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Oxidative Dehydrogenation of 1-Butene to 1,3-Butadiene Using CO2 over Cr-SiO2 Catalysts Prepared by Sol-gel Method

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Chemical Research in Chinese Universities 2018年第4期34卷 609-615页

作者： gao biao LUO Yajun MIAO Changxi YUE Yinghong YANG Weimin HUA Weiming gao Zi Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of Chemistry Fudan University Shanghai 200433 P. R. China Shanghai Research Institute of PetrochemicaI Technology SINOPEC Shanghai 201208 P. R. China

A series of Cr-SiO2 catalysts with a Cr content（mass fraction） ranging from 0.5% to 9% was prepared by a sol-gel method. The catalysts were characterized by XRD, N2 adsorption, EDX elemental mapping, Raman spectros- copy, UV-Vis spectroscopy, XPS and H2-TPR, and their catalytic behavior in the dehydrogenation of 1-butene to 1,3-butadiene（BD） using CO2 as a soft oxidant was studied. The initial BD yield is well correlated with the amount of Cr6~ in the fresh catalysts. The highest BD yield of ca. 34% is achieved on the catalysts with 5%--9% Cr at 600 ~C -1 -1 and weight hourly space velocity（WHSV） of 4.5 g＇geat＇h ~ The promoting effect of CO2 on the BD yield was ob- served, which can be attributed to the reaction coupling between a simple dehydrogenation of 1-butene and the re- verse water-gas shift reaction as well as regaining the oxidation state（lattice oxygen） of reduced Cr3＋ species due to the mild oxidation ability of CO2. The Cr-SiO2 catalyst exhibits higher BD yield than the Cr catalyst supported on SBA-15, which is attributed to the higher amount of Cr6＋ present on the former catalyst.

关键词： 1,3-Butadiene CO2 oxidative dehydrogenation Cr-based catalyst Sol-gel method

Lithiophilic N-doped carbon bowls induced Li deposition in layered graphene film for advanced lithium metal batteries

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Nano Research 2022年第1期15卷 352-360页

作者： Xiaoyu Feng Hong-Hui Wu biao gao Michai Swietostawski Xin He Qiaobao Zhang Department of Materials Science and Engineering College of MaterialsXiamen UniversityXiamen 361005China The State Key Laboratory of Refractories and Metallurgy and Institute of Advanced Materials and Nanotechnology Wuhan University oj Science and TechnologyWuhan 430081y China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Faculty of Chemistry Jagiellonian Universityul.Gronostajowa 230-387 KrakowPoland School of Chemical Engineering Sichuan UniversityChengdu 610065China

Lithium(Li)metal with high theoretical capacity and low electrochemical potential is the most ideal anode for next-generation high-energy ***,the practical implementation of Li anode has been hindered by dendritic growth and volume expansion during cycling,which results in low Coulombic efficiency(CE),short lifespan,and safety ***,we report a highly stable and dendrite-free Li metal anode by utilizing N-doped hollow porous bowl-like hard carbon/reduced graphene nanosheets(CB@rGO)hybrids as three-dimensional(3D)conductive and lithiophilic scaffold *** lithiophilic carbon bowl(CB)mainly works as excellent guides during the Li plating process,whereas the rGO layer with high conductivity and mechanical stability maintains the integrity of the composite by confining the volume change in long-range order during ***,the local current density can be reduced due to the 3D conductive ***,CB@rGO presents a low lithium metal nucleation overpotential of 18 mV,high CE of 98%,and stable cycling without obvious voltage fluctuation for over 600 cycles at a current density of 1 mA cm^(-2).Our study not only provides a good CB@rGO host and pre-Lithiated CB@rGO composite anode electrode,but also brings a new strategy of designing 3D electrodes for those active materials suffering from severe volume expansion.

