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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

PREPARATION AND PROPERTIES OF HIGH STrenGTH RODS FROM L-AND D,L-LACTIDE COPOLYMER

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Chinese Journal of Polymer Science 2001年第4期19卷 351-357页

作者： Yu-shan Hu Zheng-pu Zhang dong Song dong-ren bai Yong-mei Wang Institute of Polymer Chemistry State Key Laboratory of Functional Polymeric Materials for Adsorption and Separation, Nankai University Tianjin 300071, China Institute of Polymer Chemistry Stt. Key Lab. Funct. Polymeric M. Nankai University Tianjin 300071 China

Starling with the L- and D,L-lactide copolymer (L:DL = 9:1) [P(L-DL)LA] of M-W = 32.1 x 10(4), rods were obtained through a two stage process: (1) melt-extrusion at 155 degreesC, and (2) hot-drawing at 90 degreesC to various drawing ratios. The molecular weight of P(L-DL)LA fell to 9.3 x 10(4) as a consequence of the production process. The crystallization and molecular orientation of P(L-DL)LA developed as a result of the hot-drawing. The mechanical strengths of the rods increase with the drawing ratio; The maximum for tensile strength, bending strength, bending modulus, and shear strength are 329 MPa, 237 MPa, 8.8 GPa, and 157 MPa, respectively.

关键词： P(L-DL)LA self-reinforcement rod process bone fracture fixation

Internal electric field modulation by copper vacancy concentration of cuprous sulfide nanosheets for enhanced selective CO_(2) photoreduction

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Journal of Energy Chemistry 2024年第4期91卷 324-330页

作者： Xian Shi Weidong Dai Xiaoqian Li Yang bai Qin ren Yao Lei Xing'an dong School of Chemistry and Environmental Engineering Sichuan University of Science&EngineeringZigong 643000SichuanChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation School of Oil&Natural Gas EngineeringSouthwest Petroleum UniversityChengdu 610500SichuanChina Chongqing Key Laboratory of Photo-Electric Functional Materials College of Physics and Electronic EngineeringChongqing Normal UniversityChongqing 401331SichuanChina Research Center for Environmental and Energy Catalysis Institute of Fundamental and Frontier SciencesUniversity of Electronic Science and Technology of ChinaChengdu 611731SichuanChina

Although the internal electric field(IEF)of photocatalysts is acknowledged as a potent driving force for photocharge separation,modulating the IEF intensity to achieve enhanced photocatalytic performances remains a ***,cuprous sulfide nanosheets with different Cu vacancy concentration were employed to study IEF modulation and corresponding direct charge *** the samples,Cu_(1.8)S nanosheets possessed intensified IEF intensity compared with those of Cu_(2)S and Cu_(1.95)S nanosheets,suggesting that an enhanced IEF intensity could be achieved by introducing more Cu *** intensified IEF of Cu_(1.8)S nanosheets induced numerous photogenerated electrons to migrate to its surface,and the dissociative electrons were then captured by Cu vacancies,resulting in efficient charge separation *** addition,the Cu vacancies on Cu_(1.8)S nanosheets accumulated electrons as active sites to lower the energy barrier of rate-determining step of CO_(2)photoreduction,leading to the selective conversion of CO_(2)to ***,the manipulation of IEF intensity through Cu vacancy concentration regulation of cuprous sulfide photocatalysts for efficient charge separation has been discussed,providing a scientific strategy to rationally improve photocata lytic performances for solar energy conversion.

关键词： Internal electric field intensity Cuprous sulfide photocatalysts Cu vacancies Charge separation Selective CO_(2) photoreduction

Primitive functional groups directed distinct photocatalytic performance of imine-linked donor-acceptor covalent organic frameworks

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Nano Research 2024年第6期17卷 4994-5001页

作者： Xitong ren Jiajie Sun Yusen Li Feng bai Key Laboratory for Special Functional Materials of Ministry of Education National and Local Joint Engineering Research Center for High-Efficiency Display and Lighting TechnologySchool of Materials Science and Engineeringand Collaborative Innovation Center of Nano Functional Materials and ApplicationsHenan UniversityKaifeng 475004China School of Physics and Electronics Henan UniversityKaifeng 475004China

The combination of donor-acceptor(D-A)structures presents a viable strategy for fabricating covalent organic frameworks(COFs)with exceptional photocatalytic ***,the selection of functional groups on donor or acceptor building blocks and their effect on the macroscopic properties of COFs are *** this study,we tactfully synthesized a pair of Py-DBT-COFs from the same pyrene(Py)donor and 4,7-diphenylbenzo[c][1,2,5]thiadiazole(DBT)acceptor cores with distinct primitive functional *** primitive functional groups of building units determine the photocatalytic properties of corresponding ***,Py-C-DBT-COF synthesized from Py-4CHO and DBT-2NH_(2)showcases a splendid H_(2)evolution rate as high as 21,377.7μmol/(g·h)(with 5 wt.%Pt)originating from better charge transfer capacity,which is significantly superior to that of Py-N-DBT-COF constructed from Py-4NH_(2)and *** distinct photocatalytic performances of the two COFs are demonstrated to originate from the different charge separation and transfer *** work supplies a new avenue for optimizing the photocatalytic performance of D-A COFs from the perspective of primitive functional group selections.

