蓄电池SOC阈值,蓄电池SOC平衡值是控制发电机对蓄电池充电以及蓄电池放电的重要条件。对于SOC小于平衡值、SOC等于平衡值和SOC大于平衡值3种不同蓄电池状态的车辆进行WLTC试验,研究蓄电池SOC平衡值对车辆能量流的影响,特别是对车辆智能启停系统、能量回收系统的影响。研究表明:优化蓄电池SOC平衡值以及提高蓄电池的容量、峰值电流和电压以及发电机效率等措施,均可进一步优化车辆的能量管理,降低燃油车油耗。

关键词：蓄电池SOC平衡值能量流能量回收智能启停系统控制策略

电火花加工金刚石-镍复合电极制备参数优化研究

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模具技术 2024年第3期 57-63页

作者：王文建常皓拜颖乾赵涛周栋陕西铁路工程职业技术学院陕西渭南714000 郑州职业技术学院河南南郑州450000

研究了化学复合镀镀液的制备参数对复合电极制备的影响,阐述了金刚石微粉预处理步骤。分析了金刚石微粉的等效粒径对复合电极镀层的影响,得出最佳镀层金刚石等效粒径为10μm。进行了镀液温度变化下的复合电极制备速度关系试验,得出最佳... 详细信息

研究了化学复合镀镀液的制备参数对复合电极制备的影响,阐述了金刚石微粉预处理步骤。分析了金刚石微粉的等效粒径对复合电极镀层的影响,得出最佳镀层金刚石等效粒径为10μm。进行了镀液温度变化下的复合电极制备速度关系试验,得出最佳制备温度为74~76℃。对制备的电极进行加工试验,结果表明:参数优化复合电极的电极角损耗比普通紫铜电极降低了74.74%;参数优化复合电极的电极角损耗比参数未优化复合电极降低了57.29%。

关键词：电火花加工(EDM) 复合电极制备参数优化

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Phonon engineering significantly reducing thermal conductivity of thermoelectric materials: a review

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Rare Metals 2023年第9期42卷 2825-2839页

作者： Chuan-dong zhou Bo Liang Wen-Jie Huang Jacques-Guillaume Noudem Xiao-Jian Tan Jun Jiang State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004China ENSICAEN UNICEFCNRSCRISMATNormandie UniversityNormandie14000CaenFrance Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo315201China

Lattice thermal conductivity, κL, is a fundamental parameter for evaluating the performance of thermoelectric materials. However, the predicted value of κL based on the Debye dispersion model is often overestimated compared with the experimentally determined *** researchers have attempted to modify the theoretical model and have sought more reliable results. In this review,the recent progress in the study of phonon dispersion models is summarized and we propose that the lattice thermal conductivity can be most accurately determined by using the modified sinusoidal phonon dispersion ***, experimental methods that have the potential to reduce a thermoelectric material's κLare reviewed, for example, methods that generate standing waves or anharmonic lattice vibrations. A high concentration of standing waves and anharmonic lattice vibrations can effectively suppress excessive κL. Finally, this review presents the challenges of sinusoidal phonon dispersion when applied to real materials, which are often complicated and therefore time-consuming, especially when dealing with material defects.

关键词： Thermoelectric Lattice thermal conductivity Sinusoidal phonon dispersion model Standing wave Anharmonicity

A reweighted damped singular spectrum analysis method for robust seismic noise suppression

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Petroleum Science 2024年第3期21卷 1671-1682页

作者： Wei-Lin Huang Yan-Xin zhou Yang zhou Wei-Jie Liu Ji-dong Li State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing2249China SINOPEC Petroleum Exploration and Production Research Institute Beijing102206China SINOPEC Geophysical Research Institute Nanjing211103jiangsuChina

(Multichannel)Singular spectrum analysis is considered as one of the most effective methods for seismic incoherent noise *** utilizes the low-rank feature of seismic signal and regards the noise suppression as a low-rank reconstruction ***,in some cases the seismic geophones receive some erratic disturbances and the amplitudes are dramatically larger than other *** presence of this kind of noise,called erratic noise,makes singular spectrum analysis(SSA)reconstruction unstable and has undesirable effects on the final *** robustify the low-rank reconstruction of seismic data by a reweighted damped SSA(RD-SSA)*** incorporates the damped SSA,an improved version of SSA,into a reweighted *** damping operator is used to weaken the artificial disturbance introduced by the low-rank projection of both erratic and random *** central idea of the RD-SSA method is to iteratively approximate the observed data with the quadratic norm for the first iteration and the Tukeys bisquare norm for the rest *** RD-SSA method can suppress seismic incoherent noise and keep the reconstruction process robust to the erratic *** feasibility of RD-SSA is validated via both synthetic and field data examples.

