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Chinese Journal of Chemical Engineering 2024年第5期69卷 238-249页

作者： Yuehua Yao Fan Wang Yinguang Xu Zishuai Xu lizhen chen Jianlong Wang School of Chemistry and Chemical Engineering North University of ChinaTaiyuan 030051China Gansu Yinguang Chemical Industry Group Co.Ltd. Baiyin 730900China

In order to remove hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX),the main impurity,in process of polymorphic transformation of octrahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HMX),the solubility ofβ-HMX and RDX in acetonitrile(ACN)+water in the temperature range of 288.15-333.15 K and in nitric acid(HNO_(3))+water in the temperature range of 298.15-333.15 K were measured by laser dynamic method.The results showed that the solubility of bothβ-HMX and RDX in binary mixed solvents increased monotonously as the temperature increase at a given solvent composition or with increasing of mole fraction of solvent(ACN and nitric acid).Solubility data were well correlated by the modified Apelblat equation,Jouyban-Acree model,Yaws equation and van't Hoff equation,and the Yaws equation achieved the best fitting results according to the relative error and the mean square error root.Furthermore,the solubility ofβ-HMX and RDX in binary mixed solvent was compared,based on the solubility difference and the solvent's own properties,the best separation degree ofβ-HMX and RDX was found when the mole fraction of nitric acid was 0.22 at room temperature,which provided data support for HMX crystallization in mixed solvent.The solubility differences between RDX andβ-HMX in mixed solvents were explained from the formation of intermolecular and intramolecular hydrogen bonds.

关键词： Solubility Octrahydro-1 3 5 7-tetranitro-1 3 5 7-tetrazocine Hexahydro-1 3 5-trinitro-1 3 5-triazine Separation Model Hydrogen bond

Efficient SVV stabilized triangular spectral element methods for incompressible flows of high Reynolds numbers

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Advances in Aerodynamics 2022年第1期4卷 58-77页

作者： lizhen chen Tao Tang Chuanju Xu Beijing Computational Science Research Center Beijing100193People’s Republic of China Division of Science and Technology BNU-HKBU United International CollegeZhuhaiGuangdongPeople’s Republic of China Guangdong Provincial Key Laboratory of Computational Science and Material Design Southern University of Science and TechnologyShenzhenPeople’s Republic of China School of Mathematical Sciences and Fujian Provincial Key Laboratory of Mathematical Modeling and High-Performance Scientific ComputingXiamen UniversityXiamen361005People’s Republic of China

In this paper,we propose a spectral vanishing viscosity method for the triangular spectral element computation of high Reynolds number incompressible flows.This can be regarded as an extension of a similar stabilization technique for the standard spectral element method.The difficulty of this extension lies in the fact that a suitable definition of spectral vanishing viscosity operator in non-structured elements does not exist,and it is not clear that if a suitably defined spectral vanishing viscosity provides desirable dissipation for the artificially accumulated energy.The main contribution of the paper includes:1)a well-defined spectral vanishing viscosity operator is proposed for non-standard spectral element methods for the Navier-Stokes equations based on triangular or tetrahedron partitions;2)an evaluation technique is introduced to efficiently implement the stabilization term without extra computational cost;3)the accuracy and efficiency of the proposed method is carefully examined through several numerical examples.Our numerical results show that the proposed method not only preserves the exponential convergence,but also produces improved accuracy when applied to the unsteady Navier-Stokes equations having smooth solutions.Especially,the stabilized triangular spectral element method efficiently stabilizes the simulation of high Reynolds incompressible flows.

关键词： Navier-Stokes equations Triangular spectral element method Spectral vanishing viscosity

Solubility and metastable zone width measurement of 2,4-diaminobenzenesulfonic acid in(H_(2)SO_(4)+H_(2)O)system

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Chinese Journal of Chemical Engineering 2022年第4期35卷 384-391页

作者： Fanfan Shen lizhen chen Pengbao Lian Jianlong Wang Duanlin Cao School of Chemical Engineering and Technology North University of ChinaTaiyuan 030051China

The equilibrium solubility of 2,4-diaminobenzenesulfonic acid and super solubility as well as metastable zone width were measured in(H_(2)SO_(4)+H_(2)O) system by the laser dynamic method at elevate temperature range from 298.15 K to 338.15 K.2,4-Diaminobenzenesulfonic acid solubility dependence on the temperature and solvent composition were correlated by the modified Apelblat equation,(CNIBS)/Redlich-Kister model and Jouyban-Acree model.The correlated results by three correlation models were in good accord with the experimental values according to relative average deviations(RD),root-mean-square deviations(RMSD),and correlation coefficients(R^(2)).The metastable zone width increased with temperature and sulfuric acid content.The dissolution enthalpy,dissolution entropy and the Gibbs energy were calculated from the experimental values,which indicated that dissolution process of the 2,4-diaminobenzenesulfonic acid was endothermic.The solubility and calculation models of 2,4-diaminobenzenesulfonic acid in(sulfuric acid+water)system could provide the basic data to the crystallization and purifying of the 2,4-diaminobenzenesulfonic acid.

关键词： 2 4-Diaminobenzenesulfonic acid Solubility Correlation Metastable zone width

Crystallization thermodynamics of 2,4(5)-dinitroimidazole in binary solvents

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Chinese Journal of Chemical Engineering 2023年第5期57卷 173-182页

作者： Pengbao Lian lizhen chen Dan He Guangyuan Zhang Zishuai Xu Jianlong Wang School of Chemical Engineering and Technology North University of ChinaTaiyuan 030051China Shanxi North Xingan Chemical Industry Co.Ltd China North Industries Group Corporation LimitedTaiyuan 030008China Gansu Yinguang Chemical Industry Group Co. LtdBaiyin 730900China

2,4(5)-Dinitroimidazole(2,4(5)-DNI)is an important organic intermediate,and itself can also be used for energetic material.In this work,the solubility of 2,4(5)-DNI in(methanol+water,acetonitrile+water,acetone+water)binary solvents were measured by using a dynamic test method from 278.15 K to 323.15 K under 101.1 k Pa.The Jouyban–Acree model,van't Hoff–Jouyban–Acree model,Apelblat–Jouyb an–Acree model,Ma model,and Sun model were used to correlate the experimental data.The values of relative average deviation(RAD)and root-mean-square deviation(RMSD)were very small,indicating that the error between the experimental value and the correlated value was very small.The thermodynamic parameters such as dissolution enthalpy,dissolution entropy and Gibbs energy were calculated based on solubility data.High-purity of 2,4(5)-DNI was efficiently obtained by using cooling and dilution crystallization method.

关键词： 2 4(5)-Dinitroimidazole Solid-liquid equilibrium Solubility model Three thermodynamic parameters Cooling and dilution crystallization

Crystallization thermodynamics of 2,4(5)-dinitroimidazole in eleven pure solvents

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Chinese Journal of Chemical Engineering 2022年第8期35卷 236-243页

作者： Pengbao Lian lizhen chen Daozhen Huang Jianxin Xu Zishuai Xu Cai Cao Jiaxiang Zhao Jianlong Wang School of Chemical Engineering and Technology North University of ChinaTaiyuan 030051China Shandong Teneng Environmental Technology Co. Ltd.Dezhou 253000China Gansu Yinguang Chemical Industry Group Co. Ltd.Baiyin 730900China

2,4(5)-Dinitroimidazole(2,4(5)-DNI) is an important energetic material, and it is also an important precursor for the preparation of drugs and energetic materials. In this study, the solubility of 2,4(5)-DNI in eleven pure solvents(chlorobenzene, benzene, 1,2-dichloroethane, toluene, water, isopropyl alcohol,ethyl acetate, acetonitrile, methanol, 1,4-dioxane and acetone) were measured by using a dynamic test method from 278.15 K to 323.15 K under 101.1 kPa. Four solubility models were used to fit the experimental data, which were ideal model, modified Apelblat equation, polynomial empirical equation, and λh equation. Meanwhile, the relative average deviation and root-mean-square deviation between the experimental data and the fitted data were also calculated. Furthermore, the three thermodynamic parameters,i.e., dissolution enthalpy, dissolution entropy and Gibbs energy were obtained based on solubility data.Finally, the crude product of 2,4(5)-DNI was crystallized with acetone as solvent, and the purity of the crystalline product was greater than 99.5%.

关键词： 2,4(5)-Dinitroimidazole Solid-liquid equilibrium Solubility model Three thermodynamic parameters Cooling crystallization

Multifaceted function of YAP/TEAD on chromatin:prospects of‘A non-canonical role of YAP/TEAD is required for activation of estrogen-regulated enhancers in breast cancer’

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Journal of Molecular Cell Biology 2019年第12期11卷 1101-1103页

作者： lizhen chen Zhijie Liu Barshop Institute for Longevity and Aging Studies Department of Cell Systems and AnatomyThe University of Texas Health Science Center at San AntonioSan AntonioTX 78229USA Department of Molecular Medicine Mays Cancer CenterThe University of Texas Health Science Center at San AntonioSan AntonioTX 78229USA

Cellular function and behavior are controlled by various signals during development and disease progression in mammals.It is important to understand how signals ultimately alter the function and structure of DNA regulatory elements,especially enhancers,causing the changes of gene expression patterns.On average,each mature human cell harbors at least^100000 enhancers,but only a small percent of them have the function to activate gene expression.For instance,only^12%–18%of ERα-bound enhancers are active enhancers.How enhancers become functionally active is critical for our overall understanding of enhancer biology and gene regulation.Enhancers are recognized by signaling-dependent DNA binding transcription factors(TFs),resulting in the recruitment of different enhancer activation components that allow distal enhancers to interact with their target promoters through chromatin looping(Plank and Dean,2014).Increasing evidence indicates that the recruitment and switching of enhancer components underlie enhancer activation and the deregulation in enhancer component or architecture profoundly alters signal-regulated transcriptional machineries,leading to developmental defects or diseases.

关键词： activation function instance

Solubility and metastable zone width measurement of 3,4-bis (3-nitrofurazan-4-yl) furoxan (DNTF) in ethanol + water

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Chinese Journal of Chemical Engineering 2017年第5期25卷 646-651页

作者： lizhen chen Liang Song Guanchao Lan Jianlong Wang School of Chemical and Environmental Engineering North University of China

The solubility and supersolubility of 3,4-bis(3-nitrofurazan-4-yl)furoxan(DNTF) in ethanol + water at different operation were determined by laser monitoring system under atmospheric pressure to study the metastable zone width(MSZW). The modified Apelblat equation was adopted to correlate the experimental solubility data, and the correlation result showed perfect consistent with the experimental data. The standard dissolution enthalpy, standard dissolution entropy and Gibbs energy were calculated according to the experimental solubility data. The effect of the cooling rate, stirring rate, temperature and the concentration of ethanol + water on the MSZW was studied. It was found that the MSZW of DNTF increased with the increasing cooling rate, decreasing temperature, decreasing stirring rate and decreasing ratio of water. And the apparent nucleation order of DNTF in ethanol + water was calculated by the relationship between the cooling rate and the MSZW.

关键词：超溶解度介稳区宽度乙醇浓度 DNTF 氧化呋咱水测量激光监测系统

A Unstructured Nodal Spectral-Element Method for the Navier-Stokes Equations

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Communications in Computational Physics 2012年第6期12卷 315-336页

作者： lizhen chen Jie Shen Chuanju Xu School of Mathematical Sciences Xiamen University361005 XiamenChina Department of Mathematics Purdue UniversityWest LafayetteIN47907USA

An unstructured nodal spectral-elementmethod for theNavier-Stokes equations is developed in this paper.The method is based on a triangular and tetrahedral rational approximation and an easy-to-implement nodal basis which fully enjoys the tensorial product property.It allows arbitrary triangular and tetrahedralmesh,affording greater flexibility in handling complex domains while maintaining all essential features of the usual spectral-element method.The details of the implementation and some numerical examples are provided to validate the efficiency and flexibility of the proposed method.

关键词： Navier-Stokes equations unstructured mesh triangular spectral element method

Experimental determination of solubilities and＇supersolubilities of 2,2＇,4,4＇,6,6＇-hexanitrostilbene in different organic solvents

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Chinese Journal of Chemical Engineering 2017年第6期25卷 809-814页

作者： lizhen chen Liang Song Yupeng Gao Aipeng Zhu Duanlin Cao School of Chemical Engineering and Environment North University of China Taiyuan 030051 China

The laser monitor technique was used to determine solubilities and supersolubilities of HNS in N,N-dimethylformamide, dimethyl sulfoxide, acetonitrile, N-methyl-2-pyrrolidone and 1,4-butyrolactone. The experimental solubility values were correlated with λh equation, modified Apelblat equation and NRTL model. Furthermore, the dissolution enthalpy, dissolution entropy and the Gibbs energy of HNS were calculated by the experimental data. The results show that the solubilities of HNS in the above solvents increase with the increasing temperature. Besides, at the same temperature, the order of solubility is N-methyl-2-pyrrolidone > dimethyl sulfoxide > N,N-dimethylformamide > 1,4-butyrolactone > acetonitrile. The temperature dependence of predicted solubility is in agreement with the experimental data.

关键词： HNS Solubility Liquid-solid equilibrium Correlation Laser monitor technique

A Triangular Spectral Method for the Stokes Equations

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Numerical Mathematics(Theory,Methods and Applications) 2011年第2期4卷 158-179页

作者： lizhen chen Jie Shen Chuanju Xu School of Mathematical Sciences Xiamen University361005 XiamenChina Department of Mathematics Purdue UniversityWest LafayetteIN47907USA

A triangular spectral method for the Stokes equations is developed in this paper.The main contributions are two-fold:First of all,a spectral method using the rational approximation is constructed and analyzed for the Stokes equations in a triangular domain.The existence and uniqueness of the solution,together with an error estimate for the velocity,are proved.Secondly,a nodal basis is constructed for the efficient implementation of the method.These new basis functions enjoy the fully tensorial product property as in a tensor-produce domain.The new triangular spectral method makes it easy to treat more complex geometries in the classical spectral-element framework,allowing us to use arbitrary triangular and tetrahedral elements.

关键词： Stokes equations triangular spectral method error analysis