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Nuclear Science and Techniques 2024年第2期35卷 170-182页

作者： Gao-Yi cheng Qian-Min Su Xi-guang Cao guo-Qiang Zhang School of Electronic and Electrical Engineering Shanghai University of Engineering ScienceShanghai 201620China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

Traditional particle identification methods face timeconsuming,experience-dependent,and poor repeatability challenges in heavy-ion collisions at low and intermediate energies.Researchers urgently need solutions to the dilemma of traditional particle identification methods.This study explores the possibility of applying intelligent learning algorithms to the particle identification of heavy-ion collisions at low and intermediate energies.Multiple intelligent algorithms,including XgBoost and TabNet,were selected to test datasets from the neutron ion multi-detector for reaction-oriented dynamics(NIMROD-ISiS)and Geant4 simulation.Tree-based machine learning algorithms and deep learning algorithms *** show excellent performance and generalization ability.Adding additional data features besides energy deposition can improve the algorithm’s performance when the data distribution is nonuniform.Intelligent learning algorithms can be applied to solve the particle identification problem in heavy-ion collisions at low and intermediate energies.

关键词： Heavy-ion collisions at low and intermediate energies Machine learning Ensemble learning algorithm Particle identification Data imbalance

T-tube bridging fistula jejunal anastomosis for treatment of pancreatic lumbar dorsal fistula after necrotizing pancreatitis

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Hepatobiliary & Pancreatic Diseases International 2024年第4期23卷 428-430页

作者： Su-Lai Liu guo-guang Li Wei cheng Chuang Peng Ying-Hui Song Department of Hepatobiliary Surgery Hunan Provincial People’s Hospital/The First Affiliated Hospital of Hunan Normal UniversityChangsha 410000China

Infectious pancreatic necrosis causes external pancreatic fistula in some patients.Generally,external pancreatic fistula requires fistula-gastric and/or intestinal anastomosis,and digestive endoscopic interventional treatment[1–3].It is especially difficult to treat external pancreatic fistulas with small fistulas where the external fistula is located in the lower back.The common treatment is to remove the body and tail of the pancreas and the spleen.This operation is very traumatic.A new pancreatic fistula may still occur at the pancreatic stump.The above operations may lead to unnecessary resection of the spleen,colon injury and other complications.In order to solve this problem,we innovatively used T-tube bridging fistula jejunal anastomosis plus continuous negative pressure suction to treat three cases of external pancreatic fistulas in the lower back,and all of them achieved good results.

关键词： fistula anastomosis spleen

Strengthening and control of second-phase particle precipitation in ferritic/austenitic/martensitic heat-resistant alloys:a review

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Journal of Iron and Steel Research(International) 2024年第1期31卷 3-23页

作者： Xue-cheng Peng Han-jie guo Xin-fang Zhang Yi-wa Luo Ye Sun Jing guo Rong-guang Yang Xiao-dan Zheng School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials University of Science and Technology Beijing(USTB)Beijing100083China Beijing Shougang Gitane New MATERIALS Co. Ltd.Beijing102206China

Heat-resistant alloys with excellent mechanical properties are widely used in various fields,and further improvement in their properties is essential to meet the requirements in new-generation advanced supercritical boilers,nuclear reactors,superheaters,and other new materials applications.To effectively enhance the comprehensive performance of heat-resistant alloys,second-phase particle strengthening has been widely studied,and in the face of different service envi-ronments of advanced heat-resistant steels,the selection of suitable second-phase particles is essential to maximize the performance of these alloys.To this end,three major types of reinforcing phases in heat-resistant alloys such as carbides,rare earth oxides,and intermetallic compounds are summarized.A comparative analysis of the precipitation behavior of the reinforcing phases with different types as well as the risks and means of controlling their use in service,is presented.Key parameters for the application of various types of second-phase particles in heat-resistant alloys are provided to support the design and preparation of new ultrahigh-performance heat-resistant alloys.

关键词： Heat-resistant alloy Second-phase particle Carbide Rare earth oxide Intermetallic compound Strengthening

Differentially private SGD with random features

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 1-23页

作者： WANG Yi-guang guo Zheng-chu Polytechnic Institute of Zhejiang University Zhejiang UniversityHangzhou 310015China School of Mathematical Sciences Zhejiang UniversityHangzhou 310058China

In the realm of large-scale machine learning,it is crucial to explore methods for reducing computational complexity and memory demands while maintaining generalization performance.Additionally,since the collected data may contain some sensitive information,it is also of great significance to study privacy-preserving machine learning algorithms.This paper focuses on the performance of the differentially private stochastic gradient descent(SGD)algorithm based on random features.To begin,the algorithm maps the original data into a lowdimensional space,thereby avoiding the traditional kernel method for large-scale data storage requirement.Subsequently,the algorithm iteratively optimizes parameters using the stochastic gradient descent approach.Lastly,the output perturbation mechanism is employed to introduce random noise,ensuring algorithmic privacy.We prove that the proposed algorithm satisfies the differential privacy while achieving fast convergence rates under some mild conditions.

