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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 nanotubes.To improve the production volume and product quality of carbon nanotubes,the study of fluidized-bed-diameter scaling is important.Three 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 investigated.Time-series and wavelet analysis methods were used to analyze the pressure-fluctuation signals inside the fluidized beds.Results 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 diameter.The powder-bridging phenomenon of carbon nanotube clusters in a 100-mm-diameter fluidized bed was related to the special microstructure of carbon nanotube clusters.The frequency of pressure fluctuations in the bed decreased nonlinearly with increasing bed diameter.This 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

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Fluidization dynamic characteristics of carbon nanotube particles in a tapered fluidized bed

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Chinese Journal of Chemical Engineering 2022年第4期35卷 321-331页

作者： wenjuan bai Dianming Chu Yan He Shandong Engineering Laboratory for Preparation and Application of High-performance Carbon-Materials College of Electromechanical EngineeringQingdao University of Science and TechnologyShandong 266061China

In this work,a tapered fluidized bed(TFB)without a distributor for fluidizing carbon nanotube(CNT)was applied for improving the dead zone,blockage,and fracture of distributor,which occurred in actual production.Experiments were performed under different superficial gas velocities,static bed heights,CNT agglomerate size,and positions of pressure probe.To obtain multi-perspective and multi-scale understanding of fluidization dynamics of gas–CNT flow in the TFB without a distributor,the standard deviation,skewness,kurtosis,wavelet decompositions and homogeneous index analysis methods were adopted.Some noticeable phenomena were observed.Particle movements including inter-particle,gas–particle and particle–wall dominate dynamic characteristics.The amplitudes of pressure fluctuations of coarse agglomerated multi-walled CNT were more sensitive to the gas velocity than that of fine agglomerated multi-walled CNT.The sensitively of energy contribution of the meso-and macrostructures was that the sensitivity of the measured position was less than the sensitivity of the energy contribution by the changes of particle size,and the sensitivity of the energy contribution by the changes of particle size was less than the energy contribution by the changes of gas velocity.The fluidization quality of coarse agglomerated multi-walled CNT was better than that of fine agglomerated multi-walled CNT,which was verified by the skewness and wavelet analysis.

关键词： Tapered fluidized bed Gas–CNT flow Pressure fluctuation Wavelet Homogeneous index Carbon nanotubes

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The motion mechanism and characteristic of bubble in a pseudo-2D tapered fluidized bed

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Chinese Journal of Chemical Engineering 2022年第6期35卷 255-270页

作者： wenjuan bai Dianming Chu Kuanxin Tang Lei Geng Yan Li Yan He Shandong Engineering Laboratory for Preparation and Application of High-performance Carbon-Materials College of Electromechanical EngineeringQingdao University of Science and TechnologyShandong 266061China ShangDong Dazhan Nano Materials Co. LtdShandong 256220China

The different carbon nanotube(CNT)particles(^(@)A and^(@)V)were bed materials in the pseudo-2D tapered fluidized bed(TFB)with/without a distributor.A detailed investigation of the motion mechanism of bubbles was carried out.The high-speed photography and image analysis techniques were used to study bubble characteristic and mixing behavior in the tapered angle of TFB without a distributor.The fractal analysis method was used to analyze the degree of particles movement.Results showed that an S-shaped motion trajectory of bubbles was captured in the bed of^(@)V particles.The population of observational bubbles in the bed of^(@)V particles was more than that of^(@)A particles,and the bubble size was smaller in the bed of^(@)V particles than that of^(@)A particles.The motion mechanism of bubbles had been shown to be related to bed materials and initial bed height in terms of analysis and comparison of bubble diameter,bubble aspect ratio and bubble shape factor.Importantly,compared to the TFB with a distributor,the TFB without a distributor had been proved to be beneficial to the CNT fluidization according to the study of bubble characteristic and the degree of the particle movement.Additionally,it was found that the mixing behavior of^(@)V particles was better than^(@)A particles in the tapered angle of TFB without a distributor.

