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Study on Catalytic Behavior of Iron-based Catalyst with IITP as Electron Donor in the Polymerization of Butadiene

Chinese Journal of Polymer science 2024年第5期42卷 612-619,I0007页

作者： Shi-Liang Xu Ying-Nan Zhao Yao Yu Qi Yang Li-Hua Na Heng Liu Chun-Yu Zhang Xue-Quan Zhang Key Laboratory of Advanced Rubber Material Ministry of EducationSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Shandong Provincial College Laboratory of Rubber Material and Engineering School of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Key Lab of Rubber-Plastics Ministry of Education/Shandong Provincial Key Lab of Rubber-plasticsSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China

In this study,a novel iron-based catalyst system,Fe(acac)3/(isocyanoimino)triptenylphosphorane(IITP)/AlR3,was employed for the synthesis of syndiotactic 1,2-polybutadiene in *** catalyst system exhibits remarkably high catalytic activity,achieving a polymerization activity of 762 kgpolymer·molcatalyst^(-1)·h^(-1)at 50℃with a[BD]/[Fe]molar ratio of ***,living polymerization characteristic were observed during the investigation of the polymerization kinetics of 1,3-butadiene *** characteristics were well demonstrated by a narrow molecular weight distribution(PDI≈2.0)of the resulting polybutadiene and a linear relationship between-ln(1-c)and polymerization time as well as number average molecular weight and polymer *** resultant polymer showed a 1,2-selectivity of approximately 76%and stereoregularity ranging from 62%to 73%(rrrr).Additionally,through kinetic studies on polymerization reaction,an apparent activation energy Ea value of this catalytic system was calculated to be 84.98 kJ·mol^(-1),which suggests that high polymerization temperature favors efficient polymerization.

关键词： Iron catalyst Syndiotactic 1,2-polybutadiene Elastomers Donor Selectivity

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Adaptive Time Slot Resource Allocation in SWIPT IoT Networks

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Computer Modeling in Engineering & sciences 2023年第9期136卷 2787-2813页

作者： Yunong Yang Yuexia Zhang Zhihai Zhuo Key Laboratory of Information and Communication Systems Ministry of Information IndustryBeijing Information Science and Technology UniversityBeijing100101China Key Laboratory of ModernMeasurement&Control Technology Ministry of EducationBeijing Information Science&Technology UniversityBeijing100101China Beijing Advanced Innovation Center for Future Blockchain and Privacy Computing Beijing100101China

The rapid advancement of Internet of Things(IoT)technology has brought convenience to people’s lives;however further development of IoT faces serious challenges,such as limited energy and shortage of network spectrum *** address the above challenges,this study proposes a simultaneous wireless information and power transfer IoT adaptive time slot resource allocation(SIATS)***,an adaptive time slot consisting of periods for sensing,information transmission,and energy harvesting is designed to ensure that the minimum energy harvesting requirement ismet while the maximumuplink and downlink throughputs are ***,the optimal transmit power and channel assignment of the system are obtained using the Lagrangian dual and gradient descent methods,and the optimal time slot assignment is determined for each IoT device such that the sum of the throughput of all devices is *** results show that the SIATS algorithm performs satisfactorily and provides an increase in the throughput by up to 14.4%compared with that of the fixed time slot allocation(FTS)*** the case of a large noise variance,the SIATS algorithm has good noise immunity,and the total throughput of the IoT devices obtained using the SIATS algorithm can be improved by up to 34.7%compared with that obtained using the FTS algorithm.

关键词： Internet of Things simultaneous wireless information and power transfer adaptive time slot resource allocation

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Changes in tropical cyclone response to the Boreal Summer Intraseasonal Oscillation in the western North Pacific under global warming in EC-Earth3P-HR

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Atmospheric and Oceanic science Letters 2025年第2期18卷 22-28页

作者： Zhefan Gao Chaoxia Yuan Key Laboratory of Meteorological Disaster of Ministry of Education Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersInstitute for Climate and Application Research(ICAR)Nanjing University of Information Science&TechnologyNanjingChina Application Laboratory Japan Agency of Marine-Earth Science and TechnologyYokohamaJapan

EC-Earth3P-HR reproduces well the observed Boreal Summer Intraseasonal Oscillation(BSISO)and its impacts on tropical cyclone genesis(TCG)in the western North Pacific(WNP).Hence,the historical simulation(1950-1979)and future projection under the SSP5-8.5 scenario(2020-2049)in EC-Earth3P-HR are adopted to explore possible changes in the BSISO’s modification of WNP TCG under global warming to enhance the understanding of TC activities in the *** show that the BSISO circulation in the WNP shifts northeastward under global *** leads to enhanced convection in a northwest-southeast-oriented band crossing the *** the band,the BSISO-related TCG anomalies are *** of genesis potential index show that changes in the BSISO-related mid-tropospheric relative humidity play the dominant role in modifying the BSISO’s impacts on WNP TCG under global *** enhanced BSISO convection in the band moistens the middle troposphere,which helps reduce the entrainment of generally dry mid-tropospheric air in the updrafts and the modification of the boundary layer by the downdraft of generally dry mid-tropospheric air,leading to enhanced TCG.

关键词： Global warming Tropical cyclones BSISO

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Natural keratin-based Fe-S_(1)N_(3) single atom catalyst for insights into the coordination regulation effect of Fenton-like catalysis with high efficiency

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Nano Research 2023年第7期16卷 9003-9011页

作者： Zhiyi Sun Yujuan Wei Ting Cao Zheng Liu Rui Sui Xiang Li Jiajing Pei Zhuo Chen Shuo Wang Energy&Catalysis Center School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China College of Textile and Garments Hebei University of Science&TechnologyThe Innovation Center of Textile and Garment TechnologyHebei 050018China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China SEPA Key Laboratory of Eco-Industry Chinese Research Academy of Environmental SciencesBeijing 100012China Department of Chemistry Tsinghua UniversityBeijing 100084China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Single atom catalysts(SACs)have attracted great attention,yet the quest for highly-efficient catalysts is driven by the current obstacles of ambiguous structure-performance ***,we report a nature keratin-based Fe-S_(1)N_(3)SACs with ultrathin two-dimensional(2D)porous carbon nanosheets structure,by controlling the active center through the precise coordination of sulfur and *** with natural silk-based Fe-N_(4) catalyst,the Fe-S_(1)N_(3)SACs exhibit excellent Fenton-like oxidation degradation ability.X-ray absorption fine structure(XAFS)and electron paramagnetic resonance(EPR)results confirm that S doping is conducive to electron transfer,to accurately generate·OH with high oxidative degradation capacity at the active ***,the optimized Fe-S_(1)N_(3)catalyst showed higher oxidation degradation activity for organic pollutant substrates(methylene blue(MB),Rhodamine B(RhB)and phenol),significantly superior to Fe-N_(4) *** work is devoted to the treatment and application of natural fibers,which provides a novel method for the synthesis of SACs and the regulation of atomic coordination environment.

关键词： iron single atom atomic regulation natural fiber Fenton-like catalysis

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Novel polysaccharide from Panax notoginseng with immunoregulation and prebiotic effects

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Food Bioscience 2023年第1期51卷 1038-1045页

作者： Hui-Rong Yang Xue Li Hao Liu Dong-Rui Zhao Ying-Jie Zeng College of Food Science&Technology Southwest Minzu UniversityChengdu610041China Key Laboratory of Brewing Molecular Engineering of China Light Industry Beijing100048China

Panax notoginseng is a rare medicinal and edible plant widely used for multi-treatments,and in this study,a polysaccharide Pnp was prepared from ***,and its structure and biology activities were *** showed that the molecular weight of Pnp was 78.6 kDa,and Pnp mainly consisted of→2,4)-α-L-Rhap-(1→,→5)-α-L-Araf-(1→and→4)-α-D-Galp-(1→residues with acetyl ***,the macrophages were activated the immunologic function after TLR2 and MR recognizing ***,Pnp could be durative utilized by the probiotic Lactobacillus plantarum and the account of viable cells kept at 9.5 log CFU/mL for *** hydrophobicity and the short-chain fatty acids levels(especially butyric acid)of *** were enhanced by Pnp,which indicated that Pnp exerted beneficial effects on the host *** results laid a solid foundation for the exploitation of Pnp as a nutraceutical and functional candidate in the food industry.

关键词： Panax notoginseng Polysaccharides Structure Bioactivity

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MZI/FPI Fiber Optic Dual-parameter Sensor Based on a Double Cone and Air Cavity Structure(Invited)

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光子学报 2024年第10期53卷 64-72页

作者： YUAN Tingxuan ZHAO Lilong REN Jianxin MAO Yaya ULLAH Rahat WU Xiangyu MAO Beibei XIA Wenchao Institute of Optics and Electronics Nanjing University of Information Science&TechnologyNanjing 210044China Jiangsu Key Laboratory for Optoelectronic Detection of Atmosphere and Ocean Nanjing University of Information Science&TechnologyNanjing 210044China Jiangsu International Joint Laboratory on Meteorological Photonics and Optoelectronic Detection Nanjing University of Information Science&TechnologyNanjing 210044China

This paper proposes a Mach Zehnder/Fabry Perot Interferometer(MZI/FPI)fiber sensor based on Single-mode Fiber(SMF)and Hollow-core Fiber(HCF),which has high sensitivity to temperature and lateral *** proposed device consists of two single-mode fiber cones formed by manually controlling the fusion splicer and an air cavity formed by fusing a section of hollow-core *** structure of the sensor is a double cone cascaded air *** the beginning of the design,we compared the basic transmission spectra of single cone structure and double cone structure experimentally,and therefore chose to use double cone structure and air cavity *** undergoes its first reflection at the first interface between the single-mode fiber and the air cavity structure,and its second reflection at the second interface between the air cavity structure and the single-mode *** two reflected light waves produced by the two reflections form FP interference,which can be used to measure lateral *** transmitted light is excited through the first cone,and a portion of the core mode light is excited to the cladding,while another portion of the core mode light continues to propagate in the *** light couples at the second cone,and the cladding mode light couples back into the core,forming MZ interference with the core mode light,which can be used to measure *** use of hollow-core fiber to form an air cavity has little effect on transmitted light,while avoiding the problem of crosstalk in dual parameter *** designing temperature and lateral load experiments,this article verifies the sensitivity characteristics of this sensor to temperature and lateral loads.A significant redshift phenomenon was observed in the temperature experiment.A significant redshift phenomenon also occurred in the lateral load *** wavelength demodulation,the experimental results show that the wavelength sensitivity of the sensor to temperature is 56.29 pm/℃i

关键词： Temperature Lateral load Fiber sensor Mach-Zehnder interferometer Fabry-Pérot interferometer

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Inhibiting plastic tensile instability of non-symmetric thin-walled shell component via increasing regional metal inflow based on heterogeneous pressure-carrying medium

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Chinese Journal of Aeronautics 2024年第1期37卷 391-413页

作者： Nan XIANG Yiquan SHU Pengyi WANG Menghan YANG Haoran WANG Tao HUANG Junqing GUO Fuxiao CHEN School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471023China National Key Laboratory for Precision Heat Processing of Metals School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China College of Mechanical&Electrical Engineering Shaanxi University of Science&TechnologyXi’an 710021China Provincial and Ministerial Co-construction of Collaborative Innovation Center for Non-ferrous Metal new Materials and Advanced Processing Technology Luoyang 471023China

Heterogeneous pressure-carrying medium was employed to establish a differentiated pressure field on sheet metal in flexible die forming process in this work,which aimed at matching the non-symmetric shape of target component and improving metal inflow to avoid local tensile ***,metal inflow corresponding to the differentiated pressure field was analytically *** of a typical non-symmetric shell component was experimentally and numerically studied based on the proposed *** with forming processes based on the uniform pressure,difference of metal inflow in two sides of the non-symmetric component increased from 2.16 mm to 3.36 mm and metal inflow in critical region increased by 11.9%when differentiated pressure field(taking heterogeneous elastomer#4–3 for example)was *** resultant maximum thinning ratio decreased by 4.2% and the uniformity of shell thickness increased by 16.9%.With the decrease of Shore hardness of elastomer in the formed region,stress path in the ready-to-form region transferred towards the bi-axial tension stress state,i.e.,stress ratio(a)***,stress triaxiality(η)in characteristic regions were regulated appropriately,which decreased the risk of tensile *** was attributed to the decreased normal pressure and frictional resistance at sheet/elastomer interface in the formed region.

关键词： Aluminum alloys Finite element method Metal forming Plastic deformation Sheet metal

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A novel natural surface-enhanced fluorescence system based on reed leaf as substrate for crystal violet trace detection

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Chinese Physics B 2022年第10期31卷 539-548页

作者： Hui-Ju Cao Hong-Wen Cao Yue Li Zhen Sun Yun-Fan Yang Ti-Feng Jiao Ming-Li Wan State Key Laboratory of Materials Science&Technology and Key Laboratory for Microstructural Material Physics of Hebei Province School of ScienceYanshan UniversityQinhuangdao 066004China Hebei Key Laboratory of Applied Chemistry School of Environmental and Chemical EngineeringYanshan UniversityQinhuangdao 066004China

The preparation of surface-enhanced fluorescence(SEF) substrates is often influenced by experimental strategies and factors such as the morphology and size of the nanostructures. In this study, using the natural reed leaves(RLs) without any special pretreatment as the substrate, metal silver is modified by magnetron sputtering technology to prepare a stable and efficient SEF system. The abundant “hedgehog-like” protrusions on the RL substrate surface can generate high-density“hot spots”, thus enhancement factor(EF) is enhanced up to 3345 times. The stability and reproducibility are verified in many measurements. The contribution of the intervention of silver nanostructure to the radiation attenuation process of fluorescent molecules is analyzed with the aid of Jablonski diagrams. Three-dimensional(3D) finite difference time domain(FDTD) simulates the spatial electric field and “hot spots” distribution of the substrate. The “hedgehog-like” protrusion structure generates multiple “hot spots”, which produce an excellent local surface plasmon resonance(LSPR) effect and provide higher fluorescence signal. Finally, RL/Ag-35 substrate is used to detect crystal violet(CV), and the detection limit is as low as 10^(-13) M. This “hedgehog-like” SEF substrate provides a new strategy for the trace detection of CV, which has a good practical application value.

关键词： surface-enhanced fluorescence biological materials reed leaf hot spots

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Fullerene-Intercalated Graphitic Carbon Nitride as a HighPerformance Anode Material for Sodium-Ion Batteries

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Energy & Environmental Materials 2022年第2期5卷 608-616页

作者： Pengju Li Yanglin Shen Ximing Li Wenhuan Huang Xing Lu Shaanxi Key Laboratory of Chemical Additives for Industry College of Chemistry&Chemical EngineeringShaanxi University of Science&TechnologyXi’an 710021China State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Two-dimensional(2D)graphitic carbon nitride(g-CN)is a promising anode material for sodium-ion batteries(SIBs),but its insufficient interlayer spacing and poor electronic conductivity impede its sodium storage capacity and cycling ***,we report the fabrication of a fullerene(C_(60))-modified graphitic carbon nitride(C_(60)@CN)material which as an anode material for SIBs shows a high-reversible capacity(430.5 mA h g^(−1) at 0.05 A g^(−1),about 3 times higher than that of pristine g-CN),excellent rate capability(226.6 mA h g^(−1) at 1 A g^(−1))and ultra-long cycle life(101.2 mA h g^(−1) after 5000 cycles at 5 A g^(−1)).Even at a high-active mass loading of 3.7 mg cm^(−2),a reversible capacity of 316.3 mA h g^(−1) can be obtained after 100 *** outstanding performance of C_(60)@CN is attributed to the C_(60) molecules distributed in the g-CN nanosheets,which enhance the electronic conductivity and prevent g-CN sheets from restacking,thus resulting in enlarged interlayer spacing and exposed edge N defects(pyridinic N and pyrrolic N)for sodium-ion ***,a sodium-ion full cell combining C60@CN anode and NVPF@rGO cathode provides high-coulombic efficiency(>96.5%),exceptionally high-energy density(359.8 W h kganode−1 at power density of 105.1 W kganode−1)and excellent cycling stability(89.2%capacity retention over 500 cycles at 1Aganode−1).This work brings new insights into the field of carbon-based anode materials for SIBs.

关键词： energy storage fullerene interlayer distance nitrogen-doped carbon materials

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Decomposition mechanisms of nuclear-grade cationic exchange resin by advanced oxidation processes:Statistical molecular fragmentation model and DFT calculations

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Journal of Environmental sciences 2024年第1期135卷 433-448页

作者： Xiang Meng Pierre Désesquelles Lejin Xu Department of Nuclear Engineering and Technology School of Energy and Power EngineeringHuazhong University of Science&TechnologyWuhan 430074China CNRS Laboratoire de Physique des Gaz et des PlasmasUniversitéParis-SaclayOrsay 91405France State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The treatment and disposal of radioactive waste are presently facing great *** ion exchange resins have become a focus of attention due to their high production and serious environmental *** this paper,a simplified model of cationic exchange resin is proposed,and the degradation processes of cationic resin monomer initiated by hydroxyl radicals(·OH)are clarified by combining statistical molecular fragmentation(SMF)model and density functional theory(DFT)*** prediction of active sites indicates that the S-O bonds and the C-S bond of the sulfonic group are more likely to react during the *** meta-position of the sulfonic group on the benzene ring is the most active site,and the benzene ring without the sulfonic group has a certain *** C11-C14 and C17-C20 bonds,on the carbon skeleton,are the most easily *** is also found that dihydroxy addition and elimination reactions play a major role in the process of desulfonation,carbon skeleton cleavage and benzene ring *** decomposition mechanisms found through the combination of physical models and chemical calculations,provide theoretical guidance for the treatment of complex polycyclic aromatic hydrocarbons.

关键词： Cationic exchange resin Statistical molecular fragmentation model Density functional theory Hydroxyl radical Decomposition mechanism

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