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Machine Learning-Driven Prediction of Ethylene Homopolymerization Reaction Performance: Fi Catalyst Activity, Polyethylene Molecular Weight, and Molecular Weight Distribution

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SSRN 2025年

作者： Yang, Tao Liang, Jie Qin, Yao Zhou, Xiaokun He, Jing Wang, Yuan Zhu, Yuanqin Wei, Zengxi Zhao, Shuangliang Guangxi University China Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology School of Chemistry and Chemical Engineering Guangxi University Nanning530004 China State Key Laboratory of Polyolefins and Catalysis Shanghai200062 China Shanghai Research Institute of Chemical Industry Co. Ltd Shanghai200062 China

The design of multifunctional polyethylene is critically dependent on the careful selection of catalysts and the precise control of reaction conditions during the process of ethylene homopolymerization. Phenoxy-imine-based (FI) catalysts, which is renowned for its exceptional ability to produce high molecular weight polyethylene with a narrow molecular weight distribution, has traditionally undergone optimization through inefficient trial-and-error methods. This study presents a machine learning (ML) technique designed to forecast catalyst activity, molecular weight, and molecular weight distribution in the context of ethylene homopolymerization, with the goal of refining the catalyst design process. Findings suggest that the ligands of FI catalysts play a crucial role in determining the molecular weight distribution. We devise a feature engineering approach that integrates the spatial site resistance egenvolume of FI catalyst ligands, which is quantified using the percentage of buried volume (%V buried). Among the seven ML algorithms utilizing, gradient boosted regression (GBR) shows remarkable prediction accuracy in relation to catalytic activity, molecular weight and molecular weight distribution, with R² values of 0.9949, 0.9848 and 0.9608, respectively. These results highlight the promising potential of data-driven models in forecasting ethylene polymerization performance, potentially minimizing the requirement for extensive experimental catalyst development. Furthermore, this methodology is equally suitable for other catalyst systems, including metallocene catalysts, presenting a wide range of applications within the field of polymer science. © 2025, The Authors. All rights reserved.

关键词： Ligands

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Self-assembly of biomimetic light-harvesting complexes capable of hydrogen evolution

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Green Energy & Environment 2017年第1期2卷 58-63页

作者： Kai Liu Manzar Abass Qianli Zou Xuehai Yan State Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences University of Chinese Academy of Sciences Center for Mesoscience Institute of Process EngineeringChinese Academy of Sciences

Biomimetics provides us a new perspective to understand complex biological process and strategy to fabricate functional materials. However,a great challenge still remains to design and fabricate biomimetic materials using a facile but effective method. Here, we develop a biomimetic light harvesting architecture based on one-step co-assembly of amphiphilic amino acid and porphyrin. Amphiphilic amino acid can self-assemble into nanofibers via π-stacking and hydrogen binding interactions. Negatively charged porphyrin adsorbs on the surface of the assembled nanofibers through electrostatic force, and the nanofibers further organize into porous urchin-like microspheres induced presumably by hydrophobic interaction. The assembled amphiphilic amino acid nanofibers work as a template to tune the organization of porphyrin with an architecture principle analogous to natural light harvesting complex. The co-assembled microspheres exhibit enhanced light capture due to the light reflection in the porous structure. Reaction center(platinum nanoparticles) can be effectively coupled with the light harvesting microspheres via photoreduction. After visible light illumination, hydrogen evolution occurs on the hybrid microspheres.

关键词： Light-harvesting Amino acid Porphyrin Co-assembly Hydrogen evolution

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Effect of bovine serum albumin on the micellization of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) block copolymers in aqueous solutions by fluorescence spectroscopy

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Science China Chemistry 2006年第6期49卷 541-549页

作者： GUO Chen WANG Jing LIANG Xiangfeng ZHENG Lili LIU Huizhou Laboratory of Separation Science and Engineering State Key Laboratory of Biochemical EngineeringInstitute of Process EngineeringGraduate University of Chinese Academy of SciencesBeijing 100080China

Effect of bovine serum albumin(BSA)on the temperature-dependent association behavior of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)(PEO-PPO-PEO)block copolymers was investigated using pyrene fluorescence *** critical micellization temperature(CMT)of pluronics in aqueous solution was increased by the addition of BSA.A closed association model was used to obtain the standard free energies(△DG^(0)),enthalpies(△DH^(0)),and entropies(△DS^(0))of *** standard enthalpy and entropy of micellization for pluronic polymers in water were decreased with an increase of the BSA *** more PPO component in the pluronic polymer,the higher the changed values of micellization enthalpy and *** hydrophobic part of the pluronics,PPO,was responsible for the interaction between pluronics and *** interaction between PPO and BSA was correlated to the alternation of the PPO-PPO interaction by the addition of BSA,which would shift the CMT toward higher temperature and alter the thermodynamic parameters of micellization for pluronics in aqueous solutions.