关键词： covalent organic frameworks functional group donor-acceptor photocatalysis

Elemene Antitumor Drugs Development Based on "Molecular Compatibility Theory" and Clinical Application: A Retrospective and Prospective Outlook

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Chinese Journal of Integrative Medicine 2024年第1期30卷 62-74页

作者： JIANG Xiao-ying SHI Li-ping ZHU Jun-long bai ren-ren XIE Tian School of Pharmacy Hangzhou Normal UniversityHangzhou(311121)China Key Laboratory of Elemene Class Anti-cancer Chinese Medicines Engineering Laboratory of Development and Application of Traditional Chinese MedicinesCollaborative Innovation Center of Traditional Chinese Medicines of Zhejiang ProvinceHangzhou Normal UniversityHangzhou(311121)China Good Clinical Practice Center Affliliated Hospital of Nanjing University of Chinese MedicineNanjing(210000)China

Elemene, derived from Curcuma wenyujin, one of the "8 famous genuine medicinal materials of Zhejiang province," exhibits remarkable antitumor activity. It has gained wide recognition in clinical practice for effectiveness on tumors. Dr. XIE Tian introduced the innovative concept of "molecular compatibility theory" by combining Chinese medicine principles, specifically the "monarch, minister, assistant, and envoy" theory, with modern biomedical technology. This groundbreaking approach, along with a systematic analysis of Chinese medicine and modern biomedical knowledge, led to the development of elemene nanoliposome formulations. These novel formulations offer numerous advantages, including low toxicity, well-defined composition, synergistic effects on multiple targets, and excellent biocompatibility. Following the principles of the "molecular compatibility theory", further exploration of cancer treatment strategies and methods based on elemene was undertaken. This comprehensive review consolidates the current understanding of elemene's potential antitumor mechanisms, recent clinical investigations, advancements in drug delivery systems, and structural modifications. The ultimate goal of this review is to establish a solid theoretical foundation for researchers, empowering them to develop more effective antitumor drugs based on the principles of "molecular compatibility theory".

关键词： molecular compatibility theory Chinese integrative medicine elemene antitumor activity drug delivery structural modification

Observing eddy dye patches induced by shear instabilities in the surf zone on a plane beach

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Acta Oceanologica Sinica 2024年第3期43卷 15-29页

作者： Chunping ren Nannan Fu Chong Yu Yuchuan bai Kezhao Fang State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China College of Water Resource Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

The effects of surf zone eddy generated by alongshore currents on the deformation and transport of dye are still poorly understood,and related tracer release experiments are ***,a tracer release laboratory experiment was conducted under monochromatic,unidirectional incident waves with a large incident angle(30°)on a plane beach with a 1:100 slope in a large wave basin.A charge-coupled device suspended above the basin recorded the dye patch *** evolution of eddy dye patch was observed and the transport and diffusion were analyzed based on the collected ***,a linear instability numerical model was adopted to calculate the perturbation velocity field at the initial *** observation and image processing results show that surf zone eddy patches occurred and were separated from the original dye *** numerical analysis results demonstrate that the structure of the perturbation velocity field is consistent with the experimental observations,and that the ejection of eddy patches shoreward or offshore may be ascribed to the double vortex.

关键词： surf zone tracer release experiment evolution of eddy patch shear instability of alongshore currents

Weak Fault Feature Extraction of the Rotating Machinery Using Flexible Analytic Wavelet Transform and Nonlinear Quantum Permutation Entropy

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Computers, Materials & Continua 2024年第6期79卷 4513-4531页

作者： Lili bai Wenhui Li He ren Feng Li TaoYan Lirong Chen College of Aeronautics and Astronautics Taiyuan University of TechnologyTaiyuan030024China Commercial Aircraft Corporation of China Ltd.Shanghai200126China College of Physics and Electronic Engineering State Key Laboratory of Quantum Optics and Quantum Optics DevicesShanxi UniversityTaiyuan030006China

