Synthesis of full concentration gradient cathode studied by high energy X-ray diffraction

Li, Yan,Xu, Rui,Ren, Yang,Lu, Jun,Wu, Huiming,Wang, Lifen,Miller, Dean J.,Sun, Yang-Kook,Amine, Khalil,Chen, Zonghai Elsevier 2016 Nano energy Vol.19 No.-

<P><B>Abstract</B></P> <P>Nickel-rich metal oxides have been widely pursued as promising cathode materials for high energy-density lithium-ion batteries. Nickel-rich lithium transition metal oxides can deliver a high specific capacity during cycling, but can react with non-aqueous electrolytes. In this work, we have employed a full concentration gradient (FCG) design to provide a nickel-rich core to deliver high capacity and a manganese-rich outer layer to provide enhanced stability and cycle life. <I>In situ</I> high-energy X-ray diffraction was utilized to study the structural evolution of oxides during the solid-state synthesis of FCG lithium transition metal oxide with a nominal composition of LiNi<SUB>0.6</SUB>Mn<SUB>0.2</SUB>Co<SUB>0.2</SUB>O<SUB>2</SUB>. We found that both the pre-heating step and the sintering temperature were critical in controlling phase separation of the transition metal oxides and minimizing the content of Li<SUB>2</SUB>CO<SUB>3</SUB> and NiO, both of which deteriorate the electrochemical performance of the final material. The insights revealed in this work can also be utilized for the design of other nickel-rich high energy-density cathode materials.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Solid-state synthesis of FCG cathode is investigated by <I>in situ</I> XRD. </LI> <LI> Covariance analysis and Rietveld refinement are used to analyze the HEXRD data. </LI> <LI> Synthetic optimization of FCG cathode with excellent electrochemical performance. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Benefit from the covariance analysis and Rietveld refinement of <I>in situ</I> HEXRD data during the solid state synthesis, we can optimized the solid state synthesis conditions in a short time. And the full concentration gradient cathode composites (nickel-rich core and manganese-rich outer layer) with excellent electrochemical performance are obtained.</P> <P>[DISPLAY OMISSION]</P>

Aprotic and Aqueous Li–O₂ Batteries

Lu, Jun,Li, Li,Park, Jin-Bum,Sun, Yang-Kook,Wu, Feng,Amine, Khalil American Chemical Society 2014 Chemical reviews Vol.114 No.11

<P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/chreay/2014/chreay.2014.114.issue-11/cr400573b/production/images/medium/cr-2013-00573b_0033.gif'></P>

Coal dust exposure induces proliferation and migration of human bronchial epithelial cells

Li Amin,Zhang Yinci,Wang Ruikai,Xu Ruyue,Ma Yongfang,Song Li,Cao Weiya,Xiaolong Tang 대한독성 유전단백체 학회 2023 Molecular & cellular toxicology Vol.19 No.2

Background Coal dust exposure has caused a variety of lung diseases. In addition to genotoxicity and cytotoxicity, other biological changes caused by coal dust (CD) exposure need further study. Objective To observe the cellular transformation eff ects of CD exposure and explore its underlying molecular mechanism, human bronchial epithelial cells (BEAS-2B) were cultured with continuous CD exposure. Methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay, colony formation assay, wound healing assay, next-generation sequencing (NGS) and western blotting were performed to observe the cell proliferation, migration, genomic transcription and pathological signaling pathways. Results We demonstrated that BEAS-2B cells with long-term chronic CD exposure show accelerated proliferation rate and enhanced migration ability, and have altered gene expression profi les and aberrant activation of EGFR/Raf/ERK and PI3K/ AKT/mTOR pathways. Conclusions The results indicate that chronic CD exposure could induce abnormal proliferation and migration of BEAS-2B cells, lead to the transformation potential of human bronchial epithelial cells.