关键词： dendrite inhibition Li metal host lithium metal battery bowl-like carbon/reduced graphene nanosheets hybrids

Disclosure of charge storage mechanisms in molybdenum oxide nanobelts with enhanced supercapacitive performance induced by oxygen deficiency

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Rare Metals 2021年第9期40卷 2447-2454页

作者： Ping Qin Shi-Qing Zhang Ken-Kin-Lam Yung Zhi-Feng Huang biao gao Department of Physics Golden Meditech Centre for NeuroRegeneration SciencesHong Kong Baptist University(HKBU)Kowloon 999077Hong KongChina Institute of Advanced Materials State Key Laboratory of Environmental and Biological AnalysisHong Kong Baptist University(HKBU)Kowloon 999077Hong KongChina HKBU Institute of Research and Continuing Education Shenzhen 518000China State Key Laboratory of Refractories and Metallurgy and Institute of Advanced Materials and Nanotechnology Wuhan University of Science and TechnologyWuhan 430081China

Molybdenum oxide(MoO_(3)), with superior features of multi-electrochemical states, high theoretical capacitance, and low cost, is a desirable supercapacitor electrode material but suffers from low conductivity and insufficient active sites. The MoO_(3) capacitance can be largely amplified by introducing oxygen(O) vacancies, but the mechanisms at the atomic scale are still ***, O vacancies are created at the O2 and O3 sites in the MoO_(3) nanobelts by carbonization to maximize the supercapacitance in the MoO_(2.39). The supercapacitive storage is mainly ascribed to the proton adsorption at the O1 sites to create Mo–OH, leading to an expansion of the interlayer spacing along the lattice B-axis. Roughly 98% of the initial supercapacitance is retained after 1000 cycles,due to the reversible change in the interlayer spacing. Our results provide an insight into the oxygen deficiency-related mechanisms of the supercapacitive performance at the atomic scale and devise a facile method to enhance the supercapacitance for energy storage and conversion.

关键词： Charge storage mechanisms Oxygen vacancies MoO3 nanobelts Supercapacitance

How to Wear Beautifully？ Clothing Pair Recommendation

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Journal of Computer Science & Technology 2018年第3期33卷 522-530页

作者： Yu-Jie Liu Yong-biao gao Ling-Yan Bian Wen-Ya Wang Zong-Min Li College of Computer and Communication Engineering China University of Petroleum (East China) Qingdao 266580 China

In this paper, we present a practical system to automatically suggest the most pairing clothing items, given the reference clothing （upper-body or low-body）. This has been a challenge, due to clothes having a variety of categories. Clothing is one of the most informative cues for human appearance. In our daily life, people need to wear properly and beautifully to show their confidence, politeness and social status in various occasions. However, it is not easy to decide what to wear and how to coordinate their own clothes. To address this problem, we propose a recommendation approach that includes clothing region detection, clothing pair recommendation and distance fusion. Clothing region detection based on Faster R-CNN is used to detect clothing region. Clothing pair recommendation consists of a quadruple network architecture, where one dual network of the architecture adopts Siamese convolution neural network architecture. Training examples are pairs of upper-body and low-body clothing items that are either compatible or incompatible. The other dual network is used to learn clothing style features of the input image. This framework is designed to learn a feature transformation from the images of clothing items into two latent spaces, which we call them compatible space and style space respectively. After training the two dual networks, we use a distance fusion method to fuse the features extracted from the compatible and style dual networks. To acquire an optimized model and verify our proposed method, we expand an existing large clothing dataset WoG （Weather-to-Garment）, and the resulted dataset is called ＂How to Wear Beautifully＂（H2WB）. Experiments on the H2WB dataset demonstrate that our approach is effective with clothing region detection and clothing pair recommendation as well as distance fusion.

关键词： clothing recommendation clothing pair style learning

Discovery of Kalmane Diterpenoids as Potent Analgesics from the Flowers of Rhododendron dauricum

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Chinese Journal of Chemistry 2022年第9期40卷 1019-1027页

作者： Yuanyuan Feng Suqin Zha biao gao Hanqi Zhang Pengfei Jin Guijuan Zheng Yilin Ma Guangmin Yao Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation School of PharmacyTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430030China

Kalmane diterpenoids,featuring a 5/8/5/5 tetracyclic carbon skeleton,are very rare in *** flowers of Rhododendron dauricum L.(Ericaceae)were phytochemically investigated for the first time,leading to the isolation of eight kalmane diterpenoids(1-8)including four new ones,named rhodokalmanols A-D(1-4).The structures of 1-8 were elucidated by comprehensive spectroscopic methods and ic NMR-DP4+analysis,and the absolute configurations of 1,2,4,and 5 were defined by single-crystal X-ray diffraction analysis with Cu Kα*** A(1)represents the first 5,8-epoxykalmane diterpenoid and also the first kalm-15(16)-ene *** BD(2-4)are the first examples of kalm-7(8)-ene,kalm-16(17)-ene,and 8α-methoxykalmane diterpenoids,*** the isolated kalmane diterpenoids 1-8 exhibited significant analgesic effects,and rhodokalmanol C(3)and kalmanoi(8)expressed more potent analgesic activity than morphine at doses of 0.2 and 0.04 mg/*** preliminary structure-activity relationships of kalmane diterpenoids as potent analgesics are discussed.