关键词： Tapered fluidized bed Carbon nanotube Bubble characteristic Image processing technique Fractal analysis

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A novel reporter mouse line for studying alveolar macrophages

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Science China(Life Sciences) 2023年第11期66卷 2527-2542页

作者： Xiaoyun Zhao Liang Li Hongxiang Sun Xiaoli Jiang wenjuan bai Ningbo Wu Jing Wang Bing Su Shanghai Institute of Immunology Department of Immunology and Microbiologyand the Ministry of Education Key Laboratory of Cell Death and DifferentiationShanghai Jiao Tong University School of MedicineShanghai 200025China Center for Immune-Related Diseases at Shanghai Institute of Immunology Department of GastroenterologyRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China Shanghai Jiao Tong University School of Medicine—Yale Institute for Immune Metabolism Shanghai Jiao Tong University School of MedicineShanghai 200025China Key Laboratory of Molecular Radiation Oncology of Hunan Province Xiangya HospitalCentral South UniversityChangsha 410008China

Alveolar macrophages(AMs)are self-maintained immune cells that play vital roles in lung homeostasis and immunity.Although reporter mice and culture systems have been established for studying macrophages,an accurate and specific reporter line for alveolar macrophage study is still not available.Here we reported a novel Rspo1-tdTomato gene reporter mouse line that could specifically label mouse AMs in a cell-intrinsic manner.Using this reporter system,we visualized the dynamics of alveolar macrophages intravitally under steady state and characterized the alveolar macrophage differentiation under in vitro condition.By performing ATAC-seq,we found that insertion of the tdTomato cassette in the Rspo1 locus increased the accessibility of a PPARE motif within the Rspo1 locus and revealed a potential regulation by key transcription factor PPAR-γfor alveolar macrophage differentiation in vitro and in vivo.Consistently,perturbation of PPAR-γby its agonist rosiglitazone or inhibitor GW9662 resulted in corresponding alteration of tdTomato expression in alveolar macrophages together with the transcription of PPAR-γdownstream target genes.Furthermore,global transcriptomic analyses of AMs from the wild type mice and the Rspo1-tdTomato mice showed comparable gene expression profiles,especially those AM-specific genes,confirming that the insertion of the tdTomato cassette in the Rspo1 locus does not impact the cell identity and biological function of AMs under normal condition.Taken together,our study provides an alternative tool for in vivo and in vitro labeling of alveolar macrophages with high specificity which could also be utilized as an indicator of PPAR-γactivity for future development of PPAR-γspecific targeting drugs.

关键词： alveolar macrophage gene reporter mice PPAR-γ R-spondin 1 ATAC-seq

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房颤射频消融患者的聚类分析及消融成功率评价

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四川大学学报（医学版） 2024年第3期55卷 687-692页

作者：黄凤誉钟玥张然白文娟李娅姣龚深圳陈石朱亭西陈一龙饶莉四川大学华西医院心内科成都610041 四川大学华西医院生物医学大数据中心成都610041

目的房颤是一组异质性较高的疾病,本研究拟通过聚类分析探讨房颤患者的不同亚型,并进一步评估不同的射频消融术式在不同房颤亚型中的成功率。方法本研究回顾性纳入1 102例接受房颤射频消融的患者,基于59项基线变量进行层次聚类分析,... 详细信息

目的房颤是一组异质性较高的疾病,本研究拟通过聚类分析探讨房颤患者的不同亚型,并进一步评估不同的射频消融术式在不同房颤亚型中的成功率。方法本研究回顾性纳入1 102例接受房颤射频消融的患者,基于59项基线变量进行层次聚类分析,并在聚类分析产生的房颤亚型间比较射频消融术后窦性心律转复的成功率。结果基于层次聚类分析产生了5类房颤患者亚型:(1)较年轻房颤患者组(n=404);(2)较年长且合并慢病组(n=438);(3)窦房结功能障碍发生率较高组(n=160);(4)合并心衰组(n=80);(5)缺血性心肌病组(n=20)。在术后6个月随访时,亚型1(较年轻组)的消融成功率最高(81.2%),但亚型5(缺血性心肌病组)的消融成功率最低(65.0%)(P<0.05)。就早期消融成功率而言,与肺静脉隔离(pulmonary veins isolation, PVI)基础上复合异位病灶消融的广泛消融策略相比,仅在亚型2(较年长且合并慢病组)的患者中,单纯PVI与较高的消融成功率相关[79.6%vs. 66.5%;比值比(odds ratio, OR)=1.97,95%置信区间(confidence interval,CI):1.28~3.03]。结论通过聚类分析产生的房颤亚型之间存在接受射频消融治疗效果的差异,聚类分析产生的亚组分型可为患者的个体化治疗提供一定的参考依据。