关键词： block copolymer bovine serum albumin micelle fluorescence spectroscopy.

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Birdlike multisensory integrated oxide transistors for motion perception

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Nano Energy 2025年 140卷

作者： Zahid, Muhammad Gong, Jiaying Sadiq, Muhammad Irfan Wang, Jingwen Aslam, Fawad Jin, Chenxing Liu, Wanrong Xu, Yunchao Yang, Junliang Sun, Jia Hunan Key Laboratory for Super Microstructure and Ultrafast Process School of Physics Central South University Hunan Changsha410083 China Hunan Key Laboratory of Nanophotonics and Devices School of Physics Central South University 932 South Lushan Road Hunan Changsha410083 China State Key Laboratory of Precision Manufacturing for Extreme Service Performance College of Mechanical and Electrical Engineering Central South University Hunan Changsha410083 China State Key Laboratory of Transducer Technology Shanghai Institute of Microsystem and Information Technology 865 Changning Road Shanghai200050 China

Multisensory inputs have been observed to augment behavioral and neural responses in avian species, underscoring the importance of converging perceptual enhancement, cognitive function, and motion perception into a unified system. To address the need for neuromorphic devices that replicate this process, we present a bio-inspired neuromorphic system that integrates cognitive-vestibular sensory motion perception. The system leverages a multi-input device fabricated from an ion-gel-gated In2O3 transistor, which exhibits adaptive plasticity, stable modulation, and spatiotemporal integration. The system embodies efficacious multisensory integration by processing dual-modal motion signals as spike trains, assigning salience weights via mean-firing rates and postsynaptic currents. Validation experiments demonstrate the system's ability to recognize human activities and classify aircraft flight motion modes, aligning with biologically plausible principles of multisensory integration. This neuromorphic system has far-reaching implications for developing advanced sensory artificial devices, smart electronics, and interactive intelligent electronics. © 2025 Elsevier Ltd

关键词： Birds

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Stable and Efficient Perovskite Photovoltaics via a Three-In-One Passivating Approach by Aminoacetonitrile Hydrochloride

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Advanced Energy Materials 2025年第0期

作者： Liu, Yinjiang Kong, Tengfei Zhang, Yang Zhao, Zihan Chen, Weiting Liu, Wenli Gao, Peng Wang, Xu-Dong Bi, Dongqin State key laboratory of optoelectronic materials and technology Guangdong Provincial Key Laboratory of low carbon chemistry and process energy conservation School of Materials Science and Engineering Sun Yat-sen University Guangzhou510275 China Laboratory for Advanced Functional Materials Xiamen Institute of Rare Earth Materials Haixi Institute Chinese Academy of Sciences Xiamen361021 China Yanyang Energy Inc Xiamen361021 China MOE Key Laboratory of Bioinorganic and Synthetic Chemistry Lehn Institute of Functional Materials School of Chemistry Sun Yat-sen University Guangzhou510275 China

Reducing defect density is of significant importance for enhancing the power conversion efficiency (PCE) and stability of perovskite solar cells (PSCs). While most previous outstanding studies have focused on individual layers within the perovskite device structure. Herein, a three-in-one strategy using the aminoacetonitrile hydrochloride (AmiHCl) molecule to reduce the defects in the bulk and surface of perovskite. The results of the study found that the AmiHCl bottom modification can decrease the number of buried interface holes, doping into bulk perovskite can modulate crystallization via a strong interaction between AmiHCl and perovskite components, and the upper interface modification can inhibit the formation of vacancies by creating hydrogen bonds with A-site cations. This approach yields PSCs with an efficiency of 25.90% and a high fill factor (FF) of 88.54%. Additionally, the modified PSCs show significantly enhanced operational stability, with the PCE retaining more than 90.0% of the initial value after 1350 h of maximum power point tracking. © 2025 Wiley-VCH GmbH.

