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Integrating Zeolite and Layered Double Hydroxide for Highly Selective Catalytic Production ofγ-Valerolactone

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CCS Chemistry 2024年第3期6卷 652-662页

作者： Mingkun Gao Guoju Yang Guangyuan He Risheng Bai Jialiang Li Yinghao Liu Qiang Zhang Guangrui Chen Donghai Mei jihong yu State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryInternational Center of Future ScienceJilin UniversityChangchun 130012 School of Materials Science and Engineering Tiangong UniversityTianjin 300387

The production ofγ-valerolactone(GVL)from biomass derivatives levulinic acid(LA)based on acidbase metallic catalysts offers a sustainable pathway to the synthesis of valuable chemicals and ***,the development of efficient metallic catalysts with tunable Lewis acid–base and Brønsted acid sites remains a ***,for the first time,we integrated zeolite and layered double hydroxide(LDH),in a core–shell structure,wherein zeolite and CoFe-LDH provided the Brønsted acidic sites and Lewis acid sites,***,oxygen vacancies(OV_(x))acting as Lewis bases were generated on the surface of LDH via Ga *** efficient cascade catalytic reaction from LA to GVL was successfully achieved over the designed Beta@LDH-OVx catalyst,affording a superior conversion of LA(>99.9%)and an impressive selectivity to GVL(89.18%).Importantly,the“memory effect”of LDH endowed the catalyst with excellent regeneration of metal active *** functional theory calculations revealed that the introduced OVx facilitated the adsorption of carbonyl oxygen in LA and boosted the production of GVL through the synergistic effect of acid/base sites in the composite *** work presents a rational design route for the construction of multifunctional catalysts by coupling zeolites and LDHs for highly selective catalytic conversion of biomass.

关键词： zeolite layered double hydroxide oxygen vacancies biomass γ-valerolactone

Female scientists in nano research

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Nano Research 2023年第3期16卷 3605-3606页

作者： jihong yu State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China International Center of Future Science Jilin UniversityChangchun 130012China

Female scientists are playing more and more important roles in science-related fields,although they just account for a minority(only 30%)of the scientific community worldwide,according to the 2020 data from the Institute for Statistics of *** fact,female researchers have been the mainstay in organizing and guiding the scientific research in many *** the growing impact of female scientists is of significance as role models to enlighten younger generations and particularly encourage young girls to dedicate in *** Special Issue of“Female scientists in nano research”publishes such a collection that shares the research outcomes from those labs led by female scientists in nano-related research fields and showcases their high impacts on many aspects of nanomaterials and *** special issue collects 58 papers,including 16 reviews and 42 original research articles,which present the latest advances in area across diverse compelling topics in nano-science and technology,such as nanoscience for fluorescence and bioimaging,nanomaterials for energy,electronics and catalysis,sensing platforms based on nanoscience,nanobiotechnology and nanomedicine.

关键词： younger UNESCO Female

Preface to special topic on new era of zeolite science

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National Science Review 2022年第9期9卷 6-7页

作者： jihong yu Dongyuan Zhao State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry International Center of Future Science Jilin University NSR Department of Chemistry State Key Laboratory of Molecular Engineering of Polymers Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Laboratory of Advanced Materials and Collaborative Innovation Center of Chemistry for Energy Materials(iChEM) Fudan University

Zeolites are crystalline microporous solids whose frameworks are composed of corner-sharing tetrahedral TO4 units (T=Si,Al, P, etc.), forming periodic one-dimensional (1D) to threedimensional (3D) channels with an aperture size of typically<2 nm. Because of their unique pore structures, large specific surface area, strong acid sites, high thermal/hydrothermal stability and molecular-level shape selectivity, zeolites are widely used as catalysts, adsorbents and ion exchangers in the fields of oil refining, petrochemical industry, coal chemical industry and daily chemical industry.