关键词：导管消融术心房颤动聚类分析

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Benefit of aerosol reduction to winter wheat during China's clean air action:A case study of Henan Province

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Journal of Environmental Sciences 2024年第7期141卷 90-101页

作者： Yang bai Pengfei Zhao Xueyang Chen Lijun Wang wenjuan Chang Jianzhong Guo Jiayao Wang College of Geography and Environmental Science Henan UniversityKaifeng 475004China Henan Industrial Technology Academy of Spatio-Temporal Big Data Henan UniversityZhengzhou 475000China Henan Technology Innovation Center of Spatio-Temporal Big Data Henan UniversityZhengzhou 450046China Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions(Henan University) Ministry of EducationKaifeng 475000China

A strongly declining aerosol radiative effect has been observed in China since 2013 after implementing the clean air action,yet its impact on wheat(Triticum aestivum L.)production remains unclear.We use satellite measures and a biophysical crop model to assess the impact of aerosol-induced radiative perturbations on winter wheat production in the agricultural belt of Henan province from 2013 to 2018.After calibrating parameters with the extended Fourier Amplitude Sensitivity Test(EFAST)and the generalized likelihood uncertainty estimation(GLUE)method,the DSSAT CERES-Wheat model was able to simulate crop biomass and yield more accurately.We found that the aerosol negatively impacted wheat biomass by 21.87%and yield by 22.48%from 2006 to 2018,and the biomass effects from planting to anthesis were more significant compared to anthesis to maturity.Due to the strict clean air action,under all-sky conditions,the surface solar shortwave radiation(SSR)in 2018 increased by about 7.08%over 2006-2013 during the wheat growing seasons.As a result of the improvement of crop photosynthesis,winter wheat biomass and yield increased by an average of 5.46%and 2.9%,respectively.Our findings show that crop carbon uptake and yield will benefit from the clean air action in China,helping to ensure national food and health security.

关键词： Haze pollution Clean air action Aerosol-induced radiative perturbation Wheat production DSSAT model

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A DNA tetrahedron-based ferroptosis-suppressing nanoparticle: superior delivery of curcumin and alleviation of diabetic osteoporosis

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Bone Research 2024年第1期12卷 227-239页

作者： Yong Li Zhengwen Cai wenjuan Ma Long bai En Luo Yunfeng Lin State Key Laboratory of Oral Diseases&National Center for Stomatology&National Clinical Research Center for Oral Diseases West China Hospital of StomatologySichuan UniversityChengduSichuan 610041PR China Department of Oral and Maxillofacial Surgery Affiliated Stomatological HospitalSouthwest Medical UniversityLuzhouSichuan 646000PR China Sichuan Provincial Engineering Research Center of Oral Biomaterials ChengduSichuan 610041China

Diabetic osteoporosis(DOP)is a significant complication that poses continuous threat to the bone health of patients with diabetes;however,currently,there are no effective treatment strategies.In patients with diabetes,the increased levels of ferroptosis affect the osteogenic commitment and differentiation of bone mesenchymal stem cells(BMSCs),leading to significant skeletal changes.To address this issue,we aimed to target ferroptosis and propose a novel therapeutic approach for the treatment of DOP.We synthesized ferroptosis-suppressing nanoparticles,which could deliver curcumin,a natural compound,to the bone marrow using tetrahedral framework nucleic acid(tFNA).This delivery system demonstrated excellent curcumin bioavailability and stability,as well as synergistic properties with tFNA.Both in vitro and in vivo experiments revealed that nanoparticles could enhance mitochondrial function by activating the nuclear factor E2-related factor 2(NRF2)/glutathione peroxidase 4(GPX4)pathway,inhibiting ferroptosis,promoting the osteogenic differentiation of BMSCs in the diabetic microenvironment,reducing trabecular loss,and increasing bone formation.These findings suggest that curcumin-containing DNA tetrahedron-based ferroptosissuppressing nanoparticles have a promising potential for the treatment of DOP and other ferroptosis-related diseases.