关键词： learning theory differential privacy stochastic gradient descent random features reproducing kernel Hilbert spaces

Bioinspired design of integral molded Janus silk fibroin-MXene evaporator for efficient solar vapor generation

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Nano Research 2024年第4期17卷 2824-2835页

作者： Ling-Qing Kong Zhi-cheng Zeng guang-Zong Min Zhao-Hui Meng guo-Qing Meng Xiao-Xiao guo Nai-Bo Lin Xiang-Yang Liu The Higher Educational Key Laboratory for Biomedical Engineering of Fujian Province Research Center of Biomedical Engineering of XiamenDepartment of BiomaterialsCollege of MaterialsXiamen UniversityXiamen 361005China The State Key Laboratory of Marine Environmental Science(MEL) College of Ocean and Earth SciencesXiamen UniversityXiamen 361005China

Solar vapor generation is a promising sustainable technology that uses solar distillation to produce fresh water from seawater and wastewater,helping relieve global water resource shortage.Here,inspired by naturally grown integrally molded mulberry leaves with a Janus hydrophilic and hydrophobic structure,a novel,simple,and efficient integrated molding method is proposed to break through the limitations of the traditional split manufacturing strategy and realizes the integrated formation of Janus evaporator.Based on the spontaneous sedimentation characteristics of MXene in silk fibroin solution and its regulation of mesoscopic structure and hydrophilicity of silk fibroin,layered structures with different compositions and hydrophilicities were obtained in one step.Meanwhile,ethanol and glutaraldehyde were added to construct a physical crystallization-chemical crosslinking dual stabilization structure in silk fibroin.Our evaporator has the evaporation rate of 3.07 kg·m^(-2)·h^(-1) and the efficiency of 86.8%under 1 sun and maintains high evaporation performance under various extreme test conditions including vigorous washing,repeated compression,and high-intensity ultraviolet(UV)irradiation.Additionally,the evaporator performs well in practical application scenarios,its evaporation rate in the simulated Dead Sea seawater exceeds 2.13 kg·m^(-2)·h^(-1),and more than 99.9%of the salt,heavy metal ions,oil pollution,and dyes are purified.

关键词： silk fibroin MXene bioinspired integrated molding Janus structure solar vapor generation

A molecular insight into coke formation process of vacuum residue in thermal cracking reaction

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Petroleum Science 2024年第3期21卷 2130-2138页

作者： Ji-guang Li Xin guo Huan-Di Hou Heavy Oil Processing Department Sinopec Research Institute of Petroleum Processing Co. Ltd

Understanding the coking behaviors has been considered to be really essential for developing better vacuum residue processing technologies. A battery of thermal cracking tests of typical vacuum residue at410°C with various reaction time were performed to evaluate the coke formation process. The total yields of ideal components including naphtha, atmospheric gas oil(AGO) and vacuum gas oil(VGO) of thermal cracking reactions increased from 10.89% to 40.81%, and the conversion ratios increased from8.05% to 43.33% with increasing the reaction time from 10 to 70 min. The asphaltene content increased from 12.14% to a maximum of 22.39% and then decreased, and this maximum of asphaltene content occurred at the end of the coking induction period. The asphaltenes during the coking induction period,at the end and after coking induction period of those tested thermal cracking reactions were characterized to disclose the structure changing rules for coke formation process, and the coke formation pathways were discussed to reveal the coke formation process at molecular level.

关键词： Vacuum residue Thermal cracking Asphaltene Coking induction period Sulfur Nitrogen

The E3 ubiquitin ligase TRAF6 controls CTLA-4 turnover and promotes T-cell-mediated antitumor immunity

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Cellular & Molecular Immunology 2024年第1期21卷 97-99页

作者： Xiao-Liang Jie Hua guo guang-Biao Zhou State Key Laboratory of Molecular Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical College100021 BejingChina

Yu et al.[1]reported that the tumor necrosis factor(TNF)receptor OX40(CD134)-TNF receptor-associated factor 6(TRAF6)axis mediates Lys63-linked ubiquitination and subsequent lysosomal degradation of cytotoxic T-lymphocyte antigen 4(CTLA-4),leading to the enhancement of CD8^(+)T-cell-mediated antitumor immunity.Their findings unveil a previously unknown mechanism in controlling the stability of the immune checkpoint CTLA-4 and provide a potential therapeutic target for the improvement of Tcell-based immunotherapy.

