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Novel Cr^(3+)-activated far-red emitting phosphors withβ-Ca_(3)(PO_(4))_(2)-type structure for indoor plant cultivation

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International Journal of Minerals,Metallurgy and Materials 2022年第6期29卷 1286-1294页

作者： Fangyi Zhao zhen song Quanlin Liu Beijing Municipal Key Laboratory of New Energy Materials and Technologies School of Materials Sciences and EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Cr^(3+)-activated far-red and near-infrared phosphors have drawn considerable attention owing to their adjustable emission wavelengths and wide ***,we reported a series of Cr^(3+)-doped phosphors withβ-Ca_(3)(PO_(4))_(2)-type structure,of which Ca_(9)Ga(PO_(4))_(7):Cr^(3+) possessed the highest far-red emission *** an excitation of 440 nm,the Ca_(9)Ga(PO_(4))_(7):Cr^(3+) phosphors exhibited a broad emission band ranging from 650 to 850 nm and peaking at 735 nm,and the broadband superimposed two sharp lines centering at 690 and 698 *** optimal sample Ca_(9)Ga_(0.97)(PO_(4))_(7):0.03 Cr^(3+) had an internal quantum efficiency of 55.7%.The luminescence intensity of the Ca_(9)Ga_(0.97)(PO_(4))_(7):0.03 Cr^(3+) phosphor obtained at 423 K could maintain 68.5%of that at room temperature,demonstrating its outstanding luminescence thermal stability.A phosphor-conversion light-emitting diode was fabricated,indicating that the Ca_(9)Ga(PO_(4))_(7):Cr^(3+) phosphor has potential applications in indoor plant cultivation.

关键词： far-red near-infrared luminescence trivalent chromium ion plant cultivation

Evaluation of COSMO-RS for solid–liquid equilibria prediction of binary eutectic solvent systems

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Green Energy & Environment 2021年第3期6卷 371-379页

作者： zhen song Jingwen Wang Kai Sundmacher Process Systems Engineering Otto-von-Guericke University MagdeburgUniversitätsplatz 2MagdeburgD-39106Germany Process Systems Engineering Max Planck Institute for Dynamics of Complex Technical SystemsSandtorstraße 1MagdeburgD-39106Germany School of Chemical Engineering East China University of Science and Technology130 Meilong RoadShanghai200237China

For the design of eutectic solvents(ESs,usually also known as deep eutectic solvents),the prediction of the solid–liquid equilibria(SLE)between candidate components is of primary *** the present work,the SLE prediction of binary eutectic solvent systems by the COSMO-RS model is systematically evaluated,thereby examining the applicability of this method for ES *** SLE of such systems are first collected exhaustively from the literature,following which COSMO-RS SLE calculations are accordingly carried *** comparing the experimental and predicted eutectic points(eutectic temperature and eutectic composition)of the involved systems,the effects of salt component conformer and COSMO-RS parameterization as well as the applicability for different types of components(specifically the second component paired with the first salt one)are *** distinct performances of COSMO-RS SLE prediction for systems involving different types of components are further interpreted from the non-ideality and fusion enthalpy point of view.

关键词： Eutectic solvents Solid-liquid equilibria prediction COSMO-RS Calculation options Applicability for component types

Spectral Study on the Interactions Among Cu(Ⅱ), Doxorubicin and CopC

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Chemical Research in Chinese Universities 2019年第1期35卷 53-59页

作者： song Yunxi song zhen YANG Binsheng Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education Institute of Molecular ScieneeShanxi UniversityTaiyuan 030006P.R.China Department of Chemistry Taiyuan Normal University Jinzhong 030619P.R.China

Interactions among Cu(Ⅱ),doxorubicin and copper operon C(CopC)have been investigated in detail by means of fluorescence,UV-Vis,IR spectra,isothermal titration calorimetry(ITC)and molecular docking in Tris-HCl buffer(50 mmol/L,pH=7.4,25℃).The results suggest that Cu(Ⅱ)-doxorubicin is formed in a Cu(Ⅱ)to doxorubicin molar ratio of 1:2,and the conditional stability constant,K[Cu(Ⅱ)-doxorubicin]is 1.90×10^9 L^2/mol^2,CopC and doxorubicin can form a 1:1 complex,the conditional stability constant is greater than 10^5 L/*** of doxorabicin causes a conformational change in CopC with the reduction of β-sheet and increase of random coil,and the stability of CopC is ***(Ⅱ),doxorubicin and CopC can form a CopC-Cu(Ⅱ)-doxorubicin ternary *** formation of CopC-Cu(Ⅱ)-doxorubicin reduced greatly the reduction rate of Cu(Ⅱ)by ascorbate(Vc),i.e.,the binding of doxorubicin affects the action of CopC as redox switch.