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Help from space:grant-free massive access for satellite-based IoT in the 6G era

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Digital Communications and Networks 2022年第2期8卷 215-224页

作者： Neng Ye jihong yu Aihua Wang Rongrong Zhang School of Information and Electronics Beijing Institute of TechnologyBeijing100081China Information Engineering College Capital Normal UniversityBeijing100048China

The Sixth-Generation(6G)standard for wireless communications is expected to realize ubiquitous coverage for massive Internet of Things(IoT)networks by ***-based communications are recognized as a highly promising technical enabler to satisfy IoT service requirements in the 6G *** study analyzes multiple access technologies,which are essential for the effective deployment of satellite-based ***,we thoroughly investigate the existing research related to massive access,including information-theory considerations as well as Non-Orthogonal Multiple Access(NOMA)and Random Access(RA)***,we explore the influence of the satellite transmission environment on multiple access *** on this study,a Non-orthogonal Massive Grant-Free Access(NoMaGFA)scheme,which reaps the joint benefits of RA and NOMA,is proposed for asynchronous transmissions in satellite-based IoT to achieve improved system throughput and enhance the system robustness under varying ***,we identify some important and interesting future developments for satellite-based IoT,including waveform design,transceiver design,resource allocation,and artificial intelligence-enhanced design.

关键词： Internet of things Satellite communications Non-orthogonal multiple access Random access Asynchronous transmission

Low-energy adsorptive separation by zeolites

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National Science Review 2022年第9期9卷 120-134页

作者： Ruobing Bai Xiaowei Song Wenfu Yan jihong yu State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University International Center of Future Science Jilin University

Separation of mixture is always necessarily required in modern industry, especially in fine chemical,petrochemical, coal chemical and pharmaceutical industries. The challenge of the separation process is usually associated with small molecules with very similar physical and chemical properties. Among the separation techniques, the commonly used high-pressure cryogenic distillation process with combination of high pressure and very low temperature is heavily energy-consuming, which accounts for the major production costs as well as 10–15% of the world’s energy consumption. To this end, the adsorptive separation process based on zeolite sorbents is a promising lower-energy alternative and the performance is directly determined by the zeolite sorbents. In this review, we surveyed the separation mechanisms based on the steric, equilibrium, kinetic and ‘trapdoor’ effect, and summarized the recent advances in adsorptive separation via zeolites including CO2, light olefins, C8aromatics and hydrogen isotopes. Furthermore, we provided the perspectives on the rational design of zeolite sorbents for the absolute separation of mixtures.

关键词： zeolites adsorptive separation olefin/paraffin separation CO2 separation hydrogen isotope separation

Robust or nonrobust: On MC-DS-CDMA acquisition in LEO satellite communications

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数字通信与网络:英文版 2023年第4期9卷 896-905页

作者： Entong Meng Xiangyuan Bu jihong yu Jianping An Xuanhe Yang School of Information and Electronics Beijing Institute of TechnologyBeijing100081China

Low Earth Orbit(LEO)satellite communications can provide global coverage in the sixth generation communication(6G)*** combat the strong Partial Band Interferences(PBIs)and multipath fading in LEO satellite communication systems,the Multicarrier Direct Sequence Code Division Multiple Access(MC-DS-CDMA)technique is a promising alternative to the traditional Single-carrier Direct Sequence Code Division Multiple Access(SC-DS-CDMA)system for its advantages of high bandwidth efficiency,superior interference rejection capability,and low complexity of parallel signal ***,limited studies have been conducted on the performance analysis of MC-DS-CDMA acquisition systems in the presence of a large Doppler shift,a unique characteristic of LEO satellite *** bridge this gap,we investigate the performance of MC-DS-CDMA systems with two-dimensional acquisition and noncoherent equal gain combining over Rician fading channel in the presence of the Doppler shift and *** performance metrics are detection probability and Mean Square Error(MSE)of the Doppler factor and ***,we derive the closed-form expressions for the MSE and the Probability Density Function(PDF)of the acquisition decision variable and obtain the detection *** conduct extensive numerical experiments to verify the theoretical analysis and performance gain of MC-DSCDMA over the *** results show that MC-DS-CDMA with two-dimensional acquisition is more robust to multipath Rician fading than ***,MC-DS-CDMA outperforms SC-DS-CDMA regarding the detection probability and MSE when combating the strong PBIs.

