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Mechanism of ethanol/water reverse separation through a functional graphene membrane:a molecular simulation investigation

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Frontiers of Chemical Science and Engineering 2023年第3期17卷 347-357页

作者： Quan liu Xian Wang Yanan guo Gongping liu kai-Ge Zhou School of Chemical Engineering Analytical and Testing CenterAnhui University of Science and TechnologyHuainan 232001China State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Reverse-selective membranes have attracted considerable interest for bioethanol ***,to date,the reverse-separation performance of ethanol/water is poor and the separation mechanism is ***-based membranes with tunable apertures and functional groups have shown substantial potential for use in molecular *** molecular dynamics simulations,for the first time,we reveal twoway selectivity in ethanol/water separation through functional graphene *** graphene(PG)exhibits reverse-selective behavior with higher ethanol fluxes than water,resulting from the preferential adsorption for *** flow mappings show that this ethanol-permselective process is initiated by the presence of ethanol-enriched and water-barren pores;this has not been reported in previous *** contrast,water molecules are preferred for hydroxylated graphene membranes because of the synergistic effects of molecular sieving and functional-group attraction.A simulation of the operando condition shows that the PG membrane with an aperture size of 3.8Åachieves good separation performance,with an ethanol/water separation factor of 34 and a flux value of 69.3 kg∙m‒2∙h‒1∙bar‒*** study provides new insights into the reverse-selective mechanism of porous graphene membranes and a new avenue for efficient biofuel production.

关键词： reverse separation graphene membrane ethanol/water separation molecular simulation

Role of the Greenland Sea ice anomaly in the late-spring drought over Northwest China

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 1-5页

作者： Yang liu Huopo Chen Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of SciencesBeijingChina Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University for Information Science and TechnologyNanjingChina

Drought across Northwest China in late spring has exerted a vital effect on the local climate and agricultural production,and has been alleviated during the past *** study explored the influence of the preceding Arctic sea ice on the May drought in Northwest China caused by the precipitation *** analysis indicated that when the Greenland Sea ice concentration is abnormally high during February to April,the dry conditions in Northwest China tend to be *** increase of sea ice in the Greenland Sea can excite a meridional circulation,which causes sea surface temperature(SST)anomalies in the North Atlantic via the sea-air interaction,manifested as significant warm SST anomalies over the south of Greenland and the subtropical North Atlantic,but negative SST anomalies over the west of the *** abnormal SST pattern maintains to May and triggers a zonal wave train from the North Atlantic through Scandinavia and Central Asia to Northwest China,leading to abnormal cyclones in Northwest ***,Northwest China experiences a more humid climate than usual.

关键词： Arctic sea ice Greenland Sea North Atlantic SST Drought Northwest China

Assessment of two different optimization principles applied in heat conduction

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Science Bulletin 2015年第23期60卷 2041-2053页

作者： Wenzhe Qi kai guo Hui liu Botan liu Chunjiang liu School of Chemical Engineering and Technology State Key Laboratory of Chemical Engineering Tianjin University Collaborative Innovation Center of Chemical Science and Engineering Tianjin University

Optimization principles play a crucial role in the intensification of the heat-transfer process. In this study, we assess and compare two principles, i.e., the entransy dissipation extremum(EDE) principle and the minimum entropy generation(MEG) principle, used in a typical ‘‘area to point’’ heat conduction problem solved via a cellular automaton algorithm. The simulated results indicate that both rules can ameliorate the tree-network conductive path, leading to a more uniform thermal field and lower average and maximum temperatures. In contrast to the MEG principle, the EDE principle is more appropriate to be linked to the algorithm when dealing with the‘‘area to point’’ heat conduction optimization, especially with a higher conductivity ratio, kp/k0, between the high conductivity material and the low conductivity material and the fraction of high conductivity, /0. With the analysis of total entransy dissipation rate and entropy generation of the domain optimized by two principles, the results indicate that the EDE principle is more suitable for the heattransfer processes without heat–work conversion. Moreover, optimization via reducing the total entransy dissipation rate exhibits better performance in decreasing the equivalent resistance theoretically.

