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Metal size effects over metal/zeolite bifunctional catalysts in the selective hydroalkylation of benzene

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 107-114页

作者： Junjie Li Chuang Liu Zhenlong Jia Yingchun Ye Dawei Lan wei meng Jianqiang Wang Zhendong Wang Yongfeng Hu weimin Yang State Key Laboratory of Green Chemical Engineering and Industrial Catalysis Sinopec Shanghai Research Institute of Petrochemical Technology Co.Ltd.Shanghai 201208China School of Chemical Engineering East China University of Science and TechnologyShanghai 200237China

Bifunctional metal/zeolite materials are some of the most suitable catalysts for the direct hydroalkylation of benzene to cyclohexylbenzene.The overall catalytic performance of this reaction is strongly influenced by the hydrogenation,which is dependent on the metal sizes.Thus,systematically investigating the metal size effects in the hydroalkylation of benzene is essential.In this work,we successfully synthesized Ru and Pd nanoparticles on Sinopec Composition Materials No.1 zeolite with various metal sizes.We demonstrated the size-dependent catalytic activity of zeolite-supported Ru and Pd catalysts in the hydroalkylation of benzene,which can be attributed to the size-induced hydrogen spillover capability differences.Our work presents new insights into the hydroalkylation reaction and may open up a new avenue for the smart design of advanced metal/zeolite bi-functional catalysts.

关键词： size effects bifunctional catalysts metal/zeolite hydroalkylation

A novel long persistent luminescent material CaGeO3:Tb3+ with photo-stimulation properties

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Journal of Rare Earths 2024年第7期42卷 1233-1239页

作者： wei meng Xiaoyan Fu Tongyan Lin Zewen Liu Naihui Chen Jiaxu Zhang Runyao Liu Rujun Yang Long Chen Hongwu Zhang School of Chemistry and Material Sciences Ludong University College of Materials Science and Engineering Xiamen University of Technology College of Materials Xiamen University

A novel green long afterglow material CaGeO3:Tb3+was synthesized by high temperature solid phase method.According to the experimental results,CaGeO3:Tb3+is a green long persistent luminescent（LPL）material with excellent performance.CaGeO3:Tb3+shows LPL emission peak at 442,490.9,548.7,588.5and 623.8 nm,corresponding to5D3to7F4and5D4to7FJ（J=6,5,4,3） transitions of Tb3+,Its CIE coordinates are（0.27,0.50）,indicating that the afterglow emission is close to the light of green region.In addition,after the excitation source is turned off,the afterglow time is longer than 90 min.After an interval of 7 h,the photo-stimulation luminescence（PSL） can be observed by using 980 nm laser cyclic excitation.The thermoluminescence（ThL） results show that there are three types of traps in the material and their depths are 0.666,0.774 and 0.892 eV respectively,which are caused by the doping of Tb3+.All the results show that CaGeO3:Tb3+is an excellent long afterglow luminescent material.

关键词： CaGeO3:Tb3+ Long persistent luminescence Photo-stimulation Rare earths Trap

Multiple-dimensioned defect engineering for graphite felt electrode of vanadium redox flow battery

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Carbon Energy 2024年第2期6卷 143-153页

作者： Yingqiao Jiang Yinhui Wang Gang Cheng Yuehua Li Lei Dai Jing Zhu wei meng Jingyu Xi Ling Wang Zhangxing He School of Chemical Engineering North China University of Science and TechnologyTangshanChina Tsinghua Shenzhen International Graduate School Institute of Materials ResearchTsinghua UniversityShenzhenChina

The scarcity of wettability,insufficient active sites,and low surface area of graphite felt(GF)have long been suppressing the performance of vanadium redox flow batteries(VRFBs).Herein,an ultra-homogeneous multipledimensioned defect,including nano-scale etching and atomic-scale N,O codoping,was used to modify GF by the molten salt system.NH_(4)Cl and KClO_(3) were added simultaneously to the system to obtain porous N/O co-doped electrode(GF/ON),where KClO_(3) was used to ultra-homogeneously etch,and O-functionalize electrode,and NH4Cl was used as N dopant,respectively.GF/ON presents better electrochemical catalysis for VO_(2)+/VO_(2)+ and V3+/V2+ reactions than only O-functionalized electrodes(GF/O)and GF.The enhanced electrochemical properties are attributed to an increase in active sites,surface area,and wettability,as well as the synergistic effect of N and O,which is also supported by the density functional theory calculations.Further,the cell using GF/ON shows higher discharge capacity,energy efficiency,and stability for cycling performance than the pristine cell at 140 mA cm^(−2) for 200 cycles.Moreover,the energy efficiency of the modified cell is increased by 9.7% from 55.2% for the pristine cell at 260 mA cm^(−2).Such an ultra-homogeneous etching with N and O co-doping through“boiling”molten salt medium provides an effective and practical application potential way to prepare superior electrodes for VRFB.