关键词： curcumin osteoporosis diabetic

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草酸二甲酯中硝酸根的检测

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山东化工 2024年第3期53卷 161-163,168页

作者：白文娟马小剑何建华王法庭王香回国家能源集团榆林化工有限公司陕西榆林719000

离子色谱分析技术是在近年来发展得比较快的一项分析方法,它具有灵敏度高、分析速度快、选择性好、试样用量少、能实现同时测定多组分和不同价态化合物的离子、易实现自动化等优点。离子色谱主要被用来研究测定无机阴阳离子,本文主要建... 详细信息

离子色谱分析技术是在近年来发展得比较快的一项分析方法,它具有灵敏度高、分析速度快、选择性好、试样用量少、能实现同时测定多组分和不同价态化合物的离子、易实现自动化等优点。离子色谱主要被用来研究测定无机阴阳离子,本文主要建立了离子色谱测定草酸二甲酯中硝酸根含量的分析方法。该方法通过水解和氧化草酸二甲酯样品的预处理手段,消除样品复杂基体和样品水解生成草酸根对硝酸根测定的干扰,选用赛默飞AG23+AS23阴离子色谱柱,以4.5 mmol Na_(2)CO_(3)+0.8 mmol NaHCO3混合溶液作为淋洗液,离子色谱峰不仅分离良好,且16 min即可完成分析。该方法在硝酸根质量浓度6.25~100 mg/L范围内线性方程为y=0.1036x-0.2896,R2=0.9991,测得实际样品硝酸根含量相对标准偏差RSD为1.5278%(n=4),完全满足化工生产中间控制分析的及时性和准确性要求。

关键词：草酸二甲酯硝酸根离子色谱准确度精密度

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基于区块链的教学多视点视频生成和管理系统设计

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无线互联科技 2024年第6期21卷 75-78页

作者：王飞杨秉杰白文娟朱登勇陈红杰郑州大学计算机与人工智能学院河南郑州450001 国家计算机网络与信息安全管理中心河南分中心河南郑州450001 河南省高速公路联网监控收费通信服务有限公司河南郑州450001 郑州大学教务处河南郑州450001

随着3D显示快速融入人们生活,多视点视频作为其重要的支撑技术得到广泛关注。多视点视频是一种能够满足用户全方位、多角度观看视频的视频采集技术,目前多视点视频主要存放在集中存储的磁盘阵列,存在数据篡改或替换的隐患,不适合教育等... 详细信息

随着3D显示快速融入人们生活,多视点视频作为其重要的支撑技术得到广泛关注。多视点视频是一种能够满足用户全方位、多角度观看视频的视频采集技术,目前多视点视频主要存放在集中存储的磁盘阵列,存在数据篡改或替换的隐患,不适合教育等保密要求较高的场景开展应用,因此,文章基于区块链技术进行多视点视频生成和管理系统设计,能够在有效满足视频实时传输的基础上确保视频访问和管理的安全性。

关键词：区块链多视点视频管理系统

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Preparation and characterization of porous titanium using space-holder technique

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Rare Metals 2009年第4期28卷 338-342页

作者： NIU wenjuan bai Chenguang QIU Guibao WANG Qiang WEN Liangying CHEN Dengfu DONG Lingyan College of Materials Science and Engineering Chongqing University Chongqing 400044 China

Titanium-based porous materials can be used in structural applications and medical implants because of their excellent mechanical properties at elevated temperatures, good corrosion resistance and wonderful biocompatibility. However, most of the methods used to produce the porous metal can only give limited porosity and uncontrollable pore morphologies. In the present study, a newly developed method of powder metallurgy using the space-holder technique was used to fabricate porous titanium with controllable porosity. The morphological features and mechanical properties of the products were fully investigated. The results show that the porosity is in the range of 55%-75%, and the mean pore size, with an average sphericity of -0.72, is 600 μm. The plateau stresses vary between 10 MPa and 35 MPa. As predicted by the Gibson-Ashby model, the plateau stress decreases with increasing porosity.

关键词： powder metallurgy porous titanium space-holder pore morphology mechanical properties

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