关键词： Doxorubicin Copper operon C(CopC) Cu(Ⅱ)interaction

DRPS:efficient disk-resident parameter servers for distributed machine learning

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Frontiers of Computer Science 2022年第4期16卷 79-90页

作者： zhen song Yu Gu Zhigang Wang Ge Yu School of Computer Science and Engineering Northeastern UniversityShenyang110819China College of Information Science and Engineering Ocean University of ChinaQingdao266100China

Parameter server(PS)as the state-of-the-art distributed framework for large-scale iterative machine learning tasks has been extensively ***,existing PS-based systems often depend on memory *** memory constraints,machine learning(ML)developers cannot train large-scale ML models in their rather small local ***,renting large-scale cloud servers is always economically infeasible for research teams and small *** this paper,we propose a disk-resident parameter server system named DRPS,which reduces the hardware requirement of large-scale machine learning tasks by storing high dimensional models on *** further improve the performance of DRPS,we build an efficient index structure for parameters to reduce the disk I/O *** on this index structure,we propose a novel multi-objective partitioning algorithm for the ***,a flexible workerselection parallel model of computation(WSP)is proposed to strike a right balance between the problem of inconsistent parameter versions(staleness)and that of inconsistent execution progresses(straggler).Extensive experiments on many typical machine learning applications with real and synthetic datasets validate the effectiveness of DRPS.

关键词： parameter servers machine learning disk resident parallel model

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基于密度泛函理论纤维素热解机理热力学研究

原子与分子物理学报 2025年第5期42卷 1-6页

作者：周俊杰陈曦汤松臻李智聪郑州大学机械与动力工程学院郑州450001

为了探究纤维素的热解机理,参考相关的实验结果,以纤维素单体模化物为研究对象,采用密度泛函理论的方法,以b3lyp/6-31++g(d,p)为基,对纤维素单体热解反应生成乙醇醛和CO_(2)小分子的反应机理进行动力学研究.纤维素单体热解生成乙醇醛和C... 详细信息

为了探究纤维素的热解机理,参考相关的实验结果,以纤维素单体模化物为研究对象,采用密度泛函理论的方法,以b3lyp/6-31++g(d,p)为基,对纤维素单体热解反应生成乙醇醛和CO_(2)小分子的反应机理进行动力学研究.纤维素单体热解生成乙醇醛和CO_(2)的反应路径为纤维素单体首先开环,之后裂解生成四糖片段M2和乙醇醛P1,能垒最高为339.1 kJ/mol,四糖片段M2经过脱水形成烯酮结构后再与水分子作用生成羧基,最后发生脱羧反应生成CO_(2),能垒较高为290.1 kJ/mol,不容易发生,整个过程放出98.9 kJ/mol的热量,并对路径反应物、中间体和过渡态进行几何构型全优化,过渡态的振动和频率计算,同时进行不同温度下(400 K、600 K、800 K、1000 K、1200 K)热解过程的热力学分析,对纤维素的热解机理研究将对生物质的热裂解机理研究有重要的意义.

关键词：纤维素热解密度泛函理论反应机理

Intervalence charge transfer of Cr^(3+)-Cr^(3+) aggregation for NIR-Ⅱ luminescence

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Light(Science & Applications) 2023年第8期12卷 1686-1695页

作者： Shengqiang Liu Jingxuan Du zhen song Chonggeng Ma Quanlin Liu Beijing Municipal Key Laboratory of New Energy Materials and Technologies School of Materials Sciences and EngineeringUniversity of Science and Technology BeijingBeijing 100083China School of Optoelectronic Engineering&CQUPT-BUL Innovation Institute Chongqing University of Posts and TelecommunicationsChongqing 400065China

