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Particuology 2024年第7期90卷 478-492页

作者： Xu Li Yaohui Wang Leifu Li Runye zhang Hailun Ren Wenbin Li Zhongli Tang donghui zhang The Research Center of Chemical Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China The Department of Chemical Engineering Tianjin Renai CollegeTianjin 301636China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Particle-fluid system is one of the most popular systems in chemical processes.Owing to complex interface structure and high-velocity turbulence,the momentum and mass transfer exhibit nonlinear characteristics,which pose a great challenge for further study and application.To solve this problem,computational mass transfer(CMT)emerged and has been proved to be effective in deeply exploring the mass transfer behavior of particle-fluid systems.First,this paper reviews recent gas-solid numerical studies of turbulence issues from empirical to theoretical,then discusses interphase mass transfer rate models and the interfacial interaction force.Second,the present study particularly reviews researches on mass transfer process of fixed and fluidized regime by CMT,providing reliable analysis of turbulent anisotropy diffusivity as well as multiscale structure and presenting theoretical instruction for the industrial optimization of mass transfer processes in chemical engineering.

关键词： Fixed bed Fluidized bed Computational mass transfer Turbulent mass diffusion Multiscale Anisotropy

High adsorption selectivity of activated carbon and carbon molecular sieve boosting CO_(2)/N_(2) and CH_(4)/N_(2) separation

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Chinese Journal of Chemical Engineering 2024年第3期67卷 282-297页

作者： Siang Chen Wenling Wu Zhaoyang Niu Deqi Kong Wenbin Li Zhongli Tang donghui zhang The Research Center of Chemical Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Flue gas and coal bed methane are two important sources of greenhouse gases.Pressure swing adsorption process has a wide range of application in the field of gas separation,and the selection of adsorbent is crucial.In this regard,in order to assess the better adsorbent for separating CO_(2) from flue gas and CH_(4) from coal bed methane,adsorption isotherms of CO_(2),CH_(4) and N_(2) on activated carbon and carbon molecular sieve are measured at 303.15,318.15 and 333.15 K,and up to 250 kPa.The experimental data fit better with Langmuir 2 compared to Langmuir 3 and Langmuir-Freundlich models,and Clausius-Clapeyron equation was used to calculate the isosteric heat.Both the order of the adsorbed amount and the adsorption heat on the two adsorbents are CO_(2)>CH_(4)>N_(2).The adsorption kinetics are calculated by the pseudo-first kinetic model,and the order of adsorption rates on activated carbon is N_(2)-CH_(4)>CO_(2),while on carbon molecular sieve,it is CO_(2)-N_(2)>CH_(4).It is shown that relative molecular mass and adsorption heat are the primary effect on kinetics for activated carbon,while kinetic diameter is the main resistance factor for carbon molecular sieve.Moreover,the adsorption selectivity of CH_(4)/N_(2) and CO_(2)/N_(2) were estimated with the ideal adsorption solution theory,and carbon molecular sieve performed best at 318.15 K for both CO_(2) and CH_(4) separation.The study suggested that activated carbon is a better choice for separating flue gas and carbon molecular sieve can be a strong candidate for separating coal bed methane.

关键词： Activated carbon Carbon molecular sieve Adsorbent evaluation Adsorption equilibrium and kinetics Heat of adsorption Selectivity

Open-vessel Synthesis of Poly-N-methoxyethylglycine

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Chemical Research in Chinese Universities 2024年第1期40卷 153-158页

作者： LIU Guojan MA Ke CHEN Qi zhang donghui LIU Runhui State Key Laboratory of Bioreactor Engineering East China University of Science and TechnologyShanghai200237P.R.China Key Laboratory for Ultrafine Materials of Ministry of Education Frontiers Science Center for Materiobiology and Dynamic ChemistryShanghai Frontiers Science Center of Optogenetic Techniques for Cell MetabolismResearch Center for Biomedical Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai200237P.R.China School of Biotechnology East China University of Science and TechnologyShanghai200237P.R.China

Polypeptoids are widely used in biological applications owing to their diverse functions and proteolytic stability.One type of polypeptoids,poly-N-methoxyethylglycine(P-Nmeg),has been found to possess remarkable hydrophilicity and notable properties in terms of protein,cell,and bacterial antifouling.However,the currently known synthesis methods of P-Nmeg include solid-phase synthesis,which is time-consuming and difficult to scale up,and N-substituted N-carboxyanhydride(NNCA)ring-opening polymerization,whose monomers were difficult to store.In this study,we used the chemical stable Nmeg N-phenoxycarbonyl(NPC)as the monomer,which was obtained without the use of highly toxic reactants,such as phosgene or phosphorus halide,to synthesize P-Nmeg under open-vessel conditions.By adding BnNH_(2) as an initiator at 80℃,we can obtain controllable short chain length P-Nmeg with narrow dispersity.

关键词： Open-vessel Polypeptoid synthesis Poly-N-methoxyethylglycine Stable monomer Narrow dispersity

Lightweight Deep Learning Models for High-Precision Rice Seedling Segmentation from UAV-Based Multispectral Images

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Plant Phenomics 2023年第4期5卷 876-892页

作者： Panli zhang Xiaobo Sun donghui zhang Yuechao Yang Zhenhua Wang College of Engineering Northeast Agricultural UniversityHarbin 150030China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China National Key Laboratory of Remote Sensing Information and Imagery Analyzing Technology Beijing Research Institute of Uranium GeologyBeijing 100029China College of Agriculture Northeast Agricultural UniversityHarbin 150030China

Accurate segmentation and detection of rice seedlings is essential for precision agriculture and high-yield cultivation.However,current methods suffer from high computational complexity and poor robustness to different rice varieties and densities.This article proposes 2 Iightweight neural network architectures,LW-Segnet and LW-Unet,for high-precision rice seedling segmentation.The networks adopt an encoder-decoderstructure with hybrid lightweight convolutions and spatial pyramid dilated convolutions,achieving accurate segmentation while reducing model parameters.Multispectral imagery acquired by unmanned aerial vehicle(UAV)was used to train and test the models covering 3 rice varieties and different planting densities.Experimental results demonstrate that the proposed LW-Segnet and LW-Unet models achieve higher F1-scores and intersection over union values for seedling detection and row segmentation across varieties,indicating improved segmentation accuracy.Furthermore,the models exhibit stable performance when handling different varieties and densities,showing strong robustness.In terms of efficiency,the networks have lower graphics processing unit memory usage,complexity,and parameters but faster inference speeds,reflecting higher computational efficiency.In particular,the fast speed of LW-Unet indicates potential for real-time applications.The study presents lightweight yet effective neural network architectures for agricultural tasks.By handling multiple rice varieties and densities with high accuracy,efficiency,and robustness,the models show promise for use in edge devices and UAVs to assist precision farming and crop management.The findings provide valuable insights into designing lightweight deep learning models to tackle complex agricultural problems.

关键词： seedling union weight

Fracture of films caused by uniaxial tensions:a numerical model

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Applied Mathematics and Mechanics(English Edition) 2023年第12期44卷 2093-2108页

作者： Chenxue JIA Zihao WANG donghui zhang Taihua zhang Xianhong MENG School of Aeronautics and Astronautics University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Space Utilization Technology and Engineering Center for Space UtilizationChinese Academy of SciencesBeijing 100094China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China

Surface cracks are commonly observed in coatings and films.When structures with coatings are subject to stretching,opening mode cracks are likely to form on the surface,which may further lead to other forms of damage,such as interfacial delamination and substrate damage.Possible crack forms include cracks extending towards the interface and channeling across the film.In this paper,a two-dimensional numerical model is proposed to obtain the structural strain energy at arbitrary crack lengths for bilayer structures under uniaxial tension.The energy release rate and structural stress intensity factors can be obtained accordingly,and the effects of geometry and material features on fracture characteristics are investigated,with most crack patterns being confirmed as unstable.The proposed model can also facilitate the analysis of the stress distribution in periodic crack patterns of films.The results from the numerical model are compared with those obtained by the finite element method(FEM),and the accuracy of the theoretical results is demonstrated.

关键词： surface crack numerical model stress intensity factor periodic crack finite element method(FEM)

Design and experiment of high-productivity two-stage vacuum pressure swing adsorption process for carbon capturing from dry flue gas

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Chinese Journal of Chemical Engineering 2022年第3期35卷 378-391页

作者： Xiuxin Yu Bing Liu Yuanhui Shen donghui zhang The Research Center of Chemical Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

A two-stage vacuum pressure swing adsorption(VPSA)process that coupled kinetically controlled and equilibrium controlled separation process with reflux has been investigated for capturing carbon dioxide from dry flue gas(85%N_(2)/15%CO_(2)).In the first enriching stage,carbon molecular sieve(CMS),which shows kinetic selectivity for CO_(2)/N_(2),is adopted as the adsorbent to remove most N_(2)in feed gas,thereby upgrading CO_(2)and significantly reducing the amount for further refinement.The second stage loads zeolite 13X as adsorbent to purify the CO_(2)-rich flow from the first stage for meeting the requirements of National Energy Technology Laboratory.Series of experiments have been conducted for adsorption isotherms measuring and lab-scale experimental validation as well as analysis.The effect of feed composition on the separation performance of the PSA system was studied experimentally and theoretically here.The optimal results achieved 95.1%purity and 92.9%recovery with a high CO_(2)productivity(1.89 mol CO_(2)·h^(-1)·kg^(-1))and an appropriate energy consumption of 1.07 MJ·(kg CO_(2))^(-1).Further analysis has been carried out by simulation for explicating the temperature,pressure,and concentration distribution at cyclic steady state.

关键词： Two-stage VPSA process Binary mixture CO_(2)capture Zeolite 13X Carbon molecular sieve

Integrated vacuum pressure swing adsorption and Rectisol process for CO_(2) capture from underground coal gasification syngas

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Chinese Journal of Chemical Engineering 2023年第5期57卷 265-279页

作者： Jian Wang Yuanhui Shen donghui zhang Zhongli Tang Wenbin Li The Research Center of Chemical Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

An integrated vacuum pressure swing adsorption(VPSA) and Rectisol process is proposed for CO_(2) capture from underground coal gasification(UCG) syngas. A ten-bed VPSA process with silica gel adsorbent is firstly designed to pre-separate and capture 74.57% CO_(2) with a CO_(2) purity of 98.35% from UCG syngas(CH_(4)/CO/CO_(2)/H_(2)/N_(2)= 30.77%/6.15%/44.10%/18.46%/0.52%, mole fraction, from Shaar Lake Mine Field,Xinjiang Province, China) with a feed pressure of 3.5 MPa. Subsequently, the Rectisol process is constructed to furtherly remove and capture the residual CO_(2)remained in light product gas from the VPSA process using cryogenic methanol(233.15 K, 100%(mass)) as absorbent. A final purified gas with CO_(2) concentration lower than 3% and a regenerated CO_(2) product with CO_(2) purity higher than 95% were achieved by using the Rectisol process. Comparisons indicate that the energy consumption is deceased from 2.143 MJ·kg^(-1) of the single Rectisol process to 1.008 MJ·kg^(-1) of the integrated VPSA & Rectisol process, which demonstrated that the deployed VPSA was an energy conservation process for CO_(2) capture from UCG syngas. Additionally, the high-value gas(e.g., CH_(4)) loss can be decreased and the effects of key operating parameters on the process performances were detailed.

关键词： Underground coal gasification Vacuum pressure swing adsorption Rectisol process CO_(2)capture Integrated process

Perspectives of genetic management strategy for inherited cardiovascular diseases in China

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中华医学杂志(英文版) 2024年第8期137卷 959-961页

作者： zhang Yaoyao Zheng Yanjiang Dai Mengyuan Zhou Kaiyu Fu Lijun Guo Yuxuan He Yihua Li Fen Gao Rui zhang donghui Liu Xujie Tian Jie Hua Yimin Li Yifei Qin Lang Shanghai Jiao Tong University Shanghai 200025 Peking University Health Science Center School of Basic Medical Sciences The Institute of Cardiovascular Sciences Key Laboratory of Molecular Cardiovascular Science of Ministry of Education Beijing 100191 Department of Ultrasound Beijing Anzhen Hospital affiliated to Capital Medical University Beijing 100029 Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE State Key Laboratory of Biocatalysis and Enzyme Engineering School of Life Science Hubei University Wuhan Hubei 430062 Shenzhen Key Laboratory of Cardiovascular Disease Fuwai Hospital Chinese Academy of Medical Sciences Shenzhen Guangdong 518052 Ministry of Education Key Laboratory of Child Development and Disorders West China Second University Hospital National Clinical Research Center for Child Health and Disorders (Chongqing) China International Science and Technology Cooperation Base of Child Development and Critical Disorders Children’s Hospital of Chongqing Medical University Chongqing 400014 Sichuan University Chengdu Sichuan 610041 China Department of Cardiology Shanghai Children’s Medical Center School of Medicine

Inherited cardiovascular diseases (CVDs) threaten human health and pose an enormous economic burden worldwide. Genetic alteration is a major risk factor for many CVDs. These disorders are usually controlled by a pair of alleles, affecting offspring according to the Mendelian principle, regardless of isolated primary damage or secondary injury from other syndromes or deficiency. To date, there are hundreds of inherited CVDs. With advances in nextgeneration sequencing (NGS) technologies, rapid and accurate molecular diagnosis of patients with inherited CVDs is clinically practical. Besides, great improvements have been made in recent years, and targeted therapy and assist devices have been used in clinical practice. Yet there is still no totally efficient strategy for dealing with inherited CVDs. Accordingly, there is an urgent need to develop better therapeutic strategies for treating inherited CVDs.

关键词： GENOMIC DNA BASE THERAPY

Improving Ultrasonic Testing by Using Machine Learning Framework Based on Model Interpretation Strategy

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Chinese Journal of Mechanical Engineering 2023年第5期36卷 174-186页

作者： Siqi Shi Shijie Jin donghui zhang Jingyu Liao Dongxin Fu Li Lin NDT&E Laboratory Dalian University of TechnologyDalian 116024China China Nuclear Industry 23 Construction Co. Ltd.Beijing 101300China

Ultrasonic testing(UT)is increasingly combined with machine learning(ML)techniques for intelligently identifying damage.Extracting signifcant features from UT data is essential for efcient defect characterization.Moreover,the hidden physics behind ML is unexplained,reducing the generalization capability and versatility of ML methods in UT.In this paper,a generally applicable ML framework based on the model interpretation strategy is proposed to improve the detection accuracy and computational efciency of UT.Firstly,multi-domain features are extracted from the UT signals with signal processing techniques to construct an initial feature space.Subsequently,a feature selection method based on model interpretable strategy(FS-MIS)is innovatively developed by integrating Shapley additive explanation(SHAP),flter method,embedded method and wrapper method.The most efective ML model and the optimal feature subset with better correlation to the target defects are determined self-adaptively.The proposed framework is validated by identifying and locating side-drilled holes(SDHs)with 0.5λcentral distance and different depths.An ultrasonic array probe is adopted to acquire FMC datasets from several aluminum alloy specimens containing two SDHs by experiments.The optimal feature subset selected by FS-MIS is set as the input of the chosen ML model to train and predict the times of arrival(ToAs)of the scattered waves emitted by adjacent SDHs.The experimental results demonstrate that the relative errors of the predicted ToAs are all below 3.67%with an average error of 0.25%,signifcantly improving the time resolution of UT signals.On this basis,the predicted ToAs are assigned to the corresponding original signals for decoupling overlapped pulse-echoes and reconstructing high-resolution FMC datasets.The imaging resolution is enhanced to 0.5λby implementing the total focusing method(TFM).The relative errors of hole depths and central distance are no more than 0.51%and 3.57%,respectively.Finally,the superior performance of the proposed F

关键词： Ultrasonic testing Machine learning Feature extraction Feature selection Shapley additive explanation

Numerical study on hydrodynamics of gas-solids circulating fluidized bed with L-valve

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颗粒学报:英文版 2023年第6期77卷 37-46页

作者： Hailun Ren Wenbin Li Liang Zeng Kunlei Liu Zhongli Tang donghui zhang Department of Chemical Engineering Tianjin Renai CollegeTianjin301636China School of Chemical Engineering and Technology Tianjin UniversityTianjin300072China Center for Applied Energy Research University of KentuckyLexingtonKY40511United States The Research Center of Chemical Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China

L-valve is often used as a non-mechanical valve for the circulation of solids in gas-solids fluidized bed(GSFB)due to its advantages in simple construction and easy control.The information on solids circu-lation rate as well as the hydrodynamics performance of the CFB with L-valve is of great importance for its better control and design.This paper proposes a Eulerian-Eulerian approach based numerical model integrating the computational fluid dynamics(CFD)with turbulent model,the kinetic theory of granular flow(KTGF)and the drag model,thus the solids circulation rate and the local phase velocity as well as solids volume fraction can be predicted simultaneously.With this model,the hydrodynamics perfor-mance of the full loop GSCFB with a L-valve is analyzed in detail.It is found that the drag model affects the simulation significantly and the(energy minimization multiscale)EMMS method shows good per-formance in the full-loop simulation of GSCFB.

关键词： Gas-solids circulating fluidizedbed L-valve Computational fluid dynamics Drag model Full-loop simulation