关键词： Heat conduction Entransy dissipation Entropy generation Optimization principle Cellular automaton

Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy Chemistry 2025年第1期100卷 458-468页

作者： Peng Zhu Cun liu Yiren Yu guoshu Gao Yumeng Zhao Xiongfu Zhang guodong liu guohui Yang State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： MFI zeolite ZSM-5 Nanosheets Scale-up synthesis Aromatic alkylation

Investigation of mass transfer model of CO_(2) absorption with Rayleigh convection using multi-relaxation time lattice Boltzmann method

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Chinese Journal of Chemical Engineering 2022年第10期50卷 130-142页

作者： Longyun Zheng kai guo Hongwei Cai Bo Zhang Hui liu Chunjiang liu School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China State Key Laboratory of Chemical Engineering Tianjin UniversityTianjin 300072Chin

CO_(2) absorption into absorbents is a widely used method to reduce carbon emissions,in which the concentration gradient near the gas-liquid interface may induce Rayleigh convection(RC).Once RC occurs,the mass transfer rate will be significantly ***,it is necessary to explore the mass transfer enhancement mechanism further and develop a penetration/surface divergence hybrid mass transfer *** this study,we conduct research on the process of CO_(2) absorption into ethanol with ***,we use a multi-relaxation time lattice Boltzmann method to simulate the absorption process and obtain the flow and concentration *** we also verify the reliability of the numerical simulation results by comparing with the experimental ***,we analyze the characteristics of non-uniform flow and concentration fields in ***,we divide the near-interface region into diffusion-dominated and convection-dominated mass transfer zones by checking whether the horizontal average velocity is greater than 1.0×10^(-4) m·s^(-1).Furthermore,based on the differences in mass transfer mechanisms of the aforementioned two zones,we propose a penetration/surface divergence hybrid model to predict the instantaneous mass transfer *** prediction results demonstrate that the hybrid model can precisely predict the instantaneous mass transfer coefficient of the entire CO_(2) absorption *** proposed hybrid model provides a promising way to deal with the complex mass transfer problems with non-uniform flow and concentration fields.

关键词： Carbon dioxide Absorption Rayleigh convection Numerical simulation multiple-relaxation-time orgeneralized lattice Boltzmannmodel(MRT-LBM) Mass transfer

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高速碰撞诱发闪光辐射温度的测量及误差分析

发光学报 2018年第5期39卷 653-660页

作者：韩雅菲唐恩凌贺丽萍王猛郭凯夏瑾刘淑华马建军王睿智李振波沈阳理工大学装备工程学院辽宁沈阳110159

为实现对高速碰撞诱发的闪光辐射温度进行实验测量及误差分析,建立了二级轻气炮加载系统及闪光辐射温度测量系统。采用聚碳酸酯弹丸分别以6 km/s、3.9 km/s的速度垂直撞击2A12铝靶,利用瞬态光纤高温计采集闪光信号,通过比色法计算不同... 详细信息

为实现对高速碰撞诱发的闪光辐射温度进行实验测量及误差分析,建立了二级轻气炮加载系统及闪光辐射温度测量系统。采用聚碳酸酯弹丸分别以6 km/s、3.9 km/s的速度垂直撞击2A12铝靶,利用瞬态光纤高温计采集闪光信号,通过比色法计算不同碰撞条件下的闪光辐射强度及辐射温度。依据普朗克辐射定律计算了不同波长及温度条件下的闪光辐射强度理论值,与实验测量结果相比较并进行了误差分析;分别采用双色测温法的不同波长组合及四色测温法计算了闪光辐射温度及其平均温度,通过计算标准差分析了波长的选取对闪光辐射温度的影响。结果表明:与理论计算结果相比较,实验测量得到的闪光辐射强度值偏低,采用双色测温法计算闪光辐射温度时波长的选取对计算结果影响很大,波长间隔越大计算结果误差越小(误差最小值实验No.1为68.25 K,实验No.2为30.67 K);四色测温法计算得到的闪光辐射温度与平均温度相近(误差实验No.1为72.88 K,实验No.2为63.66 K),因此采用比色法计算闪光辐射温度时应尽量选取大间隔波长或多个波长参与计算以降低误差。

关键词：高速碰撞闪光辐射强度闪光辐射温度瞬态光纤高温计误差分析

Defects‑Rich Heterostructures Trigger Strong Polarization Coupling in Sulfides/Carbon Composites with Robust Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 528-547页

作者： Jiaolong liu Siyu Zhang Dan Qu Xuejiao Zhou Moxuan Yin Chenxuan Wang Xuelin Zhang Sichen Li Peijun Zhang Yuqi Zhou kai Tao Mengyang Li Bing Wei Hongjing Wu Mengyang Li Bing Wei Hongjing Wu School of Physics Xidian UniversityXi’an 710071People’s Republic of China School of Advanced Materials and Nanotechnology State Key Discipline Laboratory of Wide Band Gap Semiconductor TechnologyXidian UniversityXi’an 710071People’s Republic of China School of Microelectronics Xidian UniversityXi’an 710071People’s Republic of China School of Telecommunication Engineering Xidian UniversityXi’an 710071People’s Republic of China MOE Key Laboratory of Material Physics and Chemistry Under Extraordinary School of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China The Ministry of Education Key Laboratory of Micro and Nano Systems forAerospace School of Mechanical EngineeringNorthwestern PolytechnicalUniversityXi’an 710072People’s Republic of China

