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Morphology Engineering for Covalent Organic Frameworks (COFs) by Surfactant Mediation and Acid Adjustment

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Chinese Journal of Polymer Science 2022年第4期40卷 338-344页

作者： guang-hui yang Zhe Zhang Cong-Cong Yin Xian-Song Shi Yong Wang State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China

Two-dimensional covalent organic frameworks(COFs)with specific morphologies including nanofibers and nanoplates are highly desired in both nanoscience research and practical *** far,however,morphology engineering for COFs remains challenging because the mechanism underlying the morphology formation and evolution of COFs is not well ***,we propose a strategy of surfactant mediation coupled with acid adjustment to engineer the morphology of aβ-ketoenamine-linked COF,TpPa,during solvothermal *** surfactants function as stabilizers that can encapsulate monomers and prepolymers to create micelles,enabling the formation of fiber-like and plate-like morphologies of TpPa rather than irregularly shaped *** is also found that acetic acid is important in regulating such morphologies,as the amino groups inside the prepolymers can be precisely protonated by acid adjustment,leading to an inhibited ripening process for the creation of specific *** from the synergistic enhancement of surfactant mediation and acid adjustment,TpPa nanofibers with a diameter down to~20 nm along with a length of up to a few microns and TpPa nanoplates with a thickness of~18 nm are *** work sheds light on the mechanism underlying the morphology formation and evolution of TpPa,providing some guidance for exquisite control over the growth of COFs,which is of great significance for their practical applications.

关键词： Covalent organic frameworks(COFs) Morphology engineering Surfactants Nanofibers Nanoplates

Mechanically Reinforced Chitosan/Cellulose Nanocrystals Composites with Good Transparency and Biocompatibility

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Chinese Journal of Polymer Science 2015年第1期33卷 61-69页

作者： Cheng-zhen Geng Xin Hu guang-hui yang Qin Zhang Feng Chen 傅强 College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan University

Chitosan/cellulose nanocrystals（CS/CNCs） composites were prepared with different contents of CNCs. Due to the homogeneous dispersion of CNCs and the strong interfacial interactions resulting from hydrogen bonding between CS chains and CNCs, the transparency of CS is well retained and the overall mechanical properties of CS are significantly improved. Furthermore, because both CS and CNCs are biocompatible materials, cell proliferation test shows that the obtained composites are noncytotoxic and can potentially meet safety requirements of biomedical applications. These advantages pave the way of potential applications of CS in the field of commercial plastics and encourage the use of CS as environmentfriendly material and biomedical material.

关键词： Chitosan Cellulose nanocrystals Reinforcement Cytotoxicity.

Isoflavone genistein protects high glucose-induced human aortic endothelial cell apoptosis through estrogen receptor-mediated pathway

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Journal of Geriatric Cardiology 2008年第2期5卷 86-90页

作者： Wenwen Zhong yang Liu guang yang hui Tian Department of Geriatric Endocrinology Chinese PLA General Hospital Beijing100853China Department of Geriatric EndocrinologyChinese PLA General Hospital Beijing100853China Department of Geriatric EndocrinologyChinese PLA General Hospital Beijing100853China Department of Geriatric EndocrinologyChinese PLA General Hospital Beijing100853China

Objective The aim of this study was to determine if isoflavone genistien has protective effects against high glucose-induced cell apoptosis in human aortic endlthelial cells, and investigate the possible mechanism for this protection. Methods Human aortic endothelial cells subjected to normal (5mmol/L) or high glucose (25mmol/L) were treated with genistein at 0, 50, 100nmol/L. Parallel experiments were performed with 100nM 17b-estradiol, and also in the presence and absence of the pure anti-estrogen ICI-182,780 (100nmol/L). The effects on cell apoptotic DNA fragmentation were determined using cell death ELISA, and the effects on cellular proliferation were determined using tritiated thymidine incorporation assay. Estrogen receptor expression was detected by Taqman quantitative PCR. Results Genistein at 100nmol/L significantly reduced high glucose-induced DNA fragmentation, and reversed cell DNA synthesis inhibition (P <0.001) after 24 hours' incubation. The effect of genistein was completely blocked by ICI-182,780 administration. Estrogen receptor beta, but not alpha was found to be expressed in these cells. Conclusion Isoflavone genistein shows protection against high glucose-induced cell damage through estrogen receptor beta, reducing apoptotic DNA damage and protecting from the inhibition of cell proliferation.