关键词： Biological activity Kalmane diterpenoids Natural products Rhododendron dauricum L.(Ericaceae) Structure elucidation

Regional differences of water conservation in Beijing’s forest ecosystem

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Journal of Forestry Research 2011年第2期22卷 295-300页

作者： ZHANG biao XIE gao-di YAN Yu-ping YANG Yan-gang Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Science Beijing 100101 China

The water conservation capacities of main forests in Beijing,China were estimated through the quantitative *** methods developed in published papers on forest hydrology were *** forests in Huairou,Yanqing,Miyun,Mentougou and Fangshan districts are the main contributors to water conservation（the cumulative ratio reaches 65%）,and the forests in Tongzhou,Chaoyang,Shunyi and Daxing districts have the highest water conservation capacity（3000 m3/ha）.Altitude and slope are the key factors to affect the water conservation *** forests located in Plain Area,Hilly Area,Low Mountain,and Middle Mountain contributes 27%,28%,24% and 21% of the conserved water,*** water conservation capacity of forests in Plain Area（2 948 m3/ha）,is superior to the forests in other *** the forests situated on Flat Slope,Moderate Slope and Gentle Slope constitute the largest proportion（nearly 93%） of water conservation,while the forests on Flat Slope has the highest water conservation capacity（2 797 m3/ha）,and the forest on Steep slope has the lowest water conservation capacity（948 m3/ha）.

关键词： forest ecosystem regional difference water conservation Beijing

Rhodauricanol A, an analgesic diterpenoid with an unprecedented5/6/5/7 tetracyclic system featuring a unique16-oxa-tetracyclo[11.2.1.0^(1,5).0^(7,13)]hexadecane core from Rhododendron dauricum

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Chinese Chemical Letters 2023年第4期34卷 183-187页

作者： Yuanyuan Feng Suqin Zha Hanqi Zhang biao gao Guijuan Zheng Pengfei Jin Yingyi Chen Guangmin Yao Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation School of PharmacyTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China

A novel diterpenoid with an unprecedented 5/6/5/7 tetracyclic system, rhodauricanol A(1), five new grayanane-derived diterpenoids, dauricanols A-E(2-6), and five known ones(7-11) were isolated from the flowers of Rhododendron dauricum. Rhodauricanol A(1) possesses a unique 5/6/5/7 tetracyclic ring system featuring a 16-oxa-tetracyclo[11.***.1.0^(1,5).0^(7,13)]hexadecane core. Dauricanols A-C(2-4) are the first1,3-dioxolane conjugates of grayanane diterpenoids and 5-hydroxymethylfurfural and vanillin, respectively, and dauricanols D(5) and E(6) represent the first examples of 6-deoxy-1,5-seco-grayanane diterpenoids. Their structures were determined by spectroscopic methods, quantum chemical calculation including ^(13)C NMR-DP4+ analysis and ECD calculation, and single-crystal X-ray diffraction analysis. Plausible biosynthetic pathways for 1-4 were proposed. All the isolates showed significant analgesic activities,and dauricanols B(3) and C(4) showed more potent analgesic activities than the positive control, morphine.

关键词： Rhododendron dauricum L.(Ericaceae) Diterpenoids Single-crystal X-ray diffraction Biosynthetic pathways Analgesics

Se-Ni Se_(2) hybrid nanosheet arrays with self-regulated elemental Se for efficient alkaline water splitting

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Journal of Materials Science & Technology 2022年第23期118卷 145-152页

作者： Xiang Peng Yujiao Yan Shijian Xiong Yaping Miao Jing Wen Zhitian Liu biao gao Liangsheng Hu Paul K.Chu Hubei Key Laboratory of Plasma Chemistry and Advanced Materials Hubei Engineering Technology Research Center of Optoelectronic and New Energy MaterialsWuhan Institute of TechnologyWuhan 430205China Department of Physics Department of Materials Science and EngineeringDepartment of Biomedical EngineeringCity University of Hong KongTat Chee AvenueKowloonHong KongChina School of Textile Science and Engineering Xi’an Polytechnic UniversityXi’an 710048China State Key Laboratory of Refractories and Metallurgy Institute of Advanced Materials and NanotechnologyWuhan University of Science and TechnologyWuhan 430081China Department of Chemistry Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong ProvinceShantou UniversityShantou 515063China