Defects-rich heterointerfaces integrated with adjustable crystalline phases and atom vacancies,as well as veiled dielectric-responsive character,are instrumental in electromagnetic *** methods,however,constrain their delicate ***,an innovative alternative is proposed:carrageenan-assistant cations-regulated(CACR)strategy,which induces a series of sulfides nanoparticles rooted in situ on the surface of carbon *** unique configuration originates from strategic vacancy formation energy of sulfides and strong sulfides-carbon support interaction,benefiting the delicate construction of defects-rich heterostructures in M_(x)S_(y)/carbon composites(M-CAs).Impressively,these generated sulfur vacancies are firstly found to strengthen electron accumulation/consumption ability at heterointerfaces and,simultaneously,induct local asymmetry of electronic structure to evoke large dipole moment,ultimately leading to polarization coupling,i.e.,defect-type interfacial ***“Janus effect”(Janus effect means versatility,as in the Greek two-headed Janus)of interfacial sulfur vacancies is intuitively confirmed by both theoretical and experimental investigations for the first ***,the sulfur vacancies-rich heterostructured Co/Ni-CAs displays broad absorption bandwidth of 6.76 GHz at only 1.8 mm,compared to sulfur vacancies-free CAs without any dielectric *** defects-rich heterostructures,this one-pot CACR strategy may steer the design and development of advanced nanomaterials,boosting functionality across diverse application domains beyond electromagnetic response.

关键词： Defects-rich heterointerfaces Sulfides Polarization coupling Electromagnetic wave absorption

Advances in flexible organic field-effect transistors and their applications for flexible electronics

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npj Flexible Electronics 2022年第1期6卷 1-19页

作者： kai liu Bang Ouyang Xiaojun guo Yunlong guo Yunqi liu Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of Sciences100190 BeijingPeople’s Republic of China School of Chemical Sciences University of Chinese Academy of Sciences100049 BeijingPeople’s Republic of China Department of Electronic Engineering School of Electronic Information and Electrical EngineeringShanghai Jiao Tong University200240 ShanghaiPeople’s Republic of China

Flexible electronics have suggested tremendous potential to shape human lives for more convenience and *** efforts have been devoted to developing flexible organic field-effect transistor(FOFET)technologies for rollable displays,bendable smart cards,flexible sensors and artificial ***,these applications are still in a nascent stage for lack of standard highperformance material stacks as well as mature manufacturing *** this review,the material choice and device design for FOFET devices and circuits,as well as the demonstrated applications are summarized in ***,the technical challenges and potential applications of FOFETs in the future are discussed.

关键词： effect field devoted

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改性秸秆纤维对水泥砂浆韧性的影响研究

工程建设与设计 2017年第2期 72-74页

作者：胡洁琼赵国栋刘开平刘竞怡陕西省高速公路建设集团公司西安710065 黄河中上游管理局西安710021 长安大学材料科学与工程学院西安710064

以麦秸秆纤维和PVA(聚乙烯醇)为水泥砂浆的改性剂,研究了其对混凝土韧性的影响。结果表明,掺加麦秸秆纤维及PVA可以提高水泥混凝土的韧性。在单掺2.5%纤维或单掺0.38%PVA的情况下,水泥砂浆的压/折强度比分别较基准试件降低13.6%和11.9%... 详细信息

以麦秸秆纤维和PVA(聚乙烯醇)为水泥砂浆的改性剂,研究了其对混凝土韧性的影响。结果表明,掺加麦秸秆纤维及PVA可以提高水泥混凝土的韧性。在单掺2.5%纤维或单掺0.38%PVA的情况下,水泥砂浆的压/折强度比分别较基准试件降低13.6%和11.9%。在复掺的情况下,麦秸杆纤维最佳用量为水泥量的1.5%,PVA最佳用量为纤维量的12.5%,此时,其压/折比的期望值为4.5,较普通水泥砂浆的降低23.7%。麦秸杆纤维和PVA共混掺入法较预涂掺入法好。掺加PVA使麦秸杆纤维与水泥混凝土之间的黏结力增强,有利于纤维对混凝土的增强增韧作用的发挥。

关键词：麦秸秆纤维 PVA 水泥砂浆韧性