The Investment Always Will Get Gains? Advertising Expenditure and Enterprise Performance Based on Corporate Life Cycle

Li, Liang,Amine, Bouirig,Pang, Yuxin,Jiang, Minxing Kyung Hee University Management Research Institute 2022 Asia pacific journal of business review Vol.6 No.2

Based on the concept of advertising expenditure, manufacturing firm performance, and enterprise life cycle, this research conducts the listed Chinese manufacturing listed in 2016-2018 as the research sampling and divides these listed companies into three periods: growth, maturity, and decline. Next, this paper conducts empirical research from three aspects: advertising expenditure or investment and manufacturing firm performance, lag effect of advertising expenditure, and outcome effect and lag effect of advertising investment. It is found that in different stages of manufacturing enterprises, different advertising expenditures will have different impacts on the performance of manufacturing enterprises. In the growth stage, the advertising investment of manufacturing enterprises will significantly affect the performance results of the current period, and there will be the long-term lag effect. In contrast, the mature stage of enterprises' advertising investment has a shorter period of lag effect, while in the recession stage, the mature stage of manufacturing enterprises' advertising investment will have a shorter period of lag effect. The empirical results are not significant. This study provides a reference for manufacturing enterprises in different stages in the decision-making of advertising investment.

Advancing real-time hybrid simulation for coupled nonlinear soil-isolator-structure system

Hongwei Li,Amin Maghareh,Johnny W.C. Uribe,Herta Montoya,Shirley J. Dyke,Zhao-Dong Xu 국제구조공학회 2021 Smart Structures and Systems, An International Jou Vol.28 No.1

Experiments involving soil-structure interaction are often constrained by the capacity and other limitations of the shake table. Additionally, it is usually necessary to consider different types of soil in experiments. Real-time hybrid simulation (RTHS) offers an alternative method to conduct such tests. RTHS is a cyber-physical testing technique that splits the dynamic system under investigation into numerical and physical components, and then realistically couples those components in a single test. A limited number of previous studies involving soil-structure interaction have been conducted using RTHS, with a focus on linear models and systems. The presence of isolators was not considered in these studies to the authors’ best knowledge. Herein, we aim to advance the understanding of the RTHS method by developing and demonstrating its use for nonlinear soil-isolatorstructure systems. A sliding mode controller able to deal with both system nonlinearities and wide range of potential uncertainties in such tests is designed and validated using a nonlinear shake table with a nonlinear specimen. By simply changing the numerical model and using the same controller and experimental setup, different soil types and ground motions can readily be considered with this approach. Numerical and RTHS results are compared for verification purposes.

Dynamic analysis for anti-symmetric cross-ply and angle-ply laminates for simply supported thick hybrid rectangular plates

Benhenni, Mohamed Amine,Daouadji, Tahar Hassaine,Abbes, Boussad,Adim, Belkacem,Li, Yuming,Abbes, Fazilay Techno-Press 2018 Advances in materials research Vol.7 No.2

In this paper, static and vibration analysis for anti-symmetric cross-ply and angle- ply carbon/glass hybrid laminates rectangular composite plate are presented. In this analysis, the equations of motion for simply supported thick laminated hybrid rectangular plates are derived and obtained through the use of Hamilton's principle. The closed-form solutions of anti-symmetric cross-ply and angle- ply laminates are obtained using Navier solution. The effects of side-to-thickness ratio, aspect ratio, and lamination schemes on the fundamental frequencies loads are investigated. The study concludes that shear deformation laminate theories accurately predict the behavior of composite laminates, whereas the classical laminate theory over predicts natural frequencies. The excellent accuracy of the present analytical solution is confirmed by making some comparisons of the present results with those available in the literature. It can be concluded that the proposed theory is accurate and simple in solving the free vibration behaviors of anti-symmetric cross-ply and angle- ply hybrid laminated composite plates.

Numerical study on fire resistance of cyclically-damaged steel-concrete composite beam-to-column joints

Zhongnan Ye,Amin Heidarpour,Shou-Chao Jiang,Yingchao Li,Guoqiang Li 국제구조공학회 2022 Steel and Composite Structures, An International J Vol.43 No.5

Post-earthquake fire is a major threat since most structures are designed allowing some damage during strong earthquakes, which will expose a more vulnerable structure to post-earthquake fire compared to an intact structure. A series of experimental research on steel-concrete composite beam-to-column joints subjected to fire after cyclic loading has been carried out and a clear reduction of fire resistance due to the partial damage caused by cyclic loading was observed. In this paper, by using ABAQUS a robust finite element model is developed for exploring the performance of steel-concrete composite joints in post-earthquake fire scenarios. After validation of these models with the previously conducted experimental results, a comprehensive numerical analysis is performed, allowing influential parameters affecting the post-earthquake fire behavior of the steel-concrete composite joints to be identified. Specifically, the level of pre-damage induced by cyclic loading is regraded to deteriorate mechanical and thermal properties of concrete, material properties of steel, and thickness of the fire protection layer. It is found that the ultimate temperature of the joint is affected by the load ratio while fire-resistant duration is relevant to the heating rate, both of which change due to the damage induced by the cyclic loading.

