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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

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

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

Analog spatiotemporal feature extraction for cognitive radio-frequency sensing with integrated photonics

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Light(Science & Applications) 2024年第3期13卷 478-487页

作者： Shaofu Xu Binshuo Liu Sicheng yi Jing Wang Weiwen zou State Key Laboratory of Advanced Optical Communication Systems and Networks Intelligent Microwave Lightwave Integration Innovation Center(imLic)Department of Electronic EngineeringShanghai Jiao Tong UniversityShanghaiChina

Analog feature extraction(AFE)is an appealing strategy for low-latency and efficient cognitive sensing systems since key features are much sparser than the Nyquist-sampled ***,applying AFE to broadband radio-frequency(RF)scenarios is challenging due to the bandwidth and programmability bottlenecks of analog electronic ***,we introduce a photonics-based scheme that extracts spatiotemporal features from broadband RF signals in the analog *** feature extractor structure inspired by convolutional neural networks is implemented on integrated photonic circuits to process RF signals from multiple antennas,extracting valid features from both temporal and spatial *** of the tunability of the photonic devices,the photonic spatiotemporal feature extractor is trainable,which enhances the validity of the extracted ***,a digital-analog-hybrid transfer learning method is proposed for the effective and low-cost training of the photonic feature *** validate our scheme,we demonstrate a radar target recognition task with a 4-GHz instantaneous *** results indicate that the photonic analog feature extractor tackles broadband RF signals and reduces the sampling rate of analog-to-digital converters to 1/4 of the Nyquist sampling while maintaining a high target recognition accuracy of 97.5%.Our scheme offers a promising path for exploiting the AFE strategy in the realm of cognitive RF sensing,with the potential to contribute to the efficient signal processing involved in applications such as autonomous driving,robotics,and smart factories.

关键词： scheme driving smart

Micro-nanoarchitectonic of aluminum-hydrogel propellant with static stability and dynamic rheology

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 87-96页

作者： Huiyan Guo Huaiyu Li Hongzhi Zhang lun Pan Chengxiang Shi Kang Xue Xiangwen Zhang Ji-Jun zou Key Laboratory for Advanced Fuel and Propellant of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

The aluminum-water system is a promising propellant due to high energy and low signal characteristics,and the gel form is easier to store and *** this work,hydrogels of water and aluminum particles were prepared using the low-molecular-weight gellant *** various physical properties of gel systems,including the water loss rate,phase transition temperature,and centrifugal stability at different gellant and aluminum contents,were *** properties were assessed through shear thinning tests,thixotropy tests,strain sweep analysis,and frequency sweep *** microstructure of the gel was obtained through scanning electron microscopy *** results show that the aluminum-hydrogel network structure is composed of micron-scale aluminum and agarose nanosheets,and the unique micro-nanostructure endows the gel with excellent mechanical strength and thermal stability,which improve with increasing gellant and aluminum ***,the gel with 2% agarose and 20% aluminum had the best performance;the storage modulus reached 90647 Pa,which was within the linear viscoelastic region,and the maximum withstand pressure was 111.2 kPa,which was 118.8% greater than that of the pure ***,the gel demonstrates remarkable shear thinning behavior and can undergo gel-sol transformation upon shearing or heating to exceeding 114℃.

关键词： aluminum-water propellant gelled propellant rheological property mechanical strength

A novel treatment of refractory coronary embolism:thrombus aspiration catheter-assisted twisting wire technique

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Journal of Geriatric Cardiology 2020年第2期17卷 110-115页

作者： yi-lun zou Jian-Qiang LI Yong-Tai GONG Dang-Hui SUN Yue LI Department of Cardiology the First Affiliated Hospital of Harbin Medical University

Coronary embolism caused by the thrombus from guiding catheters is a rare and challenging complication,which may result in serious and fatal consequences due to the loss of blood flow of the coronary artery during percutaneous coronary intervention(PCI).Current strategies for the reduction of thrombus burden include pharmacological agents(typically glycoprotein IIb/IIIa platelet inhibitors),embolic protection devices(filters and distal balloon occlusion with aspiration),mechanical thrombectomy and manual or aspiration thrombectomy devices.[1]The above strategies are widely used as the first-line treatments,but have limitations for some refractory thrombus.A few techniques have been invented before to address this issue,[2–6]but they are not always effective or unavailable in some medical centers.

