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Gas–solid reactor optimization based on EMMS-DPM simulation and machine learning

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Particuology 2024年第6期89卷 131-143页

作者： Haolei Zhang Aiqi Zhu ji xu Wei Ge State Key Laboratory of Mesoscience and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China

Design,scaling-up,and optimization of industrial reactors mainly depend on step-by-step experiments and engineering experience,which is usually time-consuming,high cost,and high *** numerical simulation can reproduce high resolution details of hydrodynamics,thermal transfer,and reaction process in reactors,it is still challenging for industrial reactors due to huge computational *** this study,by combining the numerical simulation and artificial intelligence(AI)technology of machine learning(ML),a method is proposed to efficiently predict and optimize the performance of industrial reactors.A gas–solid fluidization reactor for the methanol to olefins process is taken as an example.1500 cases under different conditions are simulated by the coarse-grain discrete particle method based on the Energy-Minimization Multi-Scale model,and thus,the reactor performance data set is *** develop an efficient reactor performance prediction model influenced by multiple factors,the ML method is established including the ensemble learning strategy and automatic hyperparameter optimization technique,which has better performance than the methods based on the artificial neural ***,the operating conditions for highest yield of ethylene and propylene or lowest pressure drop are searched with the particle swarm optimization algorithm due to its strength to solve non-linear optimization *** show that decreasing the methanol inflow rate and increasing the catalyst inventory can maximize the yield,while decreasing methanol the inflow rate and reducing the catalyst inventory can minimize the pressure *** two objectives are thus conflicting,and the practical operations need to be compromised under different circumstance.

关键词： Discrete particle method Artificial intelligence Machine learning Particle swarm optimization Industrial reactor optimization

3D coarse-grained DPM simulation of the MIP reaction-regeneration loop

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Particuology 2024年第6期89卷 57-66页

作者： Yanhao Ye Shuai Zhang ji xu Wei Ge State Key Laboratory of Mesoscience and Engineering(formerly State Key Laboratory of Multiphase Complex Systems) Institute of Process EngineeringChinese Academy of SciencesBeijing100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing100049China

The reactor-regenerator loop is the core facility of the maximizing iso-paraffin(MIP)*** the discrete particle method(DPM)simulation can provide detailed information at the particle scale,it has been unable to simulate such a complex loop system due to limitations of coarse-grained(CG)models,computing software,and *** this study,a newly proposed soft-shell CG-DPM model with a CG ratio of up to 800 is used to simulate a 3.5 Mt/a industrial-scale MIP reactor-regenerator *** solid fraction distribution obtained is found to agree well with in-situ *** properties including the distribution of solid fraction,gas and solid velocity,standard derivation of solid fraction with time,temporal distribution of the flow field,and particle residence time distribution are measured in the simulation,which are meaningful to better design and operate such systems in the future.

关键词： Discrete particle method Coarse-grain Maximizing iso-paraffins Full-loop Reaction-regeneration system

Cyclic Beam Direction of Arrival Estimation Method for Ship Propeller Noise

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JOURNAL OF OCEAN UNIVERSITY OF CHINA 2024年第4期23卷 883-896页

作者： Zhang, Xiaowei Nie, Weihang xu, ji Yan, Yonghong Chinese Acad Sci Key Lab Speech Acoust & Content Understanding Inst Acoust Beijing 100190 Peoples R China Univ Chinese Acad Sci Inst Acoust Key Lab Speech Acoust & Content Understanding Beijing 100049 Peoples R China Chinese Acad Sci State Key Lab Acoust Inst Acoust Beijing 100190 Peoples R China

In underwater acoustic applications, the conventional cyclic direction of arrival algorithm faces challenges, including a low signal-to-noise ratio and high bandwidth when compared with modulated frequencies. In response to these issues, this paper introduces a novel, robust, and broadband cyclic beamforming algorithm. The proposed method substitutes the conventional cyclic covariance matrix with the variance of the cyclic covariance matrix as its primary feature. Assuming that the same frequency band shares a common steering vector, the new algorithm achieves superior detection performance for targets with specific modulation frequencies while suppressing interference signals and background noise. Experimental results demonstrate a significant enhancement in the directibity index by 81% and 181% when compared with the traditional Capon beamforming algorithm and the traditional extended wideband spectral cyclic MUSIC (EWSCM) algorithm, respectively. Moreover, the proposed algorithm substantially reduces computational complexity to 1/40th of that of the EWSCM algorithm, employing frequency band statistical averaging and covariance matrix variance.