关键词： Singular spectrum analysis Damping operator Seismic erratic noise Seismic signal processing Robust low-rank reconstruction

荆州地区回族与汉族胃癌及胃溃疡患者血液胃蛋白酶原水平比较

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医学信息 2024年第3期37卷 57-60页

作者：敖先伟陈小银孔繁静周东兵荆州市第二人民医院消化内科

目的研究血清胃蛋白酶原（PG）Ⅰ、PGⅡ及PGR值在荆州地区汉族及回族胃癌（GC）、胃溃疡（GU）患者中的意义，并探讨汉族与回族的差异。方法选取2016年1月-2021年6月在荆州市第二人民医院初次确诊的GC及GU患者共118例，按病种及民族... 详细信息

目的研究血清胃蛋白酶原（PG）Ⅰ、PGⅡ及PGR值在荆州地区汉族及回族胃癌（GC）、胃溃疡（GU）患者中的意义，并探讨汉族与回族的差异。方法选取2016年1月-2021年6月在荆州市第二人民医院初次确诊的GC及GU患者共118例，按病种及民族进行分组，其中汉族GC组30例，回族GC组28例，回族、汉族GU组各30例，比较各组PGⅠ、PGⅡ及PGR水平。结果汉族GC组及回族GC组血清PGⅠ、PGR水平低于同民族GU组，PGⅡ高于同民族GU组，差异均有统计学意义（P0.05），汉族GC组PGR水平低于回族GC组，差异有统计学意义（P0.05）。结论与GU患者比较，GC患者血清PGⅠ、PGR水平下降、PGⅡ升高，对本地区GC的筛查具有一定的临床意义。另外，汉族GU患者PGR水平低于回族GC患者，而汉族及回族GU患者PG水平无差异。

关键词：胃癌胃蛋白酶原回族荆州

Spontaneous acute epidural hematoma secondary to skull and dural metastasis of hepatocellular carcinoma: A case report

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World Journal of Clinical Cases 2022年第24期10卷 8728-8734页

作者： Guang-Zhao Lv Guo-Chao Li Wei-Tai Tang dong zhou Yong Yang Department of Neurosurgery Guangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesGuangzhou 510080Guangdong ProvinceChina Department of Neurosurgery Luoding People’s HospitalYunfu 527200Guangdong ProvinceChina

BACKGROUND The skull and dura are uncommon sites for the metastasis of hepatocellular carcinoma(HCC).Spontaneous acute epidural hematoma(AEDH)is also very *** report here a spontaneous AEDH secondary to skull and dural metastasis of *** case is extremely *** SUMMARY A 48-year-old male patient with a history of HCC developed unconsciousness *** computed tomography showed"a huge AEDH in the left parietal and occipital region with osteolytic destruction of the left parietal *** operation was performed to evacuate the hematoma and resect the *** study revealed that the lesion was the metastases from *** patient died of lung infection,anemia,and liver failure 3 wk after *** Spontaneous AEDH caused by hepatocellular carcinoma(HCC)dural and skull metastases is extremely rare,the outcome is ***,early diagnosis is *** the level of AFP does not decrease with the shrinkage of intrahepatic lesions after treatment,it is necessary to be alert to the existence of extrahepatic *** most of the patients had scalp and bone masses,physicians should pay attention to the patient's head *** a patient with the history of HCC had sudden neurological dysfunction,the possibility of spontaneous AEDH caused by the skull and dura mater metastases should be *** hemorrhage is common in the skull HCC metastases,for patients with spontaneous AEDH accompanied by skull osteolytic lesions,it is also necessary to be alert to the possibility of *** AEDH secondary to HCC metastases,early diagnosis and timely treatment are critical to improve the patients’outcomes.

关键词： Spontaneous acute epidural hematoma Hepatocellular carcinoma Skull and dural metastasis Case report

High‑Energy Room‑Temperature Sodium–Sulfur and Sodium–Selenium Batteries for Sustainable Energy Storage

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Electrochemical Energy Reviews 2023年第1期6卷 87-147页

作者： Zefu Huang Pauline Jaumaux Bing Sun Xin Guo dong zhou Devaraj Shanmukaraj Michel Armand Teofilo Rojo Guoxiu Wang Centre for Clean Energy Technology School of Mathematical and Physical SciencesFaculty of ScienceUniversity of Technology SydneyUltimoNSW 2007Australia Centre for Cooperative Research on Alternative Energies(CIC energiGUNE) Basque Research and Technology Alliance(BRTA)Alava Technology ParkAlbert Einstein 4801510 Vitoria-GasteizSpain Inorganic Chemistry Department University of the Basque Country UPV/EHUP.O.Box.64448080 BilbaoSpain

Rechargeable room-temperature sodium–sulfur(Na–S)and sodium–selenium(Na–Se)batteries are gaining extensive attention for potential large-scale energy storage applications owing to their low cost and high theoretical energy *** of electrode materials and investigation of mechanisms are essential to achieve high energy density and long-term cycling stability of Na–S(Se)***,we provide a comprehensive review of the recent progress in Na–S(Se)*** elucidate the Na storage mechanisms and improvement strategies for battery *** particular,we discuss the advances in the development of battery components,including high-performance sulfur cathodes,optimized electrolytes,advanced Na metal anodes and modified *** with current research achievements,this review outlines remaining challenges and clear research directions for the future development of practical high-performance Na–S(Se)batteries.

关键词： Sodium-sulfur batteries Sodium-selenium batteries Sulfur cathodes Electrolyte engineering Solid-state electrolytes Sodium metal anodes