关键词： Complication Percutaneous coronary intervention Refractory thrombus embolism Thrombectomy

Fabrication of surface passivated two-dimensional MFI zeolite for alkylation between toluene with methanol

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 115-124页

作者： Zhenyuan zou Shengzhi Gan Ting Pu Xingxing Zeng yi Huang Baoyu Liu School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006China School of Engineering Institute for Materials&Processesthe University of EdinburghEdinburgh EH93FBUnited Kingdom

The fabrication of suitable MFI zeolites to effectively produce para-xylene through the alkylation between toluene and methanol is highly ***,the two-dimensional pillared MFI zeolite was modified by silicalite-1,and its morphology and structure were systematically investigated by tuning the concentration of Si species during the secondary crystallization *** MFI zeolites were characterized by X-ray diffraction,transmission electron microscopy,pyridine-infrared and N_(2) adsorption-desorption *** characterization results showed that the external Brønsted acid sites of surface passivated P-MFI-x samples have been successfully ***,the P-MFI-23 showed long lifetime and high selectivity of para-xylene(about 35%)based on the cooperation between opened interlamellar structure and passivated silicalite-1 *** was found that the accumulated hard coke in the interior of MFI zeolites not only blocked the channels of zeolites but also covered the acidic sites,resulting in the deactivation of ***,the highest selectivity of para-xylene(about 48%)can be achieved for P-MFI-30 under harsh reaction condition,which also exhibited excellent regeneration property in the alkylation reaction between toluene and *** strategy described in present research may open a window for the design of other advanced materials.

关键词： alkylation MFI nanosheets catalysis

Effect of cis/trans molecular structures on pyrolysis performance and heat sink of decalin isomers

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Frontiers of Chemical Science and Engineering 2024年第1期18卷 51-60页

作者： Qing Liu Kang Xue Tinghao Jia Zhouyang Shen Zehao Han lun Pan Ji-Jun zou Xiangwen Zhang 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

Decalin is considered as an important compound of high-energy-density endothermic fuel,which is an ideal on-board coolant for thermal management of advanced ***,decalin contains two isomers with a tunable composition,and their effects on the pyrolysis performance,such as the heat sink and coking tendency have not been ***,we investigated the pyrolysis of decalin isomers,i.e.,cis-decalin,trans-decalin and their mixtures(denoted as mix-decalin),in order to clarify the effects of the cis-/trans-structures on the pyrolysis performance of decalin *** pyrolysis results confirmed that conversion of the tested fuels(600–725℃,4 MPa)decreased in the order cis-decalin>mix-decalin>*** analyses of the pyrolysis products were used to compare the product distributions from cis-decalin,mix-decalin and trans-decalin,and the yields of some typical components(such as cyclohexene,1-methylcyclohexene,benzene and toluene)showed significant differences,which could be ascribed to deeper cracking of ***,the heat sinks and coking tendencies of the decalins decreased in the order cis-decalin>mix-decalin>*** work demonstrates the relationship between the cis/trans structures and the pyrolysis performance of decalin,which provides a better understanding of the structure-activity relationships of endothermic hydrocarbon fuels.

关键词： endothermic fuel decalin pyrolysis heat sink molecular structure

Numerical manifold method for thermo-mechanical coupling simulation of fractured rock mass

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 1977-1992页

作者： Jiawei Liang Defu Tong Fei Tan Xiongwei yi Junpeng zou Jiahe Lv Faculty of Engineering China University of GeosciencesWuhan430074China Department of Civil Engineering Monash UniversityClaytonVIC3800Australia Badong National Observation and Research Station of Geohazards China University of GeoscienceWuhan430074China

As a calculation method based on the Galerkin variation,the numerical manifold method(NMM)adopts a double covering system,which can easily deal with discontinuous deformation problems and has a high calculation *** at the thermo-mechanical(TM)coupling problem of fractured rock masses,this study uses the NMM to simulate the processes of crack initiation and propagation in a rock mass under the influence of temperature field,deduces related system equations,and proposes a penalty function method to deal with boundary *** examples are employed to confirm the effectiveness and high accuracy of this *** the thermal stress analysis of a thick-walled cylinder(TWC),the simulation of cracking in the TWC under heating and cooling conditions,and the simulation of thermal cracking of the SwedishÄspöPillar Stability Experiment(APSE)rock column,the thermal stress,and TM coupling are *** numerical simulation results are in good agreement with the test data and other numerical results,thus verifying the effectiveness of the NMM in dealing with thermal stress and crack propagation problems of fractured rock masses.

关键词： Heat conduction Fractured rock mass Crack propagation Galerkin variation Numerical manifold method(NMM)