关键词： immunity OX40 ubiquitin

A model reduction approach for discrete-time linear time-variant systems with delayed inputs

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Science China(Information Sciences) 2024年第4期67卷 197-217页

作者： Ai-guo WU guang-Ren DUAN Yu WANG Jie ZHANG School of Mechanical Engineering and Automation Harbin Institute of Technology(Shenzhen) HIT Wuhu Robot Technology Research Institute Center for Control Science and Technology Southern University of Science and Technology

A model reduction approach is presented for discrete-time linear time-variant input-delayed systems. According to this proposed approach, a dynamical variable is constructed by taking advantage of the current state and historical information of input. It is revealed that the behavior of this dynamical variable is governed by a discrete-time linear delay-free system. It is worth noting that the presented variable transformation does not require the system matrix to be invertible. Based on the reduced delay-free models,stabilizing control laws can be easily obtained for the original delayed system. For the case with a single input delay, the constructed variable is an exact prediction for the future state, and thus the stabilizing control law could be designed by replacing the future state with its prediction. Finally, three discrete-time periodic systems with delayed input are employed to illustrate how to utilize the presented model reduction approaches.

关键词： reduction approach predictor-based feedback time-varying systems delayed input periodic system

Effect of Al_(2)O_(3)/SiO_(2) mass ratio and CaO content on viscosity and structure of slag for pyrometallurgical processing of spent automotive catalysts

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Journal of Iron and Steel Research(International) 2024年第3期31卷 608-621页

作者： Zhe Wang Qi-long Wei cheng-bin Shi Zhan-cheng guo State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

The effect of Al_(2)O_(3)/SiO_(2) mass ratio and CaO content on the viscosity and structure of the CaO-Al_(2)O_(3)-SiO_(2)-6MgO-1.5ZrO_(2)-1.5CeO_(2) slag was investigated.The results show that with the increase in Al_(2)O_(3)/SiO_(2) mass ratio,the viscous flow units within the slag gradually change from Si-O-Si to Al-O-Al and Al-O-Si.Furthermore,the substitution of Al_(2)O_(3) for SiO_(2) leads to the transformation of Si-O bonds towards weaker Al-O bonds,which weaken the bond strength of the aluminosilicate networks,thus leading to a decrease in the viscosity of slag.The increase in CaO content effectively promotes the depolymerization of the aluminosilicate networks,resulting in a significant decrease in the viscosity of the slag.The slag with Al_(2)O_(3)/SiO_(2) of 0.7-1.5 and CaO of 30 wt.%shows promise as the reference slag system for the Fe-collection smelting of spent automotive catalysts due to its good comprehensive performance.

关键词： Aluminosilicate slag Al_(2)O_(3)/SiO_(2)mass ratio CaO content Viscosity Slag structure

A Novel Disturbance Observer Based Fixed-Time Sliding Mode Control for Robotic Manipulators With Global Fast Convergence

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 661-672页

作者： Dan Zhang Jiabin Hu Jun cheng Zheng-guang Wu Huaicheng Yan IEEE Zhejiang University of Technology guangxi Normal University Zhejiang University the East China University of Science and Technology

This paper proposes a new global fixed-time sliding mode control strategy for the trajectory tracking control of uncertain robotic manipulators.First,a fixed-time disturbance observer(FTDO) is designed to deal with the adverse effects of model uncertainties and external disturbances in the manipulator systems.Then an adaptive scheme is used and the adaptive FTDO(AFTDO) is developed,so that the priori knowledge of the lumped disturbance is not required.Further,a new non-singular fast terminal sliding mode(NFTSM) surface is designed by using an arctan function,which helps to overcome the singularity problem and enhance the robustness of the system.Based on the estimation of the lumped disturbance by the AFTDO,a fixed-time non-singular fast terminal sliding mode controller(FTNFTSMC)is developed to guarantee the trajectory tracking errors converge to zero within a fixed time.The settling time is independent of the initial state of the system.In addition,the stability of the AFTDO and FTNFTSMC is strictly proved by using Lyapunov method.Finally,the fixed-time NFESM(FTNFTSM) algorithm is validated on a 2-link manipulator and comparisons with other existing sliding mode controllers(SMCs) are performed.The comparative results confirm that the FTNFTSMC has superior control performance.

关键词： Disturbance observer(DO) fixed-time non-singular sliding mode control robotic manipulator trajectory tracking