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Design of a Novel Multi-Layer Enzyme Membrane Reactor for Low-Fouling, Tailored Production of Oligodextran

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SSRN 2023年

作者： Pinelo, Manuel Su, Ziran Jankowska, Katarzyna Sigurdardóttir, Sigyn Björk Zhang, Wenjing Kaiser, Andreas Luo, Jianquan Process and Systems Engineering Centre Department of Chemical and Biochemical Engineering Technical University of Denmark Kgs Lyngby2800 Denmark Harbin Institute of Technology China Solid State Electrochemistry Department of Energy Conversion and Storage Technical University of Denmark Kgs Lyngby2800 Denmark State Key Laboratory of Biochemical Engineering Institute of Process Engineering University of Chinese Academy of Sciences Chinese Academy of Sciences Beijing100190 China

Controlling the molecular weight (Mw) of oligosaccharides in an enzymatic conversion process is a challenge in the production of intermediate-sized oligosaccharides. The enzymatic membrane reactor (EMR) with immobilized enzymes is proposed as a strategy to improve production of the intermediate-sized oligosaccharides. The immobilized enzymes catalyze reactions near the membrane surface, and the target molecules can be immediately separated from the enzymes once they reach the desired size. Hence, EMRs with immobilized enzymes enable better control on the product quality. However, immobilizing enzymes directly on the membrane surface usually causes inevitable membrane fouling and reduces the membrane separation performance. In this study, we proposed a novel configuration of EMR that contains a porous 3-D fibrous layer, that was produced via electrospinning, a porous mechanical support layer on top and a commercial separation membrane on the bottom. Polydopamine (PDA), tannic acid (TA) and (3-Aminopropyl) triethoxysilane (APTES) were firstly used to modify electrospun fibers to offer binding sites for enzyme immobilization. Then the enzymes were filtrated through the 3-layer structure for the immobilization. In comparison to the incubation-immobilized enzymes (produced 0.075 µmol-isomaltose/min), the ‘fouling-induced’ enzyme immobilization proposed here significantly increased the immobilized enzyme activity up to 11.5 µmol-isomaltose/min. Moreover, the extra layer on the membrane surface preserved the desired catalytic pattern of the enzymes, and reduced membrane fouling caused by the enzymes, and thus the membrane preserved high selectivity towards the oligosaccharides products. In the production of low Mw oligosaccharides, due to the high enzyme activity (up to 11.3 µmol-isomaltose per minute) on the catalytic layer and excellent selectivity of the membrane, stable Mw of oligosaccharides were obtained, which indicates a successful high-performance EMR. Different s

关键词： Membranes

Protocol for hydroxylating aryl chlorides catalyzed by photouranium with water under ambient conditions

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STAR Protocols 2024年第4期5卷 103279页

作者： Li, Chengliang Bai, Leiyang Jiang, Xuefeng Hainan Institute of East China Normal University State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical Process School of Chemistry and Molecular Engineering East China Normal University 3663 North Zhongshan Road Shanghai 200062 China School of Chemistry and Chemical Engineering Henan Normal University Henan Xinxiang 453007 China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 China

Here, we present a protocol for the hydroxylation of aryl chlorides catalyzed by photouranium with water under ambient conditions. We describe steps for gram-scale hydroxylation of 2′-chloroacetophenone using our self-designed continuous-flow photoreactor. We then detail procedures for obtaining 2′-hydroxyacetophenone using our self-designed rapid separation and purification instrument. This protocol is not suitable for polycyclic and heterocyclic aryl chlorides. For complete details on the use and execution of this protocol, please refer to Sun et al.¹ © 2024 The Author(s)

关键词： Chemistry Environmental sciences

Three-dimensional MXenes heterostructures and their applications

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Science China Materials 2022年第11期65卷 2895-2910页