关键词： Perovskite

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Plasma-enhanced synthesis of nitrogen-doped silicon carbide nanopowders in a fluidized-bed reactor for lithium-ion battery anodes

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Chemical engineering Journal 2025年 514卷

作者： Wang, Zihao Lei, Zewei Hong, Ruoyu Li, Minglin He, Xianfeng College of Chemical Engineering Fuzhou University Fuzhou350108 China School of Mechanical Engineering and Automation Fuzhou University Fuzhou350108 China International Joint Laboratory on Intelligent Sensing and Robotics Fuzhou University Fuzhou China School of Chemical Engineering University of Chinese Academy of Sciences Beijing101408 China State Key Laboratory of Mesoscience and Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing100190 China

Ultrafine silicon carbide (SiC) powders have garnered increasing attention mainly due to their vast potential for diverse applications. In this study, a plasma-enhanced fluidized bed reactor to crack hexamethyldisilane (HMDS) was effectively developed, thereby producing SiC/NC composites with diameters ranging from 10 to 20 nm. This method enabled large-scale and sustainable production of SiC/NC composites. Concurrently, nitrogen doping was finally achieved by introducing ammonia during the plasma process, which increased material defects and thus enhanced electrical conductivity. Moreover, the abundant hydrogen atoms in ammonia modulated the product properties, as evidenced by reduced particle size, enhanced crystallinity as well as decreased free-carbon content. The synthesized composites were applied as anodes in lithium-ion batteries, and their feasibility was confirmed through extensive testing. Notably, SiC-150 exhibited a discharge capacity of 413mAh g−1 after 200 cycles at 0.1 A g−1 and maintained a high specific capacity of 780mAh g−1 even after 800 cycles at 0.5 A g−1. © 2025 Elsevier B.V.

关键词： Silicon carbide

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A Risk-Averse Just-In-Time Scheme for Learning-Based Operation of Microgrids With Coupled Electricity-Hydrogen-Ammonia Under Uncertainties

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IEEE Transactions on Sustainable Energy 2025年

作者： Li, Longyan Ning, Chao Pan, Guangsheng Zhang, Leiqi Gu, Wei Zhao, Liang Du, Wenli Shahidehpour, Mohammad Shanghai Jiao Tong University Department of Automation Shanghai200240 China Ministry of Education of China Key Laboratory of System Control and Information Processing Shanghai200240 China School of Electrical Engineering Southeast University Nanjing210096 China Zhejiang Key Laboratory of Distributed Generations and Microgrid Technology State Grid Zhejiang Electric Power Research Institute Hangzhou310014 China Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of Education East China University of Science and Technology China Department of Electrical and Computer Engineering Illinois Institute of Technology ChicagoIL60616 United States

This paper proposes a Risk-Averse Just-In-Time (RAJIT) operation scheme for Ammonia-Hydrogen-based Micro-Grids (AHMGs) to boost electricity-hydrogen-ammonia coupling under uncertainties. First, an off-grid AHMG model is developed, featuring a novel multi-mode ammonia synthesis process and a hydrogen-ammonia dual gas turbine with tunable feed-in ratios. Subsequently, a state-behavior mapping strategy linking hydrogen storage levels with the operation modes of ammonia synthesis is established to prevent cost-ineffective shutdowns. The proposed model substantially improves operational flexibility but results in a challenging nonlinear fractional program. Based upon this model, a data-driven RAJIT scheme is developed for the real-time rolling optimization of AHMGs. Unlike conventional one-size-fits-all schemes using one optimization method throughout, the data-driven RAJIT intelligently switches between cost-effective deterministic optimization and risk-averse online-learning distributionally robust optimization depending on actual risk profiles, thus capitalizing on the respective strengths of these two optimization methods. To facilitate the solution of the resulting nonlinear program, we develop an equivalent-reformulation-based solution methodology by leveraging a constraint-tightening technique. Numerical simulations demonstrate that the proposed scheme guarantees safety and yields an overall cost reduction up to 14.6% compared with several state-of-the-art methods. © 2025 IEEE.

关键词： Ammonia

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Effect of Mn(II) on quartz flotation using dodecylamine as collector

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Journal of Central South University 2014年第9期21卷 3603-3609页

作者：杨志超冯雅丽李浩然王维大滕青张旭 Civil and Environment Engineering School University of Science and TechnologyBeijing State Key Laboratory of Biochemical Engineering Institute of Process Engineering(Chinese Academy of Sciences)

Quartz is, in most cases, the major gangue mineral found in the manganese ore. Mn iron, dissolved from the surface of ore, will determine the interfacial properties of the particles and, thus, their flotation behavior. In this work, the effect of Mn2+ on quartz flotation was investigated through flotation tests. It was found that quartz can be depressed with Mn2+ and floated with dodecylamine in the pH region 7-8. In order to prove the validity of the findings, UV spectrophotometry, FTIR and SEM-EDS were carried out. UV spectrophotometry tests results show that Mn2+ can competitive adsorb with RNH3+ in the surface of quartz at acidic and neutral pH values. The FTIR measurements and SEM-EDS analysis indicate that Mn2+ forms precipitation and adsorbs on the negatively charged quartz surface, it induces quartz recovery dropping in alkaline pH. Furthermore, in the case of sodium hexametaphosphate(SH), sodium silicate or citric acid, the effects of Mn2+ were also studied. This depression in the given Mn2+ did not disappear. Citric acid is an appropriate modifier to separate quartz depressed by Mn2+ from other ores at pH 7.

关键词： flotation quartz Mn（II） dodecylamine

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Revealing global reaction mechanisms of polypropylene pyrolysis by reactive molecular dynamic simulation and reaction class prediction

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Polymer Degradation and Stability 2025年 239卷

作者： Li, Wenyao Zheng, Mo Li, Jiangang Ren, Chunxing Li, Xiaoxia College of New Materials and Chemical Engineering Beijing Institute of Petrochemical Technology Beijing 102617 China State Key Laboratory of Mesoscience and Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing100190 China Innovation Academy for Green Manufacture Chinese Academy of Sciences Beijing100190 China University of Chinese Academy of Sciences Beijing100049 China

Polypropylene (PP) pyrolysis offers a promising solution for transforming waste plastics into high-value chemicals. This work presents a combination approach of large-scale reactive molecular dynamic simulation (ReaxFF MD) and automatic reaction class prediction with machine learning method for investigating PP pyrolysis reaction mechanism. The reasonableness of the global reaction understanding on PP pyrolysis is supported by both the consistent representative pyrolyzate detections between experiments and simulation, as well as the same yield ranking of C3H6>C2H4>CH4>C2H6 at the initial decomposition dominant stage between experiments and simulations. The comprehension of the dynamic product profiles and their relevant reaction classes in polypropylene pyrolysis was revealed, which indicates that the major species distribution in PP pyrolysis detectable experimentally become explainable by the major reaction classes with the aid of automatic reaction classification approach of SRG-Reax, The dominant homolysis and β-scission reaction classes accounting for 30 %∼50 % in the initial PP pyrolysis corresponds to the rapid increasing yields of C2H4 and C3H6. The increasing reaction classes of ring opening & recombination and chain cyclization as well as of intra-molecular H-shift, H detachment and inter-molecular H-abstraction should be responsible for the increasing ring formation of 5-membered, 6-membered, 7-membered rings, particularly for formation of aryl rings and naphthalene with temperature. The formation pathways of benzene, naphthalene and anthracene were unraveled. The mechanism understanding of PP pyrolysis demonstrate the potential of the combined simulation strategy of large-scale simulation and reaction class prediction in deepening understanding polymer degradation mechanism. © 2025

关键词： Ring opening polymerization

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Trifluoroethanol-assisted asymmetric propargylic hydrazination to α-tertiary ethynylhydrazines enabled by sterically confined pyridinebisoxazolines

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Nature Communications 2025年第1期16卷 1-12页

作者： Gong, Yi Zhang, Zheng Liu, Huijuan Wang, Tao Jiang, Mengmeng Feng, Nan Peng, Peiying Wang, Huimin Zhou, Feng Wang, Xin Zhou, Jian State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular Engineering East China Normal University Shanghai 200062 China College of Chemistry Sichuan University Chengdu 610064 China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Shanghai 200032 China College of Chemistry and Molecular Sciences Henan University Kaifeng 475004 China

We report the highly enantioselective Cu-catalyzed asymmetric propargylic substitution (APS) of α-tertiary propargylic electrophiles using hydrazines and hydroxylamines as a fruitful strategy to access multifunctional α-tertiary hydrazines or hydroxylamines. Using trifluoroethanol (TFE) as the solvent play a key role to decrease the nucleophilicity of hydrazines to suppress side reactions such as elimination, thus improve the yield and the enantioselectivity. NMR analysis and theoretical calculations suggest the formation of an H-bond adduct of TFE with hydrazide, stabilized by multiple H-bonding interactions, including C–F···H–N interaction. The sterically confined pyridinebisoxzolines (PYBOX), featuring a bulky benzylthio shielding group also contribute to the excellent enantioselectivity. Aryl- and aliphatic-ketone-derived α-ethynylalcohol carbonates, α-tertiary α-ethynyl epoxides, cyclic carbonates and and α-hydroxycarboxylates all are competent substrates to afford α-tertiary α-ethynylhydrazines with high structural diversity. The obtained products can be readily converted into various α-tertiary hydrazines and azacycles featuring an aza-quaternary stereocenter. © The Author(s) 2025.

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