Determinants of Coopetition Relationships in International Joint Ventures for High-Speed Rail Projects

Yanliang Niu,Huimin Li,Kunhui Ye,Amin Mahmoudi,Xiaopeng Deng 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.5

The mileage of high-speed rail (HSR) is expected to grow in the foreseeable future. Fierce international competition and HSR business uniqueness have facilitated the broad application of international joint ventures (IJVs) globally. However, the interaction between competition and cooperation complicates IJVs, and IJVs partners’ implementation has rarely been informed concerning the fluent operation of IJVs for HSR projects. This study aims to examine the determinants of IJVs coopetition for HSR projects. We identified 35 variables along with their clusters through literature review and pilot study, and collected data from the international HSR industry using a questionnaire survey. Eight clusters verified by the confirmatory factor analysis come from three levels: macro-level, project-level, and firm-level. Based on the partial least squares structural equation modeling (PLS-SEM), a path model for the coopetition relationship has been established, demonstrating that macro-level and project-level determinants affect the coopetition relationship via the firm-level determinants. Furthermore, the path model indicates recommendations corresponding to various situations (isolating situation, partnering situation, contending situation, and adapting situation) for IJVs members to find a way to improve the coopetition relationship. Thus, this study not only contributes to the existing knowledge body on coopetition theory, but also enhances HSR contractors’ comprehension of the coopetition relationship determinants as well as the interactions.

Experimental study on cyclically-damaged steel-concrete composite joints subjected to fire

Zhongnan Ye,Shouchao Jiang,Amin Heidarpour,Yingchao Li,Guoqiang Li 국제구조공학회 2019 Steel and Composite Structures, An International J Vol.30 No.4

Earthquake and fire are both severe disasters for building structures. Since earthquake-induced damage will weaken the structure and reduce its fire endurance, it is important to investigate the behavior of structure subjected to post-earthquake fire. In this paper, steel-concrete composite beam-to-column joints were tested under fire with pre-damage caused by cyclic loads. Beforehand, three control specimens with no pre-damage were tested to capture the static, cyclic and fire-resistant performance of intact joints. Experimental data including strain, deflection and temperature recorded at several points are presented and analyzed to quantify the influence of cyclic damage on fire resistance. It is indicated that the fire endurance of damaged joints decreased with the increase of damage level, mainly due to faster heating-up rate after cyclic damage. However, cracks induced by cyclic loading in concrete are found to mitigate the concrete spalling at elevated temperatures. Moreover, the relationship between fire resistance and damage degree is revealed from experimental results, which can be applied in fire safety design and is worthwhile for further research.

Cross-Linked Poly(cyclotriphosphazene-co-phloretin) Microspheres and Their Application for Controlled Drug Delivery

Sahid Mehmood,Haojie Yu,Li Wang,Md Alim Uddin,Bilal Ul Amin,Fazal Haq,Shah Fahad,Muhammad Haroon 한국고분자학회 2022 Macromolecular Research Vol.30 No.9

In this work, cross-linked poly(cyclotriphosphazene-co-phloretin) (PCTPPT) microspheres were synthesized and characterized by Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscope (SEM). In FT-IR spectra, the new appeared bands at 1009 cm-1 and 1132 cm-1 confirmed the successful polymerization between hexachlorocyclotriphosphazene (HCCP) and phloretin (Pht). While the SEM results showed that the size of the microspheres was strongly dependent on the HCCP:Pht mole ratio. The crystalline nature of the PCTPPT microspheres was checked by X-ray diffraction (XRD) and provided evidence for the successful preparation of the microspheres. The thermal stability of the PCTPPT microspheres was investigated by thermogravimetric analysis (TGA). The obtained TGA results showed that the increase in thermal stability was attributed to the highly cross-linked covalently bonded structure of PCTPPT microspheres. The particle size distribution was determined by dynamic light scattering (DLS) and the results showed that the decreased HCCP:Pht mole ratio increases the size of the microspheres. The PCTPPT-3 microspheres were used as drug carriers for a model drug camptothecin (CPT). The experimental findings showed a cumulative release of 41.0% in pH 4.0 and 32.6% in pH 7.4 after 350 h and the PCTPPT-3/CPT microspheres have good drug loading capability and controlled release property for CPT.