作者： Jizhou Jiang Fangyi Li Jing Zou Song Liu Jiamei Wang Yilun Zou Kun Xiang Han Zhang Guoyin Zhu Yizhou Zhang Xianzhu Fu Jyh-Ping Hsu School of Environmental Ecology and Biological Engineering School of Chemistry and Environmental EngineeringKey Laboratory of Green Chemical Engineering Process of Ministry of EducationEngineering Research Center of Phosphorus Resources Development and Utilization of Ministry of EducationWuhan Institute of TechnologyWuhan 430205 Key Laboratory of Rare Mineral Ministry of Natural ResourcesGeological Experimental Testing Center of Hubei ProvinceWuhan 430034 Institute of Chemical Biology and Nanomedicine(ICBN) State Key Laboratory of Chemo/Biosensing and ChemometricsCollege of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082 College of Materials Science and Engineering Shenzhen Engineering Laboratory of Phosphorene and Optoelectronics and Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong ProvinceShenzhen UniversityShenzhen 518060 Institute of Advanced Materials and Flexible Electronics(IAMFE) School of Chemistry and Materials ScienceNanjing University of Information Science&TechnologyNanjing 210044 Department of Chemical Engineering “National”Taiwan UniversityTaipei 10617

Due to their unique surface chemistry,highly adjustable metal components,hydrophilicity,and high carrier concentrations,MXenes are applied in a variety of *** to other two-dimensional(2D)materials,building heterostructures with additional materials to form a 3D porous architecture for MXenes can significantly enhance their functionality and ***,the open structures and well-defined pathways of these 3D structured MXenes can improve ionic and electronic transport,thereby promoting their applications in electrochemical energy storage,sensing,catalysis,and *** this review,the recent efforts made on preparing 3D porous MXenes with heterostructures,focusing on MXenes/C,MXenes/inorganics,and MXenes/polymers were *** discussion covers aspects ranging from the design to synthesis of 3D porous MXenes,and their applications in photocatalysis,environmental monitoring and electrochemical energy *** review is concluded by presenting the prospects and insights on exploring the relationships between the porosity formation mechanisms,properties and applications of the 3D porous MXenes *** review can provide meaningful guidance for the design,fabrication and application of 3D porous MXenes in high-performance materials and devices.

关键词： 3D porous MXenes MXenes heterostructures photocatalysis environmental monitoring electrochemical energy storage

Transfer Learning across Different Chemical Domains: Virtual Screening of Organic Materials with Deep Learning Models Pretrained on Small Molecule and Chemical Reaction Data

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arXiv

arXiv 2023年

作者： Zhang, Chengwei Zhai, Yushuang Gong, Ziyang Duan, Hongliang She, Yuan-Bin Yang, Yun-Fang Su, An State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology Key Laboratory of Green Chemistry-Synthesis Technology of Zhejiang Province College of Chemical Engineering Zhejiang University of Technology Zhejiang Hangzhou310014 China Key Laboratory of Pharmaceutical Engineering of Zhejiang Province National Engineering Research Center for Process Development of Active Pharmaceutical Ingredients Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals Zhejiang University of Technology Hangzhou310014 China Faculty of Applied Sciences Macao Polytechnic University 999078 China

Machine learning is becoming a preferred method for the virtual screening of organic materials due to its cost-effectiveness over traditional computationally demanding techniques. However, the scarcity of labeled data for organic materials poses a significant challenge for training advanced machine learning models. This study showcases the potential of utilizing databases of drug-like small molecules and chemical reactions to pretrain the BERT model, enhancing its performance in the virtual screening of organic materials. By fine-tuning the BERT models with data from five virtual screening tasks, the version pretrained with the USPTO-SMILES dataset achieved R2 scores exceeding 0.94 for three tasks and over 0.81 for two others. This performance surpasses that of models pretrained on the small molecule or organic materials databases and outperforms three traditional machine learning models trained directly on virtual screening data. The success of the USPTO-SMILES pretrained BERT model can be attributed to the diverse array of organic building blocks in the USPTO database, offering a broader exploration of the chemical space. The study further suggests that accessing a reaction database with a wider range of reactions than the USPTO could further enhance model performance. Overall, this research validates the feasibility of applying transfer learning across different chemical domains for the efficient virtual screening of organic materials. © 2023, CC BY-NC-SA.

关键词： Chemical reactions

Combination of Surfactants and Enzyme Cocktails for Enhancing Woody Biomass Saccharification and Bioethanol Production from Lab-Scale to Pilot-Scale

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SSRN 2023年

作者： Qi, Wei Feng, Qifa Wang, Wen Zhang, Yu Hu, Yuzhen Shakeel, Usama Xiao, Lin Wang, Lan Chen, Hongzhang Liang, Cuiyi Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development Guangzhou510640 China University of Chinese Academy of Sciences Beijing100049 China Longlive Bio-technology Co. Ltd. Shandong Province Yucheng251200 China State Key Laboratory of Biochemical Engineering Beijing Key Laboratory of Biomass Refining Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing100190 China