关键词： graphite felt molten salt N O co-doping ultra-homogeneous etching vanadium redox flow battery

A Novel Multi-Attribute Decision-Making Method Based on Probabilistic Hesitant Fuzzy Soft Set and Its Application

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Journal of Systems Science and Information 2024年第2期12卷 294-308页

作者： Zhenchun ZANG Jielu LI meng wei College of Computer and Information Engineering Henan University of Economics and LawZhengzhou 450046China

The probabilistic hesitant fuzzy multi-attribute group decision-making method introduces probability and hesitation into decision-making problems at the same time,which can improve the reliability and accuracy of decision-making results,and has become a research hotspots in recent years.However,there are still many problems,such as overly complex calculations and difficulty in obtaining probability data.Based on these,the paper proposes a multi-attribute group decision-making model based on probability hesitant fuzzy soft sets.Firstly,the definition of probabilistic hesitant fuzzy soft set is given.Then,based on soft set theory and probabilistic hesitant fuzzy set,the similarity measure of probabilistic hesitant fuzzy soft set is proposed,and the two measures are further combined.Finally,it is applied to the construction of multi-attribute group decision-making model,and the effectiveness and rationality of the model are verified by an example.The example shows that the new similarity calculation formula and algorithm model in this paper have higher accuracy,and the calculation process is more simple,it provides a feasible method for multi-attribute group decision making problems.

关键词： probabilistic hesitant fuzzy soft sets similarity multi-attribute group decision-making model

New Vacuum Solar Telescope Achieves Narrowband Infrared Solar Imaging Observation at He I 10830 A

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Research in Astronomy and Astrophysics 2024年第5期24卷 76-84页

作者： wei-Jie meng Fang-Yu Xu Zhen-Yu Jin Yunnan ObservatoriesChinese Academy of SciencesKunming 650011China Yunnan Key Laboratory of Solar Physics and Space Sciene Kunming 650216China University of Chinese Academy of Sciences Beijing 100049China

The near-infrared imaging channel constitutes a crucial component of the multichannel high-resolution imaging system of the New Vacuum Solar Telescope(NVST). We have successfully achieved high-resolution, narrowband imaging of the chromosphere using He I 10830 A triplet within this channel, which significantly enhances the imaging observation capabilities of NVST. This paper provides a concise overview of the optical system associated with the near-infrared imaging channel, detailing data processing procedures and presenting several observed images. Leveraging a high-resolution image reconstruction algorithm, we were able to generate a narrowband image near the diffraction limit at 10830 A with a temporal resolution of less than 10 s.

关键词： instrumentation detectors-instrumentation high angular resolution-Sun chromosphere-Sun infrared

Intelligent Reflecting Surface Assisted Transmission Optimization Strategies in Wireless Networks

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China Communications 2024年第4期21卷 120-135页

作者： He Xinxin Qi Xuan meng wei Liu wei Yin Changchuan School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

Wireless Power Transfer(WPT)technology can provide real-time power for many terminal devices in Internet of Things(IoT)through millimeterWave(mmWave)to support applications with large capacity and low latency.Although the intelligent reflecting surface(IRS)can be adopted to create effective virtual links to address the mmWave blockage problem,the conventional solutions only adopt IRS in the downlink from the Base Station(BS)to the users to enhance the received signal strength.In practice,the reflection of IRS is also applicable to the uplink to improve the spectral efficiency.It is a challenging to jointly optimize IRS beamforming and system resource allocation for wireless energy acquisition and information transmission.In this paper,we first design a Low-Energy Adaptive Clustering Hierarchy(LEACH)clustering protocol for clustering and data collection.Then,the problem of maximizing the minimum system spectral efficiency is constructed by jointly optimizing the transmit power of sensor devices,the uplink and downlink transmission times,the active beamforming at the BS,and the IRS dynamic beamforming.To solve this non-convex optimization problem,we propose an alternating optimization(AO)-based joint solution algorithm.Simulation results show that the use of IRS dynamic beamforming can significantly improve the spectral efficiency of the system,and ensure the reliability of equipment communication and the sustainability of energy supply under NLOS link.