The increasing demand for high-contrast biological imaging,non-destructive testing,and infrared night vision can be addressed by the development of high-performance NIR light-emitting *** lanthanide(Ln^(3+))with sharp-line multiplets and isolated Cr^(3+)with NIR-I emission,this study reports the first-ever NIR-Ⅱ broadband luminescence based on the intervalence charge transfer(IVCT)of Cr^(3+)-Cr^(3+)aggregation in gallate *** particular,LaMgGa11O19:0.7Cr^(3+)exhibits dual-emission(NIR-I,890 nm and NIR-Ⅱ,1200 nm)with a full width at half maximum(FWHM)of 626 nm under 450 nm blue LED ***,this dual-emission exhibits anti-thermal quenching behavior(432%@290 K),attributed to the energy transfer among multiple Cr^(3+)*** absorption spectra,lifetimes decay(2.3 ms),and electron paramagnetic experiments reveal the NIR-Ⅱ luminescence of the Cr^(3+)-Cr^(3+)→Cr^(2+)-Cr^(4+)IVCT *** application of LaMgGa_(11)O_(19)∶0.7Cr^(3+)in NIR-Ⅱ biological imaging as an optical contrast agent,non-destructive testing,and night vision is *** work provides new insights into broadband NIR-Ⅱ luminescence under UV-NIR excitation based on the IVCT of Cr^(3+)-Cr^(3+)aggregation.

关键词： transition. materials. luminescence

Field synergy principle of heat and mass transfer

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Chinese Science Bulletin 2009年第24期54卷 4604-4609页

作者： WU LiangBo LI zhen song YaoZu Key Laboratory of Heat Transfer and Energy Conversion of Beijing Municipality School of Aerospace Tsinghua University Beijing100084 China

Simultaneous heat and mass transfer widely exists in nature and engineering, and it is of vital importance to enhance heat and mass transfer efficiency. In this paper, field synergy equation of heat and mass transfer is derived from its energy equation. Results show that the total transferred heat (including the conducted heat and the heat transferred by mass diffusion through the heat transfer interface) is determined by the values of fluid velocity and enthalpy gradient as well as the value of synergy angle α of velocity vector and enthalpy gradient field. Decreasing the value of α enhances the heat and mass transfer. This means the higher the synergy of velocity vector and enthalpy gradient field, the higher the total transferred heat. By the synergy principle of heat and mass transfer, some methods may be developed to improve the heat and mass transfer efficiency.

关键词：传热传质增效流体速度协同效应传质效率能量方程梯度场矢量和

Synthesis of cyclicβ-silylenones via oxidative rearrangement of tertiaryα-hydroxy allylsilanes with PCC

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Chinese Chemical Letters 2011年第3期22卷 306-309页

作者： Xia Wu Jian Lei zhen Lei song Key Laboratory of Drug-Targeting of Education Ministry and Department of Medicinal Chemistry West China School of Pharmacy Sichuan University Chengdu 610041 China

An oxidative rearrangement of cyclic tertiary a-hydroxy allylsilanes has been carried out in refluxing ClCH_2CH_2Cl with pyridinium chlorochromate（PCC）.The reaction provides a convenient method to synthesize cyclic... 详细信息

关键词： Pyridinium chlorochromate Oxidative rearrangement Cyclicβ-silylenones

Stability of proteins with multi-state unfolding behavior

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Science China Chemistry 2012年第7期55卷 1351-1357页

作者： YANG BinSheng song zhen zhenG XiaoYan ZHAO YaQin Institute of Molecular Science Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of EducationShanxi UniversityTaiyuan 030006China

A new model used to calculate the free energy change of protein unfolding is presented. In this model, proteins are considered to be composed of structural elements. The unfolding of a structural element obeys a two-state mechanism and the free energy change of the element can be obtained by a linear extrapolation method. If a protein consists of the same structural elements, its unfolding will displays a two-state process, and only the average structural element free energy change 〈△G0 element（H2O）〉 can be measured. If protein consists of completely different structural elements, its unfolding will show a multi-state behavior. When a protein consists of n structural elements its unfolding will shows a （n＋1）-state behavior. A least-squares fitting can be used to analyze the contribution of each structural element to the protein and the free energy change of each structural element can be obtained by using linear extrapolation to zero denaturant concentration, not to the start of each transition. The measured △Gn protein（H2O） is the sum of the free energy change for each structural element. Using this new model, we can not only analyze the stability of various proteins with similar structure and similar molecular weight, which undergo multi-state unfolding processes, but also compare the stability of proteins with different structures and molecular weights using the average structural element free energy change 〈△G0 element（H2O）〉. Although this method cannot completely provide the exact free energy of proteins, it is better than current methods.

关键词： new model protein stability multi-state unfolding CopC