关键词： Satellite communications MC-DS-CDMA Acquisition performance Rician fading channel Partial band interference

Tailoring Porosity and Titanium Species of TS-1 Zeolites via Organic Base-assisted Sequential Post-treatment

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Chemical Research in Chinese Universities 2022年第1期38卷 50-57页

作者： XU Wenjing LI Li ZHANG Tianjun yu jihong State Key Laboratory of Inorganic Synthesis&Preparative Chemistry Jilin UniversityChangchun 130012P.R.China International Center of Future Science Jilin UniversityChangchun 130012P.R.China

The exploration of high-efficient catalysts based on hierarchical Ti-containing zeolites with optimized active titanium species distribution is of great value in enhancing the epoxidation of bulky olefins. Herein, hierarchical TS-1(MFI) zeolite with an extra-large external surface area(210 m2/g) and highly active octahedral- coordinated Ti species was prepared via organic base-assisted sequential post-treatment. Such a catalyst afforded a high turnover number value(TON, 114) in 1-octene epoxidation reaction, which was over twice than that(53) of the untreated conventional microporous TS-1 parent. According to the detailed characterization results, we revealed the hierarchical porosity construction effect of tetrapropylamonium hydroxide(TPAOH) treatment(first step) and the octahedral-coordinated Ti species fabrication effect of ethylamine(EA) treatment(second step) under hydrothermal condition. Such a facile post-treatment strategy reported in this work may provide guidance for the rational synthesis of TS-1 zeolite with enhanced catalytic activity.

关键词： Post-treatment Hierarchical zeolite TS-1 Ti species Epoxidation

Titanium-rich TS-1 zeolite for highly efficient oxidative desulfurization

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Green Energy & Environment 2023年第1期8卷 163-172页

作者： Risheng Bai yue Song Ge Tian Fei Wang Avelino Corma jihong yu State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun130012China Instituto de Tecnología Química Universitat Politecnica de Valencia-Consejo Superior de Investigaciones CientíficasValencia46022Spain State Key Laboratory of Superhard Materials Jilin UniversityChangchun130012China International Center of Future Science Jilin UniversityChangchun130012China

The exploration of highly efficient catalysts based on nano-sized Ti-rich titanosilicate zeolites with controllable active titanium species is of great importance in zeolite catalytic ***,we reported an efficient and facile synthesis of nano-sized Ti-rich TS-1(MFI)zeolites by replacing tetrabutyl orthotitanate(TBOT)with tetrabutyl orthotitanate tetramer(TBOT-tetramer)as the titanium *** introduced TBOT-tetramer slowed down the zeolite crystallization process,and accordingly balanced the rate of incorporating Ti and the crystal growth and inhibited the massive formation of anatase ***,the prepared Ti-rich TS-1 zeolite sample had a Si/Ti as low as 27.6 in contrast to conventional one with a molar ratio of *** TBOT-tetramer endowed the titanosilicate zeolites with enriched active titanium species and enlarged external surface *** also impeded the formation of anatase species,resulting in superior catalytic behavior toward the oxidative desulfurization of dibenzothiophene compared with the conventional TS-1 zeolite counterpart prepared with TBOT.

关键词： TS-1 Zeolite Ti-rich Heterogeneous catalysis Oxidative desulfurization

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神经网络在无线隐蔽通信中的应用

重庆邮电大学学报（自然科学版） 2024年第2期36卷 250-258页

作者：于季弘林子砚杨传敏蔡雨庭刘家豪王帅北京理工大学信息与电子学院北京100081

无线通信技术已经应用到社会人、机、物等多种元素中,承载着包含多种隐私数据的无线信号。无线传输信道的开放性使其安全性受到了不断的挑战,无线隐蔽通信技术在实现了通信意图安全的同时保证了信息安全和通信路径安全。该文介绍了无线... 详细信息

无线通信技术已经应用到社会人、机、物等多种元素中,承载着包含多种隐私数据的无线信号。无线传输信道的开放性使其安全性受到了不断的挑战,无线隐蔽通信技术在实现了通信意图安全的同时保证了信息安全和通信路径安全。该文介绍了无线隐蔽通信系统的经典模型,并总结、归纳了传统方法下的隐蔽性能分析和隐蔽系统设计;介绍了利用对抗神经网络解决不同隐蔽通信场景下的干扰设计、中继功率分配和可重构智能表面设计等问题;以利用公开信号作为掩体的隐蔽通信场景为例,介绍了一种利用生成对抗网络生成有限长隐蔽信号的方案,并进一步给出应用该网络设计全双工接收机的干扰信号;探讨了神经网络方法在中继隐蔽通信、非正交多址接入(NOMA)下的隐蔽通信,瑞丽衰落下的隐蔽通信,干扰辅助的隐蔽通信场景下的应用前景以及进一步的研究方向。

关键词：无线隐蔽通信神经网络机器学习生成对抗网络