关键词： phytoestrogen endothelial cell high glucose estrogen receptor apoptosis

Size Distribution and Anisotropy of the Minor Phase Droplets in Polypropylene/Ethylene-Octene Copolymer Blends: Effects of Shear and Component Miscibility

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Chinese Journal of Polymer Science 2014年第1期32卷 9-20页

作者： Cheng-zhen Geng Yan-ling Zhu guang-hui yang 傅强 Chao-liang Zhang Ke Wang Tian-nan Zhou College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering Sichuan University State Key Laboratory of Oral Diseases West China Hospital of Stomatology Sichuan University

In this work, polypropylene （PP）/octene-ethylene copolymer （POE） blends were injection-molded using the so- called dynamic packing injection technique, which imposed oscillatory shear on the gradually cooling melt during the packing solidification stage. In this way, the effect of shear on the size distribution and anisotropy of the minor phase droplets could be investigated. Besides, by using two kinds of POE with different octene contents, the effect of component miscibility was also studied. The results show that the droplet size is mainly determined by composition and miscibility, and droplet anisotropy is mainly determined by droplet size and shear. Most importantly, under the same processing condition, droplet anisotropy increases with droplet size, and there seems a linear fit between them, disregarding the miscibility factor. These results may provide guidance for preparing polymer blends with desired properties by tailoring their phase morphologies.

关键词： Shear Miscibility Size distribution Anisotropy Phase morphology.

A numerical study of dynamics in thin hopper flow and granular jet

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Chinese Physics B 2020年第4期29卷 494-504页

作者： Meng-Ke Wang guang-hui yang Sheng Zhang Han-Jie Cai Ping Lin Liang-Wen Chen Lei yang Institute of Modern Physics Chinese Academy of Sciences(CAS)Lanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

The dynamics of granular material discharging from a cuboid but thin hopper,including the hopper flow and granular jet,are investigated via discrete element method(DEM)*** slot width is varied to study its influence on the *** is found the flow in the cuboid hopper has similarity with the flow in two-dimensional(2D)*** the slot width is large,the flowrate is higher than the predicted value from Beverloo’s law and the velocity distribution is not *** granular jet,there is a transition with varying slot *** large slot width,there is a dense core in the jet and the variations of velocities and density are relatively ***,the availability of continuum model is assessed and the results show that the performance with large slot width is better than that with small slot width.

关键词： cuboid hopper granular jet velocity field discrete element method continuum model

Super-high bed sintering for iron ores: inhomogeneous phenomena and its mechanism during mineralizing

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Journal of Iron and Steel Research International 2024年第8期31卷 1850-1860页

作者： hui-bo Liu Liang-ping Xu Xi-duan yang Zhong-lin Dong Qiang Zhong guang-hui Li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina

The inhomogeneous sinter properties in super-high bed sintering have been reported in our previous *** inves-tigate the reasons for the inhomogeneous phenomena,detailed sampling and analysis of mixed material bed and sintered bed in super-high bed sintering plant were *** results indicated that the higher porosity and thinner dendrite of silico-ferrite of calcium and aluminum in the upper layer as well as dense structure and higher secondary hematite content in the lower layer led to the heterogeneities of mechanical strength and reduction properties exceeding 20%and 10%,*** the bed top downward,the basicity of mixed material decreased from 2.13 to 1.68 because the average particle size increased from 2.65 to 4.56 *** and fuels gathered in finer particles(-3 mm)of mixed material,and the-3 mm particles of mixed material generated more liquid phase than+3 mm *** heat input of super-high sintering bed was inhomogeneous due to the heat accumulation effect and unreasonable fuel *** inhomo-geneous sintering heat condition in sintering bed resulted in the different quantities and properties of liquid *** inhomogeneous quantities and properties of liquid phase that were influenced by inhomogeneous distribution of chemical composition,particle size,and heat input led to inhomogeneous mineralizing *** mineralizing condition is the key for homogeneous super-high bed sintering.

关键词： Iron ore Super-high bed sintering Mineralization Material segregation Heat accumulation

Effect of Mn addition on microstructure and mechanical properties of GX40CrNiSi25-12 austenitic heat resistant steel

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China Foundry 2024年第3期21卷 205-212页

作者： Guan-yu Jiang Meng-wu Wu Xiao-guang yang hui Wang Yu-yuan Zhu Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Hubei Longzhong Laboratory Xiangyang 441000HubeiChina Wescast Industries(China)Co. Ltd.Wuhan 430100China

Three types of steels were designed on the basis of GX40CrNiSi25-12 austenitic heat resistant steel by adding different Mn contents(2wt.%,6wt.%,and 12wt.%).Thermodynamic calculation,microstructure characterization and mechanical property tests were conducted to investigate the effect of Mn addition on the microstructure and mechanical properties of the austenitic heat resistant *** show that the matrix structure in all the three types of steels at room temperature is completely *** NbC and M_(23)C_(6)precipitate at grain boundaries of austenite *** the increase of Mn content,the number of carbides increases and their distribution becomes more *** the Mn content increases from 1.99%to 12.06%,the ultimate tensile strength,yield strength and elongation increase by 14.6%,8.0%and 46.3%,*** improvement of the mechanical properties of austenitic steels can be explained by utilizing classic theories of alloy strengthening,including solid solution strengthening,precipitation strengthening,and grain *** increase in alloy strength can be attributed to solid solution strengthening and precipitation strengthening caused by the addition of *** improvement of the plasticity of austenitic steels can be explained from two aspects:grain refinement and homogenization of precipitated phases.

关键词： austenitic heat resistant steel manganese microstructure mechanical properties

Parametric study of the clustering transition in vibration driven granular gas system

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Chinese Physics B 2020年第5期29卷 361-367页

作者： Qi-Lin Wu Mei-Ying Hou Lei yang Wei Wang guang-hui yang Ke-Wei Tao Liang-Wen Chen Sheng Zhang Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Soft Matter Physics Beijing National Laboratory for Condense Matter PhysicsInstitute of PhysicsChinese Academy of SciencesBeijing 100190China

A parametric study of the clustering transition of a vibration-driven granular gas system is performed by *** parameters studied include the global volume fraction of the system,the size of the system,the friction coefficient,and the restitution coefficient among particles and among *** periodic boundary and fixed boundary of sidewalls are also checked in the *** simulation results provide us the necessary“heating”time for the system to reach steady state,and the friction term needed to be included in the“cooling”time.A gas-cluster phase diagram obtained through Kolmogorov-Smirnov(K-S)test analysis using similar experimental parameters is *** influence of the parameters to the transition is then investigated in *** simulation investigation helps us gain understanding which otherwise cannot be obtained by experiment alone,and makes suggestions on the determination of parameters to be chosen in experiments.

关键词： granular gas clustering phase diagram

Effective utilization of dolomitic lead-zinc waste rock by replacing dolomite as flux in iron ore sintering process

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Journal of Iron and Steel Research International 2024年第8期31卷 1861-1872页

作者： Xin Wang Cong-cong yang Jian Pan De-qing Zhu Zheng-qi Guo guang-hui Xia Shi-juan Qu School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Low-Carbon and Hydrogen Metallurgy Research Center Central South UniversityChangsha 410083HunanChina

With increasingly stringent environmental protection policies,cost-effective and value-added treatment of massive lead-zinc waste rock(LZWR)generated from the preconcentration process has attracted substantial attention.A type of dolomitic LZWR with 18 wt.%MgO,27 wt.%CaO,0.29 wt.%Zn and 1.43 wt.%S was used as a replacement flux in the iron ore sintering *** sinter pot tests were carried out based on an industrial ore *** results show that replacing 0%-60%of dolomite with LZWR does not adversely affect the sintering productivity,fuel consumption rate,and the quality of the sinter products,while the Zn and S elements contained in LZWR can be effectively removed with the residual Zn and S contents of the resultant sinter products being less than 0.02 and 0.055 wt.%,***,substituting LZWR for dolomite as a flux inevitably increases the SO_(2) concentration in the sintering flue gas due to its high sulfur *** the processing capacity of the sintering flue gas desulfurization system,the replacement ratio of dolomite can reach 40%,equal to LZWR consumption of 24.3 kg per ton of *** SO_(2) in sintering flue gas can be recovered to produce(NH_(4))_(2)SO_(4) or HSO_(4),while the volatilized Zn collected into the zinc-containing dust can be subsequently recycled by the rotary hearth furnace ***,it is technologically and economically feasible to use the LZWR as a replacement flux in the iron ore sintering process,providing a new way for the safe,large-scale and low-cost treatment of LZWR.

关键词： Lead Zinc waste rock Dolomite Sintering Flue gas Sinter product