Understanding the catalytic mechanism of non-noble transition metal electrocatalysts is crucial to designing high-efficiency,low-cost,and durable alternative electrocatalysts for water splitting which comprises the hydrogen evolution reaction(HER) and oxygen evolution reaction(OER).In this work,Se-NiSe_(2) hybrid nanosheets with a self-regulated ratio of ionic Se(I-Se) to elemental Se(E-Se) are designed on carbon cloth by solution synthesis and hydrothermal *** effects of the I-Se/E-Se ratios on the electrocatalytic characteristics in HER and OER are investigated systematically both experimentally and *** optimized bifunctional electrocatalyst needs overpotentials of only 133 mV to deliver an HER current density of 10 mA cm^(-2) and 350 mV to generate an OER current density of 100 mA cm^(-2) in1.0 mol L^(-1) *** on the density-functional theory calculation,surface-adsorbed E-Se is beneficial to optimizing the electron environment and the adsorption/desorption free energy of hydrogen/water of the hybrid catalyst,consequently facilitating the electrocatalytic water splitting *** is a proper I-Se/E-Se ratio to improve the catalytic activity and kinetics of the reaction and the optimized E-Se adsorption amount can balance the interactions between I-Se and E-Se,so that the catalyst can achieve appropriate Se-H binding and active site exposure for the excellent electrocatalytic *** demonstrate the practicality,the assembled symmetrical device can be powered by an AA battery to produce hydrogen and oxygen *** results provide a deeper understanding of the catalytic mechanism of transition metal selenides in water splitting and insights into the design of high-efficiency and low-cost electrocatalysts in energy-related applications.

关键词： Nickel selenide Self-regulation Bifunctional electrocatalysst Water splitting Alkaline hydrogen evolution reaction

Enhanced ion conductivity and electrode–electrolyte interphase stability of porous Si anodes enabled by silicon nitride nanocoating for high-performance Li-ion batteries

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Journal of Energy Chemistry 2022年第6期31卷 616-625,I0017页

作者： Shixiong Mei Siguang Guo Ben Xiang Jiaguo Deng Jijiang Fu Xuming Zhang Yang Zheng biao gao Paul K Chu Kaifu Huo The State Key Laboratory of Refractories and Metallurgy and Institute of Advanced Materials and Nanotechnology Wuhan University of Science and TechnologyWuhan 430081HubeiChina Wuhan National Laboratory for Optoelectronics(WNLO) School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074HubeiChina Department of Physics Department of Materials Science&EngineeringDepartment of Biomedical EngineeringCity University of Hong KongTat Chee AvenueKowloonHong KongChina

Silicon (Si) is a promising anode material for next-generation high-energy lithium-ion batteries (LIBs) due to its high ***,the large volumetric expansion,poor ion conductivity and unstable solid electrolyte interface (SEI) lead to rapid capacity fading and low rate ***,we report Si nitride (SiN) comprising stoichiometric Si_(3)N_(4) and Li-active anazotic SiN_(x) coated porous Si (p-Si@SiN)for high-performance anodes in *** ant-nest-like porous Si consisting of 3D interconnected Si nanoligaments and bicontinuous nanopores prevents pulverization and accommodates volume expansion during *** Si_(3)N_(4) offers mechanically protective coating to endow highly structural integrity and inhibit superfluous formation of *** fast ion conducting Li_(3)N generated in situ from lithiation of active SiN_(x) facilitates Li ion ***,the p-Si@SiN anode has appealing electrochemical properties such as a high capacity of 2180 mAh g^(-1)at 0.5 A g^(-1) with 84%capacity retention after 200cycles and excellent rate capacity with discharge capacity of 721 mAh g^(-1) after 500 cycles at 5.0 A g^(-1).This work provides insights into the rational design of active/inactive nanocoating on Si-based anode materials for fast-charging and highly stable LIBs.

关键词： Silicon anode Ion conductivity Si_(3)N_(4) SiN_(x) Lithium-ion battery