关键词： cyclostationarity direction of arrival extended wideband spectral cyclic music cyclic covariance matrix MUSIC CYCLOSTATIONARITY EXPLOITATION

Simulation of the L-valve in the circulating fluidized bed with a coarse-grained discrete particle method

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Particuology 2024年第7期90卷 266-280页

作者： Ruixiang Tang Zheng Zou ji xu Junwu Wang Qingshan Zhu Hongzhong Li State Key Laboratory of Mesoscience and Engineering Institute of Process EngineeringChinese Academy of SciencesP.O.Box 353Beijing100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing100049China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing100190China

Stable and controllable solid flow is essential in circulating fluidized bed (CFB) systems. The L-valve is a typical non-mechanical valve that can provide flexible solid feeding. The investigation of the solid circulation rate and the hydrodynamic characteristics of the L-valve is crucial to its design and operation. The gas-solid flow in the L-valve of a full-loop CFB is studied with the coarse-grained discrete particle method (EMMS-DPM). Good agreements on the solid circulation rate and the pressure drop through the L-valve are achieved between the simulated and experimental data. The solid circulation rate increases linearly with the aeration velocity until the stable particle circulation of the CFB is destroyed. The flow patterns in the horizontal section of L-valve are gas-solid slug flow above the stationary solid layer and the moving solid layer, respectively. The effects of L-valve geometric parameters on the solid flow characteristics are also investigated. The results indicate that reducing the diameter and length of the horizontal section of L-valve can improve the solid transport efficiency, especially at low aeration velocity. Besides, the solid conveying capacity and flow stability are improved when the sharp bend of L-valve is modified to be a gradual bend.

关键词： L-valve Circulating fluidized bed Full loop Discrete particle method Gas-solid flow

Causal temporal graph attention network for fault diagnosis of chemical processes

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Chinese Journal of Chemical Engineering 2024年第6期70卷 20-32页

作者： jiaojiao Luo Zhehao jin Heping jin Qian Li xu ji Yiyang Dai School of Chemical Engineering Sichuan UniversityChengdu 610065China China Three Gorges Corporation Beijing 100038China

Fault detection and diagnosis(FDD)plays a significant role in ensuring the safety and stability of chemical *** the development of artificial intelligence(AI)and big data technologies,data-driven approaches with excellent performance are widely used for FDD in chemical ***,improved predictive accuracy has often been achieved through increased model complexity,which turns models into black-box methods and causes uncertainty regarding their *** this study,a causal temporal graph attention network(CTGAN)is proposed for fault diagnosis of chemical processes.A chemical causal graph is built by causal inference to represent the propagation path of *** attention mechanism and chemical causal graph were combined to help us notice the key variables relating to fault *** in the Tennessee Eastman(TE)process and the green ammonia(GA)process showed that CTGAN achieved high performance and good explainability.

关键词： Chemical processes Safety Fault diagnosis Causal discovery Attention mechanism Explainability

Nd:YAG water mist laser treatment for giant gestational gingival tumor: A case report

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World Journal of Clinical Cases 2024年第11期12卷 1974-1979页

作者： Hong-Yu Chen Jun-ji xu Xiu-Lin Chang Pei Wu Department of Stomatology Women and Children's Hospital Affiliated to Ningbo UniversityNingbo 315012Zhejiang ProvinceChina

BACKGROUND This case of gestational gingival tumor is huge and extremely rare in clinical *** the growth location of this gingival tumor is in the upper anterior tooth area,it seriously affects the pregnant woman's speech and food,causing great pain to the *** use of Nd:YGA water mist laser to remove the gingival tumor resulted in minimal intraoperative bleeding,minimal adverse reactions,and good postoperative healing,which is worthy of clinical promotion and *** SUMMARY The patient,a pregnant woman,reported a large lump in her mouth on the first day of postpartum *** on medical history and clinical examination,the diagnosis was diagnosed as gestational gingival *** pathological biopsy also confirmed this *** use of Nd:YAG water mist laser to remove the tumor resulted in minimal intraoperative bleeding,clear surgical field of view,short surgical time,and good postoperative *** In comparison to traditional surgery,Nd:YAG water mist laser surgery is minimally invasive,minimizes cell damage,reduces bleeding,ensures a clear field of vision,and virtually eliminates postoperative edema,carbonization,and the risk of cross *** has unique advantages in oral soft tissue surgery for pregnant ***,the clinical application of Nd:YAG water mist laser for the treatment of gestational gingival tumors is an ideal choice.

关键词： Gestational gingival tumor Nd:YAG water mist laser Granulomatous gingival tumor Minimally invasive dentistry Pregnancy related diseases Oral soft tissue surgery Case report

Production of charmonium pentaquarks from b-baryon and B-meson decays:SU(3)analysis

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Chinese Physics C 2024年第5期48卷 107-116页

作者：韩伟毫邢晔徐吉 School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China School of Physics China University of Mining and TechnologyXuzhou 221000China

Here,we study the production of charmonium pentaquarks cc¯qqq from bottom baryon and B-meson decays under the flavor SU(3)*** amplitudes for various processes are parameterized in terms of SU(3)irreducible nonperturbative *** relations between decay widths are ***,the strong decays of pentaquarks are *** results can be tested in future measurements at LHCb,Belle II,and *** decay branching fractions are measured,this study will be useful for the exploration of new decay channels and pentaquark states.