Converting woody biomass to bioethanol might be more affordable, environmentally friendly, and efficient for making biofuel commercially feasible, but it would still need a significant optimization process and expand pilot-scale research. A combination of commercial low enzymes loading at 10 FPU/g glucan and compound additives utilizing Tween 80 (TW), PEG8000 (PEG), and sophorolipid (SL) applied from lab-scale to pilot-scale have been studied in this work at economically viable dosages for enhancing bioethanol production. In lab-scale saccharification and fermentation (SHF), pretreated poplar at a high solid loading of 20% yielded the highest ethanol titers of 30.96 g/L and theoretical ethanol yield of 92.79%. Additionally, pilot-scale running was used to investigate the bioethanol enlargement case, a final volume of 33 m3 which yielded the greatest ethanol amount of 599.61 kg from poplar wood while gaining on-site value-added production of hemicellulosic and cellobiose liquor 1121.91 kg and lignin residues 2292.54 kg. © 2023, The Authors. All rights reserved.

关键词： Surface active agents

Electrocatalytic ammonia synthesis catalyzed by mesoporous nickel oxide nanosheets loaded with Pt nanoparticles

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Chinese Journal of Catalysis 2022年第5期43卷 1371-1378页

作者： Wei Xiong Min Zhou Hao Li Zhao Ding Da Zhang Yaokang Lv Key Laboratory for Green Chemical Process(Ministry of Education) Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of EducationHubei Key Laboratory Of Novel Reactor&Green Chemical TechnologySchool of Chemistry and Environmental EngineeringWuhan Institute of TechnologyWuhan 430205HubeiChina Department of Physics Technical University of DenmarkLyngby 2800Denmark The State Key Laboratory of Refractories and Metallurgy Institute of Advanced Materials and NanotechnologyWuhan University of Science and TechnologyWuhan 430071HubeiChina Changjiang River Scientific Research Institute Wuhan 430071HubeiChina College of Chemical Engineering Zhejiang University of TechnologyHangzhou 310014ZhejiangChina

Owing to its cost‐effectiveness and adjustable eight‐electron distribution in the 3d orbital,nickel oxide(NiO)is considered an effective electrocatalyst for an ambient electrochemical nitrogen reduction reaction(NRR).However,because of the low conductivity of the transition metal oxide electrocatalyst,its application in this field is *** this study,we found that the doping of NiO nanosheets with a small amount(3–10 nm)of Pt nanoparticles(Pt/NiO‐NSs)leads to considerable improvements in the Faradaic efficiency(FE)and NH_(3) yield compared with those obtained using pure NiO,breaking the common perception that commercial Pt‐based electrocatalysts demonstrate little potential for NRR due to their high hydrogen evolution *** a 0.1 mol/L Na_(2)SO_(4) solution at−0.2 V ***,a typical Pt/NiO‐2 sample exhibits an optimum electrochemical NH_(3) yield of 20.59μg h^(–1)mg^(–1)*** an FE of 15.56%,which are approximately 5 and 3 times greater,respectively,than those of pure NiO nanosheets at the same applied potential.X‐ray photoelectron spectroscopy analysis revealed that Pt in Pt/NiO‐NSs exist as Pt0,Pt^(2+),and Pt^(4+)and that high‐valence Pt ions are more electropositive,thereby favoring chemisorption and the activation of N2 *** function theory calculations showed that the d‐band of Pt nanoparticles supported on NiO is significantly tuned compared to that of pure Pt,affording a more favorable electronic structure for *** results of this study show that Pt can be an effective NRR electrochemical catalyst when loaded on an appropriate *** importantly,it provides a new synthetic avenue for the fabrication of highly active Pt‐based NRR electrocatalysts.

关键词： Platinum nanoparticles NiO nanosheets Nitrogen reduction reaction Electrocatalysis

Electrosynthesis of Nitriles from Nitrate and Aldehyde Via C≡N Bond Construction

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SSRN 2025年

作者： Xue, Cheng Jia, Shuaiqiang Jiao, Jiapeng Chen, Xiao Dong, Mengke Xia, Zhanghui Deng, Ting Cheng, Hailian Chen, Chunjun Wu, Haihong He, Mingyuan Han, Buxing Shanghai Key Laboratory of Green Chemistry and Chemical Processes State Key Laboratory of Petroleum Molecular & Process Engineering School of Chemistry and Molecular Engineering East China Normal University Shanghai200062 China Institute of Eco-Chongming 20 Cuiniao Road Chenjia Town Chongming District Shanghai202162 China Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Colloid and Interface Thermodynamics Center for Carbon Neutral Chemistry CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing100190 China