Addressing the challenges posed by the nonlinear and non-stationary vibrations in rotating machinery,where weak fault characteristic signals hinder accurate fault state representation,we propose a novel feature extraction method that combines the Flexible Analytic Wavelet Transform(FAWT)with Nonlinear Quantum Permutation ***,leveraging fractional orders and arbitrary scaling and translation factors,exhibits superior translational invariance and adjustable fundamental oscillatory *** flexibility enables FAWT to provide well-suited wavelet shapes,effectively matching subtle fault components and avoiding performance degradation associated with fixed frequency partitioning and low-oscillation bases in detecting weak *** our approach,gearbox vibration signals undergo FAWT to obtain *** theory is then introduced into permutation entropy to propose Nonlinear Quantum Permutation Entropy,a feature that more accurately characterizes the operational state of vibration simulation *** nonlinear quantum permutation entropy extracted from sub-bands is utilized to characterize the operating state of rotating machinery.A comprehensive analysis of vibration signals from rolling bearings and gearboxes validates the feasibility of the proposed *** assessments with parameters derived from traditional permutation entropy,sample entropy,wavelet transform(WT),and empirical mode decomposition(EMD)underscore the superior effectiveness of this approach in fault detection and classification for rotating machinery.

关键词： Rotating machinery quantum theory nonlinear quantum permutation entropy Flexible Analytic Wavelet Transform(FAWT) feature extraction

Hydrodynamic analysis of carbon nanotube clusters in distributor-less conical fluidized beds with step-by-step scaling

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Chinese Journal of Chemical Engineering 2024年第3期67卷 117-125页

作者： Tianle Zhang Wenjuan bai Qianpeng dong Dianming Chu Lianlian Wang Yan He Shandong Engineering Laboratory for Preparation and Application of High-performance Carbon-Materials College of Electromechanical EngineeringQingdao University of Science and TechnologyQingdao 266061China Shandong Dazhan Nano Materials Co. Ltd.Binzhou 256220China

As a high-performance material with great application potential,the application of carbon nanotubes has been limited by their production volume.A distributor-less conical fluidized bed is the main equipment used in the industrial production of carbon *** improve the production volume and product quality of carbon nanotubes,the study of fluidized-bed-diameter scaling is *** different diameters of distributor-less conical fluidized beds were established,and then the particle behavior and bubble characteristics of carbon nanotube clusters at these bed diameters were ***-series and wavelet analysis methods were used to analyze the pressure-fluctuation signals inside the fluidized *** showed that the distributor-less design caused the airflow to break through the middle of the bed,which did not change with the change in bed *** powder-bridging phenomenon of carbon nanotube clusters in a 100-mm-diameter fluidized bed was related to the special microstructure of carbon nanotube *** frequency of pressure fluctuations in the bed decreased nonlinearly with increasing bed *** study can guide the design and scale-up of distributor-less conical fluidized beds,especially for the scale-up of carbon nanotube production equipment,which can contribute to the improvement of carbon nanotubes’capacity and quality in industrial production.

关键词： Carbon nanotubes Fluidized bed Multiphase flow Scale-up Multiscale

Crack identification in concrete, using digital image correlation and neural network

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 536-550页

作者： Jingyi WANG dong LEI Kaiyang ZHOU Jintao HE Feipeng ZHU Pengxiang bai College of Mechanics and Materials Hohai UniversityNanjing 211100China

In engineering applications,concrete crack monitoring is very *** methods are of low efficiency,low accuracy,have poor timeliness,and are applicable in only a limited number of ***,more comprehensive detection of concrete damage under different scenarios is of high value for practical engineering *** image correlation(DIC)technology can provide a large amount of experimental data,and neural network(NN)can process very rich ***,NN,including convolutional neural networks(CNN)and back propagation neural networks(BP),can be combined with DIC technology to analyze experimental data of three-point bending of plain concrete and four-point bending of reinforced *** addition,strain parameters can be used for training,and displacement parameters can be added for comprehensive *** data obtained by DIC technology are grouped for training,and the recognition results of NN show that the combination of strain and displacement parameters,i.e.,the response of specimen surface and whole body,can make results more objective and *** identification results obtained by CNN and BP show that these technologies can accurately identify *** identification results for reinforced concrete specimens are less affected by noise than those of plain concrete *** is more convenient because it can identify some features directly from images,recognizing the cracks formed by macro *** can issue early warning of the microscopic cracks,but it requires a large amount of data and *** can be seen that CNN is more intuitive and efficient in image processing,and is suitable when low accuracy is adequate,while BP is suitable for occasions with greater accuracy *** two tools have advantages in different situations,and together they can play an important role in engineering monitoring.

关键词： digital image correlation convolutional neural network back propagation neural neural network damage detection concrete