关键词： pentaquark SU(3)symmetry decay

Effects of interleukin-10 treated macrophages on bone marrow mesenchymal stem cells via signal transducer and activator of transcription 3 pathway

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World Journal of Stem Cells 2024年第5期16卷 560-574页

作者： Meng-Hao Lyu Ce Bian Yi-Ping Dou Kang Gao Jun-ji xu Pan Ma Department of Periodontics School of StomatologyCapital Medical UniversityBeijing 100050China Department of Orthodontics School of StomatologyCapital Medical UniversityBeijing 100050China Department of Dental Implantology School of StomatologyCapital Medical UniversityBeijing 100050China Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction School of StomatologyCapital Medical UniversityBeijing 100050China Beijing Laboratory of Oral Health Capital Medical UniversityBeijing 100050China

BACKGROUND Alveolar bone defects caused by inflammation are an urgent issue in oral implant surgery that must be *** the various phenotypes of macrophages to enhance the inflammatory environment can significantly affect the progression of diseases and tissue engineering repair *** To assess the influence of interleukin-10(IL-10)on the osteogenic differentiation of bone marrow mesenchymal stem cells(BMSCs)following their interaction with macrophages in an inflammatory *** IL-10 modulates the differentiation of peritoneal macrophages in Wistar rats in an inflammatory *** this study,we investigated its impact on the proliferation,migration,and osteogenesis of *** expression levels of signal transducer and activator of transcription 3(STAT3)and its activated form,phos-phorylated-STAT3,were examined in IL-10-stimulated ***,a specific STAT3 signaling inhibitor was used to impede STAT3 signal activation to further investigate the role of STAT3 *** IL-10-stimulated macrophages underwent polarization to the M2 type through substitution,and these M2 macrophages actively facilitated the osteogenic differentiation of ***,STAT3 signaling plays a crucial role in the process by which IL-10 influences ***,IL-10 stimulated the activation of the STAT3 signaling pathway and reduced the macrophage inflammatory response,as evidenced by its diminished impact on the osteogenic differentiation of *** Stimulating macrophages with IL-10 proved effective in improving the inflammatory environment and promoting the osteogenic differentiation of *** IL-10/STAT3 signaling pathway has emerged as a key regulator in the macrophage-mediated control of BMSCs’osteogenic differentiation.

关键词： Macrophages Interleukin-10 Bone marrow mesenchymal stem cells Signal transducer and activator of transcription 3 Inflammatory response

Neutrophil-to-lymphocyte ratio associated with renal function in type 2 diabetic patients

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World Journal of Clinical Cases 2024年第14期12卷 2308-2315页

作者： jin-Li Gao Jue Shen Li-Ping Yang Li Liu Kai Zhao Xiao-Rong Pan Lei Li ji-ji xu Department of Prevention and Health Care Community Health Service Center of Miaohang TownShanghai 200443China Department of Prevention and Health Care Community Health Service Center of Songnan TownShanghai 200434China Department of General Practice Community Health Service Center of Songnan TownShanghai 200434China Department of Administrative Community Health Service Center of Songnan TownShanghai 200434China

BACKGROUND Type 2 diabetes mellitus(T2DM)is a leading risk factor for the development and progression of chronic kidney disease(CKD).However,an accurate and con-venient marker for early detection and appropriate management of CKD in in-dividuals with T2DM is *** studies have demonstrated a strong correlation between the neutrophil-to-lymphocyte ratio(NLR)and ***-theless,the predictive value of NLR for renal damage in type 2 diabetic patients remains *** study included 1040 adults aged 65 or older with T2DM from Shanghai's Community Health Service *** total number of neutrophils and lym-phocytes was detected,and NLR levels were *** was defined as an estimated glomerular filtration rate≤60 mL/min/1.73 m².Participants were di-vided into four groups based on NLR *** clinical data and biochemical characteristics were compared among groups.A multivariate logistic regression model was used to analyze the association between NLR levels and *** Significant differences were found in terms of sex,serum creatinine,blood urea nitrogen,total cholesterol,and low-density lipoprotein cholesterol among patients with T2DM in different NLR groups(P<0.0007).T2DM patients in the highest NLR quartile had a higher prevalence of CKD(P for trend=0.0011).Multivariate logistic regression analysis indicated that a high NLR was an independent risk factor for CKD in T2DM patients even after adjustment for important clinical and pathological parameters(P=0.0001,odds ratio=1.41,95%confidence intervals:1.18-1.68).CONCLUSION An elevated NLR in patients with T2DM is associated with higher prevalence of CKD,suggesting that it could be a marker for the detection and evaluation of diabetic kidney disease.

关键词： Type 2 diabetes mellitus Neutrophil-to-lymphocyte ratio Chronic kidney disease Logistic regression Diabetes mellitus