Electrocatalytic nitrate reduction offers a promising approach to synthesizing valuable organic nitrogen compounds via C‒N coupling, serving as a pivotal solution to the pressing nitrate pollution issue. While significant progress has been made in electrosynthesizing C‒N and C=N compounds, the electrosynthesis of nitriles with C ≡ N bonds remains challenging, and has not been reported. Herein, we introduce a novel method for efficient synthesizing nitriles through electrocatalytic coupling of nitrate ions (NO3‒) with aldehydes under ambient conditions, employing ZnO/Sn/SnO2 as electrocatalyst. In situ spectroscopic characterization and theoretical calculations demonstrated that the adsorption and accumulation of *NH2OH and *RCHO on the catalyst plays a central role efficient reaction. The key C‒N bond-forming step is found to be the formation of hydroxylamine from nitrate reduction and its subsequent condensation with *RCHO. The C‒N coupling strategy can be applied to the synthesis of fatty nitrile and (hetero)aromatic nitrile compounds. This study opens the way for nitriles electrosynthesis from nitrogen wastes, which could contribute to utilization of nitrogen ***;Nitrate Reduction;C≡N Bond;Nitrile;Hydroxylamine © 2025, The Authors. All rights reserved.

关键词： Nitrates

Bioinspired Coating of Corn Straw with Polyethyleneimine-Tannic for Surfactants Removal from Aqueous Solution

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SSRN 2022年

作者： Li, Yun He, Zhiqin Qi, Benkun Chinese Research Academy of Environmental Sciences Beijing100012 China State Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing100190 China

In this study, bioinspired polyethyleneimine-tannic acid (PEI-TA) complexes were innovatively used for coating of corn straw (CS). The as-prepared PEI-TA modified CS (PEI-TA@CS) was applied to adsorptive removal of surfactants from aqueous solution. With anionic surfactant sodium dodecylbenzene sulfonate (SDBS) as the target pollutant, the effects of solution pH, contact time, initial concentration, adsorbent dosage, and temperature on the adsorption of SDBS on PEI-TA@CS were investigated. The results showed that the adsorption reached equilibrium in about 3 h and the kinetic data were well consistent with the pseudo-second-order model. Freundlich model was found to fit the isotherms result better, which suggested that the adsorption of SDBS onto PEI-TA@CS was mainly a heterogeneous adsorption process. Thermodynamic parameters indicated that the nature of the adsorption was exothermic and spontaneous under the tested experimental conditions. The mechanisms involved in the adsorption of SDBS by PEI-TA@CS mainly include electrostatic interactions, hydrophobic interactions, and π-π interactions. The PEI-TA@CS could remove 94.95% of SDBS from aqueous solution of SDBS (50 mg/L) with the use of an adsorbent dosage of 100 mg. Even in the complex synthetic greywater, the removal of SDBS still reached as high as 81.99%. The overall results indicated that PEI-TA@CS has promising applications in the removal of anionic surfactants from greywater © 2022, The Authors. All rights reserved.

关键词： Adsorption

SaleNet: A low-power end-to-end CNN accelerator for sustained attention level evaluation using EEG

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arXiv

arXiv 2022年

作者： Zhang, Chao Tang, Zijian Guo, Taoming Lei, Jiaxin Xiao, Jiaxin Wang, Anhe Bai, Shuo Zhang, Milin Department of Electronic Engineering Tsinghua University China Institute for Precision Medicine Tsinghua University China State Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences China

This paper proposes SaleNet - an end-to-end convolutional neural network (CNN) for sustained attention level evaluation using prefrontal electroencephalogram (EEG). A bias-driven pruning method is proposed together with group convolution, global average pooling (GAP), near-zero pruning, weight clustering and quantization for the model compression, achieving a total compression ratio of 183.11x. The compressed SaleNet obtains a state-of-the-art subject-independent sustained attention level classification accuracy of 84.2% on the recorded 6-subject EEG database in this work. The SaleNet is implemented on a Artix-7 FPGA with a competitive power consumption of 0.11 W and an energy-efficiency of 8.19 GOps/W. Copyright © 2022, The Authors. All rights reserved.

关键词： Convolutional neural networks