关键词： intelligent reflecting surface(IRS) joint optimization millimeter wave wireless information transmission(WIT) wireless power transfer(WPT)

Research on Recommendation Algorithms Based on Cloud Models in Probabilistic Linguistic Environments

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Journal of Systems Science and Information 2024年第1期12卷 96-112页

作者： Peng YANG Xifeng MA meng wei Chunsheng CUI Libin CHE College of Computer and Information Engineering Henan University of Economics and LawZhengzhou 450046China

To solve the problem that the traditional cloud model can't directly process the textual review information in the recommendation algorithm,this paper combines the merits of the cloud model in transforming qualitative and quantitative knowledge with the multi-granularity advantages of probabilistic linguistic term sets in representing uncertain information,and proposes a recommendation algorithm based on cloud model in probabilistic language environment.Initially,this paper quantifies the attributes in the review text based on the probabilistic linguistic term set.Subsequently,the maximum deviation method is used to determine the weight of each attribute in the evaluation information of the product to be recommended,and the comprehensive evaluation number and attribute weight are converted into the digital characteristic value of the cloud model by using the backward cloud generator.Finally,the products are recommended and sorted based on the digital characteristic value of the cloud model.The algorithm is applied to the recommendation of 10 hotels,and the results show that the method is effective and practical,enriching the application of cloud models in the recommendation field.

关键词： recommendation algorithm cloud model probabilistic linguistic term set text reviews

Chiral Dienes: From Ligands to FLP Catalysts

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Chinese Journal of Chemistry 2022年第9期40卷 1109-1116页

作者： Xiangqing Feng wei meng Haifeng Du Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Olefins are very easily accessible compounds which are both popular substrates in synthetic chemistry and good ligands in the organometallic complexes.This dual character makes olefins a rich source of chiral ligands and catalysts for asymmetric catalysis.Herein,we willbriefly summarize our studies on the development of chiral diene ligands for transition-metal catalyzed asymmetric reactions and chiral FLP catalysts for asymmetric metal-free hydrogenations and hydrosilylations.Several acyclic chiral diene ligands as well as P/olefin and S/olefin hybrid ligands were developed for Rh or Pd-catalyzed asymmetric reactions.With these ligands in hand,we further put forward a novel strategy for acquiring chiral FLP catalysts via the in situ hydroboration of chiral dienes with Piers'borane.These catalysts proved to be highly ffective for asymmetric metal-free hydrogenations and hydrosilylations of imines,ilyl enol ethers,ketones,and aromatic N-heterocycles.

关键词： Asymmetric catalysis Chiral dienes Frustrated Lewis pair Conjugated addition Hydrogenation

Phosphatidylcholine deficiency increases ferroptosis susceptibility in the Caenorhabditis elegans germline

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Journal of Genetics and Genomics 2023年第5期50卷 318-329页

作者： Jinglin Zhu wei meng Sin Man Lam Guanghou Shui Xun Huang State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Ferroptosis,a regulated and iron-dependent form of cell death characterized by peroxidation of membrane phospholipids,has tremendous potential for the therapy of human diseases.The causal link between phospholipid homeostasis and ferroptosis is incompletely understood.Here,we reveal that spin-4,a previously identified regulator of the“B12-one-carbon cycle-phosphatidylcholine(PC)”pathway,sustains germline development and fertility by ensuring PC sufficiency in the nematode Caenorhabditis elegans.Mechanistically,SPIN-4 regulates lysosomal activity which is required for B12-associated PC synthesis.PC deficiency-induced sterility can be rescued by reducing the levels of polyunsaturated fatty acids,reactive oxygen species,and redox-active iron,which indicates that the sterility is mediated by germline ferroptosis.These results highlight the critical role of PC homeostasis in ferroptosis susceptibility and offer a new target for pharmacological approaches.

关键词： Phosphatidylcholine Ferroptosis SPIN-4 Sterility Lysosome