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Predicting the Mechanical Properties of Polyurethane Elastomers Using Machine Learning

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Chinese Journal of Polymer Science 2023年第3期41卷 422-431,I0009页

作者： Fang Ding lun-yang liu Ting-Li liu Yun-Qi Li Jun-Peng Li Zhao-Yan Sun State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China Department of Polymer Materials and Engineering College of Materials and MetallurgyGuizhou UniversityGuiyang 550025China State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Platinum Metals Sino-Platinum Metals Co.Ltd.Ltdunming 650106China

Bridging the gap between the computation of mechanical properties and the chemical structure of elastomers is a long-standing *** fill the gap,we create a raw dataset and build predictive models for Young’s modulus,tensile strength,and elongation at break of polyurethane elastomers(PUEs).We then construct a benchmark dataset with 50.4%samples remained from the raw dataset which suffers from the intrinsic diversity problem,through a newly proposed recursive data elimination *** coefficients of determination(R^(2)s)from predictions are improved from 0.73-0.78 to 0.85-0.91 based on the raw and the benchmark *** fitting of stress-strain curves using the machine learning model shows a slightly better performance than that for one of the well-performed constitutive models(e.g.,the Khiêm-Itskov model).It confirmed that the black-box machine learning models are feasible to bridge the gap between the mechanical properties of PUEs and multiple factors for their chemical structures,composition,processing,and measurement *** accurate prediction for these curves is still a *** release the raw dataset and the most representative benchmark dataset so far to call for more attention to tackle the longstanding gap problem.

关键词： Mechanical properties Stress-strain curves Polyurethane elastomers Machine learning Benchmark dataset

Preparation and properties of high-energy-density aluminum/boroncontaining gelled fuels

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Chinese Journal of Chemical Engineering 2024年第1期65卷 230-242页

作者： Yi Chen Kang Xue yang liu lun Pan Xiangwen Zhang Ji-Jun Zou Key Laboratory for Green Chemical Technology of the Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Collaborative Innovative Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Zhejiang Institute of Tianjin University Ningbo 315201China

Energetic nanofluid fuel has caught the attention of the field of aerospace liquid propellant for its high energy density(HED), but it suffers from the inevitable solid-liquid phase separation problem. To resolve this problem, herein we synthesized the high-Al-/B-containing(up to 30%(mass)) HED gelled fuels, with low-molecular-mass organic gellant Z, which show high net heat of combustion(NHOC), density, storage stability, and thixotropic properties. The characterizations indicate that the application of energetic particles to the gelled fuels obviously destroys their fibrous network structures but can provide the new particle-gellant gelation microstructures, resulting in the comparable stability between 1.0%(mass) Z/JP-10 + 30%(mass) Al or B and pure JP-10 gelled fuel. Moreover, the gelled fuels with high-content Al or B exhibit high shear-thinning property, recovery capability, and mechanical strength, which are favorable for their storage and utilization. Importantly, the prepared 1.0%(mass) Z/JP-10 + 30%(mass) B(or 1.0%(mass) Z/JP-10 + 30%(mass) Al) shows the density and NHOC 1.27 times(1.30) and 1.43 times(1.21)higher than pure JP-10, respectively. This work provides a facile and valid approach to the manufacturing of HED gelled fuels with high content of energetic particles for gel propellants.

关键词： Gelled fuels Energetic aluminum/boron Low-molecular-mass organic gellant Fuel property

Relationship between hydrogenation degree and pyrolysis performance of jet fuel

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Chinese Journal of Chemical Engineering 2024年第4期68卷 35-42页

作者： Qing liu Tinghao Jia lun Pan Jijun Zou Xiangwen Zhang Key Laboratory for Green Chemical and Technology School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Zhejiang Institute of Tianjin University Ningbo 315201China Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China

Understanding the relationship between the chemical composition and pyrolysis performance of endothermic hydrocarbon fuel(EHF) is of great significance for the design and optimization of advanced EHFs. In this work, the effect of deep hydrogenation on the pyrolysis of commercial RP-3 is *** with different hydrogenation degrees were obtained by the partially and completely catalytic hydrogenation and their pyrolysis performances were investigated using an apparatus equipped with an electrically heated tubular reactor. The results show that with the increase of hydrogenation degree, fuel conversion almost remains constant during the pyrolysis process(500-650°C, 4 MPa);however, the heat sink increases slightly, and the anti-coking performance significantly improves, which are highly related to their H/C ratios. Detailed characterisations reveal that the difference of the pyrolysis performance can be ascribed to the content of aromatics and cycloalkanes: the former are prone to initiate secondary reactions to form coking precursors, while the latter could act as the hydrogen donor and release hydrogen, which will terminate the radical propagation reactions and suppress the coke deposition. This work should provide the guidance for upgrading EHFs by modulating the composition of EHFs.

关键词： RP-3 Fuel Pyrolysis Hydrogenation Deposition

Optimal Shape Factor and Fictitious Radius in the MQ-RBF:Solving Ill-Posed Laplacian Problems

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 3189-3208页

作者： Chein-Shan liu Chung-lun Kuo Chih-Wen Chang Center of Excellence for Ocean Engineering Taiwan Ocean UniversityKeelung202301TaiwanChina Department of Mechanical Engineering National United UniversityMiaoli36063TaiwanChina

To solve the Laplacian problems,we adopt a meshless method with the multiquadric radial basis function(MQRBF)as a basis whose center is distributed inside a circle with a fictitious radius.A maximal projection technique is developed to identify the optimal shape factor and fictitious radius by minimizing a merit function.A sample function is interpolated by theMQ-RBF to provide a trial coefficient vector to compute the merit *** can quickly determine the optimal values of the parameters within a preferred rage using the golden section search *** novel method provides the optimal values of parameters and,hence,an optimal MQ-RBF;the performance of the method is validated in numerical ***,nonharmonic problems are transformed to the Poisson equation endowed with a homogeneous boundary condition;this can overcome the problem of these problems being *** optimal MQ-RBF is extremely *** further propose a novel optimal polynomial method to solve the nonharmonic problems,which achieves high precision up to an order of 10^(−11).

关键词： Laplace equation nonharmonic boundary value problem Ill-posed problem maximal projection optimal shape factor and fictitious radius optimal MQ-RBF optimal polynomial method

Photoinduced transposed Paternò-Büchi reaction for effective synthesis of high-performance jet fuel

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Chinese Journal of Chemical Engineering 2024年第3期67卷 39-48页

作者： Jinxiu Hu Xianlong liu Yi liu Kang Xue Chengxiang Shi Xiangwen Zhang Li Wang Ji-Jun Zou lun Pan Key Laboratory for Green Chemical Technology of the Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Zhejiang Institute of Tianjin University Ningbo 315201China Collaborative Innovative Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China

High-energy-density fuels are important for volume-limited aerospace vehicles,but the increase in fuel energy density always leads to poor cryogenic ***,we investigated the transposed Paternò-Büchi reaction of biomass cyclic ketone and cyclic alkene to synthesize a new kind of alkyl-substituted polycyclic hydrocarbon fuel with high energy density and good cryogenic *** triplet-energy-quenching results and phosphorescent emission spectra reveal the sensitization mechanism of the reaction,including photosensitizer excitation,triplettriplet energy transfer,cyclization,and relaxation,and the possible reaction path was revealed by the density functional theory(DFT)*** reaction conditions of photosensitizer type and addition,molar ratio of substrates,reaction temperature,and incident light intensity were optimized,with the target product yield achieving 65.5%.Moreover,the reaction dynamics of the reaction rate versus the light intensity are *** the hydrogenation-deoxygenation reaction,three fuels with a high density of 0.864-0.938 g·ml^(-1) and a low freezing point of<-55℃ are *** work provides a benign and effective approach to synthesize high-performance fuels.

关键词： High-energy-density fuel Transposed Patern-oeBüchi reaction Kinetics Bioenergy Photochemistry

Highly Accurate Golden Section Search Algorithms and Fictitious Time Integration Method for Solving Nonlinear Eigenvalue Problems

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1317-1335页

作者： Chein-Shan liu Jian-Hung Shen Chung-lun Kuo Yung-Wei Chen Center of Excellence for Ocean Engineering Taiwan Ocean UniversityKeelung202301TaiwanChina Department of Marine Engineering Taiwan Ocean UniversityKeelung202301TaiwanChina

This study sets up two new merit functions,which are minimized for the detection of real eigenvalue and complex eigenvalue to address nonlinear eigenvalue *** each eigen-parameter the vector variable is solved from a nonhomogeneous linear system obtained by reducing the number of eigen-equation one less,where one of the nonzero components of the eigenvector is normalized to the unit and moves the column containing that component to the right-hand side as a nonzero input vector.1D and 2D golden section search algorithms are employed to minimize the merit functions to locate real and complex ***,the real and complex eigenvectors can be computed very accurately.A simpler approach to the nonlinear eigenvalue problems is proposed,which implements a normalization condition for the uniqueness of the eigenvector into the eigenequation *** real eigenvalues can be computed by the fictitious time integration method(FTIM),which saves computational costs compared to the one-dimensional golden section search algorithm(1D GSSA).The simpler method is also combined with the Newton iterationmethod,which is convergent very *** the proposed methods are easily programmed to compute the eigenvalue and eigenvector with high accuracy and efficiency.

关键词： Nonlinear eigenvalue problem quadratic eigenvalue problem two new merit functions golden section search algorithm fictitious time integration method

Design,synthesis,and biological evaluation of 1,2,4-triazole derivatives as potent antitubercular agents

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Chinese Chemical Letters 2024年第3期35卷 326-331页

作者： Yu Wen Shichun lun Yuxue Jiao Wei Zhang Tianyu Hu Ting liu Fan yang Jie Tang Bing Zhang William R.Bishai Li-Fang Yu Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China Center for Tuberculosis Research Department of MedicineDivision of Infectious DiseaseJohns Hopkins School of MedicineBaltimoreMD21231-1044United States Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China Shanghai Key Laboratory of Green Chemistry and Chemical Process School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China

Inhibition of mycobacterial membrane protein large 3(MmpL3)thereby affecting the mycolic acid biosynthetic pathway has been proven to be an effective strategy for developing antitubercular *** on the X-ray crystal structure of MmpL3 inhibitor complexes,a series of novel 1,2,4-triazole derivatives were designed,synthesized and evaluated antitubercular activity against Mtb strain *** structure–activity relationship exploration resulted in the identification of compounds 21 and 28,which possess potent antitubercular activity against Mtb strain H37Rv[minimum inhibitory concentration(MIC)=0.03–0.13μg/mL]and the clinical isolates of multidrug resistance(MDR)and extensive drug resistance(XDR)tuberculosis(MIC=0.06–1.0μg/mL).Moreover,compounds 21 and 28 showed neglectable cytotoxicity(IC_(50)≥32μg/mL)to the mammalian Vero cells and favorable physicochemical and pharmacokinetic properties according to the in silico absorption,distribution,metabolism and excretion(ADME)***,the potential target of representative 1,2,4-triazole 28 was identified to be MmpL3 using a microscale thermophoresis(MST)assay.

关键词： Tuberculosis MDR and XDR-TB MmpL3 inhibitor 1 2 4-Triazole Structure-based drug design

高分子材料大数据研究:共性基础、进展及挑战

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高分子学报 2022年第6期53卷 564-580页

作者：刘伦洋丁芳李云琦中国科学院长春应用化学研究所高分子化学与物理国家重点实验室长春130022 中国科学技术大学应用化学与工程学院合肥230026

介绍了作为一种新的认知范式,大数据研究常见和前沿算法及其应用在高分子材料研究中的共性基础,围绕材料的基础与应用研究聚焦的定量组成-工艺-结构-性质-性能关系,剖析了该关系中的要素和可数值化、定量化的资源和途径.进而系统介绍近... 详细信息

介绍了作为一种新的认知范式,大数据研究常见和前沿算法及其应用在高分子材料研究中的共性基础,围绕材料的基础与应用研究聚焦的定量组成-工艺-结构-性质-性能关系,剖析了该关系中的要素和可数值化、定量化的资源和途径.进而系统介绍近4年在高分子材料的合成与自组装、机械热性质、光电声磁性质、分离性质和加工性质等方面大数据研究的一些典型进展,梳理了当前高分子材料大数据研究的难题和挑战,对这一新兴快速发展方向和一段时间内可能的突破进行了展望.

关键词：高分子材料大数据组成-工艺-结构-性质-性能关系计算辅助材料设计

PbrARF4 contributes to calyx shedding of fruitlets in ‘Dangshan Suli’ pear by partly regulating the expression of abscission genes

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Horticultural Plant Journal 2024年第2期10卷 341-354页

作者： Guoling Guo Pengfei Wei Tao Yu Haiyan Zhang Wei Heng lun liu Liwu Zhu Bing Jia School of Horticulture Anhui Agricultural UniversityHefeiAnhui 230036China Huayuan Foreign Language School Zhejiang Normal UniversityJinhuaZhejiang 322100China Agricultural Experimental Center of Guiyang Guiyang Agriculture and Rural BureauGuiyangGuizhou 550018China

Fruitlet calyx shedding in pear plants is apparently regulated via numerous pathways that involve both environmental triggers and phytohormones cues such as auxin. In this study, we found at 10 days after full bloom (DAFB) higher levels of indoleacetic acid (IAA) and tryptophan (Trp) in calyx persistence fruitlet (CPF) than calyx shedding fruitlet (CSF) ofDanshan Suli’ pear (Pyrus bretschneideri Rhed.). Consisting with this, the activity of indolealdehyde oxidase (IAAIdO), which promotes IAA synthesis, was remarkably increased, and that of peroxidase(POD), which degrades IAA, dropped markedly in CPF but not in CSF. Further, qRT-PCR results revealed that most of 31 PbrARFs (encoding auxin response factors) in Pyrus bretschneideri were highly expressed in CPF, whereas PbrARF4, PbrARF24 and PbrARF26 were significantly downregulated in CPF vis-a-vis CSF. Phylogenetic analysis revealed that 6 PbrARFs clustered in the group III, where PbrARF4 showed the closest affinity with AtARF1 that promotes organ abscission, indicating a putative role of PbrARF4 in mediating the process of calyx shedding in pear. In fact, the ectopic overexpression of PbrARF4 in Solanum lycopersicum resulted in an earlier-formed and deeper abscission layer (AL) in the transgenic plants, whose calyxes were more prone to wilt at the mature red stage (MR) compared with the control plants (wild-type). More importantly, expression levels of the abscission genes SILS and Sl Cel2 in transgenic plants overexpressing PbrARF4 were significantly upregulated in comparation with the WT, whereas those of Sl BI and Sl TAPG2 were considerably inhibited. Further, PbrJOINTLESS and PbrIDA,the two genes related to calyx shedding in pear, were up-regulated more in CSF than CPF. The findings contribute to a better understanding of PbrARFs involved in fruitlet calyx shedding of pear, which could prove beneficial to improving the quality of pear fruit.

关键词： Pear Pyrus bretschneideri Rehd Calyx shedding IAA PbrARF4 Abscission genes