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Effect of swirling addition on the liquid mixing performance in a T-jets mixer

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Chinese Journal of Chemical Engineering 2022年第10期50卷 108-116页

作者： Chunhui Li Bin Wu Junjie zhang peicheng Luo School of Chemistry and Chemical Engineering Southeast UniversityNanjing 211189China Hubei Sanjiang Aerospace Jianghe Chemical Technology Co. LtdYichang 444200China

Swirling addition to the stream is beneficial for the fluid mixing.This work aims to study the mixing process intensification in a conventional T-jets mixer by the swirling addition.After experimental verification by the planar laser-induced fluorescence technique,large eddy simulation with the dynamic kinetic energy sub-grid stress model is used to predict how the swirling strength(in terms of swirling number,S_(w))and swirling directions affect the mixing performance,e.***.the tracer concentration distribution,mixing time,and turbulent characteristics in the T-jets mixers,Predictions show that the swirling strength is the key factor affecting the mixing efficiency of the process.The overall mixing time,τ_(90),can be significantly reduced by increasing S_(w).Vortex analysis shows that more turbulent eddies appear in the collision zone and the turbulent kinetic energy dissipation rate increases obviously with the swirling addition.When S_(w) is kept constant,the mixing process can be accelerated and intensified by adding swirling to only one stream,to both streams with the opposite swirling directions,or to both streams with the same swirling directions.Amplification of the mixing process by enlarging the mixer size or increasing the flow rates is also optimized.Thus,this work provides a new strategy to improve the mixing performance of the traditional T-jets mixers by the swirling addition.

关键词： Mixing T-jets mixer Swirling Computational fluiddynamics(CFD) Large eddysimulation

Bioactive thionic compounds and aromatic glycosides from Ligusticum chuanxiong

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Acta Pharmaceutica Sinica B 2018年第5期8卷 818-824页

作者： Xu zhang Bing Han Ziming Feng Jianshuang Jiang Yanan Yang Peicheng Zhang State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia Medica Peking Union Medical College and Chinese Academy of Medical Sciences

Three new thionic compounds,(S)-2-(2-carboxyl-2-hydroxyethylthio)-ferulic acid(1),(E)-2-methoxy-4-(3-(methylsulfonyl)prop-1-en-1-yl)phenol(2), and thiosenkyunolide C(3), together with two new aromatic glycosides(4 and 5) were isolated from the rhizome of Ligusticum chuanxiong Hort. Two known compounds(6 and 7) were also obtained. Their structures were elucidated based on extensive spectroscopic data(UV, IR, 1D and 2D NMR, and HR-ESI-MS). Furthermore the absolute configurations were established by comparison of their calculated and experimental circular dichroism spectra and by a dimolybdenum tetraacetate [Mo_2(AcO)_4]-induced circular dichroism procedure. All compounds were evaluated against lipopolysaccharide(LPS)-induced NO production in BV2 cells, and compounds 4 and 5 showed strong inhibitory activities with IC_(50) values of 2.03 and 3.09 μmol/L, respectively(positive control curcumin, IC_(50)=6.17 μmol/L). In addition, compound 1 showed weak proteintyrosine phosphatase-1 B(PTP1B) inhibitory activity.

关键词： Ligusticum chuanxiong Hort. Thionic compounds Aromatic glycosides Anti-inflammatory Natural products

ST-LaneNet: Lane Line Detection Method Based on Swin Transformer and LaneNet

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 130-145页

作者： Yufeng Du Rongyun zhang peicheng Shi Linfeng Zhao Bin zhang Yaming Liu School of Mechanical Engineering Anhui Polytechnic UniversityWuhu 241000China Automotive New Technology Anhui Engineering and Technology Research Center Anhui Polytechnic UniversityWuhu 241000China School of Automotive and Transportation Engineering Hefei University of TechnologyHefei 230009China

The advancement of autonomous driving heavily relies on the ability to accurate lane lines detection.As deep learning and computer vision technologies evolve,a variety of deep learning-based methods for lane line detection have been proposed by researchers in the field.However,owing to the simple appearance of lane lines and the lack of distinctive features,it is easy for other objects with similar local appearances to interfere with the process of detecting lane lines.The precision of lane line detection is limited by the unpredictable quantity and diversity of lane lines.To address the aforementioned challenges,we propose a novel deep learning approach for lane line detection.This method leverages the Swin Transformer in conjunction with LaneNet(called ST-LaneNet).The experience results showed that the true positive detection rate can reach 97.53%for easy lanes and 96.83%for difficult lanes(such as scenes with severe occlusion and extreme lighting conditions),which can better accomplish the objective of detecting lane lines.In 1000 detection samples,the average detection accuracy can reach 97.83%,the average inference time per image can reach 17.8 ms,and the average number of frames per second can reach 64.8 Hz.The programming scripts and associated models for this project can be accessed openly at the following GitHub repository:https://***/Duane 711/Lane-line-detec tion-ST-LaneNet.

关键词： Autonomous driving Lane line detection Deep learning Swin transformer

Alopecuroidines A-C, three matrine-derived alkaloids from the seeds of Sophora alopecuroides

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Chinese Chemical Letters 2021年第12期32卷 4058-4062页

作者： Xiang Yuan Zhenyuan Li Ziming Feng Jianshuang Jiang Yanan Yang Peicheng Zhang State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

Three matrine-derived alkaloids, alopecuroidine A(1), alopecuroidine B(2 a) and alopecuroidine C(2 b)were isolated from the seeds of Sophora alopecuroides. Their structures were elucidated by extensive spectroscopic analyses and X-ray diffraction. Three compounds possess an unprecedented rearranged fused7/6/5/6 tetracyclic skeleton with a diazacycloheptane structure. Their plausible biosynthetic pathway was also proposed. The anti-proliferative activities of compounds 1 and 2 a were examined by the MTT assay.Compound 1 inhibited the viability of human lung cancer A549 cells, having a half maximal inhibitory concentration(IC50) of 7.58 ± 2.47 μmol/L at 72 h. The flow cytometric analysis suggested that 1 inhibited A549 cell growth by inducing apoptosis and cell-cycle arrest. Additionally, 1 induced the loss of mitochondrial membrane potential, elevated intracellular reactive oxygen species, increased the Bax/Bcl-2 ratio, stimulated cleaved-caspase-3 and P53 protein levels, and suppressed the pro-caspase-3 level. Thus,1 appeared to induce A549 cells apoptosis through a mitochondria-mediated apoptotic pathway.

关键词： Alkaloids Sophora alopecuroides X-ray diffraction Anti-proliferative Apoptosis

1,2-Dibromoethane and KI mediated α-acyloxylation of ketones with carboxylic acids

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Chinese Chemical Letters 2020年第3期31卷 711-714页

作者： Xujie Wang Gangsheng Li Yanan Yang Jianshuang Jiang Ziming Feng Peicheng Zhang State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

The 1,2-dibromoethane-and Kl-mediatedα-acyloxylation of ketones is reported in moderate to good yield without the use of transition metals and strong oxidants.Various acids are well tolerated with wide functional group compatibility.An 1,2-dibromoethane-and Kl-catalysed reaction mechanism is proposed based on the results of control experiments.

关键词： 1,2-Dibromoethane KI α-Acyloxylation Ketones Carboxylic acids

Recent progress of tree frog toe pads inspired wet adhesive materials

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Biosurface and Biotribology 2022年第4期8卷 279-289页

作者： Yikai zhang Xizi Wan Xuetao Xu peicheng Teng Shutao Wang Key Laboratory of Bio‐inspired Materials and Interface Science Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina

Wet adhesion has widespread applications in the fields of wearable electronics,medical devices and intelligent robots.In nature,many organisms have evolved with unique wet adhesion properties to adapt to complex habitats and climb in wet environments without falling.Tree frogs,as crawling masters in tropical rain forests,are representative of wet adhesion and give novel inspirations to design artificial wet adhesive materials by mimicking their specialised hexagonal structures and/or mucus composition.In this review,we first overview the research progress of tree frog toe pads from the perspective of toe pad structure and adhesion mechanism.Then,wet adhesive materials inspired by tree frog toe pads are systematically summarised from(i)the typical polymers,(ii)the preparation approaches,(iii)the adhesion test methods and(iv)the typical artificial adhesion surfaces.Third,various applications of bioinspired wet adhesive surfaces are highlighted.Finally,we present future challenges and opportunities to develop tree frog-inspired wet adhesive materials.

关键词： wear artificial hexagonal

Nine compounds from the root bark of Lycium chinense and their anti-inflammatory activities

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Acta Pharmaceutica Sinica B 2017年第4期7卷 491-495页

作者： Yanan Yang Yawen An Wei Wang Ning Du Jinghua zhang Ziming Feng Jianshuang Jiang Peicheng Zhang State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China Beijing Centre for Physical and Chemical Analysis Beijing 100089China

Two new compounds, named lyciumlignan D(1) and lyciumphenyl propanoid A(2), along with seven known compounds, were isolated from the root bark of Lycium chinense. Their structures were elucidated using spectroscopic data(UV, IR, HR-ESI-MS, 1D and 2D NMR, CD), as well as by comparison with those of the literature. Compounds 3–9 were isolated from this genus for the first time. In the in vitro assay, compounds 3, 6, and 7 exhibited stronger anti-inflammatory effects than the positive control curcumin at a concentration of 10 μmol/L.

关键词： Lycium chinense Lyciumlignan D Lyciumphenyl propanoid A 组织说明反煽动性的效果

Temporal Trends of Clinical Characteristics and Treatments in People Living with HIV at the Initiation of Antiretroviral Therapy — Beijing Municipality, China, 2010–2020

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China CDC weekly 2023年第6期5卷 131-136,I0013页

作者： Jinjuan zhang Mengge Zhou peicheng Wang Duoduo Wang Yuanqi Mi Jufen Liu Feng Cheng Institute of Reproductive and Child Health/National Health Commission Key Laboratory of Reproductive Health Peking UniversityBeijing MunicipalityChina Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijing MunicipalityChina Department of Epidemiology and Biostatistics Institute of Basic Medical Sciences Chinese Academy of Medical SciencesSchool of Basic Medicine Peking Union Medical CollegeBeijing MunicipalityChina School of Medicine Tsinghua UniversityBeijing MunicipalityChina Department of Epidemiology Bloomberg School of Public HealthJohns Hopkins UniversityBaltimoreUSA

Summary What is already known about this topic?Antiretroviral therapy(ART)eligibility criteria and treatment regimens were updated in national guidelines.However,whether treatment was timely and followed guidelines wa... 详细信息

关键词： Therapy assessed Clinical

Simulation and verification analysis of the ride comfort of an in-wheel motor-driven electric vehicle based on a combination of ADAMS and MATLAB

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International Journal of Modeling, Simulation, and Scientific Computing 2022年第1期13卷 99-116页

作者： peicheng Shi Qi Zhao Kefei Wang Rongyun zhang Ping Xiao Anhui Engineering Technology Research Center of Automotive New Technique Anhui Polytechnic University Wuhu 241000 P.R.China Chery Automobile Co. Ltd.Wuhu 241009P.R.China

To study the ride comfort of wheel-hub-driven electric vehicles,a simulation and verifi-cation method based on a combination of ADAMS and MATLAB modeling is proposed.First,a multibody dynamic simulation model of an in-wheel motor-driven electric vehi-cle is established using ADAMS/Car.Then,the pavement excitation and electromag-netic force analytical equations are provided based on the specific operating conditions of the vehicle and the in-wheel motor to analyze the impact of the electromagnetic force fluctuation from an unsprung mass increase and motor air gap unevenness on vehicle ride comfort after the introduction of an in-wheel motor.Next,the vibration model and the motion differential equation of the body–wheel dual-mass system of an in-wheel motor-driven electric vehicle are established.The influence of the in-wheel motor on the vibration response index of the dual-mass system is analyzed by using MATLAB/Simulink software.The variation in the vehicle vibration performance index with/without the motor electromagnetic force excitation factor is analyzed and com-pared with the ADAMS multibody dynamics analysis results.The results show that the method based on a combination of ADAMS and MATLAB modeling can forecast the ride comfort of an in-wheel motor-driven electric vehicle,reducing the cost of physical prototype experiments.

关键词： In-wheel motor electric vehicle ride comfort ADAMS/